1 /*-
2 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
3 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
4 * Copyright (c) 2008-2012, 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 <sys/cdefs.h>
34 __FBSDID("$FreeBSD: releng/8.4/sys/netinet/sctp_cc_functions.c 247987 2013-03-08 00:05:15Z tuexen $");
35
36 #include <netinet/sctp_os.h>
37 #include <netinet/sctp_var.h>
38 #include <netinet/sctp_sysctl.h>
39 #include <netinet/sctp_pcb.h>
40 #include <netinet/sctp_header.h>
41 #include <netinet/sctputil.h>
42 #include <netinet/sctp_output.h>
43 #include <netinet/sctp_input.h>
44 #include <netinet/sctp_indata.h>
45 #include <netinet/sctp_uio.h>
46 #include <netinet/sctp_timer.h>
47 #include <netinet/sctp_auth.h>
48 #include <netinet/sctp_asconf.h>
49 #include <netinet/sctp_dtrace_declare.h>
50
51 #define SHIFT_MPTCP_MULTI_N 40
52 #define SHIFT_MPTCP_MULTI_Z 16
53 #define SHIFT_MPTCP_MULTI 8
54
55 static void
56 sctp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net)
57 {
58 struct sctp_association *assoc;
59 uint32_t cwnd_in_mtu;
60
61 assoc = &stcb->asoc;
62 cwnd_in_mtu = SCTP_BASE_SYSCTL(sctp_initial_cwnd);
63 if (cwnd_in_mtu == 0) {
64 /* Using 0 means that the value of RFC 4960 is used. */
65 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
66 } else {
67 /*
68 * We take the minimum of the burst limit and the initial
69 * congestion window.
70 */
71 if ((assoc->max_burst > 0) && (cwnd_in_mtu > assoc->max_burst))
72 cwnd_in_mtu = assoc->max_burst;
73 net->cwnd = (net->mtu - sizeof(struct sctphdr)) * cwnd_in_mtu;
74 }
75 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) ||
76 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2)) {
77 /* In case of resource pooling initialize appropriately */
78 net->cwnd /= assoc->numnets;
79 if (net->cwnd < (net->mtu - sizeof(struct sctphdr))) {
80 net->cwnd = net->mtu - sizeof(struct sctphdr);
81 }
82 }
83 net->ssthresh = assoc->peers_rwnd;
84 SDT_PROBE(sctp, cwnd, net, init,
85 stcb->asoc.my_vtag, ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), net,
86 0, net->cwnd);
87 if (SCTP_BASE_SYSCTL(sctp_logging_level) &
88 (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) {
89 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION);
90 }
91 }
92
93 static void
94 sctp_cwnd_update_after_fr(struct sctp_tcb *stcb,
95 struct sctp_association *asoc)
96 {
97 struct sctp_nets *net;
98 uint32_t t_ssthresh, t_cwnd;
99 uint64_t t_ucwnd_sbw;
100
101 /* MT FIXME: Don't compute this over and over again */
102 t_ssthresh = 0;
103 t_cwnd = 0;
104 t_ucwnd_sbw = 0;
105 if ((asoc->sctp_cmt_on_off == SCTP_CMT_RPV1) ||
106 (asoc->sctp_cmt_on_off == SCTP_CMT_RPV2)) {
107 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
108 t_ssthresh += net->ssthresh;
109 t_cwnd += net->cwnd;
110 if (net->lastsa > 0) {
111 t_ucwnd_sbw += (uint64_t) net->cwnd / (uint64_t) net->lastsa;
112 }
113 }
114 if (t_ucwnd_sbw == 0) {
115 t_ucwnd_sbw = 1;
116 }
117 }
118 /*-
119 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) &&
120 * (net->fast_retran_loss_recovery == 0)))
121 */
122 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
123 if ((asoc->fast_retran_loss_recovery == 0) ||
124 (asoc->sctp_cmt_on_off > 0)) {
125 /* out of a RFC2582 Fast recovery window? */
126 if (net->net_ack > 0) {
127 /*
128 * per section 7.2.3, are there any
129 * destinations that had a fast retransmit
130 * to them. If so what we need to do is
131 * adjust ssthresh and cwnd.
132 */
133 struct sctp_tmit_chunk *lchk;
134 int old_cwnd = net->cwnd;
135
136 if ((asoc->sctp_cmt_on_off == SCTP_CMT_RPV1) ||
137 (asoc->sctp_cmt_on_off == SCTP_CMT_RPV2)) {
138 if (asoc->sctp_cmt_on_off == SCTP_CMT_RPV1) {
139 net->ssthresh = (uint32_t) (((uint64_t) 4 *
140 (uint64_t) net->mtu *
141 (uint64_t) net->ssthresh) /
142 (uint64_t) t_ssthresh);
143
144 }
145 if (asoc->sctp_cmt_on_off == SCTP_CMT_RPV2) {
146 uint32_t srtt;
147
148 srtt = net->lastsa;
149 /*
150 * lastsa>>3; we don't need
151 * to devide ...
152 */
153 if (srtt == 0) {
154 srtt = 1;
155 }
156 /*
157 * Short Version => Equal to
158 * Contel Version MBe
159 */
160 net->ssthresh = (uint32_t) (((uint64_t) 4 *
161 (uint64_t) net->mtu *
162 (uint64_t) net->cwnd) /
163 ((uint64_t) srtt *
164 t_ucwnd_sbw));
165 /* INCREASE FACTOR */ ;
166 }
167 if ((net->cwnd > t_cwnd / 2) &&
168 (net->ssthresh < net->cwnd - t_cwnd / 2)) {
169 net->ssthresh = net->cwnd - t_cwnd / 2;
170 }
171 if (net->ssthresh < net->mtu) {
172 net->ssthresh = net->mtu;
173 }
174 } else {
175 net->ssthresh = net->cwnd / 2;
176 if (net->ssthresh < (net->mtu * 2)) {
177 net->ssthresh = 2 * net->mtu;
178 }
179 }
180 net->cwnd = net->ssthresh;
181 SDT_PROBE(sctp, cwnd, net, fr,
182 stcb->asoc.my_vtag, ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), net,
183 old_cwnd, net->cwnd);
184 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
185 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
186 SCTP_CWND_LOG_FROM_FR);
187 }
188 lchk = TAILQ_FIRST(&asoc->send_queue);
189
190 net->partial_bytes_acked = 0;
191 /* Turn on fast recovery window */
192 asoc->fast_retran_loss_recovery = 1;
193 if (lchk == NULL) {
194 /* Mark end of the window */
195 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
196 } else {
197 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
198 }
199
200 /*
201 * CMT fast recovery -- per destination
202 * recovery variable.
203 */
204 net->fast_retran_loss_recovery = 1;
205
206 if (lchk == NULL) {
207 /* Mark end of the window */
208 net->fast_recovery_tsn = asoc->sending_seq - 1;
209 } else {
210 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
211 }
212
213 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
214 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
215 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
216 stcb->sctp_ep, stcb, net);
217 }
218 } else if (net->net_ack > 0) {
219 /*
220 * Mark a peg that we WOULD have done a cwnd
221 * reduction but RFC2582 prevented this action.
222 */
223 SCTP_STAT_INCR(sctps_fastretransinrtt);
224 }
225 }
226 }
227
228 /* Defines for instantaneous bw decisions */
229 #define SCTP_INST_LOOSING 1 /* Loosing to other flows */
230 #define SCTP_INST_NEUTRAL 2 /* Neutral, no indication */
231 #define SCTP_INST_GAINING 3 /* Gaining, step down possible */
232
233
234 static int
235 cc_bw_same(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw,
236 uint64_t rtt_offset, uint64_t vtag, uint8_t inst_ind)
237 {
238 uint64_t oth, probepoint;
239
240 probepoint = (((uint64_t) net->cwnd) << 32);
241 if (net->rtt > net->cc_mod.rtcc.lbw_rtt + rtt_offset) {
242 /*
243 * rtt increased we don't update bw.. so we don't update the
244 * rtt either.
245 */
246 /* Probe point 5 */
247 probepoint |= ((5 << 16) | 1);
248 SDT_PROBE(sctp, cwnd, net, rttvar,
249 vtag,
250 ((net->cc_mod.rtcc.lbw << 32) | nbw),
251 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
252 net->flight_size,
253 probepoint);
254 if ((net->cc_mod.rtcc.steady_step) && (inst_ind != SCTP_INST_LOOSING)) {
255 if (net->cc_mod.rtcc.last_step_state == 5)
256 net->cc_mod.rtcc.step_cnt++;
257 else
258 net->cc_mod.rtcc.step_cnt = 1;
259 net->cc_mod.rtcc.last_step_state = 5;
260 if ((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) &&
262 ((net->cc_mod.rtcc.step_cnt % net->cc_mod.rtcc.steady_step) == 0))) {
263 /* Try a step down */
264 oth = net->cc_mod.rtcc.vol_reduce;
265 oth <<= 16;
266 oth |= net->cc_mod.rtcc.step_cnt;
267 oth <<= 16;
268 oth |= net->cc_mod.rtcc.last_step_state;
269 SDT_PROBE(sctp, cwnd, net, rttstep,
270 vtag,
271 ((net->cc_mod.rtcc.lbw << 32) | nbw),
272 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
273 oth,
274 probepoint);
275 if (net->cwnd > (4 * net->mtu)) {
276 net->cwnd -= net->mtu;
277 net->cc_mod.rtcc.vol_reduce++;
278 } else {
279 net->cc_mod.rtcc.step_cnt = 0;
280 }
281 }
282 }
283 return (1);
284 }
285 if (net->rtt < net->cc_mod.rtcc.lbw_rtt - rtt_offset) {
286 /*
287 * rtt decreased, there could be more room. we update both
288 * the bw and the rtt here to lock this in as a good step
289 * down.
290 */
291 /* Probe point 6 */
292 probepoint |= ((6 << 16) | 0);
293 SDT_PROBE(sctp, cwnd, net, rttvar,
294 vtag,
295 ((net->cc_mod.rtcc.lbw << 32) | nbw),
296 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
297 net->flight_size,
298 probepoint);
299 if (net->cc_mod.rtcc.steady_step) {
300 oth = net->cc_mod.rtcc.vol_reduce;
301 oth <<= 16;
302 oth |= net->cc_mod.rtcc.step_cnt;
303 oth <<= 16;
304 oth |= net->cc_mod.rtcc.last_step_state;
305 SDT_PROBE(sctp, cwnd, net, rttstep,
306 vtag,
307 ((net->cc_mod.rtcc.lbw << 32) | nbw),
308 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
309 oth,
310 probepoint);
311 if ((net->cc_mod.rtcc.last_step_state == 5) &&
312 (net->cc_mod.rtcc.step_cnt > net->cc_mod.rtcc.steady_step)) {
313 /* Step down worked */
314 net->cc_mod.rtcc.step_cnt = 0;
315 return (1);
316 } else {
317 net->cc_mod.rtcc.last_step_state = 6;
318 net->cc_mod.rtcc.step_cnt = 0;
319 }
320 }
321 net->cc_mod.rtcc.lbw = nbw;
322 net->cc_mod.rtcc.lbw_rtt = net->rtt;
323 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd;
324 if (inst_ind == SCTP_INST_GAINING)
325 return (1);
326 else if (inst_ind == SCTP_INST_NEUTRAL)
327 return (1);
328 else
329 return (0);
330 }
331 /*
332 * Ok bw and rtt remained the same .. no update to any
333 */
334 /* Probe point 7 */
335 probepoint |= ((7 << 16) | net->cc_mod.rtcc.ret_from_eq);
336 SDT_PROBE(sctp, cwnd, net, rttvar,
337 vtag,
338 ((net->cc_mod.rtcc.lbw << 32) | nbw),
339 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
340 net->flight_size,
341 probepoint);
342 if ((net->cc_mod.rtcc.steady_step) && (inst_ind != SCTP_INST_LOOSING)) {
343 if (net->cc_mod.rtcc.last_step_state == 5)
344 net->cc_mod.rtcc.step_cnt++;
345 else
346 net->cc_mod.rtcc.step_cnt = 1;
347 net->cc_mod.rtcc.last_step_state = 5;
348 if ((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) &&
350 ((net->cc_mod.rtcc.step_cnt % net->cc_mod.rtcc.steady_step) == 0))) {
351 /* Try a step down */
352 if (net->cwnd > (4 * net->mtu)) {
353 net->cwnd -= net->mtu;
354 net->cc_mod.rtcc.vol_reduce++;
355 return (1);
356 } else {
357 net->cc_mod.rtcc.step_cnt = 0;
358 }
359 }
360 }
361 if (inst_ind == SCTP_INST_GAINING)
362 return (1);
363 else if (inst_ind == SCTP_INST_NEUTRAL)
364 return (1);
365 else
366 return ((int)net->cc_mod.rtcc.ret_from_eq);
367 }
368
369 static int
370 cc_bw_decrease(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw, uint64_t rtt_offset,
371 uint64_t vtag, uint8_t inst_ind)
372 {
373 uint64_t oth, probepoint;
374
375 /* Bandwidth decreased. */
376 probepoint = (((uint64_t) net->cwnd) << 32);
377 if (net->rtt > net->cc_mod.rtcc.lbw_rtt + rtt_offset) {
378 /* rtt increased */
379 /* Did we add more */
380 if ((net->cwnd > net->cc_mod.rtcc.cwnd_at_bw_set) &&
381 (inst_ind != SCTP_INST_LOOSING)) {
382 /* We caused it maybe.. back off? */
383 /* PROBE POINT 1 */
384 probepoint |= ((1 << 16) | 1);
385 SDT_PROBE(sctp, cwnd, net, rttvar,
386 vtag,
387 ((net->cc_mod.rtcc.lbw << 32) | nbw),
388 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
389 net->flight_size,
390 probepoint);
391 if (net->cc_mod.rtcc.ret_from_eq) {
392 /*
393 * Switch over to CA if we are less
394 * aggressive
395 */
396 net->ssthresh = net->cwnd - 1;
397 net->partial_bytes_acked = 0;
398 }
399 return (1);
400 }
401 /* Probe point 2 */
402 probepoint |= ((2 << 16) | 0);
403 SDT_PROBE(sctp, cwnd, net, rttvar,
404 vtag,
405 ((net->cc_mod.rtcc.lbw << 32) | nbw),
406 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
407 net->flight_size,
408 probepoint);
409 /* Someone else - fight for more? */
410 if (net->cc_mod.rtcc.steady_step) {
411 oth = net->cc_mod.rtcc.vol_reduce;
412 oth <<= 16;
413 oth |= net->cc_mod.rtcc.step_cnt;
414 oth <<= 16;
415 oth |= net->cc_mod.rtcc.last_step_state;
416 SDT_PROBE(sctp, cwnd, net, rttstep,
417 vtag,
418 ((net->cc_mod.rtcc.lbw << 32) | nbw),
419 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
420 oth,
421 probepoint);
422 /*
423 * Did we voluntarily give up some? if so take one
424 * back please
425 */
426 if ((net->cc_mod.rtcc.vol_reduce) &&
427 (inst_ind != SCTP_INST_GAINING)) {
428 net->cwnd += net->mtu;
429 net->cc_mod.rtcc.vol_reduce--;
430 }
431 net->cc_mod.rtcc.last_step_state = 2;
432 net->cc_mod.rtcc.step_cnt = 0;
433 }
434 goto out_decision;
435 } else if (net->rtt < net->cc_mod.rtcc.lbw_rtt - rtt_offset) {
436 /* bw & rtt decreased */
437 /* Probe point 3 */
438 probepoint |= ((3 << 16) | 0);
439 SDT_PROBE(sctp, cwnd, net, rttvar,
440 vtag,
441 ((net->cc_mod.rtcc.lbw << 32) | nbw),
442 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
443 net->flight_size,
444 probepoint);
445 if (net->cc_mod.rtcc.steady_step) {
446 oth = net->cc_mod.rtcc.vol_reduce;
447 oth <<= 16;
448 oth |= net->cc_mod.rtcc.step_cnt;
449 oth <<= 16;
450 oth |= net->cc_mod.rtcc.last_step_state;
451 SDT_PROBE(sctp, cwnd, net, rttstep,
452 vtag,
453 ((net->cc_mod.rtcc.lbw << 32) | nbw),
454 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
455 oth,
456 probepoint);
457 if ((net->cc_mod.rtcc.vol_reduce) &&
458 (inst_ind != SCTP_INST_GAINING)) {
459 net->cwnd += net->mtu;
460 net->cc_mod.rtcc.vol_reduce--;
461 }
462 net->cc_mod.rtcc.last_step_state = 3;
463 net->cc_mod.rtcc.step_cnt = 0;
464 }
465 goto out_decision;
466 }
467 /* The bw decreased but rtt stayed the same */
468 /* Probe point 4 */
469 probepoint |= ((4 << 16) | 0);
470 SDT_PROBE(sctp, cwnd, net, rttvar,
471 vtag,
472 ((net->cc_mod.rtcc.lbw << 32) | nbw),
473 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
474 net->flight_size,
475 probepoint);
476 if (net->cc_mod.rtcc.steady_step) {
477 oth = net->cc_mod.rtcc.vol_reduce;
478 oth <<= 16;
479 oth |= net->cc_mod.rtcc.step_cnt;
480 oth <<= 16;
481 oth |= net->cc_mod.rtcc.last_step_state;
482 SDT_PROBE(sctp, cwnd, net, rttstep,
483 vtag,
484 ((net->cc_mod.rtcc.lbw << 32) | nbw),
485 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
486 oth,
487 probepoint);
488 if ((net->cc_mod.rtcc.vol_reduce) &&
489 (inst_ind != SCTP_INST_GAINING)) {
490 net->cwnd += net->mtu;
491 net->cc_mod.rtcc.vol_reduce--;
492 }
493 net->cc_mod.rtcc.last_step_state = 4;
494 net->cc_mod.rtcc.step_cnt = 0;
495 }
496 out_decision:
497 net->cc_mod.rtcc.lbw = nbw;
498 net->cc_mod.rtcc.lbw_rtt = net->rtt;
499 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd;
500 if (inst_ind == SCTP_INST_GAINING) {
501 return (1);
502 } else {
503 return (0);
504 }
505 }
506
507 static int
508 cc_bw_increase(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw, uint64_t vtag)
509 {
510 uint64_t oth, probepoint;
511
512 /*
513 * BW increased, so update and return 0, since all actions in our
514 * table say to do the normal CC update. Note that we pay no
515 * attention to the inst_ind since our overall sum is increasing.
516 */
517 /* PROBE POINT 0 */
518 probepoint = (((uint64_t) net->cwnd) << 32);
519 SDT_PROBE(sctp, cwnd, net, rttvar,
520 vtag,
521 ((net->cc_mod.rtcc.lbw << 32) | nbw),
522 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
523 net->flight_size,
524 probepoint);
525 if (net->cc_mod.rtcc.steady_step) {
526 oth = net->cc_mod.rtcc.vol_reduce;
527 oth <<= 16;
528 oth |= net->cc_mod.rtcc.step_cnt;
529 oth <<= 16;
530 oth |= net->cc_mod.rtcc.last_step_state;
531 SDT_PROBE(sctp, cwnd, net, rttstep,
532 vtag,
533 ((net->cc_mod.rtcc.lbw << 32) | nbw),
534 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
535 oth,
536 probepoint);
537 net->cc_mod.rtcc.last_step_state = 0;
538 net->cc_mod.rtcc.step_cnt = 0;
539 net->cc_mod.rtcc.vol_reduce = 0;
540 }
541 net->cc_mod.rtcc.lbw = nbw;
542 net->cc_mod.rtcc.lbw_rtt = net->rtt;
543 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd;
544 return (0);
545 }
546
547 /* RTCC Algoritm to limit growth of cwnd, return
548 * true if you want to NOT allow cwnd growth
549 */
550 static int
551 cc_bw_limit(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw)
552 {
553 uint64_t bw_offset, rtt_offset;
554 uint64_t probepoint, rtt, vtag;
555 uint64_t bytes_for_this_rtt, inst_bw;
556 uint64_t div, inst_off;
557 int bw_shift;
558 uint8_t inst_ind;
559 int ret;
560
561 /*-
562 * Here we need to see if we want
563 * to limit cwnd growth due to increase
564 * in overall rtt but no increase in bw.
565 * We use the following table to figure
566 * out what we should do. When we return
567 * 0, cc update goes on as planned. If we
568 * return 1, then no cc update happens and cwnd
569 * stays where it is at.
570 * ----------------------------------
571 * BW | RTT | Action
572 * *********************************
573 * INC | INC | return 0
574 * ----------------------------------
575 * INC | SAME | return 0
576 * ----------------------------------
577 * INC | DECR | return 0
578 * ----------------------------------
579 * SAME | INC | return 1
580 * ----------------------------------
581 * SAME | SAME | return 1
582 * ----------------------------------
583 * SAME | DECR | return 0
584 * ----------------------------------
585 * DECR | INC | return 0 or 1 based on if we caused.
586 * ----------------------------------
587 * DECR | SAME | return 0
588 * ----------------------------------
589 * DECR | DECR | return 0
590 * ----------------------------------
591 *
592 * We are a bit fuzz on what an increase or
593 * decrease is. For BW it is the same if
594 * it did not change within 1/64th. For
595 * RTT it stayed the same if it did not
596 * change within 1/32nd
597 */
598 bw_shift = SCTP_BASE_SYSCTL(sctp_rttvar_bw);
599 rtt = stcb->asoc.my_vtag;
600 vtag = (rtt << 32) | (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) | (stcb->rport);
601 probepoint = (((uint64_t) net->cwnd) << 32);
602 rtt = net->rtt;
603 if (net->cc_mod.rtcc.rtt_set_this_sack) {
604 net->cc_mod.rtcc.rtt_set_this_sack = 0;
605 bytes_for_this_rtt = net->cc_mod.rtcc.bw_bytes - net->cc_mod.rtcc.bw_bytes_at_last_rttc;
606 net->cc_mod.rtcc.bw_bytes_at_last_rttc = net->cc_mod.rtcc.bw_bytes;
607 if (net->rtt) {
608 div = net->rtt / 1000;
609 if (div) {
610 inst_bw = bytes_for_this_rtt / div;
611 inst_off = inst_bw >> bw_shift;
612 if (inst_bw > nbw)
613 inst_ind = SCTP_INST_GAINING;
614 else if ((inst_bw + inst_off) < nbw)
615 inst_ind = SCTP_INST_LOOSING;
616 else
617 inst_ind = SCTP_INST_NEUTRAL;
618 probepoint |= ((0xb << 16) | inst_ind);
619 } else {
620 inst_ind = net->cc_mod.rtcc.last_inst_ind;
621 inst_bw = bytes_for_this_rtt / (uint64_t) (net->rtt);
622 /* Can't determine do not change */
623 probepoint |= ((0xc << 16) | inst_ind);
624 }
625 } else {
626 inst_ind = net->cc_mod.rtcc.last_inst_ind;
627 inst_bw = bytes_for_this_rtt;
628 /* Can't determine do not change */
629 probepoint |= ((0xd << 16) | inst_ind);
630 }
631 SDT_PROBE(sctp, cwnd, net, rttvar,
632 vtag,
633 ((nbw << 32) | inst_bw),
634 ((net->cc_mod.rtcc.lbw_rtt << 32) | rtt),
635 net->flight_size,
636 probepoint);
637 } else {
638 /* No rtt measurement, use last one */
639 inst_ind = net->cc_mod.rtcc.last_inst_ind;
640 }
641 bw_offset = net->cc_mod.rtcc.lbw >> bw_shift;
642 if (nbw > net->cc_mod.rtcc.lbw + bw_offset) {
643 ret = cc_bw_increase(stcb, net, nbw, vtag);
644 goto out;
645 }
646 rtt_offset = net->cc_mod.rtcc.lbw_rtt >> SCTP_BASE_SYSCTL(sctp_rttvar_rtt);
647 if (nbw < net->cc_mod.rtcc.lbw - bw_offset) {
648 ret = cc_bw_decrease(stcb, net, nbw, rtt_offset, vtag, inst_ind);
649 goto out;
650 }
651 /*
652 * If we reach here then we are in a situation where the bw stayed
653 * the same.
654 */
655 ret = cc_bw_same(stcb, net, nbw, rtt_offset, vtag, inst_ind);
656 out:
657 net->cc_mod.rtcc.last_inst_ind = inst_ind;
658 return (ret);
659 }
660
661 static void
662 sctp_cwnd_update_after_sack_common(struct sctp_tcb *stcb,
663 struct sctp_association *asoc,
664 int accum_moved, int reneged_all SCTP_UNUSED, int will_exit, int use_rtcc)
665 {
666 struct sctp_nets *net;
667 int old_cwnd;
668 uint32_t t_ssthresh, t_cwnd, incr;
669 uint64_t t_ucwnd_sbw;
670 uint64_t t_path_mptcp;
671 uint64_t mptcp_like_alpha;
672 uint32_t srtt;
673 uint64_t max_path;
674
675 /* MT FIXME: Don't compute this over and over again */
676 t_ssthresh = 0;
677 t_cwnd = 0;
678 t_ucwnd_sbw = 0;
679 t_path_mptcp = 0;
680 mptcp_like_alpha = 1;
681 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) ||
682 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2) ||
683 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_MPTCP)) {
684 max_path = 0;
685 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
686 t_ssthresh += net->ssthresh;
687 t_cwnd += net->cwnd;
688 /* lastsa>>3; we don't need to devide ... */
689 srtt = net->lastsa;
690 if (srtt > 0) {
691 uint64_t tmp;
692
693 t_ucwnd_sbw += (uint64_t) net->cwnd / (uint64_t) srtt;
694 t_path_mptcp += (((uint64_t) net->cwnd) << SHIFT_MPTCP_MULTI_Z) /
695 (((uint64_t) net->mtu) * (uint64_t) srtt);
696 tmp = (((uint64_t) net->cwnd) << SHIFT_MPTCP_MULTI_N) /
697 ((uint64_t) net->mtu * (uint64_t) (srtt * srtt));
698 if (tmp > max_path) {
699 max_path = tmp;
700 }
701 }
702 }
703 if (t_path_mptcp > 0) {
704 mptcp_like_alpha = max_path / (t_path_mptcp * t_path_mptcp);
705 } else {
706 mptcp_like_alpha = 1;
707 }
708 }
709 if (t_ssthresh == 0) {
710 t_ssthresh = 1;
711 }
712 if (t_ucwnd_sbw == 0) {
713 t_ucwnd_sbw = 1;
714 }
715 /******************************/
716 /* update cwnd and Early FR */
717 /******************************/
718 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
719
720 #ifdef JANA_CMT_FAST_RECOVERY
721 /*
722 * CMT fast recovery code. Need to debug.
723 */
724 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
725 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) ||
726 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) {
727 net->will_exit_fast_recovery = 1;
728 }
729 }
730 #endif
731 /* if nothing was acked on this destination skip it */
732 if (net->net_ack == 0) {
733 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
734 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
735 }
736 continue;
737 }
738 #ifdef JANA_CMT_FAST_RECOVERY
739 /*
740 * CMT fast recovery code
741 */
742 /*
743 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery
744 * && net->will_exit_fast_recovery == 0) { @@@ Do something
745 * } else if (sctp_cmt_on_off == 0 &&
746 * asoc->fast_retran_loss_recovery && will_exit == 0) {
747 */
748 #endif
749
750 if (asoc->fast_retran_loss_recovery &&
751 (will_exit == 0) &&
752 (asoc->sctp_cmt_on_off == 0)) {
753 /*
754 * If we are in loss recovery we skip any cwnd
755 * update
756 */
757 return;
758 }
759 /*
760 * Did any measurements go on for this network?
761 */
762 if (use_rtcc && (net->cc_mod.rtcc.tls_needs_set > 0)) {
763 uint64_t nbw;
764
765 /*
766 * At this point our bw_bytes has been updated by
767 * incoming sack information.
768 *
769 * But our bw may not yet be set.
770 *
771 */
772 if ((net->cc_mod.rtcc.new_tot_time / 1000) > 0) {
773 nbw = net->cc_mod.rtcc.bw_bytes / (net->cc_mod.rtcc.new_tot_time / 1000);
774 } else {
775 nbw = net->cc_mod.rtcc.bw_bytes;
776 }
777 if (net->cc_mod.rtcc.lbw) {
778 if (cc_bw_limit(stcb, net, nbw)) {
779 /* Hold here, no update */
780 continue;
781 }
782 } else {
783 uint64_t vtag, probepoint;
784
785 probepoint = (((uint64_t) net->cwnd) << 32);
786 probepoint |= ((0xa << 16) | 0);
787 vtag = (net->rtt << 32) |
788 (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) |
789 (stcb->rport);
790
791 SDT_PROBE(sctp, cwnd, net, rttvar,
792 vtag,
793 nbw,
794 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
795 net->flight_size,
796 probepoint);
797 net->cc_mod.rtcc.lbw = nbw;
798 net->cc_mod.rtcc.lbw_rtt = net->rtt;
799 if (net->cc_mod.rtcc.rtt_set_this_sack) {
800 net->cc_mod.rtcc.rtt_set_this_sack = 0;
801 net->cc_mod.rtcc.bw_bytes_at_last_rttc = net->cc_mod.rtcc.bw_bytes;
802 }
803 }
804 }
805 /*
806 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
807 * moved.
808 */
809 if (accum_moved ||
810 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) {
811 /* If the cumulative ack moved we can proceed */
812 if (net->cwnd <= net->ssthresh) {
813 /* We are in slow start */
814 if (net->flight_size + net->net_ack >= net->cwnd) {
815 uint32_t limit;
816
817 old_cwnd = net->cwnd;
818 switch (asoc->sctp_cmt_on_off) {
819 case SCTP_CMT_RPV1:
820 limit = (uint32_t) (((uint64_t) net->mtu *
821 (uint64_t) SCTP_BASE_SYSCTL(sctp_L2_abc_variable) *
822 (uint64_t) net->ssthresh) /
823 (uint64_t) t_ssthresh);
824 incr = (uint32_t) (((uint64_t) net->net_ack *
825 (uint64_t) net->ssthresh) /
826 (uint64_t) t_ssthresh);
827 if (incr > limit) {
828 incr = limit;
829 }
830 if (incr == 0) {
831 incr = 1;
832 }
833 break;
834 case SCTP_CMT_RPV2:
835 /*
836 * lastsa>>3; we don't need
837 * to divide ...
838 */
839 srtt = net->lastsa;
840 if (srtt == 0) {
841 srtt = 1;
842 }
843 limit = (uint32_t) (((uint64_t) net->mtu *
844 (uint64_t) SCTP_BASE_SYSCTL(sctp_L2_abc_variable) *
845 (uint64_t) net->cwnd) /
846 ((uint64_t) srtt * t_ucwnd_sbw));
847 /* INCREASE FACTOR */
848 incr = (uint32_t) (((uint64_t) net->net_ack *
849 (uint64_t) net->cwnd) /
850 ((uint64_t) srtt * t_ucwnd_sbw));
851 /* INCREASE FACTOR */
852 if (incr > limit) {
853 incr = limit;
854 }
855 if (incr == 0) {
856 incr = 1;
857 }
858 break;
859 case SCTP_CMT_MPTCP:
860 limit = (uint32_t) (((uint64_t) net->mtu *
861 mptcp_like_alpha *
862 (uint64_t) SCTP_BASE_SYSCTL(sctp_L2_abc_variable)) >>
863 SHIFT_MPTCP_MULTI);
864 incr = (uint32_t) (((uint64_t) net->net_ack *
865 mptcp_like_alpha) >>
866 SHIFT_MPTCP_MULTI);
867 if (incr > limit) {
868 incr = limit;
869 }
870 if (incr > net->net_ack) {
871 incr = net->net_ack;
872 }
873 if (incr > net->mtu) {
874 incr = net->mtu;
875 }
876 break;
877 default:
878 incr = net->net_ack;
879 if (incr > net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable)) {
880 incr = net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable);
881 }
882 break;
883 }
884 net->cwnd += incr;
885 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
886 sctp_log_cwnd(stcb, net, incr,
887 SCTP_CWND_LOG_FROM_SS);
888 }
889 SDT_PROBE(sctp, cwnd, net, ack,
890 stcb->asoc.my_vtag,
891 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
892 net,
893 old_cwnd, net->cwnd);
894 } else {
895 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
896 sctp_log_cwnd(stcb, net, net->net_ack,
897 SCTP_CWND_LOG_NOADV_SS);
898 }
899 }
900 } else {
901 /* We are in congestion avoidance */
902 /*
903 * Add to pba
904 */
905 net->partial_bytes_acked += net->net_ack;
906
907 if ((net->flight_size + net->net_ack >= net->cwnd) &&
908 (net->partial_bytes_acked >= net->cwnd)) {
909 net->partial_bytes_acked -= net->cwnd;
910 old_cwnd = net->cwnd;
911 switch (asoc->sctp_cmt_on_off) {
912 case SCTP_CMT_RPV1:
913 incr = (uint32_t) (((uint64_t) net->mtu *
914 (uint64_t) net->ssthresh) /
915 (uint64_t) t_ssthresh);
916 if (incr == 0) {
917 incr = 1;
918 }
919 break;
920 case SCTP_CMT_RPV2:
921 /*
922 * lastsa>>3; we don't need
923 * to divide ...
924 */
925 srtt = net->lastsa;
926 if (srtt == 0) {
927 srtt = 1;
928 }
929 incr = (uint32_t) ((uint64_t) net->mtu *
930 (uint64_t) net->cwnd /
931 ((uint64_t) srtt *
932 t_ucwnd_sbw));
933 /* INCREASE FACTOR */
934 if (incr == 0) {
935 incr = 1;
936 }
937 break;
938 case SCTP_CMT_MPTCP:
939 incr = (uint32_t) ((mptcp_like_alpha *
940 (uint64_t) net->cwnd) >>
941 SHIFT_MPTCP_MULTI);
942 if (incr > net->mtu) {
943 incr = net->mtu;
944 }
945 break;
946 default:
947 incr = net->mtu;
948 break;
949 }
950 net->cwnd += incr;
951 SDT_PROBE(sctp, cwnd, net, ack,
952 stcb->asoc.my_vtag,
953 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
954 net,
955 old_cwnd, net->cwnd);
956 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
957 sctp_log_cwnd(stcb, net, net->mtu,
958 SCTP_CWND_LOG_FROM_CA);
959 }
960 } else {
961 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
962 sctp_log_cwnd(stcb, net, net->net_ack,
963 SCTP_CWND_LOG_NOADV_CA);
964 }
965 }
966 }
967 } else {
968 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
969 sctp_log_cwnd(stcb, net, net->mtu,
970 SCTP_CWND_LOG_NO_CUMACK);
971 }
972 }
973 }
974 }
975
976 static void
977 sctp_cwnd_update_exit_pf_common(struct sctp_tcb *stcb, struct sctp_nets *net)
978 {
979 int old_cwnd;
980
981 old_cwnd = net->cwnd;
982 net->cwnd = net->mtu;
983 SDT_PROBE(sctp, cwnd, net, ack,
984 stcb->asoc.my_vtag, ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), net,
985 old_cwnd, net->cwnd);
986 SCTPDBG(SCTP_DEBUG_INDATA1, "Destination %p moved from PF to reachable with cwnd %d.\n",
987 (void *)net, net->cwnd);
988 }
989
990
991 static void
992 sctp_cwnd_update_after_timeout(struct sctp_tcb *stcb, struct sctp_nets *net)
993 {
994 int old_cwnd = net->cwnd;
995 uint32_t t_ssthresh, t_cwnd;
996 uint64_t t_ucwnd_sbw;
997
998 /* MT FIXME: Don't compute this over and over again */
999 t_ssthresh = 0;
1000 t_cwnd = 0;
1001 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) ||
1002 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2)) {
1003 struct sctp_nets *lnet;
1004 uint32_t srtt;
1005
1006 t_ucwnd_sbw = 0;
1007 TAILQ_FOREACH(lnet, &stcb->asoc.nets, sctp_next) {
1008 t_ssthresh += lnet->ssthresh;
1009 t_cwnd += lnet->cwnd;
1010 srtt = lnet->lastsa;
1011 /* lastsa>>3; we don't need to divide ... */
1012 if (srtt > 0) {
1013 t_ucwnd_sbw += (uint64_t) lnet->cwnd / (uint64_t) srtt;
1014 }
1015 }
1016 if (t_ssthresh < 1) {
1017 t_ssthresh = 1;
1018 }
1019 if (t_ucwnd_sbw < 1) {
1020 t_ucwnd_sbw = 1;
1021 }
1022 if (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) {
1023 net->ssthresh = (uint32_t) (((uint64_t) 4 *
1024 (uint64_t) net->mtu *
1025 (uint64_t) net->ssthresh) /
1026 (uint64_t) t_ssthresh);
1027 } else {
1028 uint64_t cc_delta;
1029
1030 srtt = net->lastsa;
1031 /* lastsa>>3; we don't need to divide ... */
1032 if (srtt == 0) {
1033 srtt = 1;
1034 }
1035 cc_delta = t_ucwnd_sbw * (uint64_t) srtt / 2;
1036 if (cc_delta < t_cwnd) {
1037 net->ssthresh = (uint32_t) ((uint64_t) t_cwnd - cc_delta);
1038 } else {
1039 net->ssthresh = net->mtu;
1040 }
1041 }
1042 if ((net->cwnd > t_cwnd / 2) &&
1043 (net->ssthresh < net->cwnd - t_cwnd / 2)) {
1044 net->ssthresh = net->cwnd - t_cwnd / 2;
1045 }
1046 if (net->ssthresh < net->mtu) {
1047 net->ssthresh = net->mtu;
1048 }
1049 } else {
1050 net->ssthresh = max(net->cwnd / 2, 4 * net->mtu);
1051 }
1052 net->cwnd = net->mtu;
1053 net->partial_bytes_acked = 0;
1054 SDT_PROBE(sctp, cwnd, net, to,
1055 stcb->asoc.my_vtag,
1056 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
1057 net,
1058 old_cwnd, net->cwnd);
1059 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1060 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX);
1061 }
1062 }
1063
1064 static void
1065 sctp_cwnd_update_after_ecn_echo_common(struct sctp_tcb *stcb, struct sctp_nets *net,
1066 int in_window, int num_pkt_lost, int use_rtcc)
1067 {
1068 int old_cwnd = net->cwnd;
1069
1070 if ((use_rtcc) && (net->lan_type == SCTP_LAN_LOCAL) && (net->cc_mod.rtcc.use_dccc_ecn)) {
1071 /* Data center Congestion Control */
1072 if (in_window == 0) {
1073 /*
1074 * Go to CA with the cwnd at the point we sent the
1075 * TSN that was marked with a CE.
1076 */
1077 if (net->ecn_prev_cwnd < net->cwnd) {
1078 /* Restore to prev cwnd */
1079 net->cwnd = net->ecn_prev_cwnd - (net->mtu * num_pkt_lost);
1080 } else {
1081 /* Just cut in 1/2 */
1082 net->cwnd /= 2;
1083 }
1084 /* Drop to CA */
1085 net->ssthresh = net->cwnd - (num_pkt_lost * net->mtu);
1086 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1087 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
1088 }
1089 } else {
1090 /*
1091 * Further tuning down required over the drastic
1092 * orginal cut
1093 */
1094 net->ssthresh -= (net->mtu * num_pkt_lost);
1095 net->cwnd -= (net->mtu * num_pkt_lost);
1096 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1097 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
1098 }
1099 }
1100 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
1101 } else {
1102 if (in_window == 0) {
1103 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
1104 net->ssthresh = net->cwnd / 2;
1105 if (net->ssthresh < net->mtu) {
1106 net->ssthresh = net->mtu;
1107 /*
1108 * here back off the timer as well, to slow
1109 * us down
1110 */
1111 net->RTO <<= 1;
1112 }
1113 net->cwnd = net->ssthresh;
1114 SDT_PROBE(sctp, cwnd, net, ecn,
1115 stcb->asoc.my_vtag,
1116 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
1117 net,
1118 old_cwnd, net->cwnd);
1119 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1120 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
1121 }
1122 }
1123 }
1124
1125 }
1126
1127 static void
1128 sctp_cwnd_update_after_packet_dropped(struct sctp_tcb *stcb,
1129 struct sctp_nets *net, struct sctp_pktdrop_chunk *cp,
1130 uint32_t * bottle_bw, uint32_t * on_queue)
1131 {
1132 uint32_t bw_avail;
1133 int rtt;
1134 unsigned int incr;
1135 int old_cwnd = net->cwnd;
1136
1137 /* need real RTT in msd for this calc */
1138 rtt = net->rtt / 1000;
1139 /* get bottle neck bw */
1140 *bottle_bw = ntohl(cp->bottle_bw);
1141 /* and whats on queue */
1142 *on_queue = ntohl(cp->current_onq);
1143 /*
1144 * adjust the on-queue if our flight is more it could be that the
1145 * router has not yet gotten data "in-flight" to it
1146 */
1147 if (*on_queue < net->flight_size)
1148 *on_queue = net->flight_size;
1149 /* calculate the available space */
1150 bw_avail = (*bottle_bw * rtt) / 1000;
1151 if (bw_avail > *bottle_bw) {
1152 /*
1153 * Cap the growth to no more than the bottle neck. This can
1154 * happen as RTT slides up due to queues. It also means if
1155 * you have more than a 1 second RTT with a empty queue you
1156 * will be limited to the bottle_bw per second no matter if
1157 * other points have 1/2 the RTT and you could get more
1158 * out...
1159 */
1160 bw_avail = *bottle_bw;
1161 }
1162 if (*on_queue > bw_avail) {
1163 /*
1164 * No room for anything else don't allow anything else to be
1165 * "added to the fire".
1166 */
1167 int seg_inflight, seg_onqueue, my_portion;
1168
1169 net->partial_bytes_acked = 0;
1170
1171 /* how much are we over queue size? */
1172 incr = *on_queue - bw_avail;
1173 if (stcb->asoc.seen_a_sack_this_pkt) {
1174 /*
1175 * undo any cwnd adjustment that the sack might have
1176 * made
1177 */
1178 net->cwnd = net->prev_cwnd;
1179 }
1180 /* Now how much of that is mine? */
1181 seg_inflight = net->flight_size / net->mtu;
1182 seg_onqueue = *on_queue / net->mtu;
1183 my_portion = (incr * seg_inflight) / seg_onqueue;
1184
1185 /* Have I made an adjustment already */
1186 if (net->cwnd > net->flight_size) {
1187 /*
1188 * for this flight I made an adjustment we need to
1189 * decrease the portion by a share our previous
1190 * adjustment.
1191 */
1192 int diff_adj;
1193
1194 diff_adj = net->cwnd - net->flight_size;
1195 if (diff_adj > my_portion)
1196 my_portion = 0;
1197 else
1198 my_portion -= diff_adj;
1199 }
1200 /*
1201 * back down to the previous cwnd (assume we have had a sack
1202 * before this packet). minus what ever portion of the
1203 * overage is my fault.
1204 */
1205 net->cwnd -= my_portion;
1206
1207 /* we will NOT back down more than 1 MTU */
1208 if (net->cwnd <= net->mtu) {
1209 net->cwnd = net->mtu;
1210 }
1211 /* force into CA */
1212 net->ssthresh = net->cwnd - 1;
1213 } else {
1214 /*
1215 * Take 1/4 of the space left or max burst up .. whichever
1216 * is less.
1217 */
1218 incr = (bw_avail - *on_queue) >> 2;
1219 if ((stcb->asoc.max_burst > 0) &&
1220 (stcb->asoc.max_burst * net->mtu < incr)) {
1221 incr = stcb->asoc.max_burst * net->mtu;
1222 }
1223 net->cwnd += incr;
1224 }
1225 if (net->cwnd > bw_avail) {
1226 /* We can't exceed the pipe size */
1227 net->cwnd = bw_avail;
1228 }
1229 if (net->cwnd < net->mtu) {
1230 /* We always have 1 MTU */
1231 net->cwnd = net->mtu;
1232 }
1233 if (net->cwnd - old_cwnd != 0) {
1234 /* log only changes */
1235 SDT_PROBE(sctp, cwnd, net, pd,
1236 stcb->asoc.my_vtag,
1237 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
1238 net,
1239 old_cwnd, net->cwnd);
1240 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1241 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
1242 SCTP_CWND_LOG_FROM_SAT);
1243 }
1244 }
1245 }
1246
1247 static void
1248 sctp_cwnd_update_after_output(struct sctp_tcb *stcb,
1249 struct sctp_nets *net, int burst_limit)
1250 {
1251 int old_cwnd = net->cwnd;
1252
1253 if (net->ssthresh < net->cwnd)
1254 net->ssthresh = net->cwnd;
1255 if (burst_limit) {
1256 net->cwnd = (net->flight_size + (burst_limit * net->mtu));
1257 SDT_PROBE(sctp, cwnd, net, bl,
1258 stcb->asoc.my_vtag,
1259 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
1260 net,
1261 old_cwnd, net->cwnd);
1262 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1263 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_BRST);
1264 }
1265 }
1266 }
1267
1268 static void
1269 sctp_cwnd_update_after_sack(struct sctp_tcb *stcb,
1270 struct sctp_association *asoc,
1271 int accum_moved, int reneged_all, int will_exit)
1272 {
1273 /* Passing a zero argument in last disables the rtcc algoritm */
1274 sctp_cwnd_update_after_sack_common(stcb, asoc, accum_moved, reneged_all, will_exit, 0);
1275 }
1276
1277 static void
1278 sctp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net,
1279 int in_window, int num_pkt_lost)
1280 {
1281 /* Passing a zero argument in last disables the rtcc algoritm */
1282 sctp_cwnd_update_after_ecn_echo_common(stcb, net, in_window, num_pkt_lost, 0);
1283 }
1284
1285 /* Here starts the RTCCVAR type CC invented by RRS which
1286 * is a slight mod to RFC2581. We reuse a common routine or
1287 * two since these algoritms are so close and need to
1288 * remain the same.
1289 */
1290 static void
1291 sctp_cwnd_update_rtcc_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net,
1292 int in_window, int num_pkt_lost)
1293 {
1294 sctp_cwnd_update_after_ecn_echo_common(stcb, net, in_window, num_pkt_lost, 1);
1295 }
1296
1297
1298 static
1299 void
1300 sctp_cwnd_update_rtcc_tsn_acknowledged(struct sctp_nets *net,
1301 struct sctp_tmit_chunk *tp1)
1302 {
1303 net->cc_mod.rtcc.bw_bytes += tp1->send_size;
1304 }
1305
1306 static void
1307 sctp_cwnd_prepare_rtcc_net_for_sack(struct sctp_tcb *stcb SCTP_UNUSED,
1308 struct sctp_nets *net)
1309 {
1310 if (net->cc_mod.rtcc.tls_needs_set > 0) {
1311 /* We had a bw measurment going on */
1312 struct timeval ltls;
1313
1314 SCTP_GETPTIME_TIMEVAL(<ls);
1315 timevalsub(<ls, &net->cc_mod.rtcc.tls);
1316 net->cc_mod.rtcc.new_tot_time = (ltls.tv_sec * 1000000) + ltls.tv_usec;
1317 }
1318 }
1319
1320 static void
1321 sctp_cwnd_new_rtcc_transmission_begins(struct sctp_tcb *stcb,
1322 struct sctp_nets *net)
1323 {
1324 uint64_t vtag, probepoint;
1325
1326 if (net->cc_mod.rtcc.lbw) {
1327 /* Clear the old bw.. we went to 0 in-flight */
1328 vtag = (net->rtt << 32) | (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) |
1329 (stcb->rport);
1330 probepoint = (((uint64_t) net->cwnd) << 32);
1331 /* Probe point 8 */
1332 probepoint |= ((8 << 16) | 0);
1333 SDT_PROBE(sctp, cwnd, net, rttvar,
1334 vtag,
1335 ((net->cc_mod.rtcc.lbw << 32) | 0),
1336 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt),
1337 net->flight_size,
1338 probepoint);
1339 net->cc_mod.rtcc.lbw_rtt = 0;
1340 net->cc_mod.rtcc.cwnd_at_bw_set = 0;
1341 net->cc_mod.rtcc.lbw = 0;
1342 net->cc_mod.rtcc.bw_bytes_at_last_rttc = 0;
1343 net->cc_mod.rtcc.vol_reduce = 0;
1344 net->cc_mod.rtcc.bw_tot_time = 0;
1345 net->cc_mod.rtcc.bw_bytes = 0;
1346 net->cc_mod.rtcc.tls_needs_set = 0;
1347 if (net->cc_mod.rtcc.steady_step) {
1348 net->cc_mod.rtcc.vol_reduce = 0;
1349 net->cc_mod.rtcc.step_cnt = 0;
1350 net->cc_mod.rtcc.last_step_state = 0;
1351 }
1352 if (net->cc_mod.rtcc.ret_from_eq) {
1353 /* less aggressive one - reset cwnd too */
1354 uint32_t cwnd_in_mtu, cwnd;
1355
1356 cwnd_in_mtu = SCTP_BASE_SYSCTL(sctp_initial_cwnd);
1357 if (cwnd_in_mtu == 0) {
1358 /*
1359 * Using 0 means that the value of RFC 4960
1360 * is used.
1361 */
1362 cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
1363 } else {
1364 /*
1365 * We take the minimum of the burst limit
1366 * and the initial congestion window.
1367 */
1368 if ((stcb->asoc.max_burst > 0) && (cwnd_in_mtu > stcb->asoc.max_burst))
1369 cwnd_in_mtu = stcb->asoc.max_burst;
1370 cwnd = (net->mtu - sizeof(struct sctphdr)) * cwnd_in_mtu;
1371 }
1372 if (net->cwnd > cwnd) {
1373 /*
1374 * Only set if we are not a timeout (i.e.
1375 * down to 1 mtu)
1376 */
1377 net->cwnd = cwnd;
1378 }
1379 }
1380 }
1381 }
1382
1383 static void
1384 sctp_set_rtcc_initial_cc_param(struct sctp_tcb *stcb,
1385 struct sctp_nets *net)
1386 {
1387 uint64_t vtag, probepoint;
1388
1389 sctp_set_initial_cc_param(stcb, net);
1390 stcb->asoc.use_precise_time = 1;
1391 probepoint = (((uint64_t) net->cwnd) << 32);
1392 probepoint |= ((9 << 16) | 0);
1393 vtag = (net->rtt << 32) |
1394 (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) |
1395 (stcb->rport);
1396 SDT_PROBE(sctp, cwnd, net, rttvar,
1397 vtag,
1398 0,
1399 0,
1400 0,
1401 probepoint);
1402 net->cc_mod.rtcc.lbw_rtt = 0;
1403 net->cc_mod.rtcc.cwnd_at_bw_set = 0;
1404 net->cc_mod.rtcc.vol_reduce = 0;
1405 net->cc_mod.rtcc.lbw = 0;
1406 net->cc_mod.rtcc.vol_reduce = 0;
1407 net->cc_mod.rtcc.bw_bytes_at_last_rttc = 0;
1408 net->cc_mod.rtcc.bw_tot_time = 0;
1409 net->cc_mod.rtcc.bw_bytes = 0;
1410 net->cc_mod.rtcc.tls_needs_set = 0;
1411 net->cc_mod.rtcc.ret_from_eq = SCTP_BASE_SYSCTL(sctp_rttvar_eqret);
1412 net->cc_mod.rtcc.steady_step = SCTP_BASE_SYSCTL(sctp_steady_step);
1413 net->cc_mod.rtcc.use_dccc_ecn = SCTP_BASE_SYSCTL(sctp_use_dccc_ecn);
1414 net->cc_mod.rtcc.step_cnt = 0;
1415 net->cc_mod.rtcc.last_step_state = 0;
1416
1417
1418 }
1419
1420 static int
1421 sctp_cwnd_rtcc_socket_option(struct sctp_tcb *stcb, int setorget,
1422 struct sctp_cc_option *cc_opt)
1423 {
1424 struct sctp_nets *net;
1425
1426 if (setorget == 1) {
1427 /* a set */
1428 if (cc_opt->option == SCTP_CC_OPT_RTCC_SETMODE) {
1429 if ((cc_opt->aid_value.assoc_value != 0) &&
1430 (cc_opt->aid_value.assoc_value != 1)) {
1431 return (EINVAL);
1432 }
1433 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
1434 net->cc_mod.rtcc.ret_from_eq = cc_opt->aid_value.assoc_value;
1435 }
1436 } else if (cc_opt->option == SCTP_CC_OPT_USE_DCCC_ECN) {
1437 if ((cc_opt->aid_value.assoc_value != 0) &&
1438 (cc_opt->aid_value.assoc_value != 1)) {
1439 return (EINVAL);
1440 }
1441 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
1442 net->cc_mod.rtcc.use_dccc_ecn = cc_opt->aid_value.assoc_value;
1443 }
1444 } else if (cc_opt->option == SCTP_CC_OPT_STEADY_STEP) {
1445 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) {
1446 net->cc_mod.rtcc.steady_step = cc_opt->aid_value.assoc_value;
1447 }
1448 } else {
1449 return (EINVAL);
1450 }
1451 } else {
1452 /* a get */
1453 if (cc_opt->option == SCTP_CC_OPT_RTCC_SETMODE) {
1454 net = TAILQ_FIRST(&stcb->asoc.nets);
1455 if (net == NULL) {
1456 return (EFAULT);
1457 }
1458 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.ret_from_eq;
1459 } else if (cc_opt->option == SCTP_CC_OPT_USE_DCCC_ECN) {
1460 net = TAILQ_FIRST(&stcb->asoc.nets);
1461 if (net == NULL) {
1462 return (EFAULT);
1463 }
1464 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.use_dccc_ecn;
1465 } else if (cc_opt->option == SCTP_CC_OPT_STEADY_STEP) {
1466 net = TAILQ_FIRST(&stcb->asoc.nets);
1467 if (net == NULL) {
1468 return (EFAULT);
1469 }
1470 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.steady_step;
1471 } else {
1472 return (EINVAL);
1473 }
1474 }
1475 return (0);
1476 }
1477
1478 static void
1479 sctp_cwnd_update_rtcc_packet_transmitted(struct sctp_tcb *stcb SCTP_UNUSED,
1480 struct sctp_nets *net)
1481 {
1482 if (net->cc_mod.rtcc.tls_needs_set == 0) {
1483 SCTP_GETPTIME_TIMEVAL(&net->cc_mod.rtcc.tls);
1484 net->cc_mod.rtcc.tls_needs_set = 2;
1485 }
1486 }
1487
1488 static void
1489 sctp_cwnd_update_rtcc_after_sack(struct sctp_tcb *stcb,
1490 struct sctp_association *asoc,
1491 int accum_moved, int reneged_all, int will_exit)
1492 {
1493 /* Passing a one argument at the last enables the rtcc algoritm */
1494 sctp_cwnd_update_after_sack_common(stcb, asoc, accum_moved, reneged_all, will_exit, 1);
1495 }
1496
1497 static void
1498 sctp_rtt_rtcc_calculated(struct sctp_tcb *stcb SCTP_UNUSED,
1499 struct sctp_nets *net,
1500 struct timeval *now SCTP_UNUSED)
1501 {
1502 net->cc_mod.rtcc.rtt_set_this_sack = 1;
1503 }
1504
1505 /* Here starts Sally Floyds HS-TCP */
1506
1507 struct sctp_hs_raise_drop {
1508 int32_t cwnd;
1509 int32_t increase;
1510 int32_t drop_percent;
1511 };
1512
1513 #define SCTP_HS_TABLE_SIZE 73
1514
1515 struct sctp_hs_raise_drop sctp_cwnd_adjust[SCTP_HS_TABLE_SIZE] = {
1516 {38, 1, 50}, /* 0 */
1517 {118, 2, 44}, /* 1 */
1518 {221, 3, 41}, /* 2 */
1519 {347, 4, 38}, /* 3 */
1520 {495, 5, 37}, /* 4 */
1521 {663, 6, 35}, /* 5 */
1522 {851, 7, 34}, /* 6 */
1523 {1058, 8, 33}, /* 7 */
1524 {1284, 9, 32}, /* 8 */
1525 {1529, 10, 31}, /* 9 */
1526 {1793, 11, 30}, /* 10 */
1527 {2076, 12, 29}, /* 11 */
1528 {2378, 13, 28}, /* 12 */
1529 {2699, 14, 28}, /* 13 */
1530 {3039, 15, 27}, /* 14 */
1531 {3399, 16, 27}, /* 15 */
1532 {3778, 17, 26}, /* 16 */
1533 {4177, 18, 26}, /* 17 */
1534 {4596, 19, 25}, /* 18 */
1535 {5036, 20, 25}, /* 19 */
1536 {5497, 21, 24}, /* 20 */
1537 {5979, 22, 24}, /* 21 */
1538 {6483, 23, 23}, /* 22 */
1539 {7009, 24, 23}, /* 23 */
1540 {7558, 25, 22}, /* 24 */
1541 {8130, 26, 22}, /* 25 */
1542 {8726, 27, 22}, /* 26 */
1543 {9346, 28, 21}, /* 27 */
1544 {9991, 29, 21}, /* 28 */
1545 {10661, 30, 21}, /* 29 */
1546 {11358, 31, 20}, /* 30 */
1547 {12082, 32, 20}, /* 31 */
1548 {12834, 33, 20}, /* 32 */
1549 {13614, 34, 19}, /* 33 */
1550 {14424, 35, 19}, /* 34 */
1551 {15265, 36, 19}, /* 35 */
1552 {16137, 37, 19}, /* 36 */
1553 {17042, 38, 18}, /* 37 */
1554 {17981, 39, 18}, /* 38 */
1555 {18955, 40, 18}, /* 39 */
1556 {19965, 41, 17}, /* 40 */
1557 {21013, 42, 17}, /* 41 */
1558 {22101, 43, 17}, /* 42 */
1559 {23230, 44, 17}, /* 43 */
1560 {24402, 45, 16}, /* 44 */
1561 {25618, 46, 16}, /* 45 */
1562 {26881, 47, 16}, /* 46 */
1563 {28193, 48, 16}, /* 47 */
1564 {29557, 49, 15}, /* 48 */
1565 {30975, 50, 15}, /* 49 */
1566 {32450, 51, 15}, /* 50 */
1567 {33986, 52, 15}, /* 51 */
1568 {35586, 53, 14}, /* 52 */
1569 {37253, 54, 14}, /* 53 */
1570 {38992, 55, 14}, /* 54 */
1571 {40808, 56, 14}, /* 55 */
1572 {42707, 57, 13}, /* 56 */
1573 {44694, 58, 13}, /* 57 */
1574 {46776, 59, 13}, /* 58 */
1575 {48961, 60, 13}, /* 59 */
1576 {51258, 61, 13}, /* 60 */
1577 {53677, 62, 12}, /* 61 */
1578 {56230, 63, 12}, /* 62 */
1579 {58932, 64, 12}, /* 63 */
1580 {61799, 65, 12}, /* 64 */
1581 {64851, 66, 11}, /* 65 */
1582 {68113, 67, 11}, /* 66 */
1583 {71617, 68, 11}, /* 67 */
1584 {75401, 69, 10}, /* 68 */
1585 {79517, 70, 10}, /* 69 */
1586 {84035, 71, 10}, /* 70 */
1587 {89053, 72, 10}, /* 71 */
1588 {94717, 73, 9} /* 72 */
1589 };
1590
1591 static void
1592 sctp_hs_cwnd_increase(struct sctp_tcb *stcb, struct sctp_nets *net)
1593 {
1594 int cur_val, i, indx, incr;
1595
1596 cur_val = net->cwnd >> 10;
1597 indx = SCTP_HS_TABLE_SIZE - 1;
1598
1599 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
1600 /* normal mode */
1601 if (net->net_ack > net->mtu) {
1602 net->cwnd += net->mtu;
1603 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1604 sctp_log_cwnd(stcb, net, net->mtu, SCTP_CWND_LOG_FROM_SS);
1605 }
1606 } else {
1607 net->cwnd += net->net_ack;
1608 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1609 sctp_log_cwnd(stcb, net, net->net_ack, SCTP_CWND_LOG_FROM_SS);
1610 }
1611 }
1612 } else {
1613 for (i = net->last_hs_used; i < SCTP_HS_TABLE_SIZE; i++) {
1614 if (cur_val < sctp_cwnd_adjust[i].cwnd) {
1615 indx = i;
1616 break;
1617 }
1618 }
1619 net->last_hs_used = indx;
1620 incr = ((sctp_cwnd_adjust[indx].increase) << 10);
1621 net->cwnd += incr;
1622 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1623 sctp_log_cwnd(stcb, net, incr, SCTP_CWND_LOG_FROM_SS);
1624 }
1625 }
1626 }
1627
1628 static void
1629 sctp_hs_cwnd_decrease(struct sctp_tcb *stcb, struct sctp_nets *net)
1630 {
1631 int cur_val, i, indx;
1632 int old_cwnd = net->cwnd;
1633
1634 cur_val = net->cwnd >> 10;
1635 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
1636 /* normal mode */
1637 net->ssthresh = net->cwnd / 2;
1638 if (net->ssthresh < (net->mtu * 2)) {
1639 net->ssthresh = 2 * net->mtu;
1640 }
1641 net->cwnd = net->ssthresh;
1642 } else {
1643 /* drop by the proper amount */
1644 net->ssthresh = net->cwnd - (int)((net->cwnd / 100) *
1645 sctp_cwnd_adjust[net->last_hs_used].drop_percent);
1646 net->cwnd = net->ssthresh;
1647 /* now where are we */
1648 indx = net->last_hs_used;
1649 cur_val = net->cwnd >> 10;
1650 /* reset where we are in the table */
1651 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
1652 /* feel out of hs */
1653 net->last_hs_used = 0;
1654 } else {
1655 for (i = indx; i >= 1; i--) {
1656 if (cur_val > sctp_cwnd_adjust[i - 1].cwnd) {
1657 break;
1658 }
1659 }
1660 net->last_hs_used = indx;
1661 }
1662 }
1663 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1664 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_FR);
1665 }
1666 }
1667
1668 static void
1669 sctp_hs_cwnd_update_after_fr(struct sctp_tcb *stcb,
1670 struct sctp_association *asoc)
1671 {
1672 struct sctp_nets *net;
1673
1674 /*
1675 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) &&
1676 * (net->fast_retran_loss_recovery == 0)))
1677 */
1678 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
1679 if ((asoc->fast_retran_loss_recovery == 0) ||
1680 (asoc->sctp_cmt_on_off > 0)) {
1681 /* out of a RFC2582 Fast recovery window? */
1682 if (net->net_ack > 0) {
1683 /*
1684 * per section 7.2.3, are there any
1685 * destinations that had a fast retransmit
1686 * to them. If so what we need to do is
1687 * adjust ssthresh and cwnd.
1688 */
1689 struct sctp_tmit_chunk *lchk;
1690
1691 sctp_hs_cwnd_decrease(stcb, net);
1692
1693 lchk = TAILQ_FIRST(&asoc->send_queue);
1694
1695 net->partial_bytes_acked = 0;
1696 /* Turn on fast recovery window */
1697 asoc->fast_retran_loss_recovery = 1;
1698 if (lchk == NULL) {
1699 /* Mark end of the window */
1700 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
1701 } else {
1702 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
1703 }
1704
1705 /*
1706 * CMT fast recovery -- per destination
1707 * recovery variable.
1708 */
1709 net->fast_retran_loss_recovery = 1;
1710
1711 if (lchk == NULL) {
1712 /* Mark end of the window */
1713 net->fast_recovery_tsn = asoc->sending_seq - 1;
1714 } else {
1715 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
1716 }
1717
1718 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
1719 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
1720 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
1721 stcb->sctp_ep, stcb, net);
1722 }
1723 } else if (net->net_ack > 0) {
1724 /*
1725 * Mark a peg that we WOULD have done a cwnd
1726 * reduction but RFC2582 prevented this action.
1727 */
1728 SCTP_STAT_INCR(sctps_fastretransinrtt);
1729 }
1730 }
1731 }
1732
1733 static void
1734 sctp_hs_cwnd_update_after_sack(struct sctp_tcb *stcb,
1735 struct sctp_association *asoc,
1736 int accum_moved, int reneged_all SCTP_UNUSED, int will_exit)
1737 {
1738 struct sctp_nets *net;
1739
1740 /******************************/
1741 /* update cwnd and Early FR */
1742 /******************************/
1743 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
1744
1745 #ifdef JANA_CMT_FAST_RECOVERY
1746 /*
1747 * CMT fast recovery code. Need to debug.
1748 */
1749 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
1750 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) ||
1751 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) {
1752 net->will_exit_fast_recovery = 1;
1753 }
1754 }
1755 #endif
1756 /* if nothing was acked on this destination skip it */
1757 if (net->net_ack == 0) {
1758 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1759 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
1760 }
1761 continue;
1762 }
1763 #ifdef JANA_CMT_FAST_RECOVERY
1764 /*
1765 * CMT fast recovery code
1766 */
1767 /*
1768 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery
1769 * && net->will_exit_fast_recovery == 0) { @@@ Do something
1770 * } else if (sctp_cmt_on_off == 0 &&
1771 * asoc->fast_retran_loss_recovery && will_exit == 0) {
1772 */
1773 #endif
1774
1775 if (asoc->fast_retran_loss_recovery &&
1776 (will_exit == 0) &&
1777 (asoc->sctp_cmt_on_off == 0)) {
1778 /*
1779 * If we are in loss recovery we skip any cwnd
1780 * update
1781 */
1782 return;
1783 }
1784 /*
1785 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
1786 * moved.
1787 */
1788 if (accum_moved ||
1789 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) {
1790 /* If the cumulative ack moved we can proceed */
1791 if (net->cwnd <= net->ssthresh) {
1792 /* We are in slow start */
1793 if (net->flight_size + net->net_ack >= net->cwnd) {
1794
1795 sctp_hs_cwnd_increase(stcb, net);
1796
1797 } else {
1798 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1799 sctp_log_cwnd(stcb, net, net->net_ack,
1800 SCTP_CWND_LOG_NOADV_SS);
1801 }
1802 }
1803 } else {
1804 /* We are in congestion avoidance */
1805 net->partial_bytes_acked += net->net_ack;
1806 if ((net->flight_size + net->net_ack >= net->cwnd) &&
1807 (net->partial_bytes_acked >= net->cwnd)) {
1808 net->partial_bytes_acked -= net->cwnd;
1809 net->cwnd += net->mtu;
1810 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1811 sctp_log_cwnd(stcb, net, net->mtu,
1812 SCTP_CWND_LOG_FROM_CA);
1813 }
1814 } else {
1815 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1816 sctp_log_cwnd(stcb, net, net->net_ack,
1817 SCTP_CWND_LOG_NOADV_CA);
1818 }
1819 }
1820 }
1821 } else {
1822 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1823 sctp_log_cwnd(stcb, net, net->mtu,
1824 SCTP_CWND_LOG_NO_CUMACK);
1825 }
1826 }
1827 }
1828 }
1829
1830
1831 /*
1832 * H-TCP congestion control. The algorithm is detailed in:
1833 * R.N.Shorten, D.J.Leith:
1834 * "H-TCP: TCP for high-speed and long-distance networks"
1835 * Proc. PFLDnet, Argonne, 2004.
1836 * http://www.hamilton.ie/net/htcp3.pdf
1837 */
1838
1839
1840 static int use_rtt_scaling = 1;
1841 static int use_bandwidth_switch = 1;
1842
1843 static inline int
1844 between(uint32_t seq1, uint32_t seq2, uint32_t seq3)
1845 {
1846 return (seq3 - seq2 >= seq1 - seq2);
1847 }
1848
1849 static inline uint32_t
1850 htcp_cong_time(struct htcp *ca)
1851 {
1852 return (sctp_get_tick_count() - ca->last_cong);
1853 }
1854
1855 static inline uint32_t
1856 htcp_ccount(struct htcp *ca)
1857 {
1858 return (htcp_cong_time(ca) / ca->minRTT);
1859 }
1860
1861 static inline void
1862 htcp_reset(struct htcp *ca)
1863 {
1864 ca->undo_last_cong = ca->last_cong;
1865 ca->undo_maxRTT = ca->maxRTT;
1866 ca->undo_old_maxB = ca->old_maxB;
1867 ca->last_cong = sctp_get_tick_count();
1868 }
1869
1870 #ifdef SCTP_NOT_USED
1871
1872 static uint32_t
1873 htcp_cwnd_undo(struct sctp_tcb *stcb, struct sctp_nets *net)
1874 {
1875 net->cc_mod.htcp_ca.last_cong = net->cc_mod.htcp_ca.undo_last_cong;
1876 net->cc_mod.htcp_ca.maxRTT = net->cc_mod.htcp_ca.undo_maxRTT;
1877 net->cc_mod.htcp_ca.old_maxB = net->cc_mod.htcp_ca.undo_old_maxB;
1878 return (max(net->cwnd, ((net->ssthresh / net->mtu << 7) / net->cc_mod.htcp_ca.beta) * net->mtu));
1879 }
1880
1881 #endif
1882
1883 static inline void
1884 measure_rtt(struct sctp_nets *net)
1885 {
1886 uint32_t srtt = net->lastsa >> SCTP_RTT_SHIFT;
1887
1888 /* keep track of minimum RTT seen so far, minRTT is zero at first */
1889 if (net->cc_mod.htcp_ca.minRTT > srtt || !net->cc_mod.htcp_ca.minRTT)
1890 net->cc_mod.htcp_ca.minRTT = srtt;
1891
1892 /* max RTT */
1893 if (net->fast_retran_ip == 0 && net->ssthresh < 0xFFFF && htcp_ccount(&net->cc_mod.htcp_ca) > 3) {
1894 if (net->cc_mod.htcp_ca.maxRTT < net->cc_mod.htcp_ca.minRTT)
1895 net->cc_mod.htcp_ca.maxRTT = net->cc_mod.htcp_ca.minRTT;
1896 if (net->cc_mod.htcp_ca.maxRTT < srtt && srtt <= net->cc_mod.htcp_ca.maxRTT + MSEC_TO_TICKS(20))
1897 net->cc_mod.htcp_ca.maxRTT = srtt;
1898 }
1899 }
1900
1901 static void
1902 measure_achieved_throughput(struct sctp_nets *net)
1903 {
1904 uint32_t now = sctp_get_tick_count();
1905
1906 if (net->fast_retran_ip == 0)
1907 net->cc_mod.htcp_ca.bytes_acked = net->net_ack;
1908
1909 if (!use_bandwidth_switch)
1910 return;
1911
1912 /* achieved throughput calculations */
1913 /* JRS - not 100% sure of this statement */
1914 if (net->fast_retran_ip == 1) {
1915 net->cc_mod.htcp_ca.bytecount = 0;
1916 net->cc_mod.htcp_ca.lasttime = now;
1917 return;
1918 }
1919 net->cc_mod.htcp_ca.bytecount += net->net_ack;
1920 if ((net->cc_mod.htcp_ca.bytecount >= net->cwnd - (((net->cc_mod.htcp_ca.alpha >> 7) ? (net->cc_mod.htcp_ca.alpha >> 7) : 1) * net->mtu)) &&
1921 (now - net->cc_mod.htcp_ca.lasttime >= net->cc_mod.htcp_ca.minRTT) &&
1922 (net->cc_mod.htcp_ca.minRTT > 0)) {
1923 uint32_t cur_Bi = net->cc_mod.htcp_ca.bytecount / net->mtu * hz / (now - net->cc_mod.htcp_ca.lasttime);
1924
1925 if (htcp_ccount(&net->cc_mod.htcp_ca) <= 3) {
1926 /* just after backoff */
1927 net->cc_mod.htcp_ca.minB = net->cc_mod.htcp_ca.maxB = net->cc_mod.htcp_ca.Bi = cur_Bi;
1928 } else {
1929 net->cc_mod.htcp_ca.Bi = (3 * net->cc_mod.htcp_ca.Bi + cur_Bi) / 4;
1930 if (net->cc_mod.htcp_ca.Bi > net->cc_mod.htcp_ca.maxB)
1931 net->cc_mod.htcp_ca.maxB = net->cc_mod.htcp_ca.Bi;
1932 if (net->cc_mod.htcp_ca.minB > net->cc_mod.htcp_ca.maxB)
1933 net->cc_mod.htcp_ca.minB = net->cc_mod.htcp_ca.maxB;
1934 }
1935 net->cc_mod.htcp_ca.bytecount = 0;
1936 net->cc_mod.htcp_ca.lasttime = now;
1937 }
1938 }
1939
1940 static inline void
1941 htcp_beta_update(struct htcp *ca, uint32_t minRTT, uint32_t maxRTT)
1942 {
1943 if (use_bandwidth_switch) {
1944 uint32_t maxB = ca->maxB;
1945 uint32_t old_maxB = ca->old_maxB;
1946
1947 ca->old_maxB = ca->maxB;
1948
1949 if (!between(5 * maxB, 4 * old_maxB, 6 * old_maxB)) {
1950 ca->beta = BETA_MIN;
1951 ca->modeswitch = 0;
1952 return;
1953 }
1954 }
1955 if (ca->modeswitch && minRTT > (uint32_t) MSEC_TO_TICKS(10) && maxRTT) {
1956 ca->beta = (minRTT << 7) / maxRTT;
1957 if (ca->beta < BETA_MIN)
1958 ca->beta = BETA_MIN;
1959 else if (ca->beta > BETA_MAX)
1960 ca->beta = BETA_MAX;
1961 } else {
1962 ca->beta = BETA_MIN;
1963 ca->modeswitch = 1;
1964 }
1965 }
1966
1967 static inline void
1968 htcp_alpha_update(struct htcp *ca)
1969 {
1970 uint32_t minRTT = ca->minRTT;
1971 uint32_t factor = 1;
1972 uint32_t diff = htcp_cong_time(ca);
1973
1974 if (diff > (uint32_t) hz) {
1975 diff -= hz;
1976 factor = 1 + (10 * diff + ((diff / 2) * (diff / 2) / hz)) / hz;
1977 }
1978 if (use_rtt_scaling && minRTT) {
1979 uint32_t scale = (hz << 3) / (10 * minRTT);
1980
1981 scale = min(max(scale, 1U << 2), 10U << 3); /* clamping ratio to
1982 * interval [0.5,10]<<3 */
1983 factor = (factor << 3) / scale;
1984 if (!factor)
1985 factor = 1;
1986 }
1987 ca->alpha = 2 * factor * ((1 << 7) - ca->beta);
1988 if (!ca->alpha)
1989 ca->alpha = ALPHA_BASE;
1990 }
1991
1992 /* After we have the rtt data to calculate beta, we'd still prefer to wait one
1993 * rtt before we adjust our beta to ensure we are working from a consistent
1994 * data.
1995 *
1996 * This function should be called when we hit a congestion event since only at
1997 * that point do we really have a real sense of maxRTT (the queues en route
1998 * were getting just too full now).
1999 */
2000 static void
2001 htcp_param_update(struct sctp_nets *net)
2002 {
2003 uint32_t minRTT = net->cc_mod.htcp_ca.minRTT;
2004 uint32_t maxRTT = net->cc_mod.htcp_ca.maxRTT;
2005
2006 htcp_beta_update(&net->cc_mod.htcp_ca, minRTT, maxRTT);
2007 htcp_alpha_update(&net->cc_mod.htcp_ca);
2008
2009 /*
2010 * add slowly fading memory for maxRTT to accommodate routing
2011 * changes etc
2012 */
2013 if (minRTT > 0 && maxRTT > minRTT)
2014 net->cc_mod.htcp_ca.maxRTT = minRTT + ((maxRTT - minRTT) * 95) / 100;
2015 }
2016
2017 static uint32_t
2018 htcp_recalc_ssthresh(struct sctp_nets *net)
2019 {
2020 htcp_param_update(net);
2021 return (max(((net->cwnd / net->mtu * net->cc_mod.htcp_ca.beta) >> 7) * net->mtu, 2U * net->mtu));
2022 }
2023
2024 static void
2025 htcp_cong_avoid(struct sctp_tcb *stcb, struct sctp_nets *net)
2026 {
2027 /*-
2028 * How to handle these functions?
2029 * if (!tcp_is_cwnd_limited(sk, in_flight)) RRS - good question.
2030 * return;
2031 */
2032 if (net->cwnd <= net->ssthresh) {
2033 /* We are in slow start */
2034 if (net->flight_size + net->net_ack >= net->cwnd) {
2035 if (net->net_ack > (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable))) {
2036 net->cwnd += (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable));
2037 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2038 sctp_log_cwnd(stcb, net, net->mtu,
2039 SCTP_CWND_LOG_FROM_SS);
2040 }
2041 } else {
2042 net->cwnd += net->net_ack;
2043 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2044 sctp_log_cwnd(stcb, net, net->net_ack,
2045 SCTP_CWND_LOG_FROM_SS);
2046 }
2047 }
2048 } else {
2049 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
2050 sctp_log_cwnd(stcb, net, net->net_ack,
2051 SCTP_CWND_LOG_NOADV_SS);
2052 }
2053 }
2054 } else {
2055 measure_rtt(net);
2056
2057 /*
2058 * In dangerous area, increase slowly. In theory this is
2059 * net->cwnd += alpha / net->cwnd
2060 */
2061 /* What is snd_cwnd_cnt?? */
2062 if (((net->partial_bytes_acked / net->mtu * net->cc_mod.htcp_ca.alpha) >> 7) * net->mtu >= net->cwnd) {
2063 /*-
2064 * Does SCTP have a cwnd clamp?
2065 * if (net->snd_cwnd < net->snd_cwnd_clamp) - Nope (RRS).
2066 */
2067 net->cwnd += net->mtu;
2068 net->partial_bytes_acked = 0;
2069 htcp_alpha_update(&net->cc_mod.htcp_ca);
2070 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2071 sctp_log_cwnd(stcb, net, net->mtu,
2072 SCTP_CWND_LOG_FROM_CA);
2073 }
2074 } else {
2075 net->partial_bytes_acked += net->net_ack;
2076 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
2077 sctp_log_cwnd(stcb, net, net->net_ack,
2078 SCTP_CWND_LOG_NOADV_CA);
2079 }
2080 }
2081
2082 net->cc_mod.htcp_ca.bytes_acked = net->mtu;
2083 }
2084 }
2085
2086 #ifdef SCTP_NOT_USED
2087 /* Lower bound on congestion window. */
2088 static uint32_t
2089 htcp_min_cwnd(struct sctp_tcb *stcb, struct sctp_nets *net)
2090 {
2091 return (net->ssthresh);
2092 }
2093
2094 #endif
2095
2096 static void
2097 htcp_init(struct sctp_nets *net)
2098 {
2099 memset(&net->cc_mod.htcp_ca, 0, sizeof(struct htcp));
2100 net->cc_mod.htcp_ca.alpha = ALPHA_BASE;
2101 net->cc_mod.htcp_ca.beta = BETA_MIN;
2102 net->cc_mod.htcp_ca.bytes_acked = net->mtu;
2103 net->cc_mod.htcp_ca.last_cong = sctp_get_tick_count();
2104 }
2105
2106 static void
2107 sctp_htcp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net)
2108 {
2109 /*
2110 * We take the max of the burst limit times a MTU or the
2111 * INITIAL_CWND. We then limit this to 4 MTU's of sending.
2112 */
2113 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
2114 net->ssthresh = stcb->asoc.peers_rwnd;
2115 htcp_init(net);
2116
2117 if (SCTP_BASE_SYSCTL(sctp_logging_level) & (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) {
2118 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION);
2119 }
2120 }
2121
2122 static void
2123 sctp_htcp_cwnd_update_after_sack(struct sctp_tcb *stcb,
2124 struct sctp_association *asoc,
2125 int accum_moved, int reneged_all SCTP_UNUSED, int will_exit)
2126 {
2127 struct sctp_nets *net;
2128
2129 /******************************/
2130 /* update cwnd and Early FR */
2131 /******************************/
2132 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
2133
2134 #ifdef JANA_CMT_FAST_RECOVERY
2135 /*
2136 * CMT fast recovery code. Need to debug.
2137 */
2138 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
2139 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) ||
2140 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) {
2141 net->will_exit_fast_recovery = 1;
2142 }
2143 }
2144 #endif
2145 /* if nothing was acked on this destination skip it */
2146 if (net->net_ack == 0) {
2147 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
2148 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
2149 }
2150 continue;
2151 }
2152 #ifdef JANA_CMT_FAST_RECOVERY
2153 /*
2154 * CMT fast recovery code
2155 */
2156 /*
2157 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery
2158 * && net->will_exit_fast_recovery == 0) { @@@ Do something
2159 * } else if (sctp_cmt_on_off == 0 &&
2160 * asoc->fast_retran_loss_recovery && will_exit == 0) {
2161 */
2162 #endif
2163
2164 if (asoc->fast_retran_loss_recovery &&
2165 will_exit == 0 &&
2166 (asoc->sctp_cmt_on_off == 0)) {
2167 /*
2168 * If we are in loss recovery we skip any cwnd
2169 * update
2170 */
2171 return;
2172 }
2173 /*
2174 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
2175 * moved.
2176 */
2177 if (accum_moved ||
2178 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) {
2179 htcp_cong_avoid(stcb, net);
2180 measure_achieved_throughput(net);
2181 } else {
2182 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
2183 sctp_log_cwnd(stcb, net, net->mtu,
2184 SCTP_CWND_LOG_NO_CUMACK);
2185 }
2186 }
2187 }
2188 }
2189
2190 static void
2191 sctp_htcp_cwnd_update_after_fr(struct sctp_tcb *stcb,
2192 struct sctp_association *asoc)
2193 {
2194 struct sctp_nets *net;
2195
2196 /*
2197 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) &&
2198 * (net->fast_retran_loss_recovery == 0)))
2199 */
2200 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
2201 if ((asoc->fast_retran_loss_recovery == 0) ||
2202 (asoc->sctp_cmt_on_off > 0)) {
2203 /* out of a RFC2582 Fast recovery window? */
2204 if (net->net_ack > 0) {
2205 /*
2206 * per section 7.2.3, are there any
2207 * destinations that had a fast retransmit
2208 * to them. If so what we need to do is
2209 * adjust ssthresh and cwnd.
2210 */
2211 struct sctp_tmit_chunk *lchk;
2212 int old_cwnd = net->cwnd;
2213
2214 /* JRS - reset as if state were changed */
2215 htcp_reset(&net->cc_mod.htcp_ca);
2216 net->ssthresh = htcp_recalc_ssthresh(net);
2217 net->cwnd = net->ssthresh;
2218 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2219 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
2220 SCTP_CWND_LOG_FROM_FR);
2221 }
2222 lchk = TAILQ_FIRST(&asoc->send_queue);
2223
2224 net->partial_bytes_acked = 0;
2225 /* Turn on fast recovery window */
2226 asoc->fast_retran_loss_recovery = 1;
2227 if (lchk == NULL) {
2228 /* Mark end of the window */
2229 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
2230 } else {
2231 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
2232 }
2233
2234 /*
2235 * CMT fast recovery -- per destination
2236 * recovery variable.
2237 */
2238 net->fast_retran_loss_recovery = 1;
2239
2240 if (lchk == NULL) {
2241 /* Mark end of the window */
2242 net->fast_recovery_tsn = asoc->sending_seq - 1;
2243 } else {
2244 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
2245 }
2246
2247 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
2248 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
2249 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
2250 stcb->sctp_ep, stcb, net);
2251 }
2252 } else if (net->net_ack > 0) {
2253 /*
2254 * Mark a peg that we WOULD have done a cwnd
2255 * reduction but RFC2582 prevented this action.
2256 */
2257 SCTP_STAT_INCR(sctps_fastretransinrtt);
2258 }
2259 }
2260 }
2261
2262 static void
2263 sctp_htcp_cwnd_update_after_timeout(struct sctp_tcb *stcb,
2264 struct sctp_nets *net)
2265 {
2266 int old_cwnd = net->cwnd;
2267
2268 /* JRS - reset as if the state were being changed to timeout */
2269 htcp_reset(&net->cc_mod.htcp_ca);
2270 net->ssthresh = htcp_recalc_ssthresh(net);
2271 net->cwnd = net->mtu;
2272 net->partial_bytes_acked = 0;
2273 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2274 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX);
2275 }
2276 }
2277
2278 static void
2279 sctp_htcp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb,
2280 struct sctp_nets *net, int in_window, int num_pkt_lost SCTP_UNUSED)
2281 {
2282 int old_cwnd;
2283
2284 old_cwnd = net->cwnd;
2285
2286 /* JRS - reset hctp as if state changed */
2287 if (in_window == 0) {
2288 htcp_reset(&net->cc_mod.htcp_ca);
2289 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
2290 net->ssthresh = htcp_recalc_ssthresh(net);
2291 if (net->ssthresh < net->mtu) {
2292 net->ssthresh = net->mtu;
2293 /* here back off the timer as well, to slow us down */
2294 net->RTO <<= 1;
2295 }
2296 net->cwnd = net->ssthresh;
2297 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
2298 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
2299 }
2300 }
2301 }
2302
2303 struct sctp_cc_functions sctp_cc_functions[] = {
2304 {
2305 .sctp_set_initial_cc_param = sctp_set_initial_cc_param,
2306 .sctp_cwnd_update_after_sack = sctp_cwnd_update_after_sack,
2307 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common,
2308 .sctp_cwnd_update_after_fr = sctp_cwnd_update_after_fr,
2309 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout,
2310 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_after_ecn_echo,
2311 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped,
2312 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output,
2313 },
2314 {
2315 .sctp_set_initial_cc_param = sctp_set_initial_cc_param,
2316 .sctp_cwnd_update_after_sack = sctp_hs_cwnd_update_after_sack,
2317 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common,
2318 .sctp_cwnd_update_after_fr = sctp_hs_cwnd_update_after_fr,
2319 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout,
2320 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_after_ecn_echo,
2321 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped,
2322 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output,
2323 },
2324 {
2325 .sctp_set_initial_cc_param = sctp_htcp_set_initial_cc_param,
2326 .sctp_cwnd_update_after_sack = sctp_htcp_cwnd_update_after_sack,
2327 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common,
2328 .sctp_cwnd_update_after_fr = sctp_htcp_cwnd_update_after_fr,
2329 .sctp_cwnd_update_after_timeout = sctp_htcp_cwnd_update_after_timeout,
2330 .sctp_cwnd_update_after_ecn_echo = sctp_htcp_cwnd_update_after_ecn_echo,
2331 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped,
2332 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output,
2333 },
2334 {
2335 .sctp_set_initial_cc_param = sctp_set_rtcc_initial_cc_param,
2336 .sctp_cwnd_update_after_sack = sctp_cwnd_update_rtcc_after_sack,
2337 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common,
2338 .sctp_cwnd_update_after_fr = sctp_cwnd_update_after_fr,
2339 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout,
2340 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_rtcc_after_ecn_echo,
2341 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped,
2342 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output,
2343 .sctp_cwnd_update_packet_transmitted = sctp_cwnd_update_rtcc_packet_transmitted,
2344 .sctp_cwnd_update_tsn_acknowledged = sctp_cwnd_update_rtcc_tsn_acknowledged,
2345 .sctp_cwnd_new_transmission_begins = sctp_cwnd_new_rtcc_transmission_begins,
2346 .sctp_cwnd_prepare_net_for_sack = sctp_cwnd_prepare_rtcc_net_for_sack,
2347 .sctp_cwnd_socket_option = sctp_cwnd_rtcc_socket_option,
2348 .sctp_rtt_calculated = sctp_rtt_rtcc_calculated
2349 }
2350 };
Cache object: d1e7613ce990a59e27211becdf94bfb0
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