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