1/*-
2 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 *
7 * a) Redistributions of source code must retain the above copyright notice,
8 * this list of conditions and the following disclaimer.
9 *
10 * b) Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the distribution.
13 *
14 * c) Neither the name of Cisco Systems, Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived
16 * from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
20 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
28 * THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <netinet/sctp_os.h>
32#include <netinet/sctp_var.h>
33#include <netinet/sctp_sysctl.h>
34#include <netinet/sctp_pcb.h>
35#include <netinet/sctp_header.h>
36#include <netinet/sctputil.h>
37#include <netinet/sctp_output.h>
38#include <netinet/sctp_input.h>
39#include <netinet/sctp_indata.h>
40#include <netinet/sctp_uio.h>
41#include <netinet/sctp_timer.h>
42#include <netinet/sctp_auth.h>
43#include <netinet/sctp_asconf.h>
44#include <netinet/sctp_cc_functions.h>
45#include <sys/cdefs.h>
46__FBSDID("$FreeBSD: head/sys/netinet/sctp_cc_functions.c 179783 2008-06-14 07:58:05Z rrs $");
47void
48sctp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net)
49{
50 /*
51 * We take the max of the burst limit times a MTU or the
52 * INITIAL_CWND. We then limit this to 4 MTU's of sending. cwnd must
53 * be at least 2 MTU.
54 */
55 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
56 net->ssthresh = stcb->asoc.peers_rwnd;
57
58 if (SCTP_BASE_SYSCTL(sctp_logging_level) & (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) {
59 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION);
60 }
61}
62
63void
64sctp_cwnd_update_after_fr(struct sctp_tcb *stcb,
65 struct sctp_association *asoc)
66{
67 struct sctp_nets *net;
68
69 /*-
70 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off == 1) &&
71 * (net->fast_retran_loss_recovery == 0)))
72 */
73 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
74 if ((asoc->fast_retran_loss_recovery == 0) || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 1)) {
75 /* out of a RFC2582 Fast recovery window? */
76 if (net->net_ack > 0) {
77 /*
78 * per section 7.2.3, are there any
79 * destinations that had a fast retransmit
80 * to them. If so what we need to do is
81 * adjust ssthresh and cwnd.
82 */
83 struct sctp_tmit_chunk *lchk;
84 int old_cwnd = net->cwnd;
85
86 net->ssthresh = net->cwnd / 2;
87 if (net->ssthresh < (net->mtu * 2)) {
88 net->ssthresh = 2 * net->mtu;
89 }
90 net->cwnd = net->ssthresh;
91 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
92 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
93 SCTP_CWND_LOG_FROM_FR);
94 }
95 lchk = TAILQ_FIRST(&asoc->send_queue);
96
97 net->partial_bytes_acked = 0;
98 /* Turn on fast recovery window */
99 asoc->fast_retran_loss_recovery = 1;
100 if (lchk == NULL) {
101 /* Mark end of the window */
102 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
103 } else {
104 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
105 }
106
107 /*
108 * CMT fast recovery -- per destination
109 * recovery variable.
110 */
111 net->fast_retran_loss_recovery = 1;
112
113 if (lchk == NULL) {
114 /* Mark end of the window */
115 net->fast_recovery_tsn = asoc->sending_seq - 1;
116 } else {
117 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
118 }
119
120 /*
121 * Disable Nonce Sum Checking and store the
122 * resync tsn
123 */
124 asoc->nonce_sum_check = 0;
125 asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
126
127 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
128 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
129 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
130 stcb->sctp_ep, stcb, net);
131 }
132 } else if (net->net_ack > 0) {
133 /*
134 * Mark a peg that we WOULD have done a cwnd
135 * reduction but RFC2582 prevented this action.
136 */
137 SCTP_STAT_INCR(sctps_fastretransinrtt);
138 }
139 }
140}
141
142void
143sctp_cwnd_update_after_sack(struct sctp_tcb *stcb,
144 struct sctp_association *asoc,
145 int accum_moved, int reneged_all, int will_exit)
146{
147 struct sctp_nets *net;
148
149 /******************************/
150 /* update cwnd and Early FR */
151 /******************************/
152 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
153
154#ifdef JANA_CMT_FAST_RECOVERY
155 /*
156 * CMT fast recovery code. Need to debug.
157 */
158 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
159 if (compare_with_wrap(asoc->last_acked_seq,
160 net->fast_recovery_tsn, MAX_TSN) ||
161 (asoc->last_acked_seq == net->fast_recovery_tsn) ||
162 compare_with_wrap(net->pseudo_cumack, net->fast_recovery_tsn, MAX_TSN) ||
163 (net->pseudo_cumack == net->fast_recovery_tsn)) {
164 net->will_exit_fast_recovery = 1;
165 }
166 }
167#endif
168 if (SCTP_BASE_SYSCTL(sctp_early_fr)) {
169 /*
170 * So, first of all do we need to have a Early FR
171 * timer running?
172 */
173 if (((TAILQ_FIRST(&asoc->sent_queue)) &&
174 (net->ref_count > 1) &&
175 (net->flight_size < net->cwnd)) ||
176 (reneged_all)) {
177 /*
178 * yes, so in this case stop it if its
179 * running, and then restart it. Reneging
180 * all is a special case where we want to
181 * run the Early FR timer and then force the
182 * last few unacked to be sent, causing us
183 * to illicit a sack with gaps to force out
184 * the others.
185 */
186 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
187 SCTP_STAT_INCR(sctps_earlyfrstpidsck2);
188 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
189 SCTP_FROM_SCTP_INDATA + SCTP_LOC_20);
190 }
191 SCTP_STAT_INCR(sctps_earlyfrstrid);
192 sctp_timer_start(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net);
193 } else {
194 /* No, stop it if its running */
195 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
196 SCTP_STAT_INCR(sctps_earlyfrstpidsck3);
197 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
198 SCTP_FROM_SCTP_INDATA + SCTP_LOC_21);
199 }
200 }
201 }
202 /* if nothing was acked on this destination skip it */
203 if (net->net_ack == 0) {
204 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
205 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
206 }
207 continue;
208 }
209 if (net->net_ack2 > 0) {
210 /*
211 * Karn's rule applies to clearing error count, this
212 * is optional.
213 */
214 net->error_count = 0;
215 if ((net->dest_state & SCTP_ADDR_NOT_REACHABLE) ==
216 SCTP_ADDR_NOT_REACHABLE) {
217 /* addr came good */
218 net->dest_state &= ~SCTP_ADDR_NOT_REACHABLE;
219 net->dest_state |= SCTP_ADDR_REACHABLE;
220 sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
221 SCTP_RECEIVED_SACK, (void *)net, SCTP_SO_NOT_LOCKED);
222 /* now was it the primary? if so restore */
223 if (net->dest_state & SCTP_ADDR_WAS_PRIMARY) {
224 (void)sctp_set_primary_addr(stcb, (struct sockaddr *)NULL, net);
225 }
226 }
227 /*
228 * JRS 5/14/07 - If CMT PF is on and the destination
229 * is in PF state, set the destination to active
230 * state and set the cwnd to one or two MTU's based
231 * on whether PF1 or PF2 is being used.
232 *
233 * Should we stop any running T3 timer here?
234 */
235 if (SCTP_BASE_SYSCTL(sctp_cmt_on_off) &&
236 SCTP_BASE_SYSCTL(sctp_cmt_pf) &&
237 ((net->dest_state & SCTP_ADDR_PF) == SCTP_ADDR_PF)) {
238 net->dest_state &= ~SCTP_ADDR_PF;
239 net->cwnd = net->mtu * SCTP_BASE_SYSCTL(sctp_cmt_pf);
240 SCTPDBG(SCTP_DEBUG_INDATA1, "Destination %p moved from PF to reachable with cwnd %d.\n",
241 net, net->cwnd);
242 /*
243 * Since the cwnd value is explicitly set,
244 * skip the code that updates the cwnd
245 * value.
246 */
247 goto skip_cwnd_update;
248 }
249 }
250#ifdef JANA_CMT_FAST_RECOVERY
251 /*
252 * CMT fast recovery code
253 */
254 /*
255 * if (sctp_cmt_on_off == 1 &&
256 * net->fast_retran_loss_recovery &&
257 * net->will_exit_fast_recovery == 0) { @@@ Do something }
258 * else if (sctp_cmt_on_off == 0 &&
259 * asoc->fast_retran_loss_recovery && will_exit == 0) {
260 */
261#endif
262
263 if (asoc->fast_retran_loss_recovery && will_exit == 0 && SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 0) {
264 /*
265 * If we are in loss recovery we skip any cwnd
266 * update
267 */
268 goto skip_cwnd_update;
269 }
270 /*
271 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
272 * moved.
273 */
274 if (accum_moved || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) && net->new_pseudo_cumack)) {
275 /* If the cumulative ack moved we can proceed */
276 if (net->cwnd <= net->ssthresh) {
277 /* We are in slow start */
278 if (net->flight_size + net->net_ack >= net->cwnd) {
279 if (net->net_ack > (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable))) {
280 net->cwnd += (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable));
281 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
282 sctp_log_cwnd(stcb, net, net->mtu,
283 SCTP_CWND_LOG_FROM_SS);
284 }
285 } else {
286 net->cwnd += net->net_ack;
287 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
288 sctp_log_cwnd(stcb, net, net->net_ack,
289 SCTP_CWND_LOG_FROM_SS);
290 }
291 }
292 } else {
293 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
294 sctp_log_cwnd(stcb, net, net->net_ack,
295 SCTP_CWND_LOG_NOADV_SS);
296 }
297 }
298 } else {
299 /* We are in congestion avoidance */
300 /*
301 * Add to pba
302 */
303 net->partial_bytes_acked += net->net_ack;
304
305 if ((net->flight_size + net->net_ack >= net->cwnd) &&
306 (net->partial_bytes_acked >= net->cwnd)) {
307 net->partial_bytes_acked -= net->cwnd;
308 net->cwnd += net->mtu;
309 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
310 sctp_log_cwnd(stcb, net, net->mtu,
311 SCTP_CWND_LOG_FROM_CA);
312 }
313 } else {
314 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
315 sctp_log_cwnd(stcb, net, net->net_ack,
316 SCTP_CWND_LOG_NOADV_CA);
317 }
318 }
319 }
320 } else {
321 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
322 sctp_log_cwnd(stcb, net, net->mtu,
323 SCTP_CWND_LOG_NO_CUMACK);
324 }
325 }
326skip_cwnd_update:
327 /*
328 * NOW, according to Karn's rule do we need to restore the
329 * RTO timer back? Check our net_ack2. If not set then we
330 * have a ambiguity.. i.e. all data ack'd was sent to more
331 * than one place.
332 */
333 if (net->net_ack2) {
334 /* restore any doubled timers */
335 net->RTO = ((net->lastsa >> 2) + net->lastsv) >> 1;
336 if (net->RTO < stcb->asoc.minrto) {
337 net->RTO = stcb->asoc.minrto;
338 }
339 if (net->RTO > stcb->asoc.maxrto) {
340 net->RTO = stcb->asoc.maxrto;
341 }
342 }
343 }
344}
345
346void
347sctp_cwnd_update_after_timeout(struct sctp_tcb *stcb, struct sctp_nets *net)
348{
349 int old_cwnd = net->cwnd;
350
351 net->ssthresh = max(net->cwnd / 2, 2 * net->mtu);
352 net->cwnd = net->mtu;
353 net->partial_bytes_acked = 0;
354
355 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
356 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX);
357 }
358}
359
360void
361sctp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net)
362{
363 int old_cwnd = net->cwnd;
364
365 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
366 net->ssthresh = net->cwnd / 2;
367 if (net->ssthresh < net->mtu) {
368 net->ssthresh = net->mtu;
369 /* here back off the timer as well, to slow us down */
370 net->RTO <<= 1;
371 }
372 net->cwnd = net->ssthresh;
373 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
374 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
375 }
376}
377
378void
379sctp_cwnd_update_after_packet_dropped(struct sctp_tcb *stcb,
380 struct sctp_nets *net, struct sctp_pktdrop_chunk *cp,
381 uint32_t * bottle_bw, uint32_t * on_queue)
382{
383 uint32_t bw_avail;
384 int rtt, incr;
385 int old_cwnd = net->cwnd;
386
387 /* need real RTT for this calc */
388 rtt = ((net->lastsa >> 2) + net->lastsv) >> 1;
389 /* get bottle neck bw */
390 *bottle_bw = ntohl(cp->bottle_bw);
391 /* and whats on queue */
392 *on_queue = ntohl(cp->current_onq);
393 /*
394 * adjust the on-queue if our flight is more it could be that the
395 * router has not yet gotten data "in-flight" to it
396 */
397 if (*on_queue < net->flight_size)
398 *on_queue = net->flight_size;
399 /* calculate the available space */
400 bw_avail = (*bottle_bw * rtt) / 1000;
401 if (bw_avail > *bottle_bw) {
402 /*
403 * Cap the growth to no more than the bottle neck. This can
404 * happen as RTT slides up due to queues. It also means if
405 * you have more than a 1 second RTT with a empty queue you
406 * will be limited to the bottle_bw per second no matter if
407 * other points have 1/2 the RTT and you could get more
408 * out...
409 */
410 bw_avail = *bottle_bw;
411 }
412 if (*on_queue > bw_avail) {
413 /*
414 * No room for anything else don't allow anything else to be
415 * "added to the fire".
416 */
417 int seg_inflight, seg_onqueue, my_portion;
418
419 net->partial_bytes_acked = 0;
420
421 /* how much are we over queue size? */
422 incr = *on_queue - bw_avail;
423 if (stcb->asoc.seen_a_sack_this_pkt) {
424 /*
425 * undo any cwnd adjustment that the sack might have
426 * made
427 */
428 net->cwnd = net->prev_cwnd;
429 }
430 /* Now how much of that is mine? */
431 seg_inflight = net->flight_size / net->mtu;
432 seg_onqueue = *on_queue / net->mtu;
433 my_portion = (incr * seg_inflight) / seg_onqueue;
434
435 /* Have I made an adjustment already */
436 if (net->cwnd > net->flight_size) {
437 /*
438 * for this flight I made an adjustment we need to
439 * decrease the portion by a share our previous
440 * adjustment.
441 */
442 int diff_adj;
443
444 diff_adj = net->cwnd - net->flight_size;
445 if (diff_adj > my_portion)
446 my_portion = 0;
447 else
448 my_portion -= diff_adj;
449 }
450 /*
451 * back down to the previous cwnd (assume we have had a sack
452 * before this packet). minus what ever portion of the
453 * overage is my fault.
454 */
455 net->cwnd -= my_portion;
456
457 /* we will NOT back down more than 1 MTU */
458 if (net->cwnd <= net->mtu) {
459 net->cwnd = net->mtu;
460 }
461 /* force into CA */
462 net->ssthresh = net->cwnd - 1;
463 } else {
464 /*
465 * Take 1/4 of the space left or max burst up .. whichever
466 * is less.
467 */
468 incr = min((bw_avail - *on_queue) >> 2,
469 stcb->asoc.max_burst * net->mtu);
470 net->cwnd += incr;
471 }
472 if (net->cwnd > bw_avail) {
473 /* We can't exceed the pipe size */
474 net->cwnd = bw_avail;
475 }
476 if (net->cwnd < net->mtu) {
477 /* We always have 1 MTU */
478 net->cwnd = net->mtu;
479 }
480 if (net->cwnd - old_cwnd != 0) {
481 /* log only changes */
482 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
483 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
484 SCTP_CWND_LOG_FROM_SAT);
485 }
486 }
487}
488
489void
490sctp_cwnd_update_after_output(struct sctp_tcb *stcb,
491 struct sctp_nets *net, int burst_limit)
492{
493 int old_cwnd = net->cwnd;
494
495 if (net->ssthresh < net->cwnd)
496 net->ssthresh = net->cwnd;
497 net->cwnd = (net->flight_size + (burst_limit * net->mtu));
498
499 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
500 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_BRST);
501 }
502}
503
504void
505sctp_cwnd_update_after_fr_timer(struct sctp_inpcb *inp,
506 struct sctp_tcb *stcb, struct sctp_nets *net)
507{
508 int old_cwnd = net->cwnd;
509
510 sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_EARLY_FR_TMR, SCTP_SO_NOT_LOCKED);
511 /*
512 * make a small adjustment to cwnd and force to CA.
513 */
514 if (net->cwnd > net->mtu)
515 /* drop down one MTU after sending */
516 net->cwnd -= net->mtu;
517 if (net->cwnd < net->ssthresh)
518 /* still in SS move to CA */
519 net->ssthresh = net->cwnd - 1;
520 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
521 sctp_log_cwnd(stcb, net, (old_cwnd - net->cwnd), SCTP_CWND_LOG_FROM_FR);
522 }
523}
524
525struct sctp_hs_raise_drop {
526 int32_t cwnd;
527 int32_t increase;
528 int32_t drop_percent;
529};
530
531#define SCTP_HS_TABLE_SIZE 73
532
533struct sctp_hs_raise_drop sctp_cwnd_adjust[SCTP_HS_TABLE_SIZE] = {
534 {38, 1, 50}, /* 0 */
535 {118, 2, 44}, /* 1 */
536 {221, 3, 41}, /* 2 */
537 {347, 4, 38}, /* 3 */
538 {495, 5, 37}, /* 4 */
539 {663, 6, 35}, /* 5 */
540 {851, 7, 34}, /* 6 */
541 {1058, 8, 33}, /* 7 */
542 {1284, 9, 32}, /* 8 */
543 {1529, 10, 31}, /* 9 */
544 {1793, 11, 30}, /* 10 */
545 {2076, 12, 29}, /* 11 */
546 {2378, 13, 28}, /* 12 */
547 {2699, 14, 28}, /* 13 */
548 {3039, 15, 27}, /* 14 */
549 {3399, 16, 27}, /* 15 */
550 {3778, 17, 26}, /* 16 */
551 {4177, 18, 26}, /* 17 */
552 {4596, 19, 25}, /* 18 */
553 {5036, 20, 25}, /* 19 */
554 {5497, 21, 24}, /* 20 */
555 {5979, 22, 24}, /* 21 */
556 {6483, 23, 23}, /* 22 */
557 {7009, 24, 23}, /* 23 */
558 {7558, 25, 22}, /* 24 */
559 {8130, 26, 22}, /* 25 */
560 {8726, 27, 22}, /* 26 */
561 {9346, 28, 21}, /* 27 */
562 {9991, 29, 21}, /* 28 */
563 {10661, 30, 21}, /* 29 */
564 {11358, 31, 20}, /* 30 */
565 {12082, 32, 20}, /* 31 */
566 {12834, 33, 20}, /* 32 */
567 {13614, 34, 19}, /* 33 */
568 {14424, 35, 19}, /* 34 */
569 {15265, 36, 19}, /* 35 */
570 {16137, 37, 19}, /* 36 */
571 {17042, 38, 18}, /* 37 */
572 {17981, 39, 18}, /* 38 */
573 {18955, 40, 18}, /* 39 */
574 {19965, 41, 17}, /* 40 */
575 {21013, 42, 17}, /* 41 */
576 {22101, 43, 17}, /* 42 */
577 {23230, 44, 17}, /* 43 */
578 {24402, 45, 16}, /* 44 */
579 {25618, 46, 16}, /* 45 */
580 {26881, 47, 16}, /* 46 */
581 {28193, 48, 16}, /* 47 */
582 {29557, 49, 15}, /* 48 */
583 {30975, 50, 15}, /* 49 */
584 {32450, 51, 15}, /* 50 */
585 {33986, 52, 15}, /* 51 */
586 {35586, 53, 14}, /* 52 */
587 {37253, 54, 14}, /* 53 */
588 {38992, 55, 14}, /* 54 */
589 {40808, 56, 14}, /* 55 */
590 {42707, 57, 13}, /* 56 */
591 {44694, 58, 13}, /* 57 */
592 {46776, 59, 13}, /* 58 */
593 {48961, 60, 13}, /* 59 */
594 {51258, 61, 13}, /* 60 */
595 {53677, 62, 12}, /* 61 */
596 {56230, 63, 12}, /* 62 */
597 {58932, 64, 12}, /* 63 */
598 {61799, 65, 12}, /* 64 */
599 {64851, 66, 11}, /* 65 */
600 {68113, 67, 11}, /* 66 */
601 {71617, 68, 11}, /* 67 */
602 {75401, 69, 10}, /* 68 */
603 {79517, 70, 10}, /* 69 */
604 {84035, 71, 10}, /* 70 */
605 {89053, 72, 10}, /* 71 */
606 {94717, 73, 9} /* 72 */
607};
608
609static void
610sctp_hs_cwnd_increase(struct sctp_tcb *stcb, struct sctp_nets *net)
611{
612 int cur_val, i, indx, incr;
613
614 cur_val = net->cwnd >> 10;
615 indx = SCTP_HS_TABLE_SIZE - 1;
616#ifdef SCTP_DEBUG
617 printf("HS CC CAlled.\n");
618#endif
619 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
620 /* normal mode */
621 if (net->net_ack > net->mtu) {
622 net->cwnd += net->mtu;
623 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
624 sctp_log_cwnd(stcb, net, net->mtu, SCTP_CWND_LOG_FROM_SS);
625 }
626 } else {
627 net->cwnd += net->net_ack;
628 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
629 sctp_log_cwnd(stcb, net, net->net_ack, SCTP_CWND_LOG_FROM_SS);
630 }
631 }
632 } else {
633 for (i = net->last_hs_used; i < SCTP_HS_TABLE_SIZE; i++) {
634 if (cur_val < sctp_cwnd_adjust[i].cwnd) {
635 indx = i;
636 break;
637 }
638 }
639 net->last_hs_used = indx;
640 incr = ((sctp_cwnd_adjust[indx].increase) << 10);
641 net->cwnd += incr;
642 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
643 sctp_log_cwnd(stcb, net, incr, SCTP_CWND_LOG_FROM_SS);
644 }
645 }
646}
647
648static void
649sctp_hs_cwnd_decrease(struct sctp_tcb *stcb, struct sctp_nets *net)
650{
651 int cur_val, i, indx;
652 int old_cwnd = net->cwnd;
653
654 cur_val = net->cwnd >> 10;
655 indx = net->last_hs_used;
656 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
657 /* normal mode */
658 net->ssthresh = net->cwnd / 2;
659 if (net->ssthresh < (net->mtu * 2)) {
660 net->ssthresh = 2 * net->mtu;
661 }
662 net->cwnd = net->ssthresh;
663 } else {
664 /* drop by the proper amount */
665 net->ssthresh = net->cwnd - (int)((net->cwnd / 100) *
666 sctp_cwnd_adjust[net->last_hs_used].drop_percent);
667 net->cwnd = net->ssthresh;
668 /* now where are we */
669 indx = net->last_hs_used;
670 cur_val = net->cwnd >> 10;
671 /* reset where we are in the table */
672 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
673 /* feel out of hs */
674 net->last_hs_used = 0;
675 } else {
676 for (i = indx; i >= 1; i--) {
677 if (cur_val > sctp_cwnd_adjust[i - 1].cwnd) {
678 break;
679 }
680 }
681 net->last_hs_used = indx;
682 }
683 }
684 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
685 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_FR);
686 }
687}
688
689void
690sctp_hs_cwnd_update_after_fr(struct sctp_tcb *stcb,
691 struct sctp_association *asoc)
692{
693 struct sctp_nets *net;
694
695 /*
696 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off == 1) &&
697 * (net->fast_retran_loss_recovery == 0)))
698 */
699 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
700 if ((asoc->fast_retran_loss_recovery == 0) || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 1)) {
701 /* out of a RFC2582 Fast recovery window? */
702 if (net->net_ack > 0) {
703 /*
704 * per section 7.2.3, are there any
705 * destinations that had a fast retransmit
706 * to them. If so what we need to do is
707 * adjust ssthresh and cwnd.
708 */
709 struct sctp_tmit_chunk *lchk;
710
711 sctp_hs_cwnd_decrease(stcb, net);
712
713 lchk = TAILQ_FIRST(&asoc->send_queue);
714
715 net->partial_bytes_acked = 0;
716 /* Turn on fast recovery window */
717 asoc->fast_retran_loss_recovery = 1;
718 if (lchk == NULL) {
719 /* Mark end of the window */
720 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
721 } else {
722 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
723 }
724
725 /*
726 * CMT fast recovery -- per destination
727 * recovery variable.
728 */
729 net->fast_retran_loss_recovery = 1;
730
731 if (lchk == NULL) {
732 /* Mark end of the window */
733 net->fast_recovery_tsn = asoc->sending_seq - 1;
734 } else {
735 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
736 }
737
738 /*
739 * Disable Nonce Sum Checking and store the
740 * resync tsn
741 */
742 asoc->nonce_sum_check = 0;
743 asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
744
745 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
746 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
747 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
748 stcb->sctp_ep, stcb, net);
749 }
750 } else if (net->net_ack > 0) {
751 /*
752 * Mark a peg that we WOULD have done a cwnd
753 * reduction but RFC2582 prevented this action.
754 */
755 SCTP_STAT_INCR(sctps_fastretransinrtt);
756 }
757 }
758}
759
760void
761sctp_hs_cwnd_update_after_sack(struct sctp_tcb *stcb,
762 struct sctp_association *asoc,
763 int accum_moved, int reneged_all, int will_exit)
764{
765 struct sctp_nets *net;
766
767 /******************************/
768 /* update cwnd and Early FR */
769 /******************************/
770 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
771
772#ifdef JANA_CMT_FAST_RECOVERY
773 /*
774 * CMT fast recovery code. Need to debug.
775 */
776 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
777 if (compare_with_wrap(asoc->last_acked_seq,
778 net->fast_recovery_tsn, MAX_TSN) ||
779 (asoc->last_acked_seq == net->fast_recovery_tsn) ||
780 compare_with_wrap(net->pseudo_cumack, net->fast_recovery_tsn, MAX_TSN) ||
781 (net->pseudo_cumack == net->fast_recovery_tsn)) {
782 net->will_exit_fast_recovery = 1;
783 }
784 }
785#endif
786 if (SCTP_BASE_SYSCTL(sctp_early_fr)) {
787 /*
788 * So, first of all do we need to have a Early FR
789 * timer running?
790 */
791 if (((TAILQ_FIRST(&asoc->sent_queue)) &&
792 (net->ref_count > 1) &&
793 (net->flight_size < net->cwnd)) ||
794 (reneged_all)) {
795 /*
796 * yes, so in this case stop it if its
797 * running, and then restart it. Reneging
798 * all is a special case where we want to
799 * run the Early FR timer and then force the
800 * last few unacked to be sent, causing us
801 * to illicit a sack with gaps to force out
802 * the others.
803 */
804 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
805 SCTP_STAT_INCR(sctps_earlyfrstpidsck2);
806 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
807 SCTP_FROM_SCTP_INDATA + SCTP_LOC_20);
808 }
809 SCTP_STAT_INCR(sctps_earlyfrstrid);
810 sctp_timer_start(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net);
811 } else {
812 /* No, stop it if its running */
813 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
814 SCTP_STAT_INCR(sctps_earlyfrstpidsck3);
815 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
816 SCTP_FROM_SCTP_INDATA + SCTP_LOC_21);
817 }
818 }
819 }
820 /* if nothing was acked on this destination skip it */
821 if (net->net_ack == 0) {
822 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
823 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
824 }
825 continue;
826 }
827 if (net->net_ack2 > 0) {
828 /*
829 * Karn's rule applies to clearing error count, this
830 * is optional.
831 */
832 net->error_count = 0;
833 if ((net->dest_state & SCTP_ADDR_NOT_REACHABLE) ==
834 SCTP_ADDR_NOT_REACHABLE) {
835 /* addr came good */
836 net->dest_state &= ~SCTP_ADDR_NOT_REACHABLE;
837 net->dest_state |= SCTP_ADDR_REACHABLE;
838 sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
839 SCTP_RECEIVED_SACK, (void *)net, SCTP_SO_NOT_LOCKED);
840 /* now was it the primary? if so restore */
841 if (net->dest_state & SCTP_ADDR_WAS_PRIMARY) {
842 (void)sctp_set_primary_addr(stcb, (struct sockaddr *)NULL, net);
843 }
844 }
845 /*
846 * JRS 5/14/07 - If CMT PF is on and the destination
847 * is in PF state, set the destination to active
848 * state and set the cwnd to one or two MTU's based
849 * on whether PF1 or PF2 is being used.
850 *
851 * Should we stop any running T3 timer here?
852 */
853 if (SCTP_BASE_SYSCTL(sctp_cmt_on_off) &&
854 SCTP_BASE_SYSCTL(sctp_cmt_pf) &&
855 ((net->dest_state & SCTP_ADDR_PF) == SCTP_ADDR_PF)) {
856 net->dest_state &= ~SCTP_ADDR_PF;
857 net->cwnd = net->mtu * SCTP_BASE_SYSCTL(sctp_cmt_pf);
858 SCTPDBG(SCTP_DEBUG_INDATA1, "Destination %p moved from PF to reachable with cwnd %d.\n",
859 net, net->cwnd);
860 /*
861 * Since the cwnd value is explicitly set,
862 * skip the code that updates the cwnd
863 * value.
864 */
865 goto skip_cwnd_update;
866 }
867 }
868#ifdef JANA_CMT_FAST_RECOVERY
869 /*
870 * CMT fast recovery code
871 */
872 /*
873 * if (sctp_cmt_on_off == 1 &&
874 * net->fast_retran_loss_recovery &&
875 * net->will_exit_fast_recovery == 0) { @@@ Do something }
876 * else if (sctp_cmt_on_off == 0 &&
877 * asoc->fast_retran_loss_recovery && will_exit == 0) {
878 */
879#endif
880
881 if (asoc->fast_retran_loss_recovery && will_exit == 0 && SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 0) {
882 /*
883 * If we are in loss recovery we skip any cwnd
884 * update
885 */
886 goto skip_cwnd_update;
887 }
888 /*
889 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
890 * moved.
891 */
892 if (accum_moved || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) && net->new_pseudo_cumack)) {
893 /* If the cumulative ack moved we can proceed */
894 if (net->cwnd <= net->ssthresh) {
895 /* We are in slow start */
896 if (net->flight_size + net->net_ack >= net->cwnd) {
897
898 sctp_hs_cwnd_increase(stcb, net);
899
900 } else {
901 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
902 sctp_log_cwnd(stcb, net, net->net_ack,
903 SCTP_CWND_LOG_NOADV_SS);
904 }
905 }
906 } else {
907 /* We are in congestion avoidance */
908 net->partial_bytes_acked += net->net_ack;
909 if ((net->flight_size + net->net_ack >= net->cwnd) &&
910 (net->partial_bytes_acked >= net->cwnd)) {
911 net->partial_bytes_acked -= net->cwnd;
912 net->cwnd += net->mtu;
913 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
914 sctp_log_cwnd(stcb, net, net->mtu,
915 SCTP_CWND_LOG_FROM_CA);
916 }
917 } else {
918 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
919 sctp_log_cwnd(stcb, net, net->net_ack,
920 SCTP_CWND_LOG_NOADV_CA);
921 }
922 }
923 }
924 } else {
925 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
926 sctp_log_cwnd(stcb, net, net->mtu,
927 SCTP_CWND_LOG_NO_CUMACK);
928 }
929 }
930skip_cwnd_update:
931 /*
932 * NOW, according to Karn's rule do we need to restore the
933 * RTO timer back? Check our net_ack2. If not set then we
934 * have a ambiguity.. i.e. all data ack'd was sent to more
935 * than one place.
936 */
937 if (net->net_ack2) {
938 /* restore any doubled timers */
939 net->RTO = ((net->lastsa >> 2) + net->lastsv) >> 1;
940 if (net->RTO < stcb->asoc.minrto) {
941 net->RTO = stcb->asoc.minrto;
942 }
943 if (net->RTO > stcb->asoc.maxrto) {
944 net->RTO = stcb->asoc.maxrto;
945 }
946 }
947 }
948}
949
950
951/*
952 * H-TCP congestion control. The algorithm is detailed in:
953 * R.N.Shorten, D.J.Leith:
954 * "H-TCP: TCP for high-speed and long-distance networks"
955 * Proc. PFLDnet, Argonne, 2004.
956 * http://www.hamilton.ie/net/htcp3.pdf
957 */
958
959
960static int use_rtt_scaling = 1;
961static int use_bandwidth_switch = 1;
962
963static inline int
964between(uint32_t seq1, uint32_t seq2, uint32_t seq3)
965{
966 return seq3 - seq2 >= seq1 - seq2;
967}
968
969static inline uint32_t
970htcp_cong_time(struct htcp *ca)
971{
972 return sctp_get_tick_count() - ca->last_cong;
973}
974
975static inline uint32_t
976htcp_ccount(struct htcp *ca)
977{
978 return htcp_cong_time(ca) / ca->minRTT;
979}
980
981static inline void
982htcp_reset(struct htcp *ca)
983{
984 ca->undo_last_cong = ca->last_cong;
985 ca->undo_maxRTT = ca->maxRTT;
986 ca->undo_old_maxB = ca->old_maxB;
987 ca->last_cong = sctp_get_tick_count();
988}
989
990#ifdef SCTP_NOT_USED
991
992static uint32_t
993htcp_cwnd_undo(struct sctp_tcb *stcb, struct sctp_nets *net)
994{
995 net->htcp_ca.last_cong = net->htcp_ca.undo_last_cong;
996 net->htcp_ca.maxRTT = net->htcp_ca.undo_maxRTT;
997 net->htcp_ca.old_maxB = net->htcp_ca.undo_old_maxB;
998 return max(net->cwnd, ((net->ssthresh / net->mtu << 7) / net->htcp_ca.beta) * net->mtu);
999}
1000
1001#endif
1002
1003static inline void
1004measure_rtt(struct sctp_tcb *stcb, struct sctp_nets *net)
1005{
1006 uint32_t srtt = net->lastsa >> 3;
1007
1008 /* keep track of minimum RTT seen so far, minRTT is zero at first */
1009 if (net->htcp_ca.minRTT > srtt || !net->htcp_ca.minRTT)
1010 net->htcp_ca.minRTT = srtt;
1011
1012 /* max RTT */
1013 if (net->fast_retran_ip == 0 && net->ssthresh < 0xFFFF && htcp_ccount(&net->htcp_ca) > 3) {
1014 if (net->htcp_ca.maxRTT < net->htcp_ca.minRTT)
1015 net->htcp_ca.maxRTT = net->htcp_ca.minRTT;
1016 if (net->htcp_ca.maxRTT < srtt && srtt <= net->htcp_ca.maxRTT + MSEC_TO_TICKS(20))
1017 net->htcp_ca.maxRTT = srtt;
1018 }
1019}
1020
1021static void
1022measure_achieved_throughput(struct sctp_tcb *stcb, struct sctp_nets *net)
1023{
1024 uint32_t now = sctp_get_tick_count();
1025
1026 if (net->fast_retran_ip == 0)
1027 net->htcp_ca.bytes_acked = net->net_ack;
1028
1029 if (!use_bandwidth_switch)
1030 return;
1031
1032 /* achieved throughput calculations */
1033 /* JRS - not 100% sure of this statement */
1034 if (net->fast_retran_ip == 1) {
1035 net->htcp_ca.bytecount = 0;
1036 net->htcp_ca.lasttime = now;
1037 return;
1038 }
1039 net->htcp_ca.bytecount += net->net_ack;
1040
1041 if (net->htcp_ca.bytecount >= net->cwnd - ((net->htcp_ca.alpha >> 7 ? : 1) * net->mtu)
1042 && now - net->htcp_ca.lasttime >= net->htcp_ca.minRTT
1043 && net->htcp_ca.minRTT > 0) {
1044 uint32_t cur_Bi = net->htcp_ca.bytecount / net->mtu * hz / (now - net->htcp_ca.lasttime);
1045
1046 if (htcp_ccount(&net->htcp_ca) <= 3) {
1047 /* just after backoff */
1048 net->htcp_ca.minB = net->htcp_ca.maxB = net->htcp_ca.Bi = cur_Bi;
1049 } else {
1050 net->htcp_ca.Bi = (3 * net->htcp_ca.Bi + cur_Bi) / 4;
1051 if (net->htcp_ca.Bi > net->htcp_ca.maxB)
1052 net->htcp_ca.maxB = net->htcp_ca.Bi;
1053 if (net->htcp_ca.minB > net->htcp_ca.maxB)
1054 net->htcp_ca.minB = net->htcp_ca.maxB;
1055 }
1056 net->htcp_ca.bytecount = 0;
1057 net->htcp_ca.lasttime = now;
1058 }
1059}
1060
1061static inline void
1062htcp_beta_update(struct htcp *ca, uint32_t minRTT, uint32_t maxRTT)
1063{
1064 if (use_bandwidth_switch) {
1065 uint32_t maxB = ca->maxB;
1066 uint32_t old_maxB = ca->old_maxB;
1067
1068 ca->old_maxB = ca->maxB;
1069
1070 if (!between(5 * maxB, 4 * old_maxB, 6 * old_maxB)) {
1071 ca->beta = BETA_MIN;
1072 ca->modeswitch = 0;
1073 return;
1074 }
1075 }
1076 if (ca->modeswitch && minRTT > (uint32_t) MSEC_TO_TICKS(10) && maxRTT) {
1077 ca->beta = (minRTT << 7) / maxRTT;
1078 if (ca->beta < BETA_MIN)
1079 ca->beta = BETA_MIN;
1080 else if (ca->beta > BETA_MAX)
1081 ca->beta = BETA_MAX;
1082 } else {
1083 ca->beta = BETA_MIN;
1084 ca->modeswitch = 1;
1085 }
1086}
1087
1088static inline void
1089htcp_alpha_update(struct htcp *ca)
1090{
1091 uint32_t minRTT = ca->minRTT;
1092 uint32_t factor = 1;
1093 uint32_t diff = htcp_cong_time(ca);
1094
1095 if (diff > (uint32_t) hz) {
1096 diff -= hz;
1097 factor = 1 + (10 * diff + ((diff / 2) * (diff / 2) / hz)) / hz;
1098 }
1099 if (use_rtt_scaling && minRTT) {
1100 uint32_t scale = (hz << 3) / (10 * minRTT);
1101
1102 scale = min(max(scale, 1U << 2), 10U << 3); /* clamping ratio to
1103 * interval [0.5,10]<<3 */
1104 factor = (factor << 3) / scale;
1105 if (!factor)
1106 factor = 1;
1107 }
1108 ca->alpha = 2 * factor * ((1 << 7) - ca->beta);
1109 if (!ca->alpha)
1110 ca->alpha = ALPHA_BASE;
1111}
1112
1113/* After we have the rtt data to calculate beta, we'd still prefer to wait one
1114 * rtt before we adjust our beta to ensure we are working from a consistent
1115 * data.
1116 *
1117 * This function should be called when we hit a congestion event since only at
1118 * that point do we really have a real sense of maxRTT (the queues en route
1119 * were getting just too full now).
1120 */
1121static void
1122htcp_param_update(struct sctp_tcb *stcb, struct sctp_nets *net)
1123{
1124 uint32_t minRTT = net->htcp_ca.minRTT;
1125 uint32_t maxRTT = net->htcp_ca.maxRTT;
1126
1127 htcp_beta_update(&net->htcp_ca, minRTT, maxRTT);
1128 htcp_alpha_update(&net->htcp_ca);
1129
1130 /*
1131 * add slowly fading memory for maxRTT to accommodate routing
1132 * changes etc
1133 */
1134 if (minRTT > 0 && maxRTT > minRTT)
1135 net->htcp_ca.maxRTT = minRTT + ((maxRTT - minRTT) * 95) / 100;
1136}
1137
1138static uint32_t
1139htcp_recalc_ssthresh(struct sctp_tcb *stcb, struct sctp_nets *net)
1140{
1141 htcp_param_update(stcb, net);
1142 return max(((net->cwnd / net->mtu * net->htcp_ca.beta) >> 7) * net->mtu, 2U * net->mtu);
1143}
1144
1145static void
1146htcp_cong_avoid(struct sctp_tcb *stcb, struct sctp_nets *net)
1147{
1148 /*-
1149 * How to handle these functions?
1150 * if (!tcp_is_cwnd_limited(sk, in_flight)) RRS - good question.
1151 * return;
1152 */
1153 if (net->cwnd <= net->ssthresh) {
1154 /* We are in slow start */
1155 if (net->flight_size + net->net_ack >= net->cwnd) {
1156 if (net->net_ack > (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable))) {
1157 net->cwnd += (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable));
1158 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1159 sctp_log_cwnd(stcb, net, net->mtu,
1160 SCTP_CWND_LOG_FROM_SS);
1161 }
1162 } else {
1163 net->cwnd += net->net_ack;
1164 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1165 sctp_log_cwnd(stcb, net, net->net_ack,
1166 SCTP_CWND_LOG_FROM_SS);
1167 }
1168 }
1169 } else {
1170 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1171 sctp_log_cwnd(stcb, net, net->net_ack,
1172 SCTP_CWND_LOG_NOADV_SS);
1173 }
1174 }
1175 } else {
1176 measure_rtt(stcb, net);
1177
1178 /*
1179 * In dangerous area, increase slowly. In theory this is
1180 * net->cwnd += alpha / net->cwnd
1181 */
1182 /* What is snd_cwnd_cnt?? */
1183 if (((net->partial_bytes_acked / net->mtu * net->htcp_ca.alpha) >> 7) * net->mtu >= net->cwnd) {
1184 /*-
1185 * Does SCTP have a cwnd clamp?
1186 * if (net->snd_cwnd < net->snd_cwnd_clamp) - Nope (RRS).
1187 */
1188 net->cwnd += net->mtu;
1189 net->partial_bytes_acked = 0;
1190 htcp_alpha_update(&net->htcp_ca);
1191 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1192 sctp_log_cwnd(stcb, net, net->mtu,
1193 SCTP_CWND_LOG_FROM_CA);
1194 }
1195 } else {
1196 net->partial_bytes_acked += net->net_ack;
1197 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1198 sctp_log_cwnd(stcb, net, net->net_ack,
1199 SCTP_CWND_LOG_NOADV_CA);
1200 }
1201 }
1202
1203 net->htcp_ca.bytes_acked = net->mtu;
1204 }
1205}
1206
1207#ifdef SCTP_NOT_USED
1208/* Lower bound on congestion window. */
1209static uint32_t
1210htcp_min_cwnd(struct sctp_tcb *stcb, struct sctp_nets *net)
1211{
1212 return net->ssthresh;
1213}
1214
1215#endif
1216
1217static void
1218htcp_init(struct sctp_tcb *stcb, struct sctp_nets *net)
1219{
1220 memset(&net->htcp_ca, 0, sizeof(struct htcp));
1221 net->htcp_ca.alpha = ALPHA_BASE;
1222 net->htcp_ca.beta = BETA_MIN;
1223 net->htcp_ca.bytes_acked = net->mtu;
1224 net->htcp_ca.last_cong = sctp_get_tick_count();
1225}
1226
1227void
1228sctp_htcp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net)
1229{
1230 /*
1231 * We take the max of the burst limit times a MTU or the
1232 * INITIAL_CWND. We then limit this to 4 MTU's of sending.
1233 */
1234 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
1235 net->ssthresh = stcb->asoc.peers_rwnd;
1236 htcp_init(stcb, net);
1237
1238 if (SCTP_BASE_SYSCTL(sctp_logging_level) & (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) {
1239 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION);
1240 }
1241}
1242
1243void
1244sctp_htcp_cwnd_update_after_sack(struct sctp_tcb *stcb,
1245 struct sctp_association *asoc,
1246 int accum_moved, int reneged_all, int will_exit)
1247{
1248 struct sctp_nets *net;
1249
1250 /******************************/
1251 /* update cwnd and Early FR */
1252 /******************************/
1253 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
1254
1255#ifdef JANA_CMT_FAST_RECOVERY
1256 /*
1257 * CMT fast recovery code. Need to debug.
1258 */
1259 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
1260 if (compare_with_wrap(asoc->last_acked_seq,
1261 net->fast_recovery_tsn, MAX_TSN) ||
1262 (asoc->last_acked_seq == net->fast_recovery_tsn) ||
1263 compare_with_wrap(net->pseudo_cumack, net->fast_recovery_tsn, MAX_TSN) ||
1264 (net->pseudo_cumack == net->fast_recovery_tsn)) {
1265 net->will_exit_fast_recovery = 1;
1266 }
1267 }
1268#endif
1269 if (SCTP_BASE_SYSCTL(sctp_early_fr)) {
1270 /*
1271 * So, first of all do we need to have a Early FR
1272 * timer running?
1273 */
1274 if (((TAILQ_FIRST(&asoc->sent_queue)) &&
1275 (net->ref_count > 1) &&
1276 (net->flight_size < net->cwnd)) ||
1277 (reneged_all)) {
1278 /*
1279 * yes, so in this case stop it if its
1280 * running, and then restart it. Reneging
1281 * all is a special case where we want to
1282 * run the Early FR timer and then force the
1283 * last few unacked to be sent, causing us
1284 * to illicit a sack with gaps to force out
1285 * the others.
1286 */
1287 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
1288 SCTP_STAT_INCR(sctps_earlyfrstpidsck2);
1289 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
1290 SCTP_FROM_SCTP_INDATA + SCTP_LOC_20);
1291 }
1292 SCTP_STAT_INCR(sctps_earlyfrstrid);
1293 sctp_timer_start(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net);
1294 } else {
1295 /* No, stop it if its running */
1296 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
1297 SCTP_STAT_INCR(sctps_earlyfrstpidsck3);
1298 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
1299 SCTP_FROM_SCTP_INDATA + SCTP_LOC_21);
1300 }
1301 }
1302 }
1303 /* if nothing was acked on this destination skip it */
1304 if (net->net_ack == 0) {
1305 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1306 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
1307 }
1308 continue;
1309 }
1310 if (net->net_ack2 > 0) {
1311 /*
1312 * Karn's rule applies to clearing error count, this
1313 * is optional.
1314 */
1315 net->error_count = 0;
1316 if ((net->dest_state & SCTP_ADDR_NOT_REACHABLE) ==
1317 SCTP_ADDR_NOT_REACHABLE) {
1318 /* addr came good */
1319 net->dest_state &= ~SCTP_ADDR_NOT_REACHABLE;
1320 net->dest_state |= SCTP_ADDR_REACHABLE;
1321 sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
1322 SCTP_RECEIVED_SACK, (void *)net, SCTP_SO_NOT_LOCKED);
1323 /* now was it the primary? if so restore */
1324 if (net->dest_state & SCTP_ADDR_WAS_PRIMARY) {
1325 (void)sctp_set_primary_addr(stcb, (struct sockaddr *)NULL, net);
1326 }
1327 }
1328 /*
1329 * JRS 5/14/07 - If CMT PF is on and the destination
1330 * is in PF state, set the destination to active
1331 * state and set the cwnd to one or two MTU's based
1332 * on whether PF1 or PF2 is being used.
1333 *
1334 * Should we stop any running T3 timer here?
1335 */
1336 if (SCTP_BASE_SYSCTL(sctp_cmt_on_off) &&
1337 SCTP_BASE_SYSCTL(sctp_cmt_pf) &&
1338 ((net->dest_state & SCTP_ADDR_PF) == SCTP_ADDR_PF)) {
1339 net->dest_state &= ~SCTP_ADDR_PF;
1340 net->cwnd = net->mtu * SCTP_BASE_SYSCTL(sctp_cmt_pf);
1341 SCTPDBG(SCTP_DEBUG_INDATA1, "Destination %p moved from PF to reachable with cwnd %d.\n",
1342 net, net->cwnd);
1343 /*
1344 * Since the cwnd value is explicitly set,
1345 * skip the code that updates the cwnd
1346 * value.
1347 */
1348 goto skip_cwnd_update;
1349 }
1350 }
1351#ifdef JANA_CMT_FAST_RECOVERY
1352 /*
1353 * CMT fast recovery code
1354 */
1355 /*
1356 * if (sctp_cmt_on_off == 1 &&
1357 * net->fast_retran_loss_recovery &&
1358 * net->will_exit_fast_recovery == 0) { @@@ Do something }
1359 * else if (sctp_cmt_on_off == 0 &&
1360 * asoc->fast_retran_loss_recovery && will_exit == 0) {
1361 */
1362#endif
1363
1364 if (asoc->fast_retran_loss_recovery && will_exit == 0 && SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 0) {
1365 /*
1366 * If we are in loss recovery we skip any cwnd
1367 * update
1368 */
1369 goto skip_cwnd_update;
1370 }
1371 /*
1372 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
1373 * moved.
1374 */
1375 if (accum_moved || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) && net->new_pseudo_cumack)) {
1376 htcp_cong_avoid(stcb, net);
1377 measure_achieved_throughput(stcb, net);
1378 } else {
1379 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1380 sctp_log_cwnd(stcb, net, net->mtu,
1381 SCTP_CWND_LOG_NO_CUMACK);
1382 }
1383 }
1384skip_cwnd_update:
1385 /*
1386 * NOW, according to Karn's rule do we need to restore the
1387 * RTO timer back? Check our net_ack2. If not set then we
1388 * have a ambiguity.. i.e. all data ack'd was sent to more
1389 * than one place.
1390 */
1391 if (net->net_ack2) {
1392 /* restore any doubled timers */
1393 net->RTO = ((net->lastsa >> 2) + net->lastsv) >> 1;
1394 if (net->RTO < stcb->asoc.minrto) {
1395 net->RTO = stcb->asoc.minrto;
1396 }
1397 if (net->RTO > stcb->asoc.maxrto) {
1398 net->RTO = stcb->asoc.maxrto;
1399 }
1400 }
1401 }
1402}
1403
1404void
1405sctp_htcp_cwnd_update_after_fr(struct sctp_tcb *stcb,
1406 struct sctp_association *asoc)
1407{
1408 struct sctp_nets *net;
1409
1410 /*
1411 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off == 1) &&
1412 * (net->fast_retran_loss_recovery == 0)))
1413 */
1414 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
1415 if ((asoc->fast_retran_loss_recovery == 0) || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 1)) {
1416 /* out of a RFC2582 Fast recovery window? */
1417 if (net->net_ack > 0) {
1418 /*
1419 * per section 7.2.3, are there any
1420 * destinations that had a fast retransmit
1421 * to them. If so what we need to do is
1422 * adjust ssthresh and cwnd.
1423 */
1424 struct sctp_tmit_chunk *lchk;
1425 int old_cwnd = net->cwnd;
1426
1427 /* JRS - reset as if state were changed */
1428 htcp_reset(&net->htcp_ca);
1429 net->ssthresh = htcp_recalc_ssthresh(stcb, net);
1430 net->cwnd = net->ssthresh;
1431 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1432 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
1433 SCTP_CWND_LOG_FROM_FR);
1434 }
1435 lchk = TAILQ_FIRST(&asoc->send_queue);
1436
1437 net->partial_bytes_acked = 0;
1438 /* Turn on fast recovery window */
1439 asoc->fast_retran_loss_recovery = 1;
1440 if (lchk == NULL) {
1441 /* Mark end of the window */
1442 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
1443 } else {
1444 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
1445 }
1446
1447 /*
1448 * CMT fast recovery -- per destination
1449 * recovery variable.
1450 */
1451 net->fast_retran_loss_recovery = 1;
1452
1453 if (lchk == NULL) {
1454 /* Mark end of the window */
1455 net->fast_recovery_tsn = asoc->sending_seq - 1;
1456 } else {
1457 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
1458 }
1459
1460 /*
1461 * Disable Nonce Sum Checking and store the
1462 * resync tsn
1463 */
1464 asoc->nonce_sum_check = 0;
1465 asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
1466
1467 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
1468 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
1469 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
1470 stcb->sctp_ep, stcb, net);
1471 }
1472 } else if (net->net_ack > 0) {
1473 /*
1474 * Mark a peg that we WOULD have done a cwnd
1475 * reduction but RFC2582 prevented this action.
1476 */
1477 SCTP_STAT_INCR(sctps_fastretransinrtt);
1478 }
1479 }
1480}
1481
1482void
1483sctp_htcp_cwnd_update_after_timeout(struct sctp_tcb *stcb,
1484 struct sctp_nets *net)
1485{
1486 int old_cwnd = net->cwnd;
1487
1488 /* JRS - reset as if the state were being changed to timeout */
1489 htcp_reset(&net->htcp_ca);
1490 net->ssthresh = htcp_recalc_ssthresh(stcb, net);
1491 net->cwnd = net->mtu;
1492 net->partial_bytes_acked = 0;
1493 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1494 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX);
1495 }
1496}
1497
1498void
1499sctp_htcp_cwnd_update_after_fr_timer(struct sctp_inpcb *inp,
1500 struct sctp_tcb *stcb, struct sctp_nets *net)
1501{
1502 int old_cwnd;
1503
1504 old_cwnd = net->cwnd;
1505
1506 sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_EARLY_FR_TMR, SCTP_SO_NOT_LOCKED);
1507 net->htcp_ca.last_cong = sctp_get_tick_count();
1508 /*
1509 * make a small adjustment to cwnd and force to CA.
1510 */
1511 if (net->cwnd > net->mtu)
1512 /* drop down one MTU after sending */
1513 net->cwnd -= net->mtu;
1514 if (net->cwnd < net->ssthresh)
1515 /* still in SS move to CA */
1516 net->ssthresh = net->cwnd - 1;
1517 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1518 sctp_log_cwnd(stcb, net, (old_cwnd - net->cwnd), SCTP_CWND_LOG_FROM_FR);
1519 }
1520}
1521
1522void
1523sctp_htcp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb,
1524 struct sctp_nets *net)
1525{
1526 int old_cwnd;
1527
1528 old_cwnd = net->cwnd;
1529
1530 /* JRS - reset hctp as if state changed */
1531 htcp_reset(&net->htcp_ca);
1532 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
1533 net->ssthresh = htcp_recalc_ssthresh(stcb, net);
1534 if (net->ssthresh < net->mtu) {
1535 net->ssthresh = net->mtu;
1536 /* here back off the timer as well, to slow us down */
1537 net->RTO <<= 1;
1538 }
1539 net->cwnd = net->ssthresh;
1540 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1541 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
1542 }
1543}
2 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 *
7 * a) Redistributions of source code must retain the above copyright notice,
8 * this list of conditions and the following disclaimer.
9 *
10 * b) Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the distribution.
13 *
14 * c) Neither the name of Cisco Systems, Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived
16 * from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
20 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
28 * THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <netinet/sctp_os.h>
32#include <netinet/sctp_var.h>
33#include <netinet/sctp_sysctl.h>
34#include <netinet/sctp_pcb.h>
35#include <netinet/sctp_header.h>
36#include <netinet/sctputil.h>
37#include <netinet/sctp_output.h>
38#include <netinet/sctp_input.h>
39#include <netinet/sctp_indata.h>
40#include <netinet/sctp_uio.h>
41#include <netinet/sctp_timer.h>
42#include <netinet/sctp_auth.h>
43#include <netinet/sctp_asconf.h>
44#include <netinet/sctp_cc_functions.h>
45#include <sys/cdefs.h>
46__FBSDID("$FreeBSD: head/sys/netinet/sctp_cc_functions.c 179783 2008-06-14 07:58:05Z rrs $");
47void
48sctp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net)
49{
50 /*
51 * We take the max of the burst limit times a MTU or the
52 * INITIAL_CWND. We then limit this to 4 MTU's of sending. cwnd must
53 * be at least 2 MTU.
54 */
55 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
56 net->ssthresh = stcb->asoc.peers_rwnd;
57
58 if (SCTP_BASE_SYSCTL(sctp_logging_level) & (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) {
59 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION);
60 }
61}
62
63void
64sctp_cwnd_update_after_fr(struct sctp_tcb *stcb,
65 struct sctp_association *asoc)
66{
67 struct sctp_nets *net;
68
69 /*-
70 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off == 1) &&
71 * (net->fast_retran_loss_recovery == 0)))
72 */
73 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
74 if ((asoc->fast_retran_loss_recovery == 0) || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 1)) {
75 /* out of a RFC2582 Fast recovery window? */
76 if (net->net_ack > 0) {
77 /*
78 * per section 7.2.3, are there any
79 * destinations that had a fast retransmit
80 * to them. If so what we need to do is
81 * adjust ssthresh and cwnd.
82 */
83 struct sctp_tmit_chunk *lchk;
84 int old_cwnd = net->cwnd;
85
86 net->ssthresh = net->cwnd / 2;
87 if (net->ssthresh < (net->mtu * 2)) {
88 net->ssthresh = 2 * net->mtu;
89 }
90 net->cwnd = net->ssthresh;
91 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
92 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
93 SCTP_CWND_LOG_FROM_FR);
94 }
95 lchk = TAILQ_FIRST(&asoc->send_queue);
96
97 net->partial_bytes_acked = 0;
98 /* Turn on fast recovery window */
99 asoc->fast_retran_loss_recovery = 1;
100 if (lchk == NULL) {
101 /* Mark end of the window */
102 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
103 } else {
104 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
105 }
106
107 /*
108 * CMT fast recovery -- per destination
109 * recovery variable.
110 */
111 net->fast_retran_loss_recovery = 1;
112
113 if (lchk == NULL) {
114 /* Mark end of the window */
115 net->fast_recovery_tsn = asoc->sending_seq - 1;
116 } else {
117 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
118 }
119
120 /*
121 * Disable Nonce Sum Checking and store the
122 * resync tsn
123 */
124 asoc->nonce_sum_check = 0;
125 asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
126
127 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
128 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
129 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
130 stcb->sctp_ep, stcb, net);
131 }
132 } else if (net->net_ack > 0) {
133 /*
134 * Mark a peg that we WOULD have done a cwnd
135 * reduction but RFC2582 prevented this action.
136 */
137 SCTP_STAT_INCR(sctps_fastretransinrtt);
138 }
139 }
140}
141
142void
143sctp_cwnd_update_after_sack(struct sctp_tcb *stcb,
144 struct sctp_association *asoc,
145 int accum_moved, int reneged_all, int will_exit)
146{
147 struct sctp_nets *net;
148
149 /******************************/
150 /* update cwnd and Early FR */
151 /******************************/
152 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
153
154#ifdef JANA_CMT_FAST_RECOVERY
155 /*
156 * CMT fast recovery code. Need to debug.
157 */
158 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
159 if (compare_with_wrap(asoc->last_acked_seq,
160 net->fast_recovery_tsn, MAX_TSN) ||
161 (asoc->last_acked_seq == net->fast_recovery_tsn) ||
162 compare_with_wrap(net->pseudo_cumack, net->fast_recovery_tsn, MAX_TSN) ||
163 (net->pseudo_cumack == net->fast_recovery_tsn)) {
164 net->will_exit_fast_recovery = 1;
165 }
166 }
167#endif
168 if (SCTP_BASE_SYSCTL(sctp_early_fr)) {
169 /*
170 * So, first of all do we need to have a Early FR
171 * timer running?
172 */
173 if (((TAILQ_FIRST(&asoc->sent_queue)) &&
174 (net->ref_count > 1) &&
175 (net->flight_size < net->cwnd)) ||
176 (reneged_all)) {
177 /*
178 * yes, so in this case stop it if its
179 * running, and then restart it. Reneging
180 * all is a special case where we want to
181 * run the Early FR timer and then force the
182 * last few unacked to be sent, causing us
183 * to illicit a sack with gaps to force out
184 * the others.
185 */
186 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
187 SCTP_STAT_INCR(sctps_earlyfrstpidsck2);
188 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
189 SCTP_FROM_SCTP_INDATA + SCTP_LOC_20);
190 }
191 SCTP_STAT_INCR(sctps_earlyfrstrid);
192 sctp_timer_start(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net);
193 } else {
194 /* No, stop it if its running */
195 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
196 SCTP_STAT_INCR(sctps_earlyfrstpidsck3);
197 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
198 SCTP_FROM_SCTP_INDATA + SCTP_LOC_21);
199 }
200 }
201 }
202 /* if nothing was acked on this destination skip it */
203 if (net->net_ack == 0) {
204 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
205 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
206 }
207 continue;
208 }
209 if (net->net_ack2 > 0) {
210 /*
211 * Karn's rule applies to clearing error count, this
212 * is optional.
213 */
214 net->error_count = 0;
215 if ((net->dest_state & SCTP_ADDR_NOT_REACHABLE) ==
216 SCTP_ADDR_NOT_REACHABLE) {
217 /* addr came good */
218 net->dest_state &= ~SCTP_ADDR_NOT_REACHABLE;
219 net->dest_state |= SCTP_ADDR_REACHABLE;
220 sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
221 SCTP_RECEIVED_SACK, (void *)net, SCTP_SO_NOT_LOCKED);
222 /* now was it the primary? if so restore */
223 if (net->dest_state & SCTP_ADDR_WAS_PRIMARY) {
224 (void)sctp_set_primary_addr(stcb, (struct sockaddr *)NULL, net);
225 }
226 }
227 /*
228 * JRS 5/14/07 - If CMT PF is on and the destination
229 * is in PF state, set the destination to active
230 * state and set the cwnd to one or two MTU's based
231 * on whether PF1 or PF2 is being used.
232 *
233 * Should we stop any running T3 timer here?
234 */
235 if (SCTP_BASE_SYSCTL(sctp_cmt_on_off) &&
236 SCTP_BASE_SYSCTL(sctp_cmt_pf) &&
237 ((net->dest_state & SCTP_ADDR_PF) == SCTP_ADDR_PF)) {
238 net->dest_state &= ~SCTP_ADDR_PF;
239 net->cwnd = net->mtu * SCTP_BASE_SYSCTL(sctp_cmt_pf);
240 SCTPDBG(SCTP_DEBUG_INDATA1, "Destination %p moved from PF to reachable with cwnd %d.\n",
241 net, net->cwnd);
242 /*
243 * Since the cwnd value is explicitly set,
244 * skip the code that updates the cwnd
245 * value.
246 */
247 goto skip_cwnd_update;
248 }
249 }
250#ifdef JANA_CMT_FAST_RECOVERY
251 /*
252 * CMT fast recovery code
253 */
254 /*
255 * if (sctp_cmt_on_off == 1 &&
256 * net->fast_retran_loss_recovery &&
257 * net->will_exit_fast_recovery == 0) { @@@ Do something }
258 * else if (sctp_cmt_on_off == 0 &&
259 * asoc->fast_retran_loss_recovery && will_exit == 0) {
260 */
261#endif
262
263 if (asoc->fast_retran_loss_recovery && will_exit == 0 && SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 0) {
264 /*
265 * If we are in loss recovery we skip any cwnd
266 * update
267 */
268 goto skip_cwnd_update;
269 }
270 /*
271 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
272 * moved.
273 */
274 if (accum_moved || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) && net->new_pseudo_cumack)) {
275 /* If the cumulative ack moved we can proceed */
276 if (net->cwnd <= net->ssthresh) {
277 /* We are in slow start */
278 if (net->flight_size + net->net_ack >= net->cwnd) {
279 if (net->net_ack > (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable))) {
280 net->cwnd += (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable));
281 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
282 sctp_log_cwnd(stcb, net, net->mtu,
283 SCTP_CWND_LOG_FROM_SS);
284 }
285 } else {
286 net->cwnd += net->net_ack;
287 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
288 sctp_log_cwnd(stcb, net, net->net_ack,
289 SCTP_CWND_LOG_FROM_SS);
290 }
291 }
292 } else {
293 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
294 sctp_log_cwnd(stcb, net, net->net_ack,
295 SCTP_CWND_LOG_NOADV_SS);
296 }
297 }
298 } else {
299 /* We are in congestion avoidance */
300 /*
301 * Add to pba
302 */
303 net->partial_bytes_acked += net->net_ack;
304
305 if ((net->flight_size + net->net_ack >= net->cwnd) &&
306 (net->partial_bytes_acked >= net->cwnd)) {
307 net->partial_bytes_acked -= net->cwnd;
308 net->cwnd += net->mtu;
309 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
310 sctp_log_cwnd(stcb, net, net->mtu,
311 SCTP_CWND_LOG_FROM_CA);
312 }
313 } else {
314 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
315 sctp_log_cwnd(stcb, net, net->net_ack,
316 SCTP_CWND_LOG_NOADV_CA);
317 }
318 }
319 }
320 } else {
321 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
322 sctp_log_cwnd(stcb, net, net->mtu,
323 SCTP_CWND_LOG_NO_CUMACK);
324 }
325 }
326skip_cwnd_update:
327 /*
328 * NOW, according to Karn's rule do we need to restore the
329 * RTO timer back? Check our net_ack2. If not set then we
330 * have a ambiguity.. i.e. all data ack'd was sent to more
331 * than one place.
332 */
333 if (net->net_ack2) {
334 /* restore any doubled timers */
335 net->RTO = ((net->lastsa >> 2) + net->lastsv) >> 1;
336 if (net->RTO < stcb->asoc.minrto) {
337 net->RTO = stcb->asoc.minrto;
338 }
339 if (net->RTO > stcb->asoc.maxrto) {
340 net->RTO = stcb->asoc.maxrto;
341 }
342 }
343 }
344}
345
346void
347sctp_cwnd_update_after_timeout(struct sctp_tcb *stcb, struct sctp_nets *net)
348{
349 int old_cwnd = net->cwnd;
350
351 net->ssthresh = max(net->cwnd / 2, 2 * net->mtu);
352 net->cwnd = net->mtu;
353 net->partial_bytes_acked = 0;
354
355 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
356 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX);
357 }
358}
359
360void
361sctp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net)
362{
363 int old_cwnd = net->cwnd;
364
365 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
366 net->ssthresh = net->cwnd / 2;
367 if (net->ssthresh < net->mtu) {
368 net->ssthresh = net->mtu;
369 /* here back off the timer as well, to slow us down */
370 net->RTO <<= 1;
371 }
372 net->cwnd = net->ssthresh;
373 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
374 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
375 }
376}
377
378void
379sctp_cwnd_update_after_packet_dropped(struct sctp_tcb *stcb,
380 struct sctp_nets *net, struct sctp_pktdrop_chunk *cp,
381 uint32_t * bottle_bw, uint32_t * on_queue)
382{
383 uint32_t bw_avail;
384 int rtt, incr;
385 int old_cwnd = net->cwnd;
386
387 /* need real RTT for this calc */
388 rtt = ((net->lastsa >> 2) + net->lastsv) >> 1;
389 /* get bottle neck bw */
390 *bottle_bw = ntohl(cp->bottle_bw);
391 /* and whats on queue */
392 *on_queue = ntohl(cp->current_onq);
393 /*
394 * adjust the on-queue if our flight is more it could be that the
395 * router has not yet gotten data "in-flight" to it
396 */
397 if (*on_queue < net->flight_size)
398 *on_queue = net->flight_size;
399 /* calculate the available space */
400 bw_avail = (*bottle_bw * rtt) / 1000;
401 if (bw_avail > *bottle_bw) {
402 /*
403 * Cap the growth to no more than the bottle neck. This can
404 * happen as RTT slides up due to queues. It also means if
405 * you have more than a 1 second RTT with a empty queue you
406 * will be limited to the bottle_bw per second no matter if
407 * other points have 1/2 the RTT and you could get more
408 * out...
409 */
410 bw_avail = *bottle_bw;
411 }
412 if (*on_queue > bw_avail) {
413 /*
414 * No room for anything else don't allow anything else to be
415 * "added to the fire".
416 */
417 int seg_inflight, seg_onqueue, my_portion;
418
419 net->partial_bytes_acked = 0;
420
421 /* how much are we over queue size? */
422 incr = *on_queue - bw_avail;
423 if (stcb->asoc.seen_a_sack_this_pkt) {
424 /*
425 * undo any cwnd adjustment that the sack might have
426 * made
427 */
428 net->cwnd = net->prev_cwnd;
429 }
430 /* Now how much of that is mine? */
431 seg_inflight = net->flight_size / net->mtu;
432 seg_onqueue = *on_queue / net->mtu;
433 my_portion = (incr * seg_inflight) / seg_onqueue;
434
435 /* Have I made an adjustment already */
436 if (net->cwnd > net->flight_size) {
437 /*
438 * for this flight I made an adjustment we need to
439 * decrease the portion by a share our previous
440 * adjustment.
441 */
442 int diff_adj;
443
444 diff_adj = net->cwnd - net->flight_size;
445 if (diff_adj > my_portion)
446 my_portion = 0;
447 else
448 my_portion -= diff_adj;
449 }
450 /*
451 * back down to the previous cwnd (assume we have had a sack
452 * before this packet). minus what ever portion of the
453 * overage is my fault.
454 */
455 net->cwnd -= my_portion;
456
457 /* we will NOT back down more than 1 MTU */
458 if (net->cwnd <= net->mtu) {
459 net->cwnd = net->mtu;
460 }
461 /* force into CA */
462 net->ssthresh = net->cwnd - 1;
463 } else {
464 /*
465 * Take 1/4 of the space left or max burst up .. whichever
466 * is less.
467 */
468 incr = min((bw_avail - *on_queue) >> 2,
469 stcb->asoc.max_burst * net->mtu);
470 net->cwnd += incr;
471 }
472 if (net->cwnd > bw_avail) {
473 /* We can't exceed the pipe size */
474 net->cwnd = bw_avail;
475 }
476 if (net->cwnd < net->mtu) {
477 /* We always have 1 MTU */
478 net->cwnd = net->mtu;
479 }
480 if (net->cwnd - old_cwnd != 0) {
481 /* log only changes */
482 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
483 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
484 SCTP_CWND_LOG_FROM_SAT);
485 }
486 }
487}
488
489void
490sctp_cwnd_update_after_output(struct sctp_tcb *stcb,
491 struct sctp_nets *net, int burst_limit)
492{
493 int old_cwnd = net->cwnd;
494
495 if (net->ssthresh < net->cwnd)
496 net->ssthresh = net->cwnd;
497 net->cwnd = (net->flight_size + (burst_limit * net->mtu));
498
499 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
500 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_BRST);
501 }
502}
503
504void
505sctp_cwnd_update_after_fr_timer(struct sctp_inpcb *inp,
506 struct sctp_tcb *stcb, struct sctp_nets *net)
507{
508 int old_cwnd = net->cwnd;
509
510 sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_EARLY_FR_TMR, SCTP_SO_NOT_LOCKED);
511 /*
512 * make a small adjustment to cwnd and force to CA.
513 */
514 if (net->cwnd > net->mtu)
515 /* drop down one MTU after sending */
516 net->cwnd -= net->mtu;
517 if (net->cwnd < net->ssthresh)
518 /* still in SS move to CA */
519 net->ssthresh = net->cwnd - 1;
520 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
521 sctp_log_cwnd(stcb, net, (old_cwnd - net->cwnd), SCTP_CWND_LOG_FROM_FR);
522 }
523}
524
525struct sctp_hs_raise_drop {
526 int32_t cwnd;
527 int32_t increase;
528 int32_t drop_percent;
529};
530
531#define SCTP_HS_TABLE_SIZE 73
532
533struct sctp_hs_raise_drop sctp_cwnd_adjust[SCTP_HS_TABLE_SIZE] = {
534 {38, 1, 50}, /* 0 */
535 {118, 2, 44}, /* 1 */
536 {221, 3, 41}, /* 2 */
537 {347, 4, 38}, /* 3 */
538 {495, 5, 37}, /* 4 */
539 {663, 6, 35}, /* 5 */
540 {851, 7, 34}, /* 6 */
541 {1058, 8, 33}, /* 7 */
542 {1284, 9, 32}, /* 8 */
543 {1529, 10, 31}, /* 9 */
544 {1793, 11, 30}, /* 10 */
545 {2076, 12, 29}, /* 11 */
546 {2378, 13, 28}, /* 12 */
547 {2699, 14, 28}, /* 13 */
548 {3039, 15, 27}, /* 14 */
549 {3399, 16, 27}, /* 15 */
550 {3778, 17, 26}, /* 16 */
551 {4177, 18, 26}, /* 17 */
552 {4596, 19, 25}, /* 18 */
553 {5036, 20, 25}, /* 19 */
554 {5497, 21, 24}, /* 20 */
555 {5979, 22, 24}, /* 21 */
556 {6483, 23, 23}, /* 22 */
557 {7009, 24, 23}, /* 23 */
558 {7558, 25, 22}, /* 24 */
559 {8130, 26, 22}, /* 25 */
560 {8726, 27, 22}, /* 26 */
561 {9346, 28, 21}, /* 27 */
562 {9991, 29, 21}, /* 28 */
563 {10661, 30, 21}, /* 29 */
564 {11358, 31, 20}, /* 30 */
565 {12082, 32, 20}, /* 31 */
566 {12834, 33, 20}, /* 32 */
567 {13614, 34, 19}, /* 33 */
568 {14424, 35, 19}, /* 34 */
569 {15265, 36, 19}, /* 35 */
570 {16137, 37, 19}, /* 36 */
571 {17042, 38, 18}, /* 37 */
572 {17981, 39, 18}, /* 38 */
573 {18955, 40, 18}, /* 39 */
574 {19965, 41, 17}, /* 40 */
575 {21013, 42, 17}, /* 41 */
576 {22101, 43, 17}, /* 42 */
577 {23230, 44, 17}, /* 43 */
578 {24402, 45, 16}, /* 44 */
579 {25618, 46, 16}, /* 45 */
580 {26881, 47, 16}, /* 46 */
581 {28193, 48, 16}, /* 47 */
582 {29557, 49, 15}, /* 48 */
583 {30975, 50, 15}, /* 49 */
584 {32450, 51, 15}, /* 50 */
585 {33986, 52, 15}, /* 51 */
586 {35586, 53, 14}, /* 52 */
587 {37253, 54, 14}, /* 53 */
588 {38992, 55, 14}, /* 54 */
589 {40808, 56, 14}, /* 55 */
590 {42707, 57, 13}, /* 56 */
591 {44694, 58, 13}, /* 57 */
592 {46776, 59, 13}, /* 58 */
593 {48961, 60, 13}, /* 59 */
594 {51258, 61, 13}, /* 60 */
595 {53677, 62, 12}, /* 61 */
596 {56230, 63, 12}, /* 62 */
597 {58932, 64, 12}, /* 63 */
598 {61799, 65, 12}, /* 64 */
599 {64851, 66, 11}, /* 65 */
600 {68113, 67, 11}, /* 66 */
601 {71617, 68, 11}, /* 67 */
602 {75401, 69, 10}, /* 68 */
603 {79517, 70, 10}, /* 69 */
604 {84035, 71, 10}, /* 70 */
605 {89053, 72, 10}, /* 71 */
606 {94717, 73, 9} /* 72 */
607};
608
609static void
610sctp_hs_cwnd_increase(struct sctp_tcb *stcb, struct sctp_nets *net)
611{
612 int cur_val, i, indx, incr;
613
614 cur_val = net->cwnd >> 10;
615 indx = SCTP_HS_TABLE_SIZE - 1;
616#ifdef SCTP_DEBUG
617 printf("HS CC CAlled.\n");
618#endif
619 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
620 /* normal mode */
621 if (net->net_ack > net->mtu) {
622 net->cwnd += net->mtu;
623 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
624 sctp_log_cwnd(stcb, net, net->mtu, SCTP_CWND_LOG_FROM_SS);
625 }
626 } else {
627 net->cwnd += net->net_ack;
628 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
629 sctp_log_cwnd(stcb, net, net->net_ack, SCTP_CWND_LOG_FROM_SS);
630 }
631 }
632 } else {
633 for (i = net->last_hs_used; i < SCTP_HS_TABLE_SIZE; i++) {
634 if (cur_val < sctp_cwnd_adjust[i].cwnd) {
635 indx = i;
636 break;
637 }
638 }
639 net->last_hs_used = indx;
640 incr = ((sctp_cwnd_adjust[indx].increase) << 10);
641 net->cwnd += incr;
642 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
643 sctp_log_cwnd(stcb, net, incr, SCTP_CWND_LOG_FROM_SS);
644 }
645 }
646}
647
648static void
649sctp_hs_cwnd_decrease(struct sctp_tcb *stcb, struct sctp_nets *net)
650{
651 int cur_val, i, indx;
652 int old_cwnd = net->cwnd;
653
654 cur_val = net->cwnd >> 10;
655 indx = net->last_hs_used;
656 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
657 /* normal mode */
658 net->ssthresh = net->cwnd / 2;
659 if (net->ssthresh < (net->mtu * 2)) {
660 net->ssthresh = 2 * net->mtu;
661 }
662 net->cwnd = net->ssthresh;
663 } else {
664 /* drop by the proper amount */
665 net->ssthresh = net->cwnd - (int)((net->cwnd / 100) *
666 sctp_cwnd_adjust[net->last_hs_used].drop_percent);
667 net->cwnd = net->ssthresh;
668 /* now where are we */
669 indx = net->last_hs_used;
670 cur_val = net->cwnd >> 10;
671 /* reset where we are in the table */
672 if (cur_val < sctp_cwnd_adjust[0].cwnd) {
673 /* feel out of hs */
674 net->last_hs_used = 0;
675 } else {
676 for (i = indx; i >= 1; i--) {
677 if (cur_val > sctp_cwnd_adjust[i - 1].cwnd) {
678 break;
679 }
680 }
681 net->last_hs_used = indx;
682 }
683 }
684 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
685 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_FR);
686 }
687}
688
689void
690sctp_hs_cwnd_update_after_fr(struct sctp_tcb *stcb,
691 struct sctp_association *asoc)
692{
693 struct sctp_nets *net;
694
695 /*
696 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off == 1) &&
697 * (net->fast_retran_loss_recovery == 0)))
698 */
699 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
700 if ((asoc->fast_retran_loss_recovery == 0) || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 1)) {
701 /* out of a RFC2582 Fast recovery window? */
702 if (net->net_ack > 0) {
703 /*
704 * per section 7.2.3, are there any
705 * destinations that had a fast retransmit
706 * to them. If so what we need to do is
707 * adjust ssthresh and cwnd.
708 */
709 struct sctp_tmit_chunk *lchk;
710
711 sctp_hs_cwnd_decrease(stcb, net);
712
713 lchk = TAILQ_FIRST(&asoc->send_queue);
714
715 net->partial_bytes_acked = 0;
716 /* Turn on fast recovery window */
717 asoc->fast_retran_loss_recovery = 1;
718 if (lchk == NULL) {
719 /* Mark end of the window */
720 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
721 } else {
722 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
723 }
724
725 /*
726 * CMT fast recovery -- per destination
727 * recovery variable.
728 */
729 net->fast_retran_loss_recovery = 1;
730
731 if (lchk == NULL) {
732 /* Mark end of the window */
733 net->fast_recovery_tsn = asoc->sending_seq - 1;
734 } else {
735 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
736 }
737
738 /*
739 * Disable Nonce Sum Checking and store the
740 * resync tsn
741 */
742 asoc->nonce_sum_check = 0;
743 asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
744
745 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
746 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
747 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
748 stcb->sctp_ep, stcb, net);
749 }
750 } else if (net->net_ack > 0) {
751 /*
752 * Mark a peg that we WOULD have done a cwnd
753 * reduction but RFC2582 prevented this action.
754 */
755 SCTP_STAT_INCR(sctps_fastretransinrtt);
756 }
757 }
758}
759
760void
761sctp_hs_cwnd_update_after_sack(struct sctp_tcb *stcb,
762 struct sctp_association *asoc,
763 int accum_moved, int reneged_all, int will_exit)
764{
765 struct sctp_nets *net;
766
767 /******************************/
768 /* update cwnd and Early FR */
769 /******************************/
770 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
771
772#ifdef JANA_CMT_FAST_RECOVERY
773 /*
774 * CMT fast recovery code. Need to debug.
775 */
776 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
777 if (compare_with_wrap(asoc->last_acked_seq,
778 net->fast_recovery_tsn, MAX_TSN) ||
779 (asoc->last_acked_seq == net->fast_recovery_tsn) ||
780 compare_with_wrap(net->pseudo_cumack, net->fast_recovery_tsn, MAX_TSN) ||
781 (net->pseudo_cumack == net->fast_recovery_tsn)) {
782 net->will_exit_fast_recovery = 1;
783 }
784 }
785#endif
786 if (SCTP_BASE_SYSCTL(sctp_early_fr)) {
787 /*
788 * So, first of all do we need to have a Early FR
789 * timer running?
790 */
791 if (((TAILQ_FIRST(&asoc->sent_queue)) &&
792 (net->ref_count > 1) &&
793 (net->flight_size < net->cwnd)) ||
794 (reneged_all)) {
795 /*
796 * yes, so in this case stop it if its
797 * running, and then restart it. Reneging
798 * all is a special case where we want to
799 * run the Early FR timer and then force the
800 * last few unacked to be sent, causing us
801 * to illicit a sack with gaps to force out
802 * the others.
803 */
804 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
805 SCTP_STAT_INCR(sctps_earlyfrstpidsck2);
806 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
807 SCTP_FROM_SCTP_INDATA + SCTP_LOC_20);
808 }
809 SCTP_STAT_INCR(sctps_earlyfrstrid);
810 sctp_timer_start(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net);
811 } else {
812 /* No, stop it if its running */
813 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
814 SCTP_STAT_INCR(sctps_earlyfrstpidsck3);
815 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
816 SCTP_FROM_SCTP_INDATA + SCTP_LOC_21);
817 }
818 }
819 }
820 /* if nothing was acked on this destination skip it */
821 if (net->net_ack == 0) {
822 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
823 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
824 }
825 continue;
826 }
827 if (net->net_ack2 > 0) {
828 /*
829 * Karn's rule applies to clearing error count, this
830 * is optional.
831 */
832 net->error_count = 0;
833 if ((net->dest_state & SCTP_ADDR_NOT_REACHABLE) ==
834 SCTP_ADDR_NOT_REACHABLE) {
835 /* addr came good */
836 net->dest_state &= ~SCTP_ADDR_NOT_REACHABLE;
837 net->dest_state |= SCTP_ADDR_REACHABLE;
838 sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
839 SCTP_RECEIVED_SACK, (void *)net, SCTP_SO_NOT_LOCKED);
840 /* now was it the primary? if so restore */
841 if (net->dest_state & SCTP_ADDR_WAS_PRIMARY) {
842 (void)sctp_set_primary_addr(stcb, (struct sockaddr *)NULL, net);
843 }
844 }
845 /*
846 * JRS 5/14/07 - If CMT PF is on and the destination
847 * is in PF state, set the destination to active
848 * state and set the cwnd to one or two MTU's based
849 * on whether PF1 or PF2 is being used.
850 *
851 * Should we stop any running T3 timer here?
852 */
853 if (SCTP_BASE_SYSCTL(sctp_cmt_on_off) &&
854 SCTP_BASE_SYSCTL(sctp_cmt_pf) &&
855 ((net->dest_state & SCTP_ADDR_PF) == SCTP_ADDR_PF)) {
856 net->dest_state &= ~SCTP_ADDR_PF;
857 net->cwnd = net->mtu * SCTP_BASE_SYSCTL(sctp_cmt_pf);
858 SCTPDBG(SCTP_DEBUG_INDATA1, "Destination %p moved from PF to reachable with cwnd %d.\n",
859 net, net->cwnd);
860 /*
861 * Since the cwnd value is explicitly set,
862 * skip the code that updates the cwnd
863 * value.
864 */
865 goto skip_cwnd_update;
866 }
867 }
868#ifdef JANA_CMT_FAST_RECOVERY
869 /*
870 * CMT fast recovery code
871 */
872 /*
873 * if (sctp_cmt_on_off == 1 &&
874 * net->fast_retran_loss_recovery &&
875 * net->will_exit_fast_recovery == 0) { @@@ Do something }
876 * else if (sctp_cmt_on_off == 0 &&
877 * asoc->fast_retran_loss_recovery && will_exit == 0) {
878 */
879#endif
880
881 if (asoc->fast_retran_loss_recovery && will_exit == 0 && SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 0) {
882 /*
883 * If we are in loss recovery we skip any cwnd
884 * update
885 */
886 goto skip_cwnd_update;
887 }
888 /*
889 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
890 * moved.
891 */
892 if (accum_moved || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) && net->new_pseudo_cumack)) {
893 /* If the cumulative ack moved we can proceed */
894 if (net->cwnd <= net->ssthresh) {
895 /* We are in slow start */
896 if (net->flight_size + net->net_ack >= net->cwnd) {
897
898 sctp_hs_cwnd_increase(stcb, net);
899
900 } else {
901 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
902 sctp_log_cwnd(stcb, net, net->net_ack,
903 SCTP_CWND_LOG_NOADV_SS);
904 }
905 }
906 } else {
907 /* We are in congestion avoidance */
908 net->partial_bytes_acked += net->net_ack;
909 if ((net->flight_size + net->net_ack >= net->cwnd) &&
910 (net->partial_bytes_acked >= net->cwnd)) {
911 net->partial_bytes_acked -= net->cwnd;
912 net->cwnd += net->mtu;
913 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
914 sctp_log_cwnd(stcb, net, net->mtu,
915 SCTP_CWND_LOG_FROM_CA);
916 }
917 } else {
918 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
919 sctp_log_cwnd(stcb, net, net->net_ack,
920 SCTP_CWND_LOG_NOADV_CA);
921 }
922 }
923 }
924 } else {
925 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
926 sctp_log_cwnd(stcb, net, net->mtu,
927 SCTP_CWND_LOG_NO_CUMACK);
928 }
929 }
930skip_cwnd_update:
931 /*
932 * NOW, according to Karn's rule do we need to restore the
933 * RTO timer back? Check our net_ack2. If not set then we
934 * have a ambiguity.. i.e. all data ack'd was sent to more
935 * than one place.
936 */
937 if (net->net_ack2) {
938 /* restore any doubled timers */
939 net->RTO = ((net->lastsa >> 2) + net->lastsv) >> 1;
940 if (net->RTO < stcb->asoc.minrto) {
941 net->RTO = stcb->asoc.minrto;
942 }
943 if (net->RTO > stcb->asoc.maxrto) {
944 net->RTO = stcb->asoc.maxrto;
945 }
946 }
947 }
948}
949
950
951/*
952 * H-TCP congestion control. The algorithm is detailed in:
953 * R.N.Shorten, D.J.Leith:
954 * "H-TCP: TCP for high-speed and long-distance networks"
955 * Proc. PFLDnet, Argonne, 2004.
956 * http://www.hamilton.ie/net/htcp3.pdf
957 */
958
959
960static int use_rtt_scaling = 1;
961static int use_bandwidth_switch = 1;
962
963static inline int
964between(uint32_t seq1, uint32_t seq2, uint32_t seq3)
965{
966 return seq3 - seq2 >= seq1 - seq2;
967}
968
969static inline uint32_t
970htcp_cong_time(struct htcp *ca)
971{
972 return sctp_get_tick_count() - ca->last_cong;
973}
974
975static inline uint32_t
976htcp_ccount(struct htcp *ca)
977{
978 return htcp_cong_time(ca) / ca->minRTT;
979}
980
981static inline void
982htcp_reset(struct htcp *ca)
983{
984 ca->undo_last_cong = ca->last_cong;
985 ca->undo_maxRTT = ca->maxRTT;
986 ca->undo_old_maxB = ca->old_maxB;
987 ca->last_cong = sctp_get_tick_count();
988}
989
990#ifdef SCTP_NOT_USED
991
992static uint32_t
993htcp_cwnd_undo(struct sctp_tcb *stcb, struct sctp_nets *net)
994{
995 net->htcp_ca.last_cong = net->htcp_ca.undo_last_cong;
996 net->htcp_ca.maxRTT = net->htcp_ca.undo_maxRTT;
997 net->htcp_ca.old_maxB = net->htcp_ca.undo_old_maxB;
998 return max(net->cwnd, ((net->ssthresh / net->mtu << 7) / net->htcp_ca.beta) * net->mtu);
999}
1000
1001#endif
1002
1003static inline void
1004measure_rtt(struct sctp_tcb *stcb, struct sctp_nets *net)
1005{
1006 uint32_t srtt = net->lastsa >> 3;
1007
1008 /* keep track of minimum RTT seen so far, minRTT is zero at first */
1009 if (net->htcp_ca.minRTT > srtt || !net->htcp_ca.minRTT)
1010 net->htcp_ca.minRTT = srtt;
1011
1012 /* max RTT */
1013 if (net->fast_retran_ip == 0 && net->ssthresh < 0xFFFF && htcp_ccount(&net->htcp_ca) > 3) {
1014 if (net->htcp_ca.maxRTT < net->htcp_ca.minRTT)
1015 net->htcp_ca.maxRTT = net->htcp_ca.minRTT;
1016 if (net->htcp_ca.maxRTT < srtt && srtt <= net->htcp_ca.maxRTT + MSEC_TO_TICKS(20))
1017 net->htcp_ca.maxRTT = srtt;
1018 }
1019}
1020
1021static void
1022measure_achieved_throughput(struct sctp_tcb *stcb, struct sctp_nets *net)
1023{
1024 uint32_t now = sctp_get_tick_count();
1025
1026 if (net->fast_retran_ip == 0)
1027 net->htcp_ca.bytes_acked = net->net_ack;
1028
1029 if (!use_bandwidth_switch)
1030 return;
1031
1032 /* achieved throughput calculations */
1033 /* JRS - not 100% sure of this statement */
1034 if (net->fast_retran_ip == 1) {
1035 net->htcp_ca.bytecount = 0;
1036 net->htcp_ca.lasttime = now;
1037 return;
1038 }
1039 net->htcp_ca.bytecount += net->net_ack;
1040
1041 if (net->htcp_ca.bytecount >= net->cwnd - ((net->htcp_ca.alpha >> 7 ? : 1) * net->mtu)
1042 && now - net->htcp_ca.lasttime >= net->htcp_ca.minRTT
1043 && net->htcp_ca.minRTT > 0) {
1044 uint32_t cur_Bi = net->htcp_ca.bytecount / net->mtu * hz / (now - net->htcp_ca.lasttime);
1045
1046 if (htcp_ccount(&net->htcp_ca) <= 3) {
1047 /* just after backoff */
1048 net->htcp_ca.minB = net->htcp_ca.maxB = net->htcp_ca.Bi = cur_Bi;
1049 } else {
1050 net->htcp_ca.Bi = (3 * net->htcp_ca.Bi + cur_Bi) / 4;
1051 if (net->htcp_ca.Bi > net->htcp_ca.maxB)
1052 net->htcp_ca.maxB = net->htcp_ca.Bi;
1053 if (net->htcp_ca.minB > net->htcp_ca.maxB)
1054 net->htcp_ca.minB = net->htcp_ca.maxB;
1055 }
1056 net->htcp_ca.bytecount = 0;
1057 net->htcp_ca.lasttime = now;
1058 }
1059}
1060
1061static inline void
1062htcp_beta_update(struct htcp *ca, uint32_t minRTT, uint32_t maxRTT)
1063{
1064 if (use_bandwidth_switch) {
1065 uint32_t maxB = ca->maxB;
1066 uint32_t old_maxB = ca->old_maxB;
1067
1068 ca->old_maxB = ca->maxB;
1069
1070 if (!between(5 * maxB, 4 * old_maxB, 6 * old_maxB)) {
1071 ca->beta = BETA_MIN;
1072 ca->modeswitch = 0;
1073 return;
1074 }
1075 }
1076 if (ca->modeswitch && minRTT > (uint32_t) MSEC_TO_TICKS(10) && maxRTT) {
1077 ca->beta = (minRTT << 7) / maxRTT;
1078 if (ca->beta < BETA_MIN)
1079 ca->beta = BETA_MIN;
1080 else if (ca->beta > BETA_MAX)
1081 ca->beta = BETA_MAX;
1082 } else {
1083 ca->beta = BETA_MIN;
1084 ca->modeswitch = 1;
1085 }
1086}
1087
1088static inline void
1089htcp_alpha_update(struct htcp *ca)
1090{
1091 uint32_t minRTT = ca->minRTT;
1092 uint32_t factor = 1;
1093 uint32_t diff = htcp_cong_time(ca);
1094
1095 if (diff > (uint32_t) hz) {
1096 diff -= hz;
1097 factor = 1 + (10 * diff + ((diff / 2) * (diff / 2) / hz)) / hz;
1098 }
1099 if (use_rtt_scaling && minRTT) {
1100 uint32_t scale = (hz << 3) / (10 * minRTT);
1101
1102 scale = min(max(scale, 1U << 2), 10U << 3); /* clamping ratio to
1103 * interval [0.5,10]<<3 */
1104 factor = (factor << 3) / scale;
1105 if (!factor)
1106 factor = 1;
1107 }
1108 ca->alpha = 2 * factor * ((1 << 7) - ca->beta);
1109 if (!ca->alpha)
1110 ca->alpha = ALPHA_BASE;
1111}
1112
1113/* After we have the rtt data to calculate beta, we'd still prefer to wait one
1114 * rtt before we adjust our beta to ensure we are working from a consistent
1115 * data.
1116 *
1117 * This function should be called when we hit a congestion event since only at
1118 * that point do we really have a real sense of maxRTT (the queues en route
1119 * were getting just too full now).
1120 */
1121static void
1122htcp_param_update(struct sctp_tcb *stcb, struct sctp_nets *net)
1123{
1124 uint32_t minRTT = net->htcp_ca.minRTT;
1125 uint32_t maxRTT = net->htcp_ca.maxRTT;
1126
1127 htcp_beta_update(&net->htcp_ca, minRTT, maxRTT);
1128 htcp_alpha_update(&net->htcp_ca);
1129
1130 /*
1131 * add slowly fading memory for maxRTT to accommodate routing
1132 * changes etc
1133 */
1134 if (minRTT > 0 && maxRTT > minRTT)
1135 net->htcp_ca.maxRTT = minRTT + ((maxRTT - minRTT) * 95) / 100;
1136}
1137
1138static uint32_t
1139htcp_recalc_ssthresh(struct sctp_tcb *stcb, struct sctp_nets *net)
1140{
1141 htcp_param_update(stcb, net);
1142 return max(((net->cwnd / net->mtu * net->htcp_ca.beta) >> 7) * net->mtu, 2U * net->mtu);
1143}
1144
1145static void
1146htcp_cong_avoid(struct sctp_tcb *stcb, struct sctp_nets *net)
1147{
1148 /*-
1149 * How to handle these functions?
1150 * if (!tcp_is_cwnd_limited(sk, in_flight)) RRS - good question.
1151 * return;
1152 */
1153 if (net->cwnd <= net->ssthresh) {
1154 /* We are in slow start */
1155 if (net->flight_size + net->net_ack >= net->cwnd) {
1156 if (net->net_ack > (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable))) {
1157 net->cwnd += (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable));
1158 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1159 sctp_log_cwnd(stcb, net, net->mtu,
1160 SCTP_CWND_LOG_FROM_SS);
1161 }
1162 } else {
1163 net->cwnd += net->net_ack;
1164 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1165 sctp_log_cwnd(stcb, net, net->net_ack,
1166 SCTP_CWND_LOG_FROM_SS);
1167 }
1168 }
1169 } else {
1170 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1171 sctp_log_cwnd(stcb, net, net->net_ack,
1172 SCTP_CWND_LOG_NOADV_SS);
1173 }
1174 }
1175 } else {
1176 measure_rtt(stcb, net);
1177
1178 /*
1179 * In dangerous area, increase slowly. In theory this is
1180 * net->cwnd += alpha / net->cwnd
1181 */
1182 /* What is snd_cwnd_cnt?? */
1183 if (((net->partial_bytes_acked / net->mtu * net->htcp_ca.alpha) >> 7) * net->mtu >= net->cwnd) {
1184 /*-
1185 * Does SCTP have a cwnd clamp?
1186 * if (net->snd_cwnd < net->snd_cwnd_clamp) - Nope (RRS).
1187 */
1188 net->cwnd += net->mtu;
1189 net->partial_bytes_acked = 0;
1190 htcp_alpha_update(&net->htcp_ca);
1191 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1192 sctp_log_cwnd(stcb, net, net->mtu,
1193 SCTP_CWND_LOG_FROM_CA);
1194 }
1195 } else {
1196 net->partial_bytes_acked += net->net_ack;
1197 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1198 sctp_log_cwnd(stcb, net, net->net_ack,
1199 SCTP_CWND_LOG_NOADV_CA);
1200 }
1201 }
1202
1203 net->htcp_ca.bytes_acked = net->mtu;
1204 }
1205}
1206
1207#ifdef SCTP_NOT_USED
1208/* Lower bound on congestion window. */
1209static uint32_t
1210htcp_min_cwnd(struct sctp_tcb *stcb, struct sctp_nets *net)
1211{
1212 return net->ssthresh;
1213}
1214
1215#endif
1216
1217static void
1218htcp_init(struct sctp_tcb *stcb, struct sctp_nets *net)
1219{
1220 memset(&net->htcp_ca, 0, sizeof(struct htcp));
1221 net->htcp_ca.alpha = ALPHA_BASE;
1222 net->htcp_ca.beta = BETA_MIN;
1223 net->htcp_ca.bytes_acked = net->mtu;
1224 net->htcp_ca.last_cong = sctp_get_tick_count();
1225}
1226
1227void
1228sctp_htcp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net)
1229{
1230 /*
1231 * We take the max of the burst limit times a MTU or the
1232 * INITIAL_CWND. We then limit this to 4 MTU's of sending.
1233 */
1234 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND));
1235 net->ssthresh = stcb->asoc.peers_rwnd;
1236 htcp_init(stcb, net);
1237
1238 if (SCTP_BASE_SYSCTL(sctp_logging_level) & (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) {
1239 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION);
1240 }
1241}
1242
1243void
1244sctp_htcp_cwnd_update_after_sack(struct sctp_tcb *stcb,
1245 struct sctp_association *asoc,
1246 int accum_moved, int reneged_all, int will_exit)
1247{
1248 struct sctp_nets *net;
1249
1250 /******************************/
1251 /* update cwnd and Early FR */
1252 /******************************/
1253 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
1254
1255#ifdef JANA_CMT_FAST_RECOVERY
1256 /*
1257 * CMT fast recovery code. Need to debug.
1258 */
1259 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) {
1260 if (compare_with_wrap(asoc->last_acked_seq,
1261 net->fast_recovery_tsn, MAX_TSN) ||
1262 (asoc->last_acked_seq == net->fast_recovery_tsn) ||
1263 compare_with_wrap(net->pseudo_cumack, net->fast_recovery_tsn, MAX_TSN) ||
1264 (net->pseudo_cumack == net->fast_recovery_tsn)) {
1265 net->will_exit_fast_recovery = 1;
1266 }
1267 }
1268#endif
1269 if (SCTP_BASE_SYSCTL(sctp_early_fr)) {
1270 /*
1271 * So, first of all do we need to have a Early FR
1272 * timer running?
1273 */
1274 if (((TAILQ_FIRST(&asoc->sent_queue)) &&
1275 (net->ref_count > 1) &&
1276 (net->flight_size < net->cwnd)) ||
1277 (reneged_all)) {
1278 /*
1279 * yes, so in this case stop it if its
1280 * running, and then restart it. Reneging
1281 * all is a special case where we want to
1282 * run the Early FR timer and then force the
1283 * last few unacked to be sent, causing us
1284 * to illicit a sack with gaps to force out
1285 * the others.
1286 */
1287 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
1288 SCTP_STAT_INCR(sctps_earlyfrstpidsck2);
1289 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
1290 SCTP_FROM_SCTP_INDATA + SCTP_LOC_20);
1291 }
1292 SCTP_STAT_INCR(sctps_earlyfrstrid);
1293 sctp_timer_start(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net);
1294 } else {
1295 /* No, stop it if its running */
1296 if (SCTP_OS_TIMER_PENDING(&net->fr_timer.timer)) {
1297 SCTP_STAT_INCR(sctps_earlyfrstpidsck3);
1298 sctp_timer_stop(SCTP_TIMER_TYPE_EARLYFR, stcb->sctp_ep, stcb, net,
1299 SCTP_FROM_SCTP_INDATA + SCTP_LOC_21);
1300 }
1301 }
1302 }
1303 /* if nothing was acked on this destination skip it */
1304 if (net->net_ack == 0) {
1305 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1306 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK);
1307 }
1308 continue;
1309 }
1310 if (net->net_ack2 > 0) {
1311 /*
1312 * Karn's rule applies to clearing error count, this
1313 * is optional.
1314 */
1315 net->error_count = 0;
1316 if ((net->dest_state & SCTP_ADDR_NOT_REACHABLE) ==
1317 SCTP_ADDR_NOT_REACHABLE) {
1318 /* addr came good */
1319 net->dest_state &= ~SCTP_ADDR_NOT_REACHABLE;
1320 net->dest_state |= SCTP_ADDR_REACHABLE;
1321 sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
1322 SCTP_RECEIVED_SACK, (void *)net, SCTP_SO_NOT_LOCKED);
1323 /* now was it the primary? if so restore */
1324 if (net->dest_state & SCTP_ADDR_WAS_PRIMARY) {
1325 (void)sctp_set_primary_addr(stcb, (struct sockaddr *)NULL, net);
1326 }
1327 }
1328 /*
1329 * JRS 5/14/07 - If CMT PF is on and the destination
1330 * is in PF state, set the destination to active
1331 * state and set the cwnd to one or two MTU's based
1332 * on whether PF1 or PF2 is being used.
1333 *
1334 * Should we stop any running T3 timer here?
1335 */
1336 if (SCTP_BASE_SYSCTL(sctp_cmt_on_off) &&
1337 SCTP_BASE_SYSCTL(sctp_cmt_pf) &&
1338 ((net->dest_state & SCTP_ADDR_PF) == SCTP_ADDR_PF)) {
1339 net->dest_state &= ~SCTP_ADDR_PF;
1340 net->cwnd = net->mtu * SCTP_BASE_SYSCTL(sctp_cmt_pf);
1341 SCTPDBG(SCTP_DEBUG_INDATA1, "Destination %p moved from PF to reachable with cwnd %d.\n",
1342 net, net->cwnd);
1343 /*
1344 * Since the cwnd value is explicitly set,
1345 * skip the code that updates the cwnd
1346 * value.
1347 */
1348 goto skip_cwnd_update;
1349 }
1350 }
1351#ifdef JANA_CMT_FAST_RECOVERY
1352 /*
1353 * CMT fast recovery code
1354 */
1355 /*
1356 * if (sctp_cmt_on_off == 1 &&
1357 * net->fast_retran_loss_recovery &&
1358 * net->will_exit_fast_recovery == 0) { @@@ Do something }
1359 * else if (sctp_cmt_on_off == 0 &&
1360 * asoc->fast_retran_loss_recovery && will_exit == 0) {
1361 */
1362#endif
1363
1364 if (asoc->fast_retran_loss_recovery && will_exit == 0 && SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 0) {
1365 /*
1366 * If we are in loss recovery we skip any cwnd
1367 * update
1368 */
1369 goto skip_cwnd_update;
1370 }
1371 /*
1372 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has
1373 * moved.
1374 */
1375 if (accum_moved || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) && net->new_pseudo_cumack)) {
1376 htcp_cong_avoid(stcb, net);
1377 measure_achieved_throughput(stcb, net);
1378 } else {
1379 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
1380 sctp_log_cwnd(stcb, net, net->mtu,
1381 SCTP_CWND_LOG_NO_CUMACK);
1382 }
1383 }
1384skip_cwnd_update:
1385 /*
1386 * NOW, according to Karn's rule do we need to restore the
1387 * RTO timer back? Check our net_ack2. If not set then we
1388 * have a ambiguity.. i.e. all data ack'd was sent to more
1389 * than one place.
1390 */
1391 if (net->net_ack2) {
1392 /* restore any doubled timers */
1393 net->RTO = ((net->lastsa >> 2) + net->lastsv) >> 1;
1394 if (net->RTO < stcb->asoc.minrto) {
1395 net->RTO = stcb->asoc.minrto;
1396 }
1397 if (net->RTO > stcb->asoc.maxrto) {
1398 net->RTO = stcb->asoc.maxrto;
1399 }
1400 }
1401 }
1402}
1403
1404void
1405sctp_htcp_cwnd_update_after_fr(struct sctp_tcb *stcb,
1406 struct sctp_association *asoc)
1407{
1408 struct sctp_nets *net;
1409
1410 /*
1411 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off == 1) &&
1412 * (net->fast_retran_loss_recovery == 0)))
1413 */
1414 TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
1415 if ((asoc->fast_retran_loss_recovery == 0) || (SCTP_BASE_SYSCTL(sctp_cmt_on_off) == 1)) {
1416 /* out of a RFC2582 Fast recovery window? */
1417 if (net->net_ack > 0) {
1418 /*
1419 * per section 7.2.3, are there any
1420 * destinations that had a fast retransmit
1421 * to them. If so what we need to do is
1422 * adjust ssthresh and cwnd.
1423 */
1424 struct sctp_tmit_chunk *lchk;
1425 int old_cwnd = net->cwnd;
1426
1427 /* JRS - reset as if state were changed */
1428 htcp_reset(&net->htcp_ca);
1429 net->ssthresh = htcp_recalc_ssthresh(stcb, net);
1430 net->cwnd = net->ssthresh;
1431 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1432 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd),
1433 SCTP_CWND_LOG_FROM_FR);
1434 }
1435 lchk = TAILQ_FIRST(&asoc->send_queue);
1436
1437 net->partial_bytes_acked = 0;
1438 /* Turn on fast recovery window */
1439 asoc->fast_retran_loss_recovery = 1;
1440 if (lchk == NULL) {
1441 /* Mark end of the window */
1442 asoc->fast_recovery_tsn = asoc->sending_seq - 1;
1443 } else {
1444 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
1445 }
1446
1447 /*
1448 * CMT fast recovery -- per destination
1449 * recovery variable.
1450 */
1451 net->fast_retran_loss_recovery = 1;
1452
1453 if (lchk == NULL) {
1454 /* Mark end of the window */
1455 net->fast_recovery_tsn = asoc->sending_seq - 1;
1456 } else {
1457 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
1458 }
1459
1460 /*
1461 * Disable Nonce Sum Checking and store the
1462 * resync tsn
1463 */
1464 asoc->nonce_sum_check = 0;
1465 asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
1466
1467 sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
1468 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
1469 sctp_timer_start(SCTP_TIMER_TYPE_SEND,
1470 stcb->sctp_ep, stcb, net);
1471 }
1472 } else if (net->net_ack > 0) {
1473 /*
1474 * Mark a peg that we WOULD have done a cwnd
1475 * reduction but RFC2582 prevented this action.
1476 */
1477 SCTP_STAT_INCR(sctps_fastretransinrtt);
1478 }
1479 }
1480}
1481
1482void
1483sctp_htcp_cwnd_update_after_timeout(struct sctp_tcb *stcb,
1484 struct sctp_nets *net)
1485{
1486 int old_cwnd = net->cwnd;
1487
1488 /* JRS - reset as if the state were being changed to timeout */
1489 htcp_reset(&net->htcp_ca);
1490 net->ssthresh = htcp_recalc_ssthresh(stcb, net);
1491 net->cwnd = net->mtu;
1492 net->partial_bytes_acked = 0;
1493 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1494 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX);
1495 }
1496}
1497
1498void
1499sctp_htcp_cwnd_update_after_fr_timer(struct sctp_inpcb *inp,
1500 struct sctp_tcb *stcb, struct sctp_nets *net)
1501{
1502 int old_cwnd;
1503
1504 old_cwnd = net->cwnd;
1505
1506 sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_EARLY_FR_TMR, SCTP_SO_NOT_LOCKED);
1507 net->htcp_ca.last_cong = sctp_get_tick_count();
1508 /*
1509 * make a small adjustment to cwnd and force to CA.
1510 */
1511 if (net->cwnd > net->mtu)
1512 /* drop down one MTU after sending */
1513 net->cwnd -= net->mtu;
1514 if (net->cwnd < net->ssthresh)
1515 /* still in SS move to CA */
1516 net->ssthresh = net->cwnd - 1;
1517 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1518 sctp_log_cwnd(stcb, net, (old_cwnd - net->cwnd), SCTP_CWND_LOG_FROM_FR);
1519 }
1520}
1521
1522void
1523sctp_htcp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb,
1524 struct sctp_nets *net)
1525{
1526 int old_cwnd;
1527
1528 old_cwnd = net->cwnd;
1529
1530 /* JRS - reset hctp as if state changed */
1531 htcp_reset(&net->htcp_ca);
1532 SCTP_STAT_INCR(sctps_ecnereducedcwnd);
1533 net->ssthresh = htcp_recalc_ssthresh(stcb, net);
1534 if (net->ssthresh < net->mtu) {
1535 net->ssthresh = net->mtu;
1536 /* here back off the timer as well, to slow us down */
1537 net->RTO <<= 1;
1538 }
1539 net->cwnd = net->ssthresh;
1540 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
1541 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
1542 }
1543}