1 /*-
2 * Copyright (c) 2016-2020 Netflix, Inc.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 *
25 */
26 /**
27 * Author: Randall Stewart <rrs@netflix.com>
28 * This work is based on the ACM Queue paper
29 * BBR - Congestion Based Congestion Control
30 * and also numerous discussions with Neal, Yuchung and Van.
31 */
32
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35
36 #include "opt_inet.h"
37 #include "opt_inet6.h"
38 #include "opt_ipsec.h"
39 #include "opt_ratelimit.h"
40 #include <sys/param.h>
41 #include <sys/arb.h>
42 #include <sys/module.h>
43 #include <sys/kernel.h>
44 #include <sys/libkern.h>
45 #ifdef TCP_HHOOK
46 #include <sys/hhook.h>
47 #endif
48 #include <sys/malloc.h>
49 #include <sys/mbuf.h>
50 #include <sys/proc.h>
51 #include <sys/socket.h>
52 #include <sys/socketvar.h>
53 #include <sys/sysctl.h>
54 #include <sys/systm.h>
55 #ifdef STATS
56 #include <sys/qmath.h>
57 #include <sys/tree.h>
58 #include <sys/stats.h> /* Must come after qmath.h and tree.h */
59 #endif
60 #include <sys/refcount.h>
61 #include <sys/queue.h>
62 #include <sys/eventhandler.h>
63 #include <sys/smp.h>
64 #include <sys/kthread.h>
65 #include <sys/lock.h>
66 #include <sys/mutex.h>
67 #include <sys/tim_filter.h>
68 #include <sys/time.h>
69 #include <sys/protosw.h>
70 #include <vm/uma.h>
71 #include <sys/kern_prefetch.h>
72
73 #include <net/route.h>
74 #include <net/route/nhop.h>
75 #include <net/vnet.h>
76
77 #define TCPSTATES /* for logging */
78
79 #include <netinet/in.h>
80 #include <netinet/in_kdtrace.h>
81 #include <netinet/in_pcb.h>
82 #include <netinet/ip.h>
83 #include <netinet/ip_icmp.h> /* required for icmp_var.h */
84 #include <netinet/icmp_var.h> /* for ICMP_BANDLIM */
85 #include <netinet/ip_var.h>
86 #include <netinet/ip6.h>
87 #include <netinet6/in6_pcb.h>
88 #include <netinet6/ip6_var.h>
89 #define TCPOUTFLAGS
90 #include <netinet/tcp.h>
91 #include <netinet/tcp_fsm.h>
92 #include <netinet/tcp_seq.h>
93 #include <netinet/tcp_timer.h>
94 #include <netinet/tcp_var.h>
95 #include <netinet/tcpip.h>
96 #include <netinet/tcp_hpts.h>
97 #include <netinet/cc/cc.h>
98 #include <netinet/tcp_log_buf.h>
99 #include <netinet/tcp_ratelimit.h>
100 #include <netinet/tcp_lro.h>
101 #ifdef TCP_OFFLOAD
102 #include <netinet/tcp_offload.h>
103 #endif
104 #ifdef INET6
105 #include <netinet6/tcp6_var.h>
106 #endif
107 #include <netinet/tcp_fastopen.h>
108
109 #include <netipsec/ipsec_support.h>
110 #include <net/if.h>
111 #include <net/if_var.h>
112 #include <net/ethernet.h>
113
114 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
115 #include <netipsec/ipsec.h>
116 #include <netipsec/ipsec6.h>
117 #endif /* IPSEC */
118
119 #include <netinet/udp.h>
120 #include <netinet/udp_var.h>
121 #include <machine/in_cksum.h>
122
123 #ifdef MAC
124 #include <security/mac/mac_framework.h>
125 #endif
126
127 #include "sack_filter.h"
128 #include "tcp_bbr.h"
129 #include "rack_bbr_common.h"
130 uma_zone_t bbr_zone;
131 uma_zone_t bbr_pcb_zone;
132
133 struct sysctl_ctx_list bbr_sysctl_ctx;
134 struct sysctl_oid *bbr_sysctl_root;
135
136 #define TCPT_RANGESET_NOSLOP(tv, value, tvmin, tvmax) do { \
137 (tv) = (value); \
138 if ((u_long)(tv) < (u_long)(tvmin)) \
139 (tv) = (tvmin); \
140 if ((u_long)(tv) > (u_long)(tvmax)) \
141 (tv) = (tvmax); \
142 } while(0)
143
144 /*#define BBR_INVARIANT 1*/
145
146 /*
147 * initial window
148 */
149 static uint32_t bbr_def_init_win = 10;
150 static int32_t bbr_persist_min = 250000; /* 250ms */
151 static int32_t bbr_persist_max = 1000000; /* 1 Second */
152 static int32_t bbr_cwnd_may_shrink = 0;
153 static int32_t bbr_cwndtarget_rtt_touse = BBR_RTT_PROP;
154 static int32_t bbr_num_pktepo_for_del_limit = BBR_NUM_RTTS_FOR_DEL_LIMIT;
155 static int32_t bbr_hardware_pacing_limit = 8000;
156 static int32_t bbr_quanta = 3; /* How much extra quanta do we get? */
157 static int32_t bbr_no_retran = 0;
158
159 static int32_t bbr_error_base_paceout = 10000; /* usec to pace */
160 static int32_t bbr_max_net_error_cnt = 10;
161 /* Should the following be dynamic too -- loss wise */
162 static int32_t bbr_rtt_gain_thresh = 0;
163 /* Measurement controls */
164 static int32_t bbr_use_google_algo = 1;
165 static int32_t bbr_ts_limiting = 1;
166 static int32_t bbr_ts_can_raise = 0;
167 static int32_t bbr_do_red = 600;
168 static int32_t bbr_red_scale = 20000;
169 static int32_t bbr_red_mul = 1;
170 static int32_t bbr_red_div = 2;
171 static int32_t bbr_red_growth_restrict = 1;
172 static int32_t bbr_target_is_bbunit = 0;
173 static int32_t bbr_drop_limit = 0;
174 /*
175 * How much gain do we need to see to
176 * stay in startup?
177 */
178 static int32_t bbr_marks_rxt_sack_passed = 0;
179 static int32_t bbr_start_exit = 25;
180 static int32_t bbr_low_start_exit = 25; /* When we are in reduced gain */
181 static int32_t bbr_startup_loss_thresh = 2000; /* 20.00% loss */
182 static int32_t bbr_hptsi_max_mul = 1; /* These two mul/div assure a min pacing */
183 static int32_t bbr_hptsi_max_div = 2; /* time, 0 means turned off. We need this
184 * if we go back ever to where the pacer
185 * has priority over timers.
186 */
187 static int32_t bbr_policer_call_from_rack_to = 0;
188 static int32_t bbr_policer_detection_enabled = 1;
189 static int32_t bbr_min_measurements_req = 1; /* We need at least 2
190 * measurements before we are
191 * "good" note that 2 == 1.
192 * This is because we use a >
193 * comparison. This means if
194 * min_measure was 0, it takes
195 * num-measures > min(0) and
196 * you get 1 measurement and
197 * you are good. Set to 1, you
198 * have to have two
199 * measurements (this is done
200 * to prevent it from being ok
201 * to have no measurements). */
202 static int32_t bbr_no_pacing_until = 4;
203
204 static int32_t bbr_min_usec_delta = 20000; /* 20,000 usecs */
205 static int32_t bbr_min_peer_delta = 20; /* 20 units */
206 static int32_t bbr_delta_percent = 150; /* 15.0 % */
207
208 static int32_t bbr_target_cwnd_mult_limit = 8;
209 /*
210 * bbr_cwnd_min_val is the number of
211 * segments we hold to in the RTT probe
212 * state typically 4.
213 */
214 static int32_t bbr_cwnd_min_val = BBR_PROBERTT_NUM_MSS;
215
216 static int32_t bbr_cwnd_min_val_hs = BBR_HIGHSPEED_NUM_MSS;
217
218 static int32_t bbr_gain_to_target = 1;
219 static int32_t bbr_gain_gets_extra_too = 1;
220 /*
221 * bbr_high_gain is the 2/ln(2) value we need
222 * to double the sending rate in startup. This
223 * is used for both cwnd and hptsi gain's.
224 */
225 static int32_t bbr_high_gain = BBR_UNIT * 2885 / 1000 + 1;
226 static int32_t bbr_startup_lower = BBR_UNIT * 1500 / 1000 + 1;
227 static int32_t bbr_use_lower_gain_in_startup = 1;
228
229 /* thresholds for reduction on drain in sub-states/drain */
230 static int32_t bbr_drain_rtt = BBR_SRTT;
231 static int32_t bbr_drain_floor = 88;
232 static int32_t google_allow_early_out = 1;
233 static int32_t google_consider_lost = 1;
234 static int32_t bbr_drain_drop_mul = 4;
235 static int32_t bbr_drain_drop_div = 5;
236 static int32_t bbr_rand_ot = 50;
237 static int32_t bbr_can_force_probertt = 0;
238 static int32_t bbr_can_adjust_probertt = 1;
239 static int32_t bbr_probertt_sets_rtt = 0;
240 static int32_t bbr_can_use_ts_for_rtt = 1;
241 static int32_t bbr_is_ratio = 0;
242 static int32_t bbr_sub_drain_app_limit = 1;
243 static int32_t bbr_prtt_slam_cwnd = 1;
244 static int32_t bbr_sub_drain_slam_cwnd = 1;
245 static int32_t bbr_slam_cwnd_in_main_drain = 1;
246 static int32_t bbr_filter_len_sec = 6; /* How long does the rttProp filter
247 * hold */
248 static uint32_t bbr_rtt_probe_limit = (USECS_IN_SECOND * 4);
249 /*
250 * bbr_drain_gain is the reverse of the high_gain
251 * designed to drain back out the standing queue
252 * that is formed in startup by causing a larger
253 * hptsi gain and thus drainging the packets
254 * in flight.
255 */
256 static int32_t bbr_drain_gain = BBR_UNIT * 1000 / 2885;
257 static int32_t bbr_rttprobe_gain = 192;
258
259 /*
260 * The cwnd_gain is the default cwnd gain applied when
261 * calculating a target cwnd. Note that the cwnd is
262 * a secondary factor in the way BBR works (see the
263 * paper and think about it, it will take some time).
264 * Basically the hptsi_gain spreads the packets out
265 * so you never get more than BDP to the peer even
266 * if the cwnd is high. In our implemenation that
267 * means in non-recovery/retransmission scenarios
268 * cwnd will never be reached by the flight-size.
269 */
270 static int32_t bbr_cwnd_gain = BBR_UNIT * 2;
271 static int32_t bbr_tlp_type_to_use = BBR_SRTT;
272 static int32_t bbr_delack_time = 100000; /* 100ms in useconds */
273 static int32_t bbr_sack_not_required = 0; /* set to one to allow non-sack to use bbr */
274 static int32_t bbr_initial_bw_bps = 62500; /* 500kbps in bytes ps */
275 static int32_t bbr_ignore_data_after_close = 1;
276 static int16_t bbr_hptsi_gain[] = {
277 (BBR_UNIT *5 / 4),
278 (BBR_UNIT * 3 / 4),
279 BBR_UNIT,
280 BBR_UNIT,
281 BBR_UNIT,
282 BBR_UNIT,
283 BBR_UNIT,
284 BBR_UNIT
285 };
286 int32_t bbr_use_rack_resend_cheat = 1;
287 int32_t bbr_sends_full_iwnd = 1;
288
289 #define BBR_HPTSI_GAIN_MAX 8
290 /*
291 * The BBR module incorporates a number of
292 * TCP ideas that have been put out into the IETF
293 * over the last few years:
294 * - Yuchung Cheng's RACK TCP (for which its named) that
295 * will stop us using the number of dup acks and instead
296 * use time as the gage of when we retransmit.
297 * - Reorder Detection of RFC4737 and the Tail-Loss probe draft
298 * of Dukkipati et.al.
299 * - Van Jacobson's et.al BBR.
300 *
301 * RACK depends on SACK, so if an endpoint arrives that
302 * cannot do SACK the state machine below will shuttle the
303 * connection back to using the "default" TCP stack that is
304 * in FreeBSD.
305 *
306 * To implement BBR and RACK the original TCP stack was first decomposed
307 * into a functional state machine with individual states
308 * for each of the possible TCP connection states. The do_segment
309 * functions role in life is to mandate the connection supports SACK
310 * initially and then assure that the RACK state matches the conenction
311 * state before calling the states do_segment function. Data processing
312 * of inbound segments also now happens in the hpts_do_segment in general
313 * with only one exception. This is so we can keep the connection on
314 * a single CPU.
315 *
316 * Each state is simplified due to the fact that the original do_segment
317 * has been decomposed and we *know* what state we are in (no
318 * switches on the state) and all tests for SACK are gone. This
319 * greatly simplifies what each state does.
320 *
321 * TCP output is also over-written with a new version since it
322 * must maintain the new rack scoreboard and has had hptsi
323 * integrated as a requirment. Still todo is to eliminate the
324 * use of the callout_() system and use the hpts for all
325 * timers as well.
326 */
327 static uint32_t bbr_rtt_probe_time = 200000; /* 200ms in micro seconds */
328 static uint32_t bbr_rtt_probe_cwndtarg = 4; /* How many mss's outstanding */
329 static const int32_t bbr_min_req_free = 2; /* The min we must have on the
330 * free list */
331 static int32_t bbr_tlp_thresh = 1;
332 static int32_t bbr_reorder_thresh = 2;
333 static int32_t bbr_reorder_fade = 60000000; /* 0 - never fade, def
334 * 60,000,000 - 60 seconds */
335 static int32_t bbr_pkt_delay = 1000;
336 static int32_t bbr_min_to = 1000; /* Number of usec's minimum timeout */
337 static int32_t bbr_incr_timers = 1;
338
339 static int32_t bbr_tlp_min = 10000; /* 10ms in usecs */
340 static int32_t bbr_delayed_ack_time = 200000; /* 200ms in usecs */
341 static int32_t bbr_exit_startup_at_loss = 1;
342
343 /*
344 * bbr_lt_bw_ratio is 1/8th
345 * bbr_lt_bw_diff is < 4 Kbit/sec
346 */
347 static uint64_t bbr_lt_bw_diff = 4000 / 8; /* In bytes per second */
348 static uint64_t bbr_lt_bw_ratio = 8; /* For 1/8th */
349 static uint32_t bbr_lt_bw_max_rtts = 48; /* How many rtt's do we use
350 * the lt_bw for */
351 static uint32_t bbr_lt_intvl_min_rtts = 4; /* Min num of RTT's to measure
352 * lt_bw */
353 static int32_t bbr_lt_intvl_fp = 0; /* False positive epoch diff */
354 static int32_t bbr_lt_loss_thresh = 196; /* Lost vs delivered % */
355 static int32_t bbr_lt_fd_thresh = 100; /* false detection % */
356
357 static int32_t bbr_verbose_logging = 0;
358 /*
359 * Currently regular tcp has a rto_min of 30ms
360 * the backoff goes 12 times so that ends up
361 * being a total of 122.850 seconds before a
362 * connection is killed.
363 */
364 static int32_t bbr_rto_min_ms = 30; /* 30ms same as main freebsd */
365 static int32_t bbr_rto_max_sec = 4; /* 4 seconds */
366
367 /****************************************************/
368 /* DEFAULT TSO SIZING (cpu performance impacting) */
369 /****************************************************/
370 /* What amount is our formula using to get TSO size */
371 static int32_t bbr_hptsi_per_second = 1000;
372
373 /*
374 * For hptsi under bbr_cross_over connections what is delay
375 * target 7ms (in usec) combined with a seg_max of 2
376 * gets us close to identical google behavior in
377 * TSO size selection (possibly more 1MSS sends).
378 */
379 static int32_t bbr_hptsi_segments_delay_tar = 7000;
380
381 /* Does pacing delay include overhead's in its time calculations? */
382 static int32_t bbr_include_enet_oh = 0;
383 static int32_t bbr_include_ip_oh = 1;
384 static int32_t bbr_include_tcp_oh = 1;
385 static int32_t bbr_google_discount = 10;
386
387 /* Do we use (nf mode) pkt-epoch to drive us or rttProp? */
388 static int32_t bbr_state_is_pkt_epoch = 0;
389 static int32_t bbr_state_drain_2_tar = 1;
390 /* What is the max the 0 - bbr_cross_over MBPS TSO target
391 * can reach using our delay target. Note that this
392 * value becomes the floor for the cross over
393 * algorithm.
394 */
395 static int32_t bbr_hptsi_segments_max = 2;
396 static int32_t bbr_hptsi_segments_floor = 1;
397 static int32_t bbr_hptsi_utter_max = 0;
398
399 /* What is the min the 0 - bbr_cross-over MBPS TSO target can be */
400 static int32_t bbr_hptsi_bytes_min = 1460;
401 static int32_t bbr_all_get_min = 0;
402
403 /* Cross over point from algo-a to algo-b */
404 static uint32_t bbr_cross_over = TWENTY_THREE_MBPS;
405
406 /* Do we deal with our restart state? */
407 static int32_t bbr_uses_idle_restart = 0;
408 static int32_t bbr_idle_restart_threshold = 100000; /* 100ms in useconds */
409
410 /* Do we allow hardware pacing? */
411 static int32_t bbr_allow_hdwr_pacing = 0;
412 static int32_t bbr_hdwr_pace_adjust = 2; /* multipler when we calc the tso size */
413 static int32_t bbr_hdwr_pace_floor = 1;
414 static int32_t bbr_hdwr_pacing_delay_cnt = 10;
415
416 /****************************************************/
417 static int32_t bbr_resends_use_tso = 0;
418 static int32_t bbr_tlp_max_resend = 2;
419 static int32_t bbr_sack_block_limit = 128;
420
421 #define BBR_MAX_STAT 19
422 counter_u64_t bbr_state_time[BBR_MAX_STAT];
423 counter_u64_t bbr_state_lost[BBR_MAX_STAT];
424 counter_u64_t bbr_state_resend[BBR_MAX_STAT];
425 counter_u64_t bbr_stat_arry[BBR_STAT_SIZE];
426 counter_u64_t bbr_opts_arry[BBR_OPTS_SIZE];
427 counter_u64_t bbr_out_size[TCP_MSS_ACCT_SIZE];
428 counter_u64_t bbr_flows_whdwr_pacing;
429 counter_u64_t bbr_flows_nohdwr_pacing;
430
431 counter_u64_t bbr_nohdwr_pacing_enobuf;
432 counter_u64_t bbr_hdwr_pacing_enobuf;
433
434 static inline uint64_t bbr_get_bw(struct tcp_bbr *bbr);
435
436 /*
437 * Static defintions we need for forward declarations.
438 */
439 static uint32_t
440 bbr_get_pacing_length(struct tcp_bbr *bbr, uint16_t gain,
441 uint32_t useconds_time, uint64_t bw);
442 static uint32_t
443 bbr_get_a_state_target(struct tcp_bbr *bbr, uint32_t gain);
444 static void
445 bbr_set_state(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t win);
446 static void
447 bbr_set_probebw_gains(struct tcp_bbr *bbr, uint32_t cts, uint32_t losses);
448 static void
449 bbr_substate_change(struct tcp_bbr *bbr, uint32_t cts, int line,
450 int dolog);
451 static uint32_t
452 bbr_get_target_cwnd(struct tcp_bbr *bbr, uint64_t bw, uint32_t gain);
453 static void
454 bbr_state_change(struct tcp_bbr *bbr, uint32_t cts, int32_t epoch,
455 int32_t pkt_epoch, uint32_t losses);
456 static uint32_t
457 bbr_calc_thresh_rack(struct tcp_bbr *bbr, uint32_t srtt, uint32_t cts,
458 struct bbr_sendmap *rsm);
459 static uint32_t
460 bbr_initial_cwnd(struct tcp_bbr *bbr, struct tcpcb *tp);
461 static uint32_t
462 bbr_calc_thresh_tlp(struct tcpcb *tp, struct tcp_bbr *bbr,
463 struct bbr_sendmap *rsm, uint32_t srtt, uint32_t cts);
464 static void
465 bbr_exit_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts,
466 int32_t line);
467 static void
468 bbr_set_state_target(struct tcp_bbr *bbr, int line);
469 static void
470 bbr_enter_probe_rtt(struct tcp_bbr *bbr, uint32_t cts, int32_t line);
471 static void
472 bbr_log_progress_event(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t tick,
473 int event, int line);
474 static void
475 tcp_bbr_tso_size_check(struct tcp_bbr *bbr, uint32_t cts);
476 static void
477 bbr_setup_red_bw(struct tcp_bbr *bbr, uint32_t cts);
478 static void
479 bbr_log_rtt_shrinks(struct tcp_bbr *bbr, uint32_t cts, uint32_t applied,
480 uint32_t rtt, uint32_t line, uint8_t is_start,
481 uint16_t set);
482 static struct bbr_sendmap *
483 bbr_find_lowest_rsm(struct tcp_bbr *bbr);
484 static __inline uint32_t
485 bbr_get_rtt(struct tcp_bbr *bbr, int32_t rtt_type);
486 static void
487 bbr_log_to_start(struct tcp_bbr *bbr, uint32_t cts, uint32_t to, int32_t slot,
488 uint8_t which);
489 static void
490 bbr_log_timer_var(struct tcp_bbr *bbr, int mode, uint32_t cts,
491 uint32_t time_since_sent, uint32_t srtt,
492 uint32_t thresh, uint32_t to);
493 static void
494 bbr_log_hpts_diag(struct tcp_bbr *bbr, uint32_t cts, struct hpts_diag *diag);
495 static void
496 bbr_log_type_bbrsnd(struct tcp_bbr *bbr, uint32_t len, uint32_t slot,
497 uint32_t del_by, uint32_t cts, uint32_t sloton,
498 uint32_t prev_delay);
499 static void
500 bbr_enter_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts,
501 int32_t line);
502 static void
503 bbr_stop_all_timers(struct tcpcb *tp);
504 static void
505 bbr_exit_probe_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts);
506 static void
507 bbr_check_probe_rtt_limits(struct tcp_bbr *bbr, uint32_t cts);
508 static void
509 bbr_timer_cancel(struct tcp_bbr *bbr, int32_t line, uint32_t cts);
510 static void
511 bbr_log_pacing_delay_calc(struct tcp_bbr *bbr, uint16_t gain, uint32_t len,
512 uint32_t cts, uint32_t usecs, uint64_t bw,
513 uint32_t override, int mod);
514 static int
515 bbr_ctloutput(struct inpcb *inp, struct sockopt *sopt);
516
517 static inline uint8_t
518 bbr_state_val(struct tcp_bbr *bbr)
519 {
520 return(bbr->rc_bbr_substate);
521 }
522
523 static inline uint32_t
524 get_min_cwnd(struct tcp_bbr *bbr)
525 {
526 int mss;
527
528 mss = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options),
529 bbr->r_ctl.rc_pace_max_segs);
530 if (bbr_get_rtt(bbr, BBR_RTT_PROP) < BBR_HIGH_SPEED)
531 return (bbr_cwnd_min_val_hs * mss);
532 else
533 return (bbr_cwnd_min_val * mss);
534 }
535
536 static uint32_t
537 bbr_get_persists_timer_val(struct tcpcb *tp, struct tcp_bbr *bbr)
538 {
539 uint64_t srtt, var;
540 uint64_t ret_val;
541
542 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_PERSIT;
543 if (tp->t_srtt == 0) {
544 srtt = (uint64_t)BBR_INITIAL_RTO;
545 var = 0;
546 } else {
547 srtt = ((uint64_t)TICKS_2_USEC(tp->t_srtt) >> TCP_RTT_SHIFT);
548 var = ((uint64_t)TICKS_2_USEC(tp->t_rttvar) >> TCP_RTT_SHIFT);
549 }
550 TCPT_RANGESET_NOSLOP(ret_val, ((srtt + var) * tcp_backoff[tp->t_rxtshift]),
551 bbr_persist_min, bbr_persist_max);
552 return ((uint32_t)ret_val);
553 }
554
555 static uint32_t
556 bbr_timer_start(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts)
557 {
558 /*
559 * Start the FR timer, we do this based on getting the first one in
560 * the rc_tmap. Note that if its NULL we must stop the timer. in all
561 * events we need to stop the running timer (if its running) before
562 * starting the new one.
563 */
564 uint32_t thresh, exp, to, srtt, time_since_sent, tstmp_touse;
565 int32_t idx;
566 int32_t is_tlp_timer = 0;
567 struct bbr_sendmap *rsm;
568
569 if (bbr->rc_all_timers_stopped) {
570 /* All timers have been stopped none are to run */
571 return (0);
572 }
573 if (bbr->rc_in_persist) {
574 /* We can't start any timer in persists */
575 return (bbr_get_persists_timer_val(tp, bbr));
576 }
577 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap);
578 if ((rsm == NULL) ||
579 ((tp->t_flags & TF_SACK_PERMIT) == 0) ||
580 (tp->t_state < TCPS_ESTABLISHED)) {
581 /* Nothing on the send map */
582 activate_rxt:
583 if (SEQ_LT(tp->snd_una, tp->snd_max) ||
584 sbavail(&tptosocket(tp)->so_snd)) {
585 uint64_t tov;
586
587 time_since_sent = 0;
588 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap);
589 if (rsm) {
590 idx = rsm->r_rtr_cnt - 1;
591 if (TSTMP_GEQ(rsm->r_tim_lastsent[idx], bbr->r_ctl.rc_tlp_rxt_last_time))
592 tstmp_touse = rsm->r_tim_lastsent[idx];
593 else
594 tstmp_touse = bbr->r_ctl.rc_tlp_rxt_last_time;
595 if (TSTMP_GT(tstmp_touse, cts))
596 time_since_sent = cts - tstmp_touse;
597 }
598 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_RXT;
599 if (tp->t_srtt == 0)
600 tov = BBR_INITIAL_RTO;
601 else
602 tov = ((uint64_t)(TICKS_2_USEC(tp->t_srtt) +
603 ((uint64_t)TICKS_2_USEC(tp->t_rttvar) * (uint64_t)4)) >> TCP_RTT_SHIFT);
604 if (tp->t_rxtshift)
605 tov *= tcp_backoff[tp->t_rxtshift];
606 if (tov > time_since_sent)
607 tov -= time_since_sent;
608 else
609 tov = bbr->r_ctl.rc_min_to;
610 TCPT_RANGESET_NOSLOP(to, tov,
611 (bbr->r_ctl.rc_min_rto_ms * MS_IN_USEC),
612 (bbr->rc_max_rto_sec * USECS_IN_SECOND));
613 bbr_log_timer_var(bbr, 2, cts, 0, srtt, 0, to);
614 return (to);
615 }
616 return (0);
617 }
618 if (rsm->r_flags & BBR_ACKED) {
619 rsm = bbr_find_lowest_rsm(bbr);
620 if (rsm == NULL) {
621 /* No lowest? */
622 goto activate_rxt;
623 }
624 }
625 /* Convert from ms to usecs */
626 if (rsm->r_flags & BBR_SACK_PASSED) {
627 if ((tp->t_flags & TF_SENTFIN) &&
628 ((tp->snd_max - tp->snd_una) == 1) &&
629 (rsm->r_flags & BBR_HAS_FIN)) {
630 /*
631 * We don't start a bbr rack timer if all we have is
632 * a FIN outstanding.
633 */
634 goto activate_rxt;
635 }
636 srtt = bbr_get_rtt(bbr, BBR_RTT_RACK);
637 thresh = bbr_calc_thresh_rack(bbr, srtt, cts, rsm);
638 idx = rsm->r_rtr_cnt - 1;
639 exp = rsm->r_tim_lastsent[idx] + thresh;
640 if (SEQ_GEQ(exp, cts)) {
641 to = exp - cts;
642 if (to < bbr->r_ctl.rc_min_to) {
643 to = bbr->r_ctl.rc_min_to;
644 }
645 } else {
646 to = bbr->r_ctl.rc_min_to;
647 }
648 } else {
649 /* Ok we need to do a TLP not RACK */
650 if (bbr->rc_tlp_in_progress != 0) {
651 /*
652 * The previous send was a TLP.
653 */
654 goto activate_rxt;
655 }
656 rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_tmap, bbr_sendmap, r_tnext);
657 if (rsm == NULL) {
658 /* We found no rsm to TLP with. */
659 goto activate_rxt;
660 }
661 if (rsm->r_flags & BBR_HAS_FIN) {
662 /* If its a FIN we don't do TLP */
663 rsm = NULL;
664 goto activate_rxt;
665 }
666 time_since_sent = 0;
667 idx = rsm->r_rtr_cnt - 1;
668 if (TSTMP_GEQ(rsm->r_tim_lastsent[idx], bbr->r_ctl.rc_tlp_rxt_last_time))
669 tstmp_touse = rsm->r_tim_lastsent[idx];
670 else
671 tstmp_touse = bbr->r_ctl.rc_tlp_rxt_last_time;
672 if (TSTMP_GT(tstmp_touse, cts))
673 time_since_sent = cts - tstmp_touse;
674 is_tlp_timer = 1;
675 srtt = bbr_get_rtt(bbr, bbr_tlp_type_to_use);
676 thresh = bbr_calc_thresh_tlp(tp, bbr, rsm, srtt, cts);
677 if (thresh > time_since_sent)
678 to = thresh - time_since_sent;
679 else
680 to = bbr->r_ctl.rc_min_to;
681 if (to > (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND)) {
682 /*
683 * If the TLP time works out to larger than the max
684 * RTO lets not do TLP.. just RTO.
685 */
686 goto activate_rxt;
687 }
688 if ((bbr->rc_tlp_rtx_out == 1) &&
689 (rsm->r_start == bbr->r_ctl.rc_last_tlp_seq)) {
690 /*
691 * Second retransmit of the same TLP
692 * lets not.
693 */
694 bbr->rc_tlp_rtx_out = 0;
695 goto activate_rxt;
696 }
697 if (rsm->r_start != bbr->r_ctl.rc_last_tlp_seq) {
698 /*
699 * The tail is no longer the last one I did a probe
700 * on
701 */
702 bbr->r_ctl.rc_tlp_seg_send_cnt = 0;
703 bbr->r_ctl.rc_last_tlp_seq = rsm->r_start;
704 }
705 }
706 if (is_tlp_timer == 0) {
707 BBR_STAT_INC(bbr_to_arm_rack);
708 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_RACK;
709 } else {
710 bbr_log_timer_var(bbr, 1, cts, time_since_sent, srtt, thresh, to);
711 if (bbr->r_ctl.rc_tlp_seg_send_cnt > bbr_tlp_max_resend) {
712 /*
713 * We have exceeded how many times we can retran the
714 * current TLP timer, switch to the RTO timer.
715 */
716 goto activate_rxt;
717 } else {
718 BBR_STAT_INC(bbr_to_arm_tlp);
719 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_TLP;
720 }
721 }
722 return (to);
723 }
724
725 static inline int32_t
726 bbr_minseg(struct tcp_bbr *bbr)
727 {
728 return (bbr->r_ctl.rc_pace_min_segs - bbr->rc_last_options);
729 }
730
731 static void
732 bbr_start_hpts_timer(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t cts, int32_t frm, int32_t slot, uint32_t tot_len)
733 {
734 struct inpcb *inp = tptoinpcb(tp);
735 struct hpts_diag diag;
736 uint32_t delayed_ack = 0;
737 uint32_t left = 0;
738 uint32_t hpts_timeout;
739 uint8_t stopped;
740 int32_t delay_calc = 0;
741 uint32_t prev_delay = 0;
742
743 if (tcp_in_hpts(inp)) {
744 /* A previous call is already set up */
745 return;
746 }
747 if ((tp->t_state == TCPS_CLOSED) ||
748 (tp->t_state == TCPS_LISTEN)) {
749 return;
750 }
751 stopped = bbr->rc_tmr_stopped;
752 if (stopped && TSTMP_GT(bbr->r_ctl.rc_timer_exp, cts)) {
753 left = bbr->r_ctl.rc_timer_exp - cts;
754 }
755 bbr->r_ctl.rc_hpts_flags = 0;
756 bbr->r_ctl.rc_timer_exp = 0;
757 prev_delay = bbr->r_ctl.rc_last_delay_val;
758 if (bbr->r_ctl.rc_last_delay_val &&
759 (slot == 0)) {
760 /*
761 * If a previous pacer delay was in place we
762 * are not coming from the output side (where
763 * we calculate a delay, more likely a timer).
764 */
765 slot = bbr->r_ctl.rc_last_delay_val;
766 if (TSTMP_GT(cts, bbr->rc_pacer_started)) {
767 /* Compensate for time passed */
768 delay_calc = cts - bbr->rc_pacer_started;
769 if (delay_calc <= slot)
770 slot -= delay_calc;
771 }
772 }
773 /* Do we have early to make up for by pushing out the pacing time? */
774 if (bbr->r_agg_early_set) {
775 bbr_log_pacing_delay_calc(bbr, 0, bbr->r_ctl.rc_agg_early, cts, slot, 0, bbr->r_agg_early_set, 2);
776 slot += bbr->r_ctl.rc_agg_early;
777 bbr->r_ctl.rc_agg_early = 0;
778 bbr->r_agg_early_set = 0;
779 }
780 /* Are we running a total debt that needs to be compensated for? */
781 if (bbr->r_ctl.rc_hptsi_agg_delay) {
782 if (slot > bbr->r_ctl.rc_hptsi_agg_delay) {
783 /* We nuke the delay */
784 slot -= bbr->r_ctl.rc_hptsi_agg_delay;
785 bbr->r_ctl.rc_hptsi_agg_delay = 0;
786 } else {
787 /* We nuke some of the delay, put in a minimal 100usecs */
788 bbr->r_ctl.rc_hptsi_agg_delay -= slot;
789 bbr->r_ctl.rc_last_delay_val = slot = 100;
790 }
791 }
792 bbr->r_ctl.rc_last_delay_val = slot;
793 hpts_timeout = bbr_timer_start(tp, bbr, cts);
794 if (tp->t_flags & TF_DELACK) {
795 if (bbr->rc_in_persist == 0) {
796 delayed_ack = bbr_delack_time;
797 } else {
798 /*
799 * We are in persists and have
800 * gotten a new data element.
801 */
802 if (hpts_timeout > bbr_delack_time) {
803 /*
804 * Lets make the persists timer (which acks)
805 * be the smaller of hpts_timeout and bbr_delack_time.
806 */
807 hpts_timeout = bbr_delack_time;
808 }
809 }
810 }
811 if (delayed_ack &&
812 ((hpts_timeout == 0) ||
813 (delayed_ack < hpts_timeout))) {
814 /* We need a Delayed ack timer */
815 bbr->r_ctl.rc_hpts_flags = PACE_TMR_DELACK;
816 hpts_timeout = delayed_ack;
817 }
818 if (slot) {
819 /* Mark that we have a pacing timer up */
820 BBR_STAT_INC(bbr_paced_segments);
821 bbr->r_ctl.rc_hpts_flags |= PACE_PKT_OUTPUT;
822 }
823 /*
824 * If no timers are going to run and we will fall off thfe hptsi
825 * wheel, we resort to a keep-alive timer if its configured.
826 */
827 if ((hpts_timeout == 0) &&
828 (slot == 0)) {
829 if ((V_tcp_always_keepalive || inp->inp_socket->so_options & SO_KEEPALIVE) &&
830 (tp->t_state <= TCPS_CLOSING)) {
831 /*
832 * Ok we have no timer (persists, rack, tlp, rxt or
833 * del-ack), we don't have segments being paced. So
834 * all that is left is the keepalive timer.
835 */
836 if (TCPS_HAVEESTABLISHED(tp->t_state)) {
837 hpts_timeout = TICKS_2_USEC(TP_KEEPIDLE(tp));
838 } else {
839 hpts_timeout = TICKS_2_USEC(TP_KEEPINIT(tp));
840 }
841 bbr->r_ctl.rc_hpts_flags |= PACE_TMR_KEEP;
842 }
843 }
844 if (left && (stopped & (PACE_TMR_KEEP | PACE_TMR_DELACK)) ==
845 (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK)) {
846 /*
847 * RACK, TLP, persists and RXT timers all are restartable
848 * based on actions input .. i.e we received a packet (ack
849 * or sack) and that changes things (rw, or snd_una etc).
850 * Thus we can restart them with a new value. For
851 * keep-alive, delayed_ack we keep track of what was left
852 * and restart the timer with a smaller value.
853 */
854 if (left < hpts_timeout)
855 hpts_timeout = left;
856 }
857 if (bbr->r_ctl.rc_incr_tmrs && slot &&
858 (bbr->r_ctl.rc_hpts_flags & (PACE_TMR_TLP|PACE_TMR_RXT))) {
859 /*
860 * If configured to do so, and the timer is either
861 * the TLP or RXT timer, we need to increase the timeout
862 * by the pacing time. Consider the bottleneck at my
863 * machine as an example, we are sending something
864 * to start a TLP on. The last packet won't be emitted
865 * fully until the pacing time (the bottleneck will hold
866 * the data in place). Once the packet is emitted that
867 * is when we want to start waiting for the TLP. This
868 * is most evident with hardware pacing (where the nic
869 * is holding the packet(s) before emitting). But it
870 * can also show up in the network so we do it for all
871 * cases. Technically we would take off one packet from
872 * this extra delay but this is easier and being more
873 * conservative is probably better.
874 */
875 hpts_timeout += slot;
876 }
877 if (hpts_timeout) {
878 /*
879 * Hack alert for now we can't time-out over 2147 seconds (a
880 * bit more than 35min)
881 */
882 if (hpts_timeout > 0x7ffffffe)
883 hpts_timeout = 0x7ffffffe;
884 bbr->r_ctl.rc_timer_exp = cts + hpts_timeout;
885 } else
886 bbr->r_ctl.rc_timer_exp = 0;
887 if ((slot) &&
888 (bbr->rc_use_google ||
889 bbr->output_error_seen ||
890 (slot <= hpts_timeout)) ) {
891 /*
892 * Tell LRO that it can queue packets while
893 * we pace.
894 */
895 bbr->rc_inp->inp_flags2 |= INP_MBUF_QUEUE_READY;
896 if ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK) &&
897 (bbr->rc_cwnd_limited == 0)) {
898 /*
899 * If we are not cwnd limited and we
900 * are running a rack timer we put on
901 * the do not disturbe even for sack.
902 */
903 inp->inp_flags2 |= INP_DONT_SACK_QUEUE;
904 } else
905 inp->inp_flags2 &= ~INP_DONT_SACK_QUEUE;
906 bbr->rc_pacer_started = cts;
907
908 (void)tcp_hpts_insert_diag(inp, HPTS_USEC_TO_SLOTS(slot),
909 __LINE__, &diag);
910 bbr->rc_timer_first = 0;
911 bbr->bbr_timer_src = frm;
912 bbr_log_to_start(bbr, cts, hpts_timeout, slot, 1);
913 bbr_log_hpts_diag(bbr, cts, &diag);
914 } else if (hpts_timeout) {
915 (void)tcp_hpts_insert_diag(inp, HPTS_USEC_TO_SLOTS(hpts_timeout),
916 __LINE__, &diag);
917 /*
918 * We add the flag here as well if the slot is set,
919 * since hpts will call in to clear the queue first before
920 * calling the output routine (which does our timers).
921 * We don't want to set the flag if its just a timer
922 * else the arrival of data might (that causes us
923 * to send more) might get delayed. Imagine being
924 * on a keep-alive timer and a request comes in for
925 * more data.
926 */
927 if (slot)
928 bbr->rc_pacer_started = cts;
929 if ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK) &&
930 (bbr->rc_cwnd_limited == 0)) {
931 /*
932 * For a rack timer, don't wake us even
933 * if a sack arrives as long as we are
934 * not cwnd limited.
935 */
936 bbr->rc_inp->inp_flags2 |= INP_MBUF_QUEUE_READY;
937 inp->inp_flags2 |= INP_DONT_SACK_QUEUE;
938 } else {
939 /* All other timers wake us up */
940 bbr->rc_inp->inp_flags2 &= ~INP_MBUF_QUEUE_READY;
941 inp->inp_flags2 &= ~INP_DONT_SACK_QUEUE;
942 }
943 bbr->bbr_timer_src = frm;
944 bbr_log_to_start(bbr, cts, hpts_timeout, slot, 0);
945 bbr_log_hpts_diag(bbr, cts, &diag);
946 bbr->rc_timer_first = 1;
947 }
948 bbr->rc_tmr_stopped = 0;
949 bbr_log_type_bbrsnd(bbr, tot_len, slot, delay_calc, cts, frm, prev_delay);
950 }
951
952 static void
953 bbr_timer_audit(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, struct sockbuf *sb)
954 {
955 /*
956 * We received an ack, and then did not call send or were bounced
957 * out due to the hpts was running. Now a timer is up as well, is it
958 * the right timer?
959 */
960 struct inpcb *inp;
961 struct bbr_sendmap *rsm;
962 uint32_t hpts_timeout;
963 int tmr_up;
964
965 tmr_up = bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK;
966 if (bbr->rc_in_persist && (tmr_up == PACE_TMR_PERSIT))
967 return;
968 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap);
969 if (((rsm == NULL) || (tp->t_state < TCPS_ESTABLISHED)) &&
970 (tmr_up == PACE_TMR_RXT)) {
971 /* Should be an RXT */
972 return;
973 }
974 inp = bbr->rc_inp;
975 if (rsm == NULL) {
976 /* Nothing outstanding? */
977 if (tp->t_flags & TF_DELACK) {
978 if (tmr_up == PACE_TMR_DELACK)
979 /*
980 * We are supposed to have delayed ack up
981 * and we do
982 */
983 return;
984 } else if (sbavail(&inp->inp_socket->so_snd) &&
985 (tmr_up == PACE_TMR_RXT)) {
986 /*
987 * if we hit enobufs then we would expect the
988 * possibility of nothing outstanding and the RXT up
989 * (and the hptsi timer).
990 */
991 return;
992 } else if (((V_tcp_always_keepalive ||
993 inp->inp_socket->so_options & SO_KEEPALIVE) &&
994 (tp->t_state <= TCPS_CLOSING)) &&
995 (tmr_up == PACE_TMR_KEEP) &&
996 (tp->snd_max == tp->snd_una)) {
997 /* We should have keep alive up and we do */
998 return;
999 }
1000 }
1001 if (rsm && (rsm->r_flags & BBR_SACK_PASSED)) {
1002 if ((tp->t_flags & TF_SENTFIN) &&
1003 ((tp->snd_max - tp->snd_una) == 1) &&
1004 (rsm->r_flags & BBR_HAS_FIN)) {
1005 /* needs to be a RXT */
1006 if (tmr_up == PACE_TMR_RXT)
1007 return;
1008 else
1009 goto wrong_timer;
1010 } else if (tmr_up == PACE_TMR_RACK)
1011 return;
1012 else
1013 goto wrong_timer;
1014 } else if (rsm && (tmr_up == PACE_TMR_RACK)) {
1015 /* Rack timer has priority if we have data out */
1016 return;
1017 } else if (SEQ_GT(tp->snd_max, tp->snd_una) &&
1018 ((tmr_up == PACE_TMR_TLP) ||
1019 (tmr_up == PACE_TMR_RXT))) {
1020 /*
1021 * Either a TLP or RXT is fine if no sack-passed is in place
1022 * and data is outstanding.
1023 */
1024 return;
1025 } else if (tmr_up == PACE_TMR_DELACK) {
1026 /*
1027 * If the delayed ack was going to go off before the
1028 * rtx/tlp/rack timer were going to expire, then that would
1029 * be the timer in control. Note we don't check the time
1030 * here trusting the code is correct.
1031 */
1032 return;
1033 }
1034 if (SEQ_GT(tp->snd_max, tp->snd_una) &&
1035 ((tmr_up == PACE_TMR_RXT) ||
1036 (tmr_up == PACE_TMR_TLP) ||
1037 (tmr_up == PACE_TMR_RACK))) {
1038 /*
1039 * We have outstanding data and
1040 * we *do* have a RACK, TLP or RXT
1041 * timer running. We won't restart
1042 * anything here since thats probably ok we
1043 * will get called with some timer here shortly.
1044 */
1045 return;
1046 }
1047 /*
1048 * Ok the timer originally started is not what we want now. We will
1049 * force the hpts to be stopped if any, and restart with the slot
1050 * set to what was in the saved slot.
1051 */
1052 wrong_timer:
1053 if ((bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == 0) {
1054 if (tcp_in_hpts(inp))
1055 tcp_hpts_remove(inp);
1056 bbr_timer_cancel(bbr, __LINE__, cts);
1057 bbr_start_hpts_timer(bbr, tp, cts, 1, bbr->r_ctl.rc_last_delay_val,
1058 0);
1059 } else {
1060 /*
1061 * Output is hptsi so we just need to switch the type of
1062 * timer. We don't bother with keep-alive, since when we
1063 * jump through the output, it will start the keep-alive if
1064 * nothing is sent.
1065 *
1066 * We only need a delayed-ack added and or the hpts_timeout.
1067 */
1068 hpts_timeout = bbr_timer_start(tp, bbr, cts);
1069 if (tp->t_flags & TF_DELACK) {
1070 if (hpts_timeout == 0) {
1071 hpts_timeout = bbr_delack_time;
1072 bbr->r_ctl.rc_hpts_flags = PACE_TMR_DELACK;
1073 }
1074 else if (hpts_timeout > bbr_delack_time) {
1075 hpts_timeout = bbr_delack_time;
1076 bbr->r_ctl.rc_hpts_flags = PACE_TMR_DELACK;
1077 }
1078 }
1079 if (hpts_timeout) {
1080 if (hpts_timeout > 0x7ffffffe)
1081 hpts_timeout = 0x7ffffffe;
1082 bbr->r_ctl.rc_timer_exp = cts + hpts_timeout;
1083 }
1084 }
1085 }
1086
1087 int32_t bbr_clear_lost = 0;
1088
1089 /*
1090 * Considers the two time values now (cts) and earlier.
1091 * If cts is smaller than earlier, we could have
1092 * had a sequence wrap (our counter wraps every
1093 * 70 min or so) or it could be just clock skew
1094 * getting us two different time values. Clock skew
1095 * will show up within 10ms or so. So in such
1096 * a case (where cts is behind earlier time by
1097 * less than 10ms) we return 0. Otherwise we
1098 * return the true difference between them.
1099 */
1100 static inline uint32_t
1101 bbr_calc_time(uint32_t cts, uint32_t earlier_time) {
1102 /*
1103 * Given two timestamps, the current time stamp cts, and some other
1104 * time-stamp taken in theory earlier return the difference. The
1105 * trick is here sometimes locking will get the other timestamp
1106 * after the cts. If this occurs we need to return 0.
1107 */
1108 if (TSTMP_GEQ(cts, earlier_time))
1109 return (cts - earlier_time);
1110 /*
1111 * cts is behind earlier_time if its less than 10ms consider it 0.
1112 * If its more than 10ms difference then we had a time wrap. Else
1113 * its just the normal locking foo. I wonder if we should not go to
1114 * 64bit TS and get rid of this issue.
1115 */
1116 if (TSTMP_GEQ((cts + 10000), earlier_time))
1117 return (0);
1118 /*
1119 * Ok the time must have wrapped. So we need to answer a large
1120 * amount of time, which the normal subtraction should do.
1121 */
1122 return (cts - earlier_time);
1123 }
1124
1125 static int
1126 sysctl_bbr_clear_lost(SYSCTL_HANDLER_ARGS)
1127 {
1128 uint32_t stat;
1129 int32_t error;
1130
1131 error = SYSCTL_OUT(req, &bbr_clear_lost, sizeof(uint32_t));
1132 if (error || req->newptr == NULL)
1133 return error;
1134
1135 error = SYSCTL_IN(req, &stat, sizeof(uint32_t));
1136 if (error)
1137 return (error);
1138 if (stat == 1) {
1139 #ifdef BBR_INVARIANTS
1140 printf("Clearing BBR lost counters\n");
1141 #endif
1142 COUNTER_ARRAY_ZERO(bbr_state_lost, BBR_MAX_STAT);
1143 COUNTER_ARRAY_ZERO(bbr_state_time, BBR_MAX_STAT);
1144 COUNTER_ARRAY_ZERO(bbr_state_resend, BBR_MAX_STAT);
1145 } else if (stat == 2) {
1146 #ifdef BBR_INVARIANTS
1147 printf("Clearing BBR option counters\n");
1148 #endif
1149 COUNTER_ARRAY_ZERO(bbr_opts_arry, BBR_OPTS_SIZE);
1150 } else if (stat == 3) {
1151 #ifdef BBR_INVARIANTS
1152 printf("Clearing BBR stats counters\n");
1153 #endif
1154 COUNTER_ARRAY_ZERO(bbr_stat_arry, BBR_STAT_SIZE);
1155 } else if (stat == 4) {
1156 #ifdef BBR_INVARIANTS
1157 printf("Clearing BBR out-size counters\n");
1158 #endif
1159 COUNTER_ARRAY_ZERO(bbr_out_size, TCP_MSS_ACCT_SIZE);
1160 }
1161 bbr_clear_lost = 0;
1162 return (0);
1163 }
1164
1165 static void
1166 bbr_init_sysctls(void)
1167 {
1168 struct sysctl_oid *bbr_probertt;
1169 struct sysctl_oid *bbr_hptsi;
1170 struct sysctl_oid *bbr_measure;
1171 struct sysctl_oid *bbr_cwnd;
1172 struct sysctl_oid *bbr_timeout;
1173 struct sysctl_oid *bbr_states;
1174 struct sysctl_oid *bbr_startup;
1175 struct sysctl_oid *bbr_policer;
1176
1177 /* Probe rtt controls */
1178 bbr_probertt = SYSCTL_ADD_NODE(&bbr_sysctl_ctx,
1179 SYSCTL_CHILDREN(bbr_sysctl_root),
1180 OID_AUTO,
1181 "probertt",
1182 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1183 "");
1184 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1185 SYSCTL_CHILDREN(bbr_probertt),
1186 OID_AUTO, "gain", CTLFLAG_RW,
1187 &bbr_rttprobe_gain, 192,
1188 "What is the filter gain drop in probe_rtt (0=disable)?");
1189 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1190 SYSCTL_CHILDREN(bbr_probertt),
1191 OID_AUTO, "cwnd", CTLFLAG_RW,
1192 &bbr_rtt_probe_cwndtarg, 4,
1193 "How many mss's are outstanding during probe-rtt");
1194 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1195 SYSCTL_CHILDREN(bbr_probertt),
1196 OID_AUTO, "int", CTLFLAG_RW,
1197 &bbr_rtt_probe_limit, 4000000,
1198 "If RTT has not shrank in this many micro-seconds enter probe-rtt");
1199 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1200 SYSCTL_CHILDREN(bbr_probertt),
1201 OID_AUTO, "mintime", CTLFLAG_RW,
1202 &bbr_rtt_probe_time, 200000,
1203 "How many microseconds in probe-rtt");
1204 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1205 SYSCTL_CHILDREN(bbr_probertt),
1206 OID_AUTO, "filter_len_sec", CTLFLAG_RW,
1207 &bbr_filter_len_sec, 6,
1208 "How long in seconds does the rttProp filter run?");
1209 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1210 SYSCTL_CHILDREN(bbr_probertt),
1211 OID_AUTO, "drain_rtt", CTLFLAG_RW,
1212 &bbr_drain_rtt, BBR_SRTT,
1213 "What is the drain rtt to use in probeRTT (rtt_prop=0, rtt_rack=1, rtt_pkt=2, rtt_srtt=3?");
1214 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1215 SYSCTL_CHILDREN(bbr_probertt),
1216 OID_AUTO, "can_force", CTLFLAG_RW,
1217 &bbr_can_force_probertt, 0,
1218 "If we keep setting new low rtt's but delay going in probe-rtt can we force in??");
1219 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1220 SYSCTL_CHILDREN(bbr_probertt),
1221 OID_AUTO, "enter_sets_force", CTLFLAG_RW,
1222 &bbr_probertt_sets_rtt, 0,
1223 "In NF mode, do we imitate google_mode and set the rttProp on entry to probe-rtt?");
1224 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1225 SYSCTL_CHILDREN(bbr_probertt),
1226 OID_AUTO, "can_adjust", CTLFLAG_RW,
1227 &bbr_can_adjust_probertt, 1,
1228 "Can we dynamically adjust the probe-rtt limits and times?");
1229 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1230 SYSCTL_CHILDREN(bbr_probertt),
1231 OID_AUTO, "is_ratio", CTLFLAG_RW,
1232 &bbr_is_ratio, 0,
1233 "is the limit to filter a ratio?");
1234 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1235 SYSCTL_CHILDREN(bbr_probertt),
1236 OID_AUTO, "use_cwnd", CTLFLAG_RW,
1237 &bbr_prtt_slam_cwnd, 0,
1238 "Should we set/recover cwnd?");
1239 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1240 SYSCTL_CHILDREN(bbr_probertt),
1241 OID_AUTO, "can_use_ts", CTLFLAG_RW,
1242 &bbr_can_use_ts_for_rtt, 1,
1243 "Can we use the ms timestamp if available for retransmistted rtt calculations?");
1244
1245 /* Pacing controls */
1246 bbr_hptsi = SYSCTL_ADD_NODE(&bbr_sysctl_ctx,
1247 SYSCTL_CHILDREN(bbr_sysctl_root),
1248 OID_AUTO,
1249 "pacing",
1250 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1251 "");
1252 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1253 SYSCTL_CHILDREN(bbr_hptsi),
1254 OID_AUTO, "hw_pacing", CTLFLAG_RW,
1255 &bbr_allow_hdwr_pacing, 1,
1256 "Do we allow hardware pacing?");
1257 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1258 SYSCTL_CHILDREN(bbr_hptsi),
1259 OID_AUTO, "hw_pacing_limit", CTLFLAG_RW,
1260 &bbr_hardware_pacing_limit, 4000,
1261 "Do we have a limited number of connections for pacing chelsio (0=no limit)?");
1262 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1263 SYSCTL_CHILDREN(bbr_hptsi),
1264 OID_AUTO, "hw_pacing_adj", CTLFLAG_RW,
1265 &bbr_hdwr_pace_adjust, 2,
1266 "Multiplier to calculated tso size?");
1267 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1268 SYSCTL_CHILDREN(bbr_hptsi),
1269 OID_AUTO, "hw_pacing_floor", CTLFLAG_RW,
1270 &bbr_hdwr_pace_floor, 1,
1271 "Do we invoke the hardware pacing floor?");
1272 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1273 SYSCTL_CHILDREN(bbr_hptsi),
1274 OID_AUTO, "hw_pacing_delay_cnt", CTLFLAG_RW,
1275 &bbr_hdwr_pacing_delay_cnt, 10,
1276 "How many packets must be sent after hdwr pacing is enabled");
1277 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1278 SYSCTL_CHILDREN(bbr_hptsi),
1279 OID_AUTO, "bw_cross", CTLFLAG_RW,
1280 &bbr_cross_over, 3000000,
1281 "What is the point where we cross over to linux like TSO size set");
1282 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1283 SYSCTL_CHILDREN(bbr_hptsi),
1284 OID_AUTO, "seg_deltarg", CTLFLAG_RW,
1285 &bbr_hptsi_segments_delay_tar, 7000,
1286 "What is the worse case delay target for hptsi < 48Mbp connections");
1287 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1288 SYSCTL_CHILDREN(bbr_hptsi),
1289 OID_AUTO, "enet_oh", CTLFLAG_RW,
1290 &bbr_include_enet_oh, 0,
1291 "Do we include the ethernet overhead in calculating pacing delay?");
1292 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1293 SYSCTL_CHILDREN(bbr_hptsi),
1294 OID_AUTO, "ip_oh", CTLFLAG_RW,
1295 &bbr_include_ip_oh, 1,
1296 "Do we include the IP overhead in calculating pacing delay?");
1297 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1298 SYSCTL_CHILDREN(bbr_hptsi),
1299 OID_AUTO, "tcp_oh", CTLFLAG_RW,
1300 &bbr_include_tcp_oh, 0,
1301 "Do we include the TCP overhead in calculating pacing delay?");
1302 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1303 SYSCTL_CHILDREN(bbr_hptsi),
1304 OID_AUTO, "google_discount", CTLFLAG_RW,
1305 &bbr_google_discount, 10,
1306 "What is the default google discount percentage wise for pacing (11 = 1.1%%)?");
1307 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1308 SYSCTL_CHILDREN(bbr_hptsi),
1309 OID_AUTO, "all_get_min", CTLFLAG_RW,
1310 &bbr_all_get_min, 0,
1311 "If you are less than a MSS do you just get the min?");
1312 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1313 SYSCTL_CHILDREN(bbr_hptsi),
1314 OID_AUTO, "tso_min", CTLFLAG_RW,
1315 &bbr_hptsi_bytes_min, 1460,
1316 "For 0 -> 24Mbps what is floor number of segments for TSO");
1317 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1318 SYSCTL_CHILDREN(bbr_hptsi),
1319 OID_AUTO, "seg_tso_max", CTLFLAG_RW,
1320 &bbr_hptsi_segments_max, 6,
1321 "For 0 -> 24Mbps what is top number of segments for TSO");
1322 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1323 SYSCTL_CHILDREN(bbr_hptsi),
1324 OID_AUTO, "seg_floor", CTLFLAG_RW,
1325 &bbr_hptsi_segments_floor, 1,
1326 "Minimum TSO size we will fall too in segments");
1327 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1328 SYSCTL_CHILDREN(bbr_hptsi),
1329 OID_AUTO, "utter_max", CTLFLAG_RW,
1330 &bbr_hptsi_utter_max, 0,
1331 "The absolute maximum that any pacing (outside of hardware) can be");
1332 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1333 SYSCTL_CHILDREN(bbr_hptsi),
1334 OID_AUTO, "seg_divisor", CTLFLAG_RW,
1335 &bbr_hptsi_per_second, 100,
1336 "What is the divisor in our hptsi TSO calculation 512Mbps < X > 24Mbps ");
1337 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1338 SYSCTL_CHILDREN(bbr_hptsi),
1339 OID_AUTO, "srtt_mul", CTLFLAG_RW,
1340 &bbr_hptsi_max_mul, 1,
1341 "The multiplier for pace len max");
1342 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1343 SYSCTL_CHILDREN(bbr_hptsi),
1344 OID_AUTO, "srtt_div", CTLFLAG_RW,
1345 &bbr_hptsi_max_div, 2,
1346 "The divisor for pace len max");
1347 /* Measurement controls */
1348 bbr_measure = SYSCTL_ADD_NODE(&bbr_sysctl_ctx,
1349 SYSCTL_CHILDREN(bbr_sysctl_root),
1350 OID_AUTO,
1351 "measure",
1352 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1353 "Measurement controls");
1354 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1355 SYSCTL_CHILDREN(bbr_measure),
1356 OID_AUTO, "min_i_bw", CTLFLAG_RW,
1357 &bbr_initial_bw_bps, 62500,
1358 "Minimum initial b/w in bytes per second");
1359 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1360 SYSCTL_CHILDREN(bbr_measure),
1361 OID_AUTO, "no_sack_needed", CTLFLAG_RW,
1362 &bbr_sack_not_required, 0,
1363 "Do we allow bbr to run on connections not supporting SACK?");
1364 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1365 SYSCTL_CHILDREN(bbr_measure),
1366 OID_AUTO, "use_google", CTLFLAG_RW,
1367 &bbr_use_google_algo, 0,
1368 "Use has close to google V1.0 has possible?");
1369 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1370 SYSCTL_CHILDREN(bbr_measure),
1371 OID_AUTO, "ts_limiting", CTLFLAG_RW,
1372 &bbr_ts_limiting, 1,
1373 "Do we attempt to use the peers timestamp to limit b/w caculations?");
1374 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1375 SYSCTL_CHILDREN(bbr_measure),
1376 OID_AUTO, "ts_can_raise", CTLFLAG_RW,
1377 &bbr_ts_can_raise, 0,
1378 "Can we raise the b/w via timestamp b/w calculation?");
1379 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1380 SYSCTL_CHILDREN(bbr_measure),
1381 OID_AUTO, "ts_delta", CTLFLAG_RW,
1382 &bbr_min_usec_delta, 20000,
1383 "How long in usec between ts of our sends in ts validation code?");
1384 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1385 SYSCTL_CHILDREN(bbr_measure),
1386 OID_AUTO, "ts_peer_delta", CTLFLAG_RW,
1387 &bbr_min_peer_delta, 20,
1388 "What min numerical value should be between the peer deltas?");
1389 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1390 SYSCTL_CHILDREN(bbr_measure),
1391 OID_AUTO, "ts_delta_percent", CTLFLAG_RW,
1392 &bbr_delta_percent, 150,
1393 "What percentage (150 = 15.0) do we allow variance for?");
1394 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1395 SYSCTL_CHILDREN(bbr_measure),
1396 OID_AUTO, "min_measure_good_bw", CTLFLAG_RW,
1397 &bbr_min_measurements_req, 1,
1398 "What is the minimum measurement count we need before we switch to our b/w estimate");
1399 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1400 SYSCTL_CHILDREN(bbr_measure),
1401 OID_AUTO, "min_measure_before_pace", CTLFLAG_RW,
1402 &bbr_no_pacing_until, 4,
1403 "How many pkt-epoch's (0 is off) do we need before pacing is on?");
1404 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1405 SYSCTL_CHILDREN(bbr_measure),
1406 OID_AUTO, "quanta", CTLFLAG_RW,
1407 &bbr_quanta, 2,
1408 "Extra quanta to add when calculating the target (ID section 4.2.3.2).");
1409 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1410 SYSCTL_CHILDREN(bbr_measure),
1411 OID_AUTO, "noretran", CTLFLAG_RW,
1412 &bbr_no_retran, 0,
1413 "Should google mode not use retransmission measurements for the b/w estimation?");
1414 /* State controls */
1415 bbr_states = SYSCTL_ADD_NODE(&bbr_sysctl_ctx,
1416 SYSCTL_CHILDREN(bbr_sysctl_root),
1417 OID_AUTO,
1418 "states",
1419 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1420 "State controls");
1421 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1422 SYSCTL_CHILDREN(bbr_states),
1423 OID_AUTO, "idle_restart", CTLFLAG_RW,
1424 &bbr_uses_idle_restart, 0,
1425 "Do we use a new special idle_restart state to ramp back up quickly?");
1426 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1427 SYSCTL_CHILDREN(bbr_states),
1428 OID_AUTO, "idle_restart_threshold", CTLFLAG_RW,
1429 &bbr_idle_restart_threshold, 100000,
1430 "How long must we be idle before we restart??");
1431 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1432 SYSCTL_CHILDREN(bbr_states),
1433 OID_AUTO, "use_pkt_epoch", CTLFLAG_RW,
1434 &bbr_state_is_pkt_epoch, 0,
1435 "Do we use a pkt-epoch for substate if 0 rttProp?");
1436 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1437 SYSCTL_CHILDREN(bbr_states),
1438 OID_AUTO, "startup_rtt_gain", CTLFLAG_RW,
1439 &bbr_rtt_gain_thresh, 0,
1440 "What increase in RTT triggers us to stop ignoring no-loss and possibly exit startup?");
1441 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1442 SYSCTL_CHILDREN(bbr_states),
1443 OID_AUTO, "drain_floor", CTLFLAG_RW,
1444 &bbr_drain_floor, 88,
1445 "What is the lowest we can drain (pg) too?");
1446 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1447 SYSCTL_CHILDREN(bbr_states),
1448 OID_AUTO, "drain_2_target", CTLFLAG_RW,
1449 &bbr_state_drain_2_tar, 1,
1450 "Do we drain to target in drain substate?");
1451 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1452 SYSCTL_CHILDREN(bbr_states),
1453 OID_AUTO, "gain_2_target", CTLFLAG_RW,
1454 &bbr_gain_to_target, 1,
1455 "Does probe bw gain to target??");
1456 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1457 SYSCTL_CHILDREN(bbr_states),
1458 OID_AUTO, "gain_extra_time", CTLFLAG_RW,
1459 &bbr_gain_gets_extra_too, 1,
1460 "Does probe bw gain get the extra time too?");
1461 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1462 SYSCTL_CHILDREN(bbr_states),
1463 OID_AUTO, "ld_div", CTLFLAG_RW,
1464 &bbr_drain_drop_div, 5,
1465 "Long drain drop divider?");
1466 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1467 SYSCTL_CHILDREN(bbr_states),
1468 OID_AUTO, "ld_mul", CTLFLAG_RW,
1469 &bbr_drain_drop_mul, 4,
1470 "Long drain drop multiplier?");
1471 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1472 SYSCTL_CHILDREN(bbr_states),
1473 OID_AUTO, "rand_ot_disc", CTLFLAG_RW,
1474 &bbr_rand_ot, 50,
1475 "Random discount of the ot?");
1476 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1477 SYSCTL_CHILDREN(bbr_states),
1478 OID_AUTO, "dr_filter_life", CTLFLAG_RW,
1479 &bbr_num_pktepo_for_del_limit, BBR_NUM_RTTS_FOR_DEL_LIMIT,
1480 "How many packet-epochs does the b/w delivery rate last?");
1481 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1482 SYSCTL_CHILDREN(bbr_states),
1483 OID_AUTO, "subdrain_applimited", CTLFLAG_RW,
1484 &bbr_sub_drain_app_limit, 0,
1485 "Does our sub-state drain invoke app limited if its long?");
1486 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1487 SYSCTL_CHILDREN(bbr_states),
1488 OID_AUTO, "use_cwnd_subdrain", CTLFLAG_RW,
1489 &bbr_sub_drain_slam_cwnd, 0,
1490 "Should we set/recover cwnd for sub-state drain?");
1491 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1492 SYSCTL_CHILDREN(bbr_states),
1493 OID_AUTO, "use_cwnd_maindrain", CTLFLAG_RW,
1494 &bbr_slam_cwnd_in_main_drain, 0,
1495 "Should we set/recover cwnd for main-state drain?");
1496 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1497 SYSCTL_CHILDREN(bbr_states),
1498 OID_AUTO, "google_gets_earlyout", CTLFLAG_RW,
1499 &google_allow_early_out, 1,
1500 "Should we allow google probe-bw/drain to exit early at flight target?");
1501 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1502 SYSCTL_CHILDREN(bbr_states),
1503 OID_AUTO, "google_exit_loss", CTLFLAG_RW,
1504 &google_consider_lost, 1,
1505 "Should we have losses exit gain of probebw in google mode??");
1506 /* Startup controls */
1507 bbr_startup = SYSCTL_ADD_NODE(&bbr_sysctl_ctx,
1508 SYSCTL_CHILDREN(bbr_sysctl_root),
1509 OID_AUTO,
1510 "startup",
1511 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1512 "Startup controls");
1513 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1514 SYSCTL_CHILDREN(bbr_startup),
1515 OID_AUTO, "cheat_iwnd", CTLFLAG_RW,
1516 &bbr_sends_full_iwnd, 1,
1517 "Do we not pace but burst out initial windows has our TSO size?");
1518 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1519 SYSCTL_CHILDREN(bbr_startup),
1520 OID_AUTO, "loss_threshold", CTLFLAG_RW,
1521 &bbr_startup_loss_thresh, 2000,
1522 "In startup what is the loss threshold in a pe that will exit us from startup?");
1523 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1524 SYSCTL_CHILDREN(bbr_startup),
1525 OID_AUTO, "use_lowerpg", CTLFLAG_RW,
1526 &bbr_use_lower_gain_in_startup, 1,
1527 "Should we use a lower hptsi gain if we see loss in startup?");
1528 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1529 SYSCTL_CHILDREN(bbr_startup),
1530 OID_AUTO, "gain", CTLFLAG_RW,
1531 &bbr_start_exit, 25,
1532 "What gain percent do we need to see to stay in startup??");
1533 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1534 SYSCTL_CHILDREN(bbr_startup),
1535 OID_AUTO, "low_gain", CTLFLAG_RW,
1536 &bbr_low_start_exit, 15,
1537 "What gain percent do we need to see to stay in the lower gain startup??");
1538 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1539 SYSCTL_CHILDREN(bbr_startup),
1540 OID_AUTO, "loss_exit", CTLFLAG_RW,
1541 &bbr_exit_startup_at_loss, 1,
1542 "Should we exit startup at loss in an epoch if we are not gaining?");
1543 /* CWND controls */
1544 bbr_cwnd = SYSCTL_ADD_NODE(&bbr_sysctl_ctx,
1545 SYSCTL_CHILDREN(bbr_sysctl_root),
1546 OID_AUTO,
1547 "cwnd",
1548 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1549 "Cwnd controls");
1550 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1551 SYSCTL_CHILDREN(bbr_cwnd),
1552 OID_AUTO, "tar_rtt", CTLFLAG_RW,
1553 &bbr_cwndtarget_rtt_touse, 0,
1554 "Target cwnd rtt measurement to use (0=rtt_prop, 1=rtt_rack, 2=pkt_rtt, 3=srtt)?");
1555 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1556 SYSCTL_CHILDREN(bbr_cwnd),
1557 OID_AUTO, "may_shrink", CTLFLAG_RW,
1558 &bbr_cwnd_may_shrink, 0,
1559 "Can the cwnd shrink if it would grow to more than the target?");
1560 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1561 SYSCTL_CHILDREN(bbr_cwnd),
1562 OID_AUTO, "max_target_limit", CTLFLAG_RW,
1563 &bbr_target_cwnd_mult_limit, 8,
1564 "Do we limit the cwnd to some multiple of the cwnd target if cwnd can't shrink 0=no?");
1565 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1566 SYSCTL_CHILDREN(bbr_cwnd),
1567 OID_AUTO, "highspeed_min", CTLFLAG_RW,
1568 &bbr_cwnd_min_val_hs, BBR_HIGHSPEED_NUM_MSS,
1569 "What is the high-speed min cwnd (rttProp under 1ms)");
1570 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1571 SYSCTL_CHILDREN(bbr_cwnd),
1572 OID_AUTO, "lowspeed_min", CTLFLAG_RW,
1573 &bbr_cwnd_min_val, BBR_PROBERTT_NUM_MSS,
1574 "What is the min cwnd (rttProp > 1ms)");
1575 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1576 SYSCTL_CHILDREN(bbr_cwnd),
1577 OID_AUTO, "initwin", CTLFLAG_RW,
1578 &bbr_def_init_win, 10,
1579 "What is the BBR initial window, if 0 use tcp version");
1580 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1581 SYSCTL_CHILDREN(bbr_cwnd),
1582 OID_AUTO, "do_loss_red", CTLFLAG_RW,
1583 &bbr_do_red, 600,
1584 "Do we reduce the b/w at exit from recovery based on ratio of prop/srtt (800=80.0, 0=off)?");
1585 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1586 SYSCTL_CHILDREN(bbr_cwnd),
1587 OID_AUTO, "red_scale", CTLFLAG_RW,
1588 &bbr_red_scale, 20000,
1589 "What RTT do we scale with?");
1590 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1591 SYSCTL_CHILDREN(bbr_cwnd),
1592 OID_AUTO, "red_growslow", CTLFLAG_RW,
1593 &bbr_red_growth_restrict, 1,
1594 "Do we restrict cwnd growth for whats in flight?");
1595 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1596 SYSCTL_CHILDREN(bbr_cwnd),
1597 OID_AUTO, "red_div", CTLFLAG_RW,
1598 &bbr_red_div, 2,
1599 "If we reduce whats the divisor?");
1600 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1601 SYSCTL_CHILDREN(bbr_cwnd),
1602 OID_AUTO, "red_mul", CTLFLAG_RW,
1603 &bbr_red_mul, 1,
1604 "If we reduce whats the mulitiplier?");
1605 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1606 SYSCTL_CHILDREN(bbr_cwnd),
1607 OID_AUTO, "target_is_unit", CTLFLAG_RW,
1608 &bbr_target_is_bbunit, 0,
1609 "Is the state target the pacing_gain or BBR_UNIT?");
1610 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1611 SYSCTL_CHILDREN(bbr_cwnd),
1612 OID_AUTO, "drop_limit", CTLFLAG_RW,
1613 &bbr_drop_limit, 0,
1614 "Number of segments limit for drop (0=use min_cwnd w/flight)?");
1615
1616 /* Timeout controls */
1617 bbr_timeout = SYSCTL_ADD_NODE(&bbr_sysctl_ctx,
1618 SYSCTL_CHILDREN(bbr_sysctl_root),
1619 OID_AUTO,
1620 "timeout",
1621 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1622 "Time out controls");
1623 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1624 SYSCTL_CHILDREN(bbr_timeout),
1625 OID_AUTO, "delack", CTLFLAG_RW,
1626 &bbr_delack_time, 100000,
1627 "BBR's delayed ack time");
1628 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1629 SYSCTL_CHILDREN(bbr_timeout),
1630 OID_AUTO, "tlp_uses", CTLFLAG_RW,
1631 &bbr_tlp_type_to_use, 3,
1632 "RTT that TLP uses in its calculations, 0=rttProp, 1=Rack_rtt, 2=pkt_rtt and 3=srtt");
1633 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1634 SYSCTL_CHILDREN(bbr_timeout),
1635 OID_AUTO, "persmin", CTLFLAG_RW,
1636 &bbr_persist_min, 250000,
1637 "What is the minimum time in microseconds between persists");
1638 SYSCTL_ADD_U32(&bbr_sysctl_ctx,
1639 SYSCTL_CHILDREN(bbr_timeout),
1640 OID_AUTO, "persmax", CTLFLAG_RW,
1641 &bbr_persist_max, 1000000,
1642 "What is the largest delay in microseconds between persists");
1643 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1644 SYSCTL_CHILDREN(bbr_timeout),
1645 OID_AUTO, "tlp_minto", CTLFLAG_RW,
1646 &bbr_tlp_min, 10000,
1647 "TLP Min timeout in usecs");
1648 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1649 SYSCTL_CHILDREN(bbr_timeout),
1650 OID_AUTO, "tlp_dack_time", CTLFLAG_RW,
1651 &bbr_delayed_ack_time, 200000,
1652 "TLP delayed ack compensation value");
1653 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1654 SYSCTL_CHILDREN(bbr_sysctl_root),
1655 OID_AUTO, "minrto", CTLFLAG_RW,
1656 &bbr_rto_min_ms, 30,
1657 "Minimum RTO in ms");
1658 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1659 SYSCTL_CHILDREN(bbr_timeout),
1660 OID_AUTO, "maxrto", CTLFLAG_RW,
1661 &bbr_rto_max_sec, 4,
1662 "Maximum RTO in seconds -- should be at least as large as min_rto");
1663 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1664 SYSCTL_CHILDREN(bbr_timeout),
1665 OID_AUTO, "tlp_retry", CTLFLAG_RW,
1666 &bbr_tlp_max_resend, 2,
1667 "How many times does TLP retry a single segment or multiple with no ACK");
1668 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1669 SYSCTL_CHILDREN(bbr_timeout),
1670 OID_AUTO, "minto", CTLFLAG_RW,
1671 &bbr_min_to, 1000,
1672 "Minimum rack timeout in useconds");
1673 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1674 SYSCTL_CHILDREN(bbr_timeout),
1675 OID_AUTO, "pktdelay", CTLFLAG_RW,
1676 &bbr_pkt_delay, 1000,
1677 "Extra RACK time (in useconds) besides reordering thresh");
1678 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1679 SYSCTL_CHILDREN(bbr_timeout),
1680 OID_AUTO, "incr_tmrs", CTLFLAG_RW,
1681 &bbr_incr_timers, 1,
1682 "Increase the RXT/TLP timer by the pacing time used?");
1683 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1684 SYSCTL_CHILDREN(bbr_timeout),
1685 OID_AUTO, "rxtmark_sackpassed", CTLFLAG_RW,
1686 &bbr_marks_rxt_sack_passed, 0,
1687 "Mark sack passed on all those not ack'd when a RXT hits?");
1688 /* Policer controls */
1689 bbr_policer = SYSCTL_ADD_NODE(&bbr_sysctl_ctx,
1690 SYSCTL_CHILDREN(bbr_sysctl_root),
1691 OID_AUTO,
1692 "policer",
1693 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
1694 "Policer controls");
1695 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1696 SYSCTL_CHILDREN(bbr_policer),
1697 OID_AUTO, "detect_enable", CTLFLAG_RW,
1698 &bbr_policer_detection_enabled, 1,
1699 "Is policer detection enabled??");
1700 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1701 SYSCTL_CHILDREN(bbr_policer),
1702 OID_AUTO, "min_pes", CTLFLAG_RW,
1703 &bbr_lt_intvl_min_rtts, 4,
1704 "Minimum number of PE's?");
1705 SYSCTL_ADD_U64(&bbr_sysctl_ctx,
1706 SYSCTL_CHILDREN(bbr_policer),
1707 OID_AUTO, "bwdiff", CTLFLAG_RW,
1708 &bbr_lt_bw_diff, (4000/8),
1709 "Minimal bw diff?");
1710 SYSCTL_ADD_U64(&bbr_sysctl_ctx,
1711 SYSCTL_CHILDREN(bbr_policer),
1712 OID_AUTO, "bwratio", CTLFLAG_RW,
1713 &bbr_lt_bw_ratio, 8,
1714 "Minimal bw diff?");
1715 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1716 SYSCTL_CHILDREN(bbr_policer),
1717 OID_AUTO, "from_rack_rxt", CTLFLAG_RW,
1718 &bbr_policer_call_from_rack_to, 0,
1719 "Do we call the policer detection code from a rack-timeout?");
1720 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1721 SYSCTL_CHILDREN(bbr_policer),
1722 OID_AUTO, "false_postive", CTLFLAG_RW,
1723 &bbr_lt_intvl_fp, 0,
1724 "What packet epoch do we do false-positive detection at (0=no)?");
1725 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1726 SYSCTL_CHILDREN(bbr_policer),
1727 OID_AUTO, "loss_thresh", CTLFLAG_RW,
1728 &bbr_lt_loss_thresh, 196,
1729 "Loss threshold 196 = 19.6%?");
1730 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1731 SYSCTL_CHILDREN(bbr_policer),
1732 OID_AUTO, "false_postive_thresh", CTLFLAG_RW,
1733 &bbr_lt_fd_thresh, 100,
1734 "What percentage is the false detection threshold (150=15.0)?");
1735 /* All the rest */
1736 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1737 SYSCTL_CHILDREN(bbr_sysctl_root),
1738 OID_AUTO, "cheat_rxt", CTLFLAG_RW,
1739 &bbr_use_rack_resend_cheat, 0,
1740 "Do we burst 1ms between sends on retransmissions (like rack)?");
1741 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1742 SYSCTL_CHILDREN(bbr_sysctl_root),
1743 OID_AUTO, "error_paceout", CTLFLAG_RW,
1744 &bbr_error_base_paceout, 10000,
1745 "When we hit an error what is the min to pace out in usec's?");
1746 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1747 SYSCTL_CHILDREN(bbr_sysctl_root),
1748 OID_AUTO, "kill_paceout", CTLFLAG_RW,
1749 &bbr_max_net_error_cnt, 10,
1750 "When we hit this many errors in a row, kill the session?");
1751 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1752 SYSCTL_CHILDREN(bbr_sysctl_root),
1753 OID_AUTO, "data_after_close", CTLFLAG_RW,
1754 &bbr_ignore_data_after_close, 1,
1755 "Do we hold off sending a RST until all pending data is ack'd");
1756 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1757 SYSCTL_CHILDREN(bbr_sysctl_root),
1758 OID_AUTO, "resend_use_tso", CTLFLAG_RW,
1759 &bbr_resends_use_tso, 0,
1760 "Can resends use TSO?");
1761 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1762 SYSCTL_CHILDREN(bbr_sysctl_root),
1763 OID_AUTO, "sblklimit", CTLFLAG_RW,
1764 &bbr_sack_block_limit, 128,
1765 "When do we start ignoring small sack blocks");
1766 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1767 SYSCTL_CHILDREN(bbr_sysctl_root),
1768 OID_AUTO, "bb_verbose", CTLFLAG_RW,
1769 &bbr_verbose_logging, 0,
1770 "Should BBR black box logging be verbose");
1771 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1772 SYSCTL_CHILDREN(bbr_sysctl_root),
1773 OID_AUTO, "reorder_thresh", CTLFLAG_RW,
1774 &bbr_reorder_thresh, 2,
1775 "What factor for rack will be added when seeing reordering (shift right)");
1776 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1777 SYSCTL_CHILDREN(bbr_sysctl_root),
1778 OID_AUTO, "reorder_fade", CTLFLAG_RW,
1779 &bbr_reorder_fade, 0,
1780 "Does reorder detection fade, if so how many ms (0 means never)");
1781 SYSCTL_ADD_S32(&bbr_sysctl_ctx,
1782 SYSCTL_CHILDREN(bbr_sysctl_root),
1783 OID_AUTO, "rtt_tlp_thresh", CTLFLAG_RW,
1784 &bbr_tlp_thresh, 1,
1785 "what divisor for TLP rtt/retran will be added (1=rtt, 2=1/2 rtt etc)");
1786 /* Stats and counters */
1787 /* The pacing counters for hdwr/software can't be in the array */
1788 bbr_nohdwr_pacing_enobuf = counter_u64_alloc(M_WAITOK);
1789 bbr_hdwr_pacing_enobuf = counter_u64_alloc(M_WAITOK);
1790 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx,
1791 SYSCTL_CHILDREN(bbr_sysctl_root),
1792 OID_AUTO, "enob_hdwr_pacing", CTLFLAG_RD,
1793 &bbr_hdwr_pacing_enobuf,
1794 "Total number of enobufs for hardware paced flows");
1795 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx,
1796 SYSCTL_CHILDREN(bbr_sysctl_root),
1797 OID_AUTO, "enob_no_hdwr_pacing", CTLFLAG_RD,
1798 &bbr_nohdwr_pacing_enobuf,
1799 "Total number of enobufs for non-hardware paced flows");
1800
1801 bbr_flows_whdwr_pacing = counter_u64_alloc(M_WAITOK);
1802 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx,
1803 SYSCTL_CHILDREN(bbr_sysctl_root),
1804 OID_AUTO, "hdwr_pacing", CTLFLAG_RD,
1805 &bbr_flows_whdwr_pacing,
1806 "Total number of hardware paced flows");
1807 bbr_flows_nohdwr_pacing = counter_u64_alloc(M_WAITOK);
1808 SYSCTL_ADD_COUNTER_U64(&bbr_sysctl_ctx,
1809 SYSCTL_CHILDREN(bbr_sysctl_root),
1810 OID_AUTO, "software_pacing", CTLFLAG_RD,
1811 &bbr_flows_nohdwr_pacing,
1812 "Total number of software paced flows");
1813 COUNTER_ARRAY_ALLOC(bbr_stat_arry, BBR_STAT_SIZE, M_WAITOK);
1814 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root),
1815 OID_AUTO, "stats", CTLFLAG_RD,
1816 bbr_stat_arry, BBR_STAT_SIZE, "BBR Stats");
1817 COUNTER_ARRAY_ALLOC(bbr_opts_arry, BBR_OPTS_SIZE, M_WAITOK);
1818 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root),
1819 OID_AUTO, "opts", CTLFLAG_RD,
1820 bbr_opts_arry, BBR_OPTS_SIZE, "BBR Option Stats");
1821 COUNTER_ARRAY_ALLOC(bbr_state_lost, BBR_MAX_STAT, M_WAITOK);
1822 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root),
1823 OID_AUTO, "lost", CTLFLAG_RD,
1824 bbr_state_lost, BBR_MAX_STAT, "Stats of when losses occur");
1825 COUNTER_ARRAY_ALLOC(bbr_state_resend, BBR_MAX_STAT, M_WAITOK);
1826 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root),
1827 OID_AUTO, "stateresend", CTLFLAG_RD,
1828 bbr_state_resend, BBR_MAX_STAT, "Stats of what states resend");
1829 COUNTER_ARRAY_ALLOC(bbr_state_time, BBR_MAX_STAT, M_WAITOK);
1830 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root),
1831 OID_AUTO, "statetime", CTLFLAG_RD,
1832 bbr_state_time, BBR_MAX_STAT, "Stats of time spent in the states");
1833 COUNTER_ARRAY_ALLOC(bbr_out_size, TCP_MSS_ACCT_SIZE, M_WAITOK);
1834 SYSCTL_ADD_COUNTER_U64_ARRAY(&bbr_sysctl_ctx, SYSCTL_CHILDREN(bbr_sysctl_root),
1835 OID_AUTO, "outsize", CTLFLAG_RD,
1836 bbr_out_size, TCP_MSS_ACCT_SIZE, "Size of output calls");
1837 SYSCTL_ADD_PROC(&bbr_sysctl_ctx,
1838 SYSCTL_CHILDREN(bbr_sysctl_root),
1839 OID_AUTO, "clrlost", CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_MPSAFE,
1840 &bbr_clear_lost, 0, sysctl_bbr_clear_lost, "IU", "Clear lost counters");
1841 }
1842
1843 static void
1844 bbr_counter_destroy(void)
1845 {
1846 COUNTER_ARRAY_FREE(bbr_stat_arry, BBR_STAT_SIZE);
1847 COUNTER_ARRAY_FREE(bbr_opts_arry, BBR_OPTS_SIZE);
1848 COUNTER_ARRAY_FREE(bbr_out_size, TCP_MSS_ACCT_SIZE);
1849 COUNTER_ARRAY_FREE(bbr_state_lost, BBR_MAX_STAT);
1850 COUNTER_ARRAY_FREE(bbr_state_time, BBR_MAX_STAT);
1851 COUNTER_ARRAY_FREE(bbr_state_resend, BBR_MAX_STAT);
1852 counter_u64_free(bbr_nohdwr_pacing_enobuf);
1853 counter_u64_free(bbr_hdwr_pacing_enobuf);
1854 counter_u64_free(bbr_flows_whdwr_pacing);
1855 counter_u64_free(bbr_flows_nohdwr_pacing);
1856
1857 }
1858
1859 static __inline void
1860 bbr_fill_in_logging_data(struct tcp_bbr *bbr, struct tcp_log_bbr *l, uint32_t cts)
1861 {
1862 memset(l, 0, sizeof(union tcp_log_stackspecific));
1863 l->cur_del_rate = bbr->r_ctl.rc_bbr_cur_del_rate;
1864 l->delRate = get_filter_value(&bbr->r_ctl.rc_delrate);
1865 l->rttProp = get_filter_value_small(&bbr->r_ctl.rc_rttprop);
1866 l->bw_inuse = bbr_get_bw(bbr);
1867 l->inflight = ctf_flight_size(bbr->rc_tp,
1868 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
1869 l->applimited = bbr->r_ctl.r_app_limited_until;
1870 l->delivered = bbr->r_ctl.rc_delivered;
1871 l->timeStamp = cts;
1872 l->lost = bbr->r_ctl.rc_lost;
1873 l->bbr_state = bbr->rc_bbr_state;
1874 l->bbr_substate = bbr_state_val(bbr);
1875 l->epoch = bbr->r_ctl.rc_rtt_epoch;
1876 l->lt_epoch = bbr->r_ctl.rc_lt_epoch;
1877 l->pacing_gain = bbr->r_ctl.rc_bbr_hptsi_gain;
1878 l->cwnd_gain = bbr->r_ctl.rc_bbr_cwnd_gain;
1879 l->inhpts = tcp_in_hpts(bbr->rc_inp);
1880 l->use_lt_bw = bbr->rc_lt_use_bw;
1881 l->pkts_out = bbr->r_ctl.rc_flight_at_input;
1882 l->pkt_epoch = bbr->r_ctl.rc_pkt_epoch;
1883 }
1884
1885 static void
1886 bbr_log_type_bw_reduce(struct tcp_bbr *bbr, int reason)
1887 {
1888 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
1889 union tcp_log_stackspecific log;
1890
1891 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
1892 log.u_bbr.flex1 = 0;
1893 log.u_bbr.flex2 = 0;
1894 log.u_bbr.flex5 = 0;
1895 log.u_bbr.flex3 = 0;
1896 log.u_bbr.flex4 = bbr->r_ctl.rc_pkt_epoch_loss_rate;
1897 log.u_bbr.flex7 = reason;
1898 log.u_bbr.flex6 = bbr->r_ctl.rc_bbr_enters_probertt;
1899 log.u_bbr.flex8 = 0;
1900 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
1901 &bbr->rc_inp->inp_socket->so_rcv,
1902 &bbr->rc_inp->inp_socket->so_snd,
1903 BBR_LOG_BW_RED_EV, 0,
1904 0, &log, false, &bbr->rc_tv);
1905 }
1906 }
1907
1908 static void
1909 bbr_log_type_rwnd_collapse(struct tcp_bbr *bbr, int seq, int mode, uint32_t count)
1910 {
1911 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
1912 union tcp_log_stackspecific log;
1913
1914 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
1915 log.u_bbr.flex1 = seq;
1916 log.u_bbr.flex2 = count;
1917 log.u_bbr.flex8 = mode;
1918 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
1919 &bbr->rc_inp->inp_socket->so_rcv,
1920 &bbr->rc_inp->inp_socket->so_snd,
1921 BBR_LOG_LOWGAIN, 0,
1922 0, &log, false, &bbr->rc_tv);
1923 }
1924 }
1925
1926 static void
1927 bbr_log_type_just_return(struct tcp_bbr *bbr, uint32_t cts, uint32_t tlen, uint8_t hpts_calling,
1928 uint8_t reason, uint32_t p_maxseg, int len)
1929 {
1930 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
1931 union tcp_log_stackspecific log;
1932
1933 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
1934 log.u_bbr.flex1 = p_maxseg;
1935 log.u_bbr.flex2 = bbr->r_ctl.rc_hpts_flags;
1936 log.u_bbr.flex3 = bbr->r_ctl.rc_timer_exp;
1937 log.u_bbr.flex4 = reason;
1938 log.u_bbr.flex5 = bbr->rc_in_persist;
1939 log.u_bbr.flex6 = bbr->r_ctl.rc_last_delay_val;
1940 log.u_bbr.flex7 = p_maxseg;
1941 log.u_bbr.flex8 = bbr->rc_in_persist;
1942 log.u_bbr.pkts_out = 0;
1943 log.u_bbr.applimited = len;
1944 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
1945 &bbr->rc_inp->inp_socket->so_rcv,
1946 &bbr->rc_inp->inp_socket->so_snd,
1947 BBR_LOG_JUSTRET, 0,
1948 tlen, &log, false, &bbr->rc_tv);
1949 }
1950 }
1951
1952 static void
1953 bbr_log_type_enter_rec(struct tcp_bbr *bbr, uint32_t seq)
1954 {
1955 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
1956 union tcp_log_stackspecific log;
1957
1958 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
1959 log.u_bbr.flex1 = seq;
1960 log.u_bbr.flex2 = bbr->r_ctl.rc_cwnd_on_ent;
1961 log.u_bbr.flex3 = bbr->r_ctl.rc_recovery_start;
1962 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
1963 &bbr->rc_inp->inp_socket->so_rcv,
1964 &bbr->rc_inp->inp_socket->so_snd,
1965 BBR_LOG_ENTREC, 0,
1966 0, &log, false, &bbr->rc_tv);
1967 }
1968 }
1969
1970 static void
1971 bbr_log_msgsize_fail(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t len, uint32_t maxseg, uint32_t mtu, int32_t csum_flags, int32_t tso, uint32_t cts)
1972 {
1973 if (tp->t_logstate != TCP_LOG_STATE_OFF) {
1974 union tcp_log_stackspecific log;
1975
1976 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
1977 log.u_bbr.flex1 = tso;
1978 log.u_bbr.flex2 = maxseg;
1979 log.u_bbr.flex3 = mtu;
1980 log.u_bbr.flex4 = csum_flags;
1981 TCP_LOG_EVENTP(tp, NULL,
1982 &bbr->rc_inp->inp_socket->so_rcv,
1983 &bbr->rc_inp->inp_socket->so_snd,
1984 BBR_LOG_MSGSIZE, 0,
1985 0, &log, false, &bbr->rc_tv);
1986 }
1987 }
1988
1989 static void
1990 bbr_log_flowend(struct tcp_bbr *bbr)
1991 {
1992 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
1993 union tcp_log_stackspecific log;
1994 struct sockbuf *r, *s;
1995 struct timeval tv;
1996
1997 if (bbr->rc_inp->inp_socket) {
1998 r = &bbr->rc_inp->inp_socket->so_rcv;
1999 s = &bbr->rc_inp->inp_socket->so_snd;
2000 } else {
2001 r = s = NULL;
2002 }
2003 bbr_fill_in_logging_data(bbr, &log.u_bbr, tcp_get_usecs(&tv));
2004 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2005 r, s,
2006 TCP_LOG_FLOWEND, 0,
2007 0, &log, false, &tv);
2008 }
2009 }
2010
2011 static void
2012 bbr_log_pkt_epoch(struct tcp_bbr *bbr, uint32_t cts, uint32_t line,
2013 uint32_t lost, uint32_t del)
2014 {
2015 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2016 union tcp_log_stackspecific log;
2017
2018 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2019 log.u_bbr.flex1 = lost;
2020 log.u_bbr.flex2 = del;
2021 log.u_bbr.flex3 = bbr->r_ctl.rc_bbr_lastbtlbw;
2022 log.u_bbr.flex4 = bbr->r_ctl.rc_pkt_epoch_rtt;
2023 log.u_bbr.flex5 = bbr->r_ctl.rc_bbr_last_startup_epoch;
2024 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_at_startup;
2025 log.u_bbr.flex7 = line;
2026 log.u_bbr.flex8 = 0;
2027 log.u_bbr.inflight = bbr->r_ctl.r_measurement_count;
2028 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2029 &bbr->rc_inp->inp_socket->so_rcv,
2030 &bbr->rc_inp->inp_socket->so_snd,
2031 BBR_LOG_PKT_EPOCH, 0,
2032 0, &log, false, &bbr->rc_tv);
2033 }
2034 }
2035
2036 static void
2037 bbr_log_time_epoch(struct tcp_bbr *bbr, uint32_t cts, uint32_t line, uint32_t epoch_time)
2038 {
2039 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2040 union tcp_log_stackspecific log;
2041
2042 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2043 log.u_bbr.flex1 = bbr->r_ctl.rc_lost;
2044 log.u_bbr.flex2 = bbr->rc_inp->inp_socket->so_snd.sb_lowat;
2045 log.u_bbr.flex3 = bbr->rc_inp->inp_socket->so_snd.sb_hiwat;
2046 log.u_bbr.flex7 = line;
2047 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2048 &bbr->rc_inp->inp_socket->so_rcv,
2049 &bbr->rc_inp->inp_socket->so_snd,
2050 BBR_LOG_TIME_EPOCH, 0,
2051 0, &log, false, &bbr->rc_tv);
2052 }
2053 }
2054
2055 static void
2056 bbr_log_set_of_state_target(struct tcp_bbr *bbr, uint32_t new_tar, int line, int meth)
2057 {
2058 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2059 union tcp_log_stackspecific log;
2060
2061 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
2062 log.u_bbr.flex1 = bbr->r_ctl.rc_target_at_state;
2063 log.u_bbr.flex2 = new_tar;
2064 log.u_bbr.flex3 = line;
2065 log.u_bbr.flex4 = bbr->r_ctl.rc_pace_max_segs;
2066 log.u_bbr.flex5 = bbr_quanta;
2067 log.u_bbr.flex6 = bbr->r_ctl.rc_pace_min_segs;
2068 log.u_bbr.flex7 = bbr->rc_last_options;
2069 log.u_bbr.flex8 = meth;
2070 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2071 &bbr->rc_inp->inp_socket->so_rcv,
2072 &bbr->rc_inp->inp_socket->so_snd,
2073 BBR_LOG_STATE_TARGET, 0,
2074 0, &log, false, &bbr->rc_tv);
2075 }
2076
2077 }
2078
2079 static void
2080 bbr_log_type_statechange(struct tcp_bbr *bbr, uint32_t cts, int32_t line)
2081 {
2082 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2083 union tcp_log_stackspecific log;
2084
2085 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2086 log.u_bbr.flex1 = line;
2087 log.u_bbr.flex2 = bbr->r_ctl.rc_rtt_shrinks;
2088 log.u_bbr.flex3 = bbr->r_ctl.rc_probertt_int;
2089 if (bbr_state_is_pkt_epoch)
2090 log.u_bbr.flex4 = bbr_get_rtt(bbr, BBR_RTT_PKTRTT);
2091 else
2092 log.u_bbr.flex4 = bbr_get_rtt(bbr, BBR_RTT_PROP);
2093 log.u_bbr.flex5 = bbr->r_ctl.rc_bbr_last_startup_epoch;
2094 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_at_startup;
2095 log.u_bbr.flex7 = (bbr->r_ctl.rc_target_at_state/1000);
2096 log.u_bbr.lt_epoch = bbr->r_ctl.rc_level_state_extra;
2097 log.u_bbr.pkts_out = bbr->r_ctl.rc_target_at_state;
2098 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2099 &bbr->rc_inp->inp_socket->so_rcv,
2100 &bbr->rc_inp->inp_socket->so_snd,
2101 BBR_LOG_STATE, 0,
2102 0, &log, false, &bbr->rc_tv);
2103 }
2104 }
2105
2106 static void
2107 bbr_log_rtt_shrinks(struct tcp_bbr *bbr, uint32_t cts, uint32_t applied,
2108 uint32_t rtt, uint32_t line, uint8_t reas, uint16_t cond)
2109 {
2110 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2111 union tcp_log_stackspecific log;
2112
2113 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2114 log.u_bbr.flex1 = line;
2115 log.u_bbr.flex2 = bbr->r_ctl.rc_rtt_shrinks;
2116 log.u_bbr.flex3 = bbr->r_ctl.last_in_probertt;
2117 log.u_bbr.flex4 = applied;
2118 log.u_bbr.flex5 = rtt;
2119 log.u_bbr.flex6 = bbr->r_ctl.rc_target_at_state;
2120 log.u_bbr.flex7 = cond;
2121 log.u_bbr.flex8 = reas;
2122 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2123 &bbr->rc_inp->inp_socket->so_rcv,
2124 &bbr->rc_inp->inp_socket->so_snd,
2125 BBR_LOG_RTT_SHRINKS, 0,
2126 0, &log, false, &bbr->rc_tv);
2127 }
2128 }
2129
2130 static void
2131 bbr_log_type_exit_rec(struct tcp_bbr *bbr)
2132 {
2133 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2134 union tcp_log_stackspecific log;
2135
2136 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
2137 log.u_bbr.flex1 = bbr->r_ctl.rc_recovery_start;
2138 log.u_bbr.flex2 = bbr->r_ctl.rc_cwnd_on_ent;
2139 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state;
2140 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2141 &bbr->rc_inp->inp_socket->so_rcv,
2142 &bbr->rc_inp->inp_socket->so_snd,
2143 BBR_LOG_EXITREC, 0,
2144 0, &log, false, &bbr->rc_tv);
2145 }
2146 }
2147
2148 static void
2149 bbr_log_type_cwndupd(struct tcp_bbr *bbr, uint32_t bytes_this_ack, uint32_t chg,
2150 uint32_t prev_acked, int32_t meth, uint32_t target, uint32_t th_ack, int32_t line)
2151 {
2152 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2153 union tcp_log_stackspecific log;
2154
2155 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
2156 log.u_bbr.flex1 = line;
2157 log.u_bbr.flex2 = prev_acked;
2158 log.u_bbr.flex3 = bytes_this_ack;
2159 log.u_bbr.flex4 = chg;
2160 log.u_bbr.flex5 = th_ack;
2161 log.u_bbr.flex6 = target;
2162 log.u_bbr.flex8 = meth;
2163 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2164 &bbr->rc_inp->inp_socket->so_rcv,
2165 &bbr->rc_inp->inp_socket->so_snd,
2166 BBR_LOG_CWND, 0,
2167 0, &log, false, &bbr->rc_tv);
2168 }
2169 }
2170
2171 static void
2172 bbr_log_rtt_sample(struct tcp_bbr *bbr, uint32_t rtt, uint32_t tsin)
2173 {
2174 /*
2175 * Log the rtt sample we are applying to the srtt algorithm in
2176 * useconds.
2177 */
2178 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2179 union tcp_log_stackspecific log;
2180
2181 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
2182 log.u_bbr.flex1 = rtt;
2183 log.u_bbr.flex2 = bbr->r_ctl.rc_bbr_state_time;
2184 log.u_bbr.flex3 = bbr->r_ctl.rc_ack_hdwr_delay;
2185 log.u_bbr.flex4 = bbr->rc_tp->ts_offset;
2186 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state;
2187 log.u_bbr.pkts_out = tcp_tv_to_mssectick(&bbr->rc_tv);
2188 log.u_bbr.flex6 = tsin;
2189 log.u_bbr.flex7 = 0;
2190 log.u_bbr.flex8 = bbr->rc_ack_was_delayed;
2191 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2192 &bbr->rc_inp->inp_socket->so_rcv,
2193 &bbr->rc_inp->inp_socket->so_snd,
2194 TCP_LOG_RTT, 0,
2195 0, &log, false, &bbr->rc_tv);
2196 }
2197 }
2198
2199 static void
2200 bbr_log_type_pesist(struct tcp_bbr *bbr, uint32_t cts, uint32_t time_in, int32_t line, uint8_t enter_exit)
2201 {
2202 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2203 union tcp_log_stackspecific log;
2204
2205 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2206 log.u_bbr.flex1 = time_in;
2207 log.u_bbr.flex2 = line;
2208 log.u_bbr.flex8 = enter_exit;
2209 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2210 &bbr->rc_inp->inp_socket->so_rcv,
2211 &bbr->rc_inp->inp_socket->so_snd,
2212 BBR_LOG_PERSIST, 0,
2213 0, &log, false, &bbr->rc_tv);
2214 }
2215 }
2216 static void
2217 bbr_log_ack_clear(struct tcp_bbr *bbr, uint32_t cts)
2218 {
2219 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2220 union tcp_log_stackspecific log;
2221
2222 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2223 log.u_bbr.flex1 = bbr->rc_tp->ts_recent_age;
2224 log.u_bbr.flex2 = bbr->r_ctl.rc_rtt_shrinks;
2225 log.u_bbr.flex3 = bbr->r_ctl.rc_probertt_int;
2226 log.u_bbr.flex4 = bbr->r_ctl.rc_went_idle_time;
2227 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state;
2228 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2229 &bbr->rc_inp->inp_socket->so_rcv,
2230 &bbr->rc_inp->inp_socket->so_snd,
2231 BBR_LOG_ACKCLEAR, 0,
2232 0, &log, false, &bbr->rc_tv);
2233 }
2234 }
2235
2236 static void
2237 bbr_log_ack_event(struct tcp_bbr *bbr, struct tcphdr *th, struct tcpopt *to, uint32_t tlen,
2238 uint16_t nsegs, uint32_t cts, int32_t nxt_pkt, struct mbuf *m)
2239 {
2240 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2241 union tcp_log_stackspecific log;
2242 struct timeval tv;
2243
2244 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2245 log.u_bbr.flex1 = nsegs;
2246 log.u_bbr.flex2 = bbr->r_ctl.rc_lost_bytes;
2247 if (m) {
2248 struct timespec ts;
2249
2250 log.u_bbr.flex3 = m->m_flags;
2251 if (m->m_flags & M_TSTMP) {
2252 mbuf_tstmp2timespec(m, &ts);
2253 tv.tv_sec = ts.tv_sec;
2254 tv.tv_usec = ts.tv_nsec / 1000;
2255 log.u_bbr.lt_epoch = tcp_tv_to_usectick(&tv);
2256 } else {
2257 log.u_bbr.lt_epoch = 0;
2258 }
2259 if (m->m_flags & M_TSTMP_LRO) {
2260 mbuf_tstmp2timeval(m, &tv);
2261 log.u_bbr.flex5 = tcp_tv_to_usectick(&tv);
2262 } else {
2263 /* No arrival timestamp */
2264 log.u_bbr.flex5 = 0;
2265 }
2266
2267 log.u_bbr.pkts_out = tcp_get_usecs(&tv);
2268 } else {
2269 log.u_bbr.flex3 = 0;
2270 log.u_bbr.flex5 = 0;
2271 log.u_bbr.flex6 = 0;
2272 log.u_bbr.pkts_out = 0;
2273 }
2274 log.u_bbr.flex4 = bbr->r_ctl.rc_target_at_state;
2275 log.u_bbr.flex7 = bbr->r_wanted_output;
2276 log.u_bbr.flex8 = bbr->rc_in_persist;
2277 TCP_LOG_EVENTP(bbr->rc_tp, th,
2278 &bbr->rc_inp->inp_socket->so_rcv,
2279 &bbr->rc_inp->inp_socket->so_snd,
2280 TCP_LOG_IN, 0,
2281 tlen, &log, true, &bbr->rc_tv);
2282 }
2283 }
2284
2285 static void
2286 bbr_log_doseg_done(struct tcp_bbr *bbr, uint32_t cts, int32_t nxt_pkt, int32_t did_out)
2287 {
2288 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2289 union tcp_log_stackspecific log;
2290
2291 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2292 log.u_bbr.flex1 = did_out;
2293 log.u_bbr.flex2 = nxt_pkt;
2294 log.u_bbr.flex3 = bbr->r_ctl.rc_last_delay_val;
2295 log.u_bbr.flex4 = bbr->r_ctl.rc_hpts_flags;
2296 log.u_bbr.flex5 = bbr->r_ctl.rc_timer_exp;
2297 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_bytes;
2298 log.u_bbr.flex7 = bbr->r_wanted_output;
2299 log.u_bbr.flex8 = bbr->rc_in_persist;
2300 log.u_bbr.pkts_out = bbr->r_ctl.highest_hdwr_delay;
2301 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2302 &bbr->rc_inp->inp_socket->so_rcv,
2303 &bbr->rc_inp->inp_socket->so_snd,
2304 BBR_LOG_DOSEG_DONE, 0,
2305 0, &log, true, &bbr->rc_tv);
2306 }
2307 }
2308
2309 static void
2310 bbr_log_enobuf_jmp(struct tcp_bbr *bbr, uint32_t len, uint32_t cts,
2311 int32_t line, uint32_t o_len, uint32_t segcnt, uint32_t segsiz)
2312 {
2313 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2314 union tcp_log_stackspecific log;
2315
2316 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2317 log.u_bbr.flex1 = line;
2318 log.u_bbr.flex2 = o_len;
2319 log.u_bbr.flex3 = segcnt;
2320 log.u_bbr.flex4 = segsiz;
2321 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2322 &bbr->rc_inp->inp_socket->so_rcv,
2323 &bbr->rc_inp->inp_socket->so_snd,
2324 BBR_LOG_ENOBUF_JMP, ENOBUFS,
2325 len, &log, true, &bbr->rc_tv);
2326 }
2327 }
2328
2329 static void
2330 bbr_log_to_processing(struct tcp_bbr *bbr, uint32_t cts, int32_t ret, int32_t timers, uint8_t hpts_calling)
2331 {
2332 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2333 union tcp_log_stackspecific log;
2334
2335 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2336 log.u_bbr.flex1 = timers;
2337 log.u_bbr.flex2 = ret;
2338 log.u_bbr.flex3 = bbr->r_ctl.rc_timer_exp;
2339 log.u_bbr.flex4 = bbr->r_ctl.rc_hpts_flags;
2340 log.u_bbr.flex5 = cts;
2341 log.u_bbr.flex6 = bbr->r_ctl.rc_target_at_state;
2342 log.u_bbr.flex8 = hpts_calling;
2343 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2344 &bbr->rc_inp->inp_socket->so_rcv,
2345 &bbr->rc_inp->inp_socket->so_snd,
2346 BBR_LOG_TO_PROCESS, 0,
2347 0, &log, false, &bbr->rc_tv);
2348 }
2349 }
2350
2351 static void
2352 bbr_log_to_event(struct tcp_bbr *bbr, uint32_t cts, int32_t to_num)
2353 {
2354 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2355 union tcp_log_stackspecific log;
2356 uint64_t ar;
2357
2358 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2359 log.u_bbr.flex1 = bbr->bbr_timer_src;
2360 log.u_bbr.flex2 = 0;
2361 log.u_bbr.flex3 = bbr->r_ctl.rc_hpts_flags;
2362 ar = (uint64_t)(bbr->r_ctl.rc_resend);
2363 ar >>= 32;
2364 ar &= 0x00000000ffffffff;
2365 log.u_bbr.flex4 = (uint32_t)ar;
2366 ar = (uint64_t)bbr->r_ctl.rc_resend;
2367 ar &= 0x00000000ffffffff;
2368 log.u_bbr.flex5 = (uint32_t)ar;
2369 log.u_bbr.flex6 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur);
2370 log.u_bbr.flex8 = to_num;
2371 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2372 &bbr->rc_inp->inp_socket->so_rcv,
2373 &bbr->rc_inp->inp_socket->so_snd,
2374 BBR_LOG_RTO, 0,
2375 0, &log, false, &bbr->rc_tv);
2376 }
2377 }
2378
2379 static void
2380 bbr_log_startup_event(struct tcp_bbr *bbr, uint32_t cts, uint32_t flex1, uint32_t flex2, uint32_t flex3, uint8_t reason)
2381 {
2382 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2383 union tcp_log_stackspecific log;
2384
2385 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2386 log.u_bbr.flex1 = flex1;
2387 log.u_bbr.flex2 = flex2;
2388 log.u_bbr.flex3 = flex3;
2389 log.u_bbr.flex4 = 0;
2390 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state;
2391 log.u_bbr.flex6 = bbr->r_ctl.rc_lost_at_startup;
2392 log.u_bbr.flex8 = reason;
2393 log.u_bbr.cur_del_rate = bbr->r_ctl.rc_bbr_lastbtlbw;
2394 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2395 &bbr->rc_inp->inp_socket->so_rcv,
2396 &bbr->rc_inp->inp_socket->so_snd,
2397 BBR_LOG_REDUCE, 0,
2398 0, &log, false, &bbr->rc_tv);
2399 }
2400 }
2401
2402 static void
2403 bbr_log_hpts_diag(struct tcp_bbr *bbr, uint32_t cts, struct hpts_diag *diag)
2404 {
2405 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2406 union tcp_log_stackspecific log;
2407
2408 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2409 log.u_bbr.flex1 = diag->p_nxt_slot;
2410 log.u_bbr.flex2 = diag->p_cur_slot;
2411 log.u_bbr.flex3 = diag->slot_req;
2412 log.u_bbr.flex4 = diag->inp_hptsslot;
2413 log.u_bbr.flex5 = diag->slot_remaining;
2414 log.u_bbr.flex6 = diag->need_new_to;
2415 log.u_bbr.flex7 = diag->p_hpts_active;
2416 log.u_bbr.flex8 = diag->p_on_min_sleep;
2417 /* Hijack other fields as needed */
2418 log.u_bbr.epoch = diag->have_slept;
2419 log.u_bbr.lt_epoch = diag->yet_to_sleep;
2420 log.u_bbr.pkts_out = diag->co_ret;
2421 log.u_bbr.applimited = diag->hpts_sleep_time;
2422 log.u_bbr.delivered = diag->p_prev_slot;
2423 log.u_bbr.inflight = diag->p_runningslot;
2424 log.u_bbr.bw_inuse = diag->wheel_slot;
2425 log.u_bbr.rttProp = diag->wheel_cts;
2426 log.u_bbr.delRate = diag->maxslots;
2427 log.u_bbr.cur_del_rate = diag->p_curtick;
2428 log.u_bbr.cur_del_rate <<= 32;
2429 log.u_bbr.cur_del_rate |= diag->p_lasttick;
2430 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2431 &bbr->rc_inp->inp_socket->so_rcv,
2432 &bbr->rc_inp->inp_socket->so_snd,
2433 BBR_LOG_HPTSDIAG, 0,
2434 0, &log, false, &bbr->rc_tv);
2435 }
2436 }
2437
2438 static void
2439 bbr_log_timer_var(struct tcp_bbr *bbr, int mode, uint32_t cts, uint32_t time_since_sent, uint32_t srtt,
2440 uint32_t thresh, uint32_t to)
2441 {
2442 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2443 union tcp_log_stackspecific log;
2444
2445 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2446 log.u_bbr.flex1 = bbr->rc_tp->t_rttvar;
2447 log.u_bbr.flex2 = time_since_sent;
2448 log.u_bbr.flex3 = srtt;
2449 log.u_bbr.flex4 = thresh;
2450 log.u_bbr.flex5 = to;
2451 log.u_bbr.flex6 = bbr->rc_tp->t_srtt;
2452 log.u_bbr.flex8 = mode;
2453 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2454 &bbr->rc_inp->inp_socket->so_rcv,
2455 &bbr->rc_inp->inp_socket->so_snd,
2456 BBR_LOG_TIMERPREP, 0,
2457 0, &log, false, &bbr->rc_tv);
2458 }
2459 }
2460
2461 static void
2462 bbr_log_pacing_delay_calc(struct tcp_bbr *bbr, uint16_t gain, uint32_t len,
2463 uint32_t cts, uint32_t usecs, uint64_t bw, uint32_t override, int mod)
2464 {
2465 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2466 union tcp_log_stackspecific log;
2467
2468 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2469 log.u_bbr.flex1 = usecs;
2470 log.u_bbr.flex2 = len;
2471 log.u_bbr.flex3 = (uint32_t)((bw >> 32) & 0x00000000ffffffff);
2472 log.u_bbr.flex4 = (uint32_t)(bw & 0x00000000ffffffff);
2473 if (override)
2474 log.u_bbr.flex5 = (1 << 2);
2475 else
2476 log.u_bbr.flex5 = 0;
2477 log.u_bbr.flex6 = override;
2478 log.u_bbr.flex7 = gain;
2479 log.u_bbr.flex8 = mod;
2480 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2481 &bbr->rc_inp->inp_socket->so_rcv,
2482 &bbr->rc_inp->inp_socket->so_snd,
2483 BBR_LOG_HPTSI_CALC, 0,
2484 len, &log, false, &bbr->rc_tv);
2485 }
2486 }
2487
2488 static void
2489 bbr_log_to_start(struct tcp_bbr *bbr, uint32_t cts, uint32_t to, int32_t slot, uint8_t which)
2490 {
2491 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2492 union tcp_log_stackspecific log;
2493
2494 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2495
2496 log.u_bbr.flex1 = bbr->bbr_timer_src;
2497 log.u_bbr.flex2 = to;
2498 log.u_bbr.flex3 = bbr->r_ctl.rc_hpts_flags;
2499 log.u_bbr.flex4 = slot;
2500 log.u_bbr.flex5 = bbr->rc_inp->inp_hptsslot;
2501 log.u_bbr.flex6 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur);
2502 log.u_bbr.pkts_out = bbr->rc_inp->inp_flags2;
2503 log.u_bbr.flex8 = which;
2504 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2505 &bbr->rc_inp->inp_socket->so_rcv,
2506 &bbr->rc_inp->inp_socket->so_snd,
2507 BBR_LOG_TIMERSTAR, 0,
2508 0, &log, false, &bbr->rc_tv);
2509 }
2510 }
2511
2512 static void
2513 bbr_log_thresh_choice(struct tcp_bbr *bbr, uint32_t cts, uint32_t thresh, uint32_t lro, uint32_t srtt, struct bbr_sendmap *rsm, uint8_t frm)
2514 {
2515 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2516 union tcp_log_stackspecific log;
2517
2518 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2519 log.u_bbr.flex1 = thresh;
2520 log.u_bbr.flex2 = lro;
2521 log.u_bbr.flex3 = bbr->r_ctl.rc_reorder_ts;
2522 log.u_bbr.flex4 = rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)];
2523 log.u_bbr.flex5 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur);
2524 log.u_bbr.flex6 = srtt;
2525 log.u_bbr.flex7 = bbr->r_ctl.rc_reorder_shift;
2526 log.u_bbr.flex8 = frm;
2527 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2528 &bbr->rc_inp->inp_socket->so_rcv,
2529 &bbr->rc_inp->inp_socket->so_snd,
2530 BBR_LOG_THRESH_CALC, 0,
2531 0, &log, false, &bbr->rc_tv);
2532 }
2533 }
2534
2535 static void
2536 bbr_log_to_cancel(struct tcp_bbr *bbr, int32_t line, uint32_t cts, uint8_t hpts_removed)
2537 {
2538 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2539 union tcp_log_stackspecific log;
2540
2541 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2542 log.u_bbr.flex1 = line;
2543 log.u_bbr.flex2 = bbr->bbr_timer_src;
2544 log.u_bbr.flex3 = bbr->r_ctl.rc_hpts_flags;
2545 log.u_bbr.flex4 = bbr->rc_in_persist;
2546 log.u_bbr.flex5 = bbr->r_ctl.rc_target_at_state;
2547 log.u_bbr.flex6 = TICKS_2_USEC(bbr->rc_tp->t_rxtcur);
2548 log.u_bbr.flex8 = hpts_removed;
2549 log.u_bbr.pkts_out = bbr->rc_pacer_started;
2550 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2551 &bbr->rc_inp->inp_socket->so_rcv,
2552 &bbr->rc_inp->inp_socket->so_snd,
2553 BBR_LOG_TIMERCANC, 0,
2554 0, &log, false, &bbr->rc_tv);
2555 }
2556 }
2557
2558 static void
2559 bbr_log_tstmp_validation(struct tcp_bbr *bbr, uint64_t peer_delta, uint64_t delta)
2560 {
2561 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2562 union tcp_log_stackspecific log;
2563
2564 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
2565 log.u_bbr.flex1 = bbr->r_ctl.bbr_peer_tsratio;
2566 log.u_bbr.flex2 = (peer_delta >> 32);
2567 log.u_bbr.flex3 = (peer_delta & 0x00000000ffffffff);
2568 log.u_bbr.flex4 = (delta >> 32);
2569 log.u_bbr.flex5 = (delta & 0x00000000ffffffff);
2570 log.u_bbr.flex7 = bbr->rc_ts_clock_set;
2571 log.u_bbr.flex8 = bbr->rc_ts_cant_be_used;
2572 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2573 &bbr->rc_inp->inp_socket->so_rcv,
2574 &bbr->rc_inp->inp_socket->so_snd,
2575 BBR_LOG_TSTMP_VAL, 0,
2576 0, &log, false, &bbr->rc_tv);
2577 }
2578 }
2579
2580 static void
2581 bbr_log_type_tsosize(struct tcp_bbr *bbr, uint32_t cts, uint32_t tsosz, uint32_t tls, uint32_t old_val, uint32_t maxseg, int hdwr)
2582 {
2583 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2584 union tcp_log_stackspecific log;
2585
2586 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2587 log.u_bbr.flex1 = tsosz;
2588 log.u_bbr.flex2 = tls;
2589 log.u_bbr.flex3 = tcp_min_hptsi_time;
2590 log.u_bbr.flex4 = bbr->r_ctl.bbr_hptsi_bytes_min;
2591 log.u_bbr.flex5 = old_val;
2592 log.u_bbr.flex6 = maxseg;
2593 log.u_bbr.flex7 = bbr->rc_no_pacing;
2594 log.u_bbr.flex7 <<= 1;
2595 log.u_bbr.flex7 |= bbr->rc_past_init_win;
2596 if (hdwr)
2597 log.u_bbr.flex8 = 0x80 | bbr->rc_use_google;
2598 else
2599 log.u_bbr.flex8 = bbr->rc_use_google;
2600 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2601 &bbr->rc_inp->inp_socket->so_rcv,
2602 &bbr->rc_inp->inp_socket->so_snd,
2603 BBR_LOG_BBRTSO, 0,
2604 0, &log, false, &bbr->rc_tv);
2605 }
2606 }
2607
2608 static void
2609 bbr_log_type_rsmclear(struct tcp_bbr *bbr, uint32_t cts, struct bbr_sendmap *rsm,
2610 uint32_t flags, uint32_t line)
2611 {
2612 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2613 union tcp_log_stackspecific log;
2614
2615 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2616 log.u_bbr.flex1 = line;
2617 log.u_bbr.flex2 = rsm->r_start;
2618 log.u_bbr.flex3 = rsm->r_end;
2619 log.u_bbr.flex4 = rsm->r_delivered;
2620 log.u_bbr.flex5 = rsm->r_rtr_cnt;
2621 log.u_bbr.flex6 = rsm->r_dupack;
2622 log.u_bbr.flex7 = rsm->r_tim_lastsent[0];
2623 log.u_bbr.flex8 = rsm->r_flags;
2624 /* Hijack the pkts_out fids */
2625 log.u_bbr.applimited = flags;
2626 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2627 &bbr->rc_inp->inp_socket->so_rcv,
2628 &bbr->rc_inp->inp_socket->so_snd,
2629 BBR_RSM_CLEARED, 0,
2630 0, &log, false, &bbr->rc_tv);
2631 }
2632 }
2633
2634 static void
2635 bbr_log_type_bbrupd(struct tcp_bbr *bbr, uint8_t flex8, uint32_t cts,
2636 uint32_t flex3, uint32_t flex2, uint32_t flex5,
2637 uint32_t flex6, uint32_t pkts_out, int flex7,
2638 uint32_t flex4, uint32_t flex1)
2639 {
2640
2641 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2642 union tcp_log_stackspecific log;
2643
2644 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2645 log.u_bbr.flex1 = flex1;
2646 log.u_bbr.flex2 = flex2;
2647 log.u_bbr.flex3 = flex3;
2648 log.u_bbr.flex4 = flex4;
2649 log.u_bbr.flex5 = flex5;
2650 log.u_bbr.flex6 = flex6;
2651 log.u_bbr.flex7 = flex7;
2652 /* Hijack the pkts_out fids */
2653 log.u_bbr.pkts_out = pkts_out;
2654 log.u_bbr.flex8 = flex8;
2655 if (bbr->rc_ack_was_delayed)
2656 log.u_bbr.epoch = bbr->r_ctl.rc_ack_hdwr_delay;
2657 else
2658 log.u_bbr.epoch = 0;
2659 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2660 &bbr->rc_inp->inp_socket->so_rcv,
2661 &bbr->rc_inp->inp_socket->so_snd,
2662 BBR_LOG_BBRUPD, 0,
2663 flex2, &log, false, &bbr->rc_tv);
2664 }
2665 }
2666
2667 static void
2668 bbr_log_type_ltbw(struct tcp_bbr *bbr, uint32_t cts, int32_t reason,
2669 uint32_t newbw, uint32_t obw, uint32_t diff,
2670 uint32_t tim)
2671 {
2672 if (/*bbr_verbose_logging && */(bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2673 union tcp_log_stackspecific log;
2674
2675 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2676 log.u_bbr.flex1 = reason;
2677 log.u_bbr.flex2 = newbw;
2678 log.u_bbr.flex3 = obw;
2679 log.u_bbr.flex4 = diff;
2680 log.u_bbr.flex5 = bbr->r_ctl.rc_lt_lost;
2681 log.u_bbr.flex6 = bbr->r_ctl.rc_lt_del;
2682 log.u_bbr.flex7 = bbr->rc_lt_is_sampling;
2683 log.u_bbr.pkts_out = tim;
2684 log.u_bbr.bw_inuse = bbr->r_ctl.rc_lt_bw;
2685 if (bbr->rc_lt_use_bw == 0)
2686 log.u_bbr.epoch = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch;
2687 else
2688 log.u_bbr.epoch = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch_use;
2689 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2690 &bbr->rc_inp->inp_socket->so_rcv,
2691 &bbr->rc_inp->inp_socket->so_snd,
2692 BBR_LOG_BWSAMP, 0,
2693 0, &log, false, &bbr->rc_tv);
2694 }
2695 }
2696
2697 static inline void
2698 bbr_log_progress_event(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t tick, int event, int line)
2699 {
2700 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2701 union tcp_log_stackspecific log;
2702
2703 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
2704 log.u_bbr.flex1 = line;
2705 log.u_bbr.flex2 = tick;
2706 log.u_bbr.flex3 = tp->t_maxunacktime;
2707 log.u_bbr.flex4 = tp->t_acktime;
2708 log.u_bbr.flex8 = event;
2709 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2710 &bbr->rc_inp->inp_socket->so_rcv,
2711 &bbr->rc_inp->inp_socket->so_snd,
2712 BBR_LOG_PROGRESS, 0,
2713 0, &log, false, &bbr->rc_tv);
2714 }
2715 }
2716
2717 static void
2718 bbr_type_log_hdwr_pacing(struct tcp_bbr *bbr, const struct ifnet *ifp,
2719 uint64_t rate, uint64_t hw_rate, int line, uint32_t cts,
2720 int error)
2721 {
2722 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2723 union tcp_log_stackspecific log;
2724
2725 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2726 log.u_bbr.flex1 = ((hw_rate >> 32) & 0x00000000ffffffff);
2727 log.u_bbr.flex2 = (hw_rate & 0x00000000ffffffff);
2728 log.u_bbr.flex3 = (((uint64_t)ifp >> 32) & 0x00000000ffffffff);
2729 log.u_bbr.flex4 = ((uint64_t)ifp & 0x00000000ffffffff);
2730 log.u_bbr.bw_inuse = rate;
2731 log.u_bbr.flex5 = line;
2732 log.u_bbr.flex6 = error;
2733 log.u_bbr.flex8 = bbr->skip_gain;
2734 log.u_bbr.flex8 <<= 1;
2735 log.u_bbr.flex8 |= bbr->gain_is_limited;
2736 log.u_bbr.flex8 <<= 1;
2737 log.u_bbr.flex8 |= bbr->bbr_hdrw_pacing;
2738 log.u_bbr.pkts_out = bbr->rc_tp->t_maxseg;
2739 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2740 &bbr->rc_inp->inp_socket->so_rcv,
2741 &bbr->rc_inp->inp_socket->so_snd,
2742 BBR_LOG_HDWR_PACE, 0,
2743 0, &log, false, &bbr->rc_tv);
2744 }
2745 }
2746
2747 static void
2748 bbr_log_type_bbrsnd(struct tcp_bbr *bbr, uint32_t len, uint32_t slot, uint32_t del_by, uint32_t cts, uint32_t line, uint32_t prev_delay)
2749 {
2750 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2751 union tcp_log_stackspecific log;
2752
2753 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2754 log.u_bbr.flex1 = slot;
2755 log.u_bbr.flex2 = del_by;
2756 log.u_bbr.flex3 = prev_delay;
2757 log.u_bbr.flex4 = line;
2758 log.u_bbr.flex5 = bbr->r_ctl.rc_last_delay_val;
2759 log.u_bbr.flex6 = bbr->r_ctl.rc_hptsi_agg_delay;
2760 log.u_bbr.flex7 = (0x0000ffff & bbr->r_ctl.rc_hpts_flags);
2761 log.u_bbr.flex8 = bbr->rc_in_persist;
2762 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2763 &bbr->rc_inp->inp_socket->so_rcv,
2764 &bbr->rc_inp->inp_socket->so_snd,
2765 BBR_LOG_BBRSND, 0,
2766 len, &log, false, &bbr->rc_tv);
2767 }
2768 }
2769
2770 static void
2771 bbr_log_type_bbrrttprop(struct tcp_bbr *bbr, uint32_t t, uint32_t end, uint32_t tsconv, uint32_t cts, int32_t match, uint32_t seq, uint8_t flags)
2772 {
2773 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2774 union tcp_log_stackspecific log;
2775
2776 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2777 log.u_bbr.flex1 = bbr->r_ctl.rc_delivered;
2778 log.u_bbr.flex2 = 0;
2779 log.u_bbr.flex3 = bbr->r_ctl.rc_lowest_rtt;
2780 log.u_bbr.flex4 = end;
2781 log.u_bbr.flex5 = seq;
2782 log.u_bbr.flex6 = t;
2783 log.u_bbr.flex7 = match;
2784 log.u_bbr.flex8 = flags;
2785 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2786 &bbr->rc_inp->inp_socket->so_rcv,
2787 &bbr->rc_inp->inp_socket->so_snd,
2788 BBR_LOG_BBRRTT, 0,
2789 0, &log, false, &bbr->rc_tv);
2790 }
2791 }
2792
2793 static void
2794 bbr_log_exit_gain(struct tcp_bbr *bbr, uint32_t cts, int32_t entry_method)
2795 {
2796 if (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF) {
2797 union tcp_log_stackspecific log;
2798
2799 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
2800 log.u_bbr.flex1 = bbr->r_ctl.rc_target_at_state;
2801 log.u_bbr.flex2 = (bbr->rc_tp->t_maxseg - bbr->rc_last_options);
2802 log.u_bbr.flex3 = bbr->r_ctl.gain_epoch;
2803 log.u_bbr.flex4 = bbr->r_ctl.rc_pace_max_segs;
2804 log.u_bbr.flex5 = bbr->r_ctl.rc_pace_min_segs;
2805 log.u_bbr.flex6 = bbr->r_ctl.rc_bbr_state_atflight;
2806 log.u_bbr.flex7 = 0;
2807 log.u_bbr.flex8 = entry_method;
2808 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2809 &bbr->rc_inp->inp_socket->so_rcv,
2810 &bbr->rc_inp->inp_socket->so_snd,
2811 BBR_LOG_EXIT_GAIN, 0,
2812 0, &log, false, &bbr->rc_tv);
2813 }
2814 }
2815
2816 static void
2817 bbr_log_settings_change(struct tcp_bbr *bbr, int settings_desired)
2818 {
2819 if (bbr_verbose_logging && (bbr->rc_tp->t_logstate != TCP_LOG_STATE_OFF)) {
2820 union tcp_log_stackspecific log;
2821
2822 bbr_fill_in_logging_data(bbr, &log.u_bbr, bbr->r_ctl.rc_rcvtime);
2823 /* R-HU */
2824 log.u_bbr.flex1 = 0;
2825 log.u_bbr.flex2 = 0;
2826 log.u_bbr.flex3 = 0;
2827 log.u_bbr.flex4 = 0;
2828 log.u_bbr.flex7 = 0;
2829 log.u_bbr.flex8 = settings_desired;
2830
2831 TCP_LOG_EVENTP(bbr->rc_tp, NULL,
2832 &bbr->rc_inp->inp_socket->so_rcv,
2833 &bbr->rc_inp->inp_socket->so_snd,
2834 BBR_LOG_SETTINGS_CHG, 0,
2835 0, &log, false, &bbr->rc_tv);
2836 }
2837 }
2838
2839 /*
2840 * Returns the bw from the our filter.
2841 */
2842 static inline uint64_t
2843 bbr_get_full_bw(struct tcp_bbr *bbr)
2844 {
2845 uint64_t bw;
2846
2847 bw = get_filter_value(&bbr->r_ctl.rc_delrate);
2848
2849 return (bw);
2850 }
2851
2852 static inline void
2853 bbr_set_pktepoch(struct tcp_bbr *bbr, uint32_t cts, int32_t line)
2854 {
2855 uint64_t calclr;
2856 uint32_t lost, del;
2857
2858 if (bbr->r_ctl.rc_lost > bbr->r_ctl.rc_lost_at_pktepoch)
2859 lost = bbr->r_ctl.rc_lost - bbr->r_ctl.rc_lost_at_pktepoch;
2860 else
2861 lost = 0;
2862 del = bbr->r_ctl.rc_delivered - bbr->r_ctl.rc_pkt_epoch_del;
2863 if (lost == 0) {
2864 calclr = 0;
2865 } else if (del) {
2866 calclr = lost;
2867 calclr *= (uint64_t)1000;
2868 calclr /= (uint64_t)del;
2869 } else {
2870 /* Nothing delivered? 100.0% loss */
2871 calclr = 1000;
2872 }
2873 bbr->r_ctl.rc_pkt_epoch_loss_rate = (uint32_t)calclr;
2874 if (IN_RECOVERY(bbr->rc_tp->t_flags))
2875 bbr->r_ctl.recovery_lr += (uint32_t)calclr;
2876 bbr->r_ctl.rc_pkt_epoch++;
2877 if (bbr->rc_no_pacing &&
2878 (bbr->r_ctl.rc_pkt_epoch >= bbr->no_pacing_until)) {
2879 bbr->rc_no_pacing = 0;
2880 tcp_bbr_tso_size_check(bbr, cts);
2881 }
2882 bbr->r_ctl.rc_pkt_epoch_rtt = bbr_calc_time(cts, bbr->r_ctl.rc_pkt_epoch_time);
2883 bbr->r_ctl.rc_pkt_epoch_time = cts;
2884 /* What was our loss rate */
2885 bbr_log_pkt_epoch(bbr, cts, line, lost, del);
2886 bbr->r_ctl.rc_pkt_epoch_del = bbr->r_ctl.rc_delivered;
2887 bbr->r_ctl.rc_lost_at_pktepoch = bbr->r_ctl.rc_lost;
2888 }
2889
2890 static inline void
2891 bbr_set_epoch(struct tcp_bbr *bbr, uint32_t cts, int32_t line)
2892 {
2893 uint32_t epoch_time;
2894
2895 /* Tick the RTT clock */
2896 bbr->r_ctl.rc_rtt_epoch++;
2897 epoch_time = cts - bbr->r_ctl.rc_rcv_epoch_start;
2898 bbr_log_time_epoch(bbr, cts, line, epoch_time);
2899 bbr->r_ctl.rc_rcv_epoch_start = cts;
2900 }
2901
2902 static inline void
2903 bbr_isit_a_pkt_epoch(struct tcp_bbr *bbr, uint32_t cts, struct bbr_sendmap *rsm, int32_t line, int32_t cum_acked)
2904 {
2905 if (SEQ_GEQ(rsm->r_delivered, bbr->r_ctl.rc_pkt_epoch_del)) {
2906 bbr->rc_is_pkt_epoch_now = 1;
2907 }
2908 }
2909
2910 /*
2911 * Returns the bw from either the b/w filter
2912 * or from the lt_bw (if the connection is being
2913 * policed).
2914 */
2915 static inline uint64_t
2916 __bbr_get_bw(struct tcp_bbr *bbr)
2917 {
2918 uint64_t bw, min_bw;
2919 uint64_t rtt;
2920 int gm_measure_cnt = 1;
2921
2922 /*
2923 * For startup we make, like google, a
2924 * minimum b/w. This is generated from the
2925 * IW and the rttProp. We do fall back to srtt
2926 * if for some reason (initial handshake) we don't
2927 * have a rttProp. We, in the worst case, fall back
2928 * to the configured min_bw (rc_initial_hptsi_bw).
2929 */
2930 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) {
2931 /* Attempt first to use rttProp */
2932 rtt = (uint64_t)get_filter_value_small(&bbr->r_ctl.rc_rttprop);
2933 if (rtt && (rtt < 0xffffffff)) {
2934 measure:
2935 min_bw = (uint64_t)(bbr_initial_cwnd(bbr, bbr->rc_tp)) *
2936 ((uint64_t)1000000);
2937 min_bw /= rtt;
2938 if (min_bw < bbr->r_ctl.rc_initial_hptsi_bw) {
2939 min_bw = bbr->r_ctl.rc_initial_hptsi_bw;
2940 }
2941
2942 } else if (bbr->rc_tp->t_srtt != 0) {
2943 /* No rttProp, use srtt? */
2944 rtt = bbr_get_rtt(bbr, BBR_SRTT);
2945 goto measure;
2946 } else {
2947 min_bw = bbr->r_ctl.rc_initial_hptsi_bw;
2948 }
2949 } else
2950 min_bw = 0;
2951
2952 if ((bbr->rc_past_init_win == 0) &&
2953 (bbr->r_ctl.rc_delivered > bbr_initial_cwnd(bbr, bbr->rc_tp)))
2954 bbr->rc_past_init_win = 1;
2955 if ((bbr->rc_use_google) && (bbr->r_ctl.r_measurement_count >= 1))
2956 gm_measure_cnt = 0;
2957 if (gm_measure_cnt &&
2958 ((bbr->r_ctl.r_measurement_count < bbr_min_measurements_req) ||
2959 (bbr->rc_past_init_win == 0))) {
2960 /* For google we use our guess rate until we get 1 measurement */
2961
2962 use_initial_window:
2963 rtt = (uint64_t)get_filter_value_small(&bbr->r_ctl.rc_rttprop);
2964 if (rtt && (rtt < 0xffffffff)) {
2965 /*
2966 * We have an RTT measurement. Use that in
2967 * combination with our initial window to calculate
2968 * a b/w.
2969 */
2970 bw = (uint64_t)(bbr_initial_cwnd(bbr, bbr->rc_tp)) *
2971 ((uint64_t)1000000);
2972 bw /= rtt;
2973 if (bw < bbr->r_ctl.rc_initial_hptsi_bw) {
2974 bw = bbr->r_ctl.rc_initial_hptsi_bw;
2975 }
2976 } else {
2977 /* Drop back to the 40 and punt to a default */
2978 bw = bbr->r_ctl.rc_initial_hptsi_bw;
2979 }
2980 if (bw < 1)
2981 /* Probably should panic */
2982 bw = 1;
2983 if (bw > min_bw)
2984 return (bw);
2985 else
2986 return (min_bw);
2987 }
2988 if (bbr->rc_lt_use_bw)
2989 bw = bbr->r_ctl.rc_lt_bw;
2990 else if (bbr->r_recovery_bw && (bbr->rc_use_google == 0))
2991 bw = bbr->r_ctl.red_bw;
2992 else
2993 bw = get_filter_value(&bbr->r_ctl.rc_delrate);
2994 if (bbr->rc_tp->t_peakrate_thr && (bbr->rc_use_google == 0)) {
2995 /*
2996 * Enforce user set rate limit, keep in mind that
2997 * t_peakrate_thr is in B/s already
2998 */
2999 bw = uqmin((uint64_t)bbr->rc_tp->t_peakrate_thr, bw);
3000 }
3001 if (bw == 0) {
3002 /* We should not be at 0, go to the initial window then */
3003 goto use_initial_window;
3004 }
3005 if (bw < 1)
3006 /* Probably should panic */
3007 bw = 1;
3008 if (bw < min_bw)
3009 bw = min_bw;
3010 return (bw);
3011 }
3012
3013 static inline uint64_t
3014 bbr_get_bw(struct tcp_bbr *bbr)
3015 {
3016 uint64_t bw;
3017
3018 bw = __bbr_get_bw(bbr);
3019 return (bw);
3020 }
3021
3022 static inline void
3023 bbr_reset_lt_bw_interval(struct tcp_bbr *bbr, uint32_t cts)
3024 {
3025 bbr->r_ctl.rc_lt_epoch = bbr->r_ctl.rc_pkt_epoch;
3026 bbr->r_ctl.rc_lt_time = bbr->r_ctl.rc_del_time;
3027 bbr->r_ctl.rc_lt_del = bbr->r_ctl.rc_delivered;
3028 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost;
3029 }
3030
3031 static inline void
3032 bbr_reset_lt_bw_sampling(struct tcp_bbr *bbr, uint32_t cts)
3033 {
3034 bbr->rc_lt_is_sampling = 0;
3035 bbr->rc_lt_use_bw = 0;
3036 bbr->r_ctl.rc_lt_bw = 0;
3037 bbr_reset_lt_bw_interval(bbr, cts);
3038 }
3039
3040 static inline void
3041 bbr_lt_bw_samp_done(struct tcp_bbr *bbr, uint64_t bw, uint32_t cts, uint32_t timin)
3042 {
3043 uint64_t diff;
3044
3045 /* Do we have a previous sample? */
3046 if (bbr->r_ctl.rc_lt_bw) {
3047 /* Get the diff in bytes per second */
3048 if (bbr->r_ctl.rc_lt_bw > bw)
3049 diff = bbr->r_ctl.rc_lt_bw - bw;
3050 else
3051 diff = bw - bbr->r_ctl.rc_lt_bw;
3052 if ((diff <= bbr_lt_bw_diff) ||
3053 (diff <= (bbr->r_ctl.rc_lt_bw / bbr_lt_bw_ratio))) {
3054 /* Consider us policed */
3055 uint32_t saved_bw;
3056
3057 saved_bw = (uint32_t)bbr->r_ctl.rc_lt_bw;
3058 bbr->r_ctl.rc_lt_bw = (bw + bbr->r_ctl.rc_lt_bw) / 2; /* average of two */
3059 bbr->rc_lt_use_bw = 1;
3060 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT;
3061 /*
3062 * Use pkt based epoch for measuring length of
3063 * policer up
3064 */
3065 bbr->r_ctl.rc_lt_epoch_use = bbr->r_ctl.rc_pkt_epoch;
3066 /*
3067 * reason 4 is we need to start consider being
3068 * policed
3069 */
3070 bbr_log_type_ltbw(bbr, cts, 4, (uint32_t)bw, saved_bw, (uint32_t)diff, timin);
3071 return;
3072 }
3073 }
3074 bbr->r_ctl.rc_lt_bw = bw;
3075 bbr_reset_lt_bw_interval(bbr, cts);
3076 bbr_log_type_ltbw(bbr, cts, 5, 0, (uint32_t)bw, 0, timin);
3077 }
3078
3079 static void
3080 bbr_randomize_extra_state_time(struct tcp_bbr *bbr)
3081 {
3082 uint32_t ran, deduct;
3083
3084 ran = arc4random_uniform(bbr_rand_ot);
3085 if (ran) {
3086 deduct = bbr->r_ctl.rc_level_state_extra / ran;
3087 bbr->r_ctl.rc_level_state_extra -= deduct;
3088 }
3089 }
3090 /*
3091 * Return randomly the starting state
3092 * to use in probebw.
3093 */
3094 static uint8_t
3095 bbr_pick_probebw_substate(struct tcp_bbr *bbr, uint32_t cts)
3096 {
3097 uint32_t ran;
3098 uint8_t ret_val;
3099
3100 /* Initialize the offset to 0 */
3101 bbr->r_ctl.rc_exta_time_gd = 0;
3102 bbr->rc_hit_state_1 = 0;
3103 bbr->r_ctl.rc_level_state_extra = 0;
3104 ran = arc4random_uniform((BBR_SUBSTATE_COUNT-1));
3105 /*
3106 * The math works funny here :) the return value is used to set the
3107 * substate and then the state change is called which increments by
3108 * one. So if we return 1 (DRAIN) we will increment to 2 (LEVEL1) when
3109 * we fully enter the state. Note that the (8 - 1 - ran) assures that
3110 * we return 1 - 7, so we dont return 0 and end up starting in
3111 * state 1 (DRAIN).
3112 */
3113 ret_val = BBR_SUBSTATE_COUNT - 1 - ran;
3114 /* Set an epoch */
3115 if ((cts - bbr->r_ctl.rc_rcv_epoch_start) >= bbr_get_rtt(bbr, BBR_RTT_PROP))
3116 bbr_set_epoch(bbr, cts, __LINE__);
3117
3118 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost;
3119 return (ret_val);
3120 }
3121
3122 static void
3123 bbr_lt_bw_sampling(struct tcp_bbr *bbr, uint32_t cts, int32_t loss_detected)
3124 {
3125 uint32_t diff, d_time;
3126 uint64_t del_time, bw, lost, delivered;
3127
3128 if (bbr->r_use_policer == 0)
3129 return;
3130 if (bbr->rc_lt_use_bw) {
3131 /* We are using lt bw do we stop yet? */
3132 diff = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch_use;
3133 if (diff > bbr_lt_bw_max_rtts) {
3134 /* Reset it all */
3135 reset_all:
3136 bbr_reset_lt_bw_sampling(bbr, cts);
3137 if (bbr->rc_filled_pipe) {
3138 bbr_set_epoch(bbr, cts, __LINE__);
3139 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts);
3140 bbr_substate_change(bbr, cts, __LINE__, 0);
3141 bbr->rc_bbr_state = BBR_STATE_PROBE_BW;
3142 bbr_log_type_statechange(bbr, cts, __LINE__);
3143 } else {
3144 /*
3145 * This should not happen really
3146 * unless we remove the startup/drain
3147 * restrictions above.
3148 */
3149 bbr->rc_bbr_state = BBR_STATE_STARTUP;
3150 bbr_set_epoch(bbr, cts, __LINE__);
3151 bbr->r_ctl.rc_bbr_state_time = cts;
3152 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost;
3153 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_startup_pg;
3154 bbr->r_ctl.rc_bbr_cwnd_gain = bbr->r_ctl.rc_startup_pg;
3155 bbr_set_state_target(bbr, __LINE__);
3156 bbr_log_type_statechange(bbr, cts, __LINE__);
3157 }
3158 /* reason 0 is to stop using lt-bw */
3159 bbr_log_type_ltbw(bbr, cts, 0, 0, 0, 0, 0);
3160 return;
3161 }
3162 if (bbr_lt_intvl_fp == 0) {
3163 /* Not doing false-positive detection */
3164 return;
3165 }
3166 /* False positive detection */
3167 if (diff == bbr_lt_intvl_fp) {
3168 /* At bbr_lt_intvl_fp we record the lost */
3169 bbr->r_ctl.rc_lt_del = bbr->r_ctl.rc_delivered;
3170 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost;
3171 } else if (diff > (bbr_lt_intvl_min_rtts + bbr_lt_intvl_fp)) {
3172 /* Now is our loss rate still high? */
3173 lost = bbr->r_ctl.rc_lost - bbr->r_ctl.rc_lt_lost;
3174 delivered = bbr->r_ctl.rc_delivered - bbr->r_ctl.rc_lt_del;
3175 if ((delivered == 0) ||
3176 (((lost * 1000)/delivered) < bbr_lt_fd_thresh)) {
3177 /* No still below our threshold */
3178 bbr_log_type_ltbw(bbr, cts, 7, lost, delivered, 0, 0);
3179 } else {
3180 /* Yikes its still high, it must be a false positive */
3181 bbr_log_type_ltbw(bbr, cts, 8, lost, delivered, 0, 0);
3182 goto reset_all;
3183 }
3184 }
3185 return;
3186 }
3187 /*
3188 * Wait for the first loss before sampling, to let the policer
3189 * exhaust its tokens and estimate the steady-state rate allowed by
3190 * the policer. Starting samples earlier includes bursts that
3191 * over-estimate the bw.
3192 */
3193 if (bbr->rc_lt_is_sampling == 0) {
3194 /* reason 1 is to begin doing the sampling */
3195 if (loss_detected == 0)
3196 return;
3197 bbr_reset_lt_bw_interval(bbr, cts);
3198 bbr->rc_lt_is_sampling = 1;
3199 bbr_log_type_ltbw(bbr, cts, 1, 0, 0, 0, 0);
3200 return;
3201 }
3202 /* Now how long were we delivering long term last> */
3203 if (TSTMP_GEQ(bbr->r_ctl.rc_del_time, bbr->r_ctl.rc_lt_time))
3204 d_time = bbr->r_ctl.rc_del_time - bbr->r_ctl.rc_lt_time;
3205 else
3206 d_time = 0;
3207
3208 /* To avoid underestimates, reset sampling if we run out of data. */
3209 if (bbr->r_ctl.r_app_limited_until) {
3210 /* Can not measure in app-limited state */
3211 bbr_reset_lt_bw_sampling(bbr, cts);
3212 /* reason 2 is to reset sampling due to app limits */
3213 bbr_log_type_ltbw(bbr, cts, 2, 0, 0, 0, d_time);
3214 return;
3215 }
3216 diff = bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_lt_epoch;
3217 if (diff < bbr_lt_intvl_min_rtts) {
3218 /*
3219 * need more samples (we don't
3220 * start on a round like linux so
3221 * we need 1 more).
3222 */
3223 /* 6 is not_enough time or no-loss */
3224 bbr_log_type_ltbw(bbr, cts, 6, 0, 0, 0, d_time);
3225 return;
3226 }
3227 if (diff > (4 * bbr_lt_intvl_min_rtts)) {
3228 /*
3229 * For now if we wait too long, reset all sampling. We need
3230 * to do some research here, its possible that we should
3231 * base this on how much loss as occurred.. something like
3232 * if its under 10% (or some thresh) reset all otherwise
3233 * don't. Thats for phase II I guess.
3234 */
3235 bbr_reset_lt_bw_sampling(bbr, cts);
3236 /* reason 3 is to reset sampling due too long of sampling */
3237 bbr_log_type_ltbw(bbr, cts, 3, 0, 0, 0, d_time);
3238 return;
3239 }
3240 /*
3241 * End sampling interval when a packet is lost, so we estimate the
3242 * policer tokens were exhausted. Stopping the sampling before the
3243 * tokens are exhausted under-estimates the policed rate.
3244 */
3245 if (loss_detected == 0) {
3246 /* 6 is not_enough time or no-loss */
3247 bbr_log_type_ltbw(bbr, cts, 6, 0, 0, 0, d_time);
3248 return;
3249 }
3250 /* Calculate packets lost and delivered in sampling interval. */
3251 lost = bbr->r_ctl.rc_lost - bbr->r_ctl.rc_lt_lost;
3252 delivered = bbr->r_ctl.rc_delivered - bbr->r_ctl.rc_lt_del;
3253 if ((delivered == 0) ||
3254 (((lost * 1000)/delivered) < bbr_lt_loss_thresh)) {
3255 bbr_log_type_ltbw(bbr, cts, 6, lost, delivered, 0, d_time);
3256 return;
3257 }
3258 if (d_time < 1000) {
3259 /* Not enough time. wait */
3260 /* 6 is not_enough time or no-loss */
3261 bbr_log_type_ltbw(bbr, cts, 6, 0, 0, 0, d_time);
3262 return;
3263 }
3264 if (d_time >= (0xffffffff / USECS_IN_MSEC)) {
3265 /* Too long */
3266 bbr_reset_lt_bw_sampling(bbr, cts);
3267 /* reason 3 is to reset sampling due too long of sampling */
3268 bbr_log_type_ltbw(bbr, cts, 3, 0, 0, 0, d_time);
3269 return;
3270 }
3271 del_time = d_time;
3272 bw = delivered;
3273 bw *= (uint64_t)USECS_IN_SECOND;
3274 bw /= del_time;
3275 bbr_lt_bw_samp_done(bbr, bw, cts, d_time);
3276 }
3277
3278 /*
3279 * Allocate a sendmap from our zone.
3280 */
3281 static struct bbr_sendmap *
3282 bbr_alloc(struct tcp_bbr *bbr)
3283 {
3284 struct bbr_sendmap *rsm;
3285
3286 BBR_STAT_INC(bbr_to_alloc);
3287 rsm = uma_zalloc(bbr_zone, (M_NOWAIT | M_ZERO));
3288 if (rsm) {
3289 bbr->r_ctl.rc_num_maps_alloced++;
3290 return (rsm);
3291 }
3292 if (bbr->r_ctl.rc_free_cnt) {
3293 BBR_STAT_INC(bbr_to_alloc_emerg);
3294 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_free);
3295 TAILQ_REMOVE(&bbr->r_ctl.rc_free, rsm, r_next);
3296 bbr->r_ctl.rc_free_cnt--;
3297 return (rsm);
3298 }
3299 BBR_STAT_INC(bbr_to_alloc_failed);
3300 return (NULL);
3301 }
3302
3303 static struct bbr_sendmap *
3304 bbr_alloc_full_limit(struct tcp_bbr *bbr)
3305 {
3306 if ((V_tcp_map_entries_limit > 0) &&
3307 (bbr->r_ctl.rc_num_maps_alloced >= V_tcp_map_entries_limit)) {
3308 BBR_STAT_INC(bbr_alloc_limited);
3309 if (!bbr->alloc_limit_reported) {
3310 bbr->alloc_limit_reported = 1;
3311 BBR_STAT_INC(bbr_alloc_limited_conns);
3312 }
3313 return (NULL);
3314 }
3315 return (bbr_alloc(bbr));
3316 }
3317
3318 /* wrapper to allocate a sendmap entry, subject to a specific limit */
3319 static struct bbr_sendmap *
3320 bbr_alloc_limit(struct tcp_bbr *bbr, uint8_t limit_type)
3321 {
3322 struct bbr_sendmap *rsm;
3323
3324 if (limit_type) {
3325 /* currently there is only one limit type */
3326 if (V_tcp_map_split_limit > 0 &&
3327 bbr->r_ctl.rc_num_split_allocs >= V_tcp_map_split_limit) {
3328 BBR_STAT_INC(bbr_split_limited);
3329 if (!bbr->alloc_limit_reported) {
3330 bbr->alloc_limit_reported = 1;
3331 BBR_STAT_INC(bbr_alloc_limited_conns);
3332 }
3333 return (NULL);
3334 }
3335 }
3336
3337 /* allocate and mark in the limit type, if set */
3338 rsm = bbr_alloc(bbr);
3339 if (rsm != NULL && limit_type) {
3340 rsm->r_limit_type = limit_type;
3341 bbr->r_ctl.rc_num_split_allocs++;
3342 }
3343 return (rsm);
3344 }
3345
3346 static void
3347 bbr_free(struct tcp_bbr *bbr, struct bbr_sendmap *rsm)
3348 {
3349 if (rsm->r_limit_type) {
3350 /* currently there is only one limit type */
3351 bbr->r_ctl.rc_num_split_allocs--;
3352 }
3353 if (rsm->r_is_smallmap)
3354 bbr->r_ctl.rc_num_small_maps_alloced--;
3355 if (bbr->r_ctl.rc_tlp_send == rsm)
3356 bbr->r_ctl.rc_tlp_send = NULL;
3357 if (bbr->r_ctl.rc_resend == rsm) {
3358 bbr->r_ctl.rc_resend = NULL;
3359 }
3360 if (bbr->r_ctl.rc_next == rsm)
3361 bbr->r_ctl.rc_next = NULL;
3362 if (bbr->r_ctl.rc_sacklast == rsm)
3363 bbr->r_ctl.rc_sacklast = NULL;
3364 if (bbr->r_ctl.rc_free_cnt < bbr_min_req_free) {
3365 memset(rsm, 0, sizeof(struct bbr_sendmap));
3366 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_free, rsm, r_next);
3367 rsm->r_limit_type = 0;
3368 bbr->r_ctl.rc_free_cnt++;
3369 return;
3370 }
3371 bbr->r_ctl.rc_num_maps_alloced--;
3372 uma_zfree(bbr_zone, rsm);
3373 }
3374
3375 /*
3376 * Returns the BDP.
3377 */
3378 static uint64_t
3379 bbr_get_bw_delay_prod(uint64_t rtt, uint64_t bw) {
3380 /*
3381 * Calculate the bytes in flight needed given the bw (in bytes per
3382 * second) and the specifyed rtt in useconds. We need to put out the
3383 * returned value per RTT to match that rate. Gain will normally
3384 * raise it up from there.
3385 *
3386 * This should not overflow as long as the bandwidth is below 1
3387 * TByte per second (bw < 10**12 = 2**40) and the rtt is smaller
3388 * than 1000 seconds (rtt < 10**3 * 10**6 = 10**9 = 2**30).
3389 */
3390 uint64_t usec_per_sec;
3391
3392 usec_per_sec = USECS_IN_SECOND;
3393 return ((rtt * bw) / usec_per_sec);
3394 }
3395
3396 /*
3397 * Return the initial cwnd.
3398 */
3399 static uint32_t
3400 bbr_initial_cwnd(struct tcp_bbr *bbr, struct tcpcb *tp)
3401 {
3402 uint32_t i_cwnd;
3403
3404 if (bbr->rc_init_win) {
3405 i_cwnd = bbr->rc_init_win * tp->t_maxseg;
3406 } else if (V_tcp_initcwnd_segments)
3407 i_cwnd = min((V_tcp_initcwnd_segments * tp->t_maxseg),
3408 max(2 * tp->t_maxseg, 14600));
3409 else if (V_tcp_do_rfc3390)
3410 i_cwnd = min(4 * tp->t_maxseg,
3411 max(2 * tp->t_maxseg, 4380));
3412 else {
3413 /* Per RFC5681 Section 3.1 */
3414 if (tp->t_maxseg > 2190)
3415 i_cwnd = 2 * tp->t_maxseg;
3416 else if (tp->t_maxseg > 1095)
3417 i_cwnd = 3 * tp->t_maxseg;
3418 else
3419 i_cwnd = 4 * tp->t_maxseg;
3420 }
3421 return (i_cwnd);
3422 }
3423
3424 /*
3425 * Given a specified gain, return the target
3426 * cwnd based on that gain.
3427 */
3428 static uint32_t
3429 bbr_get_raw_target_cwnd(struct tcp_bbr *bbr, uint32_t gain, uint64_t bw)
3430 {
3431 uint64_t bdp, rtt;
3432 uint32_t cwnd;
3433
3434 if ((get_filter_value_small(&bbr->r_ctl.rc_rttprop) == 0xffffffff) ||
3435 (bbr_get_full_bw(bbr) == 0)) {
3436 /* No measurements yet */
3437 return (bbr_initial_cwnd(bbr, bbr->rc_tp));
3438 }
3439 /*
3440 * Get bytes per RTT needed (rttProp is normally in
3441 * bbr_cwndtarget_rtt_touse)
3442 */
3443 rtt = bbr_get_rtt(bbr, bbr_cwndtarget_rtt_touse);
3444 /* Get the bdp from the two values */
3445 bdp = bbr_get_bw_delay_prod(rtt, bw);
3446 /* Now apply the gain */
3447 cwnd = (uint32_t)(((bdp * ((uint64_t)gain)) + (uint64_t)(BBR_UNIT - 1)) / ((uint64_t)BBR_UNIT));
3448
3449 return (cwnd);
3450 }
3451
3452 static uint32_t
3453 bbr_get_target_cwnd(struct tcp_bbr *bbr, uint64_t bw, uint32_t gain)
3454 {
3455 uint32_t cwnd, mss;
3456
3457 mss = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), bbr->r_ctl.rc_pace_max_segs);
3458 /* Get the base cwnd with gain rounded to a mss */
3459 cwnd = roundup(bbr_get_raw_target_cwnd(bbr, bw, gain), mss);
3460 /*
3461 * Add in N (2 default since we do not have a
3462 * fq layer to trap packets in) quanta's per the I-D
3463 * section 4.2.3.2 quanta adjust.
3464 */
3465 cwnd += (bbr_quanta * bbr->r_ctl.rc_pace_max_segs);
3466 if (bbr->rc_use_google) {
3467 if((bbr->rc_bbr_state == BBR_STATE_PROBE_BW) &&
3468 (bbr_state_val(bbr) == BBR_SUB_GAIN)) {
3469 /*
3470 * The linux implementation adds
3471 * an extra 2 x mss in gain cycle which
3472 * is documented no-where except in the code.
3473 * so we add more for Neal undocumented feature
3474 */
3475 cwnd += 2 * mss;
3476 }
3477 if ((cwnd / mss) & 0x1) {
3478 /* Round up for odd num mss */
3479 cwnd += mss;
3480 }
3481 }
3482 /* Are we below the min cwnd? */
3483 if (cwnd < get_min_cwnd(bbr))
3484 return (get_min_cwnd(bbr));
3485 return (cwnd);
3486 }
3487
3488 static uint16_t
3489 bbr_gain_adjust(struct tcp_bbr *bbr, uint16_t gain)
3490 {
3491 if (gain < 1)
3492 gain = 1;
3493 return (gain);
3494 }
3495
3496 static uint32_t
3497 bbr_get_header_oh(struct tcp_bbr *bbr)
3498 {
3499 int seg_oh;
3500
3501 seg_oh = 0;
3502 if (bbr->r_ctl.rc_inc_tcp_oh) {
3503 /* Do we include TCP overhead? */
3504 seg_oh = (bbr->rc_last_options + sizeof(struct tcphdr));
3505 }
3506 if (bbr->r_ctl.rc_inc_ip_oh) {
3507 /* Do we include IP overhead? */
3508 #ifdef INET6
3509 if (bbr->r_is_v6) {
3510 seg_oh += sizeof(struct ip6_hdr);
3511 } else
3512 #endif
3513 {
3514
3515 #ifdef INET
3516 seg_oh += sizeof(struct ip);
3517 #endif
3518 }
3519 }
3520 if (bbr->r_ctl.rc_inc_enet_oh) {
3521 /* Do we include the ethernet overhead? */
3522 seg_oh += sizeof(struct ether_header);
3523 }
3524 return(seg_oh);
3525 }
3526
3527 static uint32_t
3528 bbr_get_pacing_length(struct tcp_bbr *bbr, uint16_t gain, uint32_t useconds_time, uint64_t bw)
3529 {
3530 uint64_t divor, res, tim;
3531
3532 if (useconds_time == 0)
3533 return (0);
3534 gain = bbr_gain_adjust(bbr, gain);
3535 divor = (uint64_t)USECS_IN_SECOND * (uint64_t)BBR_UNIT;
3536 tim = useconds_time;
3537 res = (tim * bw * gain) / divor;
3538 if (res == 0)
3539 res = 1;
3540 return ((uint32_t)res);
3541 }
3542
3543 /*
3544 * Given a gain and a length return the delay in useconds that
3545 * should be used to evenly space out packets
3546 * on the connection (based on the gain factor).
3547 */
3548 static uint32_t
3549 bbr_get_pacing_delay(struct tcp_bbr *bbr, uint16_t gain, int32_t len, uint32_t cts, int nolog)
3550 {
3551 uint64_t bw, lentim, res;
3552 uint32_t usecs, srtt, over = 0;
3553 uint32_t seg_oh, num_segs, maxseg;
3554
3555 if (len == 0)
3556 return (0);
3557
3558 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options;
3559 num_segs = (len + maxseg - 1) / maxseg;
3560 if (bbr->rc_use_google == 0) {
3561 seg_oh = bbr_get_header_oh(bbr);
3562 len += (num_segs * seg_oh);
3563 }
3564 gain = bbr_gain_adjust(bbr, gain);
3565 bw = bbr_get_bw(bbr);
3566 if (bbr->rc_use_google) {
3567 uint64_t cbw;
3568
3569 /*
3570 * Reduce the b/w by the google discount
3571 * factor 10 = 1%.
3572 */
3573 cbw = bw * (uint64_t)(1000 - bbr->r_ctl.bbr_google_discount);
3574 cbw /= (uint64_t)1000;
3575 /* We don't apply a discount if it results in 0 */
3576 if (cbw > 0)
3577 bw = cbw;
3578 }
3579 lentim = ((uint64_t)len *
3580 (uint64_t)USECS_IN_SECOND *
3581 (uint64_t)BBR_UNIT);
3582 res = lentim / ((uint64_t)gain * bw);
3583 if (res == 0)
3584 res = 1;
3585 usecs = (uint32_t)res;
3586 srtt = bbr_get_rtt(bbr, BBR_SRTT);
3587 if (bbr_hptsi_max_mul && bbr_hptsi_max_div &&
3588 (bbr->rc_use_google == 0) &&
3589 (usecs > ((srtt * bbr_hptsi_max_mul) / bbr_hptsi_max_div))) {
3590 /*
3591 * We cannot let the delay be more than 1/2 the srtt time.
3592 * Otherwise we cannot pace out or send properly.
3593 */
3594 over = usecs = (srtt * bbr_hptsi_max_mul) / bbr_hptsi_max_div;
3595 BBR_STAT_INC(bbr_hpts_min_time);
3596 }
3597 if (!nolog)
3598 bbr_log_pacing_delay_calc(bbr, gain, len, cts, usecs, bw, over, 1);
3599 return (usecs);
3600 }
3601
3602 static void
3603 bbr_ack_received(struct tcpcb *tp, struct tcp_bbr *bbr, struct tcphdr *th, uint32_t bytes_this_ack,
3604 uint32_t sack_changed, uint32_t prev_acked, int32_t line, uint32_t losses)
3605 {
3606 uint64_t bw;
3607 uint32_t cwnd, target_cwnd, saved_bytes, maxseg;
3608 int32_t meth;
3609
3610 INP_WLOCK_ASSERT(tptoinpcb(tp));
3611
3612 #ifdef STATS
3613 if ((tp->t_flags & TF_GPUTINPROG) &&
3614 SEQ_GEQ(th->th_ack, tp->gput_ack)) {
3615 /*
3616 * Strech acks and compressed acks will cause this to
3617 * oscillate but we are doing it the same way as the main
3618 * stack so it will be compariable (though possibly not
3619 * ideal).
3620 */
3621 int32_t cgput;
3622 int64_t gput, time_stamp;
3623
3624 gput = (int64_t) (th->th_ack - tp->gput_seq) * 8;
3625 time_stamp = max(1, ((bbr->r_ctl.rc_rcvtime - tp->gput_ts) / 1000));
3626 cgput = gput / time_stamp;
3627 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_GPUT,
3628 cgput);
3629 if (tp->t_stats_gput_prev > 0)
3630 stats_voi_update_abs_s32(tp->t_stats,
3631 VOI_TCP_GPUT_ND,
3632 ((gput - tp->t_stats_gput_prev) * 100) /
3633 tp->t_stats_gput_prev);
3634 tp->t_flags &= ~TF_GPUTINPROG;
3635 tp->t_stats_gput_prev = cgput;
3636 }
3637 #endif
3638 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) &&
3639 ((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google)) {
3640 /* We don't change anything in probe-rtt */
3641 return;
3642 }
3643 maxseg = tp->t_maxseg - bbr->rc_last_options;
3644 saved_bytes = bytes_this_ack;
3645 bytes_this_ack += sack_changed;
3646 if (bytes_this_ack > prev_acked) {
3647 bytes_this_ack -= prev_acked;
3648 /*
3649 * A byte ack'd gives us a full mss
3650 * to be like linux i.e. they count packets.
3651 */
3652 if ((bytes_this_ack < maxseg) && bbr->rc_use_google)
3653 bytes_this_ack = maxseg;
3654 } else {
3655 /* Unlikely */
3656 bytes_this_ack = 0;
3657 }
3658 cwnd = tp->snd_cwnd;
3659 bw = get_filter_value(&bbr->r_ctl.rc_delrate);
3660 if (bw)
3661 target_cwnd = bbr_get_target_cwnd(bbr,
3662 bw,
3663 (uint32_t)bbr->r_ctl.rc_bbr_cwnd_gain);
3664 else
3665 target_cwnd = bbr_initial_cwnd(bbr, bbr->rc_tp);
3666 if (IN_RECOVERY(tp->t_flags) &&
3667 (bbr->bbr_prev_in_rec == 0)) {
3668 /*
3669 * We are entering recovery and
3670 * thus packet conservation.
3671 */
3672 bbr->pkt_conservation = 1;
3673 bbr->r_ctl.rc_recovery_start = bbr->r_ctl.rc_rcvtime;
3674 cwnd = ctf_flight_size(tp,
3675 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) +
3676 bytes_this_ack;
3677 }
3678 if (IN_RECOVERY(tp->t_flags)) {
3679 uint32_t flight;
3680
3681 bbr->bbr_prev_in_rec = 1;
3682 if (cwnd > losses) {
3683 cwnd -= losses;
3684 if (cwnd < maxseg)
3685 cwnd = maxseg;
3686 } else
3687 cwnd = maxseg;
3688 flight = ctf_flight_size(tp,
3689 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
3690 bbr_log_type_cwndupd(bbr, flight, 0,
3691 losses, 10, 0, 0, line);
3692 if (bbr->pkt_conservation) {
3693 uint32_t time_in;
3694
3695 if (TSTMP_GEQ(bbr->r_ctl.rc_rcvtime, bbr->r_ctl.rc_recovery_start))
3696 time_in = bbr->r_ctl.rc_rcvtime - bbr->r_ctl.rc_recovery_start;
3697 else
3698 time_in = 0;
3699
3700 if (time_in >= bbr_get_rtt(bbr, BBR_RTT_PROP)) {
3701 /* Clear packet conservation after an rttProp */
3702 bbr->pkt_conservation = 0;
3703 } else {
3704 if ((flight + bytes_this_ack) > cwnd)
3705 cwnd = flight + bytes_this_ack;
3706 if (cwnd < get_min_cwnd(bbr))
3707 cwnd = get_min_cwnd(bbr);
3708 tp->snd_cwnd = cwnd;
3709 bbr_log_type_cwndupd(bbr, saved_bytes, sack_changed,
3710 prev_acked, 1, target_cwnd, th->th_ack, line);
3711 return;
3712 }
3713 }
3714 } else
3715 bbr->bbr_prev_in_rec = 0;
3716 if ((bbr->rc_use_google == 0) && bbr->r_ctl.restrict_growth) {
3717 bbr->r_ctl.restrict_growth--;
3718 if (bytes_this_ack > maxseg)
3719 bytes_this_ack = maxseg;
3720 }
3721 if (bbr->rc_filled_pipe) {
3722 /*
3723 * Here we have exited startup and filled the pipe. We will
3724 * thus allow the cwnd to shrink to the target. We hit here
3725 * mostly.
3726 */
3727 uint32_t s_cwnd;
3728
3729 meth = 2;
3730 s_cwnd = min((cwnd + bytes_this_ack), target_cwnd);
3731 if (s_cwnd > cwnd)
3732 cwnd = s_cwnd;
3733 else if (bbr_cwnd_may_shrink || bbr->rc_use_google || bbr->rc_no_pacing)
3734 cwnd = s_cwnd;
3735 } else {
3736 /*
3737 * Here we are still in startup, we increase cwnd by what
3738 * has been acked.
3739 */
3740 if ((cwnd < target_cwnd) ||
3741 (bbr->rc_past_init_win == 0)) {
3742 meth = 3;
3743 cwnd += bytes_this_ack;
3744 } else {
3745 /*
3746 * Method 4 means we are at target so no gain in
3747 * startup and past the initial window.
3748 */
3749 meth = 4;
3750 }
3751 }
3752 tp->snd_cwnd = max(cwnd, get_min_cwnd(bbr));
3753 bbr_log_type_cwndupd(bbr, saved_bytes, sack_changed, prev_acked, meth, target_cwnd, th->th_ack, line);
3754 }
3755
3756 static void
3757 tcp_bbr_partialack(struct tcpcb *tp)
3758 {
3759 struct tcp_bbr *bbr;
3760
3761 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
3762 INP_WLOCK_ASSERT(tptoinpcb(tp));
3763 if (ctf_flight_size(tp,
3764 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) <=
3765 tp->snd_cwnd) {
3766 bbr->r_wanted_output = 1;
3767 }
3768 }
3769
3770 static void
3771 bbr_post_recovery(struct tcpcb *tp)
3772 {
3773 struct tcp_bbr *bbr;
3774 uint32_t flight;
3775
3776 INP_WLOCK_ASSERT(tptoinpcb(tp));
3777 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
3778 /*
3779 * Here we just exit recovery.
3780 */
3781 EXIT_RECOVERY(tp->t_flags);
3782 /* Lock in our b/w reduction for the specified number of pkt-epochs */
3783 bbr->r_recovery_bw = 0;
3784 tp->snd_recover = tp->snd_una;
3785 tcp_bbr_tso_size_check(bbr, bbr->r_ctl.rc_rcvtime);
3786 bbr->pkt_conservation = 0;
3787 if (bbr->rc_use_google == 0) {
3788 /*
3789 * For non-google mode lets
3790 * go ahead and make sure we clear
3791 * the recovery state so if we
3792 * bounce back in to recovery we
3793 * will do PC.
3794 */
3795 bbr->bbr_prev_in_rec = 0;
3796 }
3797 bbr_log_type_exit_rec(bbr);
3798 if (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) {
3799 tp->snd_cwnd = max(tp->snd_cwnd, bbr->r_ctl.rc_cwnd_on_ent);
3800 bbr_log_type_cwndupd(bbr, 0, 0, 0, 15, 0, 0, __LINE__);
3801 } else {
3802 /* For probe-rtt case lets fix up its saved_cwnd */
3803 if (bbr->r_ctl.rc_saved_cwnd < bbr->r_ctl.rc_cwnd_on_ent) {
3804 bbr->r_ctl.rc_saved_cwnd = bbr->r_ctl.rc_cwnd_on_ent;
3805 bbr_log_type_cwndupd(bbr, 0, 0, 0, 16, 0, 0, __LINE__);
3806 }
3807 }
3808 flight = ctf_flight_size(tp,
3809 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
3810 if ((bbr->rc_use_google == 0) &&
3811 bbr_do_red) {
3812 uint64_t val, lr2use;
3813 uint32_t maxseg, newcwnd, acks_inflight, ratio, cwnd;
3814 uint32_t *cwnd_p;
3815
3816 if (bbr_get_rtt(bbr, BBR_SRTT)) {
3817 val = ((uint64_t)bbr_get_rtt(bbr, BBR_RTT_PROP) * (uint64_t)1000);
3818 val /= bbr_get_rtt(bbr, BBR_SRTT);
3819 ratio = (uint32_t)val;
3820 } else
3821 ratio = 1000;
3822
3823 bbr_log_type_cwndupd(bbr, bbr_red_mul, bbr_red_div,
3824 bbr->r_ctl.recovery_lr, 21,
3825 ratio,
3826 bbr->r_ctl.rc_red_cwnd_pe,
3827 __LINE__);
3828 if ((ratio < bbr_do_red) || (bbr_do_red == 0))
3829 goto done;
3830 if (((bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) &&
3831 bbr_prtt_slam_cwnd) ||
3832 (bbr_sub_drain_slam_cwnd &&
3833 (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) &&
3834 bbr->rc_hit_state_1 &&
3835 (bbr_state_val(bbr) == BBR_SUB_DRAIN)) ||
3836 ((bbr->rc_bbr_state == BBR_STATE_DRAIN) &&
3837 bbr_slam_cwnd_in_main_drain)) {
3838 /*
3839 * Here we must poke at the saved cwnd
3840 * as well as the cwnd.
3841 */
3842 cwnd = bbr->r_ctl.rc_saved_cwnd;
3843 cwnd_p = &bbr->r_ctl.rc_saved_cwnd;
3844 } else {
3845 cwnd = tp->snd_cwnd;
3846 cwnd_p = &tp->snd_cwnd;
3847 }
3848 maxseg = tp->t_maxseg - bbr->rc_last_options;
3849 /* Add the overall lr with the recovery lr */
3850 if (bbr->r_ctl.rc_lost == 0)
3851 lr2use = 0;
3852 else if (bbr->r_ctl.rc_delivered == 0)
3853 lr2use = 1000;
3854 else {
3855 lr2use = bbr->r_ctl.rc_lost * 1000;
3856 lr2use /= bbr->r_ctl.rc_delivered;
3857 }
3858 lr2use += bbr->r_ctl.recovery_lr;
3859 acks_inflight = (flight / (maxseg * 2));
3860 if (bbr_red_scale) {
3861 lr2use *= bbr_get_rtt(bbr, BBR_SRTT);
3862 lr2use /= bbr_red_scale;
3863 if ((bbr_red_growth_restrict) &&
3864 ((bbr_get_rtt(bbr, BBR_SRTT)/bbr_red_scale) > 1))
3865 bbr->r_ctl.restrict_growth += acks_inflight;
3866 }
3867 if (lr2use) {
3868 val = (uint64_t)cwnd * lr2use;
3869 val /= 1000;
3870 if (cwnd > val)
3871 newcwnd = roundup((cwnd - val), maxseg);
3872 else
3873 newcwnd = maxseg;
3874 } else {
3875 val = (uint64_t)cwnd * (uint64_t)bbr_red_mul;
3876 val /= (uint64_t)bbr_red_div;
3877 newcwnd = roundup((uint32_t)val, maxseg);
3878 }
3879 /* with standard delayed acks how many acks can I expect? */
3880 if (bbr_drop_limit == 0) {
3881 /*
3882 * Anticpate how much we will
3883 * raise the cwnd based on the acks.
3884 */
3885 if ((newcwnd + (acks_inflight * maxseg)) < get_min_cwnd(bbr)) {
3886 /* We do enforce the min (with the acks) */
3887 newcwnd = (get_min_cwnd(bbr) - acks_inflight);
3888 }
3889 } else {
3890 /*
3891 * A strict drop limit of N is inplace
3892 */
3893 if (newcwnd < (bbr_drop_limit * maxseg)) {
3894 newcwnd = bbr_drop_limit * maxseg;
3895 }
3896 }
3897 /* For the next N acks do we restrict the growth */
3898 *cwnd_p = newcwnd;
3899 if (tp->snd_cwnd > newcwnd)
3900 tp->snd_cwnd = newcwnd;
3901 bbr_log_type_cwndupd(bbr, bbr_red_mul, bbr_red_div, val, 22,
3902 (uint32_t)lr2use,
3903 bbr_get_rtt(bbr, BBR_SRTT), __LINE__);
3904 bbr->r_ctl.rc_red_cwnd_pe = bbr->r_ctl.rc_pkt_epoch;
3905 }
3906 done:
3907 bbr->r_ctl.recovery_lr = 0;
3908 if (flight <= tp->snd_cwnd) {
3909 bbr->r_wanted_output = 1;
3910 }
3911 tcp_bbr_tso_size_check(bbr, bbr->r_ctl.rc_rcvtime);
3912 }
3913
3914 static void
3915 bbr_setup_red_bw(struct tcp_bbr *bbr, uint32_t cts)
3916 {
3917 bbr->r_ctl.red_bw = get_filter_value(&bbr->r_ctl.rc_delrate);
3918 /* Limit the drop in b/w to 1/2 our current filter. */
3919 if (bbr->r_ctl.red_bw > bbr->r_ctl.rc_bbr_cur_del_rate)
3920 bbr->r_ctl.red_bw = bbr->r_ctl.rc_bbr_cur_del_rate;
3921 if (bbr->r_ctl.red_bw < (get_filter_value(&bbr->r_ctl.rc_delrate) / 2))
3922 bbr->r_ctl.red_bw = get_filter_value(&bbr->r_ctl.rc_delrate) / 2;
3923 tcp_bbr_tso_size_check(bbr, cts);
3924 }
3925
3926 static void
3927 bbr_cong_signal(struct tcpcb *tp, struct tcphdr *th, uint32_t type, struct bbr_sendmap *rsm)
3928 {
3929 struct tcp_bbr *bbr;
3930
3931 INP_WLOCK_ASSERT(tptoinpcb(tp));
3932 #ifdef STATS
3933 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_CSIG, type);
3934 #endif
3935 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
3936 switch (type) {
3937 case CC_NDUPACK:
3938 if (!IN_RECOVERY(tp->t_flags)) {
3939 tp->snd_recover = tp->snd_max;
3940 /* Start a new epoch */
3941 bbr_set_pktepoch(bbr, bbr->r_ctl.rc_rcvtime, __LINE__);
3942 if (bbr->rc_lt_is_sampling || bbr->rc_lt_use_bw) {
3943 /*
3944 * Move forward the lt epoch
3945 * so it won't count the truncated
3946 * epoch.
3947 */
3948 bbr->r_ctl.rc_lt_epoch++;
3949 }
3950 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) {
3951 /*
3952 * Just like the policer detection code
3953 * if we are in startup we must push
3954 * forward the last startup epoch
3955 * to hide the truncated PE.
3956 */
3957 bbr->r_ctl.rc_bbr_last_startup_epoch++;
3958 }
3959 bbr->r_ctl.rc_cwnd_on_ent = tp->snd_cwnd;
3960 ENTER_RECOVERY(tp->t_flags);
3961 bbr->rc_tlp_rtx_out = 0;
3962 bbr->r_ctl.recovery_lr = bbr->r_ctl.rc_pkt_epoch_loss_rate;
3963 tcp_bbr_tso_size_check(bbr, bbr->r_ctl.rc_rcvtime);
3964 if (tcp_in_hpts(bbr->rc_inp) &&
3965 ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK) == 0)) {
3966 /*
3967 * When we enter recovery, we need to restart
3968 * any timers. This may mean we gain an agg
3969 * early, which will be made up for at the last
3970 * rxt out.
3971 */
3972 bbr->rc_timer_first = 1;
3973 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime);
3974 }
3975 /*
3976 * Calculate a new cwnd based on to the current
3977 * delivery rate with no gain. We get the bdp
3978 * without gaining it up like we normally would and
3979 * we use the last cur_del_rate.
3980 */
3981 if ((bbr->rc_use_google == 0) &&
3982 (bbr->r_ctl.bbr_rttprobe_gain_val ||
3983 (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT))) {
3984 tp->snd_cwnd = ctf_flight_size(tp,
3985 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) +
3986 (tp->t_maxseg - bbr->rc_last_options);
3987 if (tp->snd_cwnd < get_min_cwnd(bbr)) {
3988 /* We always gate to min cwnd */
3989 tp->snd_cwnd = get_min_cwnd(bbr);
3990 }
3991 bbr_log_type_cwndupd(bbr, 0, 0, 0, 14, 0, 0, __LINE__);
3992 }
3993 bbr_log_type_enter_rec(bbr, rsm->r_start);
3994 }
3995 break;
3996 case CC_RTO_ERR:
3997 KMOD_TCPSTAT_INC(tcps_sndrexmitbad);
3998 /* RTO was unnecessary, so reset everything. */
3999 bbr_reset_lt_bw_sampling(bbr, bbr->r_ctl.rc_rcvtime);
4000 if (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) {
4001 tp->snd_cwnd = tp->snd_cwnd_prev;
4002 tp->snd_ssthresh = tp->snd_ssthresh_prev;
4003 tp->snd_recover = tp->snd_recover_prev;
4004 tp->snd_cwnd = max(tp->snd_cwnd, bbr->r_ctl.rc_cwnd_on_ent);
4005 bbr_log_type_cwndupd(bbr, 0, 0, 0, 13, 0, 0, __LINE__);
4006 }
4007 tp->t_badrxtwin = 0;
4008 break;
4009 }
4010 }
4011
4012 /*
4013 * Indicate whether this ack should be delayed. We can delay the ack if
4014 * following conditions are met:
4015 * - There is no delayed ack timer in progress.
4016 * - Our last ack wasn't a 0-sized window. We never want to delay
4017 * the ack that opens up a 0-sized window.
4018 * - LRO wasn't used for this segment. We make sure by checking that the
4019 * segment size is not larger than the MSS.
4020 * - Delayed acks are enabled or this is a half-synchronized T/TCP
4021 * connection.
4022 * - The data being acked is less than a full segment (a stretch ack
4023 * of more than a segment we should ack.
4024 * - nsegs is 1 (if its more than that we received more than 1 ack).
4025 */
4026 #define DELAY_ACK(tp, bbr, nsegs) \
4027 (((tp->t_flags & TF_RXWIN0SENT) == 0) && \
4028 ((tp->t_flags & TF_DELACK) == 0) && \
4029 ((bbr->bbr_segs_rcvd + nsegs) < tp->t_delayed_ack) && \
4030 (tp->t_delayed_ack || (tp->t_flags & TF_NEEDSYN)))
4031
4032 /*
4033 * Return the lowest RSM in the map of
4034 * packets still in flight that is not acked.
4035 * This should normally find on the first one
4036 * since we remove packets from the send
4037 * map after they are marked ACKED.
4038 */
4039 static struct bbr_sendmap *
4040 bbr_find_lowest_rsm(struct tcp_bbr *bbr)
4041 {
4042 struct bbr_sendmap *rsm;
4043
4044 /*
4045 * Walk the time-order transmitted list looking for an rsm that is
4046 * not acked. This will be the one that was sent the longest time
4047 * ago that is still outstanding.
4048 */
4049 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_tmap, r_tnext) {
4050 if (rsm->r_flags & BBR_ACKED) {
4051 continue;
4052 }
4053 goto finish;
4054 }
4055 finish:
4056 return (rsm);
4057 }
4058
4059 static struct bbr_sendmap *
4060 bbr_find_high_nonack(struct tcp_bbr *bbr, struct bbr_sendmap *rsm)
4061 {
4062 struct bbr_sendmap *prsm;
4063
4064 /*
4065 * Walk the sequence order list backward until we hit and arrive at
4066 * the highest seq not acked. In theory when this is called it
4067 * should be the last segment (which it was not).
4068 */
4069 prsm = rsm;
4070 TAILQ_FOREACH_REVERSE_FROM(prsm, &bbr->r_ctl.rc_map, bbr_head, r_next) {
4071 if (prsm->r_flags & (BBR_ACKED | BBR_HAS_FIN)) {
4072 continue;
4073 }
4074 return (prsm);
4075 }
4076 return (NULL);
4077 }
4078
4079 /*
4080 * Returns to the caller the number of microseconds that
4081 * the packet can be outstanding before we think we
4082 * should have had an ack returned.
4083 */
4084 static uint32_t
4085 bbr_calc_thresh_rack(struct tcp_bbr *bbr, uint32_t srtt, uint32_t cts, struct bbr_sendmap *rsm)
4086 {
4087 /*
4088 * lro is the flag we use to determine if we have seen reordering.
4089 * If it gets set we have seen reordering. The reorder logic either
4090 * works in one of two ways:
4091 *
4092 * If reorder-fade is configured, then we track the last time we saw
4093 * re-ordering occur. If we reach the point where enough time as
4094 * passed we no longer consider reordering has occuring.
4095 *
4096 * Or if reorder-face is 0, then once we see reordering we consider
4097 * the connection to alway be subject to reordering and just set lro
4098 * to 1.
4099 *
4100 * In the end if lro is non-zero we add the extra time for
4101 * reordering in.
4102 */
4103 int32_t lro;
4104 uint32_t thresh, t_rxtcur;
4105
4106 if (srtt == 0)
4107 srtt = 1;
4108 if (bbr->r_ctl.rc_reorder_ts) {
4109 if (bbr->r_ctl.rc_reorder_fade) {
4110 if (SEQ_GEQ(cts, bbr->r_ctl.rc_reorder_ts)) {
4111 lro = cts - bbr->r_ctl.rc_reorder_ts;
4112 if (lro == 0) {
4113 /*
4114 * No time as passed since the last
4115 * reorder, mark it as reordering.
4116 */
4117 lro = 1;
4118 }
4119 } else {
4120 /* Negative time? */
4121 lro = 0;
4122 }
4123 if (lro > bbr->r_ctl.rc_reorder_fade) {
4124 /* Turn off reordering seen too */
4125 bbr->r_ctl.rc_reorder_ts = 0;
4126 lro = 0;
4127 }
4128 } else {
4129 /* Reodering does not fade */
4130 lro = 1;
4131 }
4132 } else {
4133 lro = 0;
4134 }
4135 thresh = srtt + bbr->r_ctl.rc_pkt_delay;
4136 if (lro) {
4137 /* It must be set, if not you get 1/4 rtt */
4138 if (bbr->r_ctl.rc_reorder_shift)
4139 thresh += (srtt >> bbr->r_ctl.rc_reorder_shift);
4140 else
4141 thresh += (srtt >> 2);
4142 } else {
4143 thresh += 1000;
4144 }
4145 /* We don't let the rack timeout be above a RTO */
4146 if ((bbr->rc_tp)->t_srtt == 0)
4147 t_rxtcur = BBR_INITIAL_RTO;
4148 else
4149 t_rxtcur = TICKS_2_USEC(bbr->rc_tp->t_rxtcur);
4150 if (thresh > t_rxtcur) {
4151 thresh = t_rxtcur;
4152 }
4153 /* And we don't want it above the RTO max either */
4154 if (thresh > (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND)) {
4155 thresh = (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND);
4156 }
4157 bbr_log_thresh_choice(bbr, cts, thresh, lro, srtt, rsm, BBR_TO_FRM_RACK);
4158 return (thresh);
4159 }
4160
4161 /*
4162 * Return to the caller the amount of time in mico-seconds
4163 * that should be used for the TLP timer from the last
4164 * send time of this packet.
4165 */
4166 static uint32_t
4167 bbr_calc_thresh_tlp(struct tcpcb *tp, struct tcp_bbr *bbr,
4168 struct bbr_sendmap *rsm, uint32_t srtt,
4169 uint32_t cts)
4170 {
4171 uint32_t thresh, len, maxseg, t_rxtcur;
4172 struct bbr_sendmap *prsm;
4173
4174 if (srtt == 0)
4175 srtt = 1;
4176 if (bbr->rc_tlp_threshold)
4177 thresh = srtt + (srtt / bbr->rc_tlp_threshold);
4178 else
4179 thresh = (srtt * 2);
4180 maxseg = tp->t_maxseg - bbr->rc_last_options;
4181 /* Get the previous sent packet, if any */
4182 len = rsm->r_end - rsm->r_start;
4183
4184 /* 2.1 behavior */
4185 prsm = TAILQ_PREV(rsm, bbr_head, r_tnext);
4186 if (prsm && (len <= maxseg)) {
4187 /*
4188 * Two packets outstanding, thresh should be (2*srtt) +
4189 * possible inter-packet delay (if any).
4190 */
4191 uint32_t inter_gap = 0;
4192 int idx, nidx;
4193
4194 idx = rsm->r_rtr_cnt - 1;
4195 nidx = prsm->r_rtr_cnt - 1;
4196 if (TSTMP_GEQ(rsm->r_tim_lastsent[nidx], prsm->r_tim_lastsent[idx])) {
4197 /* Yes it was sent later (or at the same time) */
4198 inter_gap = rsm->r_tim_lastsent[idx] - prsm->r_tim_lastsent[nidx];
4199 }
4200 thresh += inter_gap;
4201 } else if (len <= maxseg) {
4202 /*
4203 * Possibly compensate for delayed-ack.
4204 */
4205 uint32_t alt_thresh;
4206
4207 alt_thresh = srtt + (srtt / 2) + bbr_delayed_ack_time;
4208 if (alt_thresh > thresh)
4209 thresh = alt_thresh;
4210 }
4211 /* Not above the current RTO */
4212 if (tp->t_srtt == 0)
4213 t_rxtcur = BBR_INITIAL_RTO;
4214 else
4215 t_rxtcur = TICKS_2_USEC(tp->t_rxtcur);
4216
4217 bbr_log_thresh_choice(bbr, cts, thresh, t_rxtcur, srtt, rsm, BBR_TO_FRM_TLP);
4218 /* Not above an RTO */
4219 if (thresh > t_rxtcur) {
4220 thresh = t_rxtcur;
4221 }
4222 /* Not above a RTO max */
4223 if (thresh > (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND)) {
4224 thresh = (((uint32_t)bbr->rc_max_rto_sec) * USECS_IN_SECOND);
4225 }
4226 /* And now apply the user TLP min */
4227 if (thresh < bbr_tlp_min) {
4228 thresh = bbr_tlp_min;
4229 }
4230 return (thresh);
4231 }
4232
4233 /*
4234 * Return one of three RTTs to use (in microseconds).
4235 */
4236 static __inline uint32_t
4237 bbr_get_rtt(struct tcp_bbr *bbr, int32_t rtt_type)
4238 {
4239 uint32_t f_rtt;
4240 uint32_t srtt;
4241
4242 f_rtt = get_filter_value_small(&bbr->r_ctl.rc_rttprop);
4243 if (get_filter_value_small(&bbr->r_ctl.rc_rttprop) == 0xffffffff) {
4244 /* We have no rtt at all */
4245 if (bbr->rc_tp->t_srtt == 0)
4246 f_rtt = BBR_INITIAL_RTO;
4247 else
4248 f_rtt = (TICKS_2_USEC(bbr->rc_tp->t_srtt) >> TCP_RTT_SHIFT);
4249 /*
4250 * Since we don't know how good the rtt is apply a
4251 * delayed-ack min
4252 */
4253 if (f_rtt < bbr_delayed_ack_time) {
4254 f_rtt = bbr_delayed_ack_time;
4255 }
4256 }
4257 /* Take the filter version or last measured pkt-rtt */
4258 if (rtt_type == BBR_RTT_PROP) {
4259 srtt = f_rtt;
4260 } else if (rtt_type == BBR_RTT_PKTRTT) {
4261 if (bbr->r_ctl.rc_pkt_epoch_rtt) {
4262 srtt = bbr->r_ctl.rc_pkt_epoch_rtt;
4263 } else {
4264 /* No pkt rtt yet */
4265 srtt = f_rtt;
4266 }
4267 } else if (rtt_type == BBR_RTT_RACK) {
4268 srtt = bbr->r_ctl.rc_last_rtt;
4269 /* We need to add in any internal delay for our timer */
4270 if (bbr->rc_ack_was_delayed)
4271 srtt += bbr->r_ctl.rc_ack_hdwr_delay;
4272 } else if (rtt_type == BBR_SRTT) {
4273 srtt = (TICKS_2_USEC(bbr->rc_tp->t_srtt) >> TCP_RTT_SHIFT);
4274 } else {
4275 /* TSNH */
4276 srtt = f_rtt;
4277 #ifdef BBR_INVARIANTS
4278 panic("Unknown rtt request type %d", rtt_type);
4279 #endif
4280 }
4281 return (srtt);
4282 }
4283
4284 static int
4285 bbr_is_lost(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t cts)
4286 {
4287 uint32_t thresh;
4288
4289 thresh = bbr_calc_thresh_rack(bbr, bbr_get_rtt(bbr, BBR_RTT_RACK),
4290 cts, rsm);
4291 if ((cts - rsm->r_tim_lastsent[(rsm->r_rtr_cnt - 1)]) >= thresh) {
4292 /* It is lost (past time) */
4293 return (1);
4294 }
4295 return (0);
4296 }
4297
4298 /*
4299 * Return a sendmap if we need to retransmit something.
4300 */
4301 static struct bbr_sendmap *
4302 bbr_check_recovery_mode(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts)
4303 {
4304 /*
4305 * Check to see that we don't need to fall into recovery. We will
4306 * need to do so if our oldest transmit is past the time we should
4307 * have had an ack.
4308 */
4309
4310 struct bbr_sendmap *rsm;
4311 int32_t idx;
4312
4313 if (TAILQ_EMPTY(&bbr->r_ctl.rc_map)) {
4314 /* Nothing outstanding that we know of */
4315 return (NULL);
4316 }
4317 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap);
4318 if (rsm == NULL) {
4319 /* Nothing in the transmit map */
4320 return (NULL);
4321 }
4322 if (tp->t_flags & TF_SENTFIN) {
4323 /* Fin restricted, don't find anything once a fin is sent */
4324 return (NULL);
4325 }
4326 if (rsm->r_flags & BBR_ACKED) {
4327 /*
4328 * Ok the first one is acked (this really should not happen
4329 * since we remove the from the tmap once they are acked)
4330 */
4331 rsm = bbr_find_lowest_rsm(bbr);
4332 if (rsm == NULL)
4333 return (NULL);
4334 }
4335 idx = rsm->r_rtr_cnt - 1;
4336 if (SEQ_LEQ(cts, rsm->r_tim_lastsent[idx])) {
4337 /* Send timestamp is the same or less? can't be ready */
4338 return (NULL);
4339 }
4340 /* Get our RTT time */
4341 if (bbr_is_lost(bbr, rsm, cts) &&
4342 ((rsm->r_dupack >= DUP_ACK_THRESHOLD) ||
4343 (rsm->r_flags & BBR_SACK_PASSED))) {
4344 if ((rsm->r_flags & BBR_MARKED_LOST) == 0) {
4345 rsm->r_flags |= BBR_MARKED_LOST;
4346 bbr->r_ctl.rc_lost += rsm->r_end - rsm->r_start;
4347 bbr->r_ctl.rc_lost_bytes += rsm->r_end - rsm->r_start;
4348 }
4349 bbr_cong_signal(tp, NULL, CC_NDUPACK, rsm);
4350 #ifdef BBR_INVARIANTS
4351 if ((rsm->r_end - rsm->r_start) == 0)
4352 panic("tp:%p bbr:%p rsm:%p length is 0?", tp, bbr, rsm);
4353 #endif
4354 return (rsm);
4355 }
4356 return (NULL);
4357 }
4358
4359 /*
4360 * RACK Timer, here we simply do logging and house keeping.
4361 * the normal bbr_output_wtime() function will call the
4362 * appropriate thing to check if we need to do a RACK retransmit.
4363 * We return 1, saying don't proceed with bbr_output_wtime only
4364 * when all timers have been stopped (destroyed PCB?).
4365 */
4366 static int
4367 bbr_timeout_rack(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts)
4368 {
4369 /*
4370 * This timer simply provides an internal trigger to send out data.
4371 * The check_recovery_mode call will see if there are needed
4372 * retransmissions, if so we will enter fast-recovery. The output
4373 * call may or may not do the same thing depending on sysctl
4374 * settings.
4375 */
4376 uint32_t lost;
4377
4378 if (bbr->rc_all_timers_stopped) {
4379 return (1);
4380 }
4381 if (TSTMP_LT(cts, bbr->r_ctl.rc_timer_exp)) {
4382 /* Its not time yet */
4383 return (0);
4384 }
4385 BBR_STAT_INC(bbr_to_tot);
4386 lost = bbr->r_ctl.rc_lost;
4387 if (bbr->r_state && (bbr->r_state != tp->t_state))
4388 bbr_set_state(tp, bbr, 0);
4389 bbr_log_to_event(bbr, cts, BBR_TO_FRM_RACK);
4390 if (bbr->r_ctl.rc_resend == NULL) {
4391 /* Lets do the check here */
4392 bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts);
4393 }
4394 if (bbr_policer_call_from_rack_to)
4395 bbr_lt_bw_sampling(bbr, cts, (bbr->r_ctl.rc_lost > lost));
4396 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_RACK;
4397 return (0);
4398 }
4399
4400 static __inline void
4401 bbr_clone_rsm(struct tcp_bbr *bbr, struct bbr_sendmap *nrsm, struct bbr_sendmap *rsm, uint32_t start)
4402 {
4403 int idx;
4404
4405 nrsm->r_start = start;
4406 nrsm->r_end = rsm->r_end;
4407 nrsm->r_rtr_cnt = rsm->r_rtr_cnt;
4408 nrsm-> r_rtt_not_allowed = rsm->r_rtt_not_allowed;
4409 nrsm->r_flags = rsm->r_flags;
4410 /* We don't transfer forward the SYN flag */
4411 nrsm->r_flags &= ~BBR_HAS_SYN;
4412 /* We move forward the FIN flag, not that this should happen */
4413 rsm->r_flags &= ~BBR_HAS_FIN;
4414 nrsm->r_dupack = rsm->r_dupack;
4415 nrsm->r_rtr_bytes = 0;
4416 nrsm->r_is_gain = rsm->r_is_gain;
4417 nrsm->r_is_drain = rsm->r_is_drain;
4418 nrsm->r_delivered = rsm->r_delivered;
4419 nrsm->r_ts_valid = rsm->r_ts_valid;
4420 nrsm->r_del_ack_ts = rsm->r_del_ack_ts;
4421 nrsm->r_del_time = rsm->r_del_time;
4422 nrsm->r_app_limited = rsm->r_app_limited;
4423 nrsm->r_first_sent_time = rsm->r_first_sent_time;
4424 nrsm->r_flight_at_send = rsm->r_flight_at_send;
4425 /* We split a piece the lower section looses any just_ret flag. */
4426 nrsm->r_bbr_state = rsm->r_bbr_state;
4427 for (idx = 0; idx < nrsm->r_rtr_cnt; idx++) {
4428 nrsm->r_tim_lastsent[idx] = rsm->r_tim_lastsent[idx];
4429 }
4430 rsm->r_end = nrsm->r_start;
4431 idx = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options), bbr->r_ctl.rc_pace_max_segs);
4432 idx /= 8;
4433 /* Check if we got too small */
4434 if ((rsm->r_is_smallmap == 0) &&
4435 ((rsm->r_end - rsm->r_start) <= idx)) {
4436 bbr->r_ctl.rc_num_small_maps_alloced++;
4437 rsm->r_is_smallmap = 1;
4438 }
4439 /* Check the new one as well */
4440 if ((nrsm->r_end - nrsm->r_start) <= idx) {
4441 bbr->r_ctl.rc_num_small_maps_alloced++;
4442 nrsm->r_is_smallmap = 1;
4443 }
4444 }
4445
4446 static int
4447 bbr_sack_mergable(struct bbr_sendmap *at,
4448 uint32_t start, uint32_t end)
4449 {
4450 /*
4451 * Given a sack block defined by
4452 * start and end, and a current position
4453 * at. Return 1 if either side of at
4454 * would show that the block is mergable
4455 * to that side. A block to be mergable
4456 * must have overlap with the start/end
4457 * and be in the SACK'd state.
4458 */
4459 struct bbr_sendmap *l_rsm;
4460 struct bbr_sendmap *r_rsm;
4461
4462 /* first get the either side blocks */
4463 l_rsm = TAILQ_PREV(at, bbr_head, r_next);
4464 r_rsm = TAILQ_NEXT(at, r_next);
4465 if (l_rsm && (l_rsm->r_flags & BBR_ACKED)) {
4466 /* Potentially mergeable */
4467 if ((l_rsm->r_end == start) ||
4468 (SEQ_LT(start, l_rsm->r_end) &&
4469 SEQ_GT(end, l_rsm->r_end))) {
4470 /*
4471 * map blk |------|
4472 * sack blk |------|
4473 * <or>
4474 * map blk |------|
4475 * sack blk |------|
4476 */
4477 return (1);
4478 }
4479 }
4480 if (r_rsm && (r_rsm->r_flags & BBR_ACKED)) {
4481 /* Potentially mergeable */
4482 if ((r_rsm->r_start == end) ||
4483 (SEQ_LT(start, r_rsm->r_start) &&
4484 SEQ_GT(end, r_rsm->r_start))) {
4485 /*
4486 * map blk |---------|
4487 * sack blk |----|
4488 * <or>
4489 * map blk |---------|
4490 * sack blk |-------|
4491 */
4492 return (1);
4493 }
4494 }
4495 return (0);
4496 }
4497
4498 static struct bbr_sendmap *
4499 bbr_merge_rsm(struct tcp_bbr *bbr,
4500 struct bbr_sendmap *l_rsm,
4501 struct bbr_sendmap *r_rsm)
4502 {
4503 /*
4504 * We are merging two ack'd RSM's,
4505 * the l_rsm is on the left (lower seq
4506 * values) and the r_rsm is on the right
4507 * (higher seq value). The simplest way
4508 * to merge these is to move the right
4509 * one into the left. I don't think there
4510 * is any reason we need to try to find
4511 * the oldest (or last oldest retransmitted).
4512 */
4513 l_rsm->r_end = r_rsm->r_end;
4514 if (l_rsm->r_dupack < r_rsm->r_dupack)
4515 l_rsm->r_dupack = r_rsm->r_dupack;
4516 if (r_rsm->r_rtr_bytes)
4517 l_rsm->r_rtr_bytes += r_rsm->r_rtr_bytes;
4518 if (r_rsm->r_in_tmap) {
4519 /* This really should not happen */
4520 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, r_rsm, r_tnext);
4521 }
4522 if (r_rsm->r_app_limited)
4523 l_rsm->r_app_limited = r_rsm->r_app_limited;
4524 /* Now the flags */
4525 if (r_rsm->r_flags & BBR_HAS_FIN)
4526 l_rsm->r_flags |= BBR_HAS_FIN;
4527 if (r_rsm->r_flags & BBR_TLP)
4528 l_rsm->r_flags |= BBR_TLP;
4529 if (r_rsm->r_flags & BBR_RWND_COLLAPSED)
4530 l_rsm->r_flags |= BBR_RWND_COLLAPSED;
4531 if (r_rsm->r_flags & BBR_MARKED_LOST) {
4532 /* This really should not happen */
4533 bbr->r_ctl.rc_lost_bytes -= r_rsm->r_end - r_rsm->r_start;
4534 }
4535 TAILQ_REMOVE(&bbr->r_ctl.rc_map, r_rsm, r_next);
4536 if ((r_rsm->r_limit_type == 0) && (l_rsm->r_limit_type != 0)) {
4537 /* Transfer the split limit to the map we free */
4538 r_rsm->r_limit_type = l_rsm->r_limit_type;
4539 l_rsm->r_limit_type = 0;
4540 }
4541 bbr_free(bbr, r_rsm);
4542 return(l_rsm);
4543 }
4544
4545 /*
4546 * TLP Timer, here we simply setup what segment we want to
4547 * have the TLP expire on, the normal bbr_output_wtime() will then
4548 * send it out.
4549 *
4550 * We return 1, saying don't proceed with bbr_output_wtime only
4551 * when all timers have been stopped (destroyed PCB?).
4552 */
4553 static int
4554 bbr_timeout_tlp(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts)
4555 {
4556 /*
4557 * Tail Loss Probe.
4558 */
4559 struct bbr_sendmap *rsm = NULL;
4560 struct socket *so;
4561 uint32_t amm;
4562 uint32_t out, avail;
4563 uint32_t maxseg;
4564 int collapsed_win = 0;
4565
4566 if (bbr->rc_all_timers_stopped) {
4567 return (1);
4568 }
4569 if (TSTMP_LT(cts, bbr->r_ctl.rc_timer_exp)) {
4570 /* Its not time yet */
4571 return (0);
4572 }
4573 if (ctf_progress_timeout_check(tp, true)) {
4574 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__);
4575 return (-ETIMEDOUT); /* tcp_drop() */
4576 }
4577 /* Did we somehow get into persists? */
4578 if (bbr->rc_in_persist) {
4579 return (0);
4580 }
4581 if (bbr->r_state && (bbr->r_state != tp->t_state))
4582 bbr_set_state(tp, bbr, 0);
4583 BBR_STAT_INC(bbr_tlp_tot);
4584 maxseg = tp->t_maxseg - bbr->rc_last_options;
4585 /*
4586 * A TLP timer has expired. We have been idle for 2 rtts. So we now
4587 * need to figure out how to force a full MSS segment out.
4588 */
4589 so = tptosocket(tp);
4590 avail = sbavail(&so->so_snd);
4591 out = ctf_outstanding(tp);
4592 if (out > tp->snd_wnd) {
4593 /* special case, we need a retransmission */
4594 collapsed_win = 1;
4595 goto need_retran;
4596 }
4597 if (avail > out) {
4598 /* New data is available */
4599 amm = avail - out;
4600 if (amm > maxseg) {
4601 amm = maxseg;
4602 } else if ((amm < maxseg) && ((tp->t_flags & TF_NODELAY) == 0)) {
4603 /* not enough to fill a MTU and no-delay is off */
4604 goto need_retran;
4605 }
4606 /* Set the send-new override */
4607 if ((out + amm) <= tp->snd_wnd) {
4608 bbr->rc_tlp_new_data = 1;
4609 } else {
4610 goto need_retran;
4611 }
4612 bbr->r_ctl.rc_tlp_seg_send_cnt = 0;
4613 bbr->r_ctl.rc_last_tlp_seq = tp->snd_max;
4614 bbr->r_ctl.rc_tlp_send = NULL;
4615 /* cap any slots */
4616 BBR_STAT_INC(bbr_tlp_newdata);
4617 goto send;
4618 }
4619 need_retran:
4620 /*
4621 * Ok we need to arrange the last un-acked segment to be re-sent, or
4622 * optionally the first un-acked segment.
4623 */
4624 if (collapsed_win == 0) {
4625 rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_map, bbr_sendmap, r_next);
4626 if (rsm && (BBR_ACKED | BBR_HAS_FIN)) {
4627 rsm = bbr_find_high_nonack(bbr, rsm);
4628 }
4629 if (rsm == NULL) {
4630 goto restore;
4631 }
4632 } else {
4633 /*
4634 * We must find the last segment
4635 * that was acceptable by the client.
4636 */
4637 TAILQ_FOREACH_REVERSE(rsm, &bbr->r_ctl.rc_map, bbr_head, r_next) {
4638 if ((rsm->r_flags & BBR_RWND_COLLAPSED) == 0) {
4639 /* Found one */
4640 break;
4641 }
4642 }
4643 if (rsm == NULL) {
4644 /* None? if so send the first */
4645 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map);
4646 if (rsm == NULL)
4647 goto restore;
4648 }
4649 }
4650 if ((rsm->r_end - rsm->r_start) > maxseg) {
4651 /*
4652 * We need to split this the last segment in two.
4653 */
4654 struct bbr_sendmap *nrsm;
4655
4656 nrsm = bbr_alloc_full_limit(bbr);
4657 if (nrsm == NULL) {
4658 /*
4659 * We can't get memory to split, we can either just
4660 * not split it. Or retransmit the whole piece, lets
4661 * do the large send (BTLP :-) ).
4662 */
4663 goto go_for_it;
4664 }
4665 bbr_clone_rsm(bbr, nrsm, rsm, (rsm->r_end - maxseg));
4666 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next);
4667 if (rsm->r_in_tmap) {
4668 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext);
4669 nrsm->r_in_tmap = 1;
4670 }
4671 rsm->r_flags &= (~BBR_HAS_FIN);
4672 rsm = nrsm;
4673 }
4674 go_for_it:
4675 bbr->r_ctl.rc_tlp_send = rsm;
4676 bbr->rc_tlp_rtx_out = 1;
4677 if (rsm->r_start == bbr->r_ctl.rc_last_tlp_seq) {
4678 bbr->r_ctl.rc_tlp_seg_send_cnt++;
4679 tp->t_rxtshift++;
4680 } else {
4681 bbr->r_ctl.rc_last_tlp_seq = rsm->r_start;
4682 bbr->r_ctl.rc_tlp_seg_send_cnt = 1;
4683 }
4684 send:
4685 if (bbr->r_ctl.rc_tlp_seg_send_cnt > bbr_tlp_max_resend) {
4686 /*
4687 * Can't [re]/transmit a segment we have retransmitted the
4688 * max times. We need the retransmit timer to take over.
4689 */
4690 restore:
4691 bbr->rc_tlp_new_data = 0;
4692 bbr->r_ctl.rc_tlp_send = NULL;
4693 if (rsm)
4694 rsm->r_flags &= ~BBR_TLP;
4695 BBR_STAT_INC(bbr_tlp_retran_fail);
4696 return (0);
4697 } else if (rsm) {
4698 rsm->r_flags |= BBR_TLP;
4699 }
4700 if (rsm && (rsm->r_start == bbr->r_ctl.rc_last_tlp_seq) &&
4701 (bbr->r_ctl.rc_tlp_seg_send_cnt > bbr_tlp_max_resend)) {
4702 /*
4703 * We have retransmitted to many times for TLP. Switch to
4704 * the regular RTO timer
4705 */
4706 goto restore;
4707 }
4708 bbr_log_to_event(bbr, cts, BBR_TO_FRM_TLP);
4709 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_TLP;
4710 return (0);
4711 }
4712
4713 /*
4714 * Delayed ack Timer, here we simply need to setup the
4715 * ACK_NOW flag and remove the DELACK flag. From there
4716 * the output routine will send the ack out.
4717 *
4718 * We only return 1, saying don't proceed, if all timers
4719 * are stopped (destroyed PCB?).
4720 */
4721 static int
4722 bbr_timeout_delack(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts)
4723 {
4724 if (bbr->rc_all_timers_stopped) {
4725 return (1);
4726 }
4727 bbr_log_to_event(bbr, cts, BBR_TO_FRM_DELACK);
4728 tp->t_flags &= ~TF_DELACK;
4729 tp->t_flags |= TF_ACKNOW;
4730 KMOD_TCPSTAT_INC(tcps_delack);
4731 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_DELACK;
4732 return (0);
4733 }
4734
4735 /*
4736 * Here we send a KEEP-ALIVE like probe to the
4737 * peer, we do not send data.
4738 *
4739 * We only return 1, saying don't proceed, if all timers
4740 * are stopped (destroyed PCB?).
4741 */
4742 static int
4743 bbr_timeout_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts)
4744 {
4745 struct tcptemp *t_template;
4746 int32_t retval = 1;
4747
4748 if (bbr->rc_all_timers_stopped) {
4749 return (1);
4750 }
4751 if (bbr->rc_in_persist == 0)
4752 return (0);
4753
4754 /*
4755 * Persistence timer into zero window. Force a byte to be output, if
4756 * possible.
4757 */
4758 bbr_log_to_event(bbr, cts, BBR_TO_FRM_PERSIST);
4759 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_PERSIT;
4760 KMOD_TCPSTAT_INC(tcps_persisttimeo);
4761 /*
4762 * Have we exceeded the user specified progress time?
4763 */
4764 if (ctf_progress_timeout_check(tp, true)) {
4765 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__);
4766 return (-ETIMEDOUT); /* tcp_drop() */
4767 }
4768 /*
4769 * Hack: if the peer is dead/unreachable, we do not time out if the
4770 * window is closed. After a full backoff, drop the connection if
4771 * the idle time (no responses to probes) reaches the maximum
4772 * backoff that we would use if retransmitting.
4773 */
4774 if (tp->t_rxtshift == TCP_MAXRXTSHIFT &&
4775 (ticks - tp->t_rcvtime >= tcp_maxpersistidle ||
4776 ticks - tp->t_rcvtime >= TCP_REXMTVAL(tp) * tcp_totbackoff)) {
4777 KMOD_TCPSTAT_INC(tcps_persistdrop);
4778 tcp_log_end_status(tp, TCP_EI_STATUS_PERSIST_MAX);
4779 return (-ETIMEDOUT); /* tcp_drop() */
4780 }
4781 if ((sbavail(&bbr->rc_inp->inp_socket->so_snd) == 0) &&
4782 tp->snd_una == tp->snd_max) {
4783 bbr_exit_persist(tp, bbr, cts, __LINE__);
4784 retval = 0;
4785 goto out;
4786 }
4787 /*
4788 * If the user has closed the socket then drop a persisting
4789 * connection after a much reduced timeout.
4790 */
4791 if (tp->t_state > TCPS_CLOSE_WAIT &&
4792 (ticks - tp->t_rcvtime) >= TCPTV_PERSMAX) {
4793 KMOD_TCPSTAT_INC(tcps_persistdrop);
4794 tcp_log_end_status(tp, TCP_EI_STATUS_PERSIST_MAX);
4795 return (-ETIMEDOUT); /* tcp_drop() */
4796 }
4797 t_template = tcpip_maketemplate(bbr->rc_inp);
4798 if (t_template) {
4799 tcp_respond(tp, t_template->tt_ipgen,
4800 &t_template->tt_t, (struct mbuf *)NULL,
4801 tp->rcv_nxt, tp->snd_una - 1, 0);
4802 /* This sends an ack */
4803 if (tp->t_flags & TF_DELACK)
4804 tp->t_flags &= ~TF_DELACK;
4805 free(t_template, M_TEMP);
4806 }
4807 if (tp->t_rxtshift < TCP_MAXRXTSHIFT)
4808 tp->t_rxtshift++;
4809 bbr_start_hpts_timer(bbr, tp, cts, 3, 0, 0);
4810 out:
4811 return (retval);
4812 }
4813
4814 /*
4815 * If a keepalive goes off, we had no other timers
4816 * happening. We always return 1 here since this
4817 * routine either drops the connection or sends
4818 * out a segment with respond.
4819 */
4820 static int
4821 bbr_timeout_keepalive(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts)
4822 {
4823 struct tcptemp *t_template;
4824 struct inpcb *inp = tptoinpcb(tp);
4825
4826 if (bbr->rc_all_timers_stopped) {
4827 return (1);
4828 }
4829 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_KEEP;
4830 bbr_log_to_event(bbr, cts, BBR_TO_FRM_KEEP);
4831 /*
4832 * Keep-alive timer went off; send something or drop connection if
4833 * idle for too long.
4834 */
4835 KMOD_TCPSTAT_INC(tcps_keeptimeo);
4836 if (tp->t_state < TCPS_ESTABLISHED)
4837 goto dropit;
4838 if ((V_tcp_always_keepalive || inp->inp_socket->so_options & SO_KEEPALIVE) &&
4839 tp->t_state <= TCPS_CLOSING) {
4840 if (ticks - tp->t_rcvtime >= TP_KEEPIDLE(tp) + TP_MAXIDLE(tp))
4841 goto dropit;
4842 /*
4843 * Send a packet designed to force a response if the peer is
4844 * up and reachable: either an ACK if the connection is
4845 * still alive, or an RST if the peer has closed the
4846 * connection due to timeout or reboot. Using sequence
4847 * number tp->snd_una-1 causes the transmitted zero-length
4848 * segment to lie outside the receive window; by the
4849 * protocol spec, this requires the correspondent TCP to
4850 * respond.
4851 */
4852 KMOD_TCPSTAT_INC(tcps_keepprobe);
4853 t_template = tcpip_maketemplate(inp);
4854 if (t_template) {
4855 tcp_respond(tp, t_template->tt_ipgen,
4856 &t_template->tt_t, (struct mbuf *)NULL,
4857 tp->rcv_nxt, tp->snd_una - 1, 0);
4858 free(t_template, M_TEMP);
4859 }
4860 }
4861 bbr_start_hpts_timer(bbr, tp, cts, 4, 0, 0);
4862 return (1);
4863 dropit:
4864 KMOD_TCPSTAT_INC(tcps_keepdrops);
4865 tcp_log_end_status(tp, TCP_EI_STATUS_KEEP_MAX);
4866 return (-ETIMEDOUT); /* tcp_drop() */
4867 }
4868
4869 /*
4870 * Retransmit helper function, clear up all the ack
4871 * flags and take care of important book keeping.
4872 */
4873 static void
4874 bbr_remxt_tmr(struct tcpcb *tp)
4875 {
4876 /*
4877 * The retransmit timer went off, all sack'd blocks must be
4878 * un-acked.
4879 */
4880 struct bbr_sendmap *rsm, *trsm = NULL;
4881 struct tcp_bbr *bbr;
4882 uint32_t cts, lost;
4883
4884 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
4885 cts = tcp_get_usecs(&bbr->rc_tv);
4886 lost = bbr->r_ctl.rc_lost;
4887 if (bbr->r_state && (bbr->r_state != tp->t_state))
4888 bbr_set_state(tp, bbr, 0);
4889
4890 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) {
4891 if (rsm->r_flags & BBR_ACKED) {
4892 uint32_t old_flags;
4893
4894 rsm->r_dupack = 0;
4895 if (rsm->r_in_tmap == 0) {
4896 /* We must re-add it back to the tlist */
4897 if (trsm == NULL) {
4898 TAILQ_INSERT_HEAD(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
4899 } else {
4900 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, trsm, rsm, r_tnext);
4901 }
4902 rsm->r_in_tmap = 1;
4903 }
4904 old_flags = rsm->r_flags;
4905 rsm->r_flags |= BBR_RXT_CLEARED;
4906 rsm->r_flags &= ~(BBR_ACKED | BBR_SACK_PASSED | BBR_WAS_SACKPASS);
4907 bbr_log_type_rsmclear(bbr, cts, rsm, old_flags, __LINE__);
4908 } else {
4909 if ((tp->t_state < TCPS_ESTABLISHED) &&
4910 (rsm->r_start == tp->snd_una)) {
4911 /*
4912 * Special case for TCP FO. Where
4913 * we sent more data beyond the snd_max.
4914 * We don't mark that as lost and stop here.
4915 */
4916 break;
4917 }
4918 if ((rsm->r_flags & BBR_MARKED_LOST) == 0) {
4919 bbr->r_ctl.rc_lost += rsm->r_end - rsm->r_start;
4920 bbr->r_ctl.rc_lost_bytes += rsm->r_end - rsm->r_start;
4921 }
4922 if (bbr_marks_rxt_sack_passed) {
4923 /*
4924 * With this option, we will rack out
4925 * in 1ms increments the rest of the packets.
4926 */
4927 rsm->r_flags |= BBR_SACK_PASSED | BBR_MARKED_LOST;
4928 rsm->r_flags &= ~BBR_WAS_SACKPASS;
4929 } else {
4930 /*
4931 * With this option we only mark them lost
4932 * and remove all sack'd markings. We will run
4933 * another RXT or a TLP. This will cause
4934 * us to eventually send more based on what
4935 * ack's come in.
4936 */
4937 rsm->r_flags |= BBR_MARKED_LOST;
4938 rsm->r_flags &= ~BBR_WAS_SACKPASS;
4939 rsm->r_flags &= ~BBR_SACK_PASSED;
4940 }
4941 }
4942 trsm = rsm;
4943 }
4944 bbr->r_ctl.rc_resend = TAILQ_FIRST(&bbr->r_ctl.rc_map);
4945 /* Clear the count (we just un-acked them) */
4946 bbr_log_to_event(bbr, cts, BBR_TO_FRM_TMR);
4947 bbr->rc_tlp_new_data = 0;
4948 bbr->r_ctl.rc_tlp_seg_send_cnt = 0;
4949 /* zap the behindness on a rxt */
4950 bbr->r_ctl.rc_hptsi_agg_delay = 0;
4951 bbr->r_agg_early_set = 0;
4952 bbr->r_ctl.rc_agg_early = 0;
4953 bbr->rc_tlp_rtx_out = 0;
4954 bbr->r_ctl.rc_sacked = 0;
4955 bbr->r_ctl.rc_sacklast = NULL;
4956 bbr->r_timer_override = 1;
4957 bbr_lt_bw_sampling(bbr, cts, (bbr->r_ctl.rc_lost > lost));
4958 }
4959
4960 /*
4961 * Re-transmit timeout! If we drop the PCB we will return 1, otherwise
4962 * we will setup to retransmit the lowest seq number outstanding.
4963 */
4964 static int
4965 bbr_timeout_rxt(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts)
4966 {
4967 struct inpcb *inp = tptoinpcb(tp);
4968 int32_t rexmt;
4969 int32_t retval = 0;
4970 bool isipv6;
4971
4972 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_RXT;
4973 if (bbr->rc_all_timers_stopped) {
4974 return (1);
4975 }
4976 if (TCPS_HAVEESTABLISHED(tp->t_state) &&
4977 (tp->snd_una == tp->snd_max)) {
4978 /* Nothing outstanding .. nothing to do */
4979 return (0);
4980 }
4981 /*
4982 * Retransmission timer went off. Message has not been acked within
4983 * retransmit interval. Back off to a longer retransmit interval
4984 * and retransmit one segment.
4985 */
4986 if (ctf_progress_timeout_check(tp, true)) {
4987 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__);
4988 return (-ETIMEDOUT); /* tcp_drop() */
4989 }
4990 bbr_remxt_tmr(tp);
4991 if ((bbr->r_ctl.rc_resend == NULL) ||
4992 ((bbr->r_ctl.rc_resend->r_flags & BBR_RWND_COLLAPSED) == 0)) {
4993 /*
4994 * If the rwnd collapsed on
4995 * the one we are retransmitting
4996 * it does not count against the
4997 * rxt count.
4998 */
4999 tp->t_rxtshift++;
5000 }
5001 if (tp->t_rxtshift > TCP_MAXRXTSHIFT) {
5002 tp->t_rxtshift = TCP_MAXRXTSHIFT;
5003 KMOD_TCPSTAT_INC(tcps_timeoutdrop);
5004 tcp_log_end_status(tp, TCP_EI_STATUS_RETRAN);
5005 /* XXXGL: previously t_softerror was casted to uint16_t */
5006 MPASS(tp->t_softerror >= 0);
5007 retval = tp->t_softerror ? -tp->t_softerror : -ETIMEDOUT;
5008 return (retval); /* tcp_drop() */
5009 }
5010 if (tp->t_state == TCPS_SYN_SENT) {
5011 /*
5012 * If the SYN was retransmitted, indicate CWND to be limited
5013 * to 1 segment in cc_conn_init().
5014 */
5015 tp->snd_cwnd = 1;
5016 } else if (tp->t_rxtshift == 1) {
5017 /*
5018 * first retransmit; record ssthresh and cwnd so they can be
5019 * recovered if this turns out to be a "bad" retransmit. A
5020 * retransmit is considered "bad" if an ACK for this segment
5021 * is received within RTT/2 interval; the assumption here is
5022 * that the ACK was already in flight. See "On Estimating
5023 * End-to-End Network Path Properties" by Allman and Paxson
5024 * for more details.
5025 */
5026 tp->snd_cwnd = tp->t_maxseg - bbr->rc_last_options;
5027 if (!IN_RECOVERY(tp->t_flags)) {
5028 tp->snd_cwnd_prev = tp->snd_cwnd;
5029 tp->snd_ssthresh_prev = tp->snd_ssthresh;
5030 tp->snd_recover_prev = tp->snd_recover;
5031 tp->t_badrxtwin = ticks + (tp->t_srtt >> (TCP_RTT_SHIFT + 1));
5032 tp->t_flags |= TF_PREVVALID;
5033 } else {
5034 tp->t_flags &= ~TF_PREVVALID;
5035 }
5036 tp->snd_cwnd = tp->t_maxseg - bbr->rc_last_options;
5037 } else {
5038 tp->snd_cwnd = tp->t_maxseg - bbr->rc_last_options;
5039 tp->t_flags &= ~TF_PREVVALID;
5040 }
5041 KMOD_TCPSTAT_INC(tcps_rexmttimeo);
5042 if ((tp->t_state == TCPS_SYN_SENT) ||
5043 (tp->t_state == TCPS_SYN_RECEIVED))
5044 rexmt = USEC_2_TICKS(BBR_INITIAL_RTO) * tcp_backoff[tp->t_rxtshift];
5045 else
5046 rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift];
5047 TCPT_RANGESET(tp->t_rxtcur, rexmt,
5048 MSEC_2_TICKS(bbr->r_ctl.rc_min_rto_ms),
5049 MSEC_2_TICKS(((uint32_t)bbr->rc_max_rto_sec) * 1000));
5050 /*
5051 * We enter the path for PLMTUD if connection is established or, if
5052 * connection is FIN_WAIT_1 status, reason for the last is that if
5053 * amount of data we send is very small, we could send it in couple
5054 * of packets and process straight to FIN. In that case we won't
5055 * catch ESTABLISHED state.
5056 */
5057 #ifdef INET6
5058 isipv6 = (inp->inp_vflag & INP_IPV6) ? true : false;
5059 #else
5060 isipv6 = false;
5061 #endif
5062 if (((V_tcp_pmtud_blackhole_detect == 1) ||
5063 (V_tcp_pmtud_blackhole_detect == 2 && !isipv6) ||
5064 (V_tcp_pmtud_blackhole_detect == 3 && isipv6)) &&
5065 ((tp->t_state == TCPS_ESTABLISHED) ||
5066 (tp->t_state == TCPS_FIN_WAIT_1))) {
5067 /*
5068 * Idea here is that at each stage of mtu probe (usually,
5069 * 1448 -> 1188 -> 524) should be given 2 chances to recover
5070 * before further clamping down. 'tp->t_rxtshift % 2 == 0'
5071 * should take care of that.
5072 */
5073 if (((tp->t_flags2 & (TF2_PLPMTU_PMTUD | TF2_PLPMTU_MAXSEGSNT)) ==
5074 (TF2_PLPMTU_PMTUD | TF2_PLPMTU_MAXSEGSNT)) &&
5075 (tp->t_rxtshift >= 2 && tp->t_rxtshift < 6 &&
5076 tp->t_rxtshift % 2 == 0)) {
5077 /*
5078 * Enter Path MTU Black-hole Detection mechanism: -
5079 * Disable Path MTU Discovery (IP "DF" bit). -
5080 * Reduce MTU to lower value than what we negotiated
5081 * with peer.
5082 */
5083 if ((tp->t_flags2 & TF2_PLPMTU_BLACKHOLE) == 0) {
5084 /*
5085 * Record that we may have found a black
5086 * hole.
5087 */
5088 tp->t_flags2 |= TF2_PLPMTU_BLACKHOLE;
5089 /* Keep track of previous MSS. */
5090 tp->t_pmtud_saved_maxseg = tp->t_maxseg;
5091 }
5092 /*
5093 * Reduce the MSS to blackhole value or to the
5094 * default in an attempt to retransmit.
5095 */
5096 #ifdef INET6
5097 isipv6 = bbr->r_is_v6;
5098 if (isipv6 &&
5099 tp->t_maxseg > V_tcp_v6pmtud_blackhole_mss) {
5100 /* Use the sysctl tuneable blackhole MSS. */
5101 tp->t_maxseg = V_tcp_v6pmtud_blackhole_mss;
5102 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated);
5103 } else if (isipv6) {
5104 /* Use the default MSS. */
5105 tp->t_maxseg = V_tcp_v6mssdflt;
5106 /*
5107 * Disable Path MTU Discovery when we switch
5108 * to minmss.
5109 */
5110 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD;
5111 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated_min_mss);
5112 }
5113 #endif
5114 #if defined(INET6) && defined(INET)
5115 else
5116 #endif
5117 #ifdef INET
5118 if (tp->t_maxseg > V_tcp_pmtud_blackhole_mss) {
5119 /* Use the sysctl tuneable blackhole MSS. */
5120 tp->t_maxseg = V_tcp_pmtud_blackhole_mss;
5121 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated);
5122 } else {
5123 /* Use the default MSS. */
5124 tp->t_maxseg = V_tcp_mssdflt;
5125 /*
5126 * Disable Path MTU Discovery when we switch
5127 * to minmss.
5128 */
5129 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD;
5130 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_activated_min_mss);
5131 }
5132 #endif
5133 } else {
5134 /*
5135 * If further retransmissions are still unsuccessful
5136 * with a lowered MTU, maybe this isn't a blackhole
5137 * and we restore the previous MSS and blackhole
5138 * detection flags. The limit '6' is determined by
5139 * giving each probe stage (1448, 1188, 524) 2
5140 * chances to recover.
5141 */
5142 if ((tp->t_flags2 & TF2_PLPMTU_BLACKHOLE) &&
5143 (tp->t_rxtshift >= 6)) {
5144 tp->t_flags2 |= TF2_PLPMTU_PMTUD;
5145 tp->t_flags2 &= ~TF2_PLPMTU_BLACKHOLE;
5146 tp->t_maxseg = tp->t_pmtud_saved_maxseg;
5147 KMOD_TCPSTAT_INC(tcps_pmtud_blackhole_failed);
5148 }
5149 }
5150 }
5151 /*
5152 * Disable RFC1323 and SACK if we haven't got any response to our
5153 * third SYN to work-around some broken terminal servers (most of
5154 * which have hopefully been retired) that have bad VJ header
5155 * compression code which trashes TCP segments containing
5156 * unknown-to-them TCP options.
5157 */
5158 if (tcp_rexmit_drop_options && (tp->t_state == TCPS_SYN_SENT) &&
5159 (tp->t_rxtshift == 3))
5160 tp->t_flags &= ~(TF_REQ_SCALE | TF_REQ_TSTMP | TF_SACK_PERMIT);
5161 /*
5162 * If we backed off this far, our srtt estimate is probably bogus.
5163 * Clobber it so we'll take the next rtt measurement as our srtt;
5164 * move the current srtt into rttvar to keep the current retransmit
5165 * times until then.
5166 */
5167 if (tp->t_rxtshift > TCP_MAXRXTSHIFT / 4) {
5168 #ifdef INET6
5169 if (bbr->r_is_v6)
5170 in6_losing(inp);
5171 else
5172 #endif
5173 in_losing(inp);
5174 tp->t_rttvar += (tp->t_srtt >> TCP_RTT_SHIFT);
5175 tp->t_srtt = 0;
5176 }
5177 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una);
5178 tp->snd_recover = tp->snd_max;
5179 tp->t_flags |= TF_ACKNOW;
5180 tp->t_rtttime = 0;
5181
5182 return (retval);
5183 }
5184
5185 static int
5186 bbr_process_timers(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, uint8_t hpts_calling)
5187 {
5188 int32_t ret = 0;
5189 int32_t timers = (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK);
5190
5191 if (timers == 0) {
5192 return (0);
5193 }
5194 if (tp->t_state == TCPS_LISTEN) {
5195 /* no timers on listen sockets */
5196 if (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)
5197 return (0);
5198 return (1);
5199 }
5200 if (TSTMP_LT(cts, bbr->r_ctl.rc_timer_exp)) {
5201 uint32_t left;
5202
5203 if (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) {
5204 ret = -1;
5205 bbr_log_to_processing(bbr, cts, ret, 0, hpts_calling);
5206 return (0);
5207 }
5208 if (hpts_calling == 0) {
5209 ret = -2;
5210 bbr_log_to_processing(bbr, cts, ret, 0, hpts_calling);
5211 return (0);
5212 }
5213 /*
5214 * Ok our timer went off early and we are not paced false
5215 * alarm, go back to sleep.
5216 */
5217 left = bbr->r_ctl.rc_timer_exp - cts;
5218 ret = -3;
5219 bbr_log_to_processing(bbr, cts, ret, left, hpts_calling);
5220 tcp_hpts_insert(tptoinpcb(tp), HPTS_USEC_TO_SLOTS(left));
5221 return (1);
5222 }
5223 bbr->rc_tmr_stopped = 0;
5224 bbr->r_ctl.rc_hpts_flags &= ~PACE_TMR_MASK;
5225 if (timers & PACE_TMR_DELACK) {
5226 ret = bbr_timeout_delack(tp, bbr, cts);
5227 } else if (timers & PACE_TMR_PERSIT) {
5228 ret = bbr_timeout_persist(tp, bbr, cts);
5229 } else if (timers & PACE_TMR_RACK) {
5230 bbr->r_ctl.rc_tlp_rxt_last_time = cts;
5231 ret = bbr_timeout_rack(tp, bbr, cts);
5232 } else if (timers & PACE_TMR_TLP) {
5233 bbr->r_ctl.rc_tlp_rxt_last_time = cts;
5234 ret = bbr_timeout_tlp(tp, bbr, cts);
5235 } else if (timers & PACE_TMR_RXT) {
5236 bbr->r_ctl.rc_tlp_rxt_last_time = cts;
5237 ret = bbr_timeout_rxt(tp, bbr, cts);
5238 } else if (timers & PACE_TMR_KEEP) {
5239 ret = bbr_timeout_keepalive(tp, bbr, cts);
5240 }
5241 bbr_log_to_processing(bbr, cts, ret, timers, hpts_calling);
5242 return (ret);
5243 }
5244
5245 static void
5246 bbr_timer_cancel(struct tcp_bbr *bbr, int32_t line, uint32_t cts)
5247 {
5248 if (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK) {
5249 uint8_t hpts_removed = 0;
5250
5251 if (tcp_in_hpts(bbr->rc_inp) &&
5252 (bbr->rc_timer_first == 1)) {
5253 /*
5254 * If we are canceling timer's when we have the
5255 * timer ahead of the output being paced. We also
5256 * must remove ourselves from the hpts.
5257 */
5258 hpts_removed = 1;
5259 tcp_hpts_remove(bbr->rc_inp);
5260 if (bbr->r_ctl.rc_last_delay_val) {
5261 /* Update the last hptsi delay too */
5262 uint32_t time_since_send;
5263
5264 if (TSTMP_GT(cts, bbr->rc_pacer_started))
5265 time_since_send = cts - bbr->rc_pacer_started;
5266 else
5267 time_since_send = 0;
5268 if (bbr->r_ctl.rc_last_delay_val > time_since_send) {
5269 /* Cut down our slot time */
5270 bbr->r_ctl.rc_last_delay_val -= time_since_send;
5271 } else {
5272 bbr->r_ctl.rc_last_delay_val = 0;
5273 }
5274 bbr->rc_pacer_started = cts;
5275 }
5276 }
5277 bbr->rc_timer_first = 0;
5278 bbr_log_to_cancel(bbr, line, cts, hpts_removed);
5279 bbr->rc_tmr_stopped = bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK;
5280 bbr->r_ctl.rc_hpts_flags &= ~(PACE_TMR_MASK);
5281 }
5282 }
5283
5284 static int
5285 bbr_stopall(struct tcpcb *tp)
5286 {
5287 struct tcp_bbr *bbr;
5288
5289 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
5290 bbr->rc_all_timers_stopped = 1;
5291 return (0);
5292 }
5293
5294 static uint32_t
5295 bbr_get_earliest_send_outstanding(struct tcp_bbr *bbr, struct bbr_sendmap *u_rsm, uint32_t cts)
5296 {
5297 struct bbr_sendmap *rsm;
5298
5299 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap);
5300 if ((rsm == NULL) || (u_rsm == rsm))
5301 return (cts);
5302 return(rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)]);
5303 }
5304
5305 static void
5306 bbr_update_rsm(struct tcpcb *tp, struct tcp_bbr *bbr,
5307 struct bbr_sendmap *rsm, uint32_t cts, uint32_t pacing_time)
5308 {
5309 int32_t idx;
5310
5311 rsm->r_rtr_cnt++;
5312 rsm->r_dupack = 0;
5313 if (rsm->r_rtr_cnt > BBR_NUM_OF_RETRANS) {
5314 rsm->r_rtr_cnt = BBR_NUM_OF_RETRANS;
5315 rsm->r_flags |= BBR_OVERMAX;
5316 }
5317 if (rsm->r_flags & BBR_RWND_COLLAPSED) {
5318 /* Take off the collapsed flag at rxt */
5319 rsm->r_flags &= ~BBR_RWND_COLLAPSED;
5320 }
5321 if (rsm->r_flags & BBR_MARKED_LOST) {
5322 /* We have retransmitted, its no longer lost */
5323 rsm->r_flags &= ~BBR_MARKED_LOST;
5324 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start;
5325 }
5326 if (rsm->r_flags & BBR_RXT_CLEARED) {
5327 /*
5328 * We hit a RXT timer on it and
5329 * we cleared the "acked" flag.
5330 * We now have it going back into
5331 * flight, we can remove the cleared
5332 * flag and possibly do accounting on
5333 * this piece.
5334 */
5335 rsm->r_flags &= ~BBR_RXT_CLEARED;
5336 }
5337 if ((rsm->r_rtr_cnt > 1) && ((rsm->r_flags & BBR_TLP) == 0)) {
5338 bbr->r_ctl.rc_holes_rxt += (rsm->r_end - rsm->r_start);
5339 rsm->r_rtr_bytes += (rsm->r_end - rsm->r_start);
5340 }
5341 idx = rsm->r_rtr_cnt - 1;
5342 rsm->r_tim_lastsent[idx] = cts;
5343 rsm->r_pacing_delay = pacing_time;
5344 rsm->r_delivered = bbr->r_ctl.rc_delivered;
5345 rsm->r_ts_valid = bbr->rc_ts_valid;
5346 if (bbr->rc_ts_valid)
5347 rsm->r_del_ack_ts = bbr->r_ctl.last_inbound_ts;
5348 if (bbr->r_ctl.r_app_limited_until)
5349 rsm->r_app_limited = 1;
5350 else
5351 rsm->r_app_limited = 0;
5352 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW)
5353 rsm->r_bbr_state = bbr_state_val(bbr);
5354 else
5355 rsm->r_bbr_state = 8;
5356 if (rsm->r_flags & BBR_ACKED) {
5357 /* Problably MTU discovery messing with us */
5358 uint32_t old_flags;
5359
5360 old_flags = rsm->r_flags;
5361 rsm->r_flags &= ~BBR_ACKED;
5362 bbr_log_type_rsmclear(bbr, cts, rsm, old_flags, __LINE__);
5363 bbr->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start);
5364 if (bbr->r_ctl.rc_sacked == 0)
5365 bbr->r_ctl.rc_sacklast = NULL;
5366 }
5367 if (rsm->r_in_tmap) {
5368 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
5369 }
5370 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
5371 rsm->r_in_tmap = 1;
5372 if (rsm->r_flags & BBR_SACK_PASSED) {
5373 /* We have retransmitted due to the SACK pass */
5374 rsm->r_flags &= ~BBR_SACK_PASSED;
5375 rsm->r_flags |= BBR_WAS_SACKPASS;
5376 }
5377 rsm->r_first_sent_time = bbr_get_earliest_send_outstanding(bbr, rsm, cts);
5378 rsm->r_flight_at_send = ctf_flight_size(bbr->rc_tp,
5379 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
5380 bbr->r_ctl.rc_next = TAILQ_NEXT(rsm, r_next);
5381 if (bbr->r_ctl.rc_bbr_hptsi_gain > BBR_UNIT) {
5382 rsm->r_is_gain = 1;
5383 rsm->r_is_drain = 0;
5384 } else if (bbr->r_ctl.rc_bbr_hptsi_gain < BBR_UNIT) {
5385 rsm->r_is_drain = 1;
5386 rsm->r_is_gain = 0;
5387 } else {
5388 rsm->r_is_drain = 0;
5389 rsm->r_is_gain = 0;
5390 }
5391 rsm->r_del_time = bbr->r_ctl.rc_del_time; /* TEMP GOOGLE CODE */
5392 }
5393
5394 /*
5395 * Returns 0, or the sequence where we stopped
5396 * updating. We also update the lenp to be the amount
5397 * of data left.
5398 */
5399
5400 static uint32_t
5401 bbr_update_entry(struct tcpcb *tp, struct tcp_bbr *bbr,
5402 struct bbr_sendmap *rsm, uint32_t cts, int32_t *lenp, uint32_t pacing_time)
5403 {
5404 /*
5405 * We (re-)transmitted starting at rsm->r_start for some length
5406 * (possibly less than r_end.
5407 */
5408 struct bbr_sendmap *nrsm;
5409 uint32_t c_end;
5410 int32_t len;
5411
5412 len = *lenp;
5413 c_end = rsm->r_start + len;
5414 if (SEQ_GEQ(c_end, rsm->r_end)) {
5415 /*
5416 * We retransmitted the whole piece or more than the whole
5417 * slopping into the next rsm.
5418 */
5419 bbr_update_rsm(tp, bbr, rsm, cts, pacing_time);
5420 if (c_end == rsm->r_end) {
5421 *lenp = 0;
5422 return (0);
5423 } else {
5424 int32_t act_len;
5425
5426 /* Hangs over the end return whats left */
5427 act_len = rsm->r_end - rsm->r_start;
5428 *lenp = (len - act_len);
5429 return (rsm->r_end);
5430 }
5431 /* We don't get out of this block. */
5432 }
5433 /*
5434 * Here we retransmitted less than the whole thing which means we
5435 * have to split this into what was transmitted and what was not.
5436 */
5437 nrsm = bbr_alloc_full_limit(bbr);
5438 if (nrsm == NULL) {
5439 *lenp = 0;
5440 return (0);
5441 }
5442 /*
5443 * So here we are going to take the original rsm and make it what we
5444 * retransmitted. nrsm will be the tail portion we did not
5445 * retransmit. For example say the chunk was 1, 11 (10 bytes). And
5446 * we retransmitted 5 bytes i.e. 1, 5. The original piece shrinks to
5447 * 1, 6 and the new piece will be 6, 11.
5448 */
5449 bbr_clone_rsm(bbr, nrsm, rsm, c_end);
5450 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next);
5451 nrsm->r_dupack = 0;
5452 if (rsm->r_in_tmap) {
5453 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext);
5454 nrsm->r_in_tmap = 1;
5455 }
5456 rsm->r_flags &= (~BBR_HAS_FIN);
5457 bbr_update_rsm(tp, bbr, rsm, cts, pacing_time);
5458 *lenp = 0;
5459 return (0);
5460 }
5461
5462 static uint64_t
5463 bbr_get_hardware_rate(struct tcp_bbr *bbr)
5464 {
5465 uint64_t bw;
5466
5467 bw = bbr_get_bw(bbr);
5468 bw *= (uint64_t)bbr_hptsi_gain[BBR_SUB_GAIN];
5469 bw /= (uint64_t)BBR_UNIT;
5470 return(bw);
5471 }
5472
5473 static void
5474 bbr_setup_less_of_rate(struct tcp_bbr *bbr, uint32_t cts,
5475 uint64_t act_rate, uint64_t rate_wanted)
5476 {
5477 /*
5478 * We could not get a full gains worth
5479 * of rate.
5480 */
5481 if (get_filter_value(&bbr->r_ctl.rc_delrate) >= act_rate) {
5482 /* we can't even get the real rate */
5483 uint64_t red;
5484
5485 bbr->skip_gain = 1;
5486 bbr->gain_is_limited = 0;
5487 red = get_filter_value(&bbr->r_ctl.rc_delrate) - act_rate;
5488 if (red)
5489 filter_reduce_by(&bbr->r_ctl.rc_delrate, red, cts);
5490 } else {
5491 /* We can use a lower gain */
5492 bbr->skip_gain = 0;
5493 bbr->gain_is_limited = 1;
5494 }
5495 }
5496
5497 static void
5498 bbr_update_hardware_pacing_rate(struct tcp_bbr *bbr, uint32_t cts)
5499 {
5500 const struct tcp_hwrate_limit_table *nrte;
5501 int error, rate = -1;
5502
5503 if (bbr->r_ctl.crte == NULL)
5504 return;
5505 if ((bbr->rc_inp->inp_route.ro_nh == NULL) ||
5506 (bbr->rc_inp->inp_route.ro_nh->nh_ifp == NULL)) {
5507 /* Lost our routes? */
5508 /* Clear the way for a re-attempt */
5509 bbr->bbr_attempt_hdwr_pace = 0;
5510 lost_rate:
5511 bbr->gain_is_limited = 0;
5512 bbr->skip_gain = 0;
5513 bbr->bbr_hdrw_pacing = 0;
5514 counter_u64_add(bbr_flows_whdwr_pacing, -1);
5515 counter_u64_add(bbr_flows_nohdwr_pacing, 1);
5516 tcp_bbr_tso_size_check(bbr, cts);
5517 return;
5518 }
5519 rate = bbr_get_hardware_rate(bbr);
5520 nrte = tcp_chg_pacing_rate(bbr->r_ctl.crte,
5521 bbr->rc_tp,
5522 bbr->rc_inp->inp_route.ro_nh->nh_ifp,
5523 rate,
5524 (RS_PACING_GEQ|RS_PACING_SUB_OK),
5525 &error, NULL);
5526 if (nrte == NULL) {
5527 goto lost_rate;
5528 }
5529 if (nrte != bbr->r_ctl.crte) {
5530 bbr->r_ctl.crte = nrte;
5531 if (error == 0) {
5532 BBR_STAT_INC(bbr_hdwr_rl_mod_ok);
5533 if (bbr->r_ctl.crte->rate < rate) {
5534 /* We have a problem */
5535 bbr_setup_less_of_rate(bbr, cts,
5536 bbr->r_ctl.crte->rate, rate);
5537 } else {
5538 /* We are good */
5539 bbr->gain_is_limited = 0;
5540 bbr->skip_gain = 0;
5541 }
5542 } else {
5543 /* A failure should release the tag */
5544 BBR_STAT_INC(bbr_hdwr_rl_mod_fail);
5545 bbr->gain_is_limited = 0;
5546 bbr->skip_gain = 0;
5547 bbr->bbr_hdrw_pacing = 0;
5548 }
5549 bbr_type_log_hdwr_pacing(bbr,
5550 bbr->r_ctl.crte->ptbl->rs_ifp,
5551 rate,
5552 ((bbr->r_ctl.crte == NULL) ? 0 : bbr->r_ctl.crte->rate),
5553 __LINE__,
5554 cts,
5555 error);
5556 }
5557 }
5558
5559 static void
5560 bbr_adjust_for_hw_pacing(struct tcp_bbr *bbr, uint32_t cts)
5561 {
5562 /*
5563 * If we have hardware pacing support
5564 * we need to factor that in for our
5565 * TSO size.
5566 */
5567 const struct tcp_hwrate_limit_table *rlp;
5568 uint32_t cur_delay, seg_sz, maxseg, new_tso, delta, hdwr_delay;
5569
5570 if ((bbr->bbr_hdrw_pacing == 0) ||
5571 (IN_RECOVERY(bbr->rc_tp->t_flags)) ||
5572 (bbr->r_ctl.crte == NULL))
5573 return;
5574 if (bbr->hw_pacing_set == 0) {
5575 /* Not yet by the hdwr pacing count delay */
5576 return;
5577 }
5578 if (bbr_hdwr_pace_adjust == 0) {
5579 /* No adjustment */
5580 return;
5581 }
5582 rlp = bbr->r_ctl.crte;
5583 if (bbr->rc_tp->t_maxseg > bbr->rc_last_options)
5584 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options;
5585 else
5586 maxseg = BBR_MIN_SEG - bbr->rc_last_options;
5587 /*
5588 * So lets first get the
5589 * time we will take between
5590 * TSO sized sends currently without
5591 * hardware help.
5592 */
5593 cur_delay = bbr_get_pacing_delay(bbr, BBR_UNIT,
5594 bbr->r_ctl.rc_pace_max_segs, cts, 1);
5595 hdwr_delay = bbr->r_ctl.rc_pace_max_segs / maxseg;
5596 hdwr_delay *= rlp->time_between;
5597 if (cur_delay > hdwr_delay)
5598 delta = cur_delay - hdwr_delay;
5599 else
5600 delta = 0;
5601 bbr_log_type_tsosize(bbr, cts, delta, cur_delay, hdwr_delay,
5602 (bbr->r_ctl.rc_pace_max_segs / maxseg),
5603 1);
5604 if (delta &&
5605 (delta < (max(rlp->time_between,
5606 bbr->r_ctl.bbr_hptsi_segments_delay_tar)))) {
5607 /*
5608 * Now lets divide by the pacing
5609 * time between each segment the
5610 * hardware sends rounding up and
5611 * derive a bytes from that. We multiply
5612 * that by bbr_hdwr_pace_adjust to get
5613 * more bang for our buck.
5614 *
5615 * The goal is to have the software pacer
5616 * waiting no more than an additional
5617 * pacing delay if we can (without the
5618 * compensation i.e. x bbr_hdwr_pace_adjust).
5619 */
5620 seg_sz = max(((cur_delay + rlp->time_between)/rlp->time_between),
5621 (bbr->r_ctl.rc_pace_max_segs/maxseg));
5622 seg_sz *= bbr_hdwr_pace_adjust;
5623 if (bbr_hdwr_pace_floor &&
5624 (seg_sz < bbr->r_ctl.crte->ptbl->rs_min_seg)) {
5625 /* Currently hardware paces
5626 * out rs_min_seg segments at a time.
5627 * We need to make sure we always send at least
5628 * a full burst of bbr_hdwr_pace_floor down.
5629 */
5630 seg_sz = bbr->r_ctl.crte->ptbl->rs_min_seg;
5631 }
5632 seg_sz *= maxseg;
5633 } else if (delta == 0) {
5634 /*
5635 * The highest pacing rate is
5636 * above our b/w gained. This means
5637 * we probably are going quite fast at
5638 * the hardware highest rate. Lets just multiply
5639 * the calculated TSO size by the
5640 * multiplier factor (its probably
5641 * 4 segments in the default config for
5642 * mlx).
5643 */
5644 seg_sz = bbr->r_ctl.rc_pace_max_segs * bbr_hdwr_pace_adjust;
5645 if (bbr_hdwr_pace_floor &&
5646 (seg_sz < bbr->r_ctl.crte->ptbl->rs_min_seg)) {
5647 /* Currently hardware paces
5648 * out rs_min_seg segments at a time.
5649 * We need to make sure we always send at least
5650 * a full burst of bbr_hdwr_pace_floor down.
5651 */
5652 seg_sz = bbr->r_ctl.crte->ptbl->rs_min_seg;
5653 }
5654 } else {
5655 /*
5656 * The pacing time difference is so
5657 * big that the hardware will
5658 * pace out more rapidly then we
5659 * really want and then we
5660 * will have a long delay. Lets just keep
5661 * the same TSO size so its as if
5662 * we were not using hdwr pacing (we
5663 * just gain a bit of spacing from the
5664 * hardware if seg_sz > 1).
5665 */
5666 seg_sz = bbr->r_ctl.rc_pace_max_segs;
5667 }
5668 if (seg_sz > bbr->r_ctl.rc_pace_max_segs)
5669 new_tso = seg_sz;
5670 else
5671 new_tso = bbr->r_ctl.rc_pace_max_segs;
5672 if (new_tso >= (PACE_MAX_IP_BYTES-maxseg))
5673 new_tso = PACE_MAX_IP_BYTES - maxseg;
5674
5675 if (new_tso != bbr->r_ctl.rc_pace_max_segs) {
5676 bbr_log_type_tsosize(bbr, cts, new_tso, 0, bbr->r_ctl.rc_pace_max_segs, maxseg, 0);
5677 bbr->r_ctl.rc_pace_max_segs = new_tso;
5678 }
5679 }
5680
5681 static void
5682 tcp_bbr_tso_size_check(struct tcp_bbr *bbr, uint32_t cts)
5683 {
5684 uint64_t bw;
5685 uint32_t old_tso = 0, new_tso;
5686 uint32_t maxseg, bytes;
5687 uint32_t tls_seg=0;
5688 /*
5689 * Google/linux uses the following algorithm to determine
5690 * the TSO size based on the b/w of the link (from Neal Cardwell email 9/27/18):
5691 *
5692 * bytes = bw_in_bytes_per_second / 1000
5693 * bytes = min(bytes, 64k)
5694 * tso_segs = bytes / MSS
5695 * if (bw < 1.2Mbs)
5696 * min_tso_segs = 1
5697 * else
5698 * min_tso_segs = 2
5699 * tso_segs = max(tso_segs, min_tso_segs)
5700 *
5701 * * Note apply a device specific limit (we apply this in the
5702 * tcp_m_copym).
5703 * Note that before the initial measurement is made google bursts out
5704 * a full iwnd just like new-reno/cubic.
5705 *
5706 * We do not use this algorithm. Instead we
5707 * use a two phased approach:
5708 *
5709 * if ( bw <= per-tcb-cross-over)
5710 * goal_tso = calculate how much with this bw we
5711 * can send in goal-time seconds.
5712 * if (goal_tso > mss)
5713 * seg = goal_tso / mss
5714 * tso = seg * mss
5715 * else
5716 * tso = mss
5717 * if (tso > per-tcb-max)
5718 * tso = per-tcb-max
5719 * else if ( bw > 512Mbps)
5720 * tso = max-tso (64k/mss)
5721 * else
5722 * goal_tso = bw / per-tcb-divsor
5723 * seg = (goal_tso + mss-1)/mss
5724 * tso = seg * mss
5725 *
5726 * if (tso < per-tcb-floor)
5727 * tso = per-tcb-floor
5728 * if (tso > per-tcb-utter_max)
5729 * tso = per-tcb-utter_max
5730 *
5731 * Note the default per-tcb-divisor is 1000 (same as google).
5732 * the goal cross over is 30Mbps however. To recreate googles
5733 * algorithm you need to set:
5734 *
5735 * cross-over = 23,168,000 bps
5736 * goal-time = 18000
5737 * per-tcb-max = 2
5738 * per-tcb-divisor = 1000
5739 * per-tcb-floor = 1
5740 *
5741 * This will get you "google bbr" behavior with respect to tso size.
5742 *
5743 * Note we do set anything TSO size until we are past the initial
5744 * window. Before that we gnerally use either a single MSS
5745 * or we use the full IW size (so we burst a IW at a time)
5746 */
5747
5748 if (bbr->rc_tp->t_maxseg > bbr->rc_last_options) {
5749 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options;
5750 } else {
5751 maxseg = BBR_MIN_SEG - bbr->rc_last_options;
5752 }
5753 old_tso = bbr->r_ctl.rc_pace_max_segs;
5754 if (bbr->rc_past_init_win == 0) {
5755 /*
5756 * Not enough data has been acknowledged to make a
5757 * judgement. Set up the initial TSO based on if we
5758 * are sending a full IW at once or not.
5759 */
5760 if (bbr->rc_use_google)
5761 bbr->r_ctl.rc_pace_max_segs = ((bbr->rc_tp->t_maxseg - bbr->rc_last_options) * 2);
5762 else if (bbr->bbr_init_win_cheat)
5763 bbr->r_ctl.rc_pace_max_segs = bbr_initial_cwnd(bbr, bbr->rc_tp);
5764 else
5765 bbr->r_ctl.rc_pace_max_segs = bbr->rc_tp->t_maxseg - bbr->rc_last_options;
5766 if (bbr->r_ctl.rc_pace_min_segs != bbr->rc_tp->t_maxseg)
5767 bbr->r_ctl.rc_pace_min_segs = bbr->rc_tp->t_maxseg;
5768 if (bbr->r_ctl.rc_pace_max_segs == 0) {
5769 bbr->r_ctl.rc_pace_max_segs = maxseg;
5770 }
5771 bbr_log_type_tsosize(bbr, cts, bbr->r_ctl.rc_pace_max_segs, tls_seg, old_tso, maxseg, 0);
5772 bbr_adjust_for_hw_pacing(bbr, cts);
5773 return;
5774 }
5775 /**
5776 * Now lets set the TSO goal based on our delivery rate in
5777 * bytes per second. Note we only do this if
5778 * we have acked at least the initial cwnd worth of data.
5779 */
5780 bw = bbr_get_bw(bbr);
5781 if (IN_RECOVERY(bbr->rc_tp->t_flags) &&
5782 (bbr->rc_use_google == 0)) {
5783 /* We clamp to one MSS in recovery */
5784 new_tso = maxseg;
5785 } else if (bbr->rc_use_google) {
5786 int min_tso_segs;
5787
5788 /* Google considers the gain too */
5789 if (bbr->r_ctl.rc_bbr_hptsi_gain != BBR_UNIT) {
5790 bw *= bbr->r_ctl.rc_bbr_hptsi_gain;
5791 bw /= BBR_UNIT;
5792 }
5793 bytes = bw / 1024;
5794 if (bytes > (64 * 1024))
5795 bytes = 64 * 1024;
5796 new_tso = bytes / maxseg;
5797 if (bw < ONE_POINT_TWO_MEG)
5798 min_tso_segs = 1;
5799 else
5800 min_tso_segs = 2;
5801 if (new_tso < min_tso_segs)
5802 new_tso = min_tso_segs;
5803 new_tso *= maxseg;
5804 } else if (bbr->rc_no_pacing) {
5805 new_tso = (PACE_MAX_IP_BYTES / maxseg) * maxseg;
5806 } else if (bw <= bbr->r_ctl.bbr_cross_over) {
5807 /*
5808 * Calculate the worse case b/w TSO if we are inserting no
5809 * more than a delay_target number of TSO's.
5810 */
5811 uint32_t tso_len, min_tso;
5812
5813 tso_len = bbr_get_pacing_length(bbr, BBR_UNIT, bbr->r_ctl.bbr_hptsi_segments_delay_tar, bw);
5814 if (tso_len > maxseg) {
5815 new_tso = tso_len / maxseg;
5816 if (new_tso > bbr->r_ctl.bbr_hptsi_segments_max)
5817 new_tso = bbr->r_ctl.bbr_hptsi_segments_max;
5818 new_tso *= maxseg;
5819 } else {
5820 /*
5821 * less than a full sized frame yikes.. long rtt or
5822 * low bw?
5823 */
5824 min_tso = bbr_minseg(bbr);
5825 if ((tso_len > min_tso) && (bbr_all_get_min == 0))
5826 new_tso = rounddown(tso_len, min_tso);
5827 else
5828 new_tso = min_tso;
5829 }
5830 } else if (bw > FIVETWELVE_MBPS) {
5831 /*
5832 * This guy is so fast b/w wise that we can TSO as large as
5833 * possible of segments that the NIC will allow.
5834 */
5835 new_tso = rounddown(PACE_MAX_IP_BYTES, maxseg);
5836 } else {
5837 /*
5838 * This formula is based on attempting to send a segment or
5839 * more every bbr_hptsi_per_second. The default is 1000
5840 * which means you are targeting what you can send every 1ms
5841 * based on the peers bw.
5842 *
5843 * If the number drops to say 500, then you are looking more
5844 * at 2ms and you will raise how much we send in a single
5845 * TSO thus saving CPU (less bbr_output_wtime() calls). The
5846 * trade off of course is you will send more at once and
5847 * thus tend to clump up the sends into larger "bursts"
5848 * building a queue.
5849 */
5850 bw /= bbr->r_ctl.bbr_hptsi_per_second;
5851 new_tso = roundup(bw, (uint64_t)maxseg);
5852 /*
5853 * Gate the floor to match what our lower than 48Mbps
5854 * algorithm does. The ceiling (bbr_hptsi_segments_max) thus
5855 * becomes the floor for this calculation.
5856 */
5857 if (new_tso < (bbr->r_ctl.bbr_hptsi_segments_max * maxseg))
5858 new_tso = (bbr->r_ctl.bbr_hptsi_segments_max * maxseg);
5859 }
5860 if (bbr->r_ctl.bbr_hptsi_segments_floor && (new_tso < (maxseg * bbr->r_ctl.bbr_hptsi_segments_floor)))
5861 new_tso = maxseg * bbr->r_ctl.bbr_hptsi_segments_floor;
5862 if (new_tso > PACE_MAX_IP_BYTES)
5863 new_tso = rounddown(PACE_MAX_IP_BYTES, maxseg);
5864 /* Enforce an utter maximum. */
5865 if (bbr->r_ctl.bbr_utter_max && (new_tso > (bbr->r_ctl.bbr_utter_max * maxseg))) {
5866 new_tso = bbr->r_ctl.bbr_utter_max * maxseg;
5867 }
5868 if (old_tso != new_tso) {
5869 /* Only log changes */
5870 bbr_log_type_tsosize(bbr, cts, new_tso, tls_seg, old_tso, maxseg, 0);
5871 bbr->r_ctl.rc_pace_max_segs = new_tso;
5872 }
5873 /* We have hardware pacing! */
5874 bbr_adjust_for_hw_pacing(bbr, cts);
5875 }
5876
5877 static void
5878 bbr_log_output(struct tcp_bbr *bbr, struct tcpcb *tp, struct tcpopt *to, int32_t len,
5879 uint32_t seq_out, uint16_t th_flags, int32_t err, uint32_t cts,
5880 struct mbuf *mb, int32_t * abandon, struct bbr_sendmap *hintrsm, uint32_t delay_calc,
5881 struct sockbuf *sb)
5882 {
5883
5884 struct bbr_sendmap *rsm, *nrsm;
5885 register uint32_t snd_max, snd_una;
5886 uint32_t pacing_time;
5887 /*
5888 * Add to the RACK log of packets in flight or retransmitted. If
5889 * there is a TS option we will use the TS echoed, if not we will
5890 * grab a TS.
5891 *
5892 * Retransmissions will increment the count and move the ts to its
5893 * proper place. Note that if options do not include TS's then we
5894 * won't be able to effectively use the ACK for an RTT on a retran.
5895 *
5896 * Notes about r_start and r_end. Lets consider a send starting at
5897 * sequence 1 for 10 bytes. In such an example the r_start would be
5898 * 1 (starting sequence) but the r_end would be r_start+len i.e. 11.
5899 * This means that r_end is actually the first sequence for the next
5900 * slot (11).
5901 *
5902 */
5903 INP_WLOCK_ASSERT(tptoinpcb(tp));
5904 if (err) {
5905 /*
5906 * We don't log errors -- we could but snd_max does not
5907 * advance in this case either.
5908 */
5909 return;
5910 }
5911 if (th_flags & TH_RST) {
5912 /*
5913 * We don't log resets and we return immediately from
5914 * sending
5915 */
5916 *abandon = 1;
5917 return;
5918 }
5919 snd_una = tp->snd_una;
5920 if (th_flags & (TH_SYN | TH_FIN) && (hintrsm == NULL)) {
5921 /*
5922 * The call to bbr_log_output is made before bumping
5923 * snd_max. This means we can record one extra byte on a SYN
5924 * or FIN if seq_out is adding more on and a FIN is present
5925 * (and we are not resending).
5926 */
5927 if ((th_flags & TH_SYN) && (tp->iss == seq_out))
5928 len++;
5929 if (th_flags & TH_FIN)
5930 len++;
5931 }
5932 if (SEQ_LEQ((seq_out + len), snd_una)) {
5933 /* Are sending an old segment to induce an ack (keep-alive)? */
5934 return;
5935 }
5936 if (SEQ_LT(seq_out, snd_una)) {
5937 /* huh? should we panic? */
5938 uint32_t end;
5939
5940 end = seq_out + len;
5941 seq_out = snd_una;
5942 len = end - seq_out;
5943 }
5944 snd_max = tp->snd_max;
5945 if (len == 0) {
5946 /* We don't log zero window probes */
5947 return;
5948 }
5949 pacing_time = bbr_get_pacing_delay(bbr, bbr->r_ctl.rc_bbr_hptsi_gain, len, cts, 1);
5950 /* First question is it a retransmission? */
5951 if (seq_out == snd_max) {
5952 again:
5953 rsm = bbr_alloc(bbr);
5954 if (rsm == NULL) {
5955 return;
5956 }
5957 rsm->r_flags = 0;
5958 if (th_flags & TH_SYN)
5959 rsm->r_flags |= BBR_HAS_SYN;
5960 if (th_flags & TH_FIN)
5961 rsm->r_flags |= BBR_HAS_FIN;
5962 rsm->r_tim_lastsent[0] = cts;
5963 rsm->r_rtr_cnt = 1;
5964 rsm->r_rtr_bytes = 0;
5965 rsm->r_start = seq_out;
5966 rsm->r_end = rsm->r_start + len;
5967 rsm->r_dupack = 0;
5968 rsm->r_delivered = bbr->r_ctl.rc_delivered;
5969 rsm->r_pacing_delay = pacing_time;
5970 rsm->r_ts_valid = bbr->rc_ts_valid;
5971 if (bbr->rc_ts_valid)
5972 rsm->r_del_ack_ts = bbr->r_ctl.last_inbound_ts;
5973 rsm->r_del_time = bbr->r_ctl.rc_del_time;
5974 if (bbr->r_ctl.r_app_limited_until)
5975 rsm->r_app_limited = 1;
5976 else
5977 rsm->r_app_limited = 0;
5978 rsm->r_first_sent_time = bbr_get_earliest_send_outstanding(bbr, rsm, cts);
5979 rsm->r_flight_at_send = ctf_flight_size(bbr->rc_tp,
5980 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
5981 /*
5982 * Here we must also add in this rsm since snd_max
5983 * is updated after we return from a new send.
5984 */
5985 rsm->r_flight_at_send += len;
5986 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_map, rsm, r_next);
5987 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
5988 rsm->r_in_tmap = 1;
5989 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW)
5990 rsm->r_bbr_state = bbr_state_val(bbr);
5991 else
5992 rsm->r_bbr_state = 8;
5993 if (bbr->r_ctl.rc_bbr_hptsi_gain > BBR_UNIT) {
5994 rsm->r_is_gain = 1;
5995 rsm->r_is_drain = 0;
5996 } else if (bbr->r_ctl.rc_bbr_hptsi_gain < BBR_UNIT) {
5997 rsm->r_is_drain = 1;
5998 rsm->r_is_gain = 0;
5999 } else {
6000 rsm->r_is_drain = 0;
6001 rsm->r_is_gain = 0;
6002 }
6003 return;
6004 }
6005 /*
6006 * If we reach here its a retransmission and we need to find it.
6007 */
6008 more:
6009 if (hintrsm && (hintrsm->r_start == seq_out)) {
6010 rsm = hintrsm;
6011 hintrsm = NULL;
6012 } else if (bbr->r_ctl.rc_next) {
6013 /* We have a hint from a previous run */
6014 rsm = bbr->r_ctl.rc_next;
6015 } else {
6016 /* No hints sorry */
6017 rsm = NULL;
6018 }
6019 if ((rsm) && (rsm->r_start == seq_out)) {
6020 /*
6021 * We used rc_next or hintrsm to retransmit, hopefully the
6022 * likely case.
6023 */
6024 seq_out = bbr_update_entry(tp, bbr, rsm, cts, &len, pacing_time);
6025 if (len == 0) {
6026 return;
6027 } else {
6028 goto more;
6029 }
6030 }
6031 /* Ok it was not the last pointer go through it the hard way. */
6032 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) {
6033 if (rsm->r_start == seq_out) {
6034 seq_out = bbr_update_entry(tp, bbr, rsm, cts, &len, pacing_time);
6035 bbr->r_ctl.rc_next = TAILQ_NEXT(rsm, r_next);
6036 if (len == 0) {
6037 return;
6038 } else {
6039 continue;
6040 }
6041 }
6042 if (SEQ_GEQ(seq_out, rsm->r_start) && SEQ_LT(seq_out, rsm->r_end)) {
6043 /* Transmitted within this piece */
6044 /*
6045 * Ok we must split off the front and then let the
6046 * update do the rest
6047 */
6048 nrsm = bbr_alloc_full_limit(bbr);
6049 if (nrsm == NULL) {
6050 bbr_update_rsm(tp, bbr, rsm, cts, pacing_time);
6051 return;
6052 }
6053 /*
6054 * copy rsm to nrsm and then trim the front of rsm
6055 * to not include this part.
6056 */
6057 bbr_clone_rsm(bbr, nrsm, rsm, seq_out);
6058 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next);
6059 if (rsm->r_in_tmap) {
6060 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext);
6061 nrsm->r_in_tmap = 1;
6062 }
6063 rsm->r_flags &= (~BBR_HAS_FIN);
6064 seq_out = bbr_update_entry(tp, bbr, nrsm, cts, &len, pacing_time);
6065 if (len == 0) {
6066 return;
6067 }
6068 }
6069 }
6070 /*
6071 * Hmm not found in map did they retransmit both old and on into the
6072 * new?
6073 */
6074 if (seq_out == tp->snd_max) {
6075 goto again;
6076 } else if (SEQ_LT(seq_out, tp->snd_max)) {
6077 #ifdef BBR_INVARIANTS
6078 printf("seq_out:%u len:%d snd_una:%u snd_max:%u -- but rsm not found?\n",
6079 seq_out, len, tp->snd_una, tp->snd_max);
6080 printf("Starting Dump of all rack entries\n");
6081 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) {
6082 printf("rsm:%p start:%u end:%u\n",
6083 rsm, rsm->r_start, rsm->r_end);
6084 }
6085 printf("Dump complete\n");
6086 panic("seq_out not found rack:%p tp:%p",
6087 bbr, tp);
6088 #endif
6089 } else {
6090 #ifdef BBR_INVARIANTS
6091 /*
6092 * Hmm beyond sndmax? (only if we are using the new rtt-pack
6093 * flag)
6094 */
6095 panic("seq_out:%u(%d) is beyond snd_max:%u tp:%p",
6096 seq_out, len, tp->snd_max, tp);
6097 #endif
6098 }
6099 }
6100
6101 static void
6102 bbr_collapse_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, int32_t rtt)
6103 {
6104 /*
6105 * Collapse timeout back the cum-ack moved.
6106 */
6107 tp->t_rxtshift = 0;
6108 tp->t_softerror = 0;
6109 }
6110
6111 static void
6112 tcp_bbr_xmit_timer(struct tcp_bbr *bbr, uint32_t rtt_usecs, uint32_t rsm_send_time, uint32_t r_start, uint32_t tsin)
6113 {
6114 bbr->rtt_valid = 1;
6115 bbr->r_ctl.cur_rtt = rtt_usecs;
6116 bbr->r_ctl.ts_in = tsin;
6117 if (rsm_send_time)
6118 bbr->r_ctl.cur_rtt_send_time = rsm_send_time;
6119 }
6120
6121 static void
6122 bbr_make_timestamp_determination(struct tcp_bbr *bbr)
6123 {
6124 /**
6125 * We have in our bbr control:
6126 * 1) The timestamp we started observing cum-acks (bbr->r_ctl.bbr_ts_check_tstmp).
6127 * 2) Our timestamp indicating when we sent that packet (bbr->r_ctl.rsm->bbr_ts_check_our_cts).
6128 * 3) The current timestamp that just came in (bbr->r_ctl.last_inbound_ts)
6129 * 4) The time that the packet that generated that ack was sent (bbr->r_ctl.cur_rtt_send_time)
6130 *
6131 * Now we can calculate the time between the sends by doing:
6132 *
6133 * delta = bbr->r_ctl.cur_rtt_send_time - bbr->r_ctl.bbr_ts_check_our_cts
6134 *
6135 * And the peer's time between receiving them by doing:
6136 *
6137 * peer_delta = bbr->r_ctl.last_inbound_ts - bbr->r_ctl.bbr_ts_check_tstmp
6138 *
6139 * We want to figure out if the timestamp values are in msec, 10msec or usec.
6140 * We also may find that we can't use the timestamps if say we see
6141 * that the peer_delta indicates that though we may have taken 10ms to
6142 * pace out the data, it only saw 1ms between the two packets. This would
6143 * indicate that somewhere on the path is a batching entity that is giving
6144 * out time-slices of the actual b/w. This would mean we could not use
6145 * reliably the peers timestamps.
6146 *
6147 * We expect delta > peer_delta initially. Until we figure out the
6148 * timestamp difference which we will store in bbr->r_ctl.bbr_peer_tsratio.
6149 * If we place 1000 there then its a ms vs our usec. If we place 10000 there
6150 * then its 10ms vs our usec. If the peer is running a usec clock we would
6151 * put a 1 there. If the value is faster then ours, we will disable the
6152 * use of timestamps (though we could revist this later if we find it to be not
6153 * just an isolated one or two flows)).
6154 *
6155 * To detect the batching middle boxes we will come up with our compensation and
6156 * if with it in place, we find the peer is drastically off (by some margin) in
6157 * the smaller direction, then we will assume the worst case and disable use of timestamps.
6158 *
6159 */
6160 uint64_t delta, peer_delta, delta_up;
6161
6162 delta = bbr->r_ctl.cur_rtt_send_time - bbr->r_ctl.bbr_ts_check_our_cts;
6163 if (delta < bbr_min_usec_delta) {
6164 /*
6165 * Have not seen a min amount of time
6166 * between our send times so we can
6167 * make a determination of the timestamp
6168 * yet.
6169 */
6170 return;
6171 }
6172 peer_delta = bbr->r_ctl.last_inbound_ts - bbr->r_ctl.bbr_ts_check_tstmp;
6173 if (peer_delta < bbr_min_peer_delta) {
6174 /*
6175 * We may have enough in the form of
6176 * our delta but the peers number
6177 * has not changed that much. It could
6178 * be its clock ratio is such that
6179 * we need more data (10ms tick) or
6180 * there may be other compression scenarios
6181 * going on. In any event we need the
6182 * spread to be larger.
6183 */
6184 return;
6185 }
6186 /* Ok lets first see which way our delta is going */
6187 if (peer_delta > delta) {
6188 /* Very unlikely, the peer without
6189 * compensation shows that it saw
6190 * the two sends arrive further apart
6191 * then we saw then in micro-seconds.
6192 */
6193 if (peer_delta < (delta + ((delta * (uint64_t)1000)/ (uint64_t)bbr_delta_percent))) {
6194 /* well it looks like the peer is a micro-second clock. */
6195 bbr->rc_ts_clock_set = 1;
6196 bbr->r_ctl.bbr_peer_tsratio = 1;
6197 } else {
6198 bbr->rc_ts_cant_be_used = 1;
6199 bbr->rc_ts_clock_set = 1;
6200 }
6201 return;
6202 }
6203 /* Ok we know that the peer_delta is smaller than our send distance */
6204 bbr->rc_ts_clock_set = 1;
6205 /* First question is it within the percentage that they are using usec time? */
6206 delta_up = (peer_delta * 1000) / (uint64_t)bbr_delta_percent;
6207 if ((peer_delta + delta_up) >= delta) {
6208 /* Its a usec clock */
6209 bbr->r_ctl.bbr_peer_tsratio = 1;
6210 bbr_log_tstmp_validation(bbr, peer_delta, delta);
6211 return;
6212 }
6213 /* Ok if not usec, what about 10usec (though unlikely)? */
6214 delta_up = (peer_delta * 1000 * 10) / (uint64_t)bbr_delta_percent;
6215 if (((peer_delta * 10) + delta_up) >= delta) {
6216 bbr->r_ctl.bbr_peer_tsratio = 10;
6217 bbr_log_tstmp_validation(bbr, peer_delta, delta);
6218 return;
6219 }
6220 /* And what about 100usec (though again unlikely)? */
6221 delta_up = (peer_delta * 1000 * 100) / (uint64_t)bbr_delta_percent;
6222 if (((peer_delta * 100) + delta_up) >= delta) {
6223 bbr->r_ctl.bbr_peer_tsratio = 100;
6224 bbr_log_tstmp_validation(bbr, peer_delta, delta);
6225 return;
6226 }
6227 /* And how about 1 msec (the most likely one)? */
6228 delta_up = (peer_delta * 1000 * 1000) / (uint64_t)bbr_delta_percent;
6229 if (((peer_delta * 1000) + delta_up) >= delta) {
6230 bbr->r_ctl.bbr_peer_tsratio = 1000;
6231 bbr_log_tstmp_validation(bbr, peer_delta, delta);
6232 return;
6233 }
6234 /* Ok if not msec could it be 10 msec? */
6235 delta_up = (peer_delta * 1000 * 10000) / (uint64_t)bbr_delta_percent;
6236 if (((peer_delta * 10000) + delta_up) >= delta) {
6237 bbr->r_ctl.bbr_peer_tsratio = 10000;
6238 return;
6239 }
6240 /* If we fall down here the clock tick so slowly we can't use it */
6241 bbr->rc_ts_cant_be_used = 1;
6242 bbr->r_ctl.bbr_peer_tsratio = 0;
6243 bbr_log_tstmp_validation(bbr, peer_delta, delta);
6244 }
6245
6246 /*
6247 * Collect new round-trip time estimate
6248 * and update averages and current timeout.
6249 */
6250 static void
6251 tcp_bbr_xmit_timer_commit(struct tcp_bbr *bbr, struct tcpcb *tp, uint32_t cts)
6252 {
6253 int32_t delta;
6254 uint32_t rtt, tsin;
6255 int32_t rtt_ticks;
6256
6257 if (bbr->rtt_valid == 0)
6258 /* No valid sample */
6259 return;
6260
6261 rtt = bbr->r_ctl.cur_rtt;
6262 tsin = bbr->r_ctl.ts_in;
6263 if (bbr->rc_prtt_set_ts) {
6264 /*
6265 * We are to force feed the rttProp filter due
6266 * to an entry into PROBE_RTT. This assures
6267 * that the times are sync'd between when we
6268 * go into PROBE_RTT and the filter expiration.
6269 *
6270 * Google does not use a true filter, so they do
6271 * this implicitly since they only keep one value
6272 * and when they enter probe-rtt they update the
6273 * value to the newest rtt.
6274 */
6275 uint32_t rtt_prop;
6276
6277 bbr->rc_prtt_set_ts = 0;
6278 rtt_prop = get_filter_value_small(&bbr->r_ctl.rc_rttprop);
6279 if (rtt > rtt_prop)
6280 filter_increase_by_small(&bbr->r_ctl.rc_rttprop, (rtt - rtt_prop), cts);
6281 else
6282 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts);
6283 }
6284 if (bbr->rc_ack_was_delayed)
6285 rtt += bbr->r_ctl.rc_ack_hdwr_delay;
6286
6287 if (rtt < bbr->r_ctl.rc_lowest_rtt)
6288 bbr->r_ctl.rc_lowest_rtt = rtt;
6289 bbr_log_rtt_sample(bbr, rtt, tsin);
6290 if (bbr->r_init_rtt) {
6291 /*
6292 * The initial rtt is not-trusted, nuke it and lets get
6293 * our first valid measurement in.
6294 */
6295 bbr->r_init_rtt = 0;
6296 tp->t_srtt = 0;
6297 }
6298 if ((bbr->rc_ts_clock_set == 0) && bbr->rc_ts_valid) {
6299 /*
6300 * So we have not yet figured out
6301 * what the peers TSTMP value is
6302 * in (most likely ms). We need a
6303 * series of cum-ack's to determine
6304 * this reliably.
6305 */
6306 if (bbr->rc_ack_is_cumack) {
6307 if (bbr->rc_ts_data_set) {
6308 /* Lets attempt to determine the timestamp granularity. */
6309 bbr_make_timestamp_determination(bbr);
6310 } else {
6311 bbr->rc_ts_data_set = 1;
6312 bbr->r_ctl.bbr_ts_check_tstmp = bbr->r_ctl.last_inbound_ts;
6313 bbr->r_ctl.bbr_ts_check_our_cts = bbr->r_ctl.cur_rtt_send_time;
6314 }
6315 } else {
6316 /*
6317 * We have to have consecutive acks
6318 * reset any "filled" state to none.
6319 */
6320 bbr->rc_ts_data_set = 0;
6321 }
6322 }
6323 /* Round it up */
6324 rtt_ticks = USEC_2_TICKS((rtt + (USECS_IN_MSEC - 1)));
6325 if (rtt_ticks == 0)
6326 rtt_ticks = 1;
6327 if (tp->t_srtt != 0) {
6328 /*
6329 * srtt is stored as fixed point with 5 bits after the
6330 * binary point (i.e., scaled by 8). The following magic is
6331 * equivalent to the smoothing algorithm in rfc793 with an
6332 * alpha of .875 (srtt = rtt/8 + srtt*7/8 in fixed point).
6333 * Adjust rtt to origin 0.
6334 */
6335
6336 delta = ((rtt_ticks - 1) << TCP_DELTA_SHIFT)
6337 - (tp->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT));
6338
6339 tp->t_srtt += delta;
6340 if (tp->t_srtt <= 0)
6341 tp->t_srtt = 1;
6342
6343 /*
6344 * We accumulate a smoothed rtt variance (actually, a
6345 * smoothed mean difference), then set the retransmit timer
6346 * to smoothed rtt + 4 times the smoothed variance. rttvar
6347 * is stored as fixed point with 4 bits after the binary
6348 * point (scaled by 16). The following is equivalent to
6349 * rfc793 smoothing with an alpha of .75 (rttvar =
6350 * rttvar*3/4 + |delta| / 4). This replaces rfc793's
6351 * wired-in beta.
6352 */
6353 if (delta < 0)
6354 delta = -delta;
6355 delta -= tp->t_rttvar >> (TCP_RTTVAR_SHIFT - TCP_DELTA_SHIFT);
6356 tp->t_rttvar += delta;
6357 if (tp->t_rttvar <= 0)
6358 tp->t_rttvar = 1;
6359 } else {
6360 /*
6361 * No rtt measurement yet - use the unsmoothed rtt. Set the
6362 * variance to half the rtt (so our first retransmit happens
6363 * at 3*rtt).
6364 */
6365 tp->t_srtt = rtt_ticks << TCP_RTT_SHIFT;
6366 tp->t_rttvar = rtt_ticks << (TCP_RTTVAR_SHIFT - 1);
6367 }
6368 KMOD_TCPSTAT_INC(tcps_rttupdated);
6369 if (tp->t_rttupdated < UCHAR_MAX)
6370 tp->t_rttupdated++;
6371 #ifdef STATS
6372 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RTT, imax(0, rtt_ticks));
6373 #endif
6374 /*
6375 * the retransmit should happen at rtt + 4 * rttvar. Because of the
6376 * way we do the smoothing, srtt and rttvar will each average +1/2
6377 * tick of bias. When we compute the retransmit timer, we want 1/2
6378 * tick of rounding and 1 extra tick because of +-1/2 tick
6379 * uncertainty in the firing of the timer. The bias will give us
6380 * exactly the 1.5 tick we need. But, because the bias is
6381 * statistical, we have to test that we don't drop below the minimum
6382 * feasible timer (which is 2 ticks).
6383 */
6384 TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp),
6385 max(MSEC_2_TICKS(bbr->r_ctl.rc_min_rto_ms), rtt_ticks + 2),
6386 MSEC_2_TICKS(((uint32_t)bbr->rc_max_rto_sec) * 1000));
6387
6388 /*
6389 * We received an ack for a packet that wasn't retransmitted; it is
6390 * probably safe to discard any error indications we've received
6391 * recently. This isn't quite right, but close enough for now (a
6392 * route might have failed after we sent a segment, and the return
6393 * path might not be symmetrical).
6394 */
6395 tp->t_softerror = 0;
6396 rtt = (TICKS_2_USEC(bbr->rc_tp->t_srtt) >> TCP_RTT_SHIFT);
6397 if (bbr->r_ctl.bbr_smallest_srtt_this_state > rtt)
6398 bbr->r_ctl.bbr_smallest_srtt_this_state = rtt;
6399 }
6400
6401 static void
6402 bbr_set_reduced_rtt(struct tcp_bbr *bbr, uint32_t cts, uint32_t line)
6403 {
6404 bbr->r_ctl.rc_rtt_shrinks = cts;
6405 if (bbr_can_force_probertt &&
6406 (TSTMP_GT(cts, bbr->r_ctl.last_in_probertt)) &&
6407 ((cts - bbr->r_ctl.last_in_probertt) > bbr->r_ctl.rc_probertt_int)) {
6408 /*
6409 * We should enter probe-rtt its been too long
6410 * since we have been there.
6411 */
6412 bbr_enter_probe_rtt(bbr, cts, __LINE__);
6413 } else
6414 bbr_check_probe_rtt_limits(bbr, cts);
6415 }
6416
6417 static void
6418 tcp_bbr_commit_bw(struct tcp_bbr *bbr, uint32_t cts)
6419 {
6420 uint64_t orig_bw;
6421
6422 if (bbr->r_ctl.rc_bbr_cur_del_rate == 0) {
6423 /* We never apply a zero measurement */
6424 bbr_log_type_bbrupd(bbr, 20, cts, 0, 0,
6425 0, 0, 0, 0, 0, 0);
6426 return;
6427 }
6428 if (bbr->r_ctl.r_measurement_count < 0xffffffff)
6429 bbr->r_ctl.r_measurement_count++;
6430 orig_bw = get_filter_value(&bbr->r_ctl.rc_delrate);
6431 apply_filter_max(&bbr->r_ctl.rc_delrate, bbr->r_ctl.rc_bbr_cur_del_rate, bbr->r_ctl.rc_pkt_epoch);
6432 bbr_log_type_bbrupd(bbr, 21, cts, (uint32_t)orig_bw,
6433 (uint32_t)get_filter_value(&bbr->r_ctl.rc_delrate),
6434 0, 0, 0, 0, 0, 0);
6435 if (orig_bw &&
6436 (orig_bw != get_filter_value(&bbr->r_ctl.rc_delrate))) {
6437 if (bbr->bbr_hdrw_pacing) {
6438 /*
6439 * Apply a new rate to the hardware
6440 * possibly.
6441 */
6442 bbr_update_hardware_pacing_rate(bbr, cts);
6443 }
6444 bbr_set_state_target(bbr, __LINE__);
6445 tcp_bbr_tso_size_check(bbr, cts);
6446 if (bbr->r_recovery_bw) {
6447 bbr_setup_red_bw(bbr, cts);
6448 bbr_log_type_bw_reduce(bbr, BBR_RED_BW_USELRBW);
6449 }
6450 } else if ((orig_bw == 0) && get_filter_value(&bbr->r_ctl.rc_delrate))
6451 tcp_bbr_tso_size_check(bbr, cts);
6452 }
6453
6454 static void
6455 bbr_nf_measurement(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t rtt, uint32_t cts)
6456 {
6457 if (bbr->rc_in_persist == 0) {
6458 /* We log only when not in persist */
6459 /* Translate to a Bytes Per Second */
6460 uint64_t tim, bw, ts_diff, ts_bw;
6461 uint32_t delivered;
6462
6463 if (TSTMP_GT(bbr->r_ctl.rc_del_time, rsm->r_del_time))
6464 tim = (uint64_t)(bbr->r_ctl.rc_del_time - rsm->r_del_time);
6465 else
6466 tim = 1;
6467 /*
6468 * Now that we have processed the tim (skipping the sample
6469 * or possibly updating the time, go ahead and
6470 * calculate the cdr.
6471 */
6472 delivered = (bbr->r_ctl.rc_delivered - rsm->r_delivered);
6473 bw = (uint64_t)delivered;
6474 bw *= (uint64_t)USECS_IN_SECOND;
6475 bw /= tim;
6476 if (bw == 0) {
6477 /* We must have a calculatable amount */
6478 return;
6479 }
6480 /*
6481 * If we are using this b/w shove it in now so we
6482 * can see in the trace viewer if it gets over-ridden.
6483 */
6484 if (rsm->r_ts_valid &&
6485 bbr->rc_ts_valid &&
6486 bbr->rc_ts_clock_set &&
6487 (bbr->rc_ts_cant_be_used == 0) &&
6488 bbr->rc_use_ts_limit) {
6489 ts_diff = max((bbr->r_ctl.last_inbound_ts - rsm->r_del_ack_ts), 1);
6490 ts_diff *= bbr->r_ctl.bbr_peer_tsratio;
6491 if ((delivered == 0) ||
6492 (rtt < 1000)) {
6493 /* Can't use the ts */
6494 bbr_log_type_bbrupd(bbr, 61, cts,
6495 ts_diff,
6496 bbr->r_ctl.last_inbound_ts,
6497 rsm->r_del_ack_ts, 0,
6498 0, 0, 0, delivered);
6499 } else {
6500 ts_bw = (uint64_t)delivered;
6501 ts_bw *= (uint64_t)USECS_IN_SECOND;
6502 ts_bw /= ts_diff;
6503 bbr_log_type_bbrupd(bbr, 62, cts,
6504 (ts_bw >> 32),
6505 (ts_bw & 0xffffffff), 0, 0,
6506 0, 0, ts_diff, delivered);
6507 if ((bbr->ts_can_raise) &&
6508 (ts_bw > bw)) {
6509 bbr_log_type_bbrupd(bbr, 8, cts,
6510 delivered,
6511 ts_diff,
6512 (bw >> 32),
6513 (bw & 0x00000000ffffffff),
6514 0, 0, 0, 0);
6515 bw = ts_bw;
6516 } else if (ts_bw && (ts_bw < bw)) {
6517 bbr_log_type_bbrupd(bbr, 7, cts,
6518 delivered,
6519 ts_diff,
6520 (bw >> 32),
6521 (bw & 0x00000000ffffffff),
6522 0, 0, 0, 0);
6523 bw = ts_bw;
6524 }
6525 }
6526 }
6527 if (rsm->r_first_sent_time &&
6528 TSTMP_GT(rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)],rsm->r_first_sent_time)) {
6529 uint64_t sbw, sti;
6530 /*
6531 * We use what was in flight at the time of our
6532 * send and the size of this send to figure
6533 * out what we have been sending at (amount).
6534 * For the time we take from the time of
6535 * the send of the first send outstanding
6536 * until this send plus this sends pacing
6537 * time. This gives us a good calculation
6538 * as to the rate we have been sending at.
6539 */
6540
6541 sbw = (uint64_t)(rsm->r_flight_at_send);
6542 sbw *= (uint64_t)USECS_IN_SECOND;
6543 sti = rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)] - rsm->r_first_sent_time;
6544 sti += rsm->r_pacing_delay;
6545 sbw /= sti;
6546 if (sbw < bw) {
6547 bbr_log_type_bbrupd(bbr, 6, cts,
6548 delivered,
6549 (uint32_t)sti,
6550 (bw >> 32),
6551 (uint32_t)bw,
6552 rsm->r_first_sent_time, 0, (sbw >> 32),
6553 (uint32_t)sbw);
6554 bw = sbw;
6555 }
6556 }
6557 /* Use the google algorithm for b/w measurements */
6558 bbr->r_ctl.rc_bbr_cur_del_rate = bw;
6559 if ((rsm->r_app_limited == 0) ||
6560 (bw > get_filter_value(&bbr->r_ctl.rc_delrate))) {
6561 tcp_bbr_commit_bw(bbr, cts);
6562 bbr_log_type_bbrupd(bbr, 10, cts, (uint32_t)tim, delivered,
6563 0, 0, 0, 0, bbr->r_ctl.rc_del_time, rsm->r_del_time);
6564 }
6565 }
6566 }
6567
6568 static void
6569 bbr_google_measurement(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t rtt, uint32_t cts)
6570 {
6571 if (bbr->rc_in_persist == 0) {
6572 /* We log only when not in persist */
6573 /* Translate to a Bytes Per Second */
6574 uint64_t tim, bw;
6575 uint32_t delivered;
6576 int no_apply = 0;
6577
6578 if (TSTMP_GT(bbr->r_ctl.rc_del_time, rsm->r_del_time))
6579 tim = (uint64_t)(bbr->r_ctl.rc_del_time - rsm->r_del_time);
6580 else
6581 tim = 1;
6582 /*
6583 * Now that we have processed the tim (skipping the sample
6584 * or possibly updating the time, go ahead and
6585 * calculate the cdr.
6586 */
6587 delivered = (bbr->r_ctl.rc_delivered - rsm->r_delivered);
6588 bw = (uint64_t)delivered;
6589 bw *= (uint64_t)USECS_IN_SECOND;
6590 bw /= tim;
6591 if (tim < bbr->r_ctl.rc_lowest_rtt) {
6592 bbr_log_type_bbrupd(bbr, 99, cts, (uint32_t)tim, delivered,
6593 tim, bbr->r_ctl.rc_lowest_rtt, 0, 0, 0, 0);
6594
6595 no_apply = 1;
6596 }
6597 /*
6598 * If we are using this b/w shove it in now so we
6599 * can see in the trace viewer if it gets over-ridden.
6600 */
6601 bbr->r_ctl.rc_bbr_cur_del_rate = bw;
6602 /* Gate by the sending rate */
6603 if (rsm->r_first_sent_time &&
6604 TSTMP_GT(rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)],rsm->r_first_sent_time)) {
6605 uint64_t sbw, sti;
6606 /*
6607 * We use what was in flight at the time of our
6608 * send and the size of this send to figure
6609 * out what we have been sending at (amount).
6610 * For the time we take from the time of
6611 * the send of the first send outstanding
6612 * until this send plus this sends pacing
6613 * time. This gives us a good calculation
6614 * as to the rate we have been sending at.
6615 */
6616
6617 sbw = (uint64_t)(rsm->r_flight_at_send);
6618 sbw *= (uint64_t)USECS_IN_SECOND;
6619 sti = rsm->r_tim_lastsent[(rsm->r_rtr_cnt -1)] - rsm->r_first_sent_time;
6620 sti += rsm->r_pacing_delay;
6621 sbw /= sti;
6622 if (sbw < bw) {
6623 bbr_log_type_bbrupd(bbr, 6, cts,
6624 delivered,
6625 (uint32_t)sti,
6626 (bw >> 32),
6627 (uint32_t)bw,
6628 rsm->r_first_sent_time, 0, (sbw >> 32),
6629 (uint32_t)sbw);
6630 bw = sbw;
6631 }
6632 if ((sti > tim) &&
6633 (sti < bbr->r_ctl.rc_lowest_rtt)) {
6634 bbr_log_type_bbrupd(bbr, 99, cts, (uint32_t)tim, delivered,
6635 (uint32_t)sti, bbr->r_ctl.rc_lowest_rtt, 0, 0, 0, 0);
6636 no_apply = 1;
6637 } else
6638 no_apply = 0;
6639 }
6640 bbr->r_ctl.rc_bbr_cur_del_rate = bw;
6641 if ((no_apply == 0) &&
6642 ((rsm->r_app_limited == 0) ||
6643 (bw > get_filter_value(&bbr->r_ctl.rc_delrate)))) {
6644 tcp_bbr_commit_bw(bbr, cts);
6645 bbr_log_type_bbrupd(bbr, 10, cts, (uint32_t)tim, delivered,
6646 0, 0, 0, 0, bbr->r_ctl.rc_del_time, rsm->r_del_time);
6647 }
6648 }
6649 }
6650
6651 static void
6652 bbr_update_bbr_info(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, uint32_t rtt, uint32_t cts, uint32_t tsin,
6653 uint32_t uts, int32_t match, uint32_t rsm_send_time, int32_t ack_type, struct tcpopt *to)
6654 {
6655 uint64_t old_rttprop;
6656
6657 /* Update our delivery time and amount */
6658 bbr->r_ctl.rc_delivered += (rsm->r_end - rsm->r_start);
6659 bbr->r_ctl.rc_del_time = cts;
6660 if (rtt == 0) {
6661 /*
6662 * 0 means its a retransmit, for now we don't use these for
6663 * the rest of BBR.
6664 */
6665 return;
6666 }
6667 if ((bbr->rc_use_google == 0) &&
6668 (match != BBR_RTT_BY_EXACTMATCH) &&
6669 (match != BBR_RTT_BY_TIMESTAMP)){
6670 /*
6671 * We get a lot of rtt updates, lets not pay attention to
6672 * any that are not an exact match. That way we don't have
6673 * to worry about timestamps and the whole nonsense of
6674 * unsure if its a retransmission etc (if we ever had the
6675 * timestamp fixed to always have the last thing sent this
6676 * would not be a issue).
6677 */
6678 return;
6679 }
6680 if ((bbr_no_retran && bbr->rc_use_google) &&
6681 (match != BBR_RTT_BY_EXACTMATCH) &&
6682 (match != BBR_RTT_BY_TIMESTAMP)){
6683 /*
6684 * We only do measurements in google mode
6685 * with bbr_no_retran on for sure things.
6686 */
6687 return;
6688 }
6689 /* Only update srtt if we know by exact match */
6690 tcp_bbr_xmit_timer(bbr, rtt, rsm_send_time, rsm->r_start, tsin);
6691 if (ack_type == BBR_CUM_ACKED)
6692 bbr->rc_ack_is_cumack = 1;
6693 else
6694 bbr->rc_ack_is_cumack = 0;
6695 old_rttprop = bbr_get_rtt(bbr, BBR_RTT_PROP);
6696 /*
6697 * Note the following code differs to the original
6698 * BBR spec. It calls for <= not <. However after a
6699 * long discussion in email with Neal, he acknowledged
6700 * that it should be < than so that we will have flows
6701 * going into probe-rtt (we were seeing cases where that
6702 * did not happen and caused ugly things to occur). We
6703 * have added this agreed upon fix to our code base.
6704 */
6705 if (rtt < old_rttprop) {
6706 /* Update when we last saw a rtt drop */
6707 bbr_log_rtt_shrinks(bbr, cts, 0, rtt, __LINE__, BBR_RTTS_NEWRTT, 0);
6708 bbr_set_reduced_rtt(bbr, cts, __LINE__);
6709 }
6710 bbr_log_type_bbrrttprop(bbr, rtt, (rsm ? rsm->r_end : 0), uts, cts,
6711 match, rsm->r_start, rsm->r_flags);
6712 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts);
6713 if (old_rttprop != bbr_get_rtt(bbr, BBR_RTT_PROP)) {
6714 /*
6715 * The RTT-prop moved, reset the target (may be a
6716 * nop for some states).
6717 */
6718 bbr_set_state_target(bbr, __LINE__);
6719 if (bbr->rc_bbr_state == BBR_STATE_PROBE_RTT)
6720 bbr_log_rtt_shrinks(bbr, cts, 0, 0,
6721 __LINE__, BBR_RTTS_NEW_TARGET, 0);
6722 else if (old_rttprop < bbr_get_rtt(bbr, BBR_RTT_PROP))
6723 /* It went up */
6724 bbr_check_probe_rtt_limits(bbr, cts);
6725 }
6726 if ((bbr->rc_use_google == 0) &&
6727 (match == BBR_RTT_BY_TIMESTAMP)) {
6728 /*
6729 * We don't do b/w update with
6730 * these since they are not really
6731 * reliable.
6732 */
6733 return;
6734 }
6735 if (bbr->r_ctl.r_app_limited_until &&
6736 (bbr->r_ctl.rc_delivered >= bbr->r_ctl.r_app_limited_until)) {
6737 /* We are no longer app-limited */
6738 bbr->r_ctl.r_app_limited_until = 0;
6739 }
6740 if (bbr->rc_use_google) {
6741 bbr_google_measurement(bbr, rsm, rtt, cts);
6742 } else {
6743 bbr_nf_measurement(bbr, rsm, rtt, cts);
6744 }
6745 }
6746
6747 /*
6748 * Convert a timestamp that the main stack
6749 * uses (milliseconds) into one that bbr uses
6750 * (microseconds). Return that converted timestamp.
6751 */
6752 static uint32_t
6753 bbr_ts_convert(uint32_t cts) {
6754 uint32_t sec, msec;
6755
6756 sec = cts / MS_IN_USEC;
6757 msec = cts - (MS_IN_USEC * sec);
6758 return ((sec * USECS_IN_SECOND) + (msec * MS_IN_USEC));
6759 }
6760
6761 /*
6762 * Return 0 if we did not update the RTT time, return
6763 * 1 if we did.
6764 */
6765 static int
6766 bbr_update_rtt(struct tcpcb *tp, struct tcp_bbr *bbr,
6767 struct bbr_sendmap *rsm, struct tcpopt *to, uint32_t cts, int32_t ack_type, uint32_t th_ack)
6768 {
6769 int32_t i;
6770 uint32_t t, uts = 0;
6771
6772 if ((rsm->r_flags & BBR_ACKED) ||
6773 (rsm->r_flags & BBR_WAS_RENEGED) ||
6774 (rsm->r_flags & BBR_RXT_CLEARED)) {
6775 /* Already done */
6776 return (0);
6777 }
6778 if (rsm->r_rtt_not_allowed) {
6779 /* Not allowed */
6780 return (0);
6781 }
6782 if (rsm->r_rtr_cnt == 1) {
6783 /*
6784 * Only one transmit. Hopefully the normal case.
6785 */
6786 if (TSTMP_GT(cts, rsm->r_tim_lastsent[0]))
6787 t = cts - rsm->r_tim_lastsent[0];
6788 else
6789 t = 1;
6790 if ((int)t <= 0)
6791 t = 1;
6792 bbr->r_ctl.rc_last_rtt = t;
6793 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, 0,
6794 BBR_RTT_BY_EXACTMATCH, rsm->r_tim_lastsent[0], ack_type, to);
6795 return (1);
6796 }
6797 /* Convert to usecs */
6798 if ((bbr_can_use_ts_for_rtt == 1) &&
6799 (bbr->rc_use_google == 1) &&
6800 (ack_type == BBR_CUM_ACKED) &&
6801 (to->to_flags & TOF_TS) &&
6802 (to->to_tsecr != 0)) {
6803 t = tcp_tv_to_mssectick(&bbr->rc_tv) - to->to_tsecr;
6804 if (t < 1)
6805 t = 1;
6806 t *= MS_IN_USEC;
6807 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, 0,
6808 BBR_RTT_BY_TIMESTAMP,
6809 rsm->r_tim_lastsent[(rsm->r_rtr_cnt-1)],
6810 ack_type, to);
6811 return (1);
6812 }
6813 uts = bbr_ts_convert(to->to_tsecr);
6814 if ((to->to_flags & TOF_TS) &&
6815 (to->to_tsecr != 0) &&
6816 (ack_type == BBR_CUM_ACKED) &&
6817 ((rsm->r_flags & BBR_OVERMAX) == 0)) {
6818 /*
6819 * Now which timestamp does it match? In this block the ACK
6820 * may be coming from a previous transmission.
6821 */
6822 uint32_t fudge;
6823
6824 fudge = BBR_TIMER_FUDGE;
6825 for (i = 0; i < rsm->r_rtr_cnt; i++) {
6826 if ((SEQ_GEQ(uts, (rsm->r_tim_lastsent[i] - fudge))) &&
6827 (SEQ_LEQ(uts, (rsm->r_tim_lastsent[i] + fudge)))) {
6828 if (TSTMP_GT(cts, rsm->r_tim_lastsent[i]))
6829 t = cts - rsm->r_tim_lastsent[i];
6830 else
6831 t = 1;
6832 if ((int)t <= 0)
6833 t = 1;
6834 bbr->r_ctl.rc_last_rtt = t;
6835 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, uts, BBR_RTT_BY_TSMATCHING,
6836 rsm->r_tim_lastsent[i], ack_type, to);
6837 if ((i + 1) < rsm->r_rtr_cnt) {
6838 /* Likely */
6839 return (0);
6840 } else if (rsm->r_flags & BBR_TLP) {
6841 bbr->rc_tlp_rtx_out = 0;
6842 }
6843 return (1);
6844 }
6845 }
6846 /* Fall through if we can't find a matching timestamp */
6847 }
6848 /*
6849 * Ok its a SACK block that we retransmitted. or a windows
6850 * machine without timestamps. We can tell nothing from the
6851 * time-stamp since its not there or the time the peer last
6852 * recieved a segment that moved forward its cum-ack point.
6853 *
6854 * Lets look at the last retransmit and see what we can tell
6855 * (with BBR for space we only keep 2 note we have to keep
6856 * at least 2 so the map can not be condensed more).
6857 */
6858 i = rsm->r_rtr_cnt - 1;
6859 if (TSTMP_GT(cts, rsm->r_tim_lastsent[i]))
6860 t = cts - rsm->r_tim_lastsent[i];
6861 else
6862 goto not_sure;
6863 if (t < bbr->r_ctl.rc_lowest_rtt) {
6864 /*
6865 * We retransmitted and the ack came back in less
6866 * than the smallest rtt we have observed in the
6867 * windowed rtt. We most likey did an improper
6868 * retransmit as outlined in 4.2 Step 3 point 2 in
6869 * the rack-draft.
6870 *
6871 * Use the prior transmission to update all the
6872 * information as long as there is only one prior
6873 * transmission.
6874 */
6875 if ((rsm->r_flags & BBR_OVERMAX) == 0) {
6876 #ifdef BBR_INVARIANTS
6877 if (rsm->r_rtr_cnt == 1)
6878 panic("rsm:%p bbr:%p rsm has overmax and only 1 retranmit flags:%x?", rsm, bbr, rsm->r_flags);
6879 #endif
6880 i = rsm->r_rtr_cnt - 2;
6881 if (TSTMP_GT(cts, rsm->r_tim_lastsent[i]))
6882 t = cts - rsm->r_tim_lastsent[i];
6883 else
6884 t = 1;
6885 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, uts, BBR_RTT_BY_EARLIER_RET,
6886 rsm->r_tim_lastsent[i], ack_type, to);
6887 return (0);
6888 } else {
6889 /*
6890 * Too many prior transmissions, just
6891 * updated BBR delivered
6892 */
6893 not_sure:
6894 bbr_update_bbr_info(bbr, rsm, 0, cts, to->to_tsecr, uts,
6895 BBR_RTT_BY_SOME_RETRAN, 0, ack_type, to);
6896 }
6897 } else {
6898 /*
6899 * We retransmitted it and the retransmit did the
6900 * job.
6901 */
6902 if (rsm->r_flags & BBR_TLP)
6903 bbr->rc_tlp_rtx_out = 0;
6904 if ((rsm->r_flags & BBR_OVERMAX) == 0)
6905 bbr_update_bbr_info(bbr, rsm, t, cts, to->to_tsecr, uts,
6906 BBR_RTT_BY_THIS_RETRAN, 0, ack_type, to);
6907 else
6908 bbr_update_bbr_info(bbr, rsm, 0, cts, to->to_tsecr, uts,
6909 BBR_RTT_BY_SOME_RETRAN, 0, ack_type, to);
6910 return (1);
6911 }
6912 return (0);
6913 }
6914
6915 /*
6916 * Mark the SACK_PASSED flag on all entries prior to rsm send wise.
6917 */
6918 static void
6919 bbr_log_sack_passed(struct tcpcb *tp,
6920 struct tcp_bbr *bbr, struct bbr_sendmap *rsm)
6921 {
6922 struct bbr_sendmap *nrsm;
6923
6924 nrsm = rsm;
6925 TAILQ_FOREACH_REVERSE_FROM(nrsm, &bbr->r_ctl.rc_tmap,
6926 bbr_head, r_tnext) {
6927 if (nrsm == rsm) {
6928 /* Skip original segment he is acked */
6929 continue;
6930 }
6931 if (nrsm->r_flags & BBR_ACKED) {
6932 /* Skip ack'd segments */
6933 continue;
6934 }
6935 if (nrsm->r_flags & BBR_SACK_PASSED) {
6936 /*
6937 * We found one that is already marked
6938 * passed, we have been here before and
6939 * so all others below this are marked.
6940 */
6941 break;
6942 }
6943 BBR_STAT_INC(bbr_sack_passed);
6944 nrsm->r_flags |= BBR_SACK_PASSED;
6945 if (((nrsm->r_flags & BBR_MARKED_LOST) == 0) &&
6946 bbr_is_lost(bbr, nrsm, bbr->r_ctl.rc_rcvtime)) {
6947 bbr->r_ctl.rc_lost += nrsm->r_end - nrsm->r_start;
6948 bbr->r_ctl.rc_lost_bytes += nrsm->r_end - nrsm->r_start;
6949 nrsm->r_flags |= BBR_MARKED_LOST;
6950 }
6951 nrsm->r_flags &= ~BBR_WAS_SACKPASS;
6952 }
6953 }
6954
6955 /*
6956 * Returns the number of bytes that were
6957 * newly ack'd by sack blocks.
6958 */
6959 static uint32_t
6960 bbr_proc_sack_blk(struct tcpcb *tp, struct tcp_bbr *bbr, struct sackblk *sack,
6961 struct tcpopt *to, struct bbr_sendmap **prsm, uint32_t cts)
6962 {
6963 int32_t times = 0;
6964 uint32_t start, end, changed = 0;
6965 struct bbr_sendmap *rsm, *nrsm;
6966 int32_t used_ref = 1;
6967 uint8_t went_back = 0, went_fwd = 0;
6968
6969 start = sack->start;
6970 end = sack->end;
6971 rsm = *prsm;
6972 if (rsm == NULL)
6973 used_ref = 0;
6974
6975 /* Do we locate the block behind where we last were? */
6976 if (rsm && SEQ_LT(start, rsm->r_start)) {
6977 went_back = 1;
6978 TAILQ_FOREACH_REVERSE_FROM(rsm, &bbr->r_ctl.rc_map, bbr_head, r_next) {
6979 if (SEQ_GEQ(start, rsm->r_start) &&
6980 SEQ_LT(start, rsm->r_end)) {
6981 goto do_rest_ofb;
6982 }
6983 }
6984 }
6985 start_at_beginning:
6986 went_fwd = 1;
6987 /*
6988 * Ok lets locate the block where this guy is fwd from rsm (if its
6989 * set)
6990 */
6991 TAILQ_FOREACH_FROM(rsm, &bbr->r_ctl.rc_map, r_next) {
6992 if (SEQ_GEQ(start, rsm->r_start) &&
6993 SEQ_LT(start, rsm->r_end)) {
6994 break;
6995 }
6996 }
6997 do_rest_ofb:
6998 if (rsm == NULL) {
6999 /*
7000 * This happens when we get duplicate sack blocks with the
7001 * same end. For example SACK 4: 100 SACK 3: 100 The sort
7002 * will not change there location so we would just start at
7003 * the end of the first one and get lost.
7004 */
7005 if (tp->t_flags & TF_SENTFIN) {
7006 /*
7007 * Check to see if we have not logged the FIN that
7008 * went out.
7009 */
7010 nrsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_map, bbr_sendmap, r_next);
7011 if (nrsm && (nrsm->r_end + 1) == tp->snd_max) {
7012 /*
7013 * Ok we did not get the FIN logged.
7014 */
7015 nrsm->r_end++;
7016 rsm = nrsm;
7017 goto do_rest_ofb;
7018 }
7019 }
7020 if (times == 1) {
7021 #ifdef BBR_INVARIANTS
7022 panic("tp:%p bbr:%p sack:%p to:%p prsm:%p",
7023 tp, bbr, sack, to, prsm);
7024 #else
7025 goto out;
7026 #endif
7027 }
7028 times++;
7029 BBR_STAT_INC(bbr_sack_proc_restart);
7030 rsm = NULL;
7031 goto start_at_beginning;
7032 }
7033 /* Ok we have an ACK for some piece of rsm */
7034 if (rsm->r_start != start) {
7035 /*
7036 * Need to split this in two pieces the before and after.
7037 */
7038 if (bbr_sack_mergable(rsm, start, end))
7039 nrsm = bbr_alloc_full_limit(bbr);
7040 else
7041 nrsm = bbr_alloc_limit(bbr, BBR_LIMIT_TYPE_SPLIT);
7042 if (nrsm == NULL) {
7043 /* We could not allocate ignore the sack */
7044 struct sackblk blk;
7045
7046 blk.start = start;
7047 blk.end = end;
7048 sack_filter_reject(&bbr->r_ctl.bbr_sf, &blk);
7049 goto out;
7050 }
7051 bbr_clone_rsm(bbr, nrsm, rsm, start);
7052 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next);
7053 if (rsm->r_in_tmap) {
7054 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext);
7055 nrsm->r_in_tmap = 1;
7056 }
7057 rsm->r_flags &= (~BBR_HAS_FIN);
7058 rsm = nrsm;
7059 }
7060 if (SEQ_GEQ(end, rsm->r_end)) {
7061 /*
7062 * The end of this block is either beyond this guy or right
7063 * at this guy.
7064 */
7065 if ((rsm->r_flags & BBR_ACKED) == 0) {
7066 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_SACKED, 0);
7067 changed += (rsm->r_end - rsm->r_start);
7068 bbr->r_ctl.rc_sacked += (rsm->r_end - rsm->r_start);
7069 bbr_log_sack_passed(tp, bbr, rsm);
7070 if (rsm->r_flags & BBR_MARKED_LOST) {
7071 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start;
7072 }
7073 /* Is Reordering occuring? */
7074 if (rsm->r_flags & BBR_SACK_PASSED) {
7075 BBR_STAT_INC(bbr_reorder_seen);
7076 bbr->r_ctl.rc_reorder_ts = cts;
7077 if (rsm->r_flags & BBR_MARKED_LOST) {
7078 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start;
7079 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost))
7080 /* LT sampling also needs adjustment */
7081 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost;
7082 }
7083 }
7084 rsm->r_flags |= BBR_ACKED;
7085 rsm->r_flags &= ~(BBR_TLP|BBR_WAS_RENEGED|BBR_RXT_CLEARED|BBR_MARKED_LOST);
7086 if (rsm->r_in_tmap) {
7087 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
7088 rsm->r_in_tmap = 0;
7089 }
7090 }
7091 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_SACKED);
7092 if (end == rsm->r_end) {
7093 /* This block only - done */
7094 goto out;
7095 }
7096 /* There is more not coverend by this rsm move on */
7097 start = rsm->r_end;
7098 nrsm = TAILQ_NEXT(rsm, r_next);
7099 rsm = nrsm;
7100 times = 0;
7101 goto do_rest_ofb;
7102 }
7103 if (rsm->r_flags & BBR_ACKED) {
7104 /* Been here done that */
7105 goto out;
7106 }
7107 /* Ok we need to split off this one at the tail */
7108 if (bbr_sack_mergable(rsm, start, end))
7109 nrsm = bbr_alloc_full_limit(bbr);
7110 else
7111 nrsm = bbr_alloc_limit(bbr, BBR_LIMIT_TYPE_SPLIT);
7112 if (nrsm == NULL) {
7113 /* failed XXXrrs what can we do but loose the sack info? */
7114 struct sackblk blk;
7115
7116 blk.start = start;
7117 blk.end = end;
7118 sack_filter_reject(&bbr->r_ctl.bbr_sf, &blk);
7119 goto out;
7120 }
7121 /* Clone it */
7122 bbr_clone_rsm(bbr, nrsm, rsm, end);
7123 /* The sack block does not cover this guy fully */
7124 rsm->r_flags &= (~BBR_HAS_FIN);
7125 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next);
7126 if (rsm->r_in_tmap) {
7127 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext);
7128 nrsm->r_in_tmap = 1;
7129 }
7130 nrsm->r_dupack = 0;
7131 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_SACKED, 0);
7132 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_SACKED);
7133 changed += (rsm->r_end - rsm->r_start);
7134 bbr->r_ctl.rc_sacked += (rsm->r_end - rsm->r_start);
7135 bbr_log_sack_passed(tp, bbr, rsm);
7136 /* Is Reordering occuring? */
7137 if (rsm->r_flags & BBR_MARKED_LOST) {
7138 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start;
7139 }
7140 if (rsm->r_flags & BBR_SACK_PASSED) {
7141 BBR_STAT_INC(bbr_reorder_seen);
7142 bbr->r_ctl.rc_reorder_ts = cts;
7143 if (rsm->r_flags & BBR_MARKED_LOST) {
7144 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start;
7145 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost))
7146 /* LT sampling also needs adjustment */
7147 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost;
7148 }
7149 }
7150 rsm->r_flags &= ~(BBR_TLP|BBR_WAS_RENEGED|BBR_RXT_CLEARED|BBR_MARKED_LOST);
7151 rsm->r_flags |= BBR_ACKED;
7152 if (rsm->r_in_tmap) {
7153 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
7154 rsm->r_in_tmap = 0;
7155 }
7156 out:
7157 if (rsm && (rsm->r_flags & BBR_ACKED)) {
7158 /*
7159 * Now can we merge this newly acked
7160 * block with either the previous or
7161 * next block?
7162 */
7163 nrsm = TAILQ_NEXT(rsm, r_next);
7164 if (nrsm &&
7165 (nrsm->r_flags & BBR_ACKED)) {
7166 /* yep this and next can be merged */
7167 rsm = bbr_merge_rsm(bbr, rsm, nrsm);
7168 }
7169 /* Now what about the previous? */
7170 nrsm = TAILQ_PREV(rsm, bbr_head, r_next);
7171 if (nrsm &&
7172 (nrsm->r_flags & BBR_ACKED)) {
7173 /* yep the previous and this can be merged */
7174 rsm = bbr_merge_rsm(bbr, nrsm, rsm);
7175 }
7176 }
7177 if (used_ref == 0) {
7178 BBR_STAT_INC(bbr_sack_proc_all);
7179 } else {
7180 BBR_STAT_INC(bbr_sack_proc_short);
7181 }
7182 if (went_fwd && went_back) {
7183 BBR_STAT_INC(bbr_sack_search_both);
7184 } else if (went_fwd) {
7185 BBR_STAT_INC(bbr_sack_search_fwd);
7186 } else if (went_back) {
7187 BBR_STAT_INC(bbr_sack_search_back);
7188 }
7189 /* Save off where the next seq is */
7190 if (rsm)
7191 bbr->r_ctl.rc_sacklast = TAILQ_NEXT(rsm, r_next);
7192 else
7193 bbr->r_ctl.rc_sacklast = NULL;
7194 *prsm = rsm;
7195 return (changed);
7196 }
7197
7198 static void inline
7199 bbr_peer_reneges(struct tcp_bbr *bbr, struct bbr_sendmap *rsm, tcp_seq th_ack)
7200 {
7201 struct bbr_sendmap *tmap;
7202
7203 BBR_STAT_INC(bbr_reneges_seen);
7204 tmap = NULL;
7205 while (rsm && (rsm->r_flags & BBR_ACKED)) {
7206 /* Its no longer sacked, mark it so */
7207 uint32_t oflags;
7208 bbr->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start);
7209 #ifdef BBR_INVARIANTS
7210 if (rsm->r_in_tmap) {
7211 panic("bbr:%p rsm:%p flags:0x%x in tmap?",
7212 bbr, rsm, rsm->r_flags);
7213 }
7214 #endif
7215 oflags = rsm->r_flags;
7216 if (rsm->r_flags & BBR_MARKED_LOST) {
7217 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start;
7218 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start;
7219 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost))
7220 /* LT sampling also needs adjustment */
7221 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost;
7222 }
7223 rsm->r_flags &= ~(BBR_ACKED | BBR_SACK_PASSED | BBR_WAS_SACKPASS | BBR_MARKED_LOST);
7224 rsm->r_flags |= BBR_WAS_RENEGED;
7225 rsm->r_flags |= BBR_RXT_CLEARED;
7226 bbr_log_type_rsmclear(bbr, bbr->r_ctl.rc_rcvtime, rsm, oflags, __LINE__);
7227 /* Rebuild it into our tmap */
7228 if (tmap == NULL) {
7229 TAILQ_INSERT_HEAD(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
7230 tmap = rsm;
7231 } else {
7232 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, tmap, rsm, r_tnext);
7233 tmap = rsm;
7234 }
7235 tmap->r_in_tmap = 1;
7236 /*
7237 * XXXrrs Delivered? Should we do anything here?
7238 *
7239 * Of course we don't on a rxt timeout so maybe its ok that
7240 * we don't?
7241 *
7242 * For now lets not.
7243 */
7244 rsm = TAILQ_NEXT(rsm, r_next);
7245 }
7246 /*
7247 * Now lets possibly clear the sack filter so we start recognizing
7248 * sacks that cover this area.
7249 */
7250 sack_filter_clear(&bbr->r_ctl.bbr_sf, th_ack);
7251 }
7252
7253 static void
7254 bbr_log_syn(struct tcpcb *tp, struct tcpopt *to)
7255 {
7256 struct tcp_bbr *bbr;
7257 struct bbr_sendmap *rsm;
7258 uint32_t cts;
7259
7260 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
7261 cts = bbr->r_ctl.rc_rcvtime;
7262 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map);
7263 if (rsm && (rsm->r_flags & BBR_HAS_SYN)) {
7264 if ((rsm->r_end - rsm->r_start) <= 1) {
7265 /* Log out the SYN completely */
7266 bbr->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes;
7267 rsm->r_rtr_bytes = 0;
7268 TAILQ_REMOVE(&bbr->r_ctl.rc_map, rsm, r_next);
7269 if (rsm->r_in_tmap) {
7270 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
7271 rsm->r_in_tmap = 0;
7272 }
7273 if (bbr->r_ctl.rc_next == rsm) {
7274 /* scoot along the marker */
7275 bbr->r_ctl.rc_next = TAILQ_FIRST(&bbr->r_ctl.rc_map);
7276 }
7277 if (to != NULL)
7278 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_CUM_ACKED, 0);
7279 bbr_free(bbr, rsm);
7280 } else {
7281 /* There is more (Fast open)? strip out SYN. */
7282 rsm->r_flags &= ~BBR_HAS_SYN;
7283 rsm->r_start++;
7284 }
7285 }
7286 }
7287
7288 /*
7289 * Returns the number of bytes that were
7290 * acknowledged by SACK blocks.
7291 */
7292
7293 static uint32_t
7294 bbr_log_ack(struct tcpcb *tp, struct tcpopt *to, struct tcphdr *th,
7295 uint32_t *prev_acked)
7296 {
7297 uint32_t changed, last_seq, entered_recovery = 0;
7298 struct tcp_bbr *bbr;
7299 struct bbr_sendmap *rsm;
7300 struct sackblk sack, sack_blocks[TCP_MAX_SACK + 1];
7301 register uint32_t th_ack;
7302 int32_t i, j, k, new_sb, num_sack_blks = 0;
7303 uint32_t cts, acked, ack_point, sack_changed = 0;
7304 uint32_t p_maxseg, maxseg, p_acked = 0;
7305
7306 INP_WLOCK_ASSERT(tptoinpcb(tp));
7307 if (tcp_get_flags(th) & TH_RST) {
7308 /* We don't log resets */
7309 return (0);
7310 }
7311 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
7312 cts = bbr->r_ctl.rc_rcvtime;
7313
7314 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map);
7315 changed = 0;
7316 maxseg = tp->t_maxseg - bbr->rc_last_options;
7317 p_maxseg = min(bbr->r_ctl.rc_pace_max_segs, maxseg);
7318 th_ack = th->th_ack;
7319 if (SEQ_GT(th_ack, tp->snd_una)) {
7320 acked = th_ack - tp->snd_una;
7321 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_UPDATE, __LINE__);
7322 bbr->rc_tp->t_acktime = ticks;
7323 } else
7324 acked = 0;
7325 if (SEQ_LEQ(th_ack, tp->snd_una)) {
7326 /* Only sent here for sack processing */
7327 goto proc_sack;
7328 }
7329 if (rsm && SEQ_GT(th_ack, rsm->r_start)) {
7330 changed = th_ack - rsm->r_start;
7331 } else if ((rsm == NULL) && ((th_ack - 1) == tp->iss)) {
7332 /*
7333 * For the SYN incoming case we will not have called
7334 * tcp_output for the sending of the SYN, so there will be
7335 * no map. All other cases should probably be a panic.
7336 */
7337 if ((to->to_flags & TOF_TS) && (to->to_tsecr != 0)) {
7338 /*
7339 * We have a timestamp that can be used to generate
7340 * an initial RTT.
7341 */
7342 uint32_t ts, now, rtt;
7343
7344 ts = bbr_ts_convert(to->to_tsecr);
7345 now = bbr_ts_convert(tcp_tv_to_mssectick(&bbr->rc_tv));
7346 rtt = now - ts;
7347 if (rtt < 1)
7348 rtt = 1;
7349 bbr_log_type_bbrrttprop(bbr, rtt,
7350 tp->iss, 0, cts,
7351 BBR_RTT_BY_TIMESTAMP, tp->iss, 0);
7352 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts);
7353 changed = 1;
7354 bbr->r_wanted_output = 1;
7355 goto out;
7356 }
7357 goto proc_sack;
7358 } else if (rsm == NULL) {
7359 goto out;
7360 }
7361 if (changed) {
7362 /*
7363 * The ACK point is advancing to th_ack, we must drop off
7364 * the packets in the rack log and calculate any eligble
7365 * RTT's.
7366 */
7367 bbr->r_wanted_output = 1;
7368 more:
7369 if (rsm == NULL) {
7370 if (tp->t_flags & TF_SENTFIN) {
7371 /* if we send a FIN we will not hav a map */
7372 goto proc_sack;
7373 }
7374 #ifdef BBR_INVARIANTS
7375 panic("No rack map tp:%p for th:%p state:%d bbr:%p snd_una:%u snd_max:%u chg:%d\n",
7376 tp,
7377 th, tp->t_state, bbr,
7378 tp->snd_una, tp->snd_max, changed);
7379 #endif
7380 goto proc_sack;
7381 }
7382 }
7383 if (SEQ_LT(th_ack, rsm->r_start)) {
7384 /* Huh map is missing this */
7385 #ifdef BBR_INVARIANTS
7386 printf("Rack map starts at r_start:%u for th_ack:%u huh? ts:%d rs:%d bbr:%p\n",
7387 rsm->r_start,
7388 th_ack, tp->t_state,
7389 bbr->r_state, bbr);
7390 panic("th-ack is bad bbr:%p tp:%p", bbr, tp);
7391 #endif
7392 goto proc_sack;
7393 } else if (th_ack == rsm->r_start) {
7394 /* None here to ack */
7395 goto proc_sack;
7396 }
7397 /*
7398 * Clear the dup ack counter, it will
7399 * either be freed or if there is some
7400 * remaining we need to start it at zero.
7401 */
7402 rsm->r_dupack = 0;
7403 /* Now do we consume the whole thing? */
7404 if (SEQ_GEQ(th_ack, rsm->r_end)) {
7405 /* Its all consumed. */
7406 uint32_t left;
7407
7408 if (rsm->r_flags & BBR_ACKED) {
7409 /*
7410 * It was acked on the scoreboard -- remove it from
7411 * total
7412 */
7413 p_acked += (rsm->r_end - rsm->r_start);
7414 bbr->r_ctl.rc_sacked -= (rsm->r_end - rsm->r_start);
7415 if (bbr->r_ctl.rc_sacked == 0)
7416 bbr->r_ctl.rc_sacklast = NULL;
7417 } else {
7418 bbr_update_rtt(tp, bbr, rsm, to, cts, BBR_CUM_ACKED, th_ack);
7419 if (rsm->r_flags & BBR_MARKED_LOST) {
7420 bbr->r_ctl.rc_lost_bytes -= rsm->r_end - rsm->r_start;
7421 }
7422 if (rsm->r_flags & BBR_SACK_PASSED) {
7423 /*
7424 * There are acked segments ACKED on the
7425 * scoreboard further up. We are seeing
7426 * reordering.
7427 */
7428 BBR_STAT_INC(bbr_reorder_seen);
7429 bbr->r_ctl.rc_reorder_ts = cts;
7430 if (rsm->r_flags & BBR_MARKED_LOST) {
7431 bbr->r_ctl.rc_lost -= rsm->r_end - rsm->r_start;
7432 if (SEQ_GT(bbr->r_ctl.rc_lt_lost, bbr->r_ctl.rc_lost))
7433 /* LT sampling also needs adjustment */
7434 bbr->r_ctl.rc_lt_lost = bbr->r_ctl.rc_lost;
7435 }
7436 }
7437 rsm->r_flags &= ~BBR_MARKED_LOST;
7438 }
7439 bbr->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes;
7440 rsm->r_rtr_bytes = 0;
7441 TAILQ_REMOVE(&bbr->r_ctl.rc_map, rsm, r_next);
7442 if (rsm->r_in_tmap) {
7443 TAILQ_REMOVE(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
7444 rsm->r_in_tmap = 0;
7445 }
7446 if (bbr->r_ctl.rc_next == rsm) {
7447 /* scoot along the marker */
7448 bbr->r_ctl.rc_next = TAILQ_FIRST(&bbr->r_ctl.rc_map);
7449 }
7450 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_CUM_ACKED);
7451 /* Adjust the packet counts */
7452 left = th_ack - rsm->r_end;
7453 /* Free back to zone */
7454 bbr_free(bbr, rsm);
7455 if (left) {
7456 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map);
7457 goto more;
7458 }
7459 goto proc_sack;
7460 }
7461 if (rsm->r_flags & BBR_ACKED) {
7462 /*
7463 * It was acked on the scoreboard -- remove it from total
7464 * for the part being cum-acked.
7465 */
7466 p_acked += (rsm->r_end - rsm->r_start);
7467 bbr->r_ctl.rc_sacked -= (th_ack - rsm->r_start);
7468 if (bbr->r_ctl.rc_sacked == 0)
7469 bbr->r_ctl.rc_sacklast = NULL;
7470 } else {
7471 /*
7472 * It was acked up to th_ack point for the first time
7473 */
7474 struct bbr_sendmap lrsm;
7475
7476 memcpy(&lrsm, rsm, sizeof(struct bbr_sendmap));
7477 lrsm.r_end = th_ack;
7478 bbr_update_rtt(tp, bbr, &lrsm, to, cts, BBR_CUM_ACKED, th_ack);
7479 }
7480 if ((rsm->r_flags & BBR_MARKED_LOST) &&
7481 ((rsm->r_flags & BBR_ACKED) == 0)) {
7482 /*
7483 * It was marked lost and partly ack'd now
7484 * for the first time. We lower the rc_lost_bytes
7485 * and still leave it MARKED.
7486 */
7487 bbr->r_ctl.rc_lost_bytes -= th_ack - rsm->r_start;
7488 }
7489 bbr_isit_a_pkt_epoch(bbr, cts, rsm, __LINE__, BBR_CUM_ACKED);
7490 bbr->r_ctl.rc_holes_rxt -= rsm->r_rtr_bytes;
7491 rsm->r_rtr_bytes = 0;
7492 /* adjust packet count */
7493 rsm->r_start = th_ack;
7494 proc_sack:
7495 /* Check for reneging */
7496 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map);
7497 if (rsm && (rsm->r_flags & BBR_ACKED) && (th_ack == rsm->r_start)) {
7498 /*
7499 * The peer has moved snd_una up to the edge of this send,
7500 * i.e. one that it had previously acked. The only way that
7501 * can be true if the peer threw away data (space issues)
7502 * that it had previously sacked (else it would have given
7503 * us snd_una up to (rsm->r_end). We need to undo the acked
7504 * markings here.
7505 *
7506 * Note we have to look to make sure th_ack is our
7507 * rsm->r_start in case we get an old ack where th_ack is
7508 * behind snd_una.
7509 */
7510 bbr_peer_reneges(bbr, rsm, th->th_ack);
7511 }
7512 if ((to->to_flags & TOF_SACK) == 0) {
7513 /* We are done nothing left to log */
7514 goto out;
7515 }
7516 rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_map, bbr_sendmap, r_next);
7517 if (rsm) {
7518 last_seq = rsm->r_end;
7519 } else {
7520 last_seq = tp->snd_max;
7521 }
7522 /* Sack block processing */
7523 if (SEQ_GT(th_ack, tp->snd_una))
7524 ack_point = th_ack;
7525 else
7526 ack_point = tp->snd_una;
7527 for (i = 0; i < to->to_nsacks; i++) {
7528 bcopy((to->to_sacks + i * TCPOLEN_SACK),
7529 &sack, sizeof(sack));
7530 sack.start = ntohl(sack.start);
7531 sack.end = ntohl(sack.end);
7532 if (SEQ_GT(sack.end, sack.start) &&
7533 SEQ_GT(sack.start, ack_point) &&
7534 SEQ_LT(sack.start, tp->snd_max) &&
7535 SEQ_GT(sack.end, ack_point) &&
7536 SEQ_LEQ(sack.end, tp->snd_max)) {
7537 if ((bbr->r_ctl.rc_num_small_maps_alloced > bbr_sack_block_limit) &&
7538 (SEQ_LT(sack.end, last_seq)) &&
7539 ((sack.end - sack.start) < (p_maxseg / 8))) {
7540 /*
7541 * Not the last piece and its smaller than
7542 * 1/8th of a p_maxseg. We ignore this.
7543 */
7544 BBR_STAT_INC(bbr_runt_sacks);
7545 continue;
7546 }
7547 sack_blocks[num_sack_blks] = sack;
7548 num_sack_blks++;
7549 } else if (SEQ_LEQ(sack.start, th_ack) &&
7550 SEQ_LEQ(sack.end, th_ack)) {
7551 /*
7552 * Its a D-SACK block.
7553 */
7554 tcp_record_dsack(tp, sack.start, sack.end, 0);
7555 }
7556 }
7557 if (num_sack_blks == 0)
7558 goto out;
7559 /*
7560 * Sort the SACK blocks so we can update the rack scoreboard with
7561 * just one pass.
7562 */
7563 new_sb = sack_filter_blks(&bbr->r_ctl.bbr_sf, sack_blocks,
7564 num_sack_blks, th->th_ack);
7565 ctf_log_sack_filter(bbr->rc_tp, new_sb, sack_blocks);
7566 BBR_STAT_ADD(bbr_sack_blocks, num_sack_blks);
7567 BBR_STAT_ADD(bbr_sack_blocks_skip, (num_sack_blks - new_sb));
7568 num_sack_blks = new_sb;
7569 if (num_sack_blks < 2) {
7570 goto do_sack_work;
7571 }
7572 /* Sort the sacks */
7573 for (i = 0; i < num_sack_blks; i++) {
7574 for (j = i + 1; j < num_sack_blks; j++) {
7575 if (SEQ_GT(sack_blocks[i].end, sack_blocks[j].end)) {
7576 sack = sack_blocks[i];
7577 sack_blocks[i] = sack_blocks[j];
7578 sack_blocks[j] = sack;
7579 }
7580 }
7581 }
7582 /*
7583 * Now are any of the sack block ends the same (yes some
7584 * implememtations send these)?
7585 */
7586 again:
7587 if (num_sack_blks > 1) {
7588 for (i = 0; i < num_sack_blks; i++) {
7589 for (j = i + 1; j < num_sack_blks; j++) {
7590 if (sack_blocks[i].end == sack_blocks[j].end) {
7591 /*
7592 * Ok these two have the same end we
7593 * want the smallest end and then
7594 * throw away the larger and start
7595 * again.
7596 */
7597 if (SEQ_LT(sack_blocks[j].start, sack_blocks[i].start)) {
7598 /*
7599 * The second block covers
7600 * more area use that
7601 */
7602 sack_blocks[i].start = sack_blocks[j].start;
7603 }
7604 /*
7605 * Now collapse out the dup-sack and
7606 * lower the count
7607 */
7608 for (k = (j + 1); k < num_sack_blks; k++) {
7609 sack_blocks[j].start = sack_blocks[k].start;
7610 sack_blocks[j].end = sack_blocks[k].end;
7611 j++;
7612 }
7613 num_sack_blks--;
7614 goto again;
7615 }
7616 }
7617 }
7618 }
7619 do_sack_work:
7620 rsm = bbr->r_ctl.rc_sacklast;
7621 for (i = 0; i < num_sack_blks; i++) {
7622 acked = bbr_proc_sack_blk(tp, bbr, &sack_blocks[i], to, &rsm, cts);
7623 if (acked) {
7624 bbr->r_wanted_output = 1;
7625 changed += acked;
7626 sack_changed += acked;
7627 }
7628 }
7629 out:
7630 *prev_acked = p_acked;
7631 if ((sack_changed) && (!IN_RECOVERY(tp->t_flags))) {
7632 /*
7633 * Ok we have a high probability that we need to go in to
7634 * recovery since we have data sack'd
7635 */
7636 struct bbr_sendmap *rsm;
7637
7638 rsm = bbr_check_recovery_mode(tp, bbr, cts);
7639 if (rsm) {
7640 /* Enter recovery */
7641 entered_recovery = 1;
7642 bbr->r_wanted_output = 1;
7643 /*
7644 * When we enter recovery we need to assure we send
7645 * one packet.
7646 */
7647 if (bbr->r_ctl.rc_resend == NULL) {
7648 bbr->r_ctl.rc_resend = rsm;
7649 }
7650 }
7651 }
7652 if (IN_RECOVERY(tp->t_flags) && (entered_recovery == 0)) {
7653 /*
7654 * See if we need to rack-retransmit anything if so set it
7655 * up as the thing to resend assuming something else is not
7656 * already in that position.
7657 */
7658 if (bbr->r_ctl.rc_resend == NULL) {
7659 bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts);
7660 }
7661 }
7662 /*
7663 * We return the amount that changed via sack, this is used by the
7664 * ack-received code to augment what was changed between th_ack <->
7665 * snd_una.
7666 */
7667 return (sack_changed);
7668 }
7669
7670 static void
7671 bbr_strike_dupack(struct tcp_bbr *bbr)
7672 {
7673 struct bbr_sendmap *rsm;
7674
7675 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_tmap);
7676 if (rsm && (rsm->r_dupack < 0xff)) {
7677 rsm->r_dupack++;
7678 if (rsm->r_dupack >= DUP_ACK_THRESHOLD)
7679 bbr->r_wanted_output = 1;
7680 }
7681 }
7682
7683 /*
7684 * Return value of 1, we do not need to call bbr_process_data().
7685 * return value of 0, bbr_process_data can be called.
7686 * For ret_val if its 0 the TCB is locked and valid, if its non-zero
7687 * its unlocked and probably unsafe to touch the TCB.
7688 */
7689 static int
7690 bbr_process_ack(struct mbuf *m, struct tcphdr *th, struct socket *so,
7691 struct tcpcb *tp, struct tcpopt *to,
7692 uint32_t tiwin, int32_t tlen,
7693 int32_t * ofia, int32_t thflags, int32_t * ret_val)
7694 {
7695 int32_t ourfinisacked = 0;
7696 int32_t acked_amount;
7697 uint16_t nsegs;
7698 int32_t acked;
7699 uint32_t lost, sack_changed = 0;
7700 struct mbuf *mfree;
7701 struct tcp_bbr *bbr;
7702 uint32_t prev_acked = 0;
7703
7704 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
7705 lost = bbr->r_ctl.rc_lost;
7706 nsegs = max(1, m->m_pkthdr.lro_nsegs);
7707 if (SEQ_GT(th->th_ack, tp->snd_max)) {
7708 ctf_do_dropafterack(m, tp, th, thflags, tlen, ret_val);
7709 bbr->r_wanted_output = 1;
7710 return (1);
7711 }
7712 if (SEQ_GEQ(th->th_ack, tp->snd_una) || to->to_nsacks) {
7713 /* Process the ack */
7714 if (bbr->rc_in_persist)
7715 tp->t_rxtshift = 0;
7716 if ((th->th_ack == tp->snd_una) && (tiwin == tp->snd_wnd))
7717 bbr_strike_dupack(bbr);
7718 sack_changed = bbr_log_ack(tp, to, th, &prev_acked);
7719 }
7720 bbr_lt_bw_sampling(bbr, bbr->r_ctl.rc_rcvtime, (bbr->r_ctl.rc_lost > lost));
7721 if (__predict_false(SEQ_LEQ(th->th_ack, tp->snd_una))) {
7722 /*
7723 * Old ack, behind the last one rcv'd or a duplicate ack
7724 * with SACK info.
7725 */
7726 if (th->th_ack == tp->snd_una) {
7727 bbr_ack_received(tp, bbr, th, 0, sack_changed, prev_acked, __LINE__, 0);
7728 if (bbr->r_state == TCPS_SYN_SENT) {
7729 /*
7730 * Special case on where we sent SYN. When
7731 * the SYN-ACK is processed in syn_sent
7732 * state it bumps the snd_una. This causes
7733 * us to hit here even though we did ack 1
7734 * byte.
7735 *
7736 * Go through the nothing left case so we
7737 * send data.
7738 */
7739 goto nothing_left;
7740 }
7741 }
7742 return (0);
7743 }
7744 /*
7745 * If we reach this point, ACK is not a duplicate, i.e., it ACKs
7746 * something we sent.
7747 */
7748 if (tp->t_flags & TF_NEEDSYN) {
7749 /*
7750 * T/TCP: Connection was half-synchronized, and our SYN has
7751 * been ACK'd (so connection is now fully synchronized). Go
7752 * to non-starred state, increment snd_una for ACK of SYN,
7753 * and check if we can do window scaling.
7754 */
7755 tp->t_flags &= ~TF_NEEDSYN;
7756 tp->snd_una++;
7757 /* Do window scaling? */
7758 if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) ==
7759 (TF_RCVD_SCALE | TF_REQ_SCALE)) {
7760 tp->rcv_scale = tp->request_r_scale;
7761 /* Send window already scaled. */
7762 }
7763 }
7764 INP_WLOCK_ASSERT(tptoinpcb(tp));
7765
7766 acked = BYTES_THIS_ACK(tp, th);
7767 KMOD_TCPSTAT_ADD(tcps_rcvackpack, (int)nsegs);
7768 KMOD_TCPSTAT_ADD(tcps_rcvackbyte, acked);
7769
7770 /*
7771 * If we just performed our first retransmit, and the ACK arrives
7772 * within our recovery window, then it was a mistake to do the
7773 * retransmit in the first place. Recover our original cwnd and
7774 * ssthresh, and proceed to transmit where we left off.
7775 */
7776 if (tp->t_flags & TF_PREVVALID) {
7777 tp->t_flags &= ~TF_PREVVALID;
7778 if (tp->t_rxtshift == 1 &&
7779 (int)(ticks - tp->t_badrxtwin) < 0)
7780 bbr_cong_signal(tp, th, CC_RTO_ERR, NULL);
7781 }
7782 SOCKBUF_LOCK(&so->so_snd);
7783 acked_amount = min(acked, (int)sbavail(&so->so_snd));
7784 tp->snd_wnd -= acked_amount;
7785 mfree = sbcut_locked(&so->so_snd, acked_amount);
7786 /* NB: sowwakeup_locked() does an implicit unlock. */
7787 sowwakeup_locked(so);
7788 m_freem(mfree);
7789 if (SEQ_GT(th->th_ack, tp->snd_una)) {
7790 bbr_collapse_rtt(tp, bbr, TCP_REXMTVAL(tp));
7791 }
7792 tp->snd_una = th->th_ack;
7793 bbr_ack_received(tp, bbr, th, acked, sack_changed, prev_acked, __LINE__, (bbr->r_ctl.rc_lost - lost));
7794 if (IN_RECOVERY(tp->t_flags)) {
7795 if (SEQ_LT(th->th_ack, tp->snd_recover) &&
7796 (SEQ_LT(th->th_ack, tp->snd_max))) {
7797 tcp_bbr_partialack(tp);
7798 } else {
7799 bbr_post_recovery(tp);
7800 }
7801 }
7802 if (SEQ_GT(tp->snd_una, tp->snd_recover)) {
7803 tp->snd_recover = tp->snd_una;
7804 }
7805 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) {
7806 tp->snd_nxt = tp->snd_max;
7807 }
7808 if (tp->snd_una == tp->snd_max) {
7809 /* Nothing left outstanding */
7810 nothing_left:
7811 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_CLEAR, __LINE__);
7812 if (sbavail(&so->so_snd) == 0)
7813 bbr->rc_tp->t_acktime = 0;
7814 if ((sbused(&so->so_snd) == 0) &&
7815 (tp->t_flags & TF_SENTFIN)) {
7816 ourfinisacked = 1;
7817 }
7818 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime);
7819 if (bbr->rc_in_persist == 0) {
7820 bbr->r_ctl.rc_went_idle_time = bbr->r_ctl.rc_rcvtime;
7821 }
7822 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una);
7823 bbr_log_ack_clear(bbr, bbr->r_ctl.rc_rcvtime);
7824 /*
7825 * We invalidate the last ack here since we
7826 * don't want to transfer forward the time
7827 * for our sum's calculations.
7828 */
7829 if ((tp->t_state >= TCPS_FIN_WAIT_1) &&
7830 (sbavail(&so->so_snd) == 0) &&
7831 (tp->t_flags2 & TF2_DROP_AF_DATA)) {
7832 /*
7833 * The socket was gone and the peer sent data, time
7834 * to reset him.
7835 */
7836 *ret_val = 1;
7837 tcp_log_end_status(tp, TCP_EI_STATUS_DATA_A_CLOSE);
7838 /* tcp_close will kill the inp pre-log the Reset */
7839 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST);
7840 tp = tcp_close(tp);
7841 ctf_do_dropwithreset(m, tp, th, BANDLIM_UNLIMITED, tlen);
7842 BBR_STAT_INC(bbr_dropped_af_data);
7843 return (1);
7844 }
7845 /* Set need output so persist might get set */
7846 bbr->r_wanted_output = 1;
7847 }
7848 if (ofia)
7849 *ofia = ourfinisacked;
7850 return (0);
7851 }
7852
7853 static void
7854 bbr_enter_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, int32_t line)
7855 {
7856 if (bbr->rc_in_persist == 0) {
7857 bbr_timer_cancel(bbr, __LINE__, cts);
7858 bbr->r_ctl.rc_last_delay_val = 0;
7859 tp->t_rxtshift = 0;
7860 bbr->rc_in_persist = 1;
7861 bbr->r_ctl.rc_went_idle_time = cts;
7862 /* We should be capped when rw went to 0 but just in case */
7863 bbr_log_type_pesist(bbr, cts, 0, line, 1);
7864 /* Time freezes for the state, so do the accounting now */
7865 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) {
7866 uint32_t time_in;
7867
7868 time_in = cts - bbr->r_ctl.rc_bbr_state_time;
7869 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) {
7870 int32_t idx;
7871
7872 idx = bbr_state_val(bbr);
7873 counter_u64_add(bbr_state_time[(idx + 5)], time_in);
7874 } else {
7875 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in);
7876 }
7877 }
7878 bbr->r_ctl.rc_bbr_state_time = cts;
7879 }
7880 }
7881
7882 static void
7883 bbr_restart_after_idle(struct tcp_bbr *bbr, uint32_t cts, uint32_t idle_time)
7884 {
7885 /*
7886 * Note that if idle time does not exceed our
7887 * threshold, we do nothing continuing the state
7888 * transitions we were last walking through.
7889 */
7890 if (idle_time >= bbr_idle_restart_threshold) {
7891 if (bbr->rc_use_idle_restart) {
7892 bbr->rc_bbr_state = BBR_STATE_IDLE_EXIT;
7893 /*
7894 * Set our target using BBR_UNIT, so
7895 * we increase at a dramatic rate but
7896 * we stop when we get the pipe
7897 * full again for our current b/w estimate.
7898 */
7899 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT;
7900 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT;
7901 bbr_set_state_target(bbr, __LINE__);
7902 /* Now setup our gains to ramp up */
7903 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_startup_pg;
7904 bbr->r_ctl.rc_bbr_cwnd_gain = bbr->r_ctl.rc_startup_pg;
7905 bbr_log_type_statechange(bbr, cts, __LINE__);
7906 } else if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) {
7907 bbr_substate_change(bbr, cts, __LINE__, 1);
7908 }
7909 }
7910 }
7911
7912 static void
7913 bbr_exit_persist(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts, int32_t line)
7914 {
7915 uint32_t idle_time;
7916
7917 if (bbr->rc_in_persist == 0)
7918 return;
7919 idle_time = bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time);
7920 bbr->rc_in_persist = 0;
7921 bbr->rc_hit_state_1 = 0;
7922 bbr->r_ctl.rc_del_time = cts;
7923 /*
7924 * We invalidate the last ack here since we
7925 * don't want to transfer forward the time
7926 * for our sum's calculations.
7927 */
7928 if (tcp_in_hpts(bbr->rc_inp)) {
7929 tcp_hpts_remove(bbr->rc_inp);
7930 bbr->rc_timer_first = 0;
7931 bbr->r_ctl.rc_hpts_flags = 0;
7932 bbr->r_ctl.rc_last_delay_val = 0;
7933 bbr->r_ctl.rc_hptsi_agg_delay = 0;
7934 bbr->r_agg_early_set = 0;
7935 bbr->r_ctl.rc_agg_early = 0;
7936 }
7937 bbr_log_type_pesist(bbr, cts, idle_time, line, 0);
7938 if (idle_time >= bbr_rtt_probe_time) {
7939 /*
7940 * This qualifies as a RTT_PROBE session since we drop the
7941 * data outstanding to nothing and waited more than
7942 * bbr_rtt_probe_time.
7943 */
7944 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_PERSIST, 0);
7945 bbr->r_ctl.last_in_probertt = bbr->r_ctl.rc_rtt_shrinks = cts;
7946 }
7947 tp->t_rxtshift = 0;
7948 /*
7949 * If in probeBW and we have persisted more than an RTT lets do
7950 * special handling.
7951 */
7952 /* Force a time based epoch */
7953 bbr_set_epoch(bbr, cts, __LINE__);
7954 /*
7955 * Setup the lost so we don't count anything against the guy
7956 * we have been stuck with during persists.
7957 */
7958 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost;
7959 /* Time un-freezes for the state */
7960 bbr->r_ctl.rc_bbr_state_time = cts;
7961 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_BW) ||
7962 (bbr->rc_bbr_state == BBR_STATE_PROBE_RTT)) {
7963 /*
7964 * If we are going back to probe-bw
7965 * or probe_rtt, we may need to possibly
7966 * do a fast restart.
7967 */
7968 bbr_restart_after_idle(bbr, cts, idle_time);
7969 }
7970 }
7971
7972 static void
7973 bbr_collapsed_window(struct tcp_bbr *bbr)
7974 {
7975 /*
7976 * Now we must walk the
7977 * send map and divide the
7978 * ones left stranded. These
7979 * guys can't cause us to abort
7980 * the connection and are really
7981 * "unsent". However if a buggy
7982 * client actually did keep some
7983 * of the data i.e. collapsed the win
7984 * and refused to ack and then opened
7985 * the win and acked that data. We would
7986 * get into an ack war, the simplier
7987 * method then of just pretending we
7988 * did not send those segments something
7989 * won't work.
7990 */
7991 struct bbr_sendmap *rsm, *nrsm;
7992 tcp_seq max_seq;
7993 uint32_t maxseg;
7994 int can_split = 0;
7995 int fnd = 0;
7996
7997 maxseg = bbr->rc_tp->t_maxseg - bbr->rc_last_options;
7998 max_seq = bbr->rc_tp->snd_una + bbr->rc_tp->snd_wnd;
7999 bbr_log_type_rwnd_collapse(bbr, max_seq, 1, 0);
8000 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) {
8001 /* Find the first seq past or at maxseq */
8002 if (rsm->r_flags & BBR_RWND_COLLAPSED)
8003 rsm->r_flags &= ~BBR_RWND_COLLAPSED;
8004 if (SEQ_GEQ(max_seq, rsm->r_start) &&
8005 SEQ_GEQ(rsm->r_end, max_seq)) {
8006 fnd = 1;
8007 break;
8008 }
8009 }
8010 bbr->rc_has_collapsed = 0;
8011 if (!fnd) {
8012 /* Nothing to do strange */
8013 return;
8014 }
8015 /*
8016 * Now can we split?
8017 *
8018 * We don't want to split if splitting
8019 * would generate too many small segments
8020 * less we let an attacker fragment our
8021 * send_map and leave us out of memory.
8022 */
8023 if ((max_seq != rsm->r_start) &&
8024 (max_seq != rsm->r_end)){
8025 /* can we split? */
8026 int res1, res2;
8027
8028 res1 = max_seq - rsm->r_start;
8029 res2 = rsm->r_end - max_seq;
8030 if ((res1 >= (maxseg/8)) &&
8031 (res2 >= (maxseg/8))) {
8032 /* No small pieces here */
8033 can_split = 1;
8034 } else if (bbr->r_ctl.rc_num_small_maps_alloced < bbr_sack_block_limit) {
8035 /* We are under the limit */
8036 can_split = 1;
8037 }
8038 }
8039 /* Ok do we need to split this rsm? */
8040 if (max_seq == rsm->r_start) {
8041 /* It's this guy no split required */
8042 nrsm = rsm;
8043 } else if (max_seq == rsm->r_end) {
8044 /* It's the next one no split required. */
8045 nrsm = TAILQ_NEXT(rsm, r_next);
8046 if (nrsm == NULL) {
8047 /* Huh? */
8048 return;
8049 }
8050 } else if (can_split && SEQ_LT(max_seq, rsm->r_end)) {
8051 /* yep we need to split it */
8052 nrsm = bbr_alloc_limit(bbr, BBR_LIMIT_TYPE_SPLIT);
8053 if (nrsm == NULL) {
8054 /* failed XXXrrs what can we do mark the whole? */
8055 nrsm = rsm;
8056 goto no_split;
8057 }
8058 /* Clone it */
8059 bbr_log_type_rwnd_collapse(bbr, max_seq, 3, 0);
8060 bbr_clone_rsm(bbr, nrsm, rsm, max_seq);
8061 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_map, rsm, nrsm, r_next);
8062 if (rsm->r_in_tmap) {
8063 TAILQ_INSERT_AFTER(&bbr->r_ctl.rc_tmap, rsm, nrsm, r_tnext);
8064 nrsm->r_in_tmap = 1;
8065 }
8066 } else {
8067 /*
8068 * Split not allowed just start here just
8069 * use this guy.
8070 */
8071 nrsm = rsm;
8072 }
8073 no_split:
8074 BBR_STAT_INC(bbr_collapsed_win);
8075 /* reuse fnd as a count */
8076 fnd = 0;
8077 TAILQ_FOREACH_FROM(nrsm, &bbr->r_ctl.rc_map, r_next) {
8078 nrsm->r_flags |= BBR_RWND_COLLAPSED;
8079 fnd++;
8080 bbr->rc_has_collapsed = 1;
8081 }
8082 bbr_log_type_rwnd_collapse(bbr, max_seq, 4, fnd);
8083 }
8084
8085 static void
8086 bbr_un_collapse_window(struct tcp_bbr *bbr)
8087 {
8088 struct bbr_sendmap *rsm;
8089 int cleared = 0;
8090
8091 TAILQ_FOREACH_REVERSE(rsm, &bbr->r_ctl.rc_map, bbr_head, r_next) {
8092 if (rsm->r_flags & BBR_RWND_COLLAPSED) {
8093 /* Clear the flag */
8094 rsm->r_flags &= ~BBR_RWND_COLLAPSED;
8095 cleared++;
8096 } else
8097 break;
8098 }
8099 bbr_log_type_rwnd_collapse(bbr,
8100 (bbr->rc_tp->snd_una + bbr->rc_tp->snd_wnd), 0, cleared);
8101 bbr->rc_has_collapsed = 0;
8102 }
8103
8104 /*
8105 * Return value of 1, the TCB is unlocked and most
8106 * likely gone, return value of 0, the TCB is still
8107 * locked.
8108 */
8109 static int
8110 bbr_process_data(struct mbuf *m, struct tcphdr *th, struct socket *so,
8111 struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen,
8112 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt)
8113 {
8114 /*
8115 * Update window information. Don't look at window if no ACK: TAC's
8116 * send garbage on first SYN.
8117 */
8118 uint16_t nsegs;
8119 int32_t tfo_syn;
8120 struct tcp_bbr *bbr;
8121
8122 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
8123 INP_WLOCK_ASSERT(tptoinpcb(tp));
8124 nsegs = max(1, m->m_pkthdr.lro_nsegs);
8125 if ((thflags & TH_ACK) &&
8126 (SEQ_LT(tp->snd_wl1, th->th_seq) ||
8127 (tp->snd_wl1 == th->th_seq && (SEQ_LT(tp->snd_wl2, th->th_ack) ||
8128 (tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd))))) {
8129 /* keep track of pure window updates */
8130 if (tlen == 0 &&
8131 tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd)
8132 KMOD_TCPSTAT_INC(tcps_rcvwinupd);
8133 tp->snd_wnd = tiwin;
8134 tp->snd_wl1 = th->th_seq;
8135 tp->snd_wl2 = th->th_ack;
8136 if (tp->snd_wnd > tp->max_sndwnd)
8137 tp->max_sndwnd = tp->snd_wnd;
8138 bbr->r_wanted_output = 1;
8139 } else if (thflags & TH_ACK) {
8140 if ((tp->snd_wl2 == th->th_ack) && (tiwin < tp->snd_wnd)) {
8141 tp->snd_wnd = tiwin;
8142 tp->snd_wl1 = th->th_seq;
8143 tp->snd_wl2 = th->th_ack;
8144 }
8145 }
8146 if (tp->snd_wnd < ctf_outstanding(tp))
8147 /* The peer collapsed its window on us */
8148 bbr_collapsed_window(bbr);
8149 else if (bbr->rc_has_collapsed)
8150 bbr_un_collapse_window(bbr);
8151 /* Was persist timer active and now we have window space? */
8152 if ((bbr->rc_in_persist != 0) &&
8153 (tp->snd_wnd >= min((bbr->r_ctl.rc_high_rwnd/2),
8154 bbr_minseg(bbr)))) {
8155 /*
8156 * Make the rate persist at end of persist mode if idle long
8157 * enough
8158 */
8159 bbr_exit_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__);
8160
8161 /* Make sure we output to start the timer */
8162 bbr->r_wanted_output = 1;
8163 }
8164 /* Do we need to enter persist? */
8165 if ((bbr->rc_in_persist == 0) &&
8166 (tp->snd_wnd < min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) &&
8167 TCPS_HAVEESTABLISHED(tp->t_state) &&
8168 (tp->snd_max == tp->snd_una) &&
8169 sbavail(&so->so_snd) &&
8170 (sbavail(&so->so_snd) > tp->snd_wnd)) {
8171 /* No send window.. we must enter persist */
8172 bbr_enter_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__);
8173 }
8174 if (tp->t_flags2 & TF2_DROP_AF_DATA) {
8175 m_freem(m);
8176 return (0);
8177 }
8178 /*
8179 * We don't support urgent data but
8180 * drag along the up just to make sure
8181 * if there is a stack switch no one
8182 * is surprised.
8183 */
8184 tp->rcv_up = tp->rcv_nxt;
8185
8186 /*
8187 * Process the segment text, merging it into the TCP sequencing
8188 * queue, and arranging for acknowledgment of receipt if necessary.
8189 * This process logically involves adjusting tp->rcv_wnd as data is
8190 * presented to the user (this happens in tcp_usrreq.c, case
8191 * PRU_RCVD). If a FIN has already been received on this connection
8192 * then we just ignore the text.
8193 */
8194 tfo_syn = ((tp->t_state == TCPS_SYN_RECEIVED) &&
8195 IS_FASTOPEN(tp->t_flags));
8196 if ((tlen || (thflags & TH_FIN) || (tfo_syn && tlen > 0)) &&
8197 TCPS_HAVERCVDFIN(tp->t_state) == 0) {
8198 tcp_seq save_start = th->th_seq;
8199 tcp_seq save_rnxt = tp->rcv_nxt;
8200 int save_tlen = tlen;
8201
8202 m_adj(m, drop_hdrlen); /* delayed header drop */
8203 /*
8204 * Insert segment which includes th into TCP reassembly
8205 * queue with control block tp. Set thflags to whether
8206 * reassembly now includes a segment with FIN. This handles
8207 * the common case inline (segment is the next to be
8208 * received on an established connection, and the queue is
8209 * empty), avoiding linkage into and removal from the queue
8210 * and repetition of various conversions. Set DELACK for
8211 * segments received in order, but ack immediately when
8212 * segments are out of order (so fast retransmit can work).
8213 */
8214 if (th->th_seq == tp->rcv_nxt &&
8215 SEGQ_EMPTY(tp) &&
8216 (TCPS_HAVEESTABLISHED(tp->t_state) ||
8217 tfo_syn)) {
8218 #ifdef NETFLIX_SB_LIMITS
8219 u_int mcnt, appended;
8220
8221 if (so->so_rcv.sb_shlim) {
8222 mcnt = m_memcnt(m);
8223 appended = 0;
8224 if (counter_fo_get(so->so_rcv.sb_shlim, mcnt,
8225 CFO_NOSLEEP, NULL) == false) {
8226 counter_u64_add(tcp_sb_shlim_fails, 1);
8227 m_freem(m);
8228 return (0);
8229 }
8230 }
8231
8232 #endif
8233 if (DELAY_ACK(tp, bbr, nsegs) || tfo_syn) {
8234 bbr->bbr_segs_rcvd += max(1, nsegs);
8235 tp->t_flags |= TF_DELACK;
8236 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime);
8237 } else {
8238 bbr->r_wanted_output = 1;
8239 tp->t_flags |= TF_ACKNOW;
8240 }
8241 tp->rcv_nxt += tlen;
8242 if (tlen &&
8243 ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) &&
8244 (tp->t_fbyte_in == 0)) {
8245 tp->t_fbyte_in = ticks;
8246 if (tp->t_fbyte_in == 0)
8247 tp->t_fbyte_in = 1;
8248 if (tp->t_fbyte_out && tp->t_fbyte_in)
8249 tp->t_flags2 |= TF2_FBYTES_COMPLETE;
8250 }
8251 thflags = tcp_get_flags(th) & TH_FIN;
8252 KMOD_TCPSTAT_ADD(tcps_rcvpack, (int)nsegs);
8253 KMOD_TCPSTAT_ADD(tcps_rcvbyte, tlen);
8254 SOCKBUF_LOCK(&so->so_rcv);
8255 if (so->so_rcv.sb_state & SBS_CANTRCVMORE)
8256 m_freem(m);
8257 else
8258 #ifdef NETFLIX_SB_LIMITS
8259 appended =
8260 #endif
8261 sbappendstream_locked(&so->so_rcv, m, 0);
8262 /* NB: sorwakeup_locked() does an implicit unlock. */
8263 sorwakeup_locked(so);
8264 #ifdef NETFLIX_SB_LIMITS
8265 if (so->so_rcv.sb_shlim && appended != mcnt)
8266 counter_fo_release(so->so_rcv.sb_shlim,
8267 mcnt - appended);
8268 #endif
8269
8270 } else {
8271 /*
8272 * XXX: Due to the header drop above "th" is
8273 * theoretically invalid by now. Fortunately
8274 * m_adj() doesn't actually frees any mbufs when
8275 * trimming from the head.
8276 */
8277 tcp_seq temp = save_start;
8278
8279 thflags = tcp_reass(tp, th, &temp, &tlen, m);
8280 tp->t_flags |= TF_ACKNOW;
8281 if (tp->t_flags & TF_WAKESOR) {
8282 tp->t_flags &= ~TF_WAKESOR;
8283 /* NB: sorwakeup_locked() does an implicit unlock. */
8284 sorwakeup_locked(so);
8285 }
8286 }
8287 if ((tp->t_flags & TF_SACK_PERMIT) &&
8288 (save_tlen > 0) &&
8289 TCPS_HAVEESTABLISHED(tp->t_state)) {
8290 if ((tlen == 0) && (SEQ_LT(save_start, save_rnxt))) {
8291 /*
8292 * DSACK actually handled in the fastpath
8293 * above.
8294 */
8295 tcp_update_sack_list(tp, save_start,
8296 save_start + save_tlen);
8297 } else if ((tlen > 0) && SEQ_GT(tp->rcv_nxt, save_rnxt)) {
8298 if ((tp->rcv_numsacks >= 1) &&
8299 (tp->sackblks[0].end == save_start)) {
8300 /*
8301 * Partial overlap, recorded at todrop
8302 * above.
8303 */
8304 tcp_update_sack_list(tp,
8305 tp->sackblks[0].start,
8306 tp->sackblks[0].end);
8307 } else {
8308 tcp_update_dsack_list(tp, save_start,
8309 save_start + save_tlen);
8310 }
8311 } else if (tlen >= save_tlen) {
8312 /* Update of sackblks. */
8313 tcp_update_dsack_list(tp, save_start,
8314 save_start + save_tlen);
8315 } else if (tlen > 0) {
8316 tcp_update_dsack_list(tp, save_start,
8317 save_start + tlen);
8318 }
8319 }
8320 } else {
8321 m_freem(m);
8322 thflags &= ~TH_FIN;
8323 }
8324
8325 /*
8326 * If FIN is received ACK the FIN and let the user know that the
8327 * connection is closing.
8328 */
8329 if (thflags & TH_FIN) {
8330 if (TCPS_HAVERCVDFIN(tp->t_state) == 0) {
8331 /* The socket upcall is handled by socantrcvmore. */
8332 socantrcvmore(so);
8333 /*
8334 * If connection is half-synchronized (ie NEEDSYN
8335 * flag on) then delay ACK, so it may be piggybacked
8336 * when SYN is sent. Otherwise, since we received a
8337 * FIN then no more input can be expected, send ACK
8338 * now.
8339 */
8340 if (tp->t_flags & TF_NEEDSYN) {
8341 tp->t_flags |= TF_DELACK;
8342 bbr_timer_cancel(bbr,
8343 __LINE__, bbr->r_ctl.rc_rcvtime);
8344 } else {
8345 tp->t_flags |= TF_ACKNOW;
8346 }
8347 tp->rcv_nxt++;
8348 }
8349 switch (tp->t_state) {
8350 /*
8351 * In SYN_RECEIVED and ESTABLISHED STATES enter the
8352 * CLOSE_WAIT state.
8353 */
8354 case TCPS_SYN_RECEIVED:
8355 tp->t_starttime = ticks;
8356 /* FALLTHROUGH */
8357 case TCPS_ESTABLISHED:
8358 tcp_state_change(tp, TCPS_CLOSE_WAIT);
8359 break;
8360
8361 /*
8362 * If still in FIN_WAIT_1 STATE FIN has not been
8363 * acked so enter the CLOSING state.
8364 */
8365 case TCPS_FIN_WAIT_1:
8366 tcp_state_change(tp, TCPS_CLOSING);
8367 break;
8368
8369 /*
8370 * In FIN_WAIT_2 state enter the TIME_WAIT state,
8371 * starting the time-wait timer, turning off the
8372 * other standard timers.
8373 */
8374 case TCPS_FIN_WAIT_2:
8375 bbr->rc_timer_first = 1;
8376 bbr_timer_cancel(bbr,
8377 __LINE__, bbr->r_ctl.rc_rcvtime);
8378 tcp_twstart(tp);
8379 return (1);
8380 }
8381 }
8382 /*
8383 * Return any desired output.
8384 */
8385 if ((tp->t_flags & TF_ACKNOW) ||
8386 (sbavail(&so->so_snd) > ctf_outstanding(tp))) {
8387 bbr->r_wanted_output = 1;
8388 }
8389 return (0);
8390 }
8391
8392 /*
8393 * Here nothing is really faster, its just that we
8394 * have broken out the fast-data path also just like
8395 * the fast-ack. Return 1 if we processed the packet
8396 * return 0 if you need to take the "slow-path".
8397 */
8398 static int
8399 bbr_do_fastnewdata(struct mbuf *m, struct tcphdr *th, struct socket *so,
8400 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
8401 uint32_t tiwin, int32_t nxt_pkt)
8402 {
8403 uint16_t nsegs;
8404 int32_t newsize = 0; /* automatic sockbuf scaling */
8405 struct tcp_bbr *bbr;
8406 #ifdef NETFLIX_SB_LIMITS
8407 u_int mcnt, appended;
8408 #endif
8409
8410 /* On the hpts and we would have called output */
8411 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
8412
8413 /*
8414 * If last ACK falls within this segment's sequence numbers, record
8415 * the timestamp. NOTE that the test is modified according to the
8416 * latest proposal of the tcplw@cray.com list (Braden 1993/04/26).
8417 */
8418 if (bbr->r_ctl.rc_resend != NULL) {
8419 return (0);
8420 }
8421 if (tiwin && tiwin != tp->snd_wnd) {
8422 return (0);
8423 }
8424 if (__predict_false((tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN)))) {
8425 return (0);
8426 }
8427 if (__predict_false((to->to_flags & TOF_TS) &&
8428 (TSTMP_LT(to->to_tsval, tp->ts_recent)))) {
8429 return (0);
8430 }
8431 if (__predict_false((th->th_ack != tp->snd_una))) {
8432 return (0);
8433 }
8434 if (__predict_false(tlen > sbspace(&so->so_rcv))) {
8435 return (0);
8436 }
8437 if ((to->to_flags & TOF_TS) != 0 &&
8438 SEQ_LEQ(th->th_seq, tp->last_ack_sent)) {
8439 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv);
8440 tp->ts_recent = to->to_tsval;
8441 }
8442 /*
8443 * This is a pure, in-sequence data packet with nothing on the
8444 * reassembly queue and we have enough buffer space to take it.
8445 */
8446 nsegs = max(1, m->m_pkthdr.lro_nsegs);
8447
8448 #ifdef NETFLIX_SB_LIMITS
8449 if (so->so_rcv.sb_shlim) {
8450 mcnt = m_memcnt(m);
8451 appended = 0;
8452 if (counter_fo_get(so->so_rcv.sb_shlim, mcnt,
8453 CFO_NOSLEEP, NULL) == false) {
8454 counter_u64_add(tcp_sb_shlim_fails, 1);
8455 m_freem(m);
8456 return (1);
8457 }
8458 }
8459 #endif
8460 /* Clean receiver SACK report if present */
8461 if (tp->rcv_numsacks)
8462 tcp_clean_sackreport(tp);
8463 KMOD_TCPSTAT_INC(tcps_preddat);
8464 tp->rcv_nxt += tlen;
8465 if (tlen &&
8466 ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) &&
8467 (tp->t_fbyte_in == 0)) {
8468 tp->t_fbyte_in = ticks;
8469 if (tp->t_fbyte_in == 0)
8470 tp->t_fbyte_in = 1;
8471 if (tp->t_fbyte_out && tp->t_fbyte_in)
8472 tp->t_flags2 |= TF2_FBYTES_COMPLETE;
8473 }
8474 /*
8475 * Pull snd_wl1 up to prevent seq wrap relative to th_seq.
8476 */
8477 tp->snd_wl1 = th->th_seq;
8478 /*
8479 * Pull rcv_up up to prevent seq wrap relative to rcv_nxt.
8480 */
8481 tp->rcv_up = tp->rcv_nxt;
8482 KMOD_TCPSTAT_ADD(tcps_rcvpack, (int)nsegs);
8483 KMOD_TCPSTAT_ADD(tcps_rcvbyte, tlen);
8484 newsize = tcp_autorcvbuf(m, th, so, tp, tlen);
8485
8486 /* Add data to socket buffer. */
8487 SOCKBUF_LOCK(&so->so_rcv);
8488 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
8489 m_freem(m);
8490 } else {
8491 /*
8492 * Set new socket buffer size. Give up when limit is
8493 * reached.
8494 */
8495 if (newsize)
8496 if (!sbreserve_locked(so, SO_RCV, newsize, NULL))
8497 so->so_rcv.sb_flags &= ~SB_AUTOSIZE;
8498 m_adj(m, drop_hdrlen); /* delayed header drop */
8499
8500 #ifdef NETFLIX_SB_LIMITS
8501 appended =
8502 #endif
8503 sbappendstream_locked(&so->so_rcv, m, 0);
8504 ctf_calc_rwin(so, tp);
8505 }
8506 /* NB: sorwakeup_locked() does an implicit unlock. */
8507 sorwakeup_locked(so);
8508 #ifdef NETFLIX_SB_LIMITS
8509 if (so->so_rcv.sb_shlim && mcnt != appended)
8510 counter_fo_release(so->so_rcv.sb_shlim, mcnt - appended);
8511 #endif
8512 if (DELAY_ACK(tp, bbr, nsegs)) {
8513 bbr->bbr_segs_rcvd += max(1, nsegs);
8514 tp->t_flags |= TF_DELACK;
8515 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime);
8516 } else {
8517 bbr->r_wanted_output = 1;
8518 tp->t_flags |= TF_ACKNOW;
8519 }
8520 return (1);
8521 }
8522
8523 /*
8524 * This subfunction is used to try to highly optimize the
8525 * fast path. We again allow window updates that are
8526 * in sequence to remain in the fast-path. We also add
8527 * in the __predict's to attempt to help the compiler.
8528 * Note that if we return a 0, then we can *not* process
8529 * it and the caller should push the packet into the
8530 * slow-path. If we return 1, then all is well and
8531 * the packet is fully processed.
8532 */
8533 static int
8534 bbr_fastack(struct mbuf *m, struct tcphdr *th, struct socket *so,
8535 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
8536 uint32_t tiwin, int32_t nxt_pkt, uint8_t iptos)
8537 {
8538 int32_t acked;
8539 uint16_t nsegs;
8540 uint32_t sack_changed;
8541 uint32_t prev_acked = 0;
8542 struct tcp_bbr *bbr;
8543
8544 if (__predict_false(SEQ_LEQ(th->th_ack, tp->snd_una))) {
8545 /* Old ack, behind (or duplicate to) the last one rcv'd */
8546 return (0);
8547 }
8548 if (__predict_false(SEQ_GT(th->th_ack, tp->snd_max))) {
8549 /* Above what we have sent? */
8550 return (0);
8551 }
8552 if (__predict_false(tiwin == 0)) {
8553 /* zero window */
8554 return (0);
8555 }
8556 if (__predict_false(tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN))) {
8557 /* We need a SYN or a FIN, unlikely.. */
8558 return (0);
8559 }
8560 if ((to->to_flags & TOF_TS) && __predict_false(TSTMP_LT(to->to_tsval, tp->ts_recent))) {
8561 /* Timestamp is behind .. old ack with seq wrap? */
8562 return (0);
8563 }
8564 if (__predict_false(IN_RECOVERY(tp->t_flags))) {
8565 /* Still recovering */
8566 return (0);
8567 }
8568 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
8569 if (__predict_false(bbr->r_ctl.rc_resend != NULL)) {
8570 /* We are retransmitting */
8571 return (0);
8572 }
8573 if (__predict_false(bbr->rc_in_persist != 0)) {
8574 /* In persist mode */
8575 return (0);
8576 }
8577 if (bbr->r_ctl.rc_sacked) {
8578 /* We have sack holes on our scoreboard */
8579 return (0);
8580 }
8581 /* Ok if we reach here, we can process a fast-ack */
8582 nsegs = max(1, m->m_pkthdr.lro_nsegs);
8583 sack_changed = bbr_log_ack(tp, to, th, &prev_acked);
8584 /*
8585 * We never detect loss in fast ack [we can't
8586 * have a sack and can't be in recovery so
8587 * we always pass 0 (nothing detected)].
8588 */
8589 bbr_lt_bw_sampling(bbr, bbr->r_ctl.rc_rcvtime, 0);
8590 /* Did the window get updated? */
8591 if (tiwin != tp->snd_wnd) {
8592 tp->snd_wnd = tiwin;
8593 tp->snd_wl1 = th->th_seq;
8594 if (tp->snd_wnd > tp->max_sndwnd)
8595 tp->max_sndwnd = tp->snd_wnd;
8596 }
8597 /* Do we need to exit persists? */
8598 if ((bbr->rc_in_persist != 0) &&
8599 (tp->snd_wnd >= min((bbr->r_ctl.rc_high_rwnd/2),
8600 bbr_minseg(bbr)))) {
8601 bbr_exit_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__);
8602 bbr->r_wanted_output = 1;
8603 }
8604 /* Do we need to enter persists? */
8605 if ((bbr->rc_in_persist == 0) &&
8606 (tp->snd_wnd < min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) &&
8607 TCPS_HAVEESTABLISHED(tp->t_state) &&
8608 (tp->snd_max == tp->snd_una) &&
8609 sbavail(&so->so_snd) &&
8610 (sbavail(&so->so_snd) > tp->snd_wnd)) {
8611 /* No send window.. we must enter persist */
8612 bbr_enter_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__);
8613 }
8614 /*
8615 * If last ACK falls within this segment's sequence numbers, record
8616 * the timestamp. NOTE that the test is modified according to the
8617 * latest proposal of the tcplw@cray.com list (Braden 1993/04/26).
8618 */
8619 if ((to->to_flags & TOF_TS) != 0 &&
8620 SEQ_LEQ(th->th_seq, tp->last_ack_sent)) {
8621 tp->ts_recent_age = bbr->r_ctl.rc_rcvtime;
8622 tp->ts_recent = to->to_tsval;
8623 }
8624 /*
8625 * This is a pure ack for outstanding data.
8626 */
8627 KMOD_TCPSTAT_INC(tcps_predack);
8628
8629 /*
8630 * "bad retransmit" recovery.
8631 */
8632 if (tp->t_flags & TF_PREVVALID) {
8633 tp->t_flags &= ~TF_PREVVALID;
8634 if (tp->t_rxtshift == 1 &&
8635 (int)(ticks - tp->t_badrxtwin) < 0)
8636 bbr_cong_signal(tp, th, CC_RTO_ERR, NULL);
8637 }
8638 /*
8639 * Recalculate the transmit timer / rtt.
8640 *
8641 * Some boxes send broken timestamp replies during the SYN+ACK
8642 * phase, ignore timestamps of 0 or we could calculate a huge RTT
8643 * and blow up the retransmit timer.
8644 */
8645 acked = BYTES_THIS_ACK(tp, th);
8646
8647 #ifdef TCP_HHOOK
8648 /* Run HHOOK_TCP_ESTABLISHED_IN helper hooks. */
8649 hhook_run_tcp_est_in(tp, th, to);
8650 #endif
8651
8652 KMOD_TCPSTAT_ADD(tcps_rcvackpack, (int)nsegs);
8653 KMOD_TCPSTAT_ADD(tcps_rcvackbyte, acked);
8654 sbdrop(&so->so_snd, acked);
8655
8656 if (SEQ_GT(th->th_ack, tp->snd_una))
8657 bbr_collapse_rtt(tp, bbr, TCP_REXMTVAL(tp));
8658 tp->snd_una = th->th_ack;
8659 if (tp->snd_wnd < ctf_outstanding(tp))
8660 /* The peer collapsed its window on us */
8661 bbr_collapsed_window(bbr);
8662 else if (bbr->rc_has_collapsed)
8663 bbr_un_collapse_window(bbr);
8664
8665 if (SEQ_GT(tp->snd_una, tp->snd_recover)) {
8666 tp->snd_recover = tp->snd_una;
8667 }
8668 bbr_ack_received(tp, bbr, th, acked, sack_changed, prev_acked, __LINE__, 0);
8669 /*
8670 * Pull snd_wl2 up to prevent seq wrap relative to th_ack.
8671 */
8672 tp->snd_wl2 = th->th_ack;
8673 m_freem(m);
8674 /*
8675 * If all outstanding data are acked, stop retransmit timer,
8676 * otherwise restart timer using current (possibly backed-off)
8677 * value. If process is waiting for space, wakeup/selwakeup/signal.
8678 * If data are ready to send, let tcp_output decide between more
8679 * output or persist.
8680 * Wake up the socket if we have room to write more.
8681 */
8682 sowwakeup(so);
8683 if (tp->snd_una == tp->snd_max) {
8684 /* Nothing left outstanding */
8685 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_CLEAR, __LINE__);
8686 if (sbavail(&so->so_snd) == 0)
8687 bbr->rc_tp->t_acktime = 0;
8688 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime);
8689 if (bbr->rc_in_persist == 0) {
8690 bbr->r_ctl.rc_went_idle_time = bbr->r_ctl.rc_rcvtime;
8691 }
8692 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una);
8693 bbr_log_ack_clear(bbr, bbr->r_ctl.rc_rcvtime);
8694 /*
8695 * We invalidate the last ack here since we
8696 * don't want to transfer forward the time
8697 * for our sum's calculations.
8698 */
8699 bbr->r_wanted_output = 1;
8700 }
8701 if (sbavail(&so->so_snd)) {
8702 bbr->r_wanted_output = 1;
8703 }
8704 return (1);
8705 }
8706
8707 /*
8708 * Return value of 1, the TCB is unlocked and most
8709 * likely gone, return value of 0, the TCB is still
8710 * locked.
8711 */
8712 static int
8713 bbr_do_syn_sent(struct mbuf *m, struct tcphdr *th, struct socket *so,
8714 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
8715 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos)
8716 {
8717 int32_t todrop;
8718 int32_t ourfinisacked = 0;
8719 struct tcp_bbr *bbr;
8720 int32_t ret_val = 0;
8721
8722 INP_WLOCK_ASSERT(tptoinpcb(tp));
8723
8724 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
8725 ctf_calc_rwin(so, tp);
8726 /*
8727 * If the state is SYN_SENT: if seg contains an ACK, but not for our
8728 * SYN, drop the input. if seg contains a RST, then drop the
8729 * connection. if seg does not contain SYN, then drop it. Otherwise
8730 * this is an acceptable SYN segment initialize tp->rcv_nxt and
8731 * tp->irs if seg contains ack then advance tp->snd_una. BRR does
8732 * not support ECN so we will not say we are capable. if SYN has
8733 * been acked change to ESTABLISHED else SYN_RCVD state arrange for
8734 * segment to be acked (eventually) continue processing rest of
8735 * data/controls, beginning with URG
8736 */
8737 if ((thflags & TH_ACK) &&
8738 (SEQ_LEQ(th->th_ack, tp->iss) ||
8739 SEQ_GT(th->th_ack, tp->snd_max))) {
8740 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT);
8741 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
8742 return (1);
8743 }
8744 if ((thflags & (TH_ACK | TH_RST)) == (TH_ACK | TH_RST)) {
8745 TCP_PROBE5(connect__refused, NULL, tp,
8746 mtod(m, const char *), tp, th);
8747 tp = tcp_drop(tp, ECONNREFUSED);
8748 ctf_do_drop(m, tp);
8749 return (1);
8750 }
8751 if (thflags & TH_RST) {
8752 ctf_do_drop(m, tp);
8753 return (1);
8754 }
8755 if (!(thflags & TH_SYN)) {
8756 ctf_do_drop(m, tp);
8757 return (1);
8758 }
8759 tp->irs = th->th_seq;
8760 tcp_rcvseqinit(tp);
8761 if (thflags & TH_ACK) {
8762 int tfo_partial = 0;
8763
8764 KMOD_TCPSTAT_INC(tcps_connects);
8765 soisconnected(so);
8766 #ifdef MAC
8767 mac_socketpeer_set_from_mbuf(m, so);
8768 #endif
8769 /* Do window scaling on this connection? */
8770 if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) ==
8771 (TF_RCVD_SCALE | TF_REQ_SCALE)) {
8772 tp->rcv_scale = tp->request_r_scale;
8773 }
8774 tp->rcv_adv += min(tp->rcv_wnd,
8775 TCP_MAXWIN << tp->rcv_scale);
8776 /*
8777 * If not all the data that was sent in the TFO SYN
8778 * has been acked, resend the remainder right away.
8779 */
8780 if (IS_FASTOPEN(tp->t_flags) &&
8781 (tp->snd_una != tp->snd_max)) {
8782 tp->snd_nxt = th->th_ack;
8783 tfo_partial = 1;
8784 }
8785 /*
8786 * If there's data, delay ACK; if there's also a FIN ACKNOW
8787 * will be turned on later.
8788 */
8789 if (DELAY_ACK(tp, bbr, 1) && tlen != 0 && !tfo_partial) {
8790 bbr->bbr_segs_rcvd += 1;
8791 tp->t_flags |= TF_DELACK;
8792 bbr_timer_cancel(bbr, __LINE__, bbr->r_ctl.rc_rcvtime);
8793 } else {
8794 bbr->r_wanted_output = 1;
8795 tp->t_flags |= TF_ACKNOW;
8796 }
8797 if (SEQ_GT(th->th_ack, tp->iss)) {
8798 /*
8799 * The SYN is acked
8800 * handle it specially.
8801 */
8802 bbr_log_syn(tp, to);
8803 }
8804 if (SEQ_GT(th->th_ack, tp->snd_una)) {
8805 /*
8806 * We advance snd_una for the
8807 * fast open case. If th_ack is
8808 * acknowledging data beyond
8809 * snd_una we can't just call
8810 * ack-processing since the
8811 * data stream in our send-map
8812 * will start at snd_una + 1 (one
8813 * beyond the SYN). If its just
8814 * equal we don't need to do that
8815 * and there is no send_map.
8816 */
8817 tp->snd_una++;
8818 }
8819 /*
8820 * Received <SYN,ACK> in SYN_SENT[*] state. Transitions:
8821 * SYN_SENT --> ESTABLISHED SYN_SENT* --> FIN_WAIT_1
8822 */
8823 tp->t_starttime = ticks;
8824 if (tp->t_flags & TF_NEEDFIN) {
8825 tcp_state_change(tp, TCPS_FIN_WAIT_1);
8826 tp->t_flags &= ~TF_NEEDFIN;
8827 thflags &= ~TH_SYN;
8828 } else {
8829 tcp_state_change(tp, TCPS_ESTABLISHED);
8830 TCP_PROBE5(connect__established, NULL, tp,
8831 mtod(m, const char *), tp, th);
8832 cc_conn_init(tp);
8833 }
8834 } else {
8835 /*
8836 * Received initial SYN in SYN-SENT[*] state => simultaneous
8837 * open. If segment contains CC option and there is a
8838 * cached CC, apply TAO test. If it succeeds, connection is *
8839 * half-synchronized. Otherwise, do 3-way handshake:
8840 * SYN-SENT -> SYN-RECEIVED SYN-SENT* -> SYN-RECEIVED* If
8841 * there was no CC option, clear cached CC value.
8842 */
8843 tp->t_flags |= (TF_ACKNOW | TF_NEEDSYN | TF_SONOTCONN);
8844 tcp_state_change(tp, TCPS_SYN_RECEIVED);
8845 }
8846 /*
8847 * Advance th->th_seq to correspond to first data byte. If data,
8848 * trim to stay within window, dropping FIN if necessary.
8849 */
8850 th->th_seq++;
8851 if (tlen > tp->rcv_wnd) {
8852 todrop = tlen - tp->rcv_wnd;
8853 m_adj(m, -todrop);
8854 tlen = tp->rcv_wnd;
8855 thflags &= ~TH_FIN;
8856 KMOD_TCPSTAT_INC(tcps_rcvpackafterwin);
8857 KMOD_TCPSTAT_ADD(tcps_rcvbyteafterwin, todrop);
8858 }
8859 tp->snd_wl1 = th->th_seq - 1;
8860 tp->rcv_up = th->th_seq;
8861 /*
8862 * Client side of transaction: already sent SYN and data. If the
8863 * remote host used T/TCP to validate the SYN, our data will be
8864 * ACK'd; if so, enter normal data segment processing in the middle
8865 * of step 5, ack processing. Otherwise, goto step 6.
8866 */
8867 if (thflags & TH_ACK) {
8868 if ((to->to_flags & TOF_TS) != 0) {
8869 uint32_t t, rtt;
8870
8871 t = tcp_tv_to_mssectick(&bbr->rc_tv);
8872 if (TSTMP_GEQ(t, to->to_tsecr)) {
8873 rtt = t - to->to_tsecr;
8874 if (rtt == 0) {
8875 rtt = 1;
8876 }
8877 rtt *= MS_IN_USEC;
8878 tcp_bbr_xmit_timer(bbr, rtt, 0, 0, 0);
8879 apply_filter_min_small(&bbr->r_ctl.rc_rttprop,
8880 rtt, bbr->r_ctl.rc_rcvtime);
8881 }
8882 }
8883 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val))
8884 return (ret_val);
8885 /* We may have changed to FIN_WAIT_1 above */
8886 if (tp->t_state == TCPS_FIN_WAIT_1) {
8887 /*
8888 * In FIN_WAIT_1 STATE in addition to the processing
8889 * for the ESTABLISHED state if our FIN is now
8890 * acknowledged then enter FIN_WAIT_2.
8891 */
8892 if (ourfinisacked) {
8893 /*
8894 * If we can't receive any more data, then
8895 * closing user can proceed. Starting the
8896 * timer is contrary to the specification,
8897 * but if we don't get a FIN we'll hang
8898 * forever.
8899 *
8900 * XXXjl: we should release the tp also, and
8901 * use a compressed state.
8902 */
8903 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
8904 soisdisconnected(so);
8905 tcp_timer_activate(tp, TT_2MSL,
8906 (tcp_fast_finwait2_recycle ?
8907 tcp_finwait2_timeout :
8908 TP_MAXIDLE(tp)));
8909 }
8910 tcp_state_change(tp, TCPS_FIN_WAIT_2);
8911 }
8912 }
8913 }
8914 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
8915 tiwin, thflags, nxt_pkt));
8916 }
8917
8918 /*
8919 * Return value of 1, the TCB is unlocked and most
8920 * likely gone, return value of 0, the TCB is still
8921 * locked.
8922 */
8923 static int
8924 bbr_do_syn_recv(struct mbuf *m, struct tcphdr *th, struct socket *so,
8925 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
8926 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos)
8927 {
8928 int32_t ourfinisacked = 0;
8929 int32_t ret_val;
8930 struct tcp_bbr *bbr;
8931
8932 INP_WLOCK_ASSERT(tptoinpcb(tp));
8933
8934 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
8935 ctf_calc_rwin(so, tp);
8936 if ((thflags & TH_ACK) &&
8937 (SEQ_LEQ(th->th_ack, tp->snd_una) ||
8938 SEQ_GT(th->th_ack, tp->snd_max))) {
8939 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT);
8940 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
8941 return (1);
8942 }
8943 if (IS_FASTOPEN(tp->t_flags)) {
8944 /*
8945 * When a TFO connection is in SYN_RECEIVED, the only valid
8946 * packets are the initial SYN, a retransmit/copy of the
8947 * initial SYN (possibly with a subset of the original
8948 * data), a valid ACK, a FIN, or a RST.
8949 */
8950 if ((thflags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK)) {
8951 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT);
8952 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
8953 return (1);
8954 } else if (thflags & TH_SYN) {
8955 /* non-initial SYN is ignored */
8956 if ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_RXT) ||
8957 (bbr->r_ctl.rc_hpts_flags & PACE_TMR_TLP) ||
8958 (bbr->r_ctl.rc_hpts_flags & PACE_TMR_RACK)) {
8959 ctf_do_drop(m, NULL);
8960 return (0);
8961 }
8962 } else if (!(thflags & (TH_ACK | TH_FIN | TH_RST))) {
8963 ctf_do_drop(m, NULL);
8964 return (0);
8965 }
8966 }
8967 if ((thflags & TH_RST) ||
8968 (tp->t_fin_is_rst && (thflags & TH_FIN)))
8969 return (ctf_process_rst(m, th, so, tp));
8970 /*
8971 * RFC 1323 PAWS: If we have a timestamp reply on this segment and
8972 * it's less than ts_recent, drop it.
8973 */
8974 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent &&
8975 TSTMP_LT(to->to_tsval, tp->ts_recent)) {
8976 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val))
8977 return (ret_val);
8978 }
8979 /*
8980 * In the SYN-RECEIVED state, validate that the packet belongs to
8981 * this connection before trimming the data to fit the receive
8982 * window. Check the sequence number versus IRS since we know the
8983 * sequence numbers haven't wrapped. This is a partial fix for the
8984 * "LAND" DoS attack.
8985 */
8986 if (SEQ_LT(th->th_seq, tp->irs)) {
8987 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT);
8988 ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
8989 return (1);
8990 }
8991 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) {
8992 return (ret_val);
8993 }
8994 /*
8995 * If last ACK falls within this segment's sequence numbers, record
8996 * its timestamp. NOTE: 1) That the test incorporates suggestions
8997 * from the latest proposal of the tcplw@cray.com list (Braden
8998 * 1993/04/26). 2) That updating only on newer timestamps interferes
8999 * with our earlier PAWS tests, so this check should be solely
9000 * predicated on the sequence space of this segment. 3) That we
9001 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ
9002 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ +
9003 * SEG.Len, This modified check allows us to overcome RFC1323's
9004 * limitations as described in Stevens TCP/IP Illustrated Vol. 2
9005 * p.869. In such cases, we can still calculate the RTT correctly
9006 * when RCV.NXT == Last.ACK.Sent.
9007 */
9008 if ((to->to_flags & TOF_TS) != 0 &&
9009 SEQ_LEQ(th->th_seq, tp->last_ack_sent) &&
9010 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen +
9011 ((thflags & (TH_SYN | TH_FIN)) != 0))) {
9012 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv);
9013 tp->ts_recent = to->to_tsval;
9014 }
9015 tp->snd_wnd = tiwin;
9016 /*
9017 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag
9018 * is on (half-synchronized state), then queue data for later
9019 * processing; else drop segment and return.
9020 */
9021 if ((thflags & TH_ACK) == 0) {
9022 if (IS_FASTOPEN(tp->t_flags)) {
9023 cc_conn_init(tp);
9024 }
9025 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9026 tiwin, thflags, nxt_pkt));
9027 }
9028 KMOD_TCPSTAT_INC(tcps_connects);
9029 if (tp->t_flags & TF_SONOTCONN) {
9030 tp->t_flags &= ~TF_SONOTCONN;
9031 soisconnected(so);
9032 }
9033 /* Do window scaling? */
9034 if ((tp->t_flags & (TF_RCVD_SCALE | TF_REQ_SCALE)) ==
9035 (TF_RCVD_SCALE | TF_REQ_SCALE)) {
9036 tp->rcv_scale = tp->request_r_scale;
9037 }
9038 /*
9039 * ok for the first time in lets see if we can use the ts to figure
9040 * out what the initial RTT was.
9041 */
9042 if ((to->to_flags & TOF_TS) != 0) {
9043 uint32_t t, rtt;
9044
9045 t = tcp_tv_to_mssectick(&bbr->rc_tv);
9046 if (TSTMP_GEQ(t, to->to_tsecr)) {
9047 rtt = t - to->to_tsecr;
9048 if (rtt == 0) {
9049 rtt = 1;
9050 }
9051 rtt *= MS_IN_USEC;
9052 tcp_bbr_xmit_timer(bbr, rtt, 0, 0, 0);
9053 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, bbr->r_ctl.rc_rcvtime);
9054 }
9055 }
9056 /* Drop off any SYN in the send map (probably not there) */
9057 if (thflags & TH_ACK)
9058 bbr_log_syn(tp, to);
9059 if (IS_FASTOPEN(tp->t_flags) && tp->t_tfo_pending) {
9060 tcp_fastopen_decrement_counter(tp->t_tfo_pending);
9061 tp->t_tfo_pending = NULL;
9062 }
9063 /*
9064 * Make transitions: SYN-RECEIVED -> ESTABLISHED SYN-RECEIVED* ->
9065 * FIN-WAIT-1
9066 */
9067 tp->t_starttime = ticks;
9068 if (tp->t_flags & TF_NEEDFIN) {
9069 tcp_state_change(tp, TCPS_FIN_WAIT_1);
9070 tp->t_flags &= ~TF_NEEDFIN;
9071 } else {
9072 tcp_state_change(tp, TCPS_ESTABLISHED);
9073 TCP_PROBE5(accept__established, NULL, tp,
9074 mtod(m, const char *), tp, th);
9075 /*
9076 * TFO connections call cc_conn_init() during SYN
9077 * processing. Calling it again here for such connections
9078 * is not harmless as it would undo the snd_cwnd reduction
9079 * that occurs when a TFO SYN|ACK is retransmitted.
9080 */
9081 if (!IS_FASTOPEN(tp->t_flags))
9082 cc_conn_init(tp);
9083 }
9084 /*
9085 * Account for the ACK of our SYN prior to
9086 * regular ACK processing below, except for
9087 * simultaneous SYN, which is handled later.
9088 */
9089 if (SEQ_GT(th->th_ack, tp->snd_una) && !(tp->t_flags & TF_NEEDSYN))
9090 tp->snd_una++;
9091 /*
9092 * If segment contains data or ACK, will call tcp_reass() later; if
9093 * not, do so now to pass queued data to user.
9094 */
9095 if (tlen == 0 && (thflags & TH_FIN) == 0) {
9096 (void)tcp_reass(tp, (struct tcphdr *)0, NULL, 0,
9097 (struct mbuf *)0);
9098 if (tp->t_flags & TF_WAKESOR) {
9099 tp->t_flags &= ~TF_WAKESOR;
9100 /* NB: sorwakeup_locked() does an implicit unlock. */
9101 sorwakeup_locked(so);
9102 }
9103 }
9104 tp->snd_wl1 = th->th_seq - 1;
9105 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) {
9106 return (ret_val);
9107 }
9108 if (tp->t_state == TCPS_FIN_WAIT_1) {
9109 /* We could have went to FIN_WAIT_1 (or EST) above */
9110 /*
9111 * In FIN_WAIT_1 STATE in addition to the processing for the
9112 * ESTABLISHED state if our FIN is now acknowledged then
9113 * enter FIN_WAIT_2.
9114 */
9115 if (ourfinisacked) {
9116 /*
9117 * If we can't receive any more data, then closing
9118 * user can proceed. Starting the timer is contrary
9119 * to the specification, but if we don't get a FIN
9120 * we'll hang forever.
9121 *
9122 * XXXjl: we should release the tp also, and use a
9123 * compressed state.
9124 */
9125 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
9126 soisdisconnected(so);
9127 tcp_timer_activate(tp, TT_2MSL,
9128 (tcp_fast_finwait2_recycle ?
9129 tcp_finwait2_timeout :
9130 TP_MAXIDLE(tp)));
9131 }
9132 tcp_state_change(tp, TCPS_FIN_WAIT_2);
9133 }
9134 }
9135 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9136 tiwin, thflags, nxt_pkt));
9137 }
9138
9139 /*
9140 * Return value of 1, the TCB is unlocked and most
9141 * likely gone, return value of 0, the TCB is still
9142 * locked.
9143 */
9144 static int
9145 bbr_do_established(struct mbuf *m, struct tcphdr *th, struct socket *so,
9146 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
9147 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos)
9148 {
9149 struct tcp_bbr *bbr;
9150 int32_t ret_val;
9151
9152 INP_WLOCK_ASSERT(tptoinpcb(tp));
9153
9154 /*
9155 * Header prediction: check for the two common cases of a
9156 * uni-directional data xfer. If the packet has no control flags,
9157 * is in-sequence, the window didn't change and we're not
9158 * retransmitting, it's a candidate. If the length is zero and the
9159 * ack moved forward, we're the sender side of the xfer. Just free
9160 * the data acked & wake any higher level process that was blocked
9161 * waiting for space. If the length is non-zero and the ack didn't
9162 * move, we're the receiver side. If we're getting packets in-order
9163 * (the reassembly queue is empty), add the data toc The socket
9164 * buffer and note that we need a delayed ack. Make sure that the
9165 * hidden state-flags are also off. Since we check for
9166 * TCPS_ESTABLISHED first, it can only be TH_NEEDSYN.
9167 */
9168 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
9169 if (bbr->r_ctl.rc_delivered < (4 * tp->t_maxseg)) {
9170 /*
9171 * If we have delived under 4 segments increase the initial
9172 * window if raised by the peer. We use this to determine
9173 * dynamic and static rwnd's at the end of a connection.
9174 */
9175 bbr->r_ctl.rc_init_rwnd = max(tiwin, tp->snd_wnd);
9176 }
9177 if (__predict_true(((to->to_flags & TOF_SACK) == 0)) &&
9178 __predict_true((thflags & (TH_SYN | TH_FIN | TH_RST | TH_URG | TH_ACK)) == TH_ACK) &&
9179 __predict_true(SEGQ_EMPTY(tp)) &&
9180 __predict_true(th->th_seq == tp->rcv_nxt)) {
9181 if (tlen == 0) {
9182 if (bbr_fastack(m, th, so, tp, to, drop_hdrlen, tlen,
9183 tiwin, nxt_pkt, iptos)) {
9184 return (0);
9185 }
9186 } else {
9187 if (bbr_do_fastnewdata(m, th, so, tp, to, drop_hdrlen, tlen,
9188 tiwin, nxt_pkt)) {
9189 return (0);
9190 }
9191 }
9192 }
9193 ctf_calc_rwin(so, tp);
9194
9195 if ((thflags & TH_RST) ||
9196 (tp->t_fin_is_rst && (thflags & TH_FIN)))
9197 return (ctf_process_rst(m, th, so, tp));
9198 /*
9199 * RFC5961 Section 4.2 Send challenge ACK for any SYN in
9200 * synchronized state.
9201 */
9202 if (thflags & TH_SYN) {
9203 ctf_challenge_ack(m, th, tp, iptos, &ret_val);
9204 return (ret_val);
9205 }
9206 /*
9207 * RFC 1323 PAWS: If we have a timestamp reply on this segment and
9208 * it's less than ts_recent, drop it.
9209 */
9210 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent &&
9211 TSTMP_LT(to->to_tsval, tp->ts_recent)) {
9212 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val))
9213 return (ret_val);
9214 }
9215 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) {
9216 return (ret_val);
9217 }
9218 /*
9219 * If last ACK falls within this segment's sequence numbers, record
9220 * its timestamp. NOTE: 1) That the test incorporates suggestions
9221 * from the latest proposal of the tcplw@cray.com list (Braden
9222 * 1993/04/26). 2) That updating only on newer timestamps interferes
9223 * with our earlier PAWS tests, so this check should be solely
9224 * predicated on the sequence space of this segment. 3) That we
9225 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ
9226 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ +
9227 * SEG.Len, This modified check allows us to overcome RFC1323's
9228 * limitations as described in Stevens TCP/IP Illustrated Vol. 2
9229 * p.869. In such cases, we can still calculate the RTT correctly
9230 * when RCV.NXT == Last.ACK.Sent.
9231 */
9232 if ((to->to_flags & TOF_TS) != 0 &&
9233 SEQ_LEQ(th->th_seq, tp->last_ack_sent) &&
9234 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen +
9235 ((thflags & (TH_SYN | TH_FIN)) != 0))) {
9236 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv);
9237 tp->ts_recent = to->to_tsval;
9238 }
9239 /*
9240 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag
9241 * is on (half-synchronized state), then queue data for later
9242 * processing; else drop segment and return.
9243 */
9244 if ((thflags & TH_ACK) == 0) {
9245 if (tp->t_flags & TF_NEEDSYN) {
9246 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9247 tiwin, thflags, nxt_pkt));
9248 } else if (tp->t_flags & TF_ACKNOW) {
9249 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val);
9250 bbr->r_wanted_output = 1;
9251 return (ret_val);
9252 } else {
9253 ctf_do_drop(m, NULL);
9254 return (0);
9255 }
9256 }
9257 /*
9258 * Ack processing.
9259 */
9260 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, NULL, thflags, &ret_val)) {
9261 return (ret_val);
9262 }
9263 if (sbavail(&so->so_snd)) {
9264 if (ctf_progress_timeout_check(tp, true)) {
9265 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__);
9266 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
9267 return (1);
9268 }
9269 }
9270 /* State changes only happen in bbr_process_data() */
9271 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9272 tiwin, thflags, nxt_pkt));
9273 }
9274
9275 /*
9276 * Return value of 1, the TCB is unlocked and most
9277 * likely gone, return value of 0, the TCB is still
9278 * locked.
9279 */
9280 static int
9281 bbr_do_close_wait(struct mbuf *m, struct tcphdr *th, struct socket *so,
9282 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
9283 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos)
9284 {
9285 struct tcp_bbr *bbr;
9286 int32_t ret_val;
9287
9288 INP_WLOCK_ASSERT(tptoinpcb(tp));
9289
9290 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
9291 ctf_calc_rwin(so, tp);
9292 if ((thflags & TH_RST) ||
9293 (tp->t_fin_is_rst && (thflags & TH_FIN)))
9294 return (ctf_process_rst(m, th, so, tp));
9295 /*
9296 * RFC5961 Section 4.2 Send challenge ACK for any SYN in
9297 * synchronized state.
9298 */
9299 if (thflags & TH_SYN) {
9300 ctf_challenge_ack(m, th, tp, iptos, &ret_val);
9301 return (ret_val);
9302 }
9303 /*
9304 * RFC 1323 PAWS: If we have a timestamp reply on this segment and
9305 * it's less than ts_recent, drop it.
9306 */
9307 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent &&
9308 TSTMP_LT(to->to_tsval, tp->ts_recent)) {
9309 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val))
9310 return (ret_val);
9311 }
9312 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) {
9313 return (ret_val);
9314 }
9315 /*
9316 * If last ACK falls within this segment's sequence numbers, record
9317 * its timestamp. NOTE: 1) That the test incorporates suggestions
9318 * from the latest proposal of the tcplw@cray.com list (Braden
9319 * 1993/04/26). 2) That updating only on newer timestamps interferes
9320 * with our earlier PAWS tests, so this check should be solely
9321 * predicated on the sequence space of this segment. 3) That we
9322 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ
9323 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ +
9324 * SEG.Len, This modified check allows us to overcome RFC1323's
9325 * limitations as described in Stevens TCP/IP Illustrated Vol. 2
9326 * p.869. In such cases, we can still calculate the RTT correctly
9327 * when RCV.NXT == Last.ACK.Sent.
9328 */
9329 if ((to->to_flags & TOF_TS) != 0 &&
9330 SEQ_LEQ(th->th_seq, tp->last_ack_sent) &&
9331 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen +
9332 ((thflags & (TH_SYN | TH_FIN)) != 0))) {
9333 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv);
9334 tp->ts_recent = to->to_tsval;
9335 }
9336 /*
9337 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag
9338 * is on (half-synchronized state), then queue data for later
9339 * processing; else drop segment and return.
9340 */
9341 if ((thflags & TH_ACK) == 0) {
9342 if (tp->t_flags & TF_NEEDSYN) {
9343 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9344 tiwin, thflags, nxt_pkt));
9345 } else if (tp->t_flags & TF_ACKNOW) {
9346 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val);
9347 bbr->r_wanted_output = 1;
9348 return (ret_val);
9349 } else {
9350 ctf_do_drop(m, NULL);
9351 return (0);
9352 }
9353 }
9354 /*
9355 * Ack processing.
9356 */
9357 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, NULL, thflags, &ret_val)) {
9358 return (ret_val);
9359 }
9360 if (sbavail(&so->so_snd)) {
9361 if (ctf_progress_timeout_check(tp, true)) {
9362 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__);
9363 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
9364 return (1);
9365 }
9366 }
9367 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9368 tiwin, thflags, nxt_pkt));
9369 }
9370
9371 static int
9372 bbr_check_data_after_close(struct mbuf *m, struct tcp_bbr *bbr,
9373 struct tcpcb *tp, int32_t * tlen, struct tcphdr *th, struct socket *so)
9374 {
9375
9376 if (bbr->rc_allow_data_af_clo == 0) {
9377 close_now:
9378 tcp_log_end_status(tp, TCP_EI_STATUS_DATA_A_CLOSE);
9379 /* tcp_close will kill the inp pre-log the Reset */
9380 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST);
9381 tp = tcp_close(tp);
9382 KMOD_TCPSTAT_INC(tcps_rcvafterclose);
9383 ctf_do_dropwithreset(m, tp, th, BANDLIM_UNLIMITED, (*tlen));
9384 return (1);
9385 }
9386 if (sbavail(&so->so_snd) == 0)
9387 goto close_now;
9388 /* Ok we allow data that is ignored and a followup reset */
9389 tp->rcv_nxt = th->th_seq + *tlen;
9390 tp->t_flags2 |= TF2_DROP_AF_DATA;
9391 bbr->r_wanted_output = 1;
9392 *tlen = 0;
9393 return (0);
9394 }
9395
9396 /*
9397 * Return value of 1, the TCB is unlocked and most
9398 * likely gone, return value of 0, the TCB is still
9399 * locked.
9400 */
9401 static int
9402 bbr_do_fin_wait_1(struct mbuf *m, struct tcphdr *th, struct socket *so,
9403 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
9404 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos)
9405 {
9406 int32_t ourfinisacked = 0;
9407 int32_t ret_val;
9408 struct tcp_bbr *bbr;
9409
9410 INP_WLOCK_ASSERT(tptoinpcb(tp));
9411
9412 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
9413 ctf_calc_rwin(so, tp);
9414 if ((thflags & TH_RST) ||
9415 (tp->t_fin_is_rst && (thflags & TH_FIN)))
9416 return (ctf_process_rst(m, th, so, tp));
9417 /*
9418 * RFC5961 Section 4.2 Send challenge ACK for any SYN in
9419 * synchronized state.
9420 */
9421 if (thflags & TH_SYN) {
9422 ctf_challenge_ack(m, th, tp, iptos, &ret_val);
9423 return (ret_val);
9424 }
9425 /*
9426 * RFC 1323 PAWS: If we have a timestamp reply on this segment and
9427 * it's less than ts_recent, drop it.
9428 */
9429 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent &&
9430 TSTMP_LT(to->to_tsval, tp->ts_recent)) {
9431 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val))
9432 return (ret_val);
9433 }
9434 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) {
9435 return (ret_val);
9436 }
9437 /*
9438 * If new data are received on a connection after the user processes
9439 * are gone, then RST the other end.
9440 * We call a new function now so we might continue and setup
9441 * to reset at all data being ack'd.
9442 */
9443 if ((tp->t_flags & TF_CLOSED) && tlen &&
9444 bbr_check_data_after_close(m, bbr, tp, &tlen, th, so))
9445 return (1);
9446 /*
9447 * If last ACK falls within this segment's sequence numbers, record
9448 * its timestamp. NOTE: 1) That the test incorporates suggestions
9449 * from the latest proposal of the tcplw@cray.com list (Braden
9450 * 1993/04/26). 2) That updating only on newer timestamps interferes
9451 * with our earlier PAWS tests, so this check should be solely
9452 * predicated on the sequence space of this segment. 3) That we
9453 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ
9454 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ +
9455 * SEG.Len, This modified check allows us to overcome RFC1323's
9456 * limitations as described in Stevens TCP/IP Illustrated Vol. 2
9457 * p.869. In such cases, we can still calculate the RTT correctly
9458 * when RCV.NXT == Last.ACK.Sent.
9459 */
9460 if ((to->to_flags & TOF_TS) != 0 &&
9461 SEQ_LEQ(th->th_seq, tp->last_ack_sent) &&
9462 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen +
9463 ((thflags & (TH_SYN | TH_FIN)) != 0))) {
9464 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv);
9465 tp->ts_recent = to->to_tsval;
9466 }
9467 /*
9468 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag
9469 * is on (half-synchronized state), then queue data for later
9470 * processing; else drop segment and return.
9471 */
9472 if ((thflags & TH_ACK) == 0) {
9473 if (tp->t_flags & TF_NEEDSYN) {
9474 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9475 tiwin, thflags, nxt_pkt));
9476 } else if (tp->t_flags & TF_ACKNOW) {
9477 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val);
9478 bbr->r_wanted_output = 1;
9479 return (ret_val);
9480 } else {
9481 ctf_do_drop(m, NULL);
9482 return (0);
9483 }
9484 }
9485 /*
9486 * Ack processing.
9487 */
9488 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) {
9489 return (ret_val);
9490 }
9491 if (ourfinisacked) {
9492 /*
9493 * If we can't receive any more data, then closing user can
9494 * proceed. Starting the timer is contrary to the
9495 * specification, but if we don't get a FIN we'll hang
9496 * forever.
9497 *
9498 * XXXjl: we should release the tp also, and use a
9499 * compressed state.
9500 */
9501 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
9502 soisdisconnected(so);
9503 tcp_timer_activate(tp, TT_2MSL,
9504 (tcp_fast_finwait2_recycle ?
9505 tcp_finwait2_timeout :
9506 TP_MAXIDLE(tp)));
9507 }
9508 tcp_state_change(tp, TCPS_FIN_WAIT_2);
9509 }
9510 if (sbavail(&so->so_snd)) {
9511 if (ctf_progress_timeout_check(tp, true)) {
9512 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__);
9513 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
9514 return (1);
9515 }
9516 }
9517 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9518 tiwin, thflags, nxt_pkt));
9519 }
9520
9521 /*
9522 * Return value of 1, the TCB is unlocked and most
9523 * likely gone, return value of 0, the TCB is still
9524 * locked.
9525 */
9526 static int
9527 bbr_do_closing(struct mbuf *m, struct tcphdr *th, struct socket *so,
9528 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
9529 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos)
9530 {
9531 int32_t ourfinisacked = 0;
9532 int32_t ret_val;
9533 struct tcp_bbr *bbr;
9534
9535 INP_WLOCK_ASSERT(tptoinpcb(tp));
9536
9537 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
9538 ctf_calc_rwin(so, tp);
9539 if ((thflags & TH_RST) ||
9540 (tp->t_fin_is_rst && (thflags & TH_FIN)))
9541 return (ctf_process_rst(m, th, so, tp));
9542 /*
9543 * RFC5961 Section 4.2 Send challenge ACK for any SYN in
9544 * synchronized state.
9545 */
9546 if (thflags & TH_SYN) {
9547 ctf_challenge_ack(m, th, tp, iptos, &ret_val);
9548 return (ret_val);
9549 }
9550 /*
9551 * RFC 1323 PAWS: If we have a timestamp reply on this segment and
9552 * it's less than ts_recent, drop it.
9553 */
9554 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent &&
9555 TSTMP_LT(to->to_tsval, tp->ts_recent)) {
9556 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val))
9557 return (ret_val);
9558 }
9559 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) {
9560 return (ret_val);
9561 }
9562 /*
9563 * If new data are received on a connection after the user processes
9564 * are gone, then RST the other end.
9565 * We call a new function now so we might continue and setup
9566 * to reset at all data being ack'd.
9567 */
9568 if ((tp->t_flags & TF_CLOSED) && tlen &&
9569 bbr_check_data_after_close(m, bbr, tp, &tlen, th, so))
9570 return (1);
9571 /*
9572 * If last ACK falls within this segment's sequence numbers, record
9573 * its timestamp. NOTE: 1) That the test incorporates suggestions
9574 * from the latest proposal of the tcplw@cray.com list (Braden
9575 * 1993/04/26). 2) That updating only on newer timestamps interferes
9576 * with our earlier PAWS tests, so this check should be solely
9577 * predicated on the sequence space of this segment. 3) That we
9578 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ
9579 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ +
9580 * SEG.Len, This modified check allows us to overcome RFC1323's
9581 * limitations as described in Stevens TCP/IP Illustrated Vol. 2
9582 * p.869. In such cases, we can still calculate the RTT correctly
9583 * when RCV.NXT == Last.ACK.Sent.
9584 */
9585 if ((to->to_flags & TOF_TS) != 0 &&
9586 SEQ_LEQ(th->th_seq, tp->last_ack_sent) &&
9587 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen +
9588 ((thflags & (TH_SYN | TH_FIN)) != 0))) {
9589 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv);
9590 tp->ts_recent = to->to_tsval;
9591 }
9592 /*
9593 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag
9594 * is on (half-synchronized state), then queue data for later
9595 * processing; else drop segment and return.
9596 */
9597 if ((thflags & TH_ACK) == 0) {
9598 if (tp->t_flags & TF_NEEDSYN) {
9599 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9600 tiwin, thflags, nxt_pkt));
9601 } else if (tp->t_flags & TF_ACKNOW) {
9602 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val);
9603 bbr->r_wanted_output = 1;
9604 return (ret_val);
9605 } else {
9606 ctf_do_drop(m, NULL);
9607 return (0);
9608 }
9609 }
9610 /*
9611 * Ack processing.
9612 */
9613 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) {
9614 return (ret_val);
9615 }
9616 if (ourfinisacked) {
9617 tcp_twstart(tp);
9618 m_freem(m);
9619 return (1);
9620 }
9621 if (sbavail(&so->so_snd)) {
9622 if (ctf_progress_timeout_check(tp, true)) {
9623 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__);
9624 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
9625 return (1);
9626 }
9627 }
9628 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9629 tiwin, thflags, nxt_pkt));
9630 }
9631
9632 /*
9633 * Return value of 1, the TCB is unlocked and most
9634 * likely gone, return value of 0, the TCB is still
9635 * locked.
9636 */
9637 static int
9638 bbr_do_lastack(struct mbuf *m, struct tcphdr *th, struct socket *so,
9639 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
9640 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos)
9641 {
9642 int32_t ourfinisacked = 0;
9643 int32_t ret_val;
9644 struct tcp_bbr *bbr;
9645
9646 INP_WLOCK_ASSERT(tptoinpcb(tp));
9647
9648 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
9649 ctf_calc_rwin(so, tp);
9650 if ((thflags & TH_RST) ||
9651 (tp->t_fin_is_rst && (thflags & TH_FIN)))
9652 return (ctf_process_rst(m, th, so, tp));
9653 /*
9654 * RFC5961 Section 4.2 Send challenge ACK for any SYN in
9655 * synchronized state.
9656 */
9657 if (thflags & TH_SYN) {
9658 ctf_challenge_ack(m, th, tp, iptos, &ret_val);
9659 return (ret_val);
9660 }
9661 /*
9662 * RFC 1323 PAWS: If we have a timestamp reply on this segment and
9663 * it's less than ts_recent, drop it.
9664 */
9665 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent &&
9666 TSTMP_LT(to->to_tsval, tp->ts_recent)) {
9667 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val))
9668 return (ret_val);
9669 }
9670 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) {
9671 return (ret_val);
9672 }
9673 /*
9674 * If new data are received on a connection after the user processes
9675 * are gone, then RST the other end.
9676 * We call a new function now so we might continue and setup
9677 * to reset at all data being ack'd.
9678 */
9679 if ((tp->t_flags & TF_CLOSED) && tlen &&
9680 bbr_check_data_after_close(m, bbr, tp, &tlen, th, so))
9681 return (1);
9682 /*
9683 * If last ACK falls within this segment's sequence numbers, record
9684 * its timestamp. NOTE: 1) That the test incorporates suggestions
9685 * from the latest proposal of the tcplw@cray.com list (Braden
9686 * 1993/04/26). 2) That updating only on newer timestamps interferes
9687 * with our earlier PAWS tests, so this check should be solely
9688 * predicated on the sequence space of this segment. 3) That we
9689 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ
9690 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ +
9691 * SEG.Len, This modified check allows us to overcome RFC1323's
9692 * limitations as described in Stevens TCP/IP Illustrated Vol. 2
9693 * p.869. In such cases, we can still calculate the RTT correctly
9694 * when RCV.NXT == Last.ACK.Sent.
9695 */
9696 if ((to->to_flags & TOF_TS) != 0 &&
9697 SEQ_LEQ(th->th_seq, tp->last_ack_sent) &&
9698 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen +
9699 ((thflags & (TH_SYN | TH_FIN)) != 0))) {
9700 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv);
9701 tp->ts_recent = to->to_tsval;
9702 }
9703 /*
9704 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag
9705 * is on (half-synchronized state), then queue data for later
9706 * processing; else drop segment and return.
9707 */
9708 if ((thflags & TH_ACK) == 0) {
9709 if (tp->t_flags & TF_NEEDSYN) {
9710 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9711 tiwin, thflags, nxt_pkt));
9712 } else if (tp->t_flags & TF_ACKNOW) {
9713 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val);
9714 bbr->r_wanted_output = 1;
9715 return (ret_val);
9716 } else {
9717 ctf_do_drop(m, NULL);
9718 return (0);
9719 }
9720 }
9721 /*
9722 * case TCPS_LAST_ACK: Ack processing.
9723 */
9724 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) {
9725 return (ret_val);
9726 }
9727 if (ourfinisacked) {
9728 tp = tcp_close(tp);
9729 ctf_do_drop(m, tp);
9730 return (1);
9731 }
9732 if (sbavail(&so->so_snd)) {
9733 if (ctf_progress_timeout_check(tp, true)) {
9734 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__);
9735 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
9736 return (1);
9737 }
9738 }
9739 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9740 tiwin, thflags, nxt_pkt));
9741 }
9742
9743 /*
9744 * Return value of 1, the TCB is unlocked and most
9745 * likely gone, return value of 0, the TCB is still
9746 * locked.
9747 */
9748 static int
9749 bbr_do_fin_wait_2(struct mbuf *m, struct tcphdr *th, struct socket *so,
9750 struct tcpcb *tp, struct tcpopt *to, int32_t drop_hdrlen, int32_t tlen,
9751 uint32_t tiwin, int32_t thflags, int32_t nxt_pkt, uint8_t iptos)
9752 {
9753 int32_t ourfinisacked = 0;
9754 int32_t ret_val;
9755 struct tcp_bbr *bbr;
9756
9757 INP_WLOCK_ASSERT(tptoinpcb(tp));
9758
9759 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
9760 ctf_calc_rwin(so, tp);
9761 /* Reset receive buffer auto scaling when not in bulk receive mode. */
9762 if ((thflags & TH_RST) ||
9763 (tp->t_fin_is_rst && (thflags & TH_FIN)))
9764 return (ctf_process_rst(m, th, so, tp));
9765
9766 /*
9767 * RFC5961 Section 4.2 Send challenge ACK for any SYN in
9768 * synchronized state.
9769 */
9770 if (thflags & TH_SYN) {
9771 ctf_challenge_ack(m, th, tp, iptos, &ret_val);
9772 return (ret_val);
9773 }
9774 /*
9775 * RFC 1323 PAWS: If we have a timestamp reply on this segment and
9776 * it's less than ts_recent, drop it.
9777 */
9778 if ((to->to_flags & TOF_TS) != 0 && tp->ts_recent &&
9779 TSTMP_LT(to->to_tsval, tp->ts_recent)) {
9780 if (ctf_ts_check(m, th, tp, tlen, thflags, &ret_val))
9781 return (ret_val);
9782 }
9783 if (ctf_drop_checks(to, m, th, tp, &tlen, &thflags, &drop_hdrlen, &ret_val)) {
9784 return (ret_val);
9785 }
9786 /*
9787 * If new data are received on a connection after the user processes
9788 * are gone, then we may RST the other end depending on the outcome
9789 * of bbr_check_data_after_close.
9790 * We call a new function now so we might continue and setup
9791 * to reset at all data being ack'd.
9792 */
9793 if ((tp->t_flags & TF_CLOSED) && tlen &&
9794 bbr_check_data_after_close(m, bbr, tp, &tlen, th, so))
9795 return (1);
9796 /*
9797 * If last ACK falls within this segment's sequence numbers, record
9798 * its timestamp. NOTE: 1) That the test incorporates suggestions
9799 * from the latest proposal of the tcplw@cray.com list (Braden
9800 * 1993/04/26). 2) That updating only on newer timestamps interferes
9801 * with our earlier PAWS tests, so this check should be solely
9802 * predicated on the sequence space of this segment. 3) That we
9803 * modify the segment boundary check to be Last.ACK.Sent <= SEG.SEQ
9804 * + SEG.Len instead of RFC1323's Last.ACK.Sent < SEG.SEQ +
9805 * SEG.Len, This modified check allows us to overcome RFC1323's
9806 * limitations as described in Stevens TCP/IP Illustrated Vol. 2
9807 * p.869. In such cases, we can still calculate the RTT correctly
9808 * when RCV.NXT == Last.ACK.Sent.
9809 */
9810 if ((to->to_flags & TOF_TS) != 0 &&
9811 SEQ_LEQ(th->th_seq, tp->last_ack_sent) &&
9812 SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen +
9813 ((thflags & (TH_SYN | TH_FIN)) != 0))) {
9814 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv);
9815 tp->ts_recent = to->to_tsval;
9816 }
9817 /*
9818 * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN flag
9819 * is on (half-synchronized state), then queue data for later
9820 * processing; else drop segment and return.
9821 */
9822 if ((thflags & TH_ACK) == 0) {
9823 if (tp->t_flags & TF_NEEDSYN) {
9824 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9825 tiwin, thflags, nxt_pkt));
9826 } else if (tp->t_flags & TF_ACKNOW) {
9827 ctf_do_dropafterack(m, tp, th, thflags, tlen, &ret_val);
9828 bbr->r_wanted_output = 1;
9829 return (ret_val);
9830 } else {
9831 ctf_do_drop(m, NULL);
9832 return (0);
9833 }
9834 }
9835 /*
9836 * Ack processing.
9837 */
9838 if (bbr_process_ack(m, th, so, tp, to, tiwin, tlen, &ourfinisacked, thflags, &ret_val)) {
9839 return (ret_val);
9840 }
9841 if (sbavail(&so->so_snd)) {
9842 if (ctf_progress_timeout_check(tp, true)) {
9843 bbr_log_progress_event(bbr, tp, tick, PROGRESS_DROP, __LINE__);
9844 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
9845 return (1);
9846 }
9847 }
9848 return (bbr_process_data(m, th, so, tp, drop_hdrlen, tlen,
9849 tiwin, thflags, nxt_pkt));
9850 }
9851
9852 static void
9853 bbr_stop_all_timers(struct tcpcb *tp)
9854 {
9855 struct tcp_bbr *bbr;
9856
9857 /*
9858 * Assure no timers are running.
9859 */
9860 if (tcp_timer_active(tp, TT_PERSIST)) {
9861 /* We enter in persists, set the flag appropriately */
9862 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
9863 bbr->rc_in_persist = 1;
9864 }
9865 }
9866
9867 static void
9868 bbr_google_mode_on(struct tcp_bbr *bbr)
9869 {
9870 bbr->rc_use_google = 1;
9871 bbr->rc_no_pacing = 0;
9872 bbr->r_ctl.bbr_google_discount = bbr_google_discount;
9873 bbr->r_use_policer = bbr_policer_detection_enabled;
9874 bbr->r_ctl.rc_probertt_int = (USECS_IN_SECOND * 10);
9875 bbr->bbr_use_rack_cheat = 0;
9876 bbr->r_ctl.rc_incr_tmrs = 0;
9877 bbr->r_ctl.rc_inc_tcp_oh = 0;
9878 bbr->r_ctl.rc_inc_ip_oh = 0;
9879 bbr->r_ctl.rc_inc_enet_oh = 0;
9880 reset_time(&bbr->r_ctl.rc_delrate,
9881 BBR_NUM_RTTS_FOR_GOOG_DEL_LIMIT);
9882 reset_time_small(&bbr->r_ctl.rc_rttprop,
9883 (11 * USECS_IN_SECOND));
9884 tcp_bbr_tso_size_check(bbr, tcp_get_usecs(&bbr->rc_tv));
9885 }
9886
9887 static void
9888 bbr_google_mode_off(struct tcp_bbr *bbr)
9889 {
9890 bbr->rc_use_google = 0;
9891 bbr->r_ctl.bbr_google_discount = 0;
9892 bbr->no_pacing_until = bbr_no_pacing_until;
9893 bbr->r_use_policer = 0;
9894 if (bbr->no_pacing_until)
9895 bbr->rc_no_pacing = 1;
9896 else
9897 bbr->rc_no_pacing = 0;
9898 if (bbr_use_rack_resend_cheat)
9899 bbr->bbr_use_rack_cheat = 1;
9900 else
9901 bbr->bbr_use_rack_cheat = 0;
9902 if (bbr_incr_timers)
9903 bbr->r_ctl.rc_incr_tmrs = 1;
9904 else
9905 bbr->r_ctl.rc_incr_tmrs = 0;
9906 if (bbr_include_tcp_oh)
9907 bbr->r_ctl.rc_inc_tcp_oh = 1;
9908 else
9909 bbr->r_ctl.rc_inc_tcp_oh = 0;
9910 if (bbr_include_ip_oh)
9911 bbr->r_ctl.rc_inc_ip_oh = 1;
9912 else
9913 bbr->r_ctl.rc_inc_ip_oh = 0;
9914 if (bbr_include_enet_oh)
9915 bbr->r_ctl.rc_inc_enet_oh = 1;
9916 else
9917 bbr->r_ctl.rc_inc_enet_oh = 0;
9918 bbr->r_ctl.rc_probertt_int = bbr_rtt_probe_limit;
9919 reset_time(&bbr->r_ctl.rc_delrate,
9920 bbr_num_pktepo_for_del_limit);
9921 reset_time_small(&bbr->r_ctl.rc_rttprop,
9922 (bbr_filter_len_sec * USECS_IN_SECOND));
9923 tcp_bbr_tso_size_check(bbr, tcp_get_usecs(&bbr->rc_tv));
9924 }
9925 /*
9926 * Return 0 on success, non-zero on failure
9927 * which indicates the error (usually no memory).
9928 */
9929 static int
9930 bbr_init(struct tcpcb *tp)
9931 {
9932 struct inpcb *inp = tptoinpcb(tp);
9933 struct tcp_bbr *bbr = NULL;
9934 uint32_t cts;
9935
9936 tp->t_fb_ptr = uma_zalloc(bbr_pcb_zone, (M_NOWAIT | M_ZERO));
9937 if (tp->t_fb_ptr == NULL) {
9938 /*
9939 * We need to allocate memory but cant. The INP and INP_INFO
9940 * locks and they are recursive (happens during setup. So a
9941 * scheme to drop the locks fails :(
9942 *
9943 */
9944 return (ENOMEM);
9945 }
9946 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
9947 bbr->rtt_valid = 0;
9948 inp->inp_flags2 |= INP_CANNOT_DO_ECN;
9949 inp->inp_flags2 |= INP_SUPPORTS_MBUFQ;
9950 TAILQ_INIT(&bbr->r_ctl.rc_map);
9951 TAILQ_INIT(&bbr->r_ctl.rc_free);
9952 TAILQ_INIT(&bbr->r_ctl.rc_tmap);
9953 bbr->rc_tp = tp;
9954 bbr->rc_inp = inp;
9955 cts = tcp_get_usecs(&bbr->rc_tv);
9956 tp->t_acktime = 0;
9957 bbr->rc_allow_data_af_clo = bbr_ignore_data_after_close;
9958 bbr->r_ctl.rc_reorder_fade = bbr_reorder_fade;
9959 bbr->rc_tlp_threshold = bbr_tlp_thresh;
9960 bbr->r_ctl.rc_reorder_shift = bbr_reorder_thresh;
9961 bbr->r_ctl.rc_pkt_delay = bbr_pkt_delay;
9962 bbr->r_ctl.rc_min_to = bbr_min_to;
9963 bbr->rc_bbr_state = BBR_STATE_STARTUP;
9964 bbr->r_ctl.bbr_lost_at_state = 0;
9965 bbr->r_ctl.rc_lost_at_startup = 0;
9966 bbr->rc_all_timers_stopped = 0;
9967 bbr->r_ctl.rc_bbr_lastbtlbw = 0;
9968 bbr->r_ctl.rc_pkt_epoch_del = 0;
9969 bbr->r_ctl.rc_pkt_epoch = 0;
9970 bbr->r_ctl.rc_lowest_rtt = 0xffffffff;
9971 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_high_gain;
9972 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_high_gain;
9973 bbr->r_ctl.rc_went_idle_time = cts;
9974 bbr->rc_pacer_started = cts;
9975 bbr->r_ctl.rc_pkt_epoch_time = cts;
9976 bbr->r_ctl.rc_rcvtime = cts;
9977 bbr->r_ctl.rc_bbr_state_time = cts;
9978 bbr->r_ctl.rc_del_time = cts;
9979 bbr->r_ctl.rc_tlp_rxt_last_time = cts;
9980 bbr->r_ctl.last_in_probertt = cts;
9981 bbr->skip_gain = 0;
9982 bbr->gain_is_limited = 0;
9983 bbr->no_pacing_until = bbr_no_pacing_until;
9984 if (bbr->no_pacing_until)
9985 bbr->rc_no_pacing = 1;
9986 if (bbr_use_google_algo) {
9987 bbr->rc_no_pacing = 0;
9988 bbr->rc_use_google = 1;
9989 bbr->r_ctl.bbr_google_discount = bbr_google_discount;
9990 bbr->r_use_policer = bbr_policer_detection_enabled;
9991 } else {
9992 bbr->rc_use_google = 0;
9993 bbr->r_ctl.bbr_google_discount = 0;
9994 bbr->r_use_policer = 0;
9995 }
9996 if (bbr_ts_limiting)
9997 bbr->rc_use_ts_limit = 1;
9998 else
9999 bbr->rc_use_ts_limit = 0;
10000 if (bbr_ts_can_raise)
10001 bbr->ts_can_raise = 1;
10002 else
10003 bbr->ts_can_raise = 0;
10004 if (V_tcp_delack_enabled == 1)
10005 tp->t_delayed_ack = 2;
10006 else if (V_tcp_delack_enabled == 0)
10007 tp->t_delayed_ack = 0;
10008 else if (V_tcp_delack_enabled < 100)
10009 tp->t_delayed_ack = V_tcp_delack_enabled;
10010 else
10011 tp->t_delayed_ack = 2;
10012 if (bbr->rc_use_google == 0)
10013 bbr->r_ctl.rc_probertt_int = bbr_rtt_probe_limit;
10014 else
10015 bbr->r_ctl.rc_probertt_int = (USECS_IN_SECOND * 10);
10016 bbr->r_ctl.rc_min_rto_ms = bbr_rto_min_ms;
10017 bbr->rc_max_rto_sec = bbr_rto_max_sec;
10018 bbr->rc_init_win = bbr_def_init_win;
10019 if (tp->t_flags & TF_REQ_TSTMP)
10020 bbr->rc_last_options = TCP_TS_OVERHEAD;
10021 bbr->r_ctl.rc_pace_max_segs = tp->t_maxseg - bbr->rc_last_options;
10022 bbr->r_ctl.rc_high_rwnd = tp->snd_wnd;
10023 bbr->r_init_rtt = 1;
10024
10025 counter_u64_add(bbr_flows_nohdwr_pacing, 1);
10026 if (bbr_allow_hdwr_pacing)
10027 bbr->bbr_hdw_pace_ena = 1;
10028 else
10029 bbr->bbr_hdw_pace_ena = 0;
10030 if (bbr_sends_full_iwnd)
10031 bbr->bbr_init_win_cheat = 1;
10032 else
10033 bbr->bbr_init_win_cheat = 0;
10034 bbr->r_ctl.bbr_utter_max = bbr_hptsi_utter_max;
10035 bbr->r_ctl.rc_drain_pg = bbr_drain_gain;
10036 bbr->r_ctl.rc_startup_pg = bbr_high_gain;
10037 bbr->rc_loss_exit = bbr_exit_startup_at_loss;
10038 bbr->r_ctl.bbr_rttprobe_gain_val = bbr_rttprobe_gain;
10039 bbr->r_ctl.bbr_hptsi_per_second = bbr_hptsi_per_second;
10040 bbr->r_ctl.bbr_hptsi_segments_delay_tar = bbr_hptsi_segments_delay_tar;
10041 bbr->r_ctl.bbr_hptsi_segments_max = bbr_hptsi_segments_max;
10042 bbr->r_ctl.bbr_hptsi_segments_floor = bbr_hptsi_segments_floor;
10043 bbr->r_ctl.bbr_hptsi_bytes_min = bbr_hptsi_bytes_min;
10044 bbr->r_ctl.bbr_cross_over = bbr_cross_over;
10045 bbr->r_ctl.rc_rtt_shrinks = cts;
10046 if (bbr->rc_use_google) {
10047 setup_time_filter(&bbr->r_ctl.rc_delrate,
10048 FILTER_TYPE_MAX,
10049 BBR_NUM_RTTS_FOR_GOOG_DEL_LIMIT);
10050 setup_time_filter_small(&bbr->r_ctl.rc_rttprop,
10051 FILTER_TYPE_MIN, (11 * USECS_IN_SECOND));
10052 } else {
10053 setup_time_filter(&bbr->r_ctl.rc_delrate,
10054 FILTER_TYPE_MAX,
10055 bbr_num_pktepo_for_del_limit);
10056 setup_time_filter_small(&bbr->r_ctl.rc_rttprop,
10057 FILTER_TYPE_MIN, (bbr_filter_len_sec * USECS_IN_SECOND));
10058 }
10059 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_INIT, 0);
10060 if (bbr_uses_idle_restart)
10061 bbr->rc_use_idle_restart = 1;
10062 else
10063 bbr->rc_use_idle_restart = 0;
10064 bbr->r_ctl.rc_bbr_cur_del_rate = 0;
10065 bbr->r_ctl.rc_initial_hptsi_bw = bbr_initial_bw_bps;
10066 if (bbr_resends_use_tso)
10067 bbr->rc_resends_use_tso = 1;
10068 #ifdef NETFLIX_PEAKRATE
10069 tp->t_peakrate_thr = tp->t_maxpeakrate;
10070 #endif
10071 if (tp->snd_una != tp->snd_max) {
10072 /* Create a send map for the current outstanding data */
10073 struct bbr_sendmap *rsm;
10074
10075 rsm = bbr_alloc(bbr);
10076 if (rsm == NULL) {
10077 uma_zfree(bbr_pcb_zone, tp->t_fb_ptr);
10078 tp->t_fb_ptr = NULL;
10079 return (ENOMEM);
10080 }
10081 rsm->r_rtt_not_allowed = 1;
10082 rsm->r_tim_lastsent[0] = cts;
10083 rsm->r_rtr_cnt = 1;
10084 rsm->r_rtr_bytes = 0;
10085 rsm->r_start = tp->snd_una;
10086 rsm->r_end = tp->snd_max;
10087 rsm->r_dupack = 0;
10088 rsm->r_delivered = bbr->r_ctl.rc_delivered;
10089 rsm->r_ts_valid = 0;
10090 rsm->r_del_ack_ts = tp->ts_recent;
10091 rsm->r_del_time = cts;
10092 if (bbr->r_ctl.r_app_limited_until)
10093 rsm->r_app_limited = 1;
10094 else
10095 rsm->r_app_limited = 0;
10096 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_map, rsm, r_next);
10097 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_tmap, rsm, r_tnext);
10098 rsm->r_in_tmap = 1;
10099 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW)
10100 rsm->r_bbr_state = bbr_state_val(bbr);
10101 else
10102 rsm->r_bbr_state = 8;
10103 }
10104 if (bbr_use_rack_resend_cheat && (bbr->rc_use_google == 0))
10105 bbr->bbr_use_rack_cheat = 1;
10106 if (bbr_incr_timers && (bbr->rc_use_google == 0))
10107 bbr->r_ctl.rc_incr_tmrs = 1;
10108 if (bbr_include_tcp_oh && (bbr->rc_use_google == 0))
10109 bbr->r_ctl.rc_inc_tcp_oh = 1;
10110 if (bbr_include_ip_oh && (bbr->rc_use_google == 0))
10111 bbr->r_ctl.rc_inc_ip_oh = 1;
10112 if (bbr_include_enet_oh && (bbr->rc_use_google == 0))
10113 bbr->r_ctl.rc_inc_enet_oh = 1;
10114
10115 bbr_log_type_statechange(bbr, cts, __LINE__);
10116 if (TCPS_HAVEESTABLISHED(tp->t_state) &&
10117 (tp->t_srtt)) {
10118 uint32_t rtt;
10119
10120 rtt = (TICKS_2_USEC(tp->t_srtt) >> TCP_RTT_SHIFT);
10121 apply_filter_min_small(&bbr->r_ctl.rc_rttprop, rtt, cts);
10122 }
10123 /* announce the settings and state */
10124 bbr_log_settings_change(bbr, BBR_RECOVERY_LOWRTT);
10125 tcp_bbr_tso_size_check(bbr, cts);
10126 /*
10127 * Now call the generic function to start a timer. This will place
10128 * the TCB on the hptsi wheel if a timer is needed with appropriate
10129 * flags.
10130 */
10131 bbr_stop_all_timers(tp);
10132 bbr_start_hpts_timer(bbr, tp, cts, 5, 0, 0);
10133 return (0);
10134 }
10135
10136 /*
10137 * Return 0 if we can accept the connection. Return
10138 * non-zero if we can't handle the connection. A EAGAIN
10139 * means you need to wait until the connection is up.
10140 * a EADDRNOTAVAIL means we can never handle the connection
10141 * (no SACK).
10142 */
10143 static int
10144 bbr_handoff_ok(struct tcpcb *tp)
10145 {
10146 if ((tp->t_state == TCPS_CLOSED) ||
10147 (tp->t_state == TCPS_LISTEN)) {
10148 /* Sure no problem though it may not stick */
10149 return (0);
10150 }
10151 if ((tp->t_state == TCPS_SYN_SENT) ||
10152 (tp->t_state == TCPS_SYN_RECEIVED)) {
10153 /*
10154 * We really don't know you have to get to ESTAB or beyond
10155 * to tell.
10156 */
10157 return (EAGAIN);
10158 }
10159 if (tp->t_flags & TF_SENTFIN)
10160 return (EINVAL);
10161 if ((tp->t_flags & TF_SACK_PERMIT) || bbr_sack_not_required) {
10162 return (0);
10163 }
10164 /*
10165 * If we reach here we don't do SACK on this connection so we can
10166 * never do rack.
10167 */
10168 return (EINVAL);
10169 }
10170
10171 static void
10172 bbr_fini(struct tcpcb *tp, int32_t tcb_is_purged)
10173 {
10174 if (tp->t_fb_ptr) {
10175 struct inpcb *inp = tptoinpcb(tp);
10176 uint32_t calc;
10177 struct tcp_bbr *bbr;
10178 struct bbr_sendmap *rsm;
10179
10180 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
10181 if (bbr->r_ctl.crte)
10182 tcp_rel_pacing_rate(bbr->r_ctl.crte, bbr->rc_tp);
10183 bbr_log_flowend(bbr);
10184 bbr->rc_tp = NULL;
10185 /* Backout any flags2 we applied */
10186 inp->inp_flags2 &= ~INP_CANNOT_DO_ECN;
10187 inp->inp_flags2 &= ~INP_SUPPORTS_MBUFQ;
10188 inp->inp_flags2 &= ~INP_MBUF_QUEUE_READY;
10189 if (bbr->bbr_hdrw_pacing)
10190 counter_u64_add(bbr_flows_whdwr_pacing, -1);
10191 else
10192 counter_u64_add(bbr_flows_nohdwr_pacing, -1);
10193 if (bbr->r_ctl.crte != NULL) {
10194 tcp_rel_pacing_rate(bbr->r_ctl.crte, tp);
10195 bbr->r_ctl.crte = NULL;
10196 }
10197 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map);
10198 while (rsm) {
10199 TAILQ_REMOVE(&bbr->r_ctl.rc_map, rsm, r_next);
10200 uma_zfree(bbr_zone, rsm);
10201 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map);
10202 }
10203 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_free);
10204 while (rsm) {
10205 TAILQ_REMOVE(&bbr->r_ctl.rc_free, rsm, r_next);
10206 uma_zfree(bbr_zone, rsm);
10207 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_free);
10208 }
10209 calc = bbr->r_ctl.rc_high_rwnd - bbr->r_ctl.rc_init_rwnd;
10210 if (calc > (bbr->r_ctl.rc_init_rwnd / 10))
10211 BBR_STAT_INC(bbr_dynamic_rwnd);
10212 else
10213 BBR_STAT_INC(bbr_static_rwnd);
10214 bbr->r_ctl.rc_free_cnt = 0;
10215 uma_zfree(bbr_pcb_zone, tp->t_fb_ptr);
10216 tp->t_fb_ptr = NULL;
10217 }
10218 /* Make sure snd_nxt is correctly set */
10219 tp->snd_nxt = tp->snd_max;
10220 }
10221
10222 static void
10223 bbr_set_state(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t win)
10224 {
10225 switch (tp->t_state) {
10226 case TCPS_SYN_SENT:
10227 bbr->r_state = TCPS_SYN_SENT;
10228 bbr->r_substate = bbr_do_syn_sent;
10229 break;
10230 case TCPS_SYN_RECEIVED:
10231 bbr->r_state = TCPS_SYN_RECEIVED;
10232 bbr->r_substate = bbr_do_syn_recv;
10233 break;
10234 case TCPS_ESTABLISHED:
10235 bbr->r_ctl.rc_init_rwnd = max(win, bbr->rc_tp->snd_wnd);
10236 bbr->r_state = TCPS_ESTABLISHED;
10237 bbr->r_substate = bbr_do_established;
10238 break;
10239 case TCPS_CLOSE_WAIT:
10240 bbr->r_state = TCPS_CLOSE_WAIT;
10241 bbr->r_substate = bbr_do_close_wait;
10242 break;
10243 case TCPS_FIN_WAIT_1:
10244 bbr->r_state = TCPS_FIN_WAIT_1;
10245 bbr->r_substate = bbr_do_fin_wait_1;
10246 break;
10247 case TCPS_CLOSING:
10248 bbr->r_state = TCPS_CLOSING;
10249 bbr->r_substate = bbr_do_closing;
10250 break;
10251 case TCPS_LAST_ACK:
10252 bbr->r_state = TCPS_LAST_ACK;
10253 bbr->r_substate = bbr_do_lastack;
10254 break;
10255 case TCPS_FIN_WAIT_2:
10256 bbr->r_state = TCPS_FIN_WAIT_2;
10257 bbr->r_substate = bbr_do_fin_wait_2;
10258 break;
10259 case TCPS_LISTEN:
10260 case TCPS_CLOSED:
10261 case TCPS_TIME_WAIT:
10262 default:
10263 break;
10264 };
10265 }
10266
10267 static void
10268 bbr_substate_change(struct tcp_bbr *bbr, uint32_t cts, int32_t line, int dolog)
10269 {
10270 /*
10271 * Now what state are we going into now? Is there adjustments
10272 * needed?
10273 */
10274 int32_t old_state;
10275
10276 old_state = bbr_state_val(bbr);
10277 if (bbr_state_val(bbr) == BBR_SUB_LEVEL1) {
10278 /* Save the lowest srtt we saw in our end of the sub-state */
10279 bbr->rc_hit_state_1 = 0;
10280 if (bbr->r_ctl.bbr_smallest_srtt_this_state != 0xffffffff)
10281 bbr->r_ctl.bbr_smallest_srtt_state2 = bbr->r_ctl.bbr_smallest_srtt_this_state;
10282 }
10283 bbr->rc_bbr_substate++;
10284 if (bbr->rc_bbr_substate >= BBR_SUBSTATE_COUNT) {
10285 /* Cycle back to first state-> gain */
10286 bbr->rc_bbr_substate = 0;
10287 }
10288 if (bbr_state_val(bbr) == BBR_SUB_GAIN) {
10289 /*
10290 * We enter the gain(5/4) cycle (possibly less if
10291 * shallow buffer detection is enabled)
10292 */
10293 if (bbr->skip_gain) {
10294 /*
10295 * Hardware pacing has set our rate to
10296 * the max and limited our b/w just
10297 * do level i.e. no gain.
10298 */
10299 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_LEVEL1];
10300 } else if (bbr->gain_is_limited &&
10301 bbr->bbr_hdrw_pacing &&
10302 bbr->r_ctl.crte) {
10303 /*
10304 * We can't gain above the hardware pacing
10305 * rate which is less than our rate + the gain
10306 * calculate the gain needed to reach the hardware
10307 * pacing rate..
10308 */
10309 uint64_t bw, rate, gain_calc;
10310
10311 bw = bbr_get_bw(bbr);
10312 rate = bbr->r_ctl.crte->rate;
10313 if ((rate > bw) &&
10314 (((bw * (uint64_t)bbr_hptsi_gain[BBR_SUB_GAIN]) / (uint64_t)BBR_UNIT) > rate)) {
10315 gain_calc = (rate * BBR_UNIT) / bw;
10316 if (gain_calc < BBR_UNIT)
10317 gain_calc = BBR_UNIT;
10318 bbr->r_ctl.rc_bbr_hptsi_gain = (uint16_t)gain_calc;
10319 } else {
10320 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_GAIN];
10321 }
10322 } else
10323 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_GAIN];
10324 if ((bbr->rc_use_google == 0) && (bbr_gain_to_target == 0)) {
10325 bbr->r_ctl.rc_bbr_state_atflight = cts;
10326 } else
10327 bbr->r_ctl.rc_bbr_state_atflight = 0;
10328 } else if (bbr_state_val(bbr) == BBR_SUB_DRAIN) {
10329 bbr->rc_hit_state_1 = 1;
10330 bbr->r_ctl.rc_exta_time_gd = 0;
10331 bbr->r_ctl.flightsize_at_drain = ctf_flight_size(bbr->rc_tp,
10332 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
10333 if (bbr_state_drain_2_tar) {
10334 bbr->r_ctl.rc_bbr_state_atflight = 0;
10335 } else
10336 bbr->r_ctl.rc_bbr_state_atflight = cts;
10337 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[BBR_SUB_DRAIN];
10338 } else {
10339 /* All other cycles hit here 2-7 */
10340 if ((old_state == BBR_SUB_DRAIN) && bbr->rc_hit_state_1) {
10341 if (bbr_sub_drain_slam_cwnd &&
10342 (bbr->rc_use_google == 0) &&
10343 (bbr->rc_tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd)) {
10344 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd;
10345 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
10346 }
10347 if ((cts - bbr->r_ctl.rc_bbr_state_time) > bbr_get_rtt(bbr, BBR_RTT_PROP))
10348 bbr->r_ctl.rc_exta_time_gd += ((cts - bbr->r_ctl.rc_bbr_state_time) -
10349 bbr_get_rtt(bbr, BBR_RTT_PROP));
10350 else
10351 bbr->r_ctl.rc_exta_time_gd = 0;
10352 if (bbr->r_ctl.rc_exta_time_gd) {
10353 bbr->r_ctl.rc_level_state_extra = bbr->r_ctl.rc_exta_time_gd;
10354 /* Now chop up the time for each state (div by 7) */
10355 bbr->r_ctl.rc_level_state_extra /= 7;
10356 if (bbr_rand_ot && bbr->r_ctl.rc_level_state_extra) {
10357 /* Add a randomization */
10358 bbr_randomize_extra_state_time(bbr);
10359 }
10360 }
10361 }
10362 bbr->r_ctl.rc_bbr_state_atflight = max(1, cts);
10363 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_hptsi_gain[bbr_state_val(bbr)];
10364 }
10365 if (bbr->rc_use_google) {
10366 bbr->r_ctl.rc_bbr_state_atflight = max(1, cts);
10367 }
10368 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost;
10369 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_cwnd_gain;
10370 if (dolog)
10371 bbr_log_type_statechange(bbr, cts, line);
10372
10373 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) {
10374 uint32_t time_in;
10375
10376 time_in = cts - bbr->r_ctl.rc_bbr_state_time;
10377 if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) {
10378 counter_u64_add(bbr_state_time[(old_state + 5)], time_in);
10379 } else {
10380 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in);
10381 }
10382 }
10383 bbr->r_ctl.bbr_smallest_srtt_this_state = 0xffffffff;
10384 bbr_set_state_target(bbr, __LINE__);
10385 if (bbr_sub_drain_slam_cwnd &&
10386 (bbr->rc_use_google == 0) &&
10387 (bbr_state_val(bbr) == BBR_SUB_DRAIN)) {
10388 /* Slam down the cwnd */
10389 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd;
10390 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state;
10391 if (bbr_sub_drain_app_limit) {
10392 /* Go app limited if we are on a long drain */
10393 bbr->r_ctl.r_app_limited_until = (bbr->r_ctl.rc_delivered +
10394 ctf_flight_size(bbr->rc_tp,
10395 (bbr->r_ctl.rc_sacked +
10396 bbr->r_ctl.rc_lost_bytes)));
10397 }
10398 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
10399 }
10400 if (bbr->rc_lt_use_bw) {
10401 /* In policed mode we clamp pacing_gain to BBR_UNIT */
10402 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT;
10403 }
10404 /* Google changes TSO size every cycle */
10405 if (bbr->rc_use_google)
10406 tcp_bbr_tso_size_check(bbr, cts);
10407 bbr->r_ctl.gain_epoch = cts;
10408 bbr->r_ctl.rc_bbr_state_time = cts;
10409 bbr->r_ctl.substate_pe = bbr->r_ctl.rc_pkt_epoch;
10410 }
10411
10412 static void
10413 bbr_set_probebw_google_gains(struct tcp_bbr *bbr, uint32_t cts, uint32_t losses)
10414 {
10415 if ((bbr_state_val(bbr) == BBR_SUB_DRAIN) &&
10416 (google_allow_early_out == 1) &&
10417 (bbr->r_ctl.rc_flight_at_input <= bbr->r_ctl.rc_target_at_state)) {
10418 /* We have reached out target flight size possibly early */
10419 goto change_state;
10420 }
10421 if (TSTMP_LT(cts, bbr->r_ctl.rc_bbr_state_time)) {
10422 return;
10423 }
10424 if ((cts - bbr->r_ctl.rc_bbr_state_time) < bbr_get_rtt(bbr, BBR_RTT_PROP)) {
10425 /*
10426 * Must be a rttProp movement forward before
10427 * we can change states.
10428 */
10429 return;
10430 }
10431 if (bbr_state_val(bbr) == BBR_SUB_GAIN) {
10432 /*
10433 * The needed time has passed but for
10434 * the gain cycle extra rules apply:
10435 * 1) If we have seen loss, we exit
10436 * 2) If we have not reached the target
10437 * we stay in GAIN (gain-to-target).
10438 */
10439 if (google_consider_lost && losses)
10440 goto change_state;
10441 if (bbr->r_ctl.rc_target_at_state > bbr->r_ctl.rc_flight_at_input) {
10442 return;
10443 }
10444 }
10445 change_state:
10446 /* For gain we must reach our target, all others last 1 rttProp */
10447 bbr_substate_change(bbr, cts, __LINE__, 1);
10448 }
10449
10450 static void
10451 bbr_set_probebw_gains(struct tcp_bbr *bbr, uint32_t cts, uint32_t losses)
10452 {
10453 uint32_t flight, bbr_cur_cycle_time;
10454
10455 if (bbr->rc_use_google) {
10456 bbr_set_probebw_google_gains(bbr, cts, losses);
10457 return;
10458 }
10459 if (cts == 0) {
10460 /*
10461 * Never alow cts to be 0 we
10462 * do this so we can judge if
10463 * we have set a timestamp.
10464 */
10465 cts = 1;
10466 }
10467 if (bbr_state_is_pkt_epoch)
10468 bbr_cur_cycle_time = bbr_get_rtt(bbr, BBR_RTT_PKTRTT);
10469 else
10470 bbr_cur_cycle_time = bbr_get_rtt(bbr, BBR_RTT_PROP);
10471
10472 if (bbr->r_ctl.rc_bbr_state_atflight == 0) {
10473 if (bbr_state_val(bbr) == BBR_SUB_DRAIN) {
10474 flight = ctf_flight_size(bbr->rc_tp,
10475 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
10476 if (bbr_sub_drain_slam_cwnd && bbr->rc_hit_state_1) {
10477 /* Keep it slam down */
10478 if (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state) {
10479 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state;
10480 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
10481 }
10482 if (bbr_sub_drain_app_limit) {
10483 /* Go app limited if we are on a long drain */
10484 bbr->r_ctl.r_app_limited_until = (bbr->r_ctl.rc_delivered + flight);
10485 }
10486 }
10487 if (TSTMP_GT(cts, bbr->r_ctl.gain_epoch) &&
10488 (((cts - bbr->r_ctl.gain_epoch) > bbr_get_rtt(bbr, BBR_RTT_PROP)) ||
10489 (flight >= bbr->r_ctl.flightsize_at_drain))) {
10490 /*
10491 * Still here after the same time as
10492 * the gain. We need to drain harder
10493 * for the next srtt. Reduce by a set amount
10494 * the gain drop is capped at DRAIN states
10495 * value (88).
10496 */
10497 bbr->r_ctl.flightsize_at_drain = flight;
10498 if (bbr_drain_drop_mul &&
10499 bbr_drain_drop_div &&
10500 (bbr_drain_drop_mul < bbr_drain_drop_div)) {
10501 /* Use your specific drop value (def 4/5 = 20%) */
10502 bbr->r_ctl.rc_bbr_hptsi_gain *= bbr_drain_drop_mul;
10503 bbr->r_ctl.rc_bbr_hptsi_gain /= bbr_drain_drop_div;
10504 } else {
10505 /* You get drop of 20% */
10506 bbr->r_ctl.rc_bbr_hptsi_gain *= 4;
10507 bbr->r_ctl.rc_bbr_hptsi_gain /= 5;
10508 }
10509 if (bbr->r_ctl.rc_bbr_hptsi_gain <= bbr_drain_floor) {
10510 /* Reduce our gain again to the bottom */
10511 bbr->r_ctl.rc_bbr_hptsi_gain = max(bbr_drain_floor, 1);
10512 }
10513 bbr_log_exit_gain(bbr, cts, 4);
10514 /*
10515 * Extend out so we wait another
10516 * epoch before dropping again.
10517 */
10518 bbr->r_ctl.gain_epoch = cts;
10519 }
10520 if (flight <= bbr->r_ctl.rc_target_at_state) {
10521 if (bbr_sub_drain_slam_cwnd &&
10522 (bbr->rc_use_google == 0) &&
10523 (bbr->rc_tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd)) {
10524 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd;
10525 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
10526 }
10527 bbr->r_ctl.rc_bbr_state_atflight = max(cts, 1);
10528 bbr_log_exit_gain(bbr, cts, 3);
10529 }
10530 } else {
10531 /* Its a gain */
10532 if (bbr->r_ctl.rc_lost > bbr->r_ctl.bbr_lost_at_state) {
10533 bbr->r_ctl.rc_bbr_state_atflight = max(cts, 1);
10534 goto change_state;
10535 }
10536 if ((ctf_outstanding(bbr->rc_tp) >= bbr->r_ctl.rc_target_at_state) ||
10537 ((ctf_outstanding(bbr->rc_tp) + bbr->rc_tp->t_maxseg - 1) >=
10538 bbr->rc_tp->snd_wnd)) {
10539 bbr->r_ctl.rc_bbr_state_atflight = max(cts, 1);
10540 bbr_log_exit_gain(bbr, cts, 2);
10541 }
10542 }
10543 /**
10544 * We fall through and return always one of two things has
10545 * occurred.
10546 * 1) We are still not at target
10547 * <or>
10548 * 2) We reached the target and set rc_bbr_state_atflight
10549 * which means we no longer hit this block
10550 * next time we are called.
10551 */
10552 return;
10553 }
10554 change_state:
10555 if (TSTMP_LT(cts, bbr->r_ctl.rc_bbr_state_time))
10556 return;
10557 if ((cts - bbr->r_ctl.rc_bbr_state_time) < bbr_cur_cycle_time) {
10558 /* Less than a full time-period has passed */
10559 return;
10560 }
10561 if (bbr->r_ctl.rc_level_state_extra &&
10562 (bbr_state_val(bbr) > BBR_SUB_DRAIN) &&
10563 ((cts - bbr->r_ctl.rc_bbr_state_time) <
10564 (bbr_cur_cycle_time + bbr->r_ctl.rc_level_state_extra))) {
10565 /* Less than a full time-period + extra has passed */
10566 return;
10567 }
10568 if (bbr_gain_gets_extra_too &&
10569 bbr->r_ctl.rc_level_state_extra &&
10570 (bbr_state_val(bbr) == BBR_SUB_GAIN) &&
10571 ((cts - bbr->r_ctl.rc_bbr_state_time) <
10572 (bbr_cur_cycle_time + bbr->r_ctl.rc_level_state_extra))) {
10573 /* Less than a full time-period + extra has passed */
10574 return;
10575 }
10576 bbr_substate_change(bbr, cts, __LINE__, 1);
10577 }
10578
10579 static uint32_t
10580 bbr_get_a_state_target(struct tcp_bbr *bbr, uint32_t gain)
10581 {
10582 uint32_t mss, tar;
10583
10584 if (bbr->rc_use_google) {
10585 /* Google just uses the cwnd target */
10586 tar = bbr_get_target_cwnd(bbr, bbr_get_bw(bbr), gain);
10587 } else {
10588 mss = min((bbr->rc_tp->t_maxseg - bbr->rc_last_options),
10589 bbr->r_ctl.rc_pace_max_segs);
10590 /* Get the base cwnd with gain rounded to a mss */
10591 tar = roundup(bbr_get_raw_target_cwnd(bbr, bbr_get_bw(bbr),
10592 gain), mss);
10593 /* Make sure it is within our min */
10594 if (tar < get_min_cwnd(bbr))
10595 return (get_min_cwnd(bbr));
10596 }
10597 return (tar);
10598 }
10599
10600 static void
10601 bbr_set_state_target(struct tcp_bbr *bbr, int line)
10602 {
10603 uint32_t tar, meth;
10604
10605 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) &&
10606 ((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google)) {
10607 /* Special case using old probe-rtt method */
10608 tar = bbr_rtt_probe_cwndtarg * (bbr->rc_tp->t_maxseg - bbr->rc_last_options);
10609 meth = 1;
10610 } else {
10611 /* Non-probe-rtt case and reduced probe-rtt */
10612 if ((bbr->rc_bbr_state == BBR_STATE_PROBE_BW) &&
10613 (bbr->r_ctl.rc_bbr_hptsi_gain > BBR_UNIT)) {
10614 /* For gain cycle we use the hptsi gain */
10615 tar = bbr_get_a_state_target(bbr, bbr->r_ctl.rc_bbr_hptsi_gain);
10616 meth = 2;
10617 } else if ((bbr_target_is_bbunit) || bbr->rc_use_google) {
10618 /*
10619 * If configured, or for google all other states
10620 * get BBR_UNIT.
10621 */
10622 tar = bbr_get_a_state_target(bbr, BBR_UNIT);
10623 meth = 3;
10624 } else {
10625 /*
10626 * Or we set a target based on the pacing gain
10627 * for non-google mode and default (non-configured).
10628 * Note we don't set a target goal below drain (192).
10629 */
10630 if (bbr->r_ctl.rc_bbr_hptsi_gain < bbr_hptsi_gain[BBR_SUB_DRAIN]) {
10631 tar = bbr_get_a_state_target(bbr, bbr_hptsi_gain[BBR_SUB_DRAIN]);
10632 meth = 4;
10633 } else {
10634 tar = bbr_get_a_state_target(bbr, bbr->r_ctl.rc_bbr_hptsi_gain);
10635 meth = 5;
10636 }
10637 }
10638 }
10639 bbr_log_set_of_state_target(bbr, tar, line, meth);
10640 bbr->r_ctl.rc_target_at_state = tar;
10641 }
10642
10643 static void
10644 bbr_enter_probe_rtt(struct tcp_bbr *bbr, uint32_t cts, int32_t line)
10645 {
10646 /* Change to probe_rtt */
10647 uint32_t time_in;
10648
10649 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost;
10650 bbr->r_ctl.flightsize_at_drain = ctf_flight_size(bbr->rc_tp,
10651 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
10652 bbr->r_ctl.r_app_limited_until = (bbr->r_ctl.flightsize_at_drain
10653 + bbr->r_ctl.rc_delivered);
10654 /* Setup so we force feed the filter */
10655 if (bbr->rc_use_google || bbr_probertt_sets_rtt)
10656 bbr->rc_prtt_set_ts = 1;
10657 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) {
10658 time_in = cts - bbr->r_ctl.rc_bbr_state_time;
10659 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in);
10660 }
10661 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_ENTERPROBE, 0);
10662 bbr->r_ctl.rc_rtt_shrinks = cts;
10663 bbr->r_ctl.last_in_probertt = cts;
10664 bbr->r_ctl.rc_probertt_srttchktim = cts;
10665 bbr->r_ctl.rc_bbr_state_time = cts;
10666 bbr->rc_bbr_state = BBR_STATE_PROBE_RTT;
10667 /* We need to force the filter to update */
10668
10669 if ((bbr_sub_drain_slam_cwnd) &&
10670 bbr->rc_hit_state_1 &&
10671 (bbr->rc_use_google == 0) &&
10672 (bbr_state_val(bbr) == BBR_SUB_DRAIN)) {
10673 if (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_saved_cwnd)
10674 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd;
10675 } else
10676 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd;
10677 /* Update the lost */
10678 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost;
10679 if ((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google){
10680 /* Set to the non-configurable default of 4 (PROBE_RTT_MIN) */
10681 bbr->rc_tp->snd_cwnd = bbr_rtt_probe_cwndtarg * (bbr->rc_tp->t_maxseg - bbr->rc_last_options);
10682 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
10683 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT;
10684 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT;
10685 bbr_log_set_of_state_target(bbr, bbr->rc_tp->snd_cwnd, __LINE__, 6);
10686 bbr->r_ctl.rc_target_at_state = bbr->rc_tp->snd_cwnd;
10687 } else {
10688 /*
10689 * We bring it down slowly by using a hptsi gain that is
10690 * probably 75%. This will slowly float down our outstanding
10691 * without tampering with the cwnd.
10692 */
10693 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.bbr_rttprobe_gain_val;
10694 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT;
10695 bbr_set_state_target(bbr, __LINE__);
10696 if (bbr_prtt_slam_cwnd &&
10697 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) {
10698 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state;
10699 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
10700 }
10701 }
10702 if (ctf_flight_size(bbr->rc_tp,
10703 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) <=
10704 bbr->r_ctl.rc_target_at_state) {
10705 /* We are at target */
10706 bbr->r_ctl.rc_bbr_enters_probertt = cts;
10707 } else {
10708 /* We need to come down to reach target before our time begins */
10709 bbr->r_ctl.rc_bbr_enters_probertt = 0;
10710 }
10711 bbr->r_ctl.rc_pe_of_prtt = bbr->r_ctl.rc_pkt_epoch;
10712 BBR_STAT_INC(bbr_enter_probertt);
10713 bbr_log_exit_gain(bbr, cts, 0);
10714 bbr_log_type_statechange(bbr, cts, line);
10715 }
10716
10717 static void
10718 bbr_check_probe_rtt_limits(struct tcp_bbr *bbr, uint32_t cts)
10719 {
10720 /*
10721 * Sanity check on probe-rtt intervals.
10722 * In crazy situations where we are competing
10723 * against new-reno flows with huge buffers
10724 * our rtt-prop interval could come to dominate
10725 * things if we can't get through a full set
10726 * of cycles, we need to adjust it.
10727 */
10728 if (bbr_can_adjust_probertt &&
10729 (bbr->rc_use_google == 0)) {
10730 uint16_t val = 0;
10731 uint32_t cur_rttp, fval, newval, baseval;
10732
10733 /* Are we to small and go into probe-rtt to often? */
10734 baseval = (bbr_get_rtt(bbr, BBR_RTT_PROP) * (BBR_SUBSTATE_COUNT + 1));
10735 cur_rttp = roundup(baseval, USECS_IN_SECOND);
10736 fval = bbr_filter_len_sec * USECS_IN_SECOND;
10737 if (bbr_is_ratio == 0) {
10738 if (fval > bbr_rtt_probe_limit)
10739 newval = cur_rttp + (fval - bbr_rtt_probe_limit);
10740 else
10741 newval = cur_rttp;
10742 } else {
10743 int mul;
10744
10745 mul = fval / bbr_rtt_probe_limit;
10746 newval = cur_rttp * mul;
10747 }
10748 if (cur_rttp > bbr->r_ctl.rc_probertt_int) {
10749 bbr->r_ctl.rc_probertt_int = cur_rttp;
10750 reset_time_small(&bbr->r_ctl.rc_rttprop, newval);
10751 val = 1;
10752 } else {
10753 /*
10754 * No adjustments were made
10755 * do we need to shrink it?
10756 */
10757 if (bbr->r_ctl.rc_probertt_int > bbr_rtt_probe_limit) {
10758 if (cur_rttp <= bbr_rtt_probe_limit) {
10759 /*
10760 * Things have calmed down lets
10761 * shrink all the way to default
10762 */
10763 bbr->r_ctl.rc_probertt_int = bbr_rtt_probe_limit;
10764 reset_time_small(&bbr->r_ctl.rc_rttprop,
10765 (bbr_filter_len_sec * USECS_IN_SECOND));
10766 cur_rttp = bbr_rtt_probe_limit;
10767 newval = (bbr_filter_len_sec * USECS_IN_SECOND);
10768 val = 2;
10769 } else {
10770 /*
10771 * Well does some adjustment make sense?
10772 */
10773 if (cur_rttp < bbr->r_ctl.rc_probertt_int) {
10774 /* We can reduce interval time some */
10775 bbr->r_ctl.rc_probertt_int = cur_rttp;
10776 reset_time_small(&bbr->r_ctl.rc_rttprop, newval);
10777 val = 3;
10778 }
10779 }
10780 }
10781 }
10782 if (val)
10783 bbr_log_rtt_shrinks(bbr, cts, cur_rttp, newval, __LINE__, BBR_RTTS_RESETS_VALUES, val);
10784 }
10785 }
10786
10787 static void
10788 bbr_exit_probe_rtt(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t cts)
10789 {
10790 /* Exit probe-rtt */
10791
10792 if (tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd) {
10793 tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd;
10794 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
10795 }
10796 bbr_log_exit_gain(bbr, cts, 1);
10797 bbr->rc_hit_state_1 = 0;
10798 bbr->r_ctl.rc_rtt_shrinks = cts;
10799 bbr->r_ctl.last_in_probertt = cts;
10800 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_RTTPROBE, 0);
10801 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost;
10802 bbr->r_ctl.r_app_limited_until = (ctf_flight_size(tp,
10803 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) +
10804 bbr->r_ctl.rc_delivered);
10805 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) {
10806 uint32_t time_in;
10807
10808 time_in = cts - bbr->r_ctl.rc_bbr_state_time;
10809 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in);
10810 }
10811 if (bbr->rc_filled_pipe) {
10812 /* Switch to probe_bw */
10813 bbr->rc_bbr_state = BBR_STATE_PROBE_BW;
10814 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts);
10815 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_cwnd_gain;
10816 bbr_substate_change(bbr, cts, __LINE__, 0);
10817 bbr_log_type_statechange(bbr, cts, __LINE__);
10818 } else {
10819 /* Back to startup */
10820 bbr->rc_bbr_state = BBR_STATE_STARTUP;
10821 bbr->r_ctl.rc_bbr_state_time = cts;
10822 /*
10823 * We don't want to give a complete free 3
10824 * measurements until we exit, so we use
10825 * the number of pe's we were in probe-rtt
10826 * to add to the startup_epoch. That way
10827 * we will still retain the old state.
10828 */
10829 bbr->r_ctl.rc_bbr_last_startup_epoch += (bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_pe_of_prtt);
10830 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost;
10831 /* Make sure to use the lower pg when shifting back in */
10832 if (bbr->r_ctl.rc_lost &&
10833 bbr_use_lower_gain_in_startup &&
10834 (bbr->rc_use_google == 0))
10835 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_startup_lower;
10836 else
10837 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_startup_pg;
10838 bbr->r_ctl.rc_bbr_cwnd_gain = bbr->r_ctl.rc_startup_pg;
10839 /* Probably not needed but set it anyway */
10840 bbr_set_state_target(bbr, __LINE__);
10841 bbr_log_type_statechange(bbr, cts, __LINE__);
10842 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch,
10843 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 0);
10844 }
10845 bbr_check_probe_rtt_limits(bbr, cts);
10846 }
10847
10848 static int32_t inline
10849 bbr_should_enter_probe_rtt(struct tcp_bbr *bbr, uint32_t cts)
10850 {
10851 if ((bbr->rc_past_init_win == 1) &&
10852 (bbr->rc_in_persist == 0) &&
10853 (bbr_calc_time(cts, bbr->r_ctl.rc_rtt_shrinks) >= bbr->r_ctl.rc_probertt_int)) {
10854 return (1);
10855 }
10856 if (bbr_can_force_probertt &&
10857 (bbr->rc_in_persist == 0) &&
10858 (TSTMP_GT(cts, bbr->r_ctl.last_in_probertt)) &&
10859 ((cts - bbr->r_ctl.last_in_probertt) > bbr->r_ctl.rc_probertt_int)) {
10860 return (1);
10861 }
10862 return (0);
10863 }
10864
10865 static int32_t
10866 bbr_google_startup(struct tcp_bbr *bbr, uint32_t cts, int32_t pkt_epoch)
10867 {
10868 uint64_t btlbw, gain;
10869 if (pkt_epoch == 0) {
10870 /*
10871 * Need to be on a pkt-epoch to continue.
10872 */
10873 return (0);
10874 }
10875 btlbw = bbr_get_full_bw(bbr);
10876 gain = ((bbr->r_ctl.rc_bbr_lastbtlbw *
10877 (uint64_t)bbr_start_exit) / (uint64_t)100) + bbr->r_ctl.rc_bbr_lastbtlbw;
10878 if (btlbw >= gain) {
10879 bbr->r_ctl.rc_bbr_last_startup_epoch = bbr->r_ctl.rc_pkt_epoch;
10880 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch,
10881 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 3);
10882 bbr->r_ctl.rc_bbr_lastbtlbw = btlbw;
10883 }
10884 if ((bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_bbr_last_startup_epoch) >= BBR_STARTUP_EPOCHS)
10885 return (1);
10886 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch,
10887 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 8);
10888 return(0);
10889 }
10890
10891 static int32_t inline
10892 bbr_state_startup(struct tcp_bbr *bbr, uint32_t cts, int32_t epoch, int32_t pkt_epoch)
10893 {
10894 /* Have we gained 25% in the last 3 packet based epoch's? */
10895 uint64_t btlbw, gain;
10896 int do_exit;
10897 int delta, rtt_gain;
10898
10899 if ((bbr->rc_tp->snd_una == bbr->rc_tp->snd_max) &&
10900 (bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time) >= bbr_rtt_probe_time)) {
10901 /*
10902 * This qualifies as a RTT_PROBE session since we drop the
10903 * data outstanding to nothing and waited more than
10904 * bbr_rtt_probe_time.
10905 */
10906 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_WASIDLE, 0);
10907 bbr_set_reduced_rtt(bbr, cts, __LINE__);
10908 }
10909 if (bbr_should_enter_probe_rtt(bbr, cts)) {
10910 bbr_enter_probe_rtt(bbr, cts, __LINE__);
10911 return (0);
10912 }
10913 if (bbr->rc_use_google)
10914 return (bbr_google_startup(bbr, cts, pkt_epoch));
10915
10916 if ((bbr->r_ctl.rc_lost > bbr->r_ctl.rc_lost_at_startup) &&
10917 (bbr_use_lower_gain_in_startup)) {
10918 /* Drop to a lower gain 1.5 x since we saw loss */
10919 bbr->r_ctl.rc_bbr_hptsi_gain = bbr_startup_lower;
10920 }
10921 if (pkt_epoch == 0) {
10922 /*
10923 * Need to be on a pkt-epoch to continue.
10924 */
10925 return (0);
10926 }
10927 if (bbr_rtt_gain_thresh) {
10928 /*
10929 * Do we allow a flow to stay
10930 * in startup with no loss and no
10931 * gain in rtt over a set threshold?
10932 */
10933 if (bbr->r_ctl.rc_pkt_epoch_rtt &&
10934 bbr->r_ctl.startup_last_srtt &&
10935 (bbr->r_ctl.rc_pkt_epoch_rtt > bbr->r_ctl.startup_last_srtt)) {
10936 delta = bbr->r_ctl.rc_pkt_epoch_rtt - bbr->r_ctl.startup_last_srtt;
10937 rtt_gain = (delta * 100) / bbr->r_ctl.startup_last_srtt;
10938 } else
10939 rtt_gain = 0;
10940 if ((bbr->r_ctl.startup_last_srtt == 0) ||
10941 (bbr->r_ctl.rc_pkt_epoch_rtt < bbr->r_ctl.startup_last_srtt))
10942 /* First time or new lower value */
10943 bbr->r_ctl.startup_last_srtt = bbr->r_ctl.rc_pkt_epoch_rtt;
10944
10945 if ((bbr->r_ctl.rc_lost == 0) &&
10946 (rtt_gain < bbr_rtt_gain_thresh)) {
10947 /*
10948 * No loss, and we are under
10949 * our gain threhold for
10950 * increasing RTT.
10951 */
10952 if (bbr->r_ctl.rc_bbr_last_startup_epoch < bbr->r_ctl.rc_pkt_epoch)
10953 bbr->r_ctl.rc_bbr_last_startup_epoch++;
10954 bbr_log_startup_event(bbr, cts, rtt_gain,
10955 delta, bbr->r_ctl.startup_last_srtt, 10);
10956 return (0);
10957 }
10958 }
10959 if ((bbr->r_ctl.r_measurement_count == bbr->r_ctl.last_startup_measure) &&
10960 (bbr->r_ctl.rc_lost_at_startup == bbr->r_ctl.rc_lost) &&
10961 (!IN_RECOVERY(bbr->rc_tp->t_flags))) {
10962 /*
10963 * We only assess if we have a new measurement when
10964 * we have no loss and are not in recovery.
10965 * Drag up by one our last_startup epoch so we will hold
10966 * the number of non-gain we have already accumulated.
10967 */
10968 if (bbr->r_ctl.rc_bbr_last_startup_epoch < bbr->r_ctl.rc_pkt_epoch)
10969 bbr->r_ctl.rc_bbr_last_startup_epoch++;
10970 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch,
10971 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 9);
10972 return (0);
10973 }
10974 /* Case where we reduced the lost (bad retransmit) */
10975 if (bbr->r_ctl.rc_lost_at_startup > bbr->r_ctl.rc_lost)
10976 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost;
10977 bbr->r_ctl.last_startup_measure = bbr->r_ctl.r_measurement_count;
10978 btlbw = bbr_get_full_bw(bbr);
10979 if (bbr->r_ctl.rc_bbr_hptsi_gain == bbr_startup_lower)
10980 gain = ((bbr->r_ctl.rc_bbr_lastbtlbw *
10981 (uint64_t)bbr_low_start_exit) / (uint64_t)100) + bbr->r_ctl.rc_bbr_lastbtlbw;
10982 else
10983 gain = ((bbr->r_ctl.rc_bbr_lastbtlbw *
10984 (uint64_t)bbr_start_exit) / (uint64_t)100) + bbr->r_ctl.rc_bbr_lastbtlbw;
10985 do_exit = 0;
10986 if (btlbw > bbr->r_ctl.rc_bbr_lastbtlbw)
10987 bbr->r_ctl.rc_bbr_lastbtlbw = btlbw;
10988 if (btlbw >= gain) {
10989 bbr->r_ctl.rc_bbr_last_startup_epoch = bbr->r_ctl.rc_pkt_epoch;
10990 /* Update the lost so we won't exit in next set of tests */
10991 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost;
10992 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch,
10993 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 3);
10994 }
10995 if ((bbr->rc_loss_exit &&
10996 (bbr->r_ctl.rc_lost > bbr->r_ctl.rc_lost_at_startup) &&
10997 (bbr->r_ctl.rc_pkt_epoch_loss_rate > bbr_startup_loss_thresh)) &&
10998 ((bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_bbr_last_startup_epoch) >= BBR_STARTUP_EPOCHS)) {
10999 /*
11000 * If we had no gain, we had loss and that loss was above
11001 * our threshould, the rwnd is not constrained, and we have
11002 * had at least 3 packet epochs exit. Note that this is
11003 * switched off by sysctl. Google does not do this by the
11004 * way.
11005 */
11006 if ((ctf_flight_size(bbr->rc_tp,
11007 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) +
11008 (2 * max(bbr->r_ctl.rc_pace_max_segs, bbr->rc_tp->t_maxseg))) <= bbr->rc_tp->snd_wnd) {
11009 do_exit = 1;
11010 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch,
11011 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 4);
11012 } else {
11013 /* Just record an updated loss value */
11014 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost;
11015 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch,
11016 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 5);
11017 }
11018 } else
11019 bbr->r_ctl.rc_lost_at_startup = bbr->r_ctl.rc_lost;
11020 if (((bbr->r_ctl.rc_pkt_epoch - bbr->r_ctl.rc_bbr_last_startup_epoch) >= BBR_STARTUP_EPOCHS) ||
11021 do_exit) {
11022 /* Return 1 to exit the startup state. */
11023 return (1);
11024 }
11025 /* Stay in startup */
11026 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch,
11027 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 8);
11028 return (0);
11029 }
11030
11031 static void
11032 bbr_state_change(struct tcp_bbr *bbr, uint32_t cts, int32_t epoch, int32_t pkt_epoch, uint32_t losses)
11033 {
11034 /*
11035 * A tick occurred in the rtt epoch do we need to do anything?
11036 */
11037 #ifdef BBR_INVARIANTS
11038 if ((bbr->rc_bbr_state != BBR_STATE_STARTUP) &&
11039 (bbr->rc_bbr_state != BBR_STATE_DRAIN) &&
11040 (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) &&
11041 (bbr->rc_bbr_state != BBR_STATE_IDLE_EXIT) &&
11042 (bbr->rc_bbr_state != BBR_STATE_PROBE_BW)) {
11043 /* Debug code? */
11044 panic("Unknown BBR state %d?\n", bbr->rc_bbr_state);
11045 }
11046 #endif
11047 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) {
11048 /* Do we exit the startup state? */
11049 if (bbr_state_startup(bbr, cts, epoch, pkt_epoch)) {
11050 uint32_t time_in;
11051
11052 bbr_log_startup_event(bbr, cts, bbr->r_ctl.rc_bbr_last_startup_epoch,
11053 bbr->r_ctl.rc_lost_at_startup, bbr_start_exit, 6);
11054 bbr->rc_filled_pipe = 1;
11055 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost;
11056 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) {
11057 time_in = cts - bbr->r_ctl.rc_bbr_state_time;
11058 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in);
11059 } else
11060 time_in = 0;
11061 if (bbr->rc_no_pacing)
11062 bbr->rc_no_pacing = 0;
11063 bbr->r_ctl.rc_bbr_state_time = cts;
11064 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.rc_drain_pg;
11065 bbr->rc_bbr_state = BBR_STATE_DRAIN;
11066 bbr_set_state_target(bbr, __LINE__);
11067 if ((bbr->rc_use_google == 0) &&
11068 bbr_slam_cwnd_in_main_drain) {
11069 /* Here we don't have to worry about probe-rtt */
11070 bbr->r_ctl.rc_saved_cwnd = bbr->rc_tp->snd_cwnd;
11071 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state;
11072 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
11073 }
11074 bbr->r_ctl.rc_bbr_cwnd_gain = bbr_high_gain;
11075 bbr_log_type_statechange(bbr, cts, __LINE__);
11076 if (ctf_flight_size(bbr->rc_tp,
11077 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes)) <=
11078 bbr->r_ctl.rc_target_at_state) {
11079 /*
11080 * Switch to probe_bw if we are already
11081 * there
11082 */
11083 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts);
11084 bbr_substate_change(bbr, cts, __LINE__, 0);
11085 bbr->rc_bbr_state = BBR_STATE_PROBE_BW;
11086 bbr_log_type_statechange(bbr, cts, __LINE__);
11087 }
11088 }
11089 } else if (bbr->rc_bbr_state == BBR_STATE_IDLE_EXIT) {
11090 uint32_t inflight;
11091 struct tcpcb *tp;
11092
11093 tp = bbr->rc_tp;
11094 inflight = ctf_flight_size(tp,
11095 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
11096 if (inflight >= bbr->r_ctl.rc_target_at_state) {
11097 /* We have reached a flight of the cwnd target */
11098 bbr->rc_bbr_state = BBR_STATE_PROBE_BW;
11099 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT;
11100 bbr->r_ctl.rc_bbr_cwnd_gain = BBR_UNIT;
11101 bbr_set_state_target(bbr, __LINE__);
11102 /*
11103 * Rig it so we don't do anything crazy and
11104 * start fresh with a new randomization.
11105 */
11106 bbr->r_ctl.bbr_smallest_srtt_this_state = 0xffffffff;
11107 bbr->rc_bbr_substate = BBR_SUB_LEVEL6;
11108 bbr_substate_change(bbr, cts, __LINE__, 1);
11109 }
11110 } else if (bbr->rc_bbr_state == BBR_STATE_DRAIN) {
11111 /* Has in-flight reached the bdp (or less)? */
11112 uint32_t inflight;
11113 struct tcpcb *tp;
11114
11115 tp = bbr->rc_tp;
11116 inflight = ctf_flight_size(tp,
11117 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
11118 if ((bbr->rc_use_google == 0) &&
11119 bbr_slam_cwnd_in_main_drain &&
11120 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) {
11121 /*
11122 * Here we don't have to worry about probe-rtt
11123 * re-slam it, but keep it slammed down.
11124 */
11125 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state;
11126 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
11127 }
11128 if (inflight <= bbr->r_ctl.rc_target_at_state) {
11129 /* We have drained */
11130 bbr->rc_bbr_state = BBR_STATE_PROBE_BW;
11131 bbr->r_ctl.bbr_lost_at_state = bbr->r_ctl.rc_lost;
11132 if (SEQ_GT(cts, bbr->r_ctl.rc_bbr_state_time)) {
11133 uint32_t time_in;
11134
11135 time_in = cts - bbr->r_ctl.rc_bbr_state_time;
11136 counter_u64_add(bbr_state_time[bbr->rc_bbr_state], time_in);
11137 }
11138 if ((bbr->rc_use_google == 0) &&
11139 bbr_slam_cwnd_in_main_drain &&
11140 (tp->snd_cwnd < bbr->r_ctl.rc_saved_cwnd)) {
11141 /* Restore the cwnd */
11142 tp->snd_cwnd = bbr->r_ctl.rc_saved_cwnd;
11143 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
11144 }
11145 /* Setup probe-rtt has being done now RRS-HERE */
11146 bbr->r_ctl.rc_rtt_shrinks = cts;
11147 bbr->r_ctl.last_in_probertt = cts;
11148 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_LEAVE_DRAIN, 0);
11149 /* Randomly pick a sub-state */
11150 bbr->rc_bbr_substate = bbr_pick_probebw_substate(bbr, cts);
11151 bbr_substate_change(bbr, cts, __LINE__, 0);
11152 bbr_log_type_statechange(bbr, cts, __LINE__);
11153 }
11154 } else if (bbr->rc_bbr_state == BBR_STATE_PROBE_RTT) {
11155 uint32_t flight;
11156
11157 flight = ctf_flight_size(bbr->rc_tp,
11158 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
11159 bbr->r_ctl.r_app_limited_until = (flight + bbr->r_ctl.rc_delivered);
11160 if (((bbr->r_ctl.bbr_rttprobe_gain_val == 0) || bbr->rc_use_google) &&
11161 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) {
11162 /*
11163 * We must keep cwnd at the desired MSS.
11164 */
11165 bbr->rc_tp->snd_cwnd = bbr_rtt_probe_cwndtarg * (bbr->rc_tp->t_maxseg - bbr->rc_last_options);
11166 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
11167 } else if ((bbr_prtt_slam_cwnd) &&
11168 (bbr->rc_tp->snd_cwnd > bbr->r_ctl.rc_target_at_state)) {
11169 /* Re-slam it */
11170 bbr->rc_tp->snd_cwnd = bbr->r_ctl.rc_target_at_state;
11171 bbr_log_type_cwndupd(bbr, 0, 0, 0, 12, 0, 0, __LINE__);
11172 }
11173 if (bbr->r_ctl.rc_bbr_enters_probertt == 0) {
11174 /* Has outstanding reached our target? */
11175 if (flight <= bbr->r_ctl.rc_target_at_state) {
11176 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_REACHTAR, 0);
11177 bbr->r_ctl.rc_bbr_enters_probertt = cts;
11178 /* If time is exactly 0, be 1usec off */
11179 if (bbr->r_ctl.rc_bbr_enters_probertt == 0)
11180 bbr->r_ctl.rc_bbr_enters_probertt = 1;
11181 if (bbr->rc_use_google == 0) {
11182 /*
11183 * Restore any lowering that as occurred to
11184 * reach here
11185 */
11186 if (bbr->r_ctl.bbr_rttprobe_gain_val)
11187 bbr->r_ctl.rc_bbr_hptsi_gain = bbr->r_ctl.bbr_rttprobe_gain_val;
11188 else
11189 bbr->r_ctl.rc_bbr_hptsi_gain = BBR_UNIT;
11190 }
11191 }
11192 if ((bbr->r_ctl.rc_bbr_enters_probertt == 0) &&
11193 (bbr->rc_use_google == 0) &&
11194 bbr->r_ctl.bbr_rttprobe_gain_val &&
11195 (((cts - bbr->r_ctl.rc_probertt_srttchktim) > bbr_get_rtt(bbr, bbr_drain_rtt)) ||
11196 (flight >= bbr->r_ctl.flightsize_at_drain))) {
11197 /*
11198 * We have doddled with our current hptsi
11199 * gain an srtt and have still not made it
11200 * to target, or we have increased our flight.
11201 * Lets reduce the gain by xx%
11202 * flooring the reduce at DRAIN (based on
11203 * mul/div)
11204 */
11205 int red;
11206
11207 bbr->r_ctl.flightsize_at_drain = flight;
11208 bbr->r_ctl.rc_probertt_srttchktim = cts;
11209 red = max((bbr->r_ctl.bbr_rttprobe_gain_val / 10), 1);
11210 if ((bbr->r_ctl.rc_bbr_hptsi_gain - red) > max(bbr_drain_floor, 1)) {
11211 /* Reduce our gain again */
11212 bbr->r_ctl.rc_bbr_hptsi_gain -= red;
11213 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_SHRINK_PG, 0);
11214 } else if (bbr->r_ctl.rc_bbr_hptsi_gain > max(bbr_drain_floor, 1)) {
11215 /* one more chance before we give up */
11216 bbr->r_ctl.rc_bbr_hptsi_gain = max(bbr_drain_floor, 1);
11217 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_SHRINK_PG_FINAL, 0);
11218 } else {
11219 /* At the very bottom */
11220 bbr->r_ctl.rc_bbr_hptsi_gain = max((bbr_drain_floor-1), 1);
11221 }
11222 }
11223 }
11224 if (bbr->r_ctl.rc_bbr_enters_probertt &&
11225 (TSTMP_GT(cts, bbr->r_ctl.rc_bbr_enters_probertt)) &&
11226 ((cts - bbr->r_ctl.rc_bbr_enters_probertt) >= bbr_rtt_probe_time)) {
11227 /* Time to exit probe RTT normally */
11228 bbr_exit_probe_rtt(bbr->rc_tp, bbr, cts);
11229 }
11230 } else if (bbr->rc_bbr_state == BBR_STATE_PROBE_BW) {
11231 if ((bbr->rc_tp->snd_una == bbr->rc_tp->snd_max) &&
11232 (bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time) >= bbr_rtt_probe_time)) {
11233 /*
11234 * This qualifies as a RTT_PROBE session since we
11235 * drop the data outstanding to nothing and waited
11236 * more than bbr_rtt_probe_time.
11237 */
11238 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_WASIDLE, 0);
11239 bbr_set_reduced_rtt(bbr, cts, __LINE__);
11240 }
11241 if (bbr_should_enter_probe_rtt(bbr, cts)) {
11242 bbr_enter_probe_rtt(bbr, cts, __LINE__);
11243 } else {
11244 bbr_set_probebw_gains(bbr, cts, losses);
11245 }
11246 }
11247 }
11248
11249 static void
11250 bbr_check_bbr_for_state(struct tcp_bbr *bbr, uint32_t cts, int32_t line, uint32_t losses)
11251 {
11252 int32_t epoch = 0;
11253
11254 if ((cts - bbr->r_ctl.rc_rcv_epoch_start) >= bbr_get_rtt(bbr, BBR_RTT_PROP)) {
11255 bbr_set_epoch(bbr, cts, line);
11256 /* At each epoch doe lt bw sampling */
11257 epoch = 1;
11258 }
11259 bbr_state_change(bbr, cts, epoch, bbr->rc_is_pkt_epoch_now, losses);
11260 }
11261
11262 static int
11263 bbr_do_segment_nounlock(struct mbuf *m, struct tcphdr *th, struct socket *so,
11264 struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, uint8_t iptos,
11265 int32_t nxt_pkt, struct timeval *tv)
11266 {
11267 struct inpcb *inp = tptoinpcb(tp);
11268 int32_t thflags, retval;
11269 uint32_t cts, lcts;
11270 uint32_t tiwin;
11271 struct tcpopt to;
11272 struct tcp_bbr *bbr;
11273 struct bbr_sendmap *rsm;
11274 struct timeval ltv;
11275 int32_t did_out = 0;
11276 uint16_t nsegs;
11277 int32_t prev_state;
11278 uint32_t lost;
11279
11280 nsegs = max(1, m->m_pkthdr.lro_nsegs);
11281 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
11282 /* add in our stats */
11283 kern_prefetch(bbr, &prev_state);
11284 prev_state = 0;
11285 thflags = tcp_get_flags(th);
11286 /*
11287 * If this is either a state-changing packet or current state isn't
11288 * established, we require a write lock on tcbinfo. Otherwise, we
11289 * allow the tcbinfo to be in either alocked or unlocked, as the
11290 * caller may have unnecessarily acquired a write lock due to a
11291 * race.
11292 */
11293 INP_WLOCK_ASSERT(tptoinpcb(tp));
11294 KASSERT(tp->t_state > TCPS_LISTEN, ("%s: TCPS_LISTEN",
11295 __func__));
11296 KASSERT(tp->t_state != TCPS_TIME_WAIT, ("%s: TCPS_TIME_WAIT",
11297 __func__));
11298
11299 tp->t_rcvtime = ticks;
11300 /*
11301 * Unscale the window into a 32-bit value. For the SYN_SENT state
11302 * the scale is zero.
11303 */
11304 tiwin = th->th_win << tp->snd_scale;
11305 #ifdef STATS
11306 stats_voi_update_abs_ulong(tp->t_stats, VOI_TCP_FRWIN, tiwin);
11307 #endif
11308
11309 if (m->m_flags & M_TSTMP) {
11310 /* Prefer the hardware timestamp if present */
11311 struct timespec ts;
11312
11313 mbuf_tstmp2timespec(m, &ts);
11314 bbr->rc_tv.tv_sec = ts.tv_sec;
11315 bbr->rc_tv.tv_usec = ts.tv_nsec / 1000;
11316 bbr->r_ctl.rc_rcvtime = cts = tcp_tv_to_usectick(&bbr->rc_tv);
11317 } else if (m->m_flags & M_TSTMP_LRO) {
11318 /* Next the arrival timestamp */
11319 struct timespec ts;
11320
11321 mbuf_tstmp2timespec(m, &ts);
11322 bbr->rc_tv.tv_sec = ts.tv_sec;
11323 bbr->rc_tv.tv_usec = ts.tv_nsec / 1000;
11324 bbr->r_ctl.rc_rcvtime = cts = tcp_tv_to_usectick(&bbr->rc_tv);
11325 } else {
11326 /*
11327 * Ok just get the current time.
11328 */
11329 bbr->r_ctl.rc_rcvtime = lcts = cts = tcp_get_usecs(&bbr->rc_tv);
11330 }
11331 /*
11332 * Parse options on any incoming segment.
11333 */
11334 tcp_dooptions(&to, (u_char *)(th + 1),
11335 (th->th_off << 2) - sizeof(struct tcphdr),
11336 (thflags & TH_SYN) ? TO_SYN : 0);
11337
11338 /*
11339 * If timestamps were negotiated during SYN/ACK and a
11340 * segment without a timestamp is received, silently drop
11341 * the segment, unless it is a RST segment or missing timestamps are
11342 * tolerated.
11343 * See section 3.2 of RFC 7323.
11344 */
11345 if ((tp->t_flags & TF_RCVD_TSTMP) && !(to.to_flags & TOF_TS) &&
11346 ((thflags & TH_RST) == 0) && (V_tcp_tolerate_missing_ts == 0)) {
11347 retval = 0;
11348 m_freem(m);
11349 goto done_with_input;
11350 }
11351 /*
11352 * If echoed timestamp is later than the current time, fall back to
11353 * non RFC1323 RTT calculation. Normalize timestamp if syncookies
11354 * were used when this connection was established.
11355 */
11356 if ((to.to_flags & TOF_TS) && (to.to_tsecr != 0)) {
11357 to.to_tsecr -= tp->ts_offset;
11358 if (TSTMP_GT(to.to_tsecr, tcp_tv_to_mssectick(&bbr->rc_tv)))
11359 to.to_tsecr = 0;
11360 }
11361 /*
11362 * If its the first time in we need to take care of options and
11363 * verify we can do SACK for rack!
11364 */
11365 if (bbr->r_state == 0) {
11366 /*
11367 * Process options only when we get SYN/ACK back. The SYN
11368 * case for incoming connections is handled in tcp_syncache.
11369 * According to RFC1323 the window field in a SYN (i.e., a
11370 * <SYN> or <SYN,ACK>) segment itself is never scaled. XXX
11371 * this is traditional behavior, may need to be cleaned up.
11372 */
11373 if (bbr->rc_inp == NULL) {
11374 bbr->rc_inp = inp;
11375 }
11376 /*
11377 * We need to init rc_inp here since its not init'd when
11378 * bbr_init is called
11379 */
11380 if (tp->t_state == TCPS_SYN_SENT && (thflags & TH_SYN)) {
11381 if ((to.to_flags & TOF_SCALE) &&
11382 (tp->t_flags & TF_REQ_SCALE)) {
11383 tp->t_flags |= TF_RCVD_SCALE;
11384 tp->snd_scale = to.to_wscale;
11385 } else
11386 tp->t_flags &= ~TF_REQ_SCALE;
11387 /*
11388 * Initial send window. It will be updated with the
11389 * next incoming segment to the scaled value.
11390 */
11391 tp->snd_wnd = th->th_win;
11392 if ((to.to_flags & TOF_TS) &&
11393 (tp->t_flags & TF_REQ_TSTMP)) {
11394 tp->t_flags |= TF_RCVD_TSTMP;
11395 tp->ts_recent = to.to_tsval;
11396 tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv);
11397 } else
11398 tp->t_flags &= ~TF_REQ_TSTMP;
11399 if (to.to_flags & TOF_MSS)
11400 tcp_mss(tp, to.to_mss);
11401 if ((tp->t_flags & TF_SACK_PERMIT) &&
11402 (to.to_flags & TOF_SACKPERM) == 0)
11403 tp->t_flags &= ~TF_SACK_PERMIT;
11404 if (IS_FASTOPEN(tp->t_flags)) {
11405 if (to.to_flags & TOF_FASTOPEN) {
11406 uint16_t mss;
11407
11408 if (to.to_flags & TOF_MSS)
11409 mss = to.to_mss;
11410 else
11411 if ((inp->inp_vflag & INP_IPV6) != 0)
11412 mss = TCP6_MSS;
11413 else
11414 mss = TCP_MSS;
11415 tcp_fastopen_update_cache(tp, mss,
11416 to.to_tfo_len, to.to_tfo_cookie);
11417 } else
11418 tcp_fastopen_disable_path(tp);
11419 }
11420 }
11421 /*
11422 * At this point we are at the initial call. Here we decide
11423 * if we are doing RACK or not. We do this by seeing if
11424 * TF_SACK_PERMIT is set, if not rack is *not* possible and
11425 * we switch to the default code.
11426 */
11427 if ((tp->t_flags & TF_SACK_PERMIT) == 0) {
11428 /* Bail */
11429 tcp_switch_back_to_default(tp);
11430 (*tp->t_fb->tfb_tcp_do_segment) (m, th, so, tp, drop_hdrlen,
11431 tlen, iptos);
11432 return (1);
11433 }
11434 /* Set the flag */
11435 bbr->r_is_v6 = (inp->inp_vflag & INP_IPV6) != 0;
11436 tcp_set_hpts(inp);
11437 sack_filter_clear(&bbr->r_ctl.bbr_sf, th->th_ack);
11438 }
11439 if (thflags & TH_ACK) {
11440 /* Track ack types */
11441 if (to.to_flags & TOF_SACK)
11442 BBR_STAT_INC(bbr_acks_with_sacks);
11443 else
11444 BBR_STAT_INC(bbr_plain_acks);
11445 }
11446 /*
11447 * This is the one exception case where we set the rack state
11448 * always. All other times (timers etc) we must have a rack-state
11449 * set (so we assure we have done the checks above for SACK).
11450 */
11451 if (thflags & TH_FIN)
11452 tcp_log_end_status(tp, TCP_EI_STATUS_CLIENT_FIN);
11453 if (bbr->r_state != tp->t_state)
11454 bbr_set_state(tp, bbr, tiwin);
11455
11456 if (SEQ_GT(th->th_ack, tp->snd_una) && (rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map)) != NULL)
11457 kern_prefetch(rsm, &prev_state);
11458 prev_state = bbr->r_state;
11459 bbr->rc_ack_was_delayed = 0;
11460 lost = bbr->r_ctl.rc_lost;
11461 bbr->rc_is_pkt_epoch_now = 0;
11462 if (m->m_flags & (M_TSTMP|M_TSTMP_LRO)) {
11463 /* Get the real time into lcts and figure the real delay */
11464 lcts = tcp_get_usecs(<v);
11465 if (TSTMP_GT(lcts, cts)) {
11466 bbr->r_ctl.rc_ack_hdwr_delay = lcts - cts;
11467 bbr->rc_ack_was_delayed = 1;
11468 if (TSTMP_GT(bbr->r_ctl.rc_ack_hdwr_delay,
11469 bbr->r_ctl.highest_hdwr_delay))
11470 bbr->r_ctl.highest_hdwr_delay = bbr->r_ctl.rc_ack_hdwr_delay;
11471 } else {
11472 bbr->r_ctl.rc_ack_hdwr_delay = 0;
11473 bbr->rc_ack_was_delayed = 0;
11474 }
11475 } else {
11476 bbr->r_ctl.rc_ack_hdwr_delay = 0;
11477 bbr->rc_ack_was_delayed = 0;
11478 }
11479 bbr_log_ack_event(bbr, th, &to, tlen, nsegs, cts, nxt_pkt, m);
11480 if ((thflags & TH_SYN) && (thflags & TH_FIN) && V_drop_synfin) {
11481 retval = 0;
11482 m_freem(m);
11483 goto done_with_input;
11484 }
11485 /*
11486 * If a segment with the ACK-bit set arrives in the SYN-SENT state
11487 * check SEQ.ACK first as described on page 66 of RFC 793, section 3.9.
11488 */
11489 if ((tp->t_state == TCPS_SYN_SENT) && (thflags & TH_ACK) &&
11490 (SEQ_LEQ(th->th_ack, tp->iss) || SEQ_GT(th->th_ack, tp->snd_max))) {
11491 tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT);
11492 ctf_do_dropwithreset_conn(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
11493 return (1);
11494 }
11495 if (tiwin > bbr->r_ctl.rc_high_rwnd)
11496 bbr->r_ctl.rc_high_rwnd = tiwin;
11497 bbr->r_ctl.rc_flight_at_input = ctf_flight_size(tp,
11498 (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
11499 bbr->rtt_valid = 0;
11500 if (to.to_flags & TOF_TS) {
11501 bbr->rc_ts_valid = 1;
11502 bbr->r_ctl.last_inbound_ts = to.to_tsval;
11503 } else {
11504 bbr->rc_ts_valid = 0;
11505 bbr->r_ctl.last_inbound_ts = 0;
11506 }
11507 retval = (*bbr->r_substate) (m, th, so,
11508 tp, &to, drop_hdrlen,
11509 tlen, tiwin, thflags, nxt_pkt, iptos);
11510 if (nxt_pkt == 0)
11511 BBR_STAT_INC(bbr_rlock_left_ret0);
11512 else
11513 BBR_STAT_INC(bbr_rlock_left_ret1);
11514 if (retval == 0) {
11515 /*
11516 * If retval is 1 the tcb is unlocked and most likely the tp
11517 * is gone.
11518 */
11519 INP_WLOCK_ASSERT(inp);
11520 tcp_bbr_xmit_timer_commit(bbr, tp, cts);
11521 if (bbr->rc_is_pkt_epoch_now)
11522 bbr_set_pktepoch(bbr, cts, __LINE__);
11523 bbr_check_bbr_for_state(bbr, cts, __LINE__, (bbr->r_ctl.rc_lost - lost));
11524 if (nxt_pkt == 0) {
11525 if (bbr->r_wanted_output != 0) {
11526 bbr->rc_output_starts_timer = 0;
11527 did_out = 1;
11528 if (tcp_output(tp) < 0)
11529 return (1);
11530 } else
11531 bbr_start_hpts_timer(bbr, tp, cts, 6, 0, 0);
11532 }
11533 if ((nxt_pkt == 0) &&
11534 ((bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK) == 0) &&
11535 (SEQ_GT(tp->snd_max, tp->snd_una) ||
11536 (tp->t_flags & TF_DELACK) ||
11537 ((V_tcp_always_keepalive || bbr->rc_inp->inp_socket->so_options & SO_KEEPALIVE) &&
11538 (tp->t_state <= TCPS_CLOSING)))) {
11539 /*
11540 * We could not send (probably in the hpts but
11541 * stopped the timer)?
11542 */
11543 if ((tp->snd_max == tp->snd_una) &&
11544 ((tp->t_flags & TF_DELACK) == 0) &&
11545 (tcp_in_hpts(bbr->rc_inp)) &&
11546 (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) {
11547 /*
11548 * keep alive not needed if we are hptsi
11549 * output yet
11550 */
11551 ;
11552 } else {
11553 if (tcp_in_hpts(bbr->rc_inp)) {
11554 tcp_hpts_remove(bbr->rc_inp);
11555 if ((bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) &&
11556 (TSTMP_GT(lcts, bbr->rc_pacer_started))) {
11557 uint32_t del;
11558
11559 del = lcts - bbr->rc_pacer_started;
11560 if (bbr->r_ctl.rc_last_delay_val > del) {
11561 BBR_STAT_INC(bbr_force_timer_start);
11562 bbr->r_ctl.rc_last_delay_val -= del;
11563 bbr->rc_pacer_started = lcts;
11564 } else {
11565 /* We are late */
11566 bbr->r_ctl.rc_last_delay_val = 0;
11567 BBR_STAT_INC(bbr_force_output);
11568 if (tcp_output(tp) < 0)
11569 return (1);
11570 }
11571 }
11572 }
11573 bbr_start_hpts_timer(bbr, tp, cts, 8, bbr->r_ctl.rc_last_delay_val,
11574 0);
11575 }
11576 } else if ((bbr->rc_output_starts_timer == 0) && (nxt_pkt == 0)) {
11577 /* Do we have the correct timer running? */
11578 bbr_timer_audit(tp, bbr, lcts, &so->so_snd);
11579 }
11580 /* Do we have a new state */
11581 if (bbr->r_state != tp->t_state)
11582 bbr_set_state(tp, bbr, tiwin);
11583 done_with_input:
11584 bbr_log_doseg_done(bbr, cts, nxt_pkt, did_out);
11585 if (did_out)
11586 bbr->r_wanted_output = 0;
11587 }
11588 return (retval);
11589 }
11590
11591 static void
11592 bbr_do_segment(struct mbuf *m, struct tcphdr *th, struct socket *so,
11593 struct tcpcb *tp, int32_t drop_hdrlen, int32_t tlen, uint8_t iptos)
11594 {
11595 struct timeval tv;
11596 int retval;
11597
11598 /* First lets see if we have old packets */
11599 if (tp->t_in_pkt) {
11600 if (ctf_do_queued_segments(so, tp, 1)) {
11601 m_freem(m);
11602 return;
11603 }
11604 }
11605 if (m->m_flags & M_TSTMP_LRO) {
11606 mbuf_tstmp2timeval(m, &tv);
11607 } else {
11608 /* Should not be should we kassert instead? */
11609 tcp_get_usecs(&tv);
11610 }
11611 retval = bbr_do_segment_nounlock(m, th, so, tp,
11612 drop_hdrlen, tlen, iptos, 0, &tv);
11613 if (retval == 0) {
11614 INP_WUNLOCK(tptoinpcb(tp));
11615 }
11616 }
11617
11618 /*
11619 * Return how much data can be sent without violating the
11620 * cwnd or rwnd.
11621 */
11622
11623 static inline uint32_t
11624 bbr_what_can_we_send(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t sendwin,
11625 uint32_t avail, int32_t sb_offset, uint32_t cts)
11626 {
11627 uint32_t len;
11628
11629 if (ctf_outstanding(tp) >= tp->snd_wnd) {
11630 /* We never want to go over our peers rcv-window */
11631 len = 0;
11632 } else {
11633 uint32_t flight;
11634
11635 flight = ctf_flight_size(tp, (bbr->r_ctl.rc_sacked + bbr->r_ctl.rc_lost_bytes));
11636 if (flight >= sendwin) {
11637 /*
11638 * We have in flight what we are allowed by cwnd (if
11639 * it was rwnd blocking it would have hit above out
11640 * >= tp->snd_wnd).
11641 */
11642 return (0);
11643 }
11644 len = sendwin - flight;
11645 if ((len + ctf_outstanding(tp)) > tp->snd_wnd) {
11646 /* We would send too much (beyond the rwnd) */
11647 len = tp->snd_wnd - ctf_outstanding(tp);
11648 }
11649 if ((len + sb_offset) > avail) {
11650 /*
11651 * We don't have that much in the SB, how much is
11652 * there?
11653 */
11654 len = avail - sb_offset;
11655 }
11656 }
11657 return (len);
11658 }
11659
11660 static inline void
11661 bbr_do_error_accounting(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, int32_t len, int32_t error)
11662 {
11663 #ifdef NETFLIX_STATS
11664 KMOD_TCPSTAT_INC(tcps_sndpack_error);
11665 KMOD_TCPSTAT_ADD(tcps_sndbyte_error, len);
11666 #endif
11667 }
11668
11669 static inline void
11670 bbr_do_send_accounting(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, int32_t len, int32_t error)
11671 {
11672 if (error) {
11673 bbr_do_error_accounting(tp, bbr, rsm, len, error);
11674 return;
11675 }
11676 if (rsm) {
11677 if (rsm->r_flags & BBR_TLP) {
11678 /*
11679 * TLP should not count in retran count, but in its
11680 * own bin
11681 */
11682 #ifdef NETFLIX_STATS
11683 KMOD_TCPSTAT_INC(tcps_tlpresends);
11684 KMOD_TCPSTAT_ADD(tcps_tlpresend_bytes, len);
11685 #endif
11686 } else {
11687 /* Retransmit */
11688 tp->t_sndrexmitpack++;
11689 KMOD_TCPSTAT_INC(tcps_sndrexmitpack);
11690 KMOD_TCPSTAT_ADD(tcps_sndrexmitbyte, len);
11691 #ifdef STATS
11692 stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RETXPB,
11693 len);
11694 #endif
11695 }
11696 /*
11697 * Logs in 0 - 8, 8 is all non probe_bw states 0-7 is
11698 * sub-state
11699 */
11700 counter_u64_add(bbr_state_lost[rsm->r_bbr_state], len);
11701 if (bbr->rc_bbr_state != BBR_STATE_PROBE_BW) {
11702 /* Non probe_bw log in 1, 2, or 4. */
11703 counter_u64_add(bbr_state_resend[bbr->rc_bbr_state], len);
11704 } else {
11705 /*
11706 * Log our probe state 3, and log also 5-13 to show
11707 * us the recovery sub-state for the send. This
11708 * means that 3 == (5+6+7+8+9+10+11+12+13)
11709 */
11710 counter_u64_add(bbr_state_resend[BBR_STATE_PROBE_BW], len);
11711 counter_u64_add(bbr_state_resend[(bbr_state_val(bbr) + 5)], len);
11712 }
11713 /* Place in both 16's the totals of retransmitted */
11714 counter_u64_add(bbr_state_lost[16], len);
11715 counter_u64_add(bbr_state_resend[16], len);
11716 /* Place in 17's the total sent */
11717 counter_u64_add(bbr_state_resend[17], len);
11718 counter_u64_add(bbr_state_lost[17], len);
11719
11720 } else {
11721 /* New sends */
11722 KMOD_TCPSTAT_INC(tcps_sndpack);
11723 KMOD_TCPSTAT_ADD(tcps_sndbyte, len);
11724 /* Place in 17's the total sent */
11725 counter_u64_add(bbr_state_resend[17], len);
11726 counter_u64_add(bbr_state_lost[17], len);
11727 #ifdef STATS
11728 stats_voi_update_abs_u64(tp->t_stats, VOI_TCP_TXPB,
11729 len);
11730 #endif
11731 }
11732 }
11733
11734 static void
11735 bbr_cwnd_limiting(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t in_level)
11736 {
11737 if (bbr->rc_filled_pipe && bbr_target_cwnd_mult_limit && (bbr->rc_use_google == 0)) {
11738 /*
11739 * Limit the cwnd to not be above N x the target plus whats
11740 * is outstanding. The target is based on the current b/w
11741 * estimate.
11742 */
11743 uint32_t target;
11744
11745 target = bbr_get_target_cwnd(bbr, bbr_get_bw(bbr), BBR_UNIT);
11746 target += ctf_outstanding(tp);
11747 target *= bbr_target_cwnd_mult_limit;
11748 if (tp->snd_cwnd > target)
11749 tp->snd_cwnd = target;
11750 bbr_log_type_cwndupd(bbr, 0, 0, 0, 10, 0, 0, __LINE__);
11751 }
11752 }
11753
11754 static int
11755 bbr_window_update_needed(struct tcpcb *tp, struct socket *so, uint32_t recwin, int32_t maxseg)
11756 {
11757 /*
11758 * "adv" is the amount we could increase the window, taking into
11759 * account that we are limited by TCP_MAXWIN << tp->rcv_scale.
11760 */
11761 int32_t adv;
11762 int32_t oldwin;
11763
11764 adv = recwin;
11765 if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt)) {
11766 oldwin = (tp->rcv_adv - tp->rcv_nxt);
11767 if (adv > oldwin)
11768 adv -= oldwin;
11769 else {
11770 /* We can't increase the window */
11771 adv = 0;
11772 }
11773 } else
11774 oldwin = 0;
11775
11776 /*
11777 * If the new window size ends up being the same as or less
11778 * than the old size when it is scaled, then don't force
11779 * a window update.
11780 */
11781 if (oldwin >> tp->rcv_scale >= (adv + oldwin) >> tp->rcv_scale)
11782 return (0);
11783
11784 if (adv >= (2 * maxseg) &&
11785 (adv >= (so->so_rcv.sb_hiwat / 4) ||
11786 recwin <= (so->so_rcv.sb_hiwat / 8) ||
11787 so->so_rcv.sb_hiwat <= 8 * maxseg)) {
11788 return (1);
11789 }
11790 if (2 * adv >= (int32_t) so->so_rcv.sb_hiwat)
11791 return (1);
11792 return (0);
11793 }
11794
11795 /*
11796 * Return 0 on success and a errno on failure to send.
11797 * Note that a 0 return may not mean we sent anything
11798 * if the TCB was on the hpts. A non-zero return
11799 * does indicate the error we got from ip[6]_output.
11800 */
11801 static int
11802 bbr_output_wtime(struct tcpcb *tp, const struct timeval *tv)
11803 {
11804 struct socket *so;
11805 int32_t len;
11806 uint32_t cts;
11807 uint32_t recwin, sendwin;
11808 int32_t sb_offset;
11809 int32_t flags, abandon, error = 0;
11810 struct tcp_log_buffer *lgb = NULL;
11811 struct mbuf *m;
11812 struct mbuf *mb;
11813 uint32_t if_hw_tsomaxsegcount = 0;
11814 uint32_t if_hw_tsomaxsegsize = 0;
11815 uint32_t if_hw_tsomax = 0;
11816 struct ip *ip = NULL;
11817 struct tcp_bbr *bbr;
11818 struct tcphdr *th;
11819 struct udphdr *udp = NULL;
11820 u_char opt[TCP_MAXOLEN];
11821 unsigned ipoptlen, optlen, hdrlen;
11822 unsigned ulen;
11823 uint32_t bbr_seq;
11824 uint32_t delay_calc=0;
11825 uint8_t doing_tlp = 0;
11826 uint8_t local_options;
11827 #ifdef BBR_INVARIANTS
11828 uint8_t doing_retran_from = 0;
11829 uint8_t picked_up_retran = 0;
11830 #endif
11831 uint8_t wanted_cookie = 0;
11832 uint8_t more_to_rxt=0;
11833 int32_t prefetch_so_done = 0;
11834 int32_t prefetch_rsm = 0;
11835 uint32_t tot_len = 0;
11836 uint32_t maxseg, pace_max_segs, p_maxseg;
11837 int32_t csum_flags = 0;
11838 int32_t hw_tls;
11839 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
11840 unsigned ipsec_optlen = 0;
11841
11842 #endif
11843 volatile int32_t sack_rxmit;
11844 struct bbr_sendmap *rsm = NULL;
11845 int32_t tso, mtu;
11846 struct tcpopt to;
11847 int32_t slot = 0;
11848 struct inpcb *inp;
11849 struct sockbuf *sb;
11850 uint32_t hpts_calling;
11851 #ifdef INET6
11852 struct ip6_hdr *ip6 = NULL;
11853 int32_t isipv6;
11854 #endif
11855 uint8_t app_limited = BBR_JR_SENT_DATA;
11856 uint8_t filled_all = 0;
11857 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
11858 /* We take a cache hit here */
11859 memcpy(&bbr->rc_tv, tv, sizeof(struct timeval));
11860 cts = tcp_tv_to_usectick(&bbr->rc_tv);
11861 inp = bbr->rc_inp;
11862 so = inp->inp_socket;
11863 sb = &so->so_snd;
11864 if (sb->sb_flags & SB_TLS_IFNET)
11865 hw_tls = 1;
11866 else
11867 hw_tls = 0;
11868 kern_prefetch(sb, &maxseg);
11869 maxseg = tp->t_maxseg - bbr->rc_last_options;
11870 if (bbr_minseg(bbr) < maxseg) {
11871 tcp_bbr_tso_size_check(bbr, cts);
11872 }
11873 /* Remove any flags that indicate we are pacing on the inp */
11874 pace_max_segs = bbr->r_ctl.rc_pace_max_segs;
11875 p_maxseg = min(maxseg, pace_max_segs);
11876 INP_WLOCK_ASSERT(inp);
11877 #ifdef TCP_OFFLOAD
11878 if (tp->t_flags & TF_TOE)
11879 return (tcp_offload_output(tp));
11880 #endif
11881
11882 #ifdef INET6
11883 if (bbr->r_state) {
11884 /* Use the cache line loaded if possible */
11885 isipv6 = bbr->r_is_v6;
11886 } else {
11887 isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
11888 }
11889 #endif
11890 if (((bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) == 0) &&
11891 tcp_in_hpts(inp)) {
11892 /*
11893 * We are on the hpts for some timer but not hptsi output.
11894 * Possibly remove from the hpts so we can send/recv etc.
11895 */
11896 if ((tp->t_flags & TF_ACKNOW) == 0) {
11897 /*
11898 * No immediate demand right now to send an ack, but
11899 * the user may have read, making room for new data
11900 * (a window update). If so we may want to cancel
11901 * whatever timer is running (KEEP/DEL-ACK?) and
11902 * continue to send out a window update. Or we may
11903 * have gotten more data into the socket buffer to
11904 * send.
11905 */
11906 recwin = lmin(lmax(sbspace(&so->so_rcv), 0),
11907 (long)TCP_MAXWIN << tp->rcv_scale);
11908 if ((bbr_window_update_needed(tp, so, recwin, maxseg) == 0) &&
11909 ((tcp_outflags[tp->t_state] & TH_RST) == 0) &&
11910 ((sbavail(sb) + ((tcp_outflags[tp->t_state] & TH_FIN) ? 1 : 0)) <=
11911 (tp->snd_max - tp->snd_una))) {
11912 /*
11913 * Nothing new to send and no window update
11914 * is needed to send. Lets just return and
11915 * let the timer-run off.
11916 */
11917 return (0);
11918 }
11919 }
11920 tcp_hpts_remove(inp);
11921 bbr_timer_cancel(bbr, __LINE__, cts);
11922 }
11923 if (bbr->r_ctl.rc_last_delay_val) {
11924 /* Calculate a rough delay for early escape to sending */
11925 if (SEQ_GT(cts, bbr->rc_pacer_started))
11926 delay_calc = cts - bbr->rc_pacer_started;
11927 if (delay_calc >= bbr->r_ctl.rc_last_delay_val)
11928 delay_calc -= bbr->r_ctl.rc_last_delay_val;
11929 else
11930 delay_calc = 0;
11931 }
11932 /* Mark that we have called bbr_output(). */
11933 if ((bbr->r_timer_override) ||
11934 (tp->t_state < TCPS_ESTABLISHED)) {
11935 /* Timeouts or early states are exempt */
11936 if (tcp_in_hpts(inp))
11937 tcp_hpts_remove(inp);
11938 } else if (tcp_in_hpts(inp)) {
11939 if ((bbr->r_ctl.rc_last_delay_val) &&
11940 (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT) &&
11941 delay_calc) {
11942 /*
11943 * We were being paced for output and the delay has
11944 * already exceeded when we were supposed to be
11945 * called, lets go ahead and pull out of the hpts
11946 * and call output.
11947 */
11948 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_LATE], 1);
11949 bbr->r_ctl.rc_last_delay_val = 0;
11950 tcp_hpts_remove(inp);
11951 } else if (tp->t_state == TCPS_CLOSED) {
11952 bbr->r_ctl.rc_last_delay_val = 0;
11953 tcp_hpts_remove(inp);
11954 } else {
11955 /*
11956 * On the hpts, you shall not pass! even if ACKNOW
11957 * is on, we will when the hpts fires, unless of
11958 * course we are overdue.
11959 */
11960 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_INPACE], 1);
11961 return (0);
11962 }
11963 }
11964 bbr->rc_cwnd_limited = 0;
11965 if (bbr->r_ctl.rc_last_delay_val) {
11966 /* recalculate the real delay and deal with over/under */
11967 if (SEQ_GT(cts, bbr->rc_pacer_started))
11968 delay_calc = cts - bbr->rc_pacer_started;
11969 else
11970 delay_calc = 0;
11971 if (delay_calc >= bbr->r_ctl.rc_last_delay_val)
11972 /* Setup the delay which will be added in */
11973 delay_calc -= bbr->r_ctl.rc_last_delay_val;
11974 else {
11975 /*
11976 * We are early setup to adjust
11977 * our slot time.
11978 */
11979 uint64_t merged_val;
11980
11981 bbr->r_ctl.rc_agg_early += (bbr->r_ctl.rc_last_delay_val - delay_calc);
11982 bbr->r_agg_early_set = 1;
11983 if (bbr->r_ctl.rc_hptsi_agg_delay) {
11984 if (bbr->r_ctl.rc_hptsi_agg_delay >= bbr->r_ctl.rc_agg_early) {
11985 /* Nope our previous late cancels out the early */
11986 bbr->r_ctl.rc_hptsi_agg_delay -= bbr->r_ctl.rc_agg_early;
11987 bbr->r_agg_early_set = 0;
11988 bbr->r_ctl.rc_agg_early = 0;
11989 } else {
11990 bbr->r_ctl.rc_agg_early -= bbr->r_ctl.rc_hptsi_agg_delay;
11991 bbr->r_ctl.rc_hptsi_agg_delay = 0;
11992 }
11993 }
11994 merged_val = bbr->rc_pacer_started;
11995 merged_val <<= 32;
11996 merged_val |= bbr->r_ctl.rc_last_delay_val;
11997 bbr_log_pacing_delay_calc(bbr, inp->inp_hpts_calls,
11998 bbr->r_ctl.rc_agg_early, cts, delay_calc, merged_val,
11999 bbr->r_agg_early_set, 3);
12000 bbr->r_ctl.rc_last_delay_val = 0;
12001 BBR_STAT_INC(bbr_early);
12002 delay_calc = 0;
12003 }
12004 } else {
12005 /* We were not delayed due to hptsi */
12006 if (bbr->r_agg_early_set)
12007 bbr->r_ctl.rc_agg_early = 0;
12008 bbr->r_agg_early_set = 0;
12009 delay_calc = 0;
12010 }
12011 if (delay_calc) {
12012 /*
12013 * We had a hptsi delay which means we are falling behind on
12014 * sending at the expected rate. Calculate an extra amount
12015 * of data we can send, if any, to put us back on track.
12016 */
12017 if ((bbr->r_ctl.rc_hptsi_agg_delay + delay_calc) < bbr->r_ctl.rc_hptsi_agg_delay)
12018 bbr->r_ctl.rc_hptsi_agg_delay = 0xffffffff;
12019 else
12020 bbr->r_ctl.rc_hptsi_agg_delay += delay_calc;
12021 }
12022 sendwin = min(tp->snd_wnd, tp->snd_cwnd);
12023 if ((tp->snd_una == tp->snd_max) &&
12024 (bbr->rc_bbr_state != BBR_STATE_IDLE_EXIT) &&
12025 (sbavail(sb))) {
12026 /*
12027 * Ok we have been idle with nothing outstanding
12028 * we possibly need to start fresh with either a new
12029 * suite of states or a fast-ramp up.
12030 */
12031 bbr_restart_after_idle(bbr,
12032 cts, bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time));
12033 }
12034 /*
12035 * Now was there a hptsi delay where we are behind? We only count
12036 * being behind if: a) We are not in recovery. b) There was a delay.
12037 * <and> c) We had room to send something.
12038 *
12039 */
12040 hpts_calling = inp->inp_hpts_calls;
12041 inp->inp_hpts_calls = 0;
12042 if (bbr->r_ctl.rc_hpts_flags & PACE_TMR_MASK) {
12043 int retval;
12044
12045 retval = bbr_process_timers(tp, bbr, cts, hpts_calling);
12046 if (retval != 0) {
12047 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_ATIMER], 1);
12048 /*
12049 * If timers want tcp_drop(), then pass error out,
12050 * otherwise suppress it.
12051 */
12052 return (retval < 0 ? retval : 0);
12053 }
12054 }
12055 bbr->rc_inp->inp_flags2 &= ~INP_MBUF_QUEUE_READY;
12056 if (hpts_calling &&
12057 (bbr->r_ctl.rc_hpts_flags & PACE_PKT_OUTPUT)) {
12058 bbr->r_ctl.rc_last_delay_val = 0;
12059 }
12060 bbr->r_timer_override = 0;
12061 bbr->r_wanted_output = 0;
12062 /*
12063 * For TFO connections in SYN_RECEIVED, only allow the initial
12064 * SYN|ACK and those sent by the retransmit timer.
12065 */
12066 if (IS_FASTOPEN(tp->t_flags) &&
12067 ((tp->t_state == TCPS_SYN_RECEIVED) ||
12068 (tp->t_state == TCPS_SYN_SENT)) &&
12069 SEQ_GT(tp->snd_max, tp->snd_una) && /* initial SYN or SYN|ACK sent */
12070 (tp->t_rxtshift == 0)) { /* not a retransmit */
12071 len = 0;
12072 goto just_return_nolock;
12073 }
12074 /*
12075 * Before sending anything check for a state update. For hpts
12076 * calling without input this is important. If its input calling
12077 * then this was already done.
12078 */
12079 if (bbr->rc_use_google == 0)
12080 bbr_check_bbr_for_state(bbr, cts, __LINE__, 0);
12081 again:
12082 /*
12083 * If we've recently taken a timeout, snd_max will be greater than
12084 * snd_max. BBR in general does not pay much attention to snd_nxt
12085 * for historic reasons the persist timer still uses it. This means
12086 * we have to look at it. All retransmissions that are not persits
12087 * use the rsm that needs to be sent so snd_nxt is ignored. At the
12088 * end of this routine we pull snd_nxt always up to snd_max.
12089 */
12090 doing_tlp = 0;
12091 #ifdef BBR_INVARIANTS
12092 doing_retran_from = picked_up_retran = 0;
12093 #endif
12094 error = 0;
12095 tso = 0;
12096 slot = 0;
12097 mtu = 0;
12098 sendwin = min(tp->snd_wnd, tp->snd_cwnd);
12099 sb_offset = tp->snd_max - tp->snd_una;
12100 flags = tcp_outflags[tp->t_state];
12101 sack_rxmit = 0;
12102 len = 0;
12103 rsm = NULL;
12104 if (flags & TH_RST) {
12105 SOCKBUF_LOCK(sb);
12106 goto send;
12107 }
12108 recheck_resend:
12109 while (bbr->r_ctl.rc_free_cnt < bbr_min_req_free) {
12110 /* We need to always have one in reserve */
12111 rsm = bbr_alloc(bbr);
12112 if (rsm == NULL) {
12113 error = ENOMEM;
12114 /* Lie to get on the hpts */
12115 tot_len = tp->t_maxseg;
12116 if (hpts_calling)
12117 /* Retry in a ms */
12118 slot = 1001;
12119 goto just_return_nolock;
12120 }
12121 TAILQ_INSERT_TAIL(&bbr->r_ctl.rc_free, rsm, r_next);
12122 bbr->r_ctl.rc_free_cnt++;
12123 rsm = NULL;
12124 }
12125 /* What do we send, a resend? */
12126 if (bbr->r_ctl.rc_resend == NULL) {
12127 /* Check for rack timeout */
12128 bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts);
12129 if (bbr->r_ctl.rc_resend) {
12130 #ifdef BBR_INVARIANTS
12131 picked_up_retran = 1;
12132 #endif
12133 bbr_cong_signal(tp, NULL, CC_NDUPACK, bbr->r_ctl.rc_resend);
12134 }
12135 }
12136 if (bbr->r_ctl.rc_resend) {
12137 rsm = bbr->r_ctl.rc_resend;
12138 #ifdef BBR_INVARIANTS
12139 doing_retran_from = 1;
12140 #endif
12141 /* Remove any TLP flags its a RACK or T-O */
12142 rsm->r_flags &= ~BBR_TLP;
12143 bbr->r_ctl.rc_resend = NULL;
12144 if (SEQ_LT(rsm->r_start, tp->snd_una)) {
12145 #ifdef BBR_INVARIANTS
12146 panic("Huh, tp:%p bbr:%p rsm:%p start:%u < snd_una:%u\n",
12147 tp, bbr, rsm, rsm->r_start, tp->snd_una);
12148 goto recheck_resend;
12149 #else
12150 /* TSNH */
12151 rsm = NULL;
12152 goto recheck_resend;
12153 #endif
12154 }
12155 if (rsm->r_flags & BBR_HAS_SYN) {
12156 /* Only retransmit a SYN by itself */
12157 len = 0;
12158 if ((flags & TH_SYN) == 0) {
12159 /* Huh something is wrong */
12160 rsm->r_start++;
12161 if (rsm->r_start == rsm->r_end) {
12162 /* Clean it up, somehow we missed the ack? */
12163 bbr_log_syn(tp, NULL);
12164 } else {
12165 /* TFO with data? */
12166 rsm->r_flags &= ~BBR_HAS_SYN;
12167 len = rsm->r_end - rsm->r_start;
12168 }
12169 } else {
12170 /* Retransmitting SYN */
12171 rsm = NULL;
12172 SOCKBUF_LOCK(sb);
12173 goto send;
12174 }
12175 } else
12176 len = rsm->r_end - rsm->r_start;
12177 if ((bbr->rc_resends_use_tso == 0) &&
12178 (len > maxseg)) {
12179 len = maxseg;
12180 more_to_rxt = 1;
12181 }
12182 sb_offset = rsm->r_start - tp->snd_una;
12183 if (len > 0) {
12184 sack_rxmit = 1;
12185 KMOD_TCPSTAT_INC(tcps_sack_rexmits);
12186 KMOD_TCPSTAT_ADD(tcps_sack_rexmit_bytes,
12187 min(len, maxseg));
12188 } else {
12189 /* I dont think this can happen */
12190 rsm = NULL;
12191 goto recheck_resend;
12192 }
12193 BBR_STAT_INC(bbr_resends_set);
12194 } else if (bbr->r_ctl.rc_tlp_send) {
12195 /*
12196 * Tail loss probe
12197 */
12198 doing_tlp = 1;
12199 rsm = bbr->r_ctl.rc_tlp_send;
12200 bbr->r_ctl.rc_tlp_send = NULL;
12201 sack_rxmit = 1;
12202 len = rsm->r_end - rsm->r_start;
12203 if ((bbr->rc_resends_use_tso == 0) && (len > maxseg))
12204 len = maxseg;
12205
12206 if (SEQ_GT(tp->snd_una, rsm->r_start)) {
12207 #ifdef BBR_INVARIANTS
12208 panic("tp:%p bbc:%p snd_una:%u rsm:%p r_start:%u",
12209 tp, bbr, tp->snd_una, rsm, rsm->r_start);
12210 #else
12211 /* TSNH */
12212 rsm = NULL;
12213 goto recheck_resend;
12214 #endif
12215 }
12216 sb_offset = rsm->r_start - tp->snd_una;
12217 BBR_STAT_INC(bbr_tlp_set);
12218 }
12219 /*
12220 * Enforce a connection sendmap count limit if set
12221 * as long as we are not retransmiting.
12222 */
12223 if ((rsm == NULL) &&
12224 (V_tcp_map_entries_limit > 0) &&
12225 (bbr->r_ctl.rc_num_maps_alloced >= V_tcp_map_entries_limit)) {
12226 BBR_STAT_INC(bbr_alloc_limited);
12227 if (!bbr->alloc_limit_reported) {
12228 bbr->alloc_limit_reported = 1;
12229 BBR_STAT_INC(bbr_alloc_limited_conns);
12230 }
12231 goto just_return_nolock;
12232 }
12233 #ifdef BBR_INVARIANTS
12234 if (rsm && SEQ_LT(rsm->r_start, tp->snd_una)) {
12235 panic("tp:%p bbr:%p rsm:%p sb_offset:%u len:%u",
12236 tp, bbr, rsm, sb_offset, len);
12237 }
12238 #endif
12239 /*
12240 * Get standard flags, and add SYN or FIN if requested by 'hidden'
12241 * state flags.
12242 */
12243 if (tp->t_flags & TF_NEEDFIN && (rsm == NULL))
12244 flags |= TH_FIN;
12245 if (tp->t_flags & TF_NEEDSYN)
12246 flags |= TH_SYN;
12247
12248 if (rsm && (rsm->r_flags & BBR_HAS_FIN)) {
12249 /* we are retransmitting the fin */
12250 len--;
12251 if (len) {
12252 /*
12253 * When retransmitting data do *not* include the
12254 * FIN. This could happen from a TLP probe if we
12255 * allowed data with a FIN.
12256 */
12257 flags &= ~TH_FIN;
12258 }
12259 } else if (rsm) {
12260 if (flags & TH_FIN)
12261 flags &= ~TH_FIN;
12262 }
12263 if ((sack_rxmit == 0) && (prefetch_rsm == 0)) {
12264 void *end_rsm;
12265
12266 end_rsm = TAILQ_LAST_FAST(&bbr->r_ctl.rc_tmap, bbr_sendmap, r_tnext);
12267 if (end_rsm)
12268 kern_prefetch(end_rsm, &prefetch_rsm);
12269 prefetch_rsm = 1;
12270 }
12271 SOCKBUF_LOCK(sb);
12272 /*
12273 * If snd_nxt == snd_max and we have transmitted a FIN, the
12274 * sb_offset will be > 0 even if so_snd.sb_cc is 0, resulting in a
12275 * negative length. This can also occur when TCP opens up its
12276 * congestion window while receiving additional duplicate acks after
12277 * fast-retransmit because TCP will reset snd_nxt to snd_max after
12278 * the fast-retransmit.
12279 *
12280 * In the normal retransmit-FIN-only case, however, snd_nxt will be
12281 * set to snd_una, the sb_offset will be 0, and the length may wind
12282 * up 0.
12283 *
12284 * If sack_rxmit is true we are retransmitting from the scoreboard
12285 * in which case len is already set.
12286 */
12287 if (sack_rxmit == 0) {
12288 uint32_t avail;
12289
12290 avail = sbavail(sb);
12291 if (SEQ_GT(tp->snd_max, tp->snd_una))
12292 sb_offset = tp->snd_max - tp->snd_una;
12293 else
12294 sb_offset = 0;
12295 if (bbr->rc_tlp_new_data) {
12296 /* TLP is forcing out new data */
12297 uint32_t tlplen;
12298
12299 doing_tlp = 1;
12300 tlplen = maxseg;
12301
12302 if (tlplen > (uint32_t)(avail - sb_offset)) {
12303 tlplen = (uint32_t)(avail - sb_offset);
12304 }
12305 if (tlplen > tp->snd_wnd) {
12306 len = tp->snd_wnd;
12307 } else {
12308 len = tlplen;
12309 }
12310 bbr->rc_tlp_new_data = 0;
12311 } else {
12312 len = bbr_what_can_we_send(tp, bbr, sendwin, avail, sb_offset, cts);
12313 if ((len < p_maxseg) &&
12314 (bbr->rc_in_persist == 0) &&
12315 (ctf_outstanding(tp) >= (2 * p_maxseg)) &&
12316 ((avail - sb_offset) >= p_maxseg)) {
12317 /*
12318 * We are not completing whats in the socket
12319 * buffer (i.e. there is at least a segment
12320 * waiting to send) and we have 2 or more
12321 * segments outstanding. There is no sense
12322 * of sending a little piece. Lets defer and
12323 * and wait until we can send a whole
12324 * segment.
12325 */
12326 len = 0;
12327 }
12328 if (bbr->rc_in_persist) {
12329 /*
12330 * We are in persists, figure out if
12331 * a retransmit is available (maybe the previous
12332 * persists we sent) or if we have to send new
12333 * data.
12334 */
12335 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map);
12336 if (rsm) {
12337 len = rsm->r_end - rsm->r_start;
12338 if (rsm->r_flags & BBR_HAS_FIN)
12339 len--;
12340 if ((bbr->rc_resends_use_tso == 0) && (len > maxseg))
12341 len = maxseg;
12342 if (len > 1)
12343 BBR_STAT_INC(bbr_persist_reneg);
12344 /*
12345 * XXXrrs we could force the len to
12346 * 1 byte here to cause the chunk to
12347 * split apart.. but that would then
12348 * mean we always retransmit it as
12349 * one byte even after the window
12350 * opens.
12351 */
12352 sack_rxmit = 1;
12353 sb_offset = rsm->r_start - tp->snd_una;
12354 } else {
12355 /*
12356 * First time through in persists or peer
12357 * acked our one byte. Though we do have
12358 * to have something in the sb.
12359 */
12360 len = 1;
12361 sb_offset = 0;
12362 if (avail == 0)
12363 len = 0;
12364 }
12365 }
12366 }
12367 }
12368 if (prefetch_so_done == 0) {
12369 kern_prefetch(so, &prefetch_so_done);
12370 prefetch_so_done = 1;
12371 }
12372 /*
12373 * Lop off SYN bit if it has already been sent. However, if this is
12374 * SYN-SENT state and if segment contains data and if we don't know
12375 * that foreign host supports TAO, suppress sending segment.
12376 */
12377 if ((flags & TH_SYN) && (rsm == NULL) &&
12378 SEQ_GT(tp->snd_max, tp->snd_una)) {
12379 if (tp->t_state != TCPS_SYN_RECEIVED)
12380 flags &= ~TH_SYN;
12381 /*
12382 * When sending additional segments following a TFO SYN|ACK,
12383 * do not include the SYN bit.
12384 */
12385 if (IS_FASTOPEN(tp->t_flags) &&
12386 (tp->t_state == TCPS_SYN_RECEIVED))
12387 flags &= ~TH_SYN;
12388 sb_offset--, len++;
12389 if (sbavail(sb) == 0)
12390 len = 0;
12391 } else if ((flags & TH_SYN) && rsm) {
12392 /*
12393 * Subtract one from the len for the SYN being
12394 * retransmitted.
12395 */
12396 len--;
12397 }
12398 /*
12399 * Be careful not to send data and/or FIN on SYN segments. This
12400 * measure is needed to prevent interoperability problems with not
12401 * fully conformant TCP implementations.
12402 */
12403 if ((flags & TH_SYN) && (tp->t_flags & TF_NOOPT)) {
12404 len = 0;
12405 flags &= ~TH_FIN;
12406 }
12407 /*
12408 * On TFO sockets, ensure no data is sent in the following cases:
12409 *
12410 * - When retransmitting SYN|ACK on a passively-created socket
12411 * - When retransmitting SYN on an actively created socket
12412 * - When sending a zero-length cookie (cookie request) on an
12413 * actively created socket
12414 * - When the socket is in the CLOSED state (RST is being sent)
12415 */
12416 if (IS_FASTOPEN(tp->t_flags) &&
12417 (((flags & TH_SYN) && (tp->t_rxtshift > 0)) ||
12418 ((tp->t_state == TCPS_SYN_SENT) &&
12419 (tp->t_tfo_client_cookie_len == 0)) ||
12420 (flags & TH_RST))) {
12421 len = 0;
12422 sack_rxmit = 0;
12423 rsm = NULL;
12424 }
12425 /* Without fast-open there should never be data sent on a SYN */
12426 if ((flags & TH_SYN) && (!IS_FASTOPEN(tp->t_flags)))
12427 len = 0;
12428 if (len <= 0) {
12429 /*
12430 * If FIN has been sent but not acked, but we haven't been
12431 * called to retransmit, len will be < 0. Otherwise, window
12432 * shrank after we sent into it. If window shrank to 0,
12433 * cancel pending retransmit, pull snd_nxt back to (closed)
12434 * window, and set the persist timer if it isn't already
12435 * going. If the window didn't close completely, just wait
12436 * for an ACK.
12437 *
12438 * We also do a general check here to ensure that we will
12439 * set the persist timer when we have data to send, but a
12440 * 0-byte window. This makes sure the persist timer is set
12441 * even if the packet hits one of the "goto send" lines
12442 * below.
12443 */
12444 len = 0;
12445 if ((tp->snd_wnd == 0) &&
12446 (TCPS_HAVEESTABLISHED(tp->t_state)) &&
12447 (tp->snd_una == tp->snd_max) &&
12448 (sb_offset < (int)sbavail(sb))) {
12449 /*
12450 * Not enough room in the rwnd to send
12451 * a paced segment out.
12452 */
12453 bbr_enter_persist(tp, bbr, cts, __LINE__);
12454 }
12455 } else if ((rsm == NULL) &&
12456 (doing_tlp == 0) &&
12457 (len < bbr->r_ctl.rc_pace_max_segs)) {
12458 /*
12459 * We are not sending a full segment for
12460 * some reason. Should we not send anything (think
12461 * sws or persists)?
12462 */
12463 if ((tp->snd_wnd < min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) &&
12464 (TCPS_HAVEESTABLISHED(tp->t_state)) &&
12465 (len < (int)(sbavail(sb) - sb_offset))) {
12466 /*
12467 * Here the rwnd is less than
12468 * the pacing size, this is not a retransmit,
12469 * we are established and
12470 * the send is not the last in the socket buffer
12471 * lets not send, and possibly enter persists.
12472 */
12473 len = 0;
12474 if (tp->snd_max == tp->snd_una)
12475 bbr_enter_persist(tp, bbr, cts, __LINE__);
12476 } else if ((tp->snd_cwnd >= bbr->r_ctl.rc_pace_max_segs) &&
12477 (ctf_flight_size(tp, (bbr->r_ctl.rc_sacked +
12478 bbr->r_ctl.rc_lost_bytes)) > (2 * maxseg)) &&
12479 (len < (int)(sbavail(sb) - sb_offset)) &&
12480 (len < bbr_minseg(bbr))) {
12481 /*
12482 * Here we are not retransmitting, and
12483 * the cwnd is not so small that we could
12484 * not send at least a min size (rxt timer
12485 * not having gone off), We have 2 segments or
12486 * more already in flight, its not the tail end
12487 * of the socket buffer and the cwnd is blocking
12488 * us from sending out minimum pacing segment size.
12489 * Lets not send anything.
12490 */
12491 bbr->rc_cwnd_limited = 1;
12492 len = 0;
12493 } else if (((tp->snd_wnd - ctf_outstanding(tp)) <
12494 min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) &&
12495 (ctf_flight_size(tp, (bbr->r_ctl.rc_sacked +
12496 bbr->r_ctl.rc_lost_bytes)) > (2 * maxseg)) &&
12497 (len < (int)(sbavail(sb) - sb_offset)) &&
12498 (TCPS_HAVEESTABLISHED(tp->t_state))) {
12499 /*
12500 * Here we have a send window but we have
12501 * filled it up and we can't send another pacing segment.
12502 * We also have in flight more than 2 segments
12503 * and we are not completing the sb i.e. we allow
12504 * the last bytes of the sb to go out even if
12505 * its not a full pacing segment.
12506 */
12507 len = 0;
12508 }
12509 }
12510 /* len will be >= 0 after this point. */
12511 KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__));
12512 tcp_sndbuf_autoscale(tp, so, sendwin);
12513 /*
12514 *
12515 */
12516 if (bbr->rc_in_persist &&
12517 len &&
12518 (rsm == NULL) &&
12519 (len < min((bbr->r_ctl.rc_high_rwnd/2), bbr->r_ctl.rc_pace_max_segs))) {
12520 /*
12521 * We are in persist, not doing a retransmit and don't have enough space
12522 * yet to send a full TSO. So is it at the end of the sb
12523 * if so we need to send else nuke to 0 and don't send.
12524 */
12525 int sbleft;
12526 if (sbavail(sb) > sb_offset)
12527 sbleft = sbavail(sb) - sb_offset;
12528 else
12529 sbleft = 0;
12530 if (sbleft >= min((bbr->r_ctl.rc_high_rwnd/2), bbr->r_ctl.rc_pace_max_segs)) {
12531 /* not at end of sb lets not send */
12532 len = 0;
12533 }
12534 }
12535 /*
12536 * Decide if we can use TCP Segmentation Offloading (if supported by
12537 * hardware).
12538 *
12539 * TSO may only be used if we are in a pure bulk sending state. The
12540 * presence of TCP-MD5, SACK retransmits, SACK advertizements and IP
12541 * options prevent using TSO. With TSO the TCP header is the same
12542 * (except for the sequence number) for all generated packets. This
12543 * makes it impossible to transmit any options which vary per
12544 * generated segment or packet.
12545 *
12546 * IPv4 handling has a clear separation of ip options and ip header
12547 * flags while IPv6 combines both in in6p_outputopts. ip6_optlen()
12548 * does the right thing below to provide length of just ip options
12549 * and thus checking for ipoptlen is enough to decide if ip options
12550 * are present.
12551 */
12552 #ifdef INET6
12553 if (isipv6)
12554 ipoptlen = ip6_optlen(inp);
12555 else
12556 #endif
12557 if (inp->inp_options)
12558 ipoptlen = inp->inp_options->m_len -
12559 offsetof(struct ipoption, ipopt_list);
12560 else
12561 ipoptlen = 0;
12562 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
12563 /*
12564 * Pre-calculate here as we save another lookup into the darknesses
12565 * of IPsec that way and can actually decide if TSO is ok.
12566 */
12567 #ifdef INET6
12568 if (isipv6 && IPSEC_ENABLED(ipv6))
12569 ipsec_optlen = IPSEC_HDRSIZE(ipv6, inp);
12570 #ifdef INET
12571 else
12572 #endif
12573 #endif /* INET6 */
12574 #ifdef INET
12575 if (IPSEC_ENABLED(ipv4))
12576 ipsec_optlen = IPSEC_HDRSIZE(ipv4, inp);
12577 #endif /* INET */
12578 #endif /* IPSEC */
12579 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
12580 ipoptlen += ipsec_optlen;
12581 #endif
12582 if ((tp->t_flags & TF_TSO) && V_tcp_do_tso &&
12583 (len > maxseg) &&
12584 (tp->t_port == 0) &&
12585 ((tp->t_flags & TF_SIGNATURE) == 0) &&
12586 tp->rcv_numsacks == 0 &&
12587 ipoptlen == 0)
12588 tso = 1;
12589
12590 recwin = lmin(lmax(sbspace(&so->so_rcv), 0),
12591 (long)TCP_MAXWIN << tp->rcv_scale);
12592 /*
12593 * Sender silly window avoidance. We transmit under the following
12594 * conditions when len is non-zero:
12595 *
12596 * - We have a full segment (or more with TSO) - This is the last
12597 * buffer in a write()/send() and we are either idle or running
12598 * NODELAY - we've timed out (e.g. persist timer) - we have more
12599 * then 1/2 the maximum send window's worth of data (receiver may be
12600 * limited the window size) - we need to retransmit
12601 */
12602 if (rsm)
12603 goto send;
12604 if (len) {
12605 if (sack_rxmit)
12606 goto send;
12607 if (len >= p_maxseg)
12608 goto send;
12609 /*
12610 * NOTE! on localhost connections an 'ack' from the remote
12611 * end may occur synchronously with the output and cause us
12612 * to flush a buffer queued with moretocome. XXX
12613 *
12614 */
12615 if (((tp->t_flags & TF_MORETOCOME) == 0) && /* normal case */
12616 ((tp->t_flags & TF_NODELAY) ||
12617 ((uint32_t)len + (uint32_t)sb_offset) >= sbavail(&so->so_snd)) &&
12618 (tp->t_flags & TF_NOPUSH) == 0) {
12619 goto send;
12620 }
12621 if ((tp->snd_una == tp->snd_max) && len) { /* Nothing outstanding */
12622 goto send;
12623 }
12624 if (len >= tp->max_sndwnd / 2 && tp->max_sndwnd > 0) {
12625 goto send;
12626 }
12627 }
12628 /*
12629 * Sending of standalone window updates.
12630 *
12631 * Window updates are important when we close our window due to a
12632 * full socket buffer and are opening it again after the application
12633 * reads data from it. Once the window has opened again and the
12634 * remote end starts to send again the ACK clock takes over and
12635 * provides the most current window information.
12636 *
12637 * We must avoid the silly window syndrome whereas every read from
12638 * the receive buffer, no matter how small, causes a window update
12639 * to be sent. We also should avoid sending a flurry of window
12640 * updates when the socket buffer had queued a lot of data and the
12641 * application is doing small reads.
12642 *
12643 * Prevent a flurry of pointless window updates by only sending an
12644 * update when we can increase the advertized window by more than
12645 * 1/4th of the socket buffer capacity. When the buffer is getting
12646 * full or is very small be more aggressive and send an update
12647 * whenever we can increase by two mss sized segments. In all other
12648 * situations the ACK's to new incoming data will carry further
12649 * window increases.
12650 *
12651 * Don't send an independent window update if a delayed ACK is
12652 * pending (it will get piggy-backed on it) or the remote side
12653 * already has done a half-close and won't send more data. Skip
12654 * this if the connection is in T/TCP half-open state.
12655 */
12656 if (recwin > 0 && !(tp->t_flags & TF_NEEDSYN) &&
12657 !(tp->t_flags & TF_DELACK) &&
12658 !TCPS_HAVERCVDFIN(tp->t_state)) {
12659 /* Check to see if we should do a window update */
12660 if (bbr_window_update_needed(tp, so, recwin, maxseg))
12661 goto send;
12662 }
12663 /*
12664 * Send if we owe the peer an ACK, RST, SYN. ACKNOW
12665 * is also a catch-all for the retransmit timer timeout case.
12666 */
12667 if (tp->t_flags & TF_ACKNOW) {
12668 goto send;
12669 }
12670 if (flags & TH_RST) {
12671 /* Always send a RST if one is due */
12672 goto send;
12673 }
12674 if ((flags & TH_SYN) && (tp->t_flags & TF_NEEDSYN) == 0) {
12675 goto send;
12676 }
12677 /*
12678 * If our state indicates that FIN should be sent and we have not
12679 * yet done so, then we need to send.
12680 */
12681 if (flags & TH_FIN &&
12682 ((tp->t_flags & TF_SENTFIN) == 0)) {
12683 goto send;
12684 }
12685 /*
12686 * No reason to send a segment, just return.
12687 */
12688 just_return:
12689 SOCKBUF_UNLOCK(sb);
12690 just_return_nolock:
12691 if (tot_len)
12692 slot = bbr_get_pacing_delay(bbr, bbr->r_ctl.rc_bbr_hptsi_gain, tot_len, cts, 0);
12693 if (bbr->rc_no_pacing)
12694 slot = 0;
12695 if (tot_len == 0) {
12696 if ((ctf_outstanding(tp) + min((bbr->r_ctl.rc_high_rwnd/2), bbr_minseg(bbr))) >=
12697 tp->snd_wnd) {
12698 BBR_STAT_INC(bbr_rwnd_limited);
12699 app_limited = BBR_JR_RWND_LIMITED;
12700 bbr_cwnd_limiting(tp, bbr, ctf_outstanding(tp));
12701 if ((bbr->rc_in_persist == 0) &&
12702 TCPS_HAVEESTABLISHED(tp->t_state) &&
12703 (tp->snd_max == tp->snd_una) &&
12704 sbavail(&so->so_snd)) {
12705 /* No send window.. we must enter persist */
12706 bbr_enter_persist(tp, bbr, bbr->r_ctl.rc_rcvtime, __LINE__);
12707 }
12708 } else if (ctf_outstanding(tp) >= sbavail(sb)) {
12709 BBR_STAT_INC(bbr_app_limited);
12710 app_limited = BBR_JR_APP_LIMITED;
12711 bbr_cwnd_limiting(tp, bbr, ctf_outstanding(tp));
12712 } else if ((ctf_flight_size(tp, (bbr->r_ctl.rc_sacked +
12713 bbr->r_ctl.rc_lost_bytes)) + p_maxseg) >= tp->snd_cwnd) {
12714 BBR_STAT_INC(bbr_cwnd_limited);
12715 app_limited = BBR_JR_CWND_LIMITED;
12716 bbr_cwnd_limiting(tp, bbr, ctf_flight_size(tp, (bbr->r_ctl.rc_sacked +
12717 bbr->r_ctl.rc_lost_bytes)));
12718 bbr->rc_cwnd_limited = 1;
12719 } else {
12720 BBR_STAT_INC(bbr_app_limited);
12721 app_limited = BBR_JR_APP_LIMITED;
12722 bbr_cwnd_limiting(tp, bbr, ctf_outstanding(tp));
12723 }
12724 bbr->r_ctl.rc_hptsi_agg_delay = 0;
12725 bbr->r_agg_early_set = 0;
12726 bbr->r_ctl.rc_agg_early = 0;
12727 bbr->r_ctl.rc_last_delay_val = 0;
12728 } else if (bbr->rc_use_google == 0)
12729 bbr_check_bbr_for_state(bbr, cts, __LINE__, 0);
12730 /* Are we app limited? */
12731 if ((app_limited == BBR_JR_APP_LIMITED) ||
12732 (app_limited == BBR_JR_RWND_LIMITED)) {
12733 /**
12734 * We are application limited.
12735 */
12736 bbr->r_ctl.r_app_limited_until = (ctf_flight_size(tp, (bbr->r_ctl.rc_sacked +
12737 bbr->r_ctl.rc_lost_bytes)) + bbr->r_ctl.rc_delivered);
12738 }
12739 if (tot_len == 0)
12740 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_JUSTRET], 1);
12741 /* Dont update the time if we did not send */
12742 bbr->r_ctl.rc_last_delay_val = 0;
12743 bbr->rc_output_starts_timer = 1;
12744 bbr_start_hpts_timer(bbr, tp, cts, 9, slot, tot_len);
12745 bbr_log_type_just_return(bbr, cts, tot_len, hpts_calling, app_limited, p_maxseg, len);
12746 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) {
12747 /* Make sure snd_nxt is drug up */
12748 tp->snd_nxt = tp->snd_max;
12749 }
12750 return (error);
12751
12752 send:
12753 if (doing_tlp == 0) {
12754 /*
12755 * Data not a TLP, and its not the rxt firing. If it is the
12756 * rxt firing, we want to leave the tlp_in_progress flag on
12757 * so we don't send another TLP. It has to be a rack timer
12758 * or normal send (response to acked data) to clear the tlp
12759 * in progress flag.
12760 */
12761 bbr->rc_tlp_in_progress = 0;
12762 bbr->rc_tlp_rtx_out = 0;
12763 } else {
12764 /*
12765 * Its a TLP.
12766 */
12767 bbr->rc_tlp_in_progress = 1;
12768 }
12769 bbr_timer_cancel(bbr, __LINE__, cts);
12770 if (rsm == NULL) {
12771 if (sbused(sb) > 0) {
12772 /*
12773 * This is sub-optimal. We only send a stand alone
12774 * FIN on its own segment.
12775 */
12776 if (flags & TH_FIN) {
12777 flags &= ~TH_FIN;
12778 if ((len == 0) && ((tp->t_flags & TF_ACKNOW) == 0)) {
12779 /* Lets not send this */
12780 slot = 0;
12781 goto just_return;
12782 }
12783 }
12784 }
12785 } else {
12786 /*
12787 * We do *not* send a FIN on a retransmit if it has data.
12788 * The if clause here where len > 1 should never come true.
12789 */
12790 if ((len > 0) &&
12791 (((rsm->r_flags & BBR_HAS_FIN) == 0) &&
12792 (flags & TH_FIN))) {
12793 flags &= ~TH_FIN;
12794 len--;
12795 }
12796 }
12797 SOCKBUF_LOCK_ASSERT(sb);
12798 if (len > 0) {
12799 if ((tp->snd_una == tp->snd_max) &&
12800 (bbr_calc_time(cts, bbr->r_ctl.rc_went_idle_time) >= bbr_rtt_probe_time)) {
12801 /*
12802 * This qualifies as a RTT_PROBE session since we
12803 * drop the data outstanding to nothing and waited
12804 * more than bbr_rtt_probe_time.
12805 */
12806 bbr_log_rtt_shrinks(bbr, cts, 0, 0, __LINE__, BBR_RTTS_WASIDLE, 0);
12807 bbr_set_reduced_rtt(bbr, cts, __LINE__);
12808 }
12809 if (len >= maxseg)
12810 tp->t_flags2 |= TF2_PLPMTU_MAXSEGSNT;
12811 else
12812 tp->t_flags2 &= ~TF2_PLPMTU_MAXSEGSNT;
12813 }
12814 /*
12815 * Before ESTABLISHED, force sending of initial options unless TCP
12816 * set not to do any options. NOTE: we assume that the IP/TCP header
12817 * plus TCP options always fit in a single mbuf, leaving room for a
12818 * maximum link header, i.e. max_linkhdr + sizeof (struct tcpiphdr)
12819 * + optlen <= MCLBYTES
12820 */
12821 optlen = 0;
12822 #ifdef INET6
12823 if (isipv6)
12824 hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
12825 else
12826 #endif
12827 hdrlen = sizeof(struct tcpiphdr);
12828
12829 /*
12830 * Compute options for segment. We only have to care about SYN and
12831 * established connection segments. Options for SYN-ACK segments
12832 * are handled in TCP syncache.
12833 */
12834 to.to_flags = 0;
12835 local_options = 0;
12836 if ((tp->t_flags & TF_NOOPT) == 0) {
12837 /* Maximum segment size. */
12838 if (flags & TH_SYN) {
12839 to.to_mss = tcp_mssopt(&inp->inp_inc);
12840 if (tp->t_port)
12841 to.to_mss -= V_tcp_udp_tunneling_overhead;
12842 to.to_flags |= TOF_MSS;
12843 /*
12844 * On SYN or SYN|ACK transmits on TFO connections,
12845 * only include the TFO option if it is not a
12846 * retransmit, as the presence of the TFO option may
12847 * have caused the original SYN or SYN|ACK to have
12848 * been dropped by a middlebox.
12849 */
12850 if (IS_FASTOPEN(tp->t_flags) &&
12851 (tp->t_rxtshift == 0)) {
12852 if (tp->t_state == TCPS_SYN_RECEIVED) {
12853 to.to_tfo_len = TCP_FASTOPEN_COOKIE_LEN;
12854 to.to_tfo_cookie =
12855 (u_int8_t *)&tp->t_tfo_cookie.server;
12856 to.to_flags |= TOF_FASTOPEN;
12857 wanted_cookie = 1;
12858 } else if (tp->t_state == TCPS_SYN_SENT) {
12859 to.to_tfo_len =
12860 tp->t_tfo_client_cookie_len;
12861 to.to_tfo_cookie =
12862 tp->t_tfo_cookie.client;
12863 to.to_flags |= TOF_FASTOPEN;
12864 wanted_cookie = 1;
12865 }
12866 }
12867 }
12868 /* Window scaling. */
12869 if ((flags & TH_SYN) && (tp->t_flags & TF_REQ_SCALE)) {
12870 to.to_wscale = tp->request_r_scale;
12871 to.to_flags |= TOF_SCALE;
12872 }
12873 /* Timestamps. */
12874 if ((tp->t_flags & TF_RCVD_TSTMP) ||
12875 ((flags & TH_SYN) && (tp->t_flags & TF_REQ_TSTMP))) {
12876 to.to_tsval = tcp_tv_to_mssectick(&bbr->rc_tv) + tp->ts_offset;
12877 to.to_tsecr = tp->ts_recent;
12878 to.to_flags |= TOF_TS;
12879 local_options += TCPOLEN_TIMESTAMP + 2;
12880 }
12881 /* Set receive buffer autosizing timestamp. */
12882 if (tp->rfbuf_ts == 0 &&
12883 (so->so_rcv.sb_flags & SB_AUTOSIZE))
12884 tp->rfbuf_ts = tcp_tv_to_mssectick(&bbr->rc_tv);
12885 /* Selective ACK's. */
12886 if (flags & TH_SYN)
12887 to.to_flags |= TOF_SACKPERM;
12888 else if (TCPS_HAVEESTABLISHED(tp->t_state) &&
12889 tp->rcv_numsacks > 0) {
12890 to.to_flags |= TOF_SACK;
12891 to.to_nsacks = tp->rcv_numsacks;
12892 to.to_sacks = (u_char *)tp->sackblks;
12893 }
12894 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
12895 /* TCP-MD5 (RFC2385). */
12896 if (tp->t_flags & TF_SIGNATURE)
12897 to.to_flags |= TOF_SIGNATURE;
12898 #endif /* TCP_SIGNATURE */
12899
12900 /* Processing the options. */
12901 hdrlen += (optlen = tcp_addoptions(&to, opt));
12902 /*
12903 * If we wanted a TFO option to be added, but it was unable
12904 * to fit, ensure no data is sent.
12905 */
12906 if (IS_FASTOPEN(tp->t_flags) && wanted_cookie &&
12907 !(to.to_flags & TOF_FASTOPEN))
12908 len = 0;
12909 }
12910 if (tp->t_port) {
12911 if (V_tcp_udp_tunneling_port == 0) {
12912 /* The port was removed?? */
12913 SOCKBUF_UNLOCK(&so->so_snd);
12914 return (EHOSTUNREACH);
12915 }
12916 hdrlen += sizeof(struct udphdr);
12917 }
12918 #ifdef INET6
12919 if (isipv6)
12920 ipoptlen = ip6_optlen(inp);
12921 else
12922 #endif
12923 if (inp->inp_options)
12924 ipoptlen = inp->inp_options->m_len -
12925 offsetof(struct ipoption, ipopt_list);
12926 else
12927 ipoptlen = 0;
12928 ipoptlen = 0;
12929 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
12930 ipoptlen += ipsec_optlen;
12931 #endif
12932 if (bbr->rc_last_options != local_options) {
12933 /*
12934 * Cache the options length this generally does not change
12935 * on a connection. We use this to calculate TSO.
12936 */
12937 bbr->rc_last_options = local_options;
12938 }
12939 maxseg = tp->t_maxseg - (ipoptlen + optlen);
12940 p_maxseg = min(maxseg, pace_max_segs);
12941 /*
12942 * Adjust data length if insertion of options will bump the packet
12943 * length beyond the t_maxseg length. Clear the FIN bit because we
12944 * cut off the tail of the segment.
12945 */
12946 if (len > maxseg) {
12947 if (len != 0 && (flags & TH_FIN)) {
12948 flags &= ~TH_FIN;
12949 }
12950 if (tso) {
12951 uint32_t moff;
12952 int32_t max_len;
12953
12954 /* extract TSO information */
12955 if_hw_tsomax = tp->t_tsomax;
12956 if_hw_tsomaxsegcount = tp->t_tsomaxsegcount;
12957 if_hw_tsomaxsegsize = tp->t_tsomaxsegsize;
12958 KASSERT(ipoptlen == 0,
12959 ("%s: TSO can't do IP options", __func__));
12960
12961 /*
12962 * Check if we should limit by maximum payload
12963 * length:
12964 */
12965 if (if_hw_tsomax != 0) {
12966 /* compute maximum TSO length */
12967 max_len = (if_hw_tsomax - hdrlen -
12968 max_linkhdr);
12969 if (max_len <= 0) {
12970 len = 0;
12971 } else if (len > max_len) {
12972 len = max_len;
12973 }
12974 }
12975 /*
12976 * Prevent the last segment from being fractional
12977 * unless the send sockbuf can be emptied:
12978 */
12979 if ((sb_offset + len) < sbavail(sb)) {
12980 moff = len % (uint32_t)maxseg;
12981 if (moff != 0) {
12982 len -= moff;
12983 }
12984 }
12985 /*
12986 * In case there are too many small fragments don't
12987 * use TSO:
12988 */
12989 if (len <= maxseg) {
12990 len = maxseg;
12991 tso = 0;
12992 }
12993 } else {
12994 /* Not doing TSO */
12995 if (optlen + ipoptlen >= tp->t_maxseg) {
12996 /*
12997 * Since we don't have enough space to put
12998 * the IP header chain and the TCP header in
12999 * one packet as required by RFC 7112, don't
13000 * send it. Also ensure that at least one
13001 * byte of the payload can be put into the
13002 * TCP segment.
13003 */
13004 SOCKBUF_UNLOCK(&so->so_snd);
13005 error = EMSGSIZE;
13006 sack_rxmit = 0;
13007 goto out;
13008 }
13009 len = maxseg;
13010 }
13011 } else {
13012 /* Not doing TSO */
13013 if_hw_tsomaxsegcount = 0;
13014 tso = 0;
13015 }
13016 KASSERT(len + hdrlen + ipoptlen <= IP_MAXPACKET,
13017 ("%s: len > IP_MAXPACKET", __func__));
13018 #ifdef DIAGNOSTIC
13019 #ifdef INET6
13020 if (max_linkhdr + hdrlen > MCLBYTES)
13021 #else
13022 if (max_linkhdr + hdrlen > MHLEN)
13023 #endif
13024 panic("tcphdr too big");
13025 #endif
13026 /*
13027 * This KASSERT is here to catch edge cases at a well defined place.
13028 * Before, those had triggered (random) panic conditions further
13029 * down.
13030 */
13031 #ifdef BBR_INVARIANTS
13032 if (sack_rxmit) {
13033 if (SEQ_LT(rsm->r_start, tp->snd_una)) {
13034 panic("RSM:%p TP:%p bbr:%p start:%u is < snd_una:%u",
13035 rsm, tp, bbr, rsm->r_start, tp->snd_una);
13036 }
13037 }
13038 #endif
13039 KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__));
13040 if ((len == 0) &&
13041 (flags & TH_FIN) &&
13042 (sbused(sb))) {
13043 /*
13044 * We have outstanding data, don't send a fin by itself!.
13045 */
13046 slot = 0;
13047 goto just_return;
13048 }
13049 /*
13050 * Grab a header mbuf, attaching a copy of data to be transmitted,
13051 * and initialize the header from the template for sends on this
13052 * connection.
13053 */
13054 if (len) {
13055 uint32_t moff;
13056
13057 /*
13058 * We place a limit on sending with hptsi.
13059 */
13060 if ((rsm == NULL) && len > pace_max_segs)
13061 len = pace_max_segs;
13062 if (len <= maxseg)
13063 tso = 0;
13064 #ifdef INET6
13065 if (MHLEN < hdrlen + max_linkhdr)
13066 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
13067 else
13068 #endif
13069 m = m_gethdr(M_NOWAIT, MT_DATA);
13070
13071 if (m == NULL) {
13072 BBR_STAT_INC(bbr_failed_mbuf_aloc);
13073 bbr_log_enobuf_jmp(bbr, len, cts, __LINE__, len, 0, 0);
13074 SOCKBUF_UNLOCK(sb);
13075 error = ENOBUFS;
13076 sack_rxmit = 0;
13077 goto out;
13078 }
13079 m->m_data += max_linkhdr;
13080 m->m_len = hdrlen;
13081 /*
13082 * Start the m_copy functions from the closest mbuf to the
13083 * sb_offset in the socket buffer chain.
13084 */
13085 if ((sb_offset > sbavail(sb)) || ((len + sb_offset) > sbavail(sb))) {
13086 #ifdef BBR_INVARIANTS
13087 if ((len + sb_offset) > (sbavail(sb) + ((flags & (TH_FIN | TH_SYN)) ? 1 : 0)))
13088 panic("tp:%p bbr:%p len:%u sb_offset:%u sbavail:%u rsm:%p %u:%u:%u",
13089 tp, bbr, len, sb_offset, sbavail(sb), rsm,
13090 doing_retran_from,
13091 picked_up_retran,
13092 doing_tlp);
13093
13094 #endif
13095 /*
13096 * In this messed up situation we have two choices,
13097 * a) pretend the send worked, and just start timers
13098 * and what not (not good since that may lead us
13099 * back here a lot). <or> b) Send the lowest segment
13100 * in the map. <or> c) Drop the connection. Lets do
13101 * <b> which if it continues to happen will lead to
13102 * <c> via timeouts.
13103 */
13104 BBR_STAT_INC(bbr_offset_recovery);
13105 rsm = TAILQ_FIRST(&bbr->r_ctl.rc_map);
13106 sb_offset = 0;
13107 if (rsm == NULL) {
13108 sack_rxmit = 0;
13109 len = sbavail(sb);
13110 } else {
13111 sack_rxmit = 1;
13112 if (rsm->r_start != tp->snd_una) {
13113 /*
13114 * Things are really messed up, <c>
13115 * is the only thing to do.
13116 */
13117 BBR_STAT_INC(bbr_offset_drop);
13118 SOCKBUF_UNLOCK(sb);
13119 (void)m_free(m);
13120 return (-EFAULT); /* tcp_drop() */
13121 }
13122 len = rsm->r_end - rsm->r_start;
13123 }
13124 if (len > sbavail(sb))
13125 len = sbavail(sb);
13126 if (len > maxseg)
13127 len = maxseg;
13128 }
13129 mb = sbsndptr_noadv(sb, sb_offset, &moff);
13130 if (len <= MHLEN - hdrlen - max_linkhdr && !hw_tls) {
13131 m_copydata(mb, moff, (int)len,
13132 mtod(m, caddr_t)+hdrlen);
13133 if (rsm == NULL)
13134 sbsndptr_adv(sb, mb, len);
13135 m->m_len += len;
13136 } else {
13137 struct sockbuf *msb;
13138
13139 if (rsm)
13140 msb = NULL;
13141 else
13142 msb = sb;
13143 #ifdef BBR_INVARIANTS
13144 if ((len + moff) > (sbavail(sb) + ((flags & (TH_FIN | TH_SYN)) ? 1 : 0))) {
13145 if (rsm) {
13146 panic("tp:%p bbr:%p len:%u moff:%u sbavail:%u rsm:%p snd_una:%u rsm_start:%u flg:%x %u:%u:%u sr:%d ",
13147 tp, bbr, len, moff,
13148 sbavail(sb), rsm,
13149 tp->snd_una, rsm->r_flags, rsm->r_start,
13150 doing_retran_from,
13151 picked_up_retran,
13152 doing_tlp, sack_rxmit);
13153 } else {
13154 panic("tp:%p bbr:%p len:%u moff:%u sbavail:%u sb_offset:%u snd_una:%u",
13155 tp, bbr, len, moff, sbavail(sb), sb_offset, tp->snd_una);
13156 }
13157 }
13158 #endif
13159 m->m_next = tcp_m_copym(
13160 mb, moff, &len,
13161 if_hw_tsomaxsegcount,
13162 if_hw_tsomaxsegsize, msb,
13163 ((rsm == NULL) ? hw_tls : 0)
13164 #ifdef NETFLIX_COPY_ARGS
13165 , &filled_all
13166 #endif
13167 );
13168 if (len <= maxseg) {
13169 /*
13170 * Must have ran out of mbufs for the copy
13171 * shorten it to no longer need tso. Lets
13172 * not put on sendalot since we are low on
13173 * mbufs.
13174 */
13175 tso = 0;
13176 }
13177 if (m->m_next == NULL) {
13178 SOCKBUF_UNLOCK(sb);
13179 (void)m_free(m);
13180 error = ENOBUFS;
13181 sack_rxmit = 0;
13182 goto out;
13183 }
13184 }
13185 #ifdef BBR_INVARIANTS
13186 if (tso && len < maxseg) {
13187 panic("tp:%p tso on, but len:%d < maxseg:%d",
13188 tp, len, maxseg);
13189 }
13190 if (tso && if_hw_tsomaxsegcount) {
13191 int32_t seg_cnt = 0;
13192 struct mbuf *foo;
13193
13194 foo = m;
13195 while (foo) {
13196 seg_cnt++;
13197 foo = foo->m_next;
13198 }
13199 if (seg_cnt > if_hw_tsomaxsegcount) {
13200 panic("seg_cnt:%d > max:%d", seg_cnt, if_hw_tsomaxsegcount);
13201 }
13202 }
13203 #endif
13204 /*
13205 * If we're sending everything we've got, set PUSH. (This
13206 * will keep happy those implementations which only give
13207 * data to the user when a buffer fills or a PUSH comes in.)
13208 */
13209 if (sb_offset + len == sbused(sb) &&
13210 sbused(sb) &&
13211 !(flags & TH_SYN)) {
13212 flags |= TH_PUSH;
13213 }
13214 SOCKBUF_UNLOCK(sb);
13215 } else {
13216 SOCKBUF_UNLOCK(sb);
13217 if (tp->t_flags & TF_ACKNOW)
13218 KMOD_TCPSTAT_INC(tcps_sndacks);
13219 else if (flags & (TH_SYN | TH_FIN | TH_RST))
13220 KMOD_TCPSTAT_INC(tcps_sndctrl);
13221 else
13222 KMOD_TCPSTAT_INC(tcps_sndwinup);
13223
13224 m = m_gethdr(M_NOWAIT, MT_DATA);
13225 if (m == NULL) {
13226 BBR_STAT_INC(bbr_failed_mbuf_aloc);
13227 bbr_log_enobuf_jmp(bbr, len, cts, __LINE__, len, 0, 0);
13228 error = ENOBUFS;
13229 /* Fudge the send time since we could not send */
13230 sack_rxmit = 0;
13231 goto out;
13232 }
13233 #ifdef INET6
13234 if (isipv6 && (MHLEN < hdrlen + max_linkhdr) &&
13235 MHLEN >= hdrlen) {
13236 M_ALIGN(m, hdrlen);
13237 } else
13238 #endif
13239 m->m_data += max_linkhdr;
13240 m->m_len = hdrlen;
13241 }
13242 SOCKBUF_UNLOCK_ASSERT(sb);
13243 m->m_pkthdr.rcvif = (struct ifnet *)0;
13244 #ifdef MAC
13245 mac_inpcb_create_mbuf(inp, m);
13246 #endif
13247 #ifdef INET6
13248 if (isipv6) {
13249 ip6 = mtod(m, struct ip6_hdr *);
13250 if (tp->t_port) {
13251 udp = (struct udphdr *)((caddr_t)ip6 + sizeof(struct ip6_hdr));
13252 udp->uh_sport = htons(V_tcp_udp_tunneling_port);
13253 udp->uh_dport = tp->t_port;
13254 ulen = hdrlen + len - sizeof(struct ip6_hdr);
13255 udp->uh_ulen = htons(ulen);
13256 th = (struct tcphdr *)(udp + 1);
13257 } else {
13258 th = (struct tcphdr *)(ip6 + 1);
13259 }
13260 tcpip_fillheaders(inp, tp->t_port, ip6, th);
13261 } else
13262 #endif /* INET6 */
13263 {
13264 ip = mtod(m, struct ip *);
13265 if (tp->t_port) {
13266 udp = (struct udphdr *)((caddr_t)ip + sizeof(struct ip));
13267 udp->uh_sport = htons(V_tcp_udp_tunneling_port);
13268 udp->uh_dport = tp->t_port;
13269 ulen = hdrlen + len - sizeof(struct ip);
13270 udp->uh_ulen = htons(ulen);
13271 th = (struct tcphdr *)(udp + 1);
13272 } else {
13273 th = (struct tcphdr *)(ip + 1);
13274 }
13275 tcpip_fillheaders(inp, tp->t_port, ip, th);
13276 }
13277 /*
13278 * If we are doing retransmissions, then snd_nxt will not reflect
13279 * the first unsent octet. For ACK only packets, we do not want the
13280 * sequence number of the retransmitted packet, we want the sequence
13281 * number of the next unsent octet. So, if there is no data (and no
13282 * SYN or FIN), use snd_max instead of snd_nxt when filling in
13283 * ti_seq. But if we are in persist state, snd_max might reflect
13284 * one byte beyond the right edge of the window, so use snd_nxt in
13285 * that case, since we know we aren't doing a retransmission.
13286 * (retransmit and persist are mutually exclusive...)
13287 */
13288 if (sack_rxmit == 0) {
13289 if (len && ((flags & (TH_FIN | TH_SYN | TH_RST)) == 0)) {
13290 /* New data (including new persists) */
13291 th->th_seq = htonl(tp->snd_max);
13292 bbr_seq = tp->snd_max;
13293 } else if (flags & TH_SYN) {
13294 /* Syn's always send from iss */
13295 th->th_seq = htonl(tp->iss);
13296 bbr_seq = tp->iss;
13297 } else if (flags & TH_FIN) {
13298 if (flags & TH_FIN && tp->t_flags & TF_SENTFIN) {
13299 /*
13300 * If we sent the fin already its 1 minus
13301 * snd_max
13302 */
13303 th->th_seq = (htonl(tp->snd_max - 1));
13304 bbr_seq = (tp->snd_max - 1);
13305 } else {
13306 /* First time FIN use snd_max */
13307 th->th_seq = htonl(tp->snd_max);
13308 bbr_seq = tp->snd_max;
13309 }
13310 } else {
13311 /*
13312 * len == 0 and not persist we use snd_max, sending
13313 * an ack unless we have sent the fin then its 1
13314 * minus.
13315 */
13316 /*
13317 * XXXRRS Question if we are in persists and we have
13318 * nothing outstanding to send and we have not sent
13319 * a FIN, we will send an ACK. In such a case it
13320 * might be better to send (tp->snd_una - 1) which
13321 * would force the peer to ack.
13322 */
13323 if (tp->t_flags & TF_SENTFIN) {
13324 th->th_seq = htonl(tp->snd_max - 1);
13325 bbr_seq = (tp->snd_max - 1);
13326 } else {
13327 th->th_seq = htonl(tp->snd_max);
13328 bbr_seq = tp->snd_max;
13329 }
13330 }
13331 } else {
13332 /* All retransmits use the rsm to guide the send */
13333 th->th_seq = htonl(rsm->r_start);
13334 bbr_seq = rsm->r_start;
13335 }
13336 th->th_ack = htonl(tp->rcv_nxt);
13337 if (optlen) {
13338 bcopy(opt, th + 1, optlen);
13339 th->th_off = (sizeof(struct tcphdr) + optlen) >> 2;
13340 }
13341 tcp_set_flags(th, flags);
13342 /*
13343 * Calculate receive window. Don't shrink window, but avoid silly
13344 * window syndrome.
13345 */
13346 if ((flags & TH_RST) || ((recwin < (so->so_rcv.sb_hiwat / 4) &&
13347 recwin < maxseg)))
13348 recwin = 0;
13349 if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt) &&
13350 recwin < (tp->rcv_adv - tp->rcv_nxt))
13351 recwin = (tp->rcv_adv - tp->rcv_nxt);
13352 if (recwin > TCP_MAXWIN << tp->rcv_scale)
13353 recwin = TCP_MAXWIN << tp->rcv_scale;
13354
13355 /*
13356 * According to RFC1323 the window field in a SYN (i.e., a <SYN> or
13357 * <SYN,ACK>) segment itself is never scaled. The <SYN,ACK> case is
13358 * handled in syncache.
13359 */
13360 if (flags & TH_SYN)
13361 th->th_win = htons((u_short)
13362 (min(sbspace(&so->so_rcv), TCP_MAXWIN)));
13363 else {
13364 /* Avoid shrinking window with window scaling. */
13365 recwin = roundup2(recwin, 1 << tp->rcv_scale);
13366 th->th_win = htons((u_short)(recwin >> tp->rcv_scale));
13367 }
13368 /*
13369 * Adjust the RXWIN0SENT flag - indicate that we have advertised a 0
13370 * window. This may cause the remote transmitter to stall. This
13371 * flag tells soreceive() to disable delayed acknowledgements when
13372 * draining the buffer. This can occur if the receiver is
13373 * attempting to read more data than can be buffered prior to
13374 * transmitting on the connection.
13375 */
13376 if (th->th_win == 0) {
13377 tp->t_sndzerowin++;
13378 tp->t_flags |= TF_RXWIN0SENT;
13379 } else
13380 tp->t_flags &= ~TF_RXWIN0SENT;
13381 /*
13382 * We don't support urgent data, but drag along
13383 * the pointer in case of a stack switch.
13384 */
13385 tp->snd_up = tp->snd_una;
13386
13387 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
13388 if (to.to_flags & TOF_SIGNATURE) {
13389 /*
13390 * Calculate MD5 signature and put it into the place
13391 * determined before. NOTE: since TCP options buffer doesn't
13392 * point into mbuf's data, calculate offset and use it.
13393 */
13394 if (!TCPMD5_ENABLED() || TCPMD5_OUTPUT(m, th,
13395 (u_char *)(th + 1) + (to.to_signature - opt)) != 0) {
13396 /*
13397 * Do not send segment if the calculation of MD5
13398 * digest has failed.
13399 */
13400 goto out;
13401 }
13402 }
13403 #endif
13404
13405 /*
13406 * Put TCP length in extended header, and then checksum extended
13407 * header and data.
13408 */
13409 m->m_pkthdr.len = hdrlen + len; /* in6_cksum() need this */
13410 #ifdef INET6
13411 if (isipv6) {
13412 /*
13413 * ip6_plen is not need to be filled now, and will be filled
13414 * in ip6_output.
13415 */
13416 if (tp->t_port) {
13417 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
13418 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
13419 udp->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0);
13420 th->th_sum = htons(0);
13421 UDPSTAT_INC(udps_opackets);
13422 } else {
13423 csum_flags = m->m_pkthdr.csum_flags = CSUM_TCP_IPV6;
13424 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
13425 th->th_sum = in6_cksum_pseudo(ip6, sizeof(struct tcphdr) +
13426 optlen + len, IPPROTO_TCP, 0);
13427 }
13428 }
13429 #endif
13430 #if defined(INET6) && defined(INET)
13431 else
13432 #endif
13433 #ifdef INET
13434 {
13435 if (tp->t_port) {
13436 m->m_pkthdr.csum_flags = CSUM_UDP;
13437 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
13438 udp->uh_sum = in_pseudo(ip->ip_src.s_addr,
13439 ip->ip_dst.s_addr, htons(ulen + IPPROTO_UDP));
13440 th->th_sum = htons(0);
13441 UDPSTAT_INC(udps_opackets);
13442 } else {
13443 csum_flags = m->m_pkthdr.csum_flags = CSUM_TCP;
13444 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
13445 th->th_sum = in_pseudo(ip->ip_src.s_addr,
13446 ip->ip_dst.s_addr, htons(sizeof(struct tcphdr) +
13447 IPPROTO_TCP + len + optlen));
13448 }
13449 /* IP version must be set here for ipv4/ipv6 checking later */
13450 KASSERT(ip->ip_v == IPVERSION,
13451 ("%s: IP version incorrect: %d", __func__, ip->ip_v));
13452 }
13453 #endif
13454
13455 /*
13456 * Enable TSO and specify the size of the segments. The TCP pseudo
13457 * header checksum is always provided. XXX: Fixme: This is currently
13458 * not the case for IPv6.
13459 */
13460 if (tso) {
13461 KASSERT(len > maxseg,
13462 ("%s: len:%d <= tso_segsz:%d", __func__, len, maxseg));
13463 m->m_pkthdr.csum_flags |= CSUM_TSO;
13464 csum_flags |= CSUM_TSO;
13465 m->m_pkthdr.tso_segsz = maxseg;
13466 }
13467 KASSERT(len + hdrlen == m_length(m, NULL),
13468 ("%s: mbuf chain different than expected: %d + %u != %u",
13469 __func__, len, hdrlen, m_length(m, NULL)));
13470
13471 #ifdef TCP_HHOOK
13472 /* Run HHOOK_TC_ESTABLISHED_OUT helper hooks. */
13473 hhook_run_tcp_est_out(tp, th, &to, len, tso);
13474 #endif
13475
13476 /* Log to the black box */
13477 if (tp->t_logstate != TCP_LOG_STATE_OFF) {
13478 union tcp_log_stackspecific log;
13479
13480 bbr_fill_in_logging_data(bbr, &log.u_bbr, cts);
13481 /* Record info on type of transmission */
13482 log.u_bbr.flex1 = bbr->r_ctl.rc_hptsi_agg_delay;
13483 log.u_bbr.flex2 = (bbr->r_recovery_bw << 3);
13484 log.u_bbr.flex3 = maxseg;
13485 log.u_bbr.flex4 = delay_calc;
13486 /* Encode filled_all into the upper flex5 bit */
13487 log.u_bbr.flex5 = bbr->rc_past_init_win;
13488 log.u_bbr.flex5 <<= 1;
13489 log.u_bbr.flex5 |= bbr->rc_no_pacing;
13490 log.u_bbr.flex5 <<= 29;
13491 if (filled_all)
13492 log.u_bbr.flex5 |= 0x80000000;
13493 log.u_bbr.flex5 |= tp->t_maxseg;
13494 log.u_bbr.flex6 = bbr->r_ctl.rc_pace_max_segs;
13495 log.u_bbr.flex7 = (bbr->rc_bbr_state << 8) | bbr_state_val(bbr);
13496 /* lets poke in the low and the high here for debugging */
13497 log.u_bbr.pkts_out = bbr->rc_tp->t_maxseg;
13498 if (rsm || sack_rxmit) {
13499 if (doing_tlp)
13500 log.u_bbr.flex8 = 2;
13501 else
13502 log.u_bbr.flex8 = 1;
13503 } else {
13504 log.u_bbr.flex8 = 0;
13505 }
13506 lgb = tcp_log_event_(tp, th, &so->so_rcv, &so->so_snd, TCP_LOG_OUT, ERRNO_UNK,
13507 len, &log, false, NULL, NULL, 0, tv);
13508 } else {
13509 lgb = NULL;
13510 }
13511 /*
13512 * Fill in IP length and desired time to live and send to IP level.
13513 * There should be a better way to handle ttl and tos; we could keep
13514 * them in the template, but need a way to checksum without them.
13515 */
13516 /*
13517 * m->m_pkthdr.len should have been set before cksum calcuration,
13518 * because in6_cksum() need it.
13519 */
13520 #ifdef INET6
13521 if (isipv6) {
13522 /*
13523 * we separately set hoplimit for every segment, since the
13524 * user might want to change the value via setsockopt. Also,
13525 * desired default hop limit might be changed via Neighbor
13526 * Discovery.
13527 */
13528 ip6->ip6_hlim = in6_selecthlim(inp, NULL);
13529
13530 /*
13531 * Set the packet size here for the benefit of DTrace
13532 * probes. ip6_output() will set it properly; it's supposed
13533 * to include the option header lengths as well.
13534 */
13535 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6));
13536
13537 if (V_path_mtu_discovery && maxseg > V_tcp_minmss)
13538 tp->t_flags2 |= TF2_PLPMTU_PMTUD;
13539 else
13540 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD;
13541
13542 if (tp->t_state == TCPS_SYN_SENT)
13543 TCP_PROBE5(connect__request, NULL, tp, ip6, tp, th);
13544
13545 TCP_PROBE5(send, NULL, tp, ip6, tp, th);
13546 /* TODO: IPv6 IP6TOS_ECT bit on */
13547 error = ip6_output(m, inp->in6p_outputopts,
13548 &inp->inp_route6,
13549 ((rsm || sack_rxmit) ? IP_NO_SND_TAG_RL : 0),
13550 NULL, NULL, inp);
13551
13552 if (error == EMSGSIZE && inp->inp_route6.ro_nh != NULL)
13553 mtu = inp->inp_route6.ro_nh->nh_mtu;
13554 }
13555 #endif /* INET6 */
13556 #if defined(INET) && defined(INET6)
13557 else
13558 #endif
13559 #ifdef INET
13560 {
13561 ip->ip_len = htons(m->m_pkthdr.len);
13562 #ifdef INET6
13563 if (isipv6)
13564 ip->ip_ttl = in6_selecthlim(inp, NULL);
13565 #endif /* INET6 */
13566 /*
13567 * If we do path MTU discovery, then we set DF on every
13568 * packet. This might not be the best thing to do according
13569 * to RFC3390 Section 2. However the tcp hostcache migitates
13570 * the problem so it affects only the first tcp connection
13571 * with a host.
13572 *
13573 * NB: Don't set DF on small MTU/MSS to have a safe
13574 * fallback.
13575 */
13576 if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) {
13577 tp->t_flags2 |= TF2_PLPMTU_PMTUD;
13578 if (tp->t_port == 0 || len < V_tcp_minmss) {
13579 ip->ip_off |= htons(IP_DF);
13580 }
13581 } else {
13582 tp->t_flags2 &= ~TF2_PLPMTU_PMTUD;
13583 }
13584
13585 if (tp->t_state == TCPS_SYN_SENT)
13586 TCP_PROBE5(connect__request, NULL, tp, ip, tp, th);
13587
13588 TCP_PROBE5(send, NULL, tp, ip, tp, th);
13589
13590 error = ip_output(m, inp->inp_options, &inp->inp_route,
13591 ((rsm || sack_rxmit) ? IP_NO_SND_TAG_RL : 0), 0,
13592 inp);
13593 if (error == EMSGSIZE && inp->inp_route.ro_nh != NULL)
13594 mtu = inp->inp_route.ro_nh->nh_mtu;
13595 }
13596 #endif /* INET */
13597 out:
13598
13599 if (lgb) {
13600 lgb->tlb_errno = error;
13601 lgb = NULL;
13602 }
13603 /*
13604 * In transmit state, time the transmission and arrange for the
13605 * retransmit. In persist state, just set snd_max.
13606 */
13607 if (error == 0) {
13608 tcp_account_for_send(tp, len, (rsm != NULL), doing_tlp, hw_tls);
13609 if (TCPS_HAVEESTABLISHED(tp->t_state) &&
13610 (tp->t_flags & TF_SACK_PERMIT) &&
13611 tp->rcv_numsacks > 0)
13612 tcp_clean_dsack_blocks(tp);
13613 /* We sent an ack clear the bbr_segs_rcvd count */
13614 bbr->output_error_seen = 0;
13615 bbr->oerror_cnt = 0;
13616 bbr->bbr_segs_rcvd = 0;
13617 if (len == 0)
13618 counter_u64_add(bbr_out_size[TCP_MSS_ACCT_SNDACK], 1);
13619 /* Do accounting for new sends */
13620 if ((len > 0) && (rsm == NULL)) {
13621 int idx;
13622 if (tp->snd_una == tp->snd_max) {
13623 /*
13624 * Special case to match google, when
13625 * nothing is in flight the delivered
13626 * time does get updated to the current
13627 * time (see tcp_rate_bsd.c).
13628 */
13629 bbr->r_ctl.rc_del_time = cts;
13630 }
13631 if (len >= maxseg) {
13632 idx = (len / maxseg) + 3;
13633 if (idx >= TCP_MSS_ACCT_ATIMER)
13634 counter_u64_add(bbr_out_size[(TCP_MSS_ACCT_ATIMER - 1)], 1);
13635 else
13636 counter_u64_add(bbr_out_size[idx], 1);
13637 } else {
13638 /* smaller than a MSS */
13639 idx = len / (bbr_hptsi_bytes_min - bbr->rc_last_options);
13640 if (idx >= TCP_MSS_SMALL_MAX_SIZE_DIV)
13641 idx = (TCP_MSS_SMALL_MAX_SIZE_DIV - 1);
13642 counter_u64_add(bbr_out_size[(idx + TCP_MSS_SMALL_SIZE_OFF)], 1);
13643 }
13644 }
13645 }
13646 abandon = 0;
13647 /*
13648 * We must do the send accounting before we log the output,
13649 * otherwise the state of the rsm could change and we account to the
13650 * wrong bucket.
13651 */
13652 if (len > 0) {
13653 bbr_do_send_accounting(tp, bbr, rsm, len, error);
13654 if (error == 0) {
13655 if (tp->snd_una == tp->snd_max)
13656 bbr->r_ctl.rc_tlp_rxt_last_time = cts;
13657 }
13658 }
13659 bbr_log_output(bbr, tp, &to, len, bbr_seq, (uint8_t) flags, error,
13660 cts, mb, &abandon, rsm, 0, sb);
13661 if (abandon) {
13662 /*
13663 * If bbr_log_output destroys the TCB or sees a TH_RST being
13664 * sent we should hit this condition.
13665 */
13666 return (0);
13667 }
13668 if (bbr->rc_in_persist == 0) {
13669 /*
13670 * Advance snd_nxt over sequence space of this segment.
13671 */
13672 if (error)
13673 /* We don't log or do anything with errors */
13674 goto skip_upd;
13675
13676 if (tp->snd_una == tp->snd_max &&
13677 (len || (flags & (TH_SYN | TH_FIN)))) {
13678 /*
13679 * Update the time we just added data since none was
13680 * outstanding.
13681 */
13682 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_START, __LINE__);
13683 bbr->rc_tp->t_acktime = ticks;
13684 }
13685 if (flags & (TH_SYN | TH_FIN) && (rsm == NULL)) {
13686 if (flags & TH_SYN) {
13687 /*
13688 * Smack the snd_max to iss + 1
13689 * if its a FO we will add len below.
13690 */
13691 tp->snd_max = tp->iss + 1;
13692 }
13693 if ((flags & TH_FIN) && ((tp->t_flags & TF_SENTFIN) == 0)) {
13694 tp->snd_max++;
13695 tp->t_flags |= TF_SENTFIN;
13696 }
13697 }
13698 if (sack_rxmit == 0)
13699 tp->snd_max += len;
13700 skip_upd:
13701 if ((error == 0) && len)
13702 tot_len += len;
13703 } else {
13704 /* Persists case */
13705 int32_t xlen = len;
13706
13707 if (error)
13708 goto nomore;
13709
13710 if (flags & TH_SYN)
13711 ++xlen;
13712 if ((flags & TH_FIN) && ((tp->t_flags & TF_SENTFIN) == 0)) {
13713 ++xlen;
13714 tp->t_flags |= TF_SENTFIN;
13715 }
13716 if (xlen && (tp->snd_una == tp->snd_max)) {
13717 /*
13718 * Update the time we just added data since none was
13719 * outstanding.
13720 */
13721 bbr_log_progress_event(bbr, tp, ticks, PROGRESS_START, __LINE__);
13722 bbr->rc_tp->t_acktime = ticks;
13723 }
13724 if (sack_rxmit == 0)
13725 tp->snd_max += xlen;
13726 tot_len += (len + optlen + ipoptlen);
13727 }
13728 nomore:
13729 if (error) {
13730 /*
13731 * Failures do not advance the seq counter above. For the
13732 * case of ENOBUFS we will fall out and become ack-clocked.
13733 * capping the cwnd at the current flight.
13734 * Everything else will just have to retransmit with the timer
13735 * (no pacer).
13736 */
13737 SOCKBUF_UNLOCK_ASSERT(sb);
13738 BBR_STAT_INC(bbr_saw_oerr);
13739 /* Clear all delay/early tracks */
13740 bbr->r_ctl.rc_hptsi_agg_delay = 0;
13741 bbr->r_ctl.rc_agg_early = 0;
13742 bbr->r_agg_early_set = 0;
13743 bbr->output_error_seen = 1;
13744 if (bbr->oerror_cnt < 0xf)
13745 bbr->oerror_cnt++;
13746 if (bbr_max_net_error_cnt && (bbr->oerror_cnt >= bbr_max_net_error_cnt)) {
13747 /* drop the session */
13748 return (-ENETDOWN);
13749 }
13750 switch (error) {
13751 case ENOBUFS:
13752 /*
13753 * Make this guy have to get ack's to send
13754 * more but lets make sure we don't
13755 * slam him below a T-O (1MSS).
13756 */
13757 if (bbr->rc_bbr_state != BBR_STATE_PROBE_RTT) {
13758 tp->snd_cwnd = ctf_flight_size(tp, (bbr->r_ctl.rc_sacked +
13759 bbr->r_ctl.rc_lost_bytes)) - maxseg;
13760 if (tp->snd_cwnd < maxseg)
13761 tp->snd_cwnd = maxseg;
13762 }
13763 slot = (bbr_error_base_paceout + 1) << bbr->oerror_cnt;
13764 BBR_STAT_INC(bbr_saw_enobuf);
13765 if (bbr->bbr_hdrw_pacing)
13766 counter_u64_add(bbr_hdwr_pacing_enobuf, 1);
13767 else
13768 counter_u64_add(bbr_nohdwr_pacing_enobuf, 1);
13769 /*
13770 * Here even in the enobuf's case we want to do our
13771 * state update. The reason being we may have been
13772 * called by the input function. If so we have had
13773 * things change.
13774 */
13775 error = 0;
13776 goto enobufs;
13777 case EMSGSIZE:
13778 /*
13779 * For some reason the interface we used initially
13780 * to send segments changed to another or lowered
13781 * its MTU. If TSO was active we either got an
13782 * interface without TSO capabilits or TSO was
13783 * turned off. If we obtained mtu from ip_output()
13784 * then update it and try again.
13785 */
13786 /* Turn on tracing (or try to) */
13787 {
13788 int old_maxseg;
13789
13790 old_maxseg = tp->t_maxseg;
13791 BBR_STAT_INC(bbr_saw_emsgsiz);
13792 bbr_log_msgsize_fail(bbr, tp, len, maxseg, mtu, csum_flags, tso, cts);
13793 if (mtu != 0)
13794 tcp_mss_update(tp, -1, mtu, NULL, NULL);
13795 if (old_maxseg <= tp->t_maxseg) {
13796 /* Huh it did not shrink? */
13797 tp->t_maxseg = old_maxseg - 40;
13798 bbr_log_msgsize_fail(bbr, tp, len, maxseg, mtu, 0, tso, cts);
13799 }
13800 /*
13801 * Nuke all other things that can interfere
13802 * with slot
13803 */
13804 if ((tot_len + len) && (len >= tp->t_maxseg)) {
13805 slot = bbr_get_pacing_delay(bbr,
13806 bbr->r_ctl.rc_bbr_hptsi_gain,
13807 (tot_len + len), cts, 0);
13808 if (slot < bbr_error_base_paceout)
13809 slot = (bbr_error_base_paceout + 2) << bbr->oerror_cnt;
13810 } else
13811 slot = (bbr_error_base_paceout + 2) << bbr->oerror_cnt;
13812 bbr->rc_output_starts_timer = 1;
13813 bbr_start_hpts_timer(bbr, tp, cts, 10, slot,
13814 tot_len);
13815 return (error);
13816 }
13817 case EPERM:
13818 tp->t_softerror = error;
13819 /* Fall through */
13820 case EHOSTDOWN:
13821 case EHOSTUNREACH:
13822 case ENETDOWN:
13823 case ENETUNREACH:
13824 if (TCPS_HAVERCVDSYN(tp->t_state)) {
13825 tp->t_softerror = error;
13826 }
13827 /* FALLTHROUGH */
13828 default:
13829 slot = (bbr_error_base_paceout + 3) << bbr->oerror_cnt;
13830 bbr->rc_output_starts_timer = 1;
13831 bbr_start_hpts_timer(bbr, tp, cts, 11, slot, 0);
13832 return (error);
13833 }
13834 #ifdef STATS
13835 } else if (((tp->t_flags & TF_GPUTINPROG) == 0) &&
13836 len &&
13837 (rsm == NULL) &&
13838 (bbr->rc_in_persist == 0)) {
13839 tp->gput_seq = bbr_seq;
13840 tp->gput_ack = bbr_seq +
13841 min(sbavail(&so->so_snd) - sb_offset, sendwin);
13842 tp->gput_ts = cts;
13843 tp->t_flags |= TF_GPUTINPROG;
13844 #endif
13845 }
13846 KMOD_TCPSTAT_INC(tcps_sndtotal);
13847 if ((bbr->bbr_hdw_pace_ena) &&
13848 (bbr->bbr_attempt_hdwr_pace == 0) &&
13849 (bbr->rc_past_init_win) &&
13850 (bbr->rc_bbr_state != BBR_STATE_STARTUP) &&
13851 (get_filter_value(&bbr->r_ctl.rc_delrate)) &&
13852 (inp->inp_route.ro_nh &&
13853 inp->inp_route.ro_nh->nh_ifp)) {
13854 /*
13855 * We are past the initial window and
13856 * have at least one measurement so we
13857 * could use hardware pacing if its available.
13858 * We have an interface and we have not attempted
13859 * to setup hardware pacing, lets try to now.
13860 */
13861 uint64_t rate_wanted;
13862 int err = 0;
13863
13864 rate_wanted = bbr_get_hardware_rate(bbr);
13865 bbr->bbr_attempt_hdwr_pace = 1;
13866 bbr->r_ctl.crte = tcp_set_pacing_rate(bbr->rc_tp,
13867 inp->inp_route.ro_nh->nh_ifp,
13868 rate_wanted,
13869 (RS_PACING_GEQ|RS_PACING_SUB_OK),
13870 &err, NULL);
13871 if (bbr->r_ctl.crte) {
13872 bbr_type_log_hdwr_pacing(bbr,
13873 bbr->r_ctl.crte->ptbl->rs_ifp,
13874 rate_wanted,
13875 bbr->r_ctl.crte->rate,
13876 __LINE__, cts, err);
13877 BBR_STAT_INC(bbr_hdwr_rl_add_ok);
13878 counter_u64_add(bbr_flows_nohdwr_pacing, -1);
13879 counter_u64_add(bbr_flows_whdwr_pacing, 1);
13880 bbr->bbr_hdrw_pacing = 1;
13881 /* Now what is our gain status? */
13882 if (bbr->r_ctl.crte->rate < rate_wanted) {
13883 /* We have a problem */
13884 bbr_setup_less_of_rate(bbr, cts,
13885 bbr->r_ctl.crte->rate, rate_wanted);
13886 } else {
13887 /* We are good */
13888 bbr->gain_is_limited = 0;
13889 bbr->skip_gain = 0;
13890 }
13891 tcp_bbr_tso_size_check(bbr, cts);
13892 } else {
13893 bbr_type_log_hdwr_pacing(bbr,
13894 inp->inp_route.ro_nh->nh_ifp,
13895 rate_wanted,
13896 0,
13897 __LINE__, cts, err);
13898 BBR_STAT_INC(bbr_hdwr_rl_add_fail);
13899 }
13900 }
13901 if (bbr->bbr_hdrw_pacing) {
13902 /*
13903 * Worry about cases where the route
13904 * changes or something happened that we
13905 * lost our hardware pacing possibly during
13906 * the last ip_output call.
13907 */
13908 if (inp->inp_snd_tag == NULL) {
13909 /* A change during ip output disabled hw pacing? */
13910 bbr->bbr_hdrw_pacing = 0;
13911 } else if ((inp->inp_route.ro_nh == NULL) ||
13912 (inp->inp_route.ro_nh->nh_ifp != inp->inp_snd_tag->ifp)) {
13913 /*
13914 * We had an interface or route change,
13915 * detach from the current hdwr pacing
13916 * and setup to re-attempt next go
13917 * round.
13918 */
13919 bbr->bbr_hdrw_pacing = 0;
13920 bbr->bbr_attempt_hdwr_pace = 0;
13921 tcp_rel_pacing_rate(bbr->r_ctl.crte, bbr->rc_tp);
13922 tcp_bbr_tso_size_check(bbr, cts);
13923 }
13924 }
13925 /*
13926 * Data sent (as far as we can tell). If this advertises a larger
13927 * window than any other segment, then remember the size of the
13928 * advertised window. Any pending ACK has now been sent.
13929 */
13930 if (SEQ_GT(tp->rcv_nxt + recwin, tp->rcv_adv))
13931 tp->rcv_adv = tp->rcv_nxt + recwin;
13932
13933 tp->last_ack_sent = tp->rcv_nxt;
13934 if ((error == 0) &&
13935 (bbr->r_ctl.rc_pace_max_segs > tp->t_maxseg) &&
13936 (doing_tlp == 0) &&
13937 (tso == 0) &&
13938 (len > 0) &&
13939 ((flags & TH_RST) == 0) &&
13940 ((flags & TH_SYN) == 0) &&
13941 (IN_RECOVERY(tp->t_flags) == 0) &&
13942 (bbr->rc_in_persist == 0) &&
13943 (tot_len < bbr->r_ctl.rc_pace_max_segs)) {
13944 /*
13945 * For non-tso we need to goto again until we have sent out
13946 * enough data to match what we are hptsi out every hptsi
13947 * interval.
13948 */
13949 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) {
13950 /* Make sure snd_nxt is drug up */
13951 tp->snd_nxt = tp->snd_max;
13952 }
13953 if (rsm != NULL) {
13954 rsm = NULL;
13955 goto skip_again;
13956 }
13957 rsm = NULL;
13958 sack_rxmit = 0;
13959 tp->t_flags &= ~(TF_ACKNOW | TF_DELACK);
13960 goto again;
13961 }
13962 skip_again:
13963 if ((error == 0) && (flags & TH_FIN))
13964 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_FIN);
13965 if ((error == 0) && (flags & TH_RST))
13966 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST);
13967 if (((flags & (TH_RST | TH_SYN | TH_FIN)) == 0) && tot_len) {
13968 /*
13969 * Calculate/Re-Calculate the hptsi slot in usecs based on
13970 * what we have sent so far
13971 */
13972 slot = bbr_get_pacing_delay(bbr, bbr->r_ctl.rc_bbr_hptsi_gain, tot_len, cts, 0);
13973 if (bbr->rc_no_pacing)
13974 slot = 0;
13975 }
13976 tp->t_flags &= ~(TF_ACKNOW | TF_DELACK);
13977 enobufs:
13978 if (bbr->rc_use_google == 0)
13979 bbr_check_bbr_for_state(bbr, cts, __LINE__, 0);
13980 bbr_cwnd_limiting(tp, bbr, ctf_flight_size(tp, (bbr->r_ctl.rc_sacked +
13981 bbr->r_ctl.rc_lost_bytes)));
13982 bbr->rc_output_starts_timer = 1;
13983 if (bbr->bbr_use_rack_cheat &&
13984 (more_to_rxt ||
13985 ((bbr->r_ctl.rc_resend = bbr_check_recovery_mode(tp, bbr, cts)) != NULL))) {
13986 /* Rack cheats and shotguns out all rxt's 1ms apart */
13987 if (slot > 1000)
13988 slot = 1000;
13989 }
13990 if (bbr->bbr_hdrw_pacing && (bbr->hw_pacing_set == 0)) {
13991 /*
13992 * We don't change the tso size until some number of sends
13993 * to give the hardware commands time to get down
13994 * to the interface.
13995 */
13996 bbr->r_ctl.bbr_hdwr_cnt_noset_snt++;
13997 if (bbr->r_ctl.bbr_hdwr_cnt_noset_snt >= bbr_hdwr_pacing_delay_cnt) {
13998 bbr->hw_pacing_set = 1;
13999 tcp_bbr_tso_size_check(bbr, cts);
14000 }
14001 }
14002 bbr_start_hpts_timer(bbr, tp, cts, 12, slot, tot_len);
14003 if (SEQ_LT(tp->snd_nxt, tp->snd_max)) {
14004 /* Make sure snd_nxt is drug up */
14005 tp->snd_nxt = tp->snd_max;
14006 }
14007 return (error);
14008
14009 }
14010
14011 /*
14012 * See bbr_output_wtime() for return values.
14013 */
14014 static int
14015 bbr_output(struct tcpcb *tp)
14016 {
14017 int32_t ret;
14018 struct timeval tv;
14019
14020 NET_EPOCH_ASSERT();
14021
14022 INP_WLOCK_ASSERT(tptoinpcb(tp));
14023 (void)tcp_get_usecs(&tv);
14024 ret = bbr_output_wtime(tp, &tv);
14025 return (ret);
14026 }
14027
14028 static void
14029 bbr_mtu_chg(struct tcpcb *tp)
14030 {
14031 struct tcp_bbr *bbr;
14032 struct bbr_sendmap *rsm, *frsm = NULL;
14033 uint32_t maxseg;
14034
14035 /*
14036 * The MTU has changed. a) Clear the sack filter. b) Mark everything
14037 * over the current size as SACK_PASS so a retransmit will occur.
14038 */
14039
14040 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
14041 maxseg = tp->t_maxseg - bbr->rc_last_options;
14042 sack_filter_clear(&bbr->r_ctl.bbr_sf, tp->snd_una);
14043 TAILQ_FOREACH(rsm, &bbr->r_ctl.rc_map, r_next) {
14044 /* Don't mess with ones acked (by sack?) */
14045 if (rsm->r_flags & BBR_ACKED)
14046 continue;
14047 if ((rsm->r_end - rsm->r_start) > maxseg) {
14048 /*
14049 * We mark sack-passed on all the previous large
14050 * sends we did. This will force them to retransmit.
14051 */
14052 rsm->r_flags |= BBR_SACK_PASSED;
14053 if (((rsm->r_flags & BBR_MARKED_LOST) == 0) &&
14054 bbr_is_lost(bbr, rsm, bbr->r_ctl.rc_rcvtime)) {
14055 bbr->r_ctl.rc_lost_bytes += rsm->r_end - rsm->r_start;
14056 bbr->r_ctl.rc_lost += rsm->r_end - rsm->r_start;
14057 rsm->r_flags |= BBR_MARKED_LOST;
14058 }
14059 if (frsm == NULL)
14060 frsm = rsm;
14061 }
14062 }
14063 if (frsm) {
14064 bbr->r_ctl.rc_resend = frsm;
14065 }
14066 }
14067
14068 static int
14069 bbr_pru_options(struct tcpcb *tp, int flags)
14070 {
14071 if (flags & PRUS_OOB)
14072 return (EOPNOTSUPP);
14073 return (0);
14074 }
14075
14076 struct tcp_function_block __tcp_bbr = {
14077 .tfb_tcp_block_name = __XSTRING(STACKNAME),
14078 .tfb_tcp_output = bbr_output,
14079 .tfb_do_queued_segments = ctf_do_queued_segments,
14080 .tfb_do_segment_nounlock = bbr_do_segment_nounlock,
14081 .tfb_tcp_do_segment = bbr_do_segment,
14082 .tfb_tcp_ctloutput = bbr_ctloutput,
14083 .tfb_tcp_fb_init = bbr_init,
14084 .tfb_tcp_fb_fini = bbr_fini,
14085 .tfb_tcp_timer_stop_all = bbr_stopall,
14086 .tfb_tcp_rexmit_tmr = bbr_remxt_tmr,
14087 .tfb_tcp_handoff_ok = bbr_handoff_ok,
14088 .tfb_tcp_mtu_chg = bbr_mtu_chg,
14089 .tfb_pru_options = bbr_pru_options,
14090 .tfb_flags = TCP_FUNC_OUTPUT_CANDROP,
14091 };
14092
14093 /*
14094 * bbr_ctloutput() must drop the inpcb lock before performing copyin on
14095 * socket option arguments. When it re-acquires the lock after the copy, it
14096 * has to revalidate that the connection is still valid for the socket
14097 * option.
14098 */
14099 static int
14100 bbr_set_sockopt(struct inpcb *inp, struct sockopt *sopt)
14101 {
14102 struct epoch_tracker et;
14103 struct tcpcb *tp;
14104 struct tcp_bbr *bbr;
14105 int32_t error = 0, optval;
14106
14107 switch (sopt->sopt_level) {
14108 case IPPROTO_IPV6:
14109 case IPPROTO_IP:
14110 return (tcp_default_ctloutput(inp, sopt));
14111 }
14112
14113 switch (sopt->sopt_name) {
14114 case TCP_RACK_PACE_MAX_SEG:
14115 case TCP_RACK_MIN_TO:
14116 case TCP_RACK_REORD_THRESH:
14117 case TCP_RACK_REORD_FADE:
14118 case TCP_RACK_TLP_THRESH:
14119 case TCP_RACK_PKT_DELAY:
14120 case TCP_BBR_ALGORITHM:
14121 case TCP_BBR_TSLIMITS:
14122 case TCP_BBR_IWINTSO:
14123 case TCP_BBR_RECFORCE:
14124 case TCP_BBR_STARTUP_PG:
14125 case TCP_BBR_DRAIN_PG:
14126 case TCP_BBR_RWND_IS_APP:
14127 case TCP_BBR_PROBE_RTT_INT:
14128 case TCP_BBR_PROBE_RTT_GAIN:
14129 case TCP_BBR_PROBE_RTT_LEN:
14130 case TCP_BBR_STARTUP_LOSS_EXIT:
14131 case TCP_BBR_USEDEL_RATE:
14132 case TCP_BBR_MIN_RTO:
14133 case TCP_BBR_MAX_RTO:
14134 case TCP_BBR_PACE_PER_SEC:
14135 case TCP_DELACK:
14136 case TCP_BBR_PACE_DEL_TAR:
14137 case TCP_BBR_SEND_IWND_IN_TSO:
14138 case TCP_BBR_EXTRA_STATE:
14139 case TCP_BBR_UTTER_MAX_TSO:
14140 case TCP_BBR_MIN_TOPACEOUT:
14141 case TCP_BBR_FLOOR_MIN_TSO:
14142 case TCP_BBR_TSTMP_RAISES:
14143 case TCP_BBR_POLICER_DETECT:
14144 case TCP_BBR_USE_RACK_CHEAT:
14145 case TCP_DATA_AFTER_CLOSE:
14146 case TCP_BBR_HDWR_PACE:
14147 case TCP_BBR_PACE_SEG_MAX:
14148 case TCP_BBR_PACE_SEG_MIN:
14149 case TCP_BBR_PACE_CROSS:
14150 case TCP_BBR_PACE_OH:
14151 #ifdef NETFLIX_PEAKRATE
14152 case TCP_MAXPEAKRATE:
14153 #endif
14154 case TCP_BBR_TMR_PACE_OH:
14155 case TCP_BBR_RACK_RTT_USE:
14156 case TCP_BBR_RETRAN_WTSO:
14157 break;
14158 default:
14159 return (tcp_default_ctloutput(inp, sopt));
14160 break;
14161 }
14162 INP_WUNLOCK(inp);
14163 error = sooptcopyin(sopt, &optval, sizeof(optval), sizeof(optval));
14164 if (error)
14165 return (error);
14166 INP_WLOCK(inp);
14167 if (inp->inp_flags & INP_DROPPED) {
14168 INP_WUNLOCK(inp);
14169 return (ECONNRESET);
14170 }
14171 tp = intotcpcb(inp);
14172 if (tp->t_fb != &__tcp_bbr) {
14173 INP_WUNLOCK(inp);
14174 return (ENOPROTOOPT);
14175 }
14176 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
14177 switch (sopt->sopt_name) {
14178 case TCP_BBR_PACE_PER_SEC:
14179 BBR_OPTS_INC(tcp_bbr_pace_per_sec);
14180 bbr->r_ctl.bbr_hptsi_per_second = optval;
14181 break;
14182 case TCP_BBR_PACE_DEL_TAR:
14183 BBR_OPTS_INC(tcp_bbr_pace_del_tar);
14184 bbr->r_ctl.bbr_hptsi_segments_delay_tar = optval;
14185 break;
14186 case TCP_BBR_PACE_SEG_MAX:
14187 BBR_OPTS_INC(tcp_bbr_pace_seg_max);
14188 bbr->r_ctl.bbr_hptsi_segments_max = optval;
14189 break;
14190 case TCP_BBR_PACE_SEG_MIN:
14191 BBR_OPTS_INC(tcp_bbr_pace_seg_min);
14192 bbr->r_ctl.bbr_hptsi_bytes_min = optval;
14193 break;
14194 case TCP_BBR_PACE_CROSS:
14195 BBR_OPTS_INC(tcp_bbr_pace_cross);
14196 bbr->r_ctl.bbr_cross_over = optval;
14197 break;
14198 case TCP_BBR_ALGORITHM:
14199 BBR_OPTS_INC(tcp_bbr_algorithm);
14200 if (optval && (bbr->rc_use_google == 0)) {
14201 /* Turn on the google mode */
14202 bbr_google_mode_on(bbr);
14203 if ((optval > 3) && (optval < 500)) {
14204 /*
14205 * Must be at least greater than .3%
14206 * and must be less than 50.0%.
14207 */
14208 bbr->r_ctl.bbr_google_discount = optval;
14209 }
14210 } else if ((optval == 0) && (bbr->rc_use_google == 1)) {
14211 /* Turn off the google mode */
14212 bbr_google_mode_off(bbr);
14213 }
14214 break;
14215 case TCP_BBR_TSLIMITS:
14216 BBR_OPTS_INC(tcp_bbr_tslimits);
14217 if (optval == 1)
14218 bbr->rc_use_ts_limit = 1;
14219 else if (optval == 0)
14220 bbr->rc_use_ts_limit = 0;
14221 else
14222 error = EINVAL;
14223 break;
14224
14225 case TCP_BBR_IWINTSO:
14226 BBR_OPTS_INC(tcp_bbr_iwintso);
14227 if ((optval >= 0) && (optval < 128)) {
14228 uint32_t twin;
14229
14230 bbr->rc_init_win = optval;
14231 twin = bbr_initial_cwnd(bbr, tp);
14232 if ((bbr->rc_past_init_win == 0) && (twin > tp->snd_cwnd))
14233 tp->snd_cwnd = twin;
14234 else
14235 error = EBUSY;
14236 } else
14237 error = EINVAL;
14238 break;
14239 case TCP_BBR_STARTUP_PG:
14240 BBR_OPTS_INC(tcp_bbr_startup_pg);
14241 if ((optval > 0) && (optval < BBR_MAX_GAIN_VALUE)) {
14242 bbr->r_ctl.rc_startup_pg = optval;
14243 if (bbr->rc_bbr_state == BBR_STATE_STARTUP) {
14244 bbr->r_ctl.rc_bbr_hptsi_gain = optval;
14245 }
14246 } else
14247 error = EINVAL;
14248 break;
14249 case TCP_BBR_DRAIN_PG:
14250 BBR_OPTS_INC(tcp_bbr_drain_pg);
14251 if ((optval > 0) && (optval < BBR_MAX_GAIN_VALUE))
14252 bbr->r_ctl.rc_drain_pg = optval;
14253 else
14254 error = EINVAL;
14255 break;
14256 case TCP_BBR_PROBE_RTT_LEN:
14257 BBR_OPTS_INC(tcp_bbr_probertt_len);
14258 if (optval <= 1)
14259 reset_time_small(&bbr->r_ctl.rc_rttprop, (optval * USECS_IN_SECOND));
14260 else
14261 error = EINVAL;
14262 break;
14263 case TCP_BBR_PROBE_RTT_GAIN:
14264 BBR_OPTS_INC(tcp_bbr_probertt_gain);
14265 if (optval <= BBR_UNIT)
14266 bbr->r_ctl.bbr_rttprobe_gain_val = optval;
14267 else
14268 error = EINVAL;
14269 break;
14270 case TCP_BBR_PROBE_RTT_INT:
14271 BBR_OPTS_INC(tcp_bbr_probe_rtt_int);
14272 if (optval > 1000)
14273 bbr->r_ctl.rc_probertt_int = optval;
14274 else
14275 error = EINVAL;
14276 break;
14277 case TCP_BBR_MIN_TOPACEOUT:
14278 BBR_OPTS_INC(tcp_bbr_topaceout);
14279 if (optval == 0) {
14280 bbr->no_pacing_until = 0;
14281 bbr->rc_no_pacing = 0;
14282 } else if (optval <= 0x00ff) {
14283 bbr->no_pacing_until = optval;
14284 if ((bbr->r_ctl.rc_pkt_epoch < bbr->no_pacing_until) &&
14285 (bbr->rc_bbr_state == BBR_STATE_STARTUP)){
14286 /* Turn on no pacing */
14287 bbr->rc_no_pacing = 1;
14288 }
14289 } else
14290 error = EINVAL;
14291 break;
14292 case TCP_BBR_STARTUP_LOSS_EXIT:
14293 BBR_OPTS_INC(tcp_bbr_startup_loss_exit);
14294 bbr->rc_loss_exit = optval;
14295 break;
14296 case TCP_BBR_USEDEL_RATE:
14297 error = EINVAL;
14298 break;
14299 case TCP_BBR_MIN_RTO:
14300 BBR_OPTS_INC(tcp_bbr_min_rto);
14301 bbr->r_ctl.rc_min_rto_ms = optval;
14302 break;
14303 case TCP_BBR_MAX_RTO:
14304 BBR_OPTS_INC(tcp_bbr_max_rto);
14305 bbr->rc_max_rto_sec = optval;
14306 break;
14307 case TCP_RACK_MIN_TO:
14308 /* Minimum time between rack t-o's in ms */
14309 BBR_OPTS_INC(tcp_rack_min_to);
14310 bbr->r_ctl.rc_min_to = optval;
14311 break;
14312 case TCP_RACK_REORD_THRESH:
14313 /* RACK reorder threshold (shift amount) */
14314 BBR_OPTS_INC(tcp_rack_reord_thresh);
14315 if ((optval > 0) && (optval < 31))
14316 bbr->r_ctl.rc_reorder_shift = optval;
14317 else
14318 error = EINVAL;
14319 break;
14320 case TCP_RACK_REORD_FADE:
14321 /* Does reordering fade after ms time */
14322 BBR_OPTS_INC(tcp_rack_reord_fade);
14323 bbr->r_ctl.rc_reorder_fade = optval;
14324 break;
14325 case TCP_RACK_TLP_THRESH:
14326 /* RACK TLP theshold i.e. srtt+(srtt/N) */
14327 BBR_OPTS_INC(tcp_rack_tlp_thresh);
14328 if (optval)
14329 bbr->rc_tlp_threshold = optval;
14330 else
14331 error = EINVAL;
14332 break;
14333 case TCP_BBR_USE_RACK_CHEAT:
14334 BBR_OPTS_INC(tcp_use_rackcheat);
14335 if (bbr->rc_use_google) {
14336 error = EINVAL;
14337 break;
14338 }
14339 BBR_OPTS_INC(tcp_rack_cheat);
14340 if (optval)
14341 bbr->bbr_use_rack_cheat = 1;
14342 else
14343 bbr->bbr_use_rack_cheat = 0;
14344 break;
14345 case TCP_BBR_FLOOR_MIN_TSO:
14346 BBR_OPTS_INC(tcp_utter_max_tso);
14347 if ((optval >= 0) && (optval < 40))
14348 bbr->r_ctl.bbr_hptsi_segments_floor = optval;
14349 else
14350 error = EINVAL;
14351 break;
14352 case TCP_BBR_UTTER_MAX_TSO:
14353 BBR_OPTS_INC(tcp_utter_max_tso);
14354 if ((optval >= 0) && (optval < 0xffff))
14355 bbr->r_ctl.bbr_utter_max = optval;
14356 else
14357 error = EINVAL;
14358 break;
14359
14360 case TCP_BBR_EXTRA_STATE:
14361 BBR_OPTS_INC(tcp_extra_state);
14362 if (optval)
14363 bbr->rc_use_idle_restart = 1;
14364 else
14365 bbr->rc_use_idle_restart = 0;
14366 break;
14367 case TCP_BBR_SEND_IWND_IN_TSO:
14368 BBR_OPTS_INC(tcp_iwnd_tso);
14369 if (optval) {
14370 bbr->bbr_init_win_cheat = 1;
14371 if (bbr->rc_past_init_win == 0) {
14372 uint32_t cts;
14373 cts = tcp_get_usecs(&bbr->rc_tv);
14374 tcp_bbr_tso_size_check(bbr, cts);
14375 }
14376 } else
14377 bbr->bbr_init_win_cheat = 0;
14378 break;
14379 case TCP_BBR_HDWR_PACE:
14380 BBR_OPTS_INC(tcp_hdwr_pacing);
14381 if (optval){
14382 bbr->bbr_hdw_pace_ena = 1;
14383 bbr->bbr_attempt_hdwr_pace = 0;
14384 } else {
14385 bbr->bbr_hdw_pace_ena = 0;
14386 #ifdef RATELIMIT
14387 if (bbr->r_ctl.crte != NULL) {
14388 tcp_rel_pacing_rate(bbr->r_ctl.crte, tp);
14389 bbr->r_ctl.crte = NULL;
14390 }
14391 #endif
14392 }
14393 break;
14394
14395 case TCP_DELACK:
14396 BBR_OPTS_INC(tcp_delack);
14397 if (optval < 100) {
14398 if (optval == 0) /* off */
14399 tp->t_delayed_ack = 0;
14400 else if (optval == 1) /* on which is 2 */
14401 tp->t_delayed_ack = 2;
14402 else /* higher than 2 and less than 100 */
14403 tp->t_delayed_ack = optval;
14404 if (tp->t_flags & TF_DELACK) {
14405 tp->t_flags &= ~TF_DELACK;
14406 tp->t_flags |= TF_ACKNOW;
14407 NET_EPOCH_ENTER(et);
14408 bbr_output(tp);
14409 NET_EPOCH_EXIT(et);
14410 }
14411 } else
14412 error = EINVAL;
14413 break;
14414 case TCP_RACK_PKT_DELAY:
14415 /* RACK added ms i.e. rack-rtt + reord + N */
14416 BBR_OPTS_INC(tcp_rack_pkt_delay);
14417 bbr->r_ctl.rc_pkt_delay = optval;
14418 break;
14419 #ifdef NETFLIX_PEAKRATE
14420 case TCP_MAXPEAKRATE:
14421 BBR_OPTS_INC(tcp_maxpeak);
14422 error = tcp_set_maxpeakrate(tp, optval);
14423 if (!error)
14424 tp->t_peakrate_thr = tp->t_maxpeakrate;
14425 break;
14426 #endif
14427 case TCP_BBR_RETRAN_WTSO:
14428 BBR_OPTS_INC(tcp_retran_wtso);
14429 if (optval)
14430 bbr->rc_resends_use_tso = 1;
14431 else
14432 bbr->rc_resends_use_tso = 0;
14433 break;
14434 case TCP_DATA_AFTER_CLOSE:
14435 BBR_OPTS_INC(tcp_data_ac);
14436 if (optval)
14437 bbr->rc_allow_data_af_clo = 1;
14438 else
14439 bbr->rc_allow_data_af_clo = 0;
14440 break;
14441 case TCP_BBR_POLICER_DETECT:
14442 BBR_OPTS_INC(tcp_policer_det);
14443 if (bbr->rc_use_google == 0)
14444 error = EINVAL;
14445 else if (optval)
14446 bbr->r_use_policer = 1;
14447 else
14448 bbr->r_use_policer = 0;
14449 break;
14450
14451 case TCP_BBR_TSTMP_RAISES:
14452 BBR_OPTS_INC(tcp_ts_raises);
14453 if (optval)
14454 bbr->ts_can_raise = 1;
14455 else
14456 bbr->ts_can_raise = 0;
14457 break;
14458 case TCP_BBR_TMR_PACE_OH:
14459 BBR_OPTS_INC(tcp_pacing_oh_tmr);
14460 if (bbr->rc_use_google) {
14461 error = EINVAL;
14462 } else {
14463 if (optval)
14464 bbr->r_ctl.rc_incr_tmrs = 1;
14465 else
14466 bbr->r_ctl.rc_incr_tmrs = 0;
14467 }
14468 break;
14469 case TCP_BBR_PACE_OH:
14470 BBR_OPTS_INC(tcp_pacing_oh);
14471 if (bbr->rc_use_google) {
14472 error = EINVAL;
14473 } else {
14474 if (optval > (BBR_INCL_TCP_OH|
14475 BBR_INCL_IP_OH|
14476 BBR_INCL_ENET_OH)) {
14477 error = EINVAL;
14478 break;
14479 }
14480 if (optval & BBR_INCL_TCP_OH)
14481 bbr->r_ctl.rc_inc_tcp_oh = 1;
14482 else
14483 bbr->r_ctl.rc_inc_tcp_oh = 0;
14484 if (optval & BBR_INCL_IP_OH)
14485 bbr->r_ctl.rc_inc_ip_oh = 1;
14486 else
14487 bbr->r_ctl.rc_inc_ip_oh = 0;
14488 if (optval & BBR_INCL_ENET_OH)
14489 bbr->r_ctl.rc_inc_enet_oh = 1;
14490 else
14491 bbr->r_ctl.rc_inc_enet_oh = 0;
14492 }
14493 break;
14494 default:
14495 return (tcp_default_ctloutput(inp, sopt));
14496 break;
14497 }
14498 #ifdef NETFLIX_STATS
14499 tcp_log_socket_option(tp, sopt->sopt_name, optval, error);
14500 #endif
14501 INP_WUNLOCK(inp);
14502 return (error);
14503 }
14504
14505 /*
14506 * return 0 on success, error-num on failure
14507 */
14508 static int
14509 bbr_get_sockopt(struct inpcb *inp, struct sockopt *sopt)
14510 {
14511 struct tcpcb *tp;
14512 struct tcp_bbr *bbr;
14513 int32_t error, optval;
14514
14515 tp = intotcpcb(inp);
14516 bbr = (struct tcp_bbr *)tp->t_fb_ptr;
14517 if (bbr == NULL) {
14518 INP_WUNLOCK(inp);
14519 return (EINVAL);
14520 }
14521 /*
14522 * Because all our options are either boolean or an int, we can just
14523 * pull everything into optval and then unlock and copy. If we ever
14524 * add a option that is not a int, then this will have quite an
14525 * impact to this routine.
14526 */
14527 switch (sopt->sopt_name) {
14528 case TCP_BBR_PACE_PER_SEC:
14529 optval = bbr->r_ctl.bbr_hptsi_per_second;
14530 break;
14531 case TCP_BBR_PACE_DEL_TAR:
14532 optval = bbr->r_ctl.bbr_hptsi_segments_delay_tar;
14533 break;
14534 case TCP_BBR_PACE_SEG_MAX:
14535 optval = bbr->r_ctl.bbr_hptsi_segments_max;
14536 break;
14537 case TCP_BBR_MIN_TOPACEOUT:
14538 optval = bbr->no_pacing_until;
14539 break;
14540 case TCP_BBR_PACE_SEG_MIN:
14541 optval = bbr->r_ctl.bbr_hptsi_bytes_min;
14542 break;
14543 case TCP_BBR_PACE_CROSS:
14544 optval = bbr->r_ctl.bbr_cross_over;
14545 break;
14546 case TCP_BBR_ALGORITHM:
14547 optval = bbr->rc_use_google;
14548 break;
14549 case TCP_BBR_TSLIMITS:
14550 optval = bbr->rc_use_ts_limit;
14551 break;
14552 case TCP_BBR_IWINTSO:
14553 optval = bbr->rc_init_win;
14554 break;
14555 case TCP_BBR_STARTUP_PG:
14556 optval = bbr->r_ctl.rc_startup_pg;
14557 break;
14558 case TCP_BBR_DRAIN_PG:
14559 optval = bbr->r_ctl.rc_drain_pg;
14560 break;
14561 case TCP_BBR_PROBE_RTT_INT:
14562 optval = bbr->r_ctl.rc_probertt_int;
14563 break;
14564 case TCP_BBR_PROBE_RTT_LEN:
14565 optval = (bbr->r_ctl.rc_rttprop.cur_time_limit / USECS_IN_SECOND);
14566 break;
14567 case TCP_BBR_PROBE_RTT_GAIN:
14568 optval = bbr->r_ctl.bbr_rttprobe_gain_val;
14569 break;
14570 case TCP_BBR_STARTUP_LOSS_EXIT:
14571 optval = bbr->rc_loss_exit;
14572 break;
14573 case TCP_BBR_USEDEL_RATE:
14574 error = EINVAL;
14575 break;
14576 case TCP_BBR_MIN_RTO:
14577 optval = bbr->r_ctl.rc_min_rto_ms;
14578 break;
14579 case TCP_BBR_MAX_RTO:
14580 optval = bbr->rc_max_rto_sec;
14581 break;
14582 case TCP_RACK_PACE_MAX_SEG:
14583 /* Max segments in a pace */
14584 optval = bbr->r_ctl.rc_pace_max_segs;
14585 break;
14586 case TCP_RACK_MIN_TO:
14587 /* Minimum time between rack t-o's in ms */
14588 optval = bbr->r_ctl.rc_min_to;
14589 break;
14590 case TCP_RACK_REORD_THRESH:
14591 /* RACK reorder threshold (shift amount) */
14592 optval = bbr->r_ctl.rc_reorder_shift;
14593 break;
14594 case TCP_RACK_REORD_FADE:
14595 /* Does reordering fade after ms time */
14596 optval = bbr->r_ctl.rc_reorder_fade;
14597 break;
14598 case TCP_BBR_USE_RACK_CHEAT:
14599 /* Do we use the rack cheat for rxt */
14600 optval = bbr->bbr_use_rack_cheat;
14601 break;
14602 case TCP_BBR_FLOOR_MIN_TSO:
14603 optval = bbr->r_ctl.bbr_hptsi_segments_floor;
14604 break;
14605 case TCP_BBR_UTTER_MAX_TSO:
14606 optval = bbr->r_ctl.bbr_utter_max;
14607 break;
14608 case TCP_BBR_SEND_IWND_IN_TSO:
14609 /* Do we send TSO size segments initially */
14610 optval = bbr->bbr_init_win_cheat;
14611 break;
14612 case TCP_BBR_EXTRA_STATE:
14613 optval = bbr->rc_use_idle_restart;
14614 break;
14615 case TCP_RACK_TLP_THRESH:
14616 /* RACK TLP theshold i.e. srtt+(srtt/N) */
14617 optval = bbr->rc_tlp_threshold;
14618 break;
14619 case TCP_RACK_PKT_DELAY:
14620 /* RACK added ms i.e. rack-rtt + reord + N */
14621 optval = bbr->r_ctl.rc_pkt_delay;
14622 break;
14623 case TCP_BBR_RETRAN_WTSO:
14624 optval = bbr->rc_resends_use_tso;
14625 break;
14626 case TCP_DATA_AFTER_CLOSE:
14627 optval = bbr->rc_allow_data_af_clo;
14628 break;
14629 case TCP_DELACK:
14630 optval = tp->t_delayed_ack;
14631 break;
14632 case TCP_BBR_HDWR_PACE:
14633 optval = bbr->bbr_hdw_pace_ena;
14634 break;
14635 case TCP_BBR_POLICER_DETECT:
14636 optval = bbr->r_use_policer;
14637 break;
14638 case TCP_BBR_TSTMP_RAISES:
14639 optval = bbr->ts_can_raise;
14640 break;
14641 case TCP_BBR_TMR_PACE_OH:
14642 optval = bbr->r_ctl.rc_incr_tmrs;
14643 break;
14644 case TCP_BBR_PACE_OH:
14645 optval = 0;
14646 if (bbr->r_ctl.rc_inc_tcp_oh)
14647 optval |= BBR_INCL_TCP_OH;
14648 if (bbr->r_ctl.rc_inc_ip_oh)
14649 optval |= BBR_INCL_IP_OH;
14650 if (bbr->r_ctl.rc_inc_enet_oh)
14651 optval |= BBR_INCL_ENET_OH;
14652 break;
14653 default:
14654 return (tcp_default_ctloutput(inp, sopt));
14655 break;
14656 }
14657 INP_WUNLOCK(inp);
14658 error = sooptcopyout(sopt, &optval, sizeof optval);
14659 return (error);
14660 }
14661
14662 /*
14663 * return 0 on success, error-num on failure
14664 */
14665 static int
14666 bbr_ctloutput(struct inpcb *inp, struct sockopt *sopt)
14667 {
14668 if (sopt->sopt_dir == SOPT_SET) {
14669 return (bbr_set_sockopt(inp, sopt));
14670 } else if (sopt->sopt_dir == SOPT_GET) {
14671 return (bbr_get_sockopt(inp, sopt));
14672 } else {
14673 panic("%s: sopt_dir $%d", __func__, sopt->sopt_dir);
14674 }
14675 }
14676
14677 static const char *bbr_stack_names[] = {
14678 __XSTRING(STACKNAME),
14679 #ifdef STACKALIAS
14680 __XSTRING(STACKALIAS),
14681 #endif
14682 };
14683
14684 static bool bbr_mod_inited = false;
14685
14686 static int
14687 tcp_addbbr(module_t mod, int32_t type, void *data)
14688 {
14689 int32_t err = 0;
14690 int num_stacks;
14691
14692 switch (type) {
14693 case MOD_LOAD:
14694 printf("Attempting to load " __XSTRING(MODNAME) "\n");
14695 bbr_zone = uma_zcreate(__XSTRING(MODNAME) "_map",
14696 sizeof(struct bbr_sendmap),
14697 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
14698 bbr_pcb_zone = uma_zcreate(__XSTRING(MODNAME) "_pcb",
14699 sizeof(struct tcp_bbr),
14700 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
14701 sysctl_ctx_init(&bbr_sysctl_ctx);
14702 bbr_sysctl_root = SYSCTL_ADD_NODE(&bbr_sysctl_ctx,
14703 SYSCTL_STATIC_CHILDREN(_net_inet_tcp),
14704 OID_AUTO,
14705 #ifdef STACKALIAS
14706 __XSTRING(STACKALIAS),
14707 #else
14708 __XSTRING(STACKNAME),
14709 #endif
14710 CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
14711 "");
14712 if (bbr_sysctl_root == NULL) {
14713 printf("Failed to add sysctl node\n");
14714 err = EFAULT;
14715 goto free_uma;
14716 }
14717 bbr_init_sysctls();
14718 num_stacks = nitems(bbr_stack_names);
14719 err = register_tcp_functions_as_names(&__tcp_bbr, M_WAITOK,
14720 bbr_stack_names, &num_stacks);
14721 if (err) {
14722 printf("Failed to register %s stack name for "
14723 "%s module\n", bbr_stack_names[num_stacks],
14724 __XSTRING(MODNAME));
14725 sysctl_ctx_free(&bbr_sysctl_ctx);
14726 free_uma:
14727 uma_zdestroy(bbr_zone);
14728 uma_zdestroy(bbr_pcb_zone);
14729 bbr_counter_destroy();
14730 printf("Failed to register " __XSTRING(MODNAME)
14731 " module err:%d\n", err);
14732 return (err);
14733 }
14734 tcp_lro_reg_mbufq();
14735 bbr_mod_inited = true;
14736 printf(__XSTRING(MODNAME) " is now available\n");
14737 break;
14738 case MOD_QUIESCE:
14739 err = deregister_tcp_functions(&__tcp_bbr, true, false);
14740 break;
14741 case MOD_UNLOAD:
14742 err = deregister_tcp_functions(&__tcp_bbr, false, true);
14743 if (err == EBUSY)
14744 break;
14745 if (bbr_mod_inited) {
14746 uma_zdestroy(bbr_zone);
14747 uma_zdestroy(bbr_pcb_zone);
14748 sysctl_ctx_free(&bbr_sysctl_ctx);
14749 bbr_counter_destroy();
14750 printf(__XSTRING(MODNAME)
14751 " is now no longer available\n");
14752 bbr_mod_inited = false;
14753 }
14754 tcp_lro_dereg_mbufq();
14755 err = 0;
14756 break;
14757 default:
14758 return (EOPNOTSUPP);
14759 }
14760 return (err);
14761 }
14762
14763 static moduledata_t tcp_bbr = {
14764 .name = __XSTRING(MODNAME),
14765 .evhand = tcp_addbbr,
14766 .priv = 0
14767 };
14768
14769 MODULE_VERSION(MODNAME, 1);
14770 DECLARE_MODULE(MODNAME, tcp_bbr, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY);
14771 MODULE_DEPEND(MODNAME, tcphpts, 1, 1, 1);
Cache object: 8d22a9dbe8ab809114514fe7c548a7bf
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