1 /*-
2 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
3 * Copyright (c) 2008-2011, by Randall Stewart. All rights reserved.
4 * Copyright (c) 2008-2011, by Michael Tuexen. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * a) Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
11 *
12 * b) Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in
14 * the documentation and/or other materials provided with the distribution.
15 *
16 * c) Neither the name of Cisco Systems, Inc. nor the names of its
17 * contributors may be used to endorse or promote products derived
18 * from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
22 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
30 * THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include <netinet/sctp_os.h>
34 #include <netinet/sctp_var.h>
35 #include <netinet/sctp_sysctl.h>
36 #include <netinet/sctp_pcb.h>
37 #include <netinet/sctp_header.h>
38 #include <netinet/sctputil.h>
39 #include <netinet/sctp_output.h>
40 #include <netinet/sctp_input.h>
41 #include <netinet/sctp_indata.h>
42 #include <netinet/sctp_uio.h>
43 #include <netinet/sctp_timer.h>
44 #include <netinet/sctp_auth.h>
45 #include <netinet/sctp_asconf.h>
46 #include <netinet/sctp_dtrace_declare.h>
47 #include <sys/cdefs.h>
48 __FBSDID("$FreeBSD: releng/8.3/sys/netinet/sctp_cc_functions.c 231492 2012-02-11 00:57:08Z tuexen $");
49
50 #define SHIFT_MPTCP_MULTI_N 40
51 #define SHIFT_MPTCP_MULTI_Z 16
52 #define SHIFT_MPTCP_MULTI 8
53
54 static void
55 sctp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net)
56 {
57 struct sctp_association *assoc;
58 uint32_t cwnd_in_mtu;
59
60 assoc = &stcb->asoc;
61 cwnd_in_mtu = SCTP_BASE_SYSCTL(sctp_initial_cwnd);
62 if (cwnd_in_mtu == 0) {
63 /* Using 0 means that the value of RFC 4960 is used. */
64 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
65 } else {
66 /*
67 * We take the minimum of the burst limit and the initial
68 * congestion window.
69 */
70 if ((assoc->max_burst > 0) && (cwnd_in_mtu > assoc->max_burst))
71 cwnd_in_mtu = assoc->max_burst;
72 net->cwnd = (net->mtu - sizeof(struct sctphdr)) * cwnd_in_mtu;
73 }
74 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) ||
75 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2)) {
76 /* In case of resource pooling initialize appropriately */
77 net->cwnd /= assoc->numnets;
78 if (net->cwnd < (net->mtu - sizeof(struct sctphdr))) {
79 net->cwnd = net->mtu - sizeof(struct sctphdr);
80 }
81 }
82 net->ssthresh = assoc->peers_rwnd;
83 SDT_PROBE(sctp, cwnd, net, init,
84 stcb->asoc.my_vtag, ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), net,
85 0, net->cwnd);
86 if (SCTP_BASE_SYSCTL(sctp_logging_level) &
87 (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) {
88 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION);
89 }
90 }
91
92 static void
93 sctp_cwnd_update_after_fr(struct sctp_tcb *stcb,
94 struct sctp_association *asoc)
95 {
96 struct sctp_nets *net;
97 uint32_t t_ssthresh, t_cwnd;
98 uint64_t t_ucwnd_sbw;
99
100 /* MT FIXME: Don't compute this over and over again */
101 t_ssthresh = 0;
102 t_cwnd = 0;
103 t_ucwnd_sbw = 0;
104 if ((asoc->sctp_cmt_on_off == SCTP_CMT_RPV1) ||
105 (asoc->sctp_cmt_on_off == SCTP_CMT_RPV2)) {
106 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
107 t_ssthresh += net->ssthresh;
108 t_cwnd += net->cwnd;
109 if (net->lastsa > 0) {
110 t_ucwnd_sbw += (uint64_t) net->cwnd / (uint64_t) net->lastsa;
111 }
112 }
113 if (t_ucwnd_sbw == 0) {
114 t_ucwnd_sbw = 1;
115 }
116 }
117 /*-
118 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) &&
119 * (net->fast_retran_loss_recovery == 0)))
120 */
121 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
122 if ((asoc->fast_retran_loss_recovery == 0) ||
123 (asoc->sctp_cmt_on_off > 0)) {
124 /* out of a RFC2582 Fast recovery window? */
125 if (net->net_ack > 0) {
126 /*
127 * per section 7.2.3, are there any
128 * destinations that had a fast retransmit
129 * to them. If so what we need to do is
130 * adjust ssthresh and cwnd.
131 */
132 struct sctp_tmit_chunk *lchk;
133 int old_cwnd = net->cwnd;
134
135 if ((asoc->sctp_cmt_on_off == SCTP_CMT_RPV1) ||
136 (asoc->sctp_cmt_on_off == SCTP_CMT_RPV2)) {
137 if (asoc->sctp_cmt_on_off == SCTP_CMT_RPV1) {
138 net->ssthresh = (uint32_t) (((uint64_t) 4 *
139 (uint64_t) net->mtu *
140 (uint64_t) net->ssthresh) /
141 (uint64_t) t_ssthresh);
142
143 }
144 if (asoc->sctp_cmt_on_off == SCTP_CMT_RPV2) {
145 uint32_t srtt;
146
147 srtt = net->lastsa;
148 /*
149 * lastsa>>3; we don't need
150 * to devide ...
151 */
152 if (srtt == 0) {
153 srtt = 1;
154 }
155 /*
156 * Short Version => Equal to
157 * Contel Version MBe
158 */
159 net->ssthresh = (uint32_t) (((uint64_t) 4 *
160 (uint64_t) net->mtu *
161 (uint64_t) net->cwnd) /
162 ((uint64_t) srtt *
163 t_ucwnd_sbw));
164 /* INCREASE FACTOR */ ;
165 }
166 if ((net->cwnd > t_cwnd / 2) &&
167 (net->ssthresh < net->cwnd - t_cwnd / 2)) {
168 net->ssthresh = net->cwnd - t_cwnd / 2;
169 }
170 if (net->ssthresh < net->mtu) {
171 net->ssthresh = net->mtu;
172 }
173 } else {
174 net->ssthresh = net->cwnd / 2;
175 if (net->ssthresh < (net->mtu * 2)) {
176 net->ssthresh = 2 * net->mtu;
177 }
178 }
179 net->cwnd = net->ssthresh;
180 SDT_PROBE(sctp, cwnd, net, fr,
181 stcb->asoc.my_vtag, ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), net,
182 old_cwnd, net->cwnd);
183 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
184 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
185 SCTP_CWND_LOG_FROM_FR);
186 }
187 lchk = TAILQ_FIRST(&asoc->send_queue);
188
189 net->partial_bytes_acked = 0;
190 /* Turn on fast recovery window */
191 asoc->fast_retran_loss_recovery = 1;
192 if (lchk == NULL) {
193 /* Mark end of the window */
194 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
195 } else {
196 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
197 }
198
199 /*
200 * CMT fast recovery -- per destination
201 * recovery variable.
202 */
203 net->fast_retran_loss_recovery = 1;
204
205 if (lchk == NULL) {
206 /* Mark end of the window */
207 net->fast_recovery_tsn = asoc->sending_seq - 1;
208 } else {
209 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
210 }
211
212 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
213 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
214 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
215 stcb->sctp_ep, stcb, net);
216 }
217 } else if (net->net_ack > 0) {
218 /*
219 * Mark a peg that we WOULD have done a cwnd
220 * reduction but RFC2582 prevented this action.
221 */
222 SCTP_STAT_INCR(sctps_fastretransinrtt);
223 }
224 }
225 }
226
227 /* Defines for instantaneous bw decisions */
228 #define SCTP_INST_LOOSING 1 /* Loosing to other flows */
229 #define SCTP_INST_NEUTRAL 2 /* Neutral, no indication */
230 #define SCTP_INST_GAINING 3 /* Gaining, step down possible */
231
232
233 static int
234 cc_bw_same(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw,
235 uint64_t rtt_offset, uint64_t vtag, uint8_t inst_ind)
236 {
237 uint64_t oth, probepoint;
238
239 probepoint = (((uint64_t) net->cwnd) << 32);
240 if (net->rtt > net->cc_mod.rtcc.lbw_rtt + rtt_offset) {
241 /*
242 * rtt increased we don't update bw.. so we don't update the
243 * rtt either.
244 */
245 /* Probe point 5 */
246 probepoint |= ((5 << 16) | 1);
247 SDT_PROBE(sctp, cwnd, net, rttvar,
248 vtag,
249 ((net->cc_mod.rtcc.lbw << 32) | nbw),
250 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
251 net->flight_size,
252 probepoint);
253 if ((net->cc_mod.rtcc.steady_step) && (inst_ind != SCTP_INST_LOOSING)) {
254 if (net->cc_mod.rtcc.last_step_state == 5)
255 net->cc_mod.rtcc.step_cnt++;
256 else
257 net->cc_mod.rtcc.step_cnt = 1;
258 net->cc_mod.rtcc.last_step_state = 5;
259 if ((net->cc_mod.rtcc.step_cnt == net->cc_mod.rtcc.steady_step) ||
260 ((net->cc_mod.rtcc.step_cnt > net->cc_mod.rtcc.steady_step) &&
261 ((net->cc_mod.rtcc.step_cnt % net->cc_mod.rtcc.steady_step) == 0))) {
262 /* Try a step down */
263 oth = net->cc_mod.rtcc.vol_reduce;
264 oth <<= 16;
265 oth |= net->cc_mod.rtcc.step_cnt;
266 oth <<= 16;
267 oth |= net->cc_mod.rtcc.last_step_state;
268 SDT_PROBE(sctp, cwnd, net, rttstep,
269 vtag,
270 ((net->cc_mod.rtcc.lbw << 32) | nbw),
271 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
272 oth,
273 probepoint);
274 if (net->cwnd > (4 * net->mtu)) {
275 net->cwnd -= net->mtu;
276 net->cc_mod.rtcc.vol_reduce++;
277 } else {
278 net->cc_mod.rtcc.step_cnt = 0;
279 }
280 }
281 }
282 return (1);
283 }
284 if (net->rtt < net->cc_mod.rtcc.lbw_rtt - rtt_offset) {
285 /*
286 * rtt decreased, there could be more room. we update both
287 * the bw and the rtt here to lock this in as a good step
288 * down.
289 */
290 /* Probe point 6 */
291 probepoint |= ((6 << 16) | 0);
292 SDT_PROBE(sctp, cwnd, net, rttvar,
293 vtag,
294 ((net->cc_mod.rtcc.lbw << 32) | nbw),
295 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
296 net->flight_size,
297 probepoint);
298 if (net->cc_mod.rtcc.steady_step) {
299 oth = net->cc_mod.rtcc.vol_reduce;
300 oth <<= 16;
301 oth |= net->cc_mod.rtcc.step_cnt;
302 oth <<= 16;
303 oth |= net->cc_mod.rtcc.last_step_state;
304 SDT_PROBE(sctp, cwnd, net, rttstep,
305 vtag,
306 ((net->cc_mod.rtcc.lbw << 32) | nbw),
307 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
308 oth,
309 probepoint);
310 if ((net->cc_mod.rtcc.last_step_state == 5) &&
311 (net->cc_mod.rtcc.step_cnt > net->cc_mod.rtcc.steady_step)) {
312 /* Step down worked */
313 net->cc_mod.rtcc.step_cnt = 0;
314 return (1);
315 } else {
316 net->cc_mod.rtcc.last_step_state = 6;
317 net->cc_mod.rtcc.step_cnt = 0;
318 }
319 }
320 net->cc_mod.rtcc.lbw = nbw;
321 net->cc_mod.rtcc.lbw_rtt = net->rtt;
322 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd;
323 if (inst_ind == SCTP_INST_GAINING)
324 return (1);
325 else if (inst_ind == SCTP_INST_NEUTRAL)
326 return (1);
327 else
328 return (0);
329 }
330 /*
331 * Ok bw and rtt remained the same .. no update to any
332 */
333 /* Probe point 7 */
334 probepoint |= ((7 << 16) | net->cc_mod.rtcc.ret_from_eq);
335 SDT_PROBE(sctp, cwnd, net, rttvar,
336 vtag,
337 ((net->cc_mod.rtcc.lbw << 32) | nbw),
338 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
339 net->flight_size,
340 probepoint);
341 if ((net->cc_mod.rtcc.steady_step) && (inst_ind != SCTP_INST_LOOSING)) {
342 if (net->cc_mod.rtcc.last_step_state == 5)
343 net->cc_mod.rtcc.step_cnt++;
344 else
345 net->cc_mod.rtcc.step_cnt = 1;
346 net->cc_mod.rtcc.last_step_state = 5;
347 if ((net->cc_mod.rtcc.step_cnt == net->cc_mod.rtcc.steady_step) ||
348 ((net->cc_mod.rtcc.step_cnt > net->cc_mod.rtcc.steady_step) &&
349 ((net->cc_mod.rtcc.step_cnt % net->cc_mod.rtcc.steady_step) == 0))) {
350 /* Try a step down */
351 if (net->cwnd > (4 * net->mtu)) {
352 net->cwnd -= net->mtu;
353 net->cc_mod.rtcc.vol_reduce++;
354 return (1);
355 } else {
356 net->cc_mod.rtcc.step_cnt = 0;
357 }
358 }
359 }
360 if (inst_ind == SCTP_INST_GAINING)
361 return (1);
362 else if (inst_ind == SCTP_INST_NEUTRAL)
363 return (1);
364 else
365 return ((int)net->cc_mod.rtcc.ret_from_eq);
366 }
367
368 static int
369 cc_bw_decrease(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw, uint64_t rtt_offset,
370 uint64_t vtag, uint8_t inst_ind)
371 {
372 uint64_t oth, probepoint;
373
374 /* Bandwidth decreased. */
375 probepoint = (((uint64_t) net->cwnd) << 32);
376 if (net->rtt > net->cc_mod.rtcc.lbw_rtt + rtt_offset) {
377 /* rtt increased */
378 /* Did we add more */
379 if ((net->cwnd > net->cc_mod.rtcc.cwnd_at_bw_set) &&
380 (inst_ind != SCTP_INST_LOOSING)) {
381 /* We caused it maybe.. back off? */
382 /* PROBE POINT 1 */
383 probepoint |= ((1 << 16) | 1);
384 SDT_PROBE(sctp, cwnd, net, rttvar,
385 vtag,
386 ((net->cc_mod.rtcc.lbw << 32) | nbw),
387 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
388 net->flight_size,
389 probepoint);
390 if (net->cc_mod.rtcc.ret_from_eq) {
391 /*
392 * Switch over to CA if we are less
393 * aggressive
394 */
395 net->ssthresh = net->cwnd - 1;
396 net->partial_bytes_acked = 0;
397 }
398 return (1);
399 }
400 /* Probe point 2 */
401 probepoint |= ((2 << 16) | 0);
402 SDT_PROBE(sctp, cwnd, net, rttvar,
403 vtag,
404 ((net->cc_mod.rtcc.lbw << 32) | nbw),
405 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
406 net->flight_size,
407 probepoint);
408 /* Someone else - fight for more? */
409 if (net->cc_mod.rtcc.steady_step) {
410 oth = net->cc_mod.rtcc.vol_reduce;
411 oth <<= 16;
412 oth |= net->cc_mod.rtcc.step_cnt;
413 oth <<= 16;
414 oth |= net->cc_mod.rtcc.last_step_state;
415 SDT_PROBE(sctp, cwnd, net, rttstep,
416 vtag,
417 ((net->cc_mod.rtcc.lbw << 32) | nbw),
418 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
419 oth,
420 probepoint);
421 /*
422 * Did we voluntarily give up some? if so take one
423 * back please
424 */
425 if ((net->cc_mod.rtcc.vol_reduce) &&
426 (inst_ind != SCTP_INST_GAINING)) {
427 net->cwnd += net->mtu;
428 net->cc_mod.rtcc.vol_reduce--;
429 }
430 net->cc_mod.rtcc.last_step_state = 2;
431 net->cc_mod.rtcc.step_cnt = 0;
432 }
433 goto out_decision;
434 } else if (net->rtt < net->cc_mod.rtcc.lbw_rtt - rtt_offset) {
435 /* bw & rtt decreased */
436 /* Probe point 3 */
437 probepoint |= ((3 << 16) | 0);
438 SDT_PROBE(sctp, cwnd, net, rttvar,
439 vtag,
440 ((net->cc_mod.rtcc.lbw << 32) | nbw),
441 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
442 net->flight_size,
443 probepoint);
444 if (net->cc_mod.rtcc.steady_step) {
445 oth = net->cc_mod.rtcc.vol_reduce;
446 oth <<= 16;
447 oth |= net->cc_mod.rtcc.step_cnt;
448 oth <<= 16;
449 oth |= net->cc_mod.rtcc.last_step_state;
450 SDT_PROBE(sctp, cwnd, net, rttstep,
451 vtag,
452 ((net->cc_mod.rtcc.lbw << 32) | nbw),
453 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
454 oth,
455 probepoint);
456 if ((net->cc_mod.rtcc.vol_reduce) &&
457 (inst_ind != SCTP_INST_GAINING)) {
458 net->cwnd += net->mtu;
459 net->cc_mod.rtcc.vol_reduce--;
460 }
461 net->cc_mod.rtcc.last_step_state = 3;
462 net->cc_mod.rtcc.step_cnt = 0;
463 }
464 goto out_decision;
465 }
466 /* The bw decreased but rtt stayed the same */
467 /* Probe point 4 */
468 probepoint |= ((4 << 16) | 0);
469 SDT_PROBE(sctp, cwnd, net, rttvar,
470 vtag,
471 ((net->cc_mod.rtcc.lbw << 32) | nbw),
472 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
473 net->flight_size,
474 probepoint);
475 if (net->cc_mod.rtcc.steady_step) {
476 oth = net->cc_mod.rtcc.vol_reduce;
477 oth <<= 16;
478 oth |= net->cc_mod.rtcc.step_cnt;
479 oth <<= 16;
480 oth |= net->cc_mod.rtcc.last_step_state;
481 SDT_PROBE(sctp, cwnd, net, rttstep,
482 vtag,
483 ((net->cc_mod.rtcc.lbw << 32) | nbw),
484 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
485 oth,
486 probepoint);
487 if ((net->cc_mod.rtcc.vol_reduce) &&
488 (inst_ind != SCTP_INST_GAINING)) {
489 net->cwnd += net->mtu;
490 net->cc_mod.rtcc.vol_reduce--;
491 }
492 net->cc_mod.rtcc.last_step_state = 4;
493 net->cc_mod.rtcc.step_cnt = 0;
494 }
495 out_decision:
496 net->cc_mod.rtcc.lbw = nbw;
497 net->cc_mod.rtcc.lbw_rtt = net->rtt;
498 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd;
499 if (inst_ind == SCTP_INST_GAINING) {
500 return (1);
501 } else {
502 return (0);
503 }
504 }
505
506 static int
507 cc_bw_increase(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw, uint64_t vtag)
508 {
509 uint64_t oth, probepoint;
510
511 /*
512 * BW increased, so update and return 0, since all actions in our
513 * table say to do the normal CC update. Note that we pay no
514 * attention to the inst_ind since our overall sum is increasing.
515 */
516 /* PROBE POINT 0 */
517 probepoint = (((uint64_t) net->cwnd) << 32);
518 SDT_PROBE(sctp, cwnd, net, rttvar,
519 vtag,
520 ((net->cc_mod.rtcc.lbw << 32) | nbw),
521 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
522 net->flight_size,
523 probepoint);
524 if (net->cc_mod.rtcc.steady_step) {
525 oth = net->cc_mod.rtcc.vol_reduce;
526 oth <<= 16;
527 oth |= net->cc_mod.rtcc.step_cnt;
528 oth <<= 16;
529 oth |= net->cc_mod.rtcc.last_step_state;
530 SDT_PROBE(sctp, cwnd, net, rttstep,
531 vtag,
532 ((net->cc_mod.rtcc.lbw << 32) | nbw),
533 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
534 oth,
535 probepoint);
536 net->cc_mod.rtcc.last_step_state = 0;
537 net->cc_mod.rtcc.step_cnt = 0;
538 net->cc_mod.rtcc.vol_reduce = 0;
539 }
540 net->cc_mod.rtcc.lbw = nbw;
541 net->cc_mod.rtcc.lbw_rtt = net->rtt;
542 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd;
543 return (0);
544 }
545
546 /* RTCC Algoritm to limit growth of cwnd, return
547 * true if you want to NOT allow cwnd growth
548 */
549 static int
550 cc_bw_limit(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw)
551 {
552 uint64_t bw_offset, rtt_offset;
553 uint64_t probepoint, rtt, vtag;
554 uint64_t bytes_for_this_rtt, inst_bw;
555 uint64_t div, inst_off;
556 int bw_shift;
557 uint8_t inst_ind;
558 int ret;
559
560 /*-
561 * Here we need to see if we want
562 * to limit cwnd growth due to increase
563 * in overall rtt but no increase in bw.
564 * We use the following table to figure
565 * out what we should do. When we return
566 * 0, cc update goes on as planned. If we
567 * return 1, then no cc update happens and cwnd
568 * stays where it is at.
569 * ----------------------------------
570 * BW | RTT | Action
571 * *********************************
572 * INC | INC | return 0
573 * ----------------------------------
574 * INC | SAME | return 0
575 * ----------------------------------
576 * INC | DECR | return 0
577 * ----------------------------------
578 * SAME | INC | return 1
579 * ----------------------------------
580 * SAME | SAME | return 1
581 * ----------------------------------
582 * SAME | DECR | return 0
583 * ----------------------------------
584 * DECR | INC | return 0 or 1 based on if we caused.
585 * ----------------------------------
586 * DECR | SAME | return 0
587 * ----------------------------------
588 * DECR | DECR | return 0
589 * ----------------------------------
590 *
591 * We are a bit fuzz on what an increase or
592 * decrease is. For BW it is the same if
593 * it did not change within 1/64th. For
594 * RTT it stayed the same if it did not
595 * change within 1/32nd
596 */
597 bw_shift = SCTP_BASE_SYSCTL(sctp_rttvar_bw);
598 rtt = stcb->asoc.my_vtag;
599 vtag = (rtt << 32) | (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) | (stcb->rport);
600 probepoint = (((uint64_t) net->cwnd) << 32);
601 rtt = net->rtt;
602 if (net->cc_mod.rtcc.rtt_set_this_sack) {
603 net->cc_mod.rtcc.rtt_set_this_sack = 0;
604 bytes_for_this_rtt = net->cc_mod.rtcc.bw_bytes - net->cc_mod.rtcc.bw_bytes_at_last_rttc;
605 net->cc_mod.rtcc.bw_bytes_at_last_rttc = net->cc_mod.rtcc.bw_bytes;
606 if (net->rtt) {
607 div = net->rtt / 1000;
608 if (div) {
609 inst_bw = bytes_for_this_rtt / div;
610 inst_off = inst_bw >> bw_shift;
611 if (inst_bw > nbw)
612 inst_ind = SCTP_INST_GAINING;
613 else if ((inst_bw + inst_off) < nbw)
614 inst_ind = SCTP_INST_LOOSING;
615 else
616 inst_ind = SCTP_INST_NEUTRAL;
617 probepoint |= ((0xb << 16) | inst_ind);
618 } else {
619 inst_ind = net->cc_mod.rtcc.last_inst_ind;
620 inst_bw = bytes_for_this_rtt / (uint64_t) (net->rtt);
621 /* Can't determine do not change */
622 probepoint |= ((0xc << 16) | inst_ind);
623 }
624 } else {
625 inst_ind = net->cc_mod.rtcc.last_inst_ind;
626 inst_bw = bytes_for_this_rtt;
627 /* Can't determine do not change */
628 probepoint |= ((0xd << 16) | inst_ind);
629 }
630 SDT_PROBE(sctp, cwnd, net, rttvar,
631 vtag,
632 ((nbw << 32) | inst_bw),
633 ((net->cc_mod.rtcc.lbw_rtt << 32) | rtt),
634 net->flight_size,
635 probepoint);
636 } else {
637 /* No rtt measurement, use last one */
638 inst_ind = net->cc_mod.rtcc.last_inst_ind;
639 }
640 bw_offset = net->cc_mod.rtcc.lbw >> bw_shift;
641 if (nbw > net->cc_mod.rtcc.lbw + bw_offset) {
642 ret = cc_bw_increase(stcb, net, nbw, vtag);
643 goto out;
644 }
645 rtt_offset = net->cc_mod.rtcc.lbw_rtt >> SCTP_BASE_SYSCTL(sctp_rttvar_rtt);
646 if (nbw < net->cc_mod.rtcc.lbw - bw_offset) {
647 ret = cc_bw_decrease(stcb, net, nbw, rtt_offset, vtag, inst_ind);
648 goto out;
649 }
650 /*
651 * If we reach here then we are in a situation where the bw stayed
652 * the same.
653 */
654 ret = cc_bw_same(stcb, net, nbw, rtt_offset, vtag, inst_ind);
655 out:
656 net->cc_mod.rtcc.last_inst_ind = inst_ind;
657 return (ret);
658 }
659
660 static void
661 sctp_cwnd_update_after_sack_common(struct sctp_tcb *stcb,
662 struct sctp_association *asoc,
663 int accum_moved, int reneged_all SCTP_UNUSED, int will_exit, int use_rtcc)
664 {
665 struct sctp_nets *net;
666 int old_cwnd;
667 uint32_t t_ssthresh, t_cwnd, incr;
668 uint64_t t_ucwnd_sbw;
669 uint64_t t_path_mptcp;
670 uint64_t mptcp_like_alpha;
671 uint32_t srtt;
672 uint64_t max_path;
673
674 /* MT FIXME: Don't compute this over and over again */
675 t_ssthresh = 0;
676 t_cwnd = 0;
677 t_ucwnd_sbw = 0;
678 t_path_mptcp = 0;
679 mptcp_like_alpha = 1;
680 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) ||
681 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2) ||
682 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_MPTCP)) {
683 max_path = 0;
684 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
685 t_ssthresh += net->ssthresh;
686 t_cwnd += net->cwnd;
687 /* lastsa>>3; we don't need to devide ... */
688 srtt = net->lastsa;
689 if (srtt > 0) {
690 uint64_t tmp;
691
692 t_ucwnd_sbw += (uint64_t) net->cwnd / (uint64_t) srtt;
693 t_path_mptcp += (((uint64_t) net->cwnd) << SHIFT_MPTCP_MULTI_Z) /
694 (((uint64_t) net->mtu) * (uint64_t) srtt);
695 tmp = (((uint64_t) net->cwnd) << SHIFT_MPTCP_MULTI_N) /
696 ((uint64_t) net->mtu * (uint64_t) (srtt * srtt));
697 if (tmp > max_path) {
698 max_path = tmp;
699 }
700 }
701 }
702 if (t_path_mptcp > 0) {
703 mptcp_like_alpha = max_path / (t_path_mptcp * t_path_mptcp);
704 } else {
705 mptcp_like_alpha = 1;
706 }
707 }
708 if (t_ssthresh == 0) {
709 t_ssthresh = 1;
710 }
711 if (t_ucwnd_sbw == 0) {
712 t_ucwnd_sbw = 1;
713 }
714 /******************************/
715 /* update cwnd and Early FR */
716 /******************************/
717 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
718
719 #ifdef JANA_CMT_FAST_RECOVERY
720 /*
721 * CMT fast recovery code. Need to debug.
722 */
723 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
724 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) ||
725 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) {
726 net->will_exit_fast_recovery = 1;
727 }
728 }
729 #endif
730 /* if nothing was acked on this destination skip it */
731 if (net->net_ack == 0) {
732 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
733 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
734 }
735 continue;
736 }
737 #ifdef JANA_CMT_FAST_RECOVERY
738 /*
739 * CMT fast recovery code
740 */
741 /*
742 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery
743 * && net->will_exit_fast_recovery == 0) { @@@ Do something
744 * } else if (sctp_cmt_on_off == 0 &&
745 * asoc->fast_retran_loss_recovery && will_exit == 0) {
746 */
747 #endif
748
749 if (asoc->fast_retran_loss_recovery &&
750 (will_exit == 0) &&
751 (asoc->sctp_cmt_on_off == 0)) {
752 /*
753 * If we are in loss recovery we skip any cwnd
754 * update
755 */
756 return;
757 }
758 /*
759 * Did any measurements go on for this network?
760 */
761 if (use_rtcc && (net->cc_mod.rtcc.tls_needs_set > 0)) {
762 uint64_t nbw;
763
764 /*
765 * At this point our bw_bytes has been updated by
766 * incoming sack information.
767 *
768 * But our bw may not yet be set.
769 *
770 */
771 if ((net->cc_mod.rtcc.new_tot_time / 1000) > 0) {
772 nbw = net->cc_mod.rtcc.bw_bytes / (net->cc_mod.rtcc.new_tot_time / 1000);
773 } else {
774 nbw = net->cc_mod.rtcc.bw_bytes;
775 }
776 if (net->cc_mod.rtcc.lbw) {
777 if (cc_bw_limit(stcb, net, nbw)) {
778 /* Hold here, no update */
779 continue;
780 }
781 } else {
782 uint64_t vtag, probepoint;
783
784 probepoint = (((uint64_t) net->cwnd) << 32);
785 probepoint |= ((0xa << 16) | 0);
786 vtag = (net->rtt << 32) |
787 (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) |
788 (stcb->rport);
789
790 SDT_PROBE(sctp, cwnd, net, rttvar,
791 vtag,
792 nbw,
793 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
794 net->flight_size,
795 probepoint);
796 net->cc_mod.rtcc.lbw = nbw;
797 net->cc_mod.rtcc.lbw_rtt = net->rtt;
798 if (net->cc_mod.rtcc.rtt_set_this_sack) {
799 net->cc_mod.rtcc.rtt_set_this_sack = 0;
800 net->cc_mod.rtcc.bw_bytes_at_last_rttc = net->cc_mod.rtcc.bw_bytes;
801 }
802 }
803 }
804 /*
805 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
806 * moved.
807 */
808 if (accum_moved ||
809 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) {
810 /* If the cumulative ack moved we can proceed */
811 if (net->cwnd <= net->ssthresh) {
812 /* We are in slow start */
813 if (net->flight_size + net->net_ack >= net->cwnd) {
814 uint32_t limit;
815
816 old_cwnd = net->cwnd;
817 switch (asoc->sctp_cmt_on_off) {
818 case SCTP_CMT_RPV1:
819 limit = (uint32_t) (((uint64_t) net->mtu *
820 (uint64_t) SCTP_BASE_SYSCTL(sctp_L2_abc_variable) *
821 (uint64_t) net->ssthresh) /
822 (uint64_t) t_ssthresh);
823 incr = (uint32_t) (((uint64_t) net->net_ack *
824 (uint64_t) net->ssthresh) /
825 (uint64_t) t_ssthresh);
826 if (incr > limit) {
827 incr = limit;
828 }
829 if (incr == 0) {
830 incr = 1;
831 }
832 break;
833 case SCTP_CMT_RPV2:
834 /*
835 * lastsa>>3; we don't need
836 * to divide ...
837 */
838 srtt = net->lastsa;
839 if (srtt == 0) {
840 srtt = 1;
841 }
842 limit = (uint32_t) (((uint64_t) net->mtu *
843 (uint64_t) SCTP_BASE_SYSCTL(sctp_L2_abc_variable) *
844 (uint64_t) net->cwnd) /
845 ((uint64_t) srtt * t_ucwnd_sbw));
846 /* INCREASE FACTOR */
847 incr = (uint32_t) (((uint64_t) net->net_ack *
848 (uint64_t) net->cwnd) /
849 ((uint64_t) srtt * t_ucwnd_sbw));
850 /* INCREASE FACTOR */
851 if (incr > limit) {
852 incr = limit;
853 }
854 if (incr == 0) {
855 incr = 1;
856 }
857 break;
858 case SCTP_CMT_MPTCP:
859 limit = (uint32_t) (((uint64_t) net->mtu *
860 mptcp_like_alpha *
861 (uint64_t) SCTP_BASE_SYSCTL(sctp_L2_abc_variable)) >>
862 SHIFT_MPTCP_MULTI);
863 incr = (uint32_t) (((uint64_t) net->net_ack *
864 mptcp_like_alpha) >>
865 SHIFT_MPTCP_MULTI);
866 if (incr > limit) {
867 incr = limit;
868 }
869 if (incr > net->net_ack) {
870 incr = net->net_ack;
871 }
872 if (incr > net->mtu) {
873 incr = net->mtu;
874 }
875 break;
876 default:
877 incr = net->net_ack;
878 if (incr > net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable)) {
879 incr = net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable);
880 }
881 break;
882 }
883 net->cwnd += incr;
884 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
885 sctp_log_cwnd(stcb, net, incr,
886 SCTP_CWND_LOG_FROM_SS);
887 }
888 SDT_PROBE(sctp, cwnd, net, ack,
889 stcb->asoc.my_vtag,
890 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
891 net,
892 old_cwnd, net->cwnd);
893 } else {
894 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
895 sctp_log_cwnd(stcb, net, net->net_ack,
896 SCTP_CWND_LOG_NOADV_SS);
897 }
898 }
899 } else {
900 /* We are in congestion avoidance */
901 /*
902 * Add to pba
903 */
904 net->partial_bytes_acked += net->net_ack;
905
906 if ((net->flight_size + net->net_ack >= net->cwnd) &&
907 (net->partial_bytes_acked >= net->cwnd)) {
908 net->partial_bytes_acked -= net->cwnd;
909 old_cwnd = net->cwnd;
910 switch (asoc->sctp_cmt_on_off) {
911 case SCTP_CMT_RPV1:
912 incr = (uint32_t) (((uint64_t) net->mtu *
913 (uint64_t) net->ssthresh) /
914 (uint64_t) t_ssthresh);
915 if (incr == 0) {
916 incr = 1;
917 }
918 break;
919 case SCTP_CMT_RPV2:
920 /*
921 * lastsa>>3; we don't need
922 * to divide ...
923 */
924 srtt = net->lastsa;
925 if (srtt == 0) {
926 srtt = 1;
927 }
928 incr = (uint32_t) ((uint64_t) net->mtu *
929 (uint64_t) net->cwnd /
930 ((uint64_t) srtt *
931 t_ucwnd_sbw));
932 /* INCREASE FACTOR */
933 if (incr == 0) {
934 incr = 1;
935 }
936 break;
937 case SCTP_CMT_MPTCP:
938 incr = (uint32_t) ((mptcp_like_alpha *
939 (uint64_t) net->cwnd) >>
940 SHIFT_MPTCP_MULTI);
941 if (incr > net->mtu) {
942 incr = net->mtu;
943 }
944 break;
945 default:
946 incr = net->mtu;
947 break;
948 }
949 net->cwnd += incr;
950 SDT_PROBE(sctp, cwnd, net, ack,
951 stcb->asoc.my_vtag,
952 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
953 net,
954 old_cwnd, net->cwnd);
955 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
956 sctp_log_cwnd(stcb, net, net->mtu,
957 SCTP_CWND_LOG_FROM_CA);
958 }
959 } else {
960 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
961 sctp_log_cwnd(stcb, net, net->net_ack,
962 SCTP_CWND_LOG_NOADV_CA);
963 }
964 }
965 }
966 } else {
967 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
968 sctp_log_cwnd(stcb, net, net->mtu,
969 SCTP_CWND_LOG_NO_CUMACK);
970 }
971 }
972 }
973 }
974
975 static void
976 sctp_cwnd_update_exit_pf_common(struct sctp_tcb *stcb, struct sctp_nets *net)
977 {
978 int old_cwnd;
979
980 old_cwnd = net->cwnd;
981 net->cwnd = net->mtu;
982 SDT_PROBE(sctp, cwnd, net, ack,
983 stcb->asoc.my_vtag, ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), net,
984 old_cwnd, net->cwnd);
985 SCTPDBG(SCTP_DEBUG_INDATA1, "Destination %p moved from PF to reachable with cwnd %d.\n",
986 net, net->cwnd);
987 }
988
989
990 static void
991 sctp_cwnd_update_after_timeout(struct sctp_tcb *stcb, struct sctp_nets *net)
992 {
993 int old_cwnd = net->cwnd;
994 uint32_t t_ssthresh, t_cwnd;
995 uint64_t t_ucwnd_sbw;
996
997 /* MT FIXME: Don't compute this over and over again */
998 t_ssthresh = 0;
999 t_cwnd = 0;
1000 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) ||
1001 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2)) {
1002 struct sctp_nets *lnet;
1003 uint32_t srtt;
1004
1005 t_ucwnd_sbw = 0;
1006 TAILQ_FOREACH(lnet, &stcb->asoc.nets, sctp_next) {
1007 t_ssthresh += lnet->ssthresh;
1008 t_cwnd += lnet->cwnd;
1009 srtt = lnet->lastsa;
1010 /* lastsa>>3; we don't need to divide ... */
1011 if (srtt > 0) {
1012 t_ucwnd_sbw += (uint64_t) lnet->cwnd / (uint64_t) srtt;
1013 }
1014 }
1015 if (t_ssthresh < 1) {
1016 t_ssthresh = 1;
1017 }
1018 if (t_ucwnd_sbw < 1) {
1019 t_ucwnd_sbw = 1;
1020 }
1021 if (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) {
1022 net->ssthresh = (uint32_t) (((uint64_t) 4 *
1023 (uint64_t) net->mtu *
1024 (uint64_t) net->ssthresh) /
1025 (uint64_t) t_ssthresh);
1026 } else {
1027 uint64_t cc_delta;
1028
1029 srtt = net->lastsa;
1030 /* lastsa>>3; we don't need to divide ... */
1031 if (srtt == 0) {
1032 srtt = 1;
1033 }
1034 cc_delta = t_ucwnd_sbw * (uint64_t) srtt / 2;
1035 if (cc_delta < t_cwnd) {
1036 net->ssthresh = (uint32_t) ((uint64_t) t_cwnd - cc_delta);
1037 } else {
1038 net->ssthresh = net->mtu;
1039 }
1040 }
1041 if ((net->cwnd > t_cwnd / 2) &&
1042 (net->ssthresh < net->cwnd - t_cwnd / 2)) {
1043 net->ssthresh = net->cwnd - t_cwnd / 2;
1044 }
1045 if (net->ssthresh < net->mtu) {
1046 net->ssthresh = net->mtu;
1047 }
1048 } else {
1049 net->ssthresh = max(net->cwnd / 2, 4 * net->mtu);
1050 }
1051 net->cwnd = net->mtu;
1052 net->partial_bytes_acked = 0;
1053 SDT_PROBE(sctp, cwnd, net, to,
1054 stcb->asoc.my_vtag,
1055 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
1056 net,
1057 old_cwnd, net->cwnd);
1058 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1059 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX);
1060 }
1061 }
1062
1063 static void
1064 sctp_cwnd_update_after_ecn_echo_common(struct sctp_tcb *stcb, struct sctp_nets *net,
1065 int in_window, int num_pkt_lost, int use_rtcc)
1066 {
1067 int old_cwnd = net->cwnd;
1068
1069 if ((use_rtcc) && (net->lan_type == SCTP_LAN_LOCAL) && (net->cc_mod.rtcc.use_dccc_ecn)) {
1070 /* Data center Congestion Control */
1071 if (in_window == 0) {
1072 /*
1073 * Go to CA with the cwnd at the point we sent the
1074 * TSN that was marked with a CE.
1075 */
1076 if (net->ecn_prev_cwnd < net->cwnd) {
1077 /* Restore to prev cwnd */
1078 net->cwnd = net->ecn_prev_cwnd - (net->mtu * num_pkt_lost);
1079 } else {
1080 /* Just cut in 1/2 */
1081 net->cwnd /= 2;
1082 }
1083 /* Drop to CA */
1084 net->ssthresh = net->cwnd - (num_pkt_lost * net->mtu);
1085 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1086 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
1087 }
1088 } else {
1089 /*
1090 * Further tuning down required over the drastic
1091 * orginal cut
1092 */
1093 net->ssthresh -= (net->mtu * num_pkt_lost);
1094 net->cwnd -= (net->mtu * num_pkt_lost);
1095 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1096 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
1097 }
1098 }
1099 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
1100 } else {
1101 if (in_window == 0) {
1102 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
1103 net->ssthresh = net->cwnd / 2;
1104 if (net->ssthresh < net->mtu) {
1105 net->ssthresh = net->mtu;
1106 /*
1107 * here back off the timer as well, to slow
1108 * us down
1109 */
1110 net->RTO <<= 1;
1111 }
1112 net->cwnd = net->ssthresh;
1113 SDT_PROBE(sctp, cwnd, net, ecn,
1114 stcb->asoc.my_vtag,
1115 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
1116 net,
1117 old_cwnd, net->cwnd);
1118 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1119 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
1120 }
1121 }
1122 }
1123
1124 }
1125
1126 static void
1127 sctp_cwnd_update_after_packet_dropped(struct sctp_tcb *stcb,
1128 struct sctp_nets *net, struct sctp_pktdrop_chunk *cp,
1129 uint32_t * bottle_bw, uint32_t * on_queue)
1130 {
1131 uint32_t bw_avail;
1132 int rtt;
1133 unsigned int incr;
1134 int old_cwnd = net->cwnd;
1135
1136 /* need real RTT in msd for this calc */
1137 rtt = net->rtt / 1000;
1138 /* get bottle neck bw */
1139 *bottle_bw = ntohl(cp->bottle_bw);
1140 /* and whats on queue */
1141 *on_queue = ntohl(cp->current_onq);
1142 /*
1143 * adjust the on-queue if our flight is more it could be that the
1144 * router has not yet gotten data "in-flight" to it
1145 */
1146 if (*on_queue < net->flight_size)
1147 *on_queue = net->flight_size;
1148 /* calculate the available space */
1149 bw_avail = (*bottle_bw * rtt) / 1000;
1150 if (bw_avail > *bottle_bw) {
1151 /*
1152 * Cap the growth to no more than the bottle neck. This can
1153 * happen as RTT slides up due to queues. It also means if
1154 * you have more than a 1 second RTT with a empty queue you
1155 * will be limited to the bottle_bw per second no matter if
1156 * other points have 1/2 the RTT and you could get more
1157 * out...
1158 */
1159 bw_avail = *bottle_bw;
1160 }
1161 if (*on_queue > bw_avail) {
1162 /*
1163 * No room for anything else don't allow anything else to be
1164 * "added to the fire".
1165 */
1166 int seg_inflight, seg_onqueue, my_portion;
1167
1168 net->partial_bytes_acked = 0;
1169
1170 /* how much are we over queue size? */
1171 incr = *on_queue - bw_avail;
1172 if (stcb->asoc.seen_a_sack_this_pkt) {
1173 /*
1174 * undo any cwnd adjustment that the sack might have
1175 * made
1176 */
1177 net->cwnd = net->prev_cwnd;
1178 }
1179 /* Now how much of that is mine? */
1180 seg_inflight = net->flight_size / net->mtu;
1181 seg_onqueue = *on_queue / net->mtu;
1182 my_portion = (incr * seg_inflight) / seg_onqueue;
1183
1184 /* Have I made an adjustment already */
1185 if (net->cwnd > net->flight_size) {
1186 /*
1187 * for this flight I made an adjustment we need to
1188 * decrease the portion by a share our previous
1189 * adjustment.
1190 */
1191 int diff_adj;
1192
1193 diff_adj = net->cwnd - net->flight_size;
1194 if (diff_adj > my_portion)
1195 my_portion = 0;
1196 else
1197 my_portion -= diff_adj;
1198 }
1199 /*
1200 * back down to the previous cwnd (assume we have had a sack
1201 * before this packet). minus what ever portion of the
1202 * overage is my fault.
1203 */
1204 net->cwnd -= my_portion;
1205
1206 /* we will NOT back down more than 1 MTU */
1207 if (net->cwnd <= net->mtu) {
1208 net->cwnd = net->mtu;
1209 }
1210 /* force into CA */
1211 net->ssthresh = net->cwnd - 1;
1212 } else {
1213 /*
1214 * Take 1/4 of the space left or max burst up .. whichever
1215 * is less.
1216 */
1217 incr = (bw_avail - *on_queue) >> 2;
1218 if ((stcb->asoc.max_burst > 0) &&
1219 (stcb->asoc.max_burst * net->mtu < incr)) {
1220 incr = stcb->asoc.max_burst * net->mtu;
1221 }
1222 net->cwnd += incr;
1223 }
1224 if (net->cwnd > bw_avail) {
1225 /* We can't exceed the pipe size */
1226 net->cwnd = bw_avail;
1227 }
1228 if (net->cwnd < net->mtu) {
1229 /* We always have 1 MTU */
1230 net->cwnd = net->mtu;
1231 }
1232 if (net->cwnd - old_cwnd != 0) {
1233 /* log only changes */
1234 SDT_PROBE(sctp, cwnd, net, pd,
1235 stcb->asoc.my_vtag,
1236 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
1237 net,
1238 old_cwnd, net->cwnd);
1239 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1240 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
1241 SCTP_CWND_LOG_FROM_SAT);
1242 }
1243 }
1244 }
1245
1246 static void
1247 sctp_cwnd_update_after_output(struct sctp_tcb *stcb,
1248 struct sctp_nets *net, int burst_limit)
1249 {
1250 int old_cwnd = net->cwnd;
1251
1252 if (net->ssthresh < net->cwnd)
1253 net->ssthresh = net->cwnd;
1254 if (burst_limit) {
1255 net->cwnd = (net->flight_size + (burst_limit * net->mtu));
1256 SDT_PROBE(sctp, cwnd, net, bl,
1257 stcb->asoc.my_vtag,
1258 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
1259 net,
1260 old_cwnd, net->cwnd);
1261 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1262 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_BRST);
1263 }
1264 }
1265 }
1266
1267 static void
1268 sctp_cwnd_update_after_sack(struct sctp_tcb *stcb,
1269 struct sctp_association *asoc,
1270 int accum_moved, int reneged_all, int will_exit)
1271 {
1272 /* Passing a zero argument in last disables the rtcc algoritm */
1273 sctp_cwnd_update_after_sack_common(stcb, asoc, accum_moved, reneged_all, will_exit, 0);
1274 }
1275
1276 static void
1277 sctp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net,
1278 int in_window, int num_pkt_lost)
1279 {
1280 /* Passing a zero argument in last disables the rtcc algoritm */
1281 sctp_cwnd_update_after_ecn_echo_common(stcb, net, in_window, num_pkt_lost, 0);
1282 }
1283
1284 /* Here starts the RTCCVAR type CC invented by RRS which
1285 * is a slight mod to RFC2581. We reuse a common routine or
1286 * two since these algoritms are so close and need to
1287 * remain the same.
1288 */
1289 static void
1290 sctp_cwnd_update_rtcc_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net,
1291 int in_window, int num_pkt_lost)
1292 {
1293 sctp_cwnd_update_after_ecn_echo_common(stcb, net, in_window, num_pkt_lost, 1);
1294 }
1295
1296
1297 static
1298 void
1299 sctp_cwnd_update_rtcc_tsn_acknowledged(struct sctp_nets *net,
1300 struct sctp_tmit_chunk *tp1)
1301 {
1302 net->cc_mod.rtcc.bw_bytes += tp1->send_size;
1303 }
1304
1305 static void
1306 sctp_cwnd_prepare_rtcc_net_for_sack(struct sctp_tcb *stcb SCTP_UNUSED,
1307 struct sctp_nets *net)
1308 {
1309 if (net->cc_mod.rtcc.tls_needs_set > 0) {
1310 /* We had a bw measurment going on */
1311 struct timeval ltls;
1312
1313 SCTP_GETPTIME_TIMEVAL(<ls);
1314 timevalsub(<ls, &net->cc_mod.rtcc.tls);
1315 net->cc_mod.rtcc.new_tot_time = (ltls.tv_sec * 1000000) + ltls.tv_usec;
1316 }
1317 }
1318
1319 static void
1320 sctp_cwnd_new_rtcc_transmission_begins(struct sctp_tcb *stcb,
1321 struct sctp_nets *net)
1322 {
1323 uint64_t vtag, probepoint;
1324
1325 if (net->cc_mod.rtcc.lbw) {
1326 /* Clear the old bw.. we went to 0 in-flight */
1327 vtag = (net->rtt << 32) | (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) |
1328 (stcb->rport);
1329 probepoint = (((uint64_t) net->cwnd) << 32);
1330 /* Probe point 8 */
1331 probepoint |= ((8 << 16) | 0);
1332 SDT_PROBE(sctp, cwnd, net, rttvar,
1333 vtag,
1334 ((net->cc_mod.rtcc.lbw << 32) | 0),
1335 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
1336 net->flight_size,
1337 probepoint);
1338 net->cc_mod.rtcc.lbw_rtt = 0;
1339 net->cc_mod.rtcc.cwnd_at_bw_set = 0;
1340 net->cc_mod.rtcc.lbw = 0;
1341 net->cc_mod.rtcc.bw_bytes_at_last_rttc = 0;
1342 net->cc_mod.rtcc.vol_reduce = 0;
1343 net->cc_mod.rtcc.bw_tot_time = 0;
1344 net->cc_mod.rtcc.bw_bytes = 0;
1345 net->cc_mod.rtcc.tls_needs_set = 0;
1346 if (net->cc_mod.rtcc.steady_step) {
1347 net->cc_mod.rtcc.vol_reduce = 0;
1348 net->cc_mod.rtcc.step_cnt = 0;
1349 net->cc_mod.rtcc.last_step_state = 0;
1350 }
1351 if (net->cc_mod.rtcc.ret_from_eq) {
1352 /* less aggressive one - reset cwnd too */
1353 uint32_t cwnd_in_mtu, cwnd;
1354
1355 cwnd_in_mtu = SCTP_BASE_SYSCTL(sctp_initial_cwnd);
1356 if (cwnd_in_mtu == 0) {
1357 /*
1358 * Using 0 means that the value of RFC 4960
1359 * is used.
1360 */
1361 cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
1362 } else {
1363 /*
1364 * We take the minimum of the burst limit
1365 * and the initial congestion window.
1366 */
1367 if ((stcb->asoc.max_burst > 0) && (cwnd_in_mtu > stcb->asoc.max_burst))
1368 cwnd_in_mtu = stcb->asoc.max_burst;
1369 cwnd = (net->mtu - sizeof(struct sctphdr)) * cwnd_in_mtu;
1370 }
1371 if (net->cwnd > cwnd) {
1372 /*
1373 * Only set if we are not a timeout (i.e.
1374 * down to 1 mtu)
1375 */
1376 net->cwnd = cwnd;
1377 }
1378 }
1379 }
1380 }
1381
1382 static void
1383 sctp_set_rtcc_initial_cc_param(struct sctp_tcb *stcb,
1384 struct sctp_nets *net)
1385 {
1386 uint64_t vtag, probepoint;
1387
1388 sctp_set_initial_cc_param(stcb, net);
1389 stcb->asoc.use_precise_time = 1;
1390 probepoint = (((uint64_t) net->cwnd) << 32);
1391 probepoint |= ((9 << 16) | 0);
1392 vtag = (net->rtt << 32) |
1393 (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) |
1394 (stcb->rport);
1395 SDT_PROBE(sctp, cwnd, net, rttvar,
1396 vtag,
1397 0,
1398 0,
1399 0,
1400 probepoint);
1401 net->cc_mod.rtcc.lbw_rtt = 0;
1402 net->cc_mod.rtcc.cwnd_at_bw_set = 0;
1403 net->cc_mod.rtcc.vol_reduce = 0;
1404 net->cc_mod.rtcc.lbw = 0;
1405 net->cc_mod.rtcc.vol_reduce = 0;
1406 net->cc_mod.rtcc.bw_bytes_at_last_rttc = 0;
1407 net->cc_mod.rtcc.bw_tot_time = 0;
1408 net->cc_mod.rtcc.bw_bytes = 0;
1409 net->cc_mod.rtcc.tls_needs_set = 0;
1410 net->cc_mod.rtcc.ret_from_eq = SCTP_BASE_SYSCTL(sctp_rttvar_eqret);
1411 net->cc_mod.rtcc.steady_step = SCTP_BASE_SYSCTL(sctp_steady_step);
1412 net->cc_mod.rtcc.use_dccc_ecn = SCTP_BASE_SYSCTL(sctp_use_dccc_ecn);
1413 net->cc_mod.rtcc.step_cnt = 0;
1414 net->cc_mod.rtcc.last_step_state = 0;
1415
1416
1417 }
1418
1419 static int
1420 sctp_cwnd_rtcc_socket_option(struct sctp_tcb *stcb, int setorget,
1421 struct sctp_cc_option *cc_opt)
1422 {
1423 struct sctp_nets *net;
1424
1425 if (setorget == 1) {
1426 /* a set */
1427 if (cc_opt->option == SCTP_CC_OPT_RTCC_SETMODE) {
1428 if ((cc_opt->aid_value.assoc_value != 0) &&
1429 (cc_opt->aid_value.assoc_value != 1)) {
1430 return (EINVAL);
1431 }
1432 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
1433 net->cc_mod.rtcc.ret_from_eq = cc_opt->aid_value.assoc_value;
1434 }
1435 } else if (cc_opt->option == SCTP_CC_OPT_USE_DCCC_ECN) {
1436 if ((cc_opt->aid_value.assoc_value != 0) &&
1437 (cc_opt->aid_value.assoc_value != 1)) {
1438 return (EINVAL);
1439 }
1440 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
1441 net->cc_mod.rtcc.use_dccc_ecn = cc_opt->aid_value.assoc_value;
1442 }
1443 } else if (cc_opt->option == SCTP_CC_OPT_STEADY_STEP) {
1444 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
1445 net->cc_mod.rtcc.steady_step = cc_opt->aid_value.assoc_value;
1446 }
1447 } else {
1448 return (EINVAL);
1449 }
1450 } else {
1451 /* a get */
1452 if (cc_opt->option == SCTP_CC_OPT_RTCC_SETMODE) {
1453 net = TAILQ_FIRST(&stcb->asoc.nets);
1454 if (net == NULL) {
1455 return (EFAULT);
1456 }
1457 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.ret_from_eq;
1458 } else if (cc_opt->option == SCTP_CC_OPT_USE_DCCC_ECN) {
1459 net = TAILQ_FIRST(&stcb->asoc.nets);
1460 if (net == NULL) {
1461 return (EFAULT);
1462 }
1463 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.use_dccc_ecn;
1464 } else if (cc_opt->option == SCTP_CC_OPT_STEADY_STEP) {
1465 net = TAILQ_FIRST(&stcb->asoc.nets);
1466 if (net == NULL) {
1467 return (EFAULT);
1468 }
1469 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.steady_step;
1470 } else {
1471 return (EINVAL);
1472 }
1473 }
1474 return (0);
1475 }
1476
1477 static void
1478 sctp_cwnd_update_rtcc_packet_transmitted(struct sctp_tcb *stcb SCTP_UNUSED,
1479 struct sctp_nets *net)
1480 {
1481 if (net->cc_mod.rtcc.tls_needs_set == 0) {
1482 SCTP_GETPTIME_TIMEVAL(&net->cc_mod.rtcc.tls);
1483 net->cc_mod.rtcc.tls_needs_set = 2;
1484 }
1485 }
1486
1487 static void
1488 sctp_cwnd_update_rtcc_after_sack(struct sctp_tcb *stcb,
1489 struct sctp_association *asoc,
1490 int accum_moved, int reneged_all, int will_exit)
1491 {
1492 /* Passing a one argument at the last enables the rtcc algoritm */
1493 sctp_cwnd_update_after_sack_common(stcb, asoc, accum_moved, reneged_all, will_exit, 1);
1494 }
1495
1496 static void
1497 sctp_rtt_rtcc_calculated(struct sctp_tcb *stcb SCTP_UNUSED,
1498 struct sctp_nets *net,
1499 struct timeval *now SCTP_UNUSED)
1500 {
1501 net->cc_mod.rtcc.rtt_set_this_sack = 1;
1502 }
1503
1504 /* Here starts Sally Floyds HS-TCP */
1505
1506 struct sctp_hs_raise_drop {
1507 int32_t cwnd;
1508 int32_t increase;
1509 int32_t drop_percent;
1510 };
1511
1512 #define SCTP_HS_TABLE_SIZE 73
1513
1514 struct sctp_hs_raise_drop sctp_cwnd_adjust[SCTP_HS_TABLE_SIZE] = {
1515 {38, 1, 50}, /* 0 */
1516 {118, 2, 44}, /* 1 */
1517 {221, 3, 41}, /* 2 */
1518 {347, 4, 38}, /* 3 */
1519 {495, 5, 37}, /* 4 */
1520 {663, 6, 35}, /* 5 */
1521 {851, 7, 34}, /* 6 */
1522 {1058, 8, 33}, /* 7 */
1523 {1284, 9, 32}, /* 8 */
1524 {1529, 10, 31}, /* 9 */
1525 {1793, 11, 30}, /* 10 */
1526 {2076, 12, 29}, /* 11 */
1527 {2378, 13, 28}, /* 12 */
1528 {2699, 14, 28}, /* 13 */
1529 {3039, 15, 27}, /* 14 */
1530 {3399, 16, 27}, /* 15 */
1531 {3778, 17, 26}, /* 16 */
1532 {4177, 18, 26}, /* 17 */
1533 {4596, 19, 25}, /* 18 */
1534 {5036, 20, 25}, /* 19 */
1535 {5497, 21, 24}, /* 20 */
1536 {5979, 22, 24}, /* 21 */
1537 {6483, 23, 23}, /* 22 */
1538 {7009, 24, 23}, /* 23 */
1539 {7558, 25, 22}, /* 24 */
1540 {8130, 26, 22}, /* 25 */
1541 {8726, 27, 22}, /* 26 */
1542 {9346, 28, 21}, /* 27 */
1543 {9991, 29, 21}, /* 28 */
1544 {10661, 30, 21}, /* 29 */
1545 {11358, 31, 20}, /* 30 */
1546 {12082, 32, 20}, /* 31 */
1547 {12834, 33, 20}, /* 32 */
1548 {13614, 34, 19}, /* 33 */
1549 {14424, 35, 19}, /* 34 */
1550 {15265, 36, 19}, /* 35 */
1551 {16137, 37, 19}, /* 36 */
1552 {17042, 38, 18}, /* 37 */
1553 {17981, 39, 18}, /* 38 */
1554 {18955, 40, 18}, /* 39 */
1555 {19965, 41, 17}, /* 40 */
1556 {21013, 42, 17}, /* 41 */
1557 {22101, 43, 17}, /* 42 */
1558 {23230, 44, 17}, /* 43 */
1559 {24402, 45, 16}, /* 44 */
1560 {25618, 46, 16}, /* 45 */
1561 {26881, 47, 16}, /* 46 */
1562 {28193, 48, 16}, /* 47 */
1563 {29557, 49, 15}, /* 48 */
1564 {30975, 50, 15}, /* 49 */
1565 {32450, 51, 15}, /* 50 */
1566 {33986, 52, 15}, /* 51 */
1567 {35586, 53, 14}, /* 52 */
1568 {37253, 54, 14}, /* 53 */
1569 {38992, 55, 14}, /* 54 */
1570 {40808, 56, 14}, /* 55 */
1571 {42707, 57, 13}, /* 56 */
1572 {44694, 58, 13}, /* 57 */
1573 {46776, 59, 13}, /* 58 */
1574 {48961, 60, 13}, /* 59 */
1575 {51258, 61, 13}, /* 60 */
1576 {53677, 62, 12}, /* 61 */
1577 {56230, 63, 12}, /* 62 */
1578 {58932, 64, 12}, /* 63 */
1579 {61799, 65, 12}, /* 64 */
1580 {64851, 66, 11}, /* 65 */
1581 {68113, 67, 11}, /* 66 */
1582 {71617, 68, 11}, /* 67 */
1583 {75401, 69, 10}, /* 68 */
1584 {79517, 70, 10}, /* 69 */
1585 {84035, 71, 10}, /* 70 */
1586 {89053, 72, 10}, /* 71 */
1587 {94717, 73, 9} /* 72 */
1588 };
1589
1590 static void
1591 sctp_hs_cwnd_increase(struct sctp_tcb *stcb, struct sctp_nets *net)
1592 {
1593 int cur_val, i, indx, incr;
1594
1595 cur_val = net->cwnd >> 10;
1596 indx = SCTP_HS_TABLE_SIZE - 1;
1597 #ifdef SCTP_DEBUG
1598 printf("HS CC CAlled.\n");
1599 #endif
1600 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
1601 /* normal mode */
1602 if (net->net_ack > net->mtu) {
1603 net->cwnd += net->mtu;
1604 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1605 sctp_log_cwnd(stcb, net, net->mtu, SCTP_CWND_LOG_FROM_SS);
1606 }
1607 } else {
1608 net->cwnd += net->net_ack;
1609 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1610 sctp_log_cwnd(stcb, net, net->net_ack, SCTP_CWND_LOG_FROM_SS);
1611 }
1612 }
1613 } else {
1614 for (i = net->last_hs_used; i < SCTP_HS_TABLE_SIZE; i++) {
1615 if (cur_val < sctp_cwnd_adjust[i].cwnd) {
1616 indx = i;
1617 break;
1618 }
1619 }
1620 net->last_hs_used = indx;
1621 incr = ((sctp_cwnd_adjust[indx].increase) << 10);
1622 net->cwnd += incr;
1623 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1624 sctp_log_cwnd(stcb, net, incr, SCTP_CWND_LOG_FROM_SS);
1625 }
1626 }
1627 }
1628
1629 static void
1630 sctp_hs_cwnd_decrease(struct sctp_tcb *stcb, struct sctp_nets *net)
1631 {
1632 int cur_val, i, indx;
1633 int old_cwnd = net->cwnd;
1634
1635 cur_val = net->cwnd >> 10;
1636 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
1637 /* normal mode */
1638 net->ssthresh = net->cwnd / 2;
1639 if (net->ssthresh < (net->mtu * 2)) {
1640 net->ssthresh = 2 * net->mtu;
1641 }
1642 net->cwnd = net->ssthresh;
1643 } else {
1644 /* drop by the proper amount */
1645 net->ssthresh = net->cwnd - (int)((net->cwnd / 100) *
1646 sctp_cwnd_adjust[net->last_hs_used].drop_percent);
1647 net->cwnd = net->ssthresh;
1648 /* now where are we */
1649 indx = net->last_hs_used;
1650 cur_val = net->cwnd >> 10;
1651 /* reset where we are in the table */
1652 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
1653 /* feel out of hs */
1654 net->last_hs_used = 0;
1655 } else {
1656 for (i = indx; i >= 1; i--) {
1657 if (cur_val > sctp_cwnd_adjust[i - 1].cwnd) {
1658 break;
1659 }
1660 }
1661 net->last_hs_used = indx;
1662 }
1663 }
1664 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1665 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_FR);
1666 }
1667 }
1668
1669 static void
1670 sctp_hs_cwnd_update_after_fr(struct sctp_tcb *stcb,
1671 struct sctp_association *asoc)
1672 {
1673 struct sctp_nets *net;
1674
1675 /*
1676 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) &&
1677 * (net->fast_retran_loss_recovery == 0)))
1678 */
1679 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
1680 if ((asoc->fast_retran_loss_recovery == 0) ||
1681 (asoc->sctp_cmt_on_off > 0)) {
1682 /* out of a RFC2582 Fast recovery window? */
1683 if (net->net_ack > 0) {
1684 /*
1685 * per section 7.2.3, are there any
1686 * destinations that had a fast retransmit
1687 * to them. If so what we need to do is
1688 * adjust ssthresh and cwnd.
1689 */
1690 struct sctp_tmit_chunk *lchk;
1691
1692 sctp_hs_cwnd_decrease(stcb, net);
1693
1694 lchk = TAILQ_FIRST(&asoc->send_queue);
1695
1696 net->partial_bytes_acked = 0;
1697 /* Turn on fast recovery window */
1698 asoc->fast_retran_loss_recovery = 1;
1699 if (lchk == NULL) {
1700 /* Mark end of the window */
1701 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
1702 } else {
1703 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
1704 }
1705
1706 /*
1707 * CMT fast recovery -- per destination
1708 * recovery variable.
1709 */
1710 net->fast_retran_loss_recovery = 1;
1711
1712 if (lchk == NULL) {
1713 /* Mark end of the window */
1714 net->fast_recovery_tsn = asoc->sending_seq - 1;
1715 } else {
1716 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
1717 }
1718
1719 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
1720 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
1721 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
1722 stcb->sctp_ep, stcb, net);
1723 }
1724 } else if (net->net_ack > 0) {
1725 /*
1726 * Mark a peg that we WOULD have done a cwnd
1727 * reduction but RFC2582 prevented this action.
1728 */
1729 SCTP_STAT_INCR(sctps_fastretransinrtt);
1730 }
1731 }
1732 }
1733
1734 static void
1735 sctp_hs_cwnd_update_after_sack(struct sctp_tcb *stcb,
1736 struct sctp_association *asoc,
1737 int accum_moved, int reneged_all SCTP_UNUSED, int will_exit)
1738 {
1739 struct sctp_nets *net;
1740
1741 /******************************/
1742 /* update cwnd and Early FR */
1743 /******************************/
1744 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
1745
1746 #ifdef JANA_CMT_FAST_RECOVERY
1747 /*
1748 * CMT fast recovery code. Need to debug.
1749 */
1750 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
1751 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) ||
1752 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) {
1753 net->will_exit_fast_recovery = 1;
1754 }
1755 }
1756 #endif
1757 /* if nothing was acked on this destination skip it */
1758 if (net->net_ack == 0) {
1759 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1760 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
1761 }
1762 continue;
1763 }
1764 #ifdef JANA_CMT_FAST_RECOVERY
1765 /*
1766 * CMT fast recovery code
1767 */
1768 /*
1769 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery
1770 * && net->will_exit_fast_recovery == 0) { @@@ Do something
1771 * } else if (sctp_cmt_on_off == 0 &&
1772 * asoc->fast_retran_loss_recovery && will_exit == 0) {
1773 */
1774 #endif
1775
1776 if (asoc->fast_retran_loss_recovery &&
1777 (will_exit == 0) &&
1778 (asoc->sctp_cmt_on_off == 0)) {
1779 /*
1780 * If we are in loss recovery we skip any cwnd
1781 * update
1782 */
1783 return;
1784 }
1785 /*
1786 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
1787 * moved.
1788 */
1789 if (accum_moved ||
1790 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) {
1791 /* If the cumulative ack moved we can proceed */
1792 if (net->cwnd <= net->ssthresh) {
1793 /* We are in slow start */
1794 if (net->flight_size + net->net_ack >= net->cwnd) {
1795
1796 sctp_hs_cwnd_increase(stcb, net);
1797
1798 } else {
1799 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1800 sctp_log_cwnd(stcb, net, net->net_ack,
1801 SCTP_CWND_LOG_NOADV_SS);
1802 }
1803 }
1804 } else {
1805 /* We are in congestion avoidance */
1806 net->partial_bytes_acked += net->net_ack;
1807 if ((net->flight_size + net->net_ack >= net->cwnd) &&
1808 (net->partial_bytes_acked >= net->cwnd)) {
1809 net->partial_bytes_acked -= net->cwnd;
1810 net->cwnd += net->mtu;
1811 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1812 sctp_log_cwnd(stcb, net, net->mtu,
1813 SCTP_CWND_LOG_FROM_CA);
1814 }
1815 } else {
1816 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1817 sctp_log_cwnd(stcb, net, net->net_ack,
1818 SCTP_CWND_LOG_NOADV_CA);
1819 }
1820 }
1821 }
1822 } else {
1823 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1824 sctp_log_cwnd(stcb, net, net->mtu,
1825 SCTP_CWND_LOG_NO_CUMACK);
1826 }
1827 }
1828 }
1829 }
1830
1831
1832 /*
1833 * H-TCP congestion control. The algorithm is detailed in:
1834 * R.N.Shorten, D.J.Leith:
1835 * "H-TCP: TCP for high-speed and long-distance networks"
1836 * Proc. PFLDnet, Argonne, 2004.
1837 * http://www.hamilton.ie/net/htcp3.pdf
1838 */
1839
1840
1841 static int use_rtt_scaling = 1;
1842 static int use_bandwidth_switch = 1;
1843
1844 static inline int
1845 between(uint32_t seq1, uint32_t seq2, uint32_t seq3)
1846 {
1847 return (seq3 - seq2 >= seq1 - seq2);
1848 }
1849
1850 static inline uint32_t
1851 htcp_cong_time(struct htcp *ca)
1852 {
1853 return (sctp_get_tick_count() - ca->last_cong);
1854 }
1855
1856 static inline uint32_t
1857 htcp_ccount(struct htcp *ca)
1858 {
1859 return (htcp_cong_time(ca) / ca->minRTT);
1860 }
1861
1862 static inline void
1863 htcp_reset(struct htcp *ca)
1864 {
1865 ca->undo_last_cong = ca->last_cong;
1866 ca->undo_maxRTT = ca->maxRTT;
1867 ca->undo_old_maxB = ca->old_maxB;
1868 ca->last_cong = sctp_get_tick_count();
1869 }
1870
1871 #ifdef SCTP_NOT_USED
1872
1873 static uint32_t
1874 htcp_cwnd_undo(struct sctp_tcb *stcb, struct sctp_nets *net)
1875 {
1876 net->cc_mod.htcp_ca.last_cong = net->cc_mod.htcp_ca.undo_last_cong;
1877 net->cc_mod.htcp_ca.maxRTT = net->cc_mod.htcp_ca.undo_maxRTT;
1878 net->cc_mod.htcp_ca.old_maxB = net->cc_mod.htcp_ca.undo_old_maxB;
1879 return (max(net->cwnd, ((net->ssthresh / net->mtu << 7) / net->cc_mod.htcp_ca.beta) * net->mtu));
1880 }
1881
1882 #endif
1883
1884 static inline void
1885 measure_rtt(struct sctp_nets *net)
1886 {
1887 uint32_t srtt = net->lastsa >> SCTP_RTT_SHIFT;
1888
1889 /* keep track of minimum RTT seen so far, minRTT is zero at first */
1890 if (net->cc_mod.htcp_ca.minRTT > srtt || !net->cc_mod.htcp_ca.minRTT)
1891 net->cc_mod.htcp_ca.minRTT = srtt;
1892
1893 /* max RTT */
1894 if (net->fast_retran_ip == 0 && net->ssthresh < 0xFFFF && htcp_ccount(&net->cc_mod.htcp_ca) > 3) {
1895 if (net->cc_mod.htcp_ca.maxRTT < net->cc_mod.htcp_ca.minRTT)
1896 net->cc_mod.htcp_ca.maxRTT = net->cc_mod.htcp_ca.minRTT;
1897 if (net->cc_mod.htcp_ca.maxRTT < srtt && srtt <= net->cc_mod.htcp_ca.maxRTT + MSEC_TO_TICKS(20))
1898 net->cc_mod.htcp_ca.maxRTT = srtt;
1899 }
1900 }
1901
1902 static void
1903 measure_achieved_throughput(struct sctp_nets *net)
1904 {
1905 uint32_t now = sctp_get_tick_count();
1906
1907 if (net->fast_retran_ip == 0)
1908 net->cc_mod.htcp_ca.bytes_acked = net->net_ack;
1909
1910 if (!use_bandwidth_switch)
1911 return;
1912
1913 /* achieved throughput calculations */
1914 /* JRS - not 100% sure of this statement */
1915 if (net->fast_retran_ip == 1) {
1916 net->cc_mod.htcp_ca.bytecount = 0;
1917 net->cc_mod.htcp_ca.lasttime = now;
1918 return;
1919 }
1920 net->cc_mod.htcp_ca.bytecount += net->net_ack;
1921
1922 if (net->cc_mod.htcp_ca.bytecount >= net->cwnd - ((net->cc_mod.htcp_ca.alpha >> 7 ? : 1) * net->mtu)
1923 && now - net->cc_mod.htcp_ca.lasttime >= net->cc_mod.htcp_ca.minRTT
1924 && net->cc_mod.htcp_ca.minRTT > 0) {
1925 uint32_t cur_Bi = net->cc_mod.htcp_ca.bytecount / net->mtu * hz / (now - net->cc_mod.htcp_ca.lasttime);
1926
1927 if (htcp_ccount(&net->cc_mod.htcp_ca) <= 3) {
1928 /* just after backoff */
1929 net->cc_mod.htcp_ca.minB = net->cc_mod.htcp_ca.maxB = net->cc_mod.htcp_ca.Bi = cur_Bi;
1930 } else {
1931 net->cc_mod.htcp_ca.Bi = (3 * net->cc_mod.htcp_ca.Bi + cur_Bi) / 4;
1932 if (net->cc_mod.htcp_ca.Bi > net->cc_mod.htcp_ca.maxB)
1933 net->cc_mod.htcp_ca.maxB = net->cc_mod.htcp_ca.Bi;
1934 if (net->cc_mod.htcp_ca.minB > net->cc_mod.htcp_ca.maxB)
1935 net->cc_mod.htcp_ca.minB = net->cc_mod.htcp_ca.maxB;
1936 }
1937 net->cc_mod.htcp_ca.bytecount = 0;
1938 net->cc_mod.htcp_ca.lasttime = now;
1939 }
1940 }
1941
1942 static inline void
1943 htcp_beta_update(struct htcp *ca, uint32_t minRTT, uint32_t maxRTT)
1944 {
1945 if (use_bandwidth_switch) {
1946 uint32_t maxB = ca->maxB;
1947 uint32_t old_maxB = ca->old_maxB;
1948
1949 ca->old_maxB = ca->maxB;
1950
1951 if (!between(5 * maxB, 4 * old_maxB, 6 * old_maxB)) {
1952 ca->beta = BETA_MIN;
1953 ca->modeswitch = 0;
1954 return;
1955 }
1956 }
1957 if (ca->modeswitch && minRTT > (uint32_t) MSEC_TO_TICKS(10) && maxRTT) {
1958 ca->beta = (minRTT << 7) / maxRTT;
1959 if (ca->beta < BETA_MIN)
1960 ca->beta = BETA_MIN;
1961 else if (ca->beta > BETA_MAX)
1962 ca->beta = BETA_MAX;
1963 } else {
1964 ca->beta = BETA_MIN;
1965 ca->modeswitch = 1;
1966 }
1967 }
1968
1969 static inline void
1970 htcp_alpha_update(struct htcp *ca)
1971 {
1972 uint32_t minRTT = ca->minRTT;
1973 uint32_t factor = 1;
1974 uint32_t diff = htcp_cong_time(ca);
1975
1976 if (diff > (uint32_t) hz) {
1977 diff -= hz;
1978 factor = 1 + (10 * diff + ((diff / 2) * (diff / 2) / hz)) / hz;
1979 }
1980 if (use_rtt_scaling && minRTT) {
1981 uint32_t scale = (hz << 3) / (10 * minRTT);
1982
1983 scale = min(max(scale, 1U << 2), 10U << 3); /* clamping ratio to
1984 * interval [0.5,10]<<3 */
1985 factor = (factor << 3) / scale;
1986 if (!factor)
1987 factor = 1;
1988 }
1989 ca->alpha = 2 * factor * ((1 << 7) - ca->beta);
1990 if (!ca->alpha)
1991 ca->alpha = ALPHA_BASE;
1992 }
1993
1994 /* After we have the rtt data to calculate beta, we'd still prefer to wait one
1995 * rtt before we adjust our beta to ensure we are working from a consistent
1996 * data.
1997 *
1998 * This function should be called when we hit a congestion event since only at
1999 * that point do we really have a real sense of maxRTT (the queues en route
2000 * were getting just too full now).
2001 */
2002 static void
2003 htcp_param_update(struct sctp_nets *net)
2004 {
2005 uint32_t minRTT = net->cc_mod.htcp_ca.minRTT;
2006 uint32_t maxRTT = net->cc_mod.htcp_ca.maxRTT;
2007
2008 htcp_beta_update(&net->cc_mod.htcp_ca, minRTT, maxRTT);
2009 htcp_alpha_update(&net->cc_mod.htcp_ca);
2010
2011 /*
2012 * add slowly fading memory for maxRTT to accommodate routing
2013 * changes etc
2014 */
2015 if (minRTT > 0 && maxRTT > minRTT)
2016 net->cc_mod.htcp_ca.maxRTT = minRTT + ((maxRTT - minRTT) * 95) / 100;
2017 }
2018
2019 static uint32_t
2020 htcp_recalc_ssthresh(struct sctp_nets *net)
2021 {
2022 htcp_param_update(net);
2023 return (max(((net->cwnd / net->mtu * net->cc_mod.htcp_ca.beta) >> 7) * net->mtu, 2U * net->mtu));
2024 }
2025
2026 static void
2027 htcp_cong_avoid(struct sctp_tcb *stcb, struct sctp_nets *net)
2028 {
2029 /*-
2030 * How to handle these functions?
2031 * if (!tcp_is_cwnd_limited(sk, in_flight)) RRS - good question.
2032 * return;
2033 */
2034 if (net->cwnd <= net->ssthresh) {
2035 /* We are in slow start */
2036 if (net->flight_size + net->net_ack >= net->cwnd) {
2037 if (net->net_ack > (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable))) {
2038 net->cwnd += (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable));
2039 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2040 sctp_log_cwnd(stcb, net, net->mtu,
2041 SCTP_CWND_LOG_FROM_SS);
2042 }
2043 } else {
2044 net->cwnd += net->net_ack;
2045 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2046 sctp_log_cwnd(stcb, net, net->net_ack,
2047 SCTP_CWND_LOG_FROM_SS);
2048 }
2049 }
2050 } else {
2051 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
2052 sctp_log_cwnd(stcb, net, net->net_ack,
2053 SCTP_CWND_LOG_NOADV_SS);
2054 }
2055 }
2056 } else {
2057 measure_rtt(net);
2058
2059 /*
2060 * In dangerous area, increase slowly. In theory this is
2061 * net->cwnd += alpha / net->cwnd
2062 */
2063 /* What is snd_cwnd_cnt?? */
2064 if (((net->partial_bytes_acked / net->mtu * net->cc_mod.htcp_ca.alpha) >> 7) * net->mtu >= net->cwnd) {
2065 /*-
2066 * Does SCTP have a cwnd clamp?
2067 * if (net->snd_cwnd < net->snd_cwnd_clamp) - Nope (RRS).
2068 */
2069 net->cwnd += net->mtu;
2070 net->partial_bytes_acked = 0;
2071 htcp_alpha_update(&net->cc_mod.htcp_ca);
2072 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2073 sctp_log_cwnd(stcb, net, net->mtu,
2074 SCTP_CWND_LOG_FROM_CA);
2075 }
2076 } else {
2077 net->partial_bytes_acked += net->net_ack;
2078 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
2079 sctp_log_cwnd(stcb, net, net->net_ack,
2080 SCTP_CWND_LOG_NOADV_CA);
2081 }
2082 }
2083
2084 net->cc_mod.htcp_ca.bytes_acked = net->mtu;
2085 }
2086 }
2087
2088 #ifdef SCTP_NOT_USED
2089 /* Lower bound on congestion window. */
2090 static uint32_t
2091 htcp_min_cwnd(struct sctp_tcb *stcb, struct sctp_nets *net)
2092 {
2093 return (net->ssthresh);
2094 }
2095
2096 #endif
2097
2098 static void
2099 htcp_init(struct sctp_nets *net)
2100 {
2101 memset(&net->cc_mod.htcp_ca, 0, sizeof(struct htcp));
2102 net->cc_mod.htcp_ca.alpha = ALPHA_BASE;
2103 net->cc_mod.htcp_ca.beta = BETA_MIN;
2104 net->cc_mod.htcp_ca.bytes_acked = net->mtu;
2105 net->cc_mod.htcp_ca.last_cong = sctp_get_tick_count();
2106 }
2107
2108 static void
2109 sctp_htcp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net)
2110 {
2111 /*
2112 * We take the max of the burst limit times a MTU or the
2113 * INITIAL_CWND. We then limit this to 4 MTU's of sending.
2114 */
2115 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
2116 net->ssthresh = stcb->asoc.peers_rwnd;
2117 htcp_init(net);
2118
2119 if (SCTP_BASE_SYSCTL(sctp_logging_level) & (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) {
2120 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION);
2121 }
2122 }
2123
2124 static void
2125 sctp_htcp_cwnd_update_after_sack(struct sctp_tcb *stcb,
2126 struct sctp_association *asoc,
2127 int accum_moved, int reneged_all SCTP_UNUSED, int will_exit)
2128 {
2129 struct sctp_nets *net;
2130
2131 /******************************/
2132 /* update cwnd and Early FR */
2133 /******************************/
2134 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
2135
2136 #ifdef JANA_CMT_FAST_RECOVERY
2137 /*
2138 * CMT fast recovery code. Need to debug.
2139 */
2140 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
2141 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) ||
2142 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) {
2143 net->will_exit_fast_recovery = 1;
2144 }
2145 }
2146 #endif
2147 /* if nothing was acked on this destination skip it */
2148 if (net->net_ack == 0) {
2149 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
2150 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
2151 }
2152 continue;
2153 }
2154 #ifdef JANA_CMT_FAST_RECOVERY
2155 /*
2156 * CMT fast recovery code
2157 */
2158 /*
2159 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery
2160 * && net->will_exit_fast_recovery == 0) { @@@ Do something
2161 * } else if (sctp_cmt_on_off == 0 &&
2162 * asoc->fast_retran_loss_recovery && will_exit == 0) {
2163 */
2164 #endif
2165
2166 if (asoc->fast_retran_loss_recovery &&
2167 will_exit == 0 &&
2168 (asoc->sctp_cmt_on_off == 0)) {
2169 /*
2170 * If we are in loss recovery we skip any cwnd
2171 * update
2172 */
2173 return;
2174 }
2175 /*
2176 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
2177 * moved.
2178 */
2179 if (accum_moved ||
2180 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) {
2181 htcp_cong_avoid(stcb, net);
2182 measure_achieved_throughput(net);
2183 } else {
2184 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
2185 sctp_log_cwnd(stcb, net, net->mtu,
2186 SCTP_CWND_LOG_NO_CUMACK);
2187 }
2188 }
2189 }
2190 }
2191
2192 static void
2193 sctp_htcp_cwnd_update_after_fr(struct sctp_tcb *stcb,
2194 struct sctp_association *asoc)
2195 {
2196 struct sctp_nets *net;
2197
2198 /*
2199 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) &&
2200 * (net->fast_retran_loss_recovery == 0)))
2201 */
2202 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
2203 if ((asoc->fast_retran_loss_recovery == 0) ||
2204 (asoc->sctp_cmt_on_off > 0)) {
2205 /* out of a RFC2582 Fast recovery window? */
2206 if (net->net_ack > 0) {
2207 /*
2208 * per section 7.2.3, are there any
2209 * destinations that had a fast retransmit
2210 * to them. If so what we need to do is
2211 * adjust ssthresh and cwnd.
2212 */
2213 struct sctp_tmit_chunk *lchk;
2214 int old_cwnd = net->cwnd;
2215
2216 /* JRS - reset as if state were changed */
2217 htcp_reset(&net->cc_mod.htcp_ca);
2218 net->ssthresh = htcp_recalc_ssthresh(net);
2219 net->cwnd = net->ssthresh;
2220 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2221 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
2222 SCTP_CWND_LOG_FROM_FR);
2223 }
2224 lchk = TAILQ_FIRST(&asoc->send_queue);
2225
2226 net->partial_bytes_acked = 0;
2227 /* Turn on fast recovery window */
2228 asoc->fast_retran_loss_recovery = 1;
2229 if (lchk == NULL) {
2230 /* Mark end of the window */
2231 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
2232 } else {
2233 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
2234 }
2235
2236 /*
2237 * CMT fast recovery -- per destination
2238 * recovery variable.
2239 */
2240 net->fast_retran_loss_recovery = 1;
2241
2242 if (lchk == NULL) {
2243 /* Mark end of the window */
2244 net->fast_recovery_tsn = asoc->sending_seq - 1;
2245 } else {
2246 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
2247 }
2248
2249 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
2250 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
2251 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
2252 stcb->sctp_ep, stcb, net);
2253 }
2254 } else if (net->net_ack > 0) {
2255 /*
2256 * Mark a peg that we WOULD have done a cwnd
2257 * reduction but RFC2582 prevented this action.
2258 */
2259 SCTP_STAT_INCR(sctps_fastretransinrtt);
2260 }
2261 }
2262 }
2263
2264 static void
2265 sctp_htcp_cwnd_update_after_timeout(struct sctp_tcb *stcb,
2266 struct sctp_nets *net)
2267 {
2268 int old_cwnd = net->cwnd;
2269
2270 /* JRS - reset as if the state were being changed to timeout */
2271 htcp_reset(&net->cc_mod.htcp_ca);
2272 net->ssthresh = htcp_recalc_ssthresh(net);
2273 net->cwnd = net->mtu;
2274 net->partial_bytes_acked = 0;
2275 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2276 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX);
2277 }
2278 }
2279
2280 static void
2281 sctp_htcp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb,
2282 struct sctp_nets *net, int in_window, int num_pkt_lost SCTP_UNUSED)
2283 {
2284 int old_cwnd;
2285
2286 old_cwnd = net->cwnd;
2287
2288 /* JRS - reset hctp as if state changed */
2289 if (in_window == 0) {
2290 htcp_reset(&net->cc_mod.htcp_ca);
2291 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
2292 net->ssthresh = htcp_recalc_ssthresh(net);
2293 if (net->ssthresh < net->mtu) {
2294 net->ssthresh = net->mtu;
2295 /* here back off the timer as well, to slow us down */
2296 net->RTO <<= 1;
2297 }
2298 net->cwnd = net->ssthresh;
2299 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2300 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
2301 }
2302 }
2303 }
2304
2305 struct sctp_cc_functions sctp_cc_functions[] = {
2306 {
2307 .sctp_set_initial_cc_param = sctp_set_initial_cc_param,
2308 .sctp_cwnd_update_after_sack = sctp_cwnd_update_after_sack,
2309 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common,
2310 .sctp_cwnd_update_after_fr = sctp_cwnd_update_after_fr,
2311 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout,
2312 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_after_ecn_echo,
2313 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped,
2314 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output,
2315 },
2316 {
2317 .sctp_set_initial_cc_param = sctp_set_initial_cc_param,
2318 .sctp_cwnd_update_after_sack = sctp_hs_cwnd_update_after_sack,
2319 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common,
2320 .sctp_cwnd_update_after_fr = sctp_hs_cwnd_update_after_fr,
2321 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout,
2322 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_after_ecn_echo,
2323 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped,
2324 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output,
2325 },
2326 {
2327 .sctp_set_initial_cc_param = sctp_htcp_set_initial_cc_param,
2328 .sctp_cwnd_update_after_sack = sctp_htcp_cwnd_update_after_sack,
2329 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common,
2330 .sctp_cwnd_update_after_fr = sctp_htcp_cwnd_update_after_fr,
2331 .sctp_cwnd_update_after_timeout = sctp_htcp_cwnd_update_after_timeout,
2332 .sctp_cwnd_update_after_ecn_echo = sctp_htcp_cwnd_update_after_ecn_echo,
2333 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped,
2334 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output,
2335 },
2336 {
2337 .sctp_set_initial_cc_param = sctp_set_rtcc_initial_cc_param,
2338 .sctp_cwnd_update_after_sack = sctp_cwnd_update_rtcc_after_sack,
2339 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common,
2340 .sctp_cwnd_update_after_fr = sctp_cwnd_update_after_fr,
2341 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout,
2342 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_rtcc_after_ecn_echo,
2343 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped,
2344 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output,
2345 .sctp_cwnd_update_packet_transmitted = sctp_cwnd_update_rtcc_packet_transmitted,
2346 .sctp_cwnd_update_tsn_acknowledged = sctp_cwnd_update_rtcc_tsn_acknowledged,
2347 .sctp_cwnd_new_transmission_begins = sctp_cwnd_new_rtcc_transmission_begins,
2348 .sctp_cwnd_prepare_net_for_sack = sctp_cwnd_prepare_rtcc_net_for_sack,
2349 .sctp_cwnd_socket_option = sctp_cwnd_rtcc_socket_option,
2350 .sctp_rtt_calculated = sctp_rtt_rtcc_calculated
2351 }
2352 };
Cache object: cea768cd2d2eb7a873a942e0d8280ebe
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