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sys/netinet/sctp_cc_functions.c
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1 /*- 2 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved. 3 * Copyright (c) 2008-2011, by Randall Stewart. All rights reserved. 4 * Copyright (c) 2008-2011, by Michael Tuexen. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * a) Redistributions of source code must retain the above copyright notice, 10 * this list of conditions and the following disclaimer. 11 * 12 * b) Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in 14 * the documentation and/or other materials provided with the distribution. 15 * 16 * c) Neither the name of Cisco Systems, Inc. nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 22 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 30 * THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <netinet/sctp_os.h> 34 #include <netinet/sctp_var.h> 35 #include <netinet/sctp_sysctl.h> 36 #include <netinet/sctp_pcb.h> 37 #include <netinet/sctp_header.h> 38 #include <netinet/sctputil.h> 39 #include <netinet/sctp_output.h> 40 #include <netinet/sctp_input.h> 41 #include <netinet/sctp_indata.h> 42 #include <netinet/sctp_uio.h> 43 #include <netinet/sctp_timer.h> 44 #include <netinet/sctp_auth.h> 45 #include <netinet/sctp_asconf.h> 46 #include <netinet/sctp_dtrace_declare.h> 47 #include <sys/cdefs.h> 48 __FBSDID("$FreeBSD: releng/9.0/sys/netinet/sctp_cc_functions.c 224641 2011-08-03 20:21:00Z tuexen $"); 49 50 #define SHIFT_MPTCP_MULTI_N 40 51 #define SHIFT_MPTCP_MULTI_Z 16 52 #define SHIFT_MPTCP_MULTI 8 53 54 static void 55 sctp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net) 56 { 57 struct sctp_association *assoc; 58 uint32_t cwnd_in_mtu; 59 60 assoc = &stcb->asoc; 61 cwnd_in_mtu = SCTP_BASE_SYSCTL(sctp_initial_cwnd); 62 if (cwnd_in_mtu == 0) { 63 /* Using 0 means that the value of RFC 4960 is used. */ 64 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND)); 65 } else { 66 /* 67 * We take the minimum of the burst limit and the initial 68 * congestion window. 69 */ 70 if ((assoc->max_burst > 0) && (cwnd_in_mtu > assoc->max_burst)) 71 cwnd_in_mtu = assoc->max_burst; 72 net->cwnd = (net->mtu - sizeof(struct sctphdr)) * cwnd_in_mtu; 73 } 74 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) || 75 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2)) { 76 /* In case of resource pooling initialize appropriately */ 77 net->cwnd /= assoc->numnets; 78 if (net->cwnd < (net->mtu - sizeof(struct sctphdr))) { 79 net->cwnd = net->mtu - sizeof(struct sctphdr); 80 } 81 } 82 net->ssthresh = assoc->peers_rwnd; 83 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); 342 343 if ((net->cc_mod.rtcc.steady_step) && (inst_ind != SCTP_INST_LOOSING)) { 344 if (net->cc_mod.rtcc.last_step_state == 5) 345 net->cc_mod.rtcc.step_cnt++; 346 else 347 net->cc_mod.rtcc.step_cnt = 1; 348 net->cc_mod.rtcc.last_step_state = 5; 349 if ((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) && 351 ((net->cc_mod.rtcc.step_cnt % net->cc_mod.rtcc.steady_step) == 0))) { 352 /* Try a step down */ 353 if (net->cwnd > (4 * net->mtu)) { 354 net->cwnd -= net->mtu; 355 net->cc_mod.rtcc.vol_reduce++; 356 return (1); 357 } else { 358 net->cc_mod.rtcc.step_cnt = 0; 359 } 360 } 361 } 362 if (inst_ind == SCTP_INST_GAINING) 363 return (1); 364 else if (inst_ind == SCTP_INST_NEUTRAL) 365 return (1); 366 else 367 return ((int)net->cc_mod.rtcc.ret_from_eq); 368 } 369 370 static int 371 cc_bw_decrease(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw, uint64_t rtt_offset, 372 uint64_t vtag, uint8_t inst_ind) 373 { 374 uint64_t oth, probepoint; 375 376 /* Bandwidth decreased. */ 377 probepoint = (((uint64_t) net->cwnd) << 32); 378 if (net->rtt > net->cc_mod.rtcc.lbw_rtt + rtt_offset) { 379 /* rtt increased */ 380 /* Did we add more */ 381 if ((net->cwnd > net->cc_mod.rtcc.cwnd_at_bw_set) && 382 (inst_ind != SCTP_INST_LOOSING)) { 383 /* We caused it maybe.. back off? */ 384 /* PROBE POINT 1 */ 385 probepoint |= ((1 << 16) | 1); 386 SDT_PROBE(sctp, cwnd, net, rttvar, 387 vtag, 388 ((net->cc_mod.rtcc.lbw << 32) | nbw), 389 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 390 net->flight_size, 391 probepoint); 392 393 if (net->cc_mod.rtcc.ret_from_eq) { 394 /* 395 * Switch over to CA if we are less 396 * aggressive 397 */ 398 net->ssthresh = net->cwnd - 1; 399 net->partial_bytes_acked = 0; 400 } 401 return (1); 402 } 403 /* Probe point 2 */ 404 probepoint |= ((2 << 16) | 0); 405 SDT_PROBE(sctp, cwnd, net, rttvar, 406 vtag, 407 ((net->cc_mod.rtcc.lbw << 32) | nbw), 408 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 409 net->flight_size, 410 probepoint); 411 412 /* Someone else - fight for more? */ 413 if (net->cc_mod.rtcc.steady_step) { 414 oth = net->cc_mod.rtcc.vol_reduce; 415 oth <<= 16; 416 oth |= net->cc_mod.rtcc.step_cnt; 417 oth <<= 16; 418 oth |= net->cc_mod.rtcc.last_step_state; 419 SDT_PROBE(sctp, cwnd, net, rttstep, 420 vtag, 421 ((net->cc_mod.rtcc.lbw << 32) | nbw), 422 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 423 oth, 424 probepoint); 425 /* 426 * Did we voluntarily give up some? if so take one 427 * back please 428 */ 429 if ((net->cc_mod.rtcc.vol_reduce) && 430 (inst_ind != SCTP_INST_GAINING)) { 431 net->cwnd += net->mtu; 432 net->cc_mod.rtcc.vol_reduce--; 433 } 434 net->cc_mod.rtcc.last_step_state = 2; 435 net->cc_mod.rtcc.step_cnt = 0; 436 } 437 goto out_decision; 438 } else if (net->rtt < net->cc_mod.rtcc.lbw_rtt - rtt_offset) { 439 /* bw & rtt decreased */ 440 /* Probe point 3 */ 441 probepoint |= ((3 << 16) | 0); 442 SDT_PROBE(sctp, cwnd, net, rttvar, 443 vtag, 444 ((net->cc_mod.rtcc.lbw << 32) | nbw), 445 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 446 net->flight_size, 447 probepoint); 448 if (net->cc_mod.rtcc.steady_step) { 449 oth = net->cc_mod.rtcc.vol_reduce; 450 oth <<= 16; 451 oth |= net->cc_mod.rtcc.step_cnt; 452 oth <<= 16; 453 oth |= net->cc_mod.rtcc.last_step_state; 454 SDT_PROBE(sctp, cwnd, net, rttstep, 455 vtag, 456 ((net->cc_mod.rtcc.lbw << 32) | nbw), 457 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 458 oth, 459 probepoint); 460 if ((net->cc_mod.rtcc.vol_reduce) && 461 (inst_ind != SCTP_INST_GAINING)) { 462 net->cwnd += net->mtu; 463 net->cc_mod.rtcc.vol_reduce--; 464 } 465 net->cc_mod.rtcc.last_step_state = 3; 466 net->cc_mod.rtcc.step_cnt = 0; 467 } 468 goto out_decision; 469 } 470 /* The bw decreased but rtt stayed the same */ 471 /* Probe point 4 */ 472 probepoint |= ((4 << 16) | 0); 473 SDT_PROBE(sctp, cwnd, net, rttvar, 474 vtag, 475 ((net->cc_mod.rtcc.lbw << 32) | nbw), 476 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 477 net->flight_size, 478 probepoint); 479 if (net->cc_mod.rtcc.steady_step) { 480 oth = net->cc_mod.rtcc.vol_reduce; 481 oth <<= 16; 482 oth |= net->cc_mod.rtcc.step_cnt; 483 oth <<= 16; 484 oth |= net->cc_mod.rtcc.last_step_state; 485 SDT_PROBE(sctp, cwnd, net, rttstep, 486 vtag, 487 ((net->cc_mod.rtcc.lbw << 32) | nbw), 488 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 489 oth, 490 probepoint); 491 if ((net->cc_mod.rtcc.vol_reduce) && 492 (inst_ind != SCTP_INST_GAINING)) { 493 net->cwnd += net->mtu; 494 net->cc_mod.rtcc.vol_reduce--; 495 } 496 net->cc_mod.rtcc.last_step_state = 4; 497 net->cc_mod.rtcc.step_cnt = 0; 498 } 499 out_decision: 500 net->cc_mod.rtcc.lbw = nbw; 501 net->cc_mod.rtcc.lbw_rtt = net->rtt; 502 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd; 503 if (inst_ind == SCTP_INST_GAINING) { 504 return (1); 505 } else { 506 return (0); 507 } 508 } 509 510 static int 511 cc_bw_increase(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw, 512 uint64_t vtag, uint8_t inst_ind) 513 { 514 uint64_t oth, probepoint; 515 516 /* 517 * BW increased, so update and return 0, since all actions in our 518 * table say to do the normal CC update. Note that we pay no 519 * attention to the inst_ind since our overall sum is increasing. 520 */ 521 /* PROBE POINT 0 */ 522 probepoint = (((uint64_t) net->cwnd) << 32); 523 SDT_PROBE(sctp, cwnd, net, rttvar, 524 vtag, 525 ((net->cc_mod.rtcc.lbw << 32) | nbw), 526 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 527 net->flight_size, 528 probepoint); 529 if (net->cc_mod.rtcc.steady_step) { 530 oth = net->cc_mod.rtcc.vol_reduce; 531 oth <<= 16; 532 oth |= net->cc_mod.rtcc.step_cnt; 533 oth <<= 16; 534 oth |= net->cc_mod.rtcc.last_step_state; 535 SDT_PROBE(sctp, cwnd, net, rttstep, 536 vtag, 537 ((net->cc_mod.rtcc.lbw << 32) | nbw), 538 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 539 oth, 540 probepoint); 541 net->cc_mod.rtcc.last_step_state = 0; 542 net->cc_mod.rtcc.step_cnt = 0; 543 net->cc_mod.rtcc.vol_reduce = 0; 544 } 545 net->cc_mod.rtcc.lbw = nbw; 546 net->cc_mod.rtcc.lbw_rtt = net->rtt; 547 net->cc_mod.rtcc.cwnd_at_bw_set = net->cwnd; 548 return (0); 549 } 550 551 /* RTCC Algoritm to limit growth of cwnd, return 552 * true if you want to NOT allow cwnd growth 553 */ 554 static int 555 cc_bw_limit(struct sctp_tcb *stcb, struct sctp_nets *net, uint64_t nbw) 556 { 557 uint64_t bw_offset, rtt_offset, rtt, vtag, probepoint; 558 uint64_t bytes_for_this_rtt, inst_bw; 559 uint64_t div, inst_off; 560 int bw_shift; 561 uint8_t inst_ind; 562 int ret; 563 564 /*- 565 * Here we need to see if we want 566 * to limit cwnd growth due to increase 567 * in overall rtt but no increase in bw. 568 * We use the following table to figure 569 * out what we should do. When we return 570 * 0, cc update goes on as planned. If we 571 * return 1, then no cc update happens and cwnd 572 * stays where it is at. 573 * ---------------------------------- 574 * BW | RTT | Action 575 * ********************************* 576 * INC | INC | return 0 577 * ---------------------------------- 578 * INC | SAME | return 0 579 * ---------------------------------- 580 * INC | DECR | return 0 581 * ---------------------------------- 582 * SAME | INC | return 1 583 * ---------------------------------- 584 * SAME | SAME | return 1 585 * ---------------------------------- 586 * SAME | DECR | return 0 587 * ---------------------------------- 588 * DECR | INC | return 0 or 1 based on if we caused. 589 * ---------------------------------- 590 * DECR | SAME | return 0 591 * ---------------------------------- 592 * DECR | DECR | return 0 593 * ---------------------------------- 594 * 595 * We are a bit fuzz on what an increase or 596 * decrease is. For BW it is the same if 597 * it did not change within 1/64th. For 598 * RTT it stayed the same if it did not 599 * change within 1/32nd 600 */ 601 bw_shift = SCTP_BASE_SYSCTL(sctp_rttvar_bw); 602 rtt = stcb->asoc.my_vtag; 603 vtag = (rtt << 32) | (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) | (stcb->rport); 604 probepoint = (((uint64_t) net->cwnd) << 32); 605 rtt = net->rtt; 606 if (net->cc_mod.rtcc.rtt_set_this_sack) { 607 net->cc_mod.rtcc.rtt_set_this_sack = 0; 608 bytes_for_this_rtt = net->cc_mod.rtcc.bw_bytes - net->cc_mod.rtcc.bw_bytes_at_last_rttc; 609 net->cc_mod.rtcc.bw_bytes_at_last_rttc = net->cc_mod.rtcc.bw_bytes; 610 if (net->rtt) { 611 div = net->rtt / 1000; 612 if (div) { 613 inst_bw = bytes_for_this_rtt / div; 614 inst_off = inst_bw >> bw_shift; 615 if (inst_bw > nbw) 616 inst_ind = SCTP_INST_GAINING; 617 else if ((inst_bw + inst_off) < nbw) 618 inst_ind = SCTP_INST_LOOSING; 619 else 620 inst_ind = SCTP_INST_NEUTRAL; 621 probepoint |= ((0xb << 16) | inst_ind); 622 } else { 623 inst_bw = bytes_for_this_rtt / (uint64_t) (net->rtt); 624 /* Can't determine do not change */ 625 inst_ind = net->cc_mod.rtcc.last_inst_ind; 626 probepoint |= ((0xc << 16) | inst_ind); 627 } 628 } else { 629 inst_bw = bytes_for_this_rtt; 630 /* Can't determine do not change */ 631 inst_ind = net->cc_mod.rtcc.last_inst_ind; 632 probepoint |= ((0xd << 16) | inst_ind); 633 } 634 SDT_PROBE(sctp, cwnd, net, rttvar, 635 vtag, 636 ((nbw << 32) | inst_bw), 637 ((net->cc_mod.rtcc.lbw_rtt << 32) | rtt), 638 net->flight_size, 639 probepoint); 640 } else { 641 /* No rtt measurement, use last one */ 642 inst_ind = net->cc_mod.rtcc.last_inst_ind; 643 } 644 bw_offset = net->cc_mod.rtcc.lbw >> bw_shift; 645 if (nbw > net->cc_mod.rtcc.lbw + bw_offset) { 646 ret = cc_bw_increase(stcb, net, nbw, vtag, inst_ind); 647 goto out; 648 } 649 rtt_offset = net->cc_mod.rtcc.lbw_rtt >> SCTP_BASE_SYSCTL(sctp_rttvar_rtt); 650 if (nbw < net->cc_mod.rtcc.lbw - bw_offset) { 651 ret = cc_bw_decrease(stcb, net, nbw, rtt_offset, vtag, inst_ind); 652 goto out; 653 } 654 /* 655 * If we reach here then we are in a situation where the bw stayed 656 * the same. 657 */ 658 ret = cc_bw_same(stcb, net, nbw, rtt_offset, vtag, inst_ind); 659 out: 660 net->cc_mod.rtcc.last_inst_ind = inst_ind; 661 return (ret); 662 } 663 664 static void 665 sctp_cwnd_update_after_sack_common(struct sctp_tcb *stcb, 666 struct sctp_association *asoc, 667 int accum_moved, int reneged_all, int will_exit, int use_rtcc) 668 { 669 struct sctp_nets *net; 670 int old_cwnd; 671 uint32_t t_ssthresh, t_cwnd, incr; 672 uint64_t t_ucwnd_sbw; 673 uint64_t t_path_mptcp; 674 uint64_t mptcp_like_alpha; 675 uint32_t srtt; 676 uint64_t max_path; 677 678 /* MT FIXME: Don't compute this over and over again */ 679 t_ssthresh = 0; 680 t_cwnd = 0; 681 t_ucwnd_sbw = 0; 682 t_path_mptcp = 0; 683 mptcp_like_alpha = 1; 684 if ((stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) || 685 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV2) || 686 (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_MPTCP)) { 687 max_path = 0; 688 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) { 689 t_ssthresh += net->ssthresh; 690 t_cwnd += net->cwnd; 691 /* lastsa>>3; we don't need to devide ... */ 692 srtt = net->lastsa; 693 if (srtt > 0) { 694 uint64_t tmp; 695 696 t_ucwnd_sbw += (uint64_t) net->cwnd / (uint64_t) srtt; 697 t_path_mptcp += (((uint64_t) net->cwnd) << SHIFT_MPTCP_MULTI_Z) / 698 (((uint64_t) net->mtu) * (uint64_t) srtt); 699 tmp = (((uint64_t) net->cwnd) << SHIFT_MPTCP_MULTI_N) / 700 ((uint64_t) net->mtu * (uint64_t) (srtt * srtt)); 701 if (tmp > max_path) { 702 max_path = tmp; 703 } 704 } 705 } 706 if (t_ucwnd_sbw == 0) { 707 t_ucwnd_sbw = 1; 708 } 709 if (t_path_mptcp > 0) { 710 mptcp_like_alpha = max_path / (t_path_mptcp * t_path_mptcp); 711 } else { 712 mptcp_like_alpha = 1; 713 } 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 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_ucwnd_sbw < 1) { 1017 t_ucwnd_sbw = 1; 1018 } 1019 if (stcb->asoc.sctp_cmt_on_off == SCTP_CMT_RPV1) { 1020 net->ssthresh = (uint32_t) (((uint64_t) 4 * 1021 (uint64_t) net->mtu * 1022 (uint64_t) net->ssthresh) / 1023 (uint64_t) t_ssthresh); 1024 } else { 1025 uint64_t cc_delta; 1026 1027 srtt = net->lastsa; 1028 /* lastsa>>3; we don't need to divide ... */ 1029 if (srtt == 0) { 1030 srtt = 1; 1031 } 1032 cc_delta = t_ucwnd_sbw * (uint64_t) srtt / 2; 1033 if (cc_delta < t_cwnd) { 1034 net->ssthresh = (uint32_t) ((uint64_t) t_cwnd - cc_delta); 1035 } else { 1036 net->ssthresh = net->mtu; 1037 } 1038 } 1039 if ((net->cwnd > t_cwnd / 2) && 1040 (net->ssthresh < net->cwnd - t_cwnd / 2)) { 1041 net->ssthresh = net->cwnd - t_cwnd / 2; 1042 } 1043 if (net->ssthresh < net->mtu) { 1044 net->ssthresh = net->mtu; 1045 } 1046 } else { 1047 net->ssthresh = max(net->cwnd / 2, 4 * net->mtu); 1048 } 1049 net->cwnd = net->mtu; 1050 net->partial_bytes_acked = 0; 1051 SDT_PROBE(sctp, cwnd, net, to, 1052 stcb->asoc.my_vtag, 1053 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 1054 net, 1055 old_cwnd, net->cwnd); 1056 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1057 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX); 1058 } 1059 } 1060 1061 static void 1062 sctp_cwnd_update_after_ecn_echo_common(struct sctp_tcb *stcb, struct sctp_nets *net, 1063 int in_window, int num_pkt_lost, int use_rtcc) 1064 { 1065 int old_cwnd = net->cwnd; 1066 1067 if ((use_rtcc) && (net->lan_type == SCTP_LAN_LOCAL) && (net->cc_mod.rtcc.use_dccc_ecn)) { 1068 /* Data center Congestion Control */ 1069 if (in_window == 0) { 1070 /* 1071 * Go to CA with the cwnd at the point we sent the 1072 * TSN that was marked with a CE. 1073 */ 1074 if (net->ecn_prev_cwnd < net->cwnd) { 1075 /* Restore to prev cwnd */ 1076 net->cwnd = net->ecn_prev_cwnd - (net->mtu * num_pkt_lost); 1077 } else { 1078 /* Just cut in 1/2 */ 1079 net->cwnd /= 2; 1080 } 1081 /* Drop to CA */ 1082 net->ssthresh = net->cwnd - (num_pkt_lost * net->mtu); 1083 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1084 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT); 1085 } 1086 } else { 1087 /* 1088 * Further tuning down required over the drastic 1089 * orginal cut 1090 */ 1091 net->ssthresh -= (net->mtu * num_pkt_lost); 1092 net->cwnd -= (net->mtu * num_pkt_lost); 1093 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1094 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT); 1095 } 1096 } 1097 SCTP_STAT_INCR(sctps_ecnereducedcwnd); 1098 } else { 1099 if (in_window == 0) { 1100 SCTP_STAT_INCR(sctps_ecnereducedcwnd); 1101 net->ssthresh = net->cwnd / 2; 1102 if (net->ssthresh < net->mtu) { 1103 net->ssthresh = net->mtu; 1104 /* 1105 * here back off the timer as well, to slow 1106 * us down 1107 */ 1108 net->RTO <<= 1; 1109 } 1110 net->cwnd = net->ssthresh; 1111 SDT_PROBE(sctp, cwnd, net, ecn, 1112 stcb->asoc.my_vtag, 1113 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 1114 net, 1115 old_cwnd, net->cwnd); 1116 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1117 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT); 1118 } 1119 } 1120 } 1121 1122 } 1123 1124 static void 1125 sctp_cwnd_update_after_packet_dropped(struct sctp_tcb *stcb, 1126 struct sctp_nets *net, struct sctp_pktdrop_chunk *cp, 1127 uint32_t * bottle_bw, uint32_t * on_queue) 1128 { 1129 uint32_t bw_avail; 1130 int rtt; 1131 unsigned int incr; 1132 int old_cwnd = net->cwnd; 1133 1134 /* need real RTT in msd for this calc */ 1135 rtt = net->rtt / 1000; 1136 /* get bottle neck bw */ 1137 *bottle_bw = ntohl(cp->bottle_bw); 1138 /* and whats on queue */ 1139 *on_queue = ntohl(cp->current_onq); 1140 /* 1141 * adjust the on-queue if our flight is more it could be that the 1142 * router has not yet gotten data "in-flight" to it 1143 */ 1144 if (*on_queue < net->flight_size) 1145 *on_queue = net->flight_size; 1146 /* calculate the available space */ 1147 bw_avail = (*bottle_bw * rtt) / 1000; 1148 if (bw_avail > *bottle_bw) { 1149 /* 1150 * Cap the growth to no more than the bottle neck. This can 1151 * happen as RTT slides up due to queues. It also means if 1152 * you have more than a 1 second RTT with a empty queue you 1153 * will be limited to the bottle_bw per second no matter if 1154 * other points have 1/2 the RTT and you could get more 1155 * out... 1156 */ 1157 bw_avail = *bottle_bw; 1158 } 1159 if (*on_queue > bw_avail) { 1160 /* 1161 * No room for anything else don't allow anything else to be 1162 * "added to the fire". 1163 */ 1164 int seg_inflight, seg_onqueue, my_portion; 1165 1166 net->partial_bytes_acked = 0; 1167 1168 /* how much are we over queue size? */ 1169 incr = *on_queue - bw_avail; 1170 if (stcb->asoc.seen_a_sack_this_pkt) { 1171 /* 1172 * undo any cwnd adjustment that the sack might have 1173 * made 1174 */ 1175 net->cwnd = net->prev_cwnd; 1176 } 1177 /* Now how much of that is mine? */ 1178 seg_inflight = net->flight_size / net->mtu; 1179 seg_onqueue = *on_queue / net->mtu; 1180 my_portion = (incr * seg_inflight) / seg_onqueue; 1181 1182 /* Have I made an adjustment already */ 1183 if (net->cwnd > net->flight_size) { 1184 /* 1185 * for this flight I made an adjustment we need to 1186 * decrease the portion by a share our previous 1187 * adjustment. 1188 */ 1189 int diff_adj; 1190 1191 diff_adj = net->cwnd - net->flight_size; 1192 if (diff_adj > my_portion) 1193 my_portion = 0; 1194 else 1195 my_portion -= diff_adj; 1196 } 1197 /* 1198 * back down to the previous cwnd (assume we have had a sack 1199 * before this packet). minus what ever portion of the 1200 * overage is my fault. 1201 */ 1202 net->cwnd -= my_portion; 1203 1204 /* we will NOT back down more than 1 MTU */ 1205 if (net->cwnd <= net->mtu) { 1206 net->cwnd = net->mtu; 1207 } 1208 /* force into CA */ 1209 net->ssthresh = net->cwnd - 1; 1210 } else { 1211 /* 1212 * Take 1/4 of the space left or max burst up .. whichever 1213 * is less. 1214 */ 1215 incr = (bw_avail - *on_queue) >> 2; 1216 if ((stcb->asoc.max_burst > 0) && 1217 (stcb->asoc.max_burst * net->mtu < incr)) { 1218 incr = stcb->asoc.max_burst * net->mtu; 1219 } 1220 net->cwnd += incr; 1221 } 1222 if (net->cwnd > bw_avail) { 1223 /* We can't exceed the pipe size */ 1224 net->cwnd = bw_avail; 1225 } 1226 if (net->cwnd < net->mtu) { 1227 /* We always have 1 MTU */ 1228 net->cwnd = net->mtu; 1229 } 1230 if (net->cwnd - old_cwnd != 0) { 1231 /* log only changes */ 1232 SDT_PROBE(sctp, cwnd, net, pd, 1233 stcb->asoc.my_vtag, 1234 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 1235 net, 1236 old_cwnd, net->cwnd); 1237 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1238 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), 1239 SCTP_CWND_LOG_FROM_SAT); 1240 } 1241 } 1242 } 1243 1244 static void 1245 sctp_cwnd_update_after_output(struct sctp_tcb *stcb, 1246 struct sctp_nets *net, int burst_limit) 1247 { 1248 int old_cwnd = net->cwnd; 1249 1250 if (net->ssthresh < net->cwnd) 1251 net->ssthresh = net->cwnd; 1252 if (burst_limit) { 1253 net->cwnd = (net->flight_size + (burst_limit * net->mtu)); 1254 SDT_PROBE(sctp, cwnd, net, bl, 1255 stcb->asoc.my_vtag, 1256 ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)), 1257 net, 1258 old_cwnd, net->cwnd); 1259 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1260 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_BRST); 1261 } 1262 } 1263 } 1264 1265 static void 1266 sctp_cwnd_update_after_sack(struct sctp_tcb *stcb, 1267 struct sctp_association *asoc, 1268 int accum_moved, int reneged_all, int will_exit) 1269 { 1270 /* Passing a zero argument in last disables the rtcc algoritm */ 1271 sctp_cwnd_update_after_sack_common(stcb, asoc, accum_moved, reneged_all, will_exit, 0); 1272 } 1273 1274 static void 1275 sctp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net, 1276 int in_window, int num_pkt_lost) 1277 { 1278 /* Passing a zero argument in last disables the rtcc algoritm */ 1279 sctp_cwnd_update_after_ecn_echo_common(stcb, net, in_window, num_pkt_lost, 0); 1280 } 1281 1282 /* Here starts the RTCCVAR type CC invented by RRS which 1283 * is a slight mod to RFC2581. We reuse a common routine or 1284 * two since these algoritms are so close and need to 1285 * remain the same. 1286 */ 1287 static void 1288 sctp_cwnd_update_rtcc_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net, 1289 int in_window, int num_pkt_lost) 1290 { 1291 sctp_cwnd_update_after_ecn_echo_common(stcb, net, in_window, num_pkt_lost, 1); 1292 } 1293 1294 1295 static 1296 void 1297 sctp_cwnd_update_rtcc_tsn_acknowledged(struct sctp_nets *net, 1298 struct sctp_tmit_chunk *tp1) 1299 { 1300 net->cc_mod.rtcc.bw_bytes += tp1->send_size; 1301 } 1302 1303 static void 1304 sctp_cwnd_prepare_rtcc_net_for_sack(struct sctp_tcb *stcb, 1305 struct sctp_nets *net) 1306 { 1307 if (net->cc_mod.rtcc.tls_needs_set > 0) { 1308 /* We had a bw measurment going on */ 1309 struct timeval ltls; 1310 1311 SCTP_GETPTIME_TIMEVAL(<ls); 1312 timevalsub(<ls, &net->cc_mod.rtcc.tls); 1313 net->cc_mod.rtcc.new_tot_time = (ltls.tv_sec * 1000000) + ltls.tv_usec; 1314 } 1315 } 1316 1317 static void 1318 sctp_cwnd_new_rtcc_transmission_begins(struct sctp_tcb *stcb, 1319 struct sctp_nets *net) 1320 { 1321 uint64_t vtag, probepoint; 1322 1323 if (net->cc_mod.rtcc.lbw) { 1324 /* Clear the old bw.. we went to 0 in-flight */ 1325 vtag = (net->rtt << 32) | (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) | 1326 (stcb->rport); 1327 probepoint = (((uint64_t) net->cwnd) << 32); 1328 /* Probe point 8 */ 1329 probepoint |= ((8 << 16) | 0); 1330 SDT_PROBE(sctp, cwnd, net, rttvar, 1331 vtag, 1332 ((net->cc_mod.rtcc.lbw << 32) | 0), 1333 ((net->cc_mod.rtcc.lbw_rtt << 32) | net->rtt), 1334 net->flight_size, 1335 probepoint); 1336 net->cc_mod.rtcc.lbw_rtt = 0; 1337 net->cc_mod.rtcc.cwnd_at_bw_set = 0; 1338 net->cc_mod.rtcc.lbw = 0; 1339 net->cc_mod.rtcc.bw_bytes_at_last_rttc = 0; 1340 net->cc_mod.rtcc.vol_reduce = 0; 1341 net->cc_mod.rtcc.bw_tot_time = 0; 1342 net->cc_mod.rtcc.bw_bytes = 0; 1343 net->cc_mod.rtcc.tls_needs_set = 0; 1344 if (net->cc_mod.rtcc.steady_step) { 1345 net->cc_mod.rtcc.vol_reduce = 0; 1346 net->cc_mod.rtcc.step_cnt = 0; 1347 net->cc_mod.rtcc.last_step_state = 0; 1348 } 1349 if (net->cc_mod.rtcc.ret_from_eq) { 1350 /* less aggressive one - reset cwnd too */ 1351 uint32_t cwnd_in_mtu, cwnd; 1352 1353 cwnd_in_mtu = SCTP_BASE_SYSCTL(sctp_initial_cwnd); 1354 if (cwnd_in_mtu == 0) { 1355 /* 1356 * Using 0 means that the value of RFC 4960 1357 * is used. 1358 */ 1359 cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND)); 1360 } else { 1361 /* 1362 * We take the minimum of the burst limit 1363 * and the initial congestion window. 1364 */ 1365 if ((stcb->asoc.max_burst > 0) && (cwnd_in_mtu > stcb->asoc.max_burst)) 1366 cwnd_in_mtu = stcb->asoc.max_burst; 1367 cwnd = (net->mtu - sizeof(struct sctphdr)) * cwnd_in_mtu; 1368 } 1369 if (net->cwnd > cwnd) { 1370 /* 1371 * Only set if we are not a timeout (i.e. 1372 * down to 1 mtu) 1373 */ 1374 net->cwnd = cwnd; 1375 } 1376 } 1377 } 1378 } 1379 1380 static void 1381 sctp_set_rtcc_initial_cc_param(struct sctp_tcb *stcb, 1382 struct sctp_nets *net) 1383 { 1384 uint64_t vtag, probepoint; 1385 1386 sctp_set_initial_cc_param(stcb, net); 1387 stcb->asoc.use_precise_time = 1; 1388 probepoint = (((uint64_t) net->cwnd) << 32); 1389 probepoint |= ((9 << 16) | 0); 1390 vtag = (net->rtt << 32) | 1391 (((uint32_t) (stcb->sctp_ep->sctp_lport)) << 16) | 1392 (stcb->rport); 1393 SDT_PROBE(sctp, cwnd, net, rttvar, 1394 vtag, 1395 0, 1396 0, 1397 0, 1398 probepoint); 1399 net->cc_mod.rtcc.lbw_rtt = 0; 1400 net->cc_mod.rtcc.cwnd_at_bw_set = 0; 1401 net->cc_mod.rtcc.vol_reduce = 0; 1402 net->cc_mod.rtcc.lbw = 0; 1403 net->cc_mod.rtcc.vol_reduce = 0; 1404 net->cc_mod.rtcc.bw_bytes_at_last_rttc = 0; 1405 net->cc_mod.rtcc.bw_tot_time = 0; 1406 net->cc_mod.rtcc.bw_bytes = 0; 1407 net->cc_mod.rtcc.tls_needs_set = 0; 1408 net->cc_mod.rtcc.ret_from_eq = SCTP_BASE_SYSCTL(sctp_rttvar_eqret); 1409 net->cc_mod.rtcc.steady_step = SCTP_BASE_SYSCTL(sctp_steady_step); 1410 net->cc_mod.rtcc.use_dccc_ecn = SCTP_BASE_SYSCTL(sctp_use_dccc_ecn); 1411 net->cc_mod.rtcc.step_cnt = 0; 1412 net->cc_mod.rtcc.last_step_state = 0; 1413 1414 1415 } 1416 1417 static int 1418 sctp_cwnd_rtcc_socket_option(struct sctp_tcb *stcb, int setorget, 1419 struct sctp_cc_option *cc_opt) 1420 { 1421 struct sctp_nets *net; 1422 1423 if (setorget == 1) { 1424 /* a set */ 1425 if (cc_opt->option == SCTP_CC_OPT_RTCC_SETMODE) { 1426 if ((cc_opt->aid_value.assoc_value != 0) && 1427 (cc_opt->aid_value.assoc_value != 1)) { 1428 return (EINVAL); 1429 } 1430 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) { 1431 net->cc_mod.rtcc.ret_from_eq = cc_opt->aid_value.assoc_value; 1432 } 1433 } else if (cc_opt->option == SCTP_CC_OPT_USE_DCCC_ECN) { 1434 if ((cc_opt->aid_value.assoc_value != 0) && 1435 (cc_opt->aid_value.assoc_value != 1)) { 1436 return (EINVAL); 1437 } 1438 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) { 1439 net->cc_mod.rtcc.use_dccc_ecn = cc_opt->aid_value.assoc_value; 1440 } 1441 } else if (cc_opt->option == SCTP_CC_OPT_STEADY_STEP) { 1442 TAILQ_FOREACH(net, &stcb->asoc.nets, sctp_next) { 1443 net->cc_mod.rtcc.steady_step = cc_opt->aid_value.assoc_value; 1444 } 1445 } else { 1446 return (EINVAL); 1447 } 1448 } else { 1449 /* a get */ 1450 if (cc_opt->option == SCTP_CC_OPT_RTCC_SETMODE) { 1451 net = TAILQ_FIRST(&stcb->asoc.nets); 1452 if (net == NULL) { 1453 return (EFAULT); 1454 } 1455 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.ret_from_eq; 1456 } else if (cc_opt->option == SCTP_CC_OPT_USE_DCCC_ECN) { 1457 net = TAILQ_FIRST(&stcb->asoc.nets); 1458 if (net == NULL) { 1459 return (EFAULT); 1460 } 1461 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.use_dccc_ecn; 1462 } else if (cc_opt->option == SCTP_CC_OPT_STEADY_STEP) { 1463 net = TAILQ_FIRST(&stcb->asoc.nets); 1464 if (net == NULL) { 1465 return (EFAULT); 1466 } 1467 cc_opt->aid_value.assoc_value = net->cc_mod.rtcc.steady_step; 1468 } else { 1469 return (EINVAL); 1470 } 1471 } 1472 return (0); 1473 } 1474 1475 static void 1476 sctp_cwnd_update_rtcc_packet_transmitted(struct sctp_tcb *stcb, 1477 struct sctp_nets *net) 1478 { 1479 if (net->cc_mod.rtcc.tls_needs_set == 0) { 1480 SCTP_GETPTIME_TIMEVAL(&net->cc_mod.rtcc.tls); 1481 net->cc_mod.rtcc.tls_needs_set = 2; 1482 } 1483 } 1484 1485 static void 1486 sctp_cwnd_update_rtcc_after_sack(struct sctp_tcb *stcb, 1487 struct sctp_association *asoc, 1488 int accum_moved, int reneged_all, int will_exit) 1489 { 1490 /* Passing a one argument at the last enables the rtcc algoritm */ 1491 sctp_cwnd_update_after_sack_common(stcb, asoc, accum_moved, reneged_all, will_exit, 1); 1492 } 1493 1494 static void 1495 sctp_rtt_rtcc_calculated(struct sctp_tcb *stcb, 1496 struct sctp_nets *net, struct timeval *now) 1497 { 1498 net->cc_mod.rtcc.rtt_set_this_sack = 1; 1499 } 1500 1501 /* Here starts Sally Floyds HS-TCP */ 1502 1503 struct sctp_hs_raise_drop { 1504 int32_t cwnd; 1505 int32_t increase; 1506 int32_t drop_percent; 1507 }; 1508 1509 #define SCTP_HS_TABLE_SIZE 73 1510 1511 struct sctp_hs_raise_drop sctp_cwnd_adjust[SCTP_HS_TABLE_SIZE] = { 1512 {38, 1, 50}, /* 0 */ 1513 {118, 2, 44}, /* 1 */ 1514 {221, 3, 41}, /* 2 */ 1515 {347, 4, 38}, /* 3 */ 1516 {495, 5, 37}, /* 4 */ 1517 {663, 6, 35}, /* 5 */ 1518 {851, 7, 34}, /* 6 */ 1519 {1058, 8, 33}, /* 7 */ 1520 {1284, 9, 32}, /* 8 */ 1521 {1529, 10, 31}, /* 9 */ 1522 {1793, 11, 30}, /* 10 */ 1523 {2076, 12, 29}, /* 11 */ 1524 {2378, 13, 28}, /* 12 */ 1525 {2699, 14, 28}, /* 13 */ 1526 {3039, 15, 27}, /* 14 */ 1527 {3399, 16, 27}, /* 15 */ 1528 {3778, 17, 26}, /* 16 */ 1529 {4177, 18, 26}, /* 17 */ 1530 {4596, 19, 25}, /* 18 */ 1531 {5036, 20, 25}, /* 19 */ 1532 {5497, 21, 24}, /* 20 */ 1533 {5979, 22, 24}, /* 21 */ 1534 {6483, 23, 23}, /* 22 */ 1535 {7009, 24, 23}, /* 23 */ 1536 {7558, 25, 22}, /* 24 */ 1537 {8130, 26, 22}, /* 25 */ 1538 {8726, 27, 22}, /* 26 */ 1539 {9346, 28, 21}, /* 27 */ 1540 {9991, 29, 21}, /* 28 */ 1541 {10661, 30, 21}, /* 29 */ 1542 {11358, 31, 20}, /* 30 */ 1543 {12082, 32, 20}, /* 31 */ 1544 {12834, 33, 20}, /* 32 */ 1545 {13614, 34, 19}, /* 33 */ 1546 {14424, 35, 19}, /* 34 */ 1547 {15265, 36, 19}, /* 35 */ 1548 {16137, 37, 19}, /* 36 */ 1549 {17042, 38, 18}, /* 37 */ 1550 {17981, 39, 18}, /* 38 */ 1551 {18955, 40, 18}, /* 39 */ 1552 {19965, 41, 17}, /* 40 */ 1553 {21013, 42, 17}, /* 41 */ 1554 {22101, 43, 17}, /* 42 */ 1555 {23230, 44, 17}, /* 43 */ 1556 {24402, 45, 16}, /* 44 */ 1557 {25618, 46, 16}, /* 45 */ 1558 {26881, 47, 16}, /* 46 */ 1559 {28193, 48, 16}, /* 47 */ 1560 {29557, 49, 15}, /* 48 */ 1561 {30975, 50, 15}, /* 49 */ 1562 {32450, 51, 15}, /* 50 */ 1563 {33986, 52, 15}, /* 51 */ 1564 {35586, 53, 14}, /* 52 */ 1565 {37253, 54, 14}, /* 53 */ 1566 {38992, 55, 14}, /* 54 */ 1567 {40808, 56, 14}, /* 55 */ 1568 {42707, 57, 13}, /* 56 */ 1569 {44694, 58, 13}, /* 57 */ 1570 {46776, 59, 13}, /* 58 */ 1571 {48961, 60, 13}, /* 59 */ 1572 {51258, 61, 13}, /* 60 */ 1573 {53677, 62, 12}, /* 61 */ 1574 {56230, 63, 12}, /* 62 */ 1575 {58932, 64, 12}, /* 63 */ 1576 {61799, 65, 12}, /* 64 */ 1577 {64851, 66, 11}, /* 65 */ 1578 {68113, 67, 11}, /* 66 */ 1579 {71617, 68, 11}, /* 67 */ 1580 {75401, 69, 10}, /* 68 */ 1581 {79517, 70, 10}, /* 69 */ 1582 {84035, 71, 10}, /* 70 */ 1583 {89053, 72, 10}, /* 71 */ 1584 {94717, 73, 9} /* 72 */ 1585 }; 1586 1587 static void 1588 sctp_hs_cwnd_increase(struct sctp_tcb *stcb, struct sctp_nets *net) 1589 { 1590 int cur_val, i, indx, incr; 1591 1592 cur_val = net->cwnd >> 10; 1593 indx = SCTP_HS_TABLE_SIZE - 1; 1594 #ifdef SCTP_DEBUG 1595 printf("HS CC CAlled.\n"); 1596 #endif 1597 if (cur_val < sctp_cwnd_adjust[0].cwnd) { 1598 /* normal mode */ 1599 if (net->net_ack > net->mtu) { 1600 net->cwnd += net->mtu; 1601 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1602 sctp_log_cwnd(stcb, net, net->mtu, SCTP_CWND_LOG_FROM_SS); 1603 } 1604 } else { 1605 net->cwnd += net->net_ack; 1606 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1607 sctp_log_cwnd(stcb, net, net->net_ack, SCTP_CWND_LOG_FROM_SS); 1608 } 1609 } 1610 } else { 1611 for (i = net->last_hs_used; i < SCTP_HS_TABLE_SIZE; i++) { 1612 if (cur_val < sctp_cwnd_adjust[i].cwnd) { 1613 indx = i; 1614 break; 1615 } 1616 } 1617 net->last_hs_used = indx; 1618 incr = ((sctp_cwnd_adjust[indx].increase) << 10); 1619 net->cwnd += incr; 1620 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1621 sctp_log_cwnd(stcb, net, incr, SCTP_CWND_LOG_FROM_SS); 1622 } 1623 } 1624 } 1625 1626 static void 1627 sctp_hs_cwnd_decrease(struct sctp_tcb *stcb, struct sctp_nets *net) 1628 { 1629 int cur_val, i, indx; 1630 int old_cwnd = net->cwnd; 1631 1632 cur_val = net->cwnd >> 10; 1633 if (cur_val < sctp_cwnd_adjust[0].cwnd) { 1634 /* normal mode */ 1635 net->ssthresh = net->cwnd / 2; 1636 if (net->ssthresh < (net->mtu * 2)) { 1637 net->ssthresh = 2 * net->mtu; 1638 } 1639 net->cwnd = net->ssthresh; 1640 } else { 1641 /* drop by the proper amount */ 1642 net->ssthresh = net->cwnd - (int)((net->cwnd / 100) * 1643 sctp_cwnd_adjust[net->last_hs_used].drop_percent); 1644 net->cwnd = net->ssthresh; 1645 /* now where are we */ 1646 indx = net->last_hs_used; 1647 cur_val = net->cwnd >> 10; 1648 /* reset where we are in the table */ 1649 if (cur_val < sctp_cwnd_adjust[0].cwnd) { 1650 /* feel out of hs */ 1651 net->last_hs_used = 0; 1652 } else { 1653 for (i = indx; i >= 1; i--) { 1654 if (cur_val > sctp_cwnd_adjust[i - 1].cwnd) { 1655 break; 1656 } 1657 } 1658 net->last_hs_used = indx; 1659 } 1660 } 1661 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1662 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_FR); 1663 } 1664 } 1665 1666 static void 1667 sctp_hs_cwnd_update_after_fr(struct sctp_tcb *stcb, 1668 struct sctp_association *asoc) 1669 { 1670 struct sctp_nets *net; 1671 1672 /* 1673 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) && 1674 * (net->fast_retran_loss_recovery == 0))) 1675 */ 1676 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 1677 if ((asoc->fast_retran_loss_recovery == 0) || 1678 (asoc->sctp_cmt_on_off > 0)) { 1679 /* out of a RFC2582 Fast recovery window? */ 1680 if (net->net_ack > 0) { 1681 /* 1682 * per section 7.2.3, are there any 1683 * destinations that had a fast retransmit 1684 * to them. If so what we need to do is 1685 * adjust ssthresh and cwnd. 1686 */ 1687 struct sctp_tmit_chunk *lchk; 1688 1689 sctp_hs_cwnd_decrease(stcb, net); 1690 1691 lchk = TAILQ_FIRST(&asoc->send_queue); 1692 1693 net->partial_bytes_acked = 0; 1694 /* Turn on fast recovery window */ 1695 asoc->fast_retran_loss_recovery = 1; 1696 if (lchk == NULL) { 1697 /* Mark end of the window */ 1698 asoc->fast_recovery_tsn = asoc->sending_seq - 1; 1699 } else { 1700 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 1701 } 1702 1703 /* 1704 * CMT fast recovery -- per destination 1705 * recovery variable. 1706 */ 1707 net->fast_retran_loss_recovery = 1; 1708 1709 if (lchk == NULL) { 1710 /* Mark end of the window */ 1711 net->fast_recovery_tsn = asoc->sending_seq - 1; 1712 } else { 1713 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 1714 } 1715 1716 sctp_timer_stop(SCTP_TIMER_TYPE_SEND, 1717 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32); 1718 sctp_timer_start(SCTP_TIMER_TYPE_SEND, 1719 stcb->sctp_ep, stcb, net); 1720 } 1721 } else if (net->net_ack > 0) { 1722 /* 1723 * Mark a peg that we WOULD have done a cwnd 1724 * reduction but RFC2582 prevented this action. 1725 */ 1726 SCTP_STAT_INCR(sctps_fastretransinrtt); 1727 } 1728 } 1729 } 1730 1731 static void 1732 sctp_hs_cwnd_update_after_sack(struct sctp_tcb *stcb, 1733 struct sctp_association *asoc, 1734 int accum_moved, int reneged_all, int will_exit) 1735 { 1736 struct sctp_nets *net; 1737 1738 /******************************/ 1739 /* update cwnd and Early FR */ 1740 /******************************/ 1741 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 1742 1743 #ifdef JANA_CMT_FAST_RECOVERY 1744 /* 1745 * CMT fast recovery code. Need to debug. 1746 */ 1747 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) { 1748 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) || 1749 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) { 1750 net->will_exit_fast_recovery = 1; 1751 } 1752 } 1753 #endif 1754 /* if nothing was acked on this destination skip it */ 1755 if (net->net_ack == 0) { 1756 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 1757 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK); 1758 } 1759 continue; 1760 } 1761 #ifdef JANA_CMT_FAST_RECOVERY 1762 /* 1763 * CMT fast recovery code 1764 */ 1765 /* 1766 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery 1767 * && net->will_exit_fast_recovery == 0) { @@@ Do something 1768 * } else if (sctp_cmt_on_off == 0 && 1769 * asoc->fast_retran_loss_recovery && will_exit == 0) { 1770 */ 1771 #endif 1772 1773 if (asoc->fast_retran_loss_recovery && 1774 (will_exit == 0) && 1775 (asoc->sctp_cmt_on_off == 0)) { 1776 /* 1777 * If we are in loss recovery we skip any cwnd 1778 * update 1779 */ 1780 return; 1781 } 1782 /* 1783 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has 1784 * moved. 1785 */ 1786 if (accum_moved || 1787 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) { 1788 /* If the cumulative ack moved we can proceed */ 1789 if (net->cwnd <= net->ssthresh) { 1790 /* We are in slow start */ 1791 if (net->flight_size + net->net_ack >= net->cwnd) { 1792 1793 sctp_hs_cwnd_increase(stcb, net); 1794 1795 } else { 1796 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 1797 sctp_log_cwnd(stcb, net, net->net_ack, 1798 SCTP_CWND_LOG_NOADV_SS); 1799 } 1800 } 1801 } else { 1802 /* We are in congestion avoidance */ 1803 net->partial_bytes_acked += net->net_ack; 1804 if ((net->flight_size + net->net_ack >= net->cwnd) && 1805 (net->partial_bytes_acked >= net->cwnd)) { 1806 net->partial_bytes_acked -= net->cwnd; 1807 net->cwnd += net->mtu; 1808 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 1809 sctp_log_cwnd(stcb, net, net->mtu, 1810 SCTP_CWND_LOG_FROM_CA); 1811 } 1812 } else { 1813 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 1814 sctp_log_cwnd(stcb, net, net->net_ack, 1815 SCTP_CWND_LOG_NOADV_CA); 1816 } 1817 } 1818 } 1819 } else { 1820 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 1821 sctp_log_cwnd(stcb, net, net->mtu, 1822 SCTP_CWND_LOG_NO_CUMACK); 1823 } 1824 } 1825 } 1826 } 1827 1828 1829 /* 1830 * H-TCP congestion control. The algorithm is detailed in: 1831 * R.N.Shorten, D.J.Leith: 1832 * "H-TCP: TCP for high-speed and long-distance networks" 1833 * Proc. PFLDnet, Argonne, 2004. 1834 * http://www.hamilton.ie/net/htcp3.pdf 1835 */ 1836 1837 1838 static int use_rtt_scaling = 1; 1839 static int use_bandwidth_switch = 1; 1840 1841 static inline int 1842 between(uint32_t seq1, uint32_t seq2, uint32_t seq3) 1843 { 1844 return seq3 - seq2 >= seq1 - seq2; 1845 } 1846 1847 static inline uint32_t 1848 htcp_cong_time(struct htcp *ca) 1849 { 1850 return sctp_get_tick_count() - ca->last_cong; 1851 } 1852 1853 static inline uint32_t 1854 htcp_ccount(struct htcp *ca) 1855 { 1856 return htcp_cong_time(ca) / ca->minRTT; 1857 } 1858 1859 static inline void 1860 htcp_reset(struct htcp *ca) 1861 { 1862 ca->undo_last_cong = ca->last_cong; 1863 ca->undo_maxRTT = ca->maxRTT; 1864 ca->undo_old_maxB = ca->old_maxB; 1865 ca->last_cong = sctp_get_tick_count(); 1866 } 1867 1868 #ifdef SCTP_NOT_USED 1869 1870 static uint32_t 1871 htcp_cwnd_undo(struct sctp_tcb *stcb, struct sctp_nets *net) 1872 { 1873 net->cc_mod.htcp_ca.last_cong = net->cc_mod.htcp_ca.undo_last_cong; 1874 net->cc_mod.htcp_ca.maxRTT = net->cc_mod.htcp_ca.undo_maxRTT; 1875 net->cc_mod.htcp_ca.old_maxB = net->cc_mod.htcp_ca.undo_old_maxB; 1876 return max(net->cwnd, ((net->ssthresh / net->mtu << 7) / net->cc_mod.htcp_ca.beta) * net->mtu); 1877 } 1878 1879 #endif 1880 1881 static inline void 1882 measure_rtt(struct sctp_tcb *stcb, struct sctp_nets *net) 1883 { 1884 uint32_t srtt = net->lastsa >> SCTP_RTT_SHIFT; 1885 1886 /* keep track of minimum RTT seen so far, minRTT is zero at first */ 1887 if (net->cc_mod.htcp_ca.minRTT > srtt || !net->cc_mod.htcp_ca.minRTT) 1888 net->cc_mod.htcp_ca.minRTT = srtt; 1889 1890 /* max RTT */ 1891 if (net->fast_retran_ip == 0 && net->ssthresh < 0xFFFF && htcp_ccount(&net->cc_mod.htcp_ca) > 3) { 1892 if (net->cc_mod.htcp_ca.maxRTT < net->cc_mod.htcp_ca.minRTT) 1893 net->cc_mod.htcp_ca.maxRTT = net->cc_mod.htcp_ca.minRTT; 1894 if (net->cc_mod.htcp_ca.maxRTT < srtt && srtt <= net->cc_mod.htcp_ca.maxRTT + MSEC_TO_TICKS(20)) 1895 net->cc_mod.htcp_ca.maxRTT = srtt; 1896 } 1897 } 1898 1899 static void 1900 measure_achieved_throughput(struct sctp_tcb *stcb, struct sctp_nets *net) 1901 { 1902 uint32_t now = sctp_get_tick_count(); 1903 1904 if (net->fast_retran_ip == 0) 1905 net->cc_mod.htcp_ca.bytes_acked = net->net_ack; 1906 1907 if (!use_bandwidth_switch) 1908 return; 1909 1910 /* achieved throughput calculations */ 1911 /* JRS - not 100% sure of this statement */ 1912 if (net->fast_retran_ip == 1) { 1913 net->cc_mod.htcp_ca.bytecount = 0; 1914 net->cc_mod.htcp_ca.lasttime = now; 1915 return; 1916 } 1917 net->cc_mod.htcp_ca.bytecount += net->net_ack; 1918 1919 if (net->cc_mod.htcp_ca.bytecount >= net->cwnd - ((net->cc_mod.htcp_ca.alpha >> 7 ? : 1) * net->mtu) 1920 && now - net->cc_mod.htcp_ca.lasttime >= net->cc_mod.htcp_ca.minRTT 1921 && net->cc_mod.htcp_ca.minRTT > 0) { 1922 uint32_t cur_Bi = net->cc_mod.htcp_ca.bytecount / net->mtu * hz / (now - net->cc_mod.htcp_ca.lasttime); 1923 1924 if (htcp_ccount(&net->cc_mod.htcp_ca) <= 3) { 1925 /* just after backoff */ 1926 net->cc_mod.htcp_ca.minB = net->cc_mod.htcp_ca.maxB = net->cc_mod.htcp_ca.Bi = cur_Bi; 1927 } else { 1928 net->cc_mod.htcp_ca.Bi = (3 * net->cc_mod.htcp_ca.Bi + cur_Bi) / 4; 1929 if (net->cc_mod.htcp_ca.Bi > net->cc_mod.htcp_ca.maxB) 1930 net->cc_mod.htcp_ca.maxB = net->cc_mod.htcp_ca.Bi; 1931 if (net->cc_mod.htcp_ca.minB > net->cc_mod.htcp_ca.maxB) 1932 net->cc_mod.htcp_ca.minB = net->cc_mod.htcp_ca.maxB; 1933 } 1934 net->cc_mod.htcp_ca.bytecount = 0; 1935 net->cc_mod.htcp_ca.lasttime = now; 1936 } 1937 } 1938 1939 static inline void 1940 htcp_beta_update(struct htcp *ca, uint32_t minRTT, uint32_t maxRTT) 1941 { 1942 if (use_bandwidth_switch) { 1943 uint32_t maxB = ca->maxB; 1944 uint32_t old_maxB = ca->old_maxB; 1945 1946 ca->old_maxB = ca->maxB; 1947 1948 if (!between(5 * maxB, 4 * old_maxB, 6 * old_maxB)) { 1949 ca->beta = BETA_MIN; 1950 ca->modeswitch = 0; 1951 return; 1952 } 1953 } 1954 if (ca->modeswitch && minRTT > (uint32_t) MSEC_TO_TICKS(10) && maxRTT) { 1955 ca->beta = (minRTT << 7) / maxRTT; 1956 if (ca->beta < BETA_MIN) 1957 ca->beta = BETA_MIN; 1958 else if (ca->beta > BETA_MAX) 1959 ca->beta = BETA_MAX; 1960 } else { 1961 ca->beta = BETA_MIN; 1962 ca->modeswitch = 1; 1963 } 1964 } 1965 1966 static inline void 1967 htcp_alpha_update(struct htcp *ca) 1968 { 1969 uint32_t minRTT = ca->minRTT; 1970 uint32_t factor = 1; 1971 uint32_t diff = htcp_cong_time(ca); 1972 1973 if (diff > (uint32_t) hz) { 1974 diff -= hz; 1975 factor = 1 + (10 * diff + ((diff / 2) * (diff / 2) / hz)) / hz; 1976 } 1977 if (use_rtt_scaling && minRTT) { 1978 uint32_t scale = (hz << 3) / (10 * minRTT); 1979 1980 scale = min(max(scale, 1U << 2), 10U << 3); /* clamping ratio to 1981 * interval [0.5,10]<<3 */ 1982 factor = (factor << 3) / scale; 1983 if (!factor) 1984 factor = 1; 1985 } 1986 ca->alpha = 2 * factor * ((1 << 7) - ca->beta); 1987 if (!ca->alpha) 1988 ca->alpha = ALPHA_BASE; 1989 } 1990 1991 /* After we have the rtt data to calculate beta, we'd still prefer to wait one 1992 * rtt before we adjust our beta to ensure we are working from a consistent 1993 * data. 1994 * 1995 * This function should be called when we hit a congestion event since only at 1996 * that point do we really have a real sense of maxRTT (the queues en route 1997 * were getting just too full now). 1998 */ 1999 static void 2000 htcp_param_update(struct sctp_tcb *stcb, struct sctp_nets *net) 2001 { 2002 uint32_t minRTT = net->cc_mod.htcp_ca.minRTT; 2003 uint32_t maxRTT = net->cc_mod.htcp_ca.maxRTT; 2004 2005 htcp_beta_update(&net->cc_mod.htcp_ca, minRTT, maxRTT); 2006 htcp_alpha_update(&net->cc_mod.htcp_ca); 2007 2008 /* 2009 * add slowly fading memory for maxRTT to accommodate routing 2010 * changes etc 2011 */ 2012 if (minRTT > 0 && maxRTT > minRTT) 2013 net->cc_mod.htcp_ca.maxRTT = minRTT + ((maxRTT - minRTT) * 95) / 100; 2014 } 2015 2016 static uint32_t 2017 htcp_recalc_ssthresh(struct sctp_tcb *stcb, struct sctp_nets *net) 2018 { 2019 htcp_param_update(stcb, net); 2020 return max(((net->cwnd / net->mtu * net->cc_mod.htcp_ca.beta) >> 7) * net->mtu, 2U * net->mtu); 2021 } 2022 2023 static void 2024 htcp_cong_avoid(struct sctp_tcb *stcb, struct sctp_nets *net) 2025 { 2026 /*- 2027 * How to handle these functions? 2028 * if (!tcp_is_cwnd_limited(sk, in_flight)) RRS - good question. 2029 * return; 2030 */ 2031 if (net->cwnd <= net->ssthresh) { 2032 /* We are in slow start */ 2033 if (net->flight_size + net->net_ack >= net->cwnd) { 2034 if (net->net_ack > (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable))) { 2035 net->cwnd += (net->mtu * SCTP_BASE_SYSCTL(sctp_L2_abc_variable)); 2036 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2037 sctp_log_cwnd(stcb, net, net->mtu, 2038 SCTP_CWND_LOG_FROM_SS); 2039 } 2040 } else { 2041 net->cwnd += net->net_ack; 2042 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2043 sctp_log_cwnd(stcb, net, net->net_ack, 2044 SCTP_CWND_LOG_FROM_SS); 2045 } 2046 } 2047 } else { 2048 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 2049 sctp_log_cwnd(stcb, net, net->net_ack, 2050 SCTP_CWND_LOG_NOADV_SS); 2051 } 2052 } 2053 } else { 2054 measure_rtt(stcb, net); 2055 2056 /* 2057 * In dangerous area, increase slowly. In theory this is 2058 * net->cwnd += alpha / net->cwnd 2059 */ 2060 /* What is snd_cwnd_cnt?? */ 2061 if (((net->partial_bytes_acked / net->mtu * net->cc_mod.htcp_ca.alpha) >> 7) * net->mtu >= net->cwnd) { 2062 /*- 2063 * Does SCTP have a cwnd clamp? 2064 * if (net->snd_cwnd < net->snd_cwnd_clamp) - Nope (RRS). 2065 */ 2066 net->cwnd += net->mtu; 2067 net->partial_bytes_acked = 0; 2068 htcp_alpha_update(&net->cc_mod.htcp_ca); 2069 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2070 sctp_log_cwnd(stcb, net, net->mtu, 2071 SCTP_CWND_LOG_FROM_CA); 2072 } 2073 } else { 2074 net->partial_bytes_acked += net->net_ack; 2075 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 2076 sctp_log_cwnd(stcb, net, net->net_ack, 2077 SCTP_CWND_LOG_NOADV_CA); 2078 } 2079 } 2080 2081 net->cc_mod.htcp_ca.bytes_acked = net->mtu; 2082 } 2083 } 2084 2085 #ifdef SCTP_NOT_USED 2086 /* Lower bound on congestion window. */ 2087 static uint32_t 2088 htcp_min_cwnd(struct sctp_tcb *stcb, struct sctp_nets *net) 2089 { 2090 return net->ssthresh; 2091 } 2092 2093 #endif 2094 2095 static void 2096 htcp_init(struct sctp_tcb *stcb, struct sctp_nets *net) 2097 { 2098 memset(&net->cc_mod.htcp_ca, 0, sizeof(struct htcp)); 2099 net->cc_mod.htcp_ca.alpha = ALPHA_BASE; 2100 net->cc_mod.htcp_ca.beta = BETA_MIN; 2101 net->cc_mod.htcp_ca.bytes_acked = net->mtu; 2102 net->cc_mod.htcp_ca.last_cong = sctp_get_tick_count(); 2103 } 2104 2105 static void 2106 sctp_htcp_set_initial_cc_param(struct sctp_tcb *stcb, struct sctp_nets *net) 2107 { 2108 /* 2109 * We take the max of the burst limit times a MTU or the 2110 * INITIAL_CWND. We then limit this to 4 MTU's of sending. 2111 */ 2112 net->cwnd = min((net->mtu * 4), max((2 * net->mtu), SCTP_INITIAL_CWND)); 2113 net->ssthresh = stcb->asoc.peers_rwnd; 2114 htcp_init(stcb, net); 2115 2116 if (SCTP_BASE_SYSCTL(sctp_logging_level) & (SCTP_CWND_MONITOR_ENABLE | SCTP_CWND_LOGGING_ENABLE)) { 2117 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_INITIALIZATION); 2118 } 2119 } 2120 2121 static void 2122 sctp_htcp_cwnd_update_after_sack(struct sctp_tcb *stcb, 2123 struct sctp_association *asoc, 2124 int accum_moved, int reneged_all, int will_exit) 2125 { 2126 struct sctp_nets *net; 2127 2128 /******************************/ 2129 /* update cwnd and Early FR */ 2130 /******************************/ 2131 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 2132 2133 #ifdef JANA_CMT_FAST_RECOVERY 2134 /* 2135 * CMT fast recovery code. Need to debug. 2136 */ 2137 if (net->fast_retran_loss_recovery && net->new_pseudo_cumack) { 2138 if (SCTP_TSN_GE(asoc->last_acked_seq, net->fast_recovery_tsn) || 2139 SCTP_TSN_GE(net->pseudo_cumack, net->fast_recovery_tsn)) { 2140 net->will_exit_fast_recovery = 1; 2141 } 2142 } 2143 #endif 2144 /* if nothing was acked on this destination skip it */ 2145 if (net->net_ack == 0) { 2146 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 2147 sctp_log_cwnd(stcb, net, 0, SCTP_CWND_LOG_FROM_SACK); 2148 } 2149 continue; 2150 } 2151 #ifdef JANA_CMT_FAST_RECOVERY 2152 /* 2153 * CMT fast recovery code 2154 */ 2155 /* 2156 * if (sctp_cmt_on_off > 0 && net->fast_retran_loss_recovery 2157 * && net->will_exit_fast_recovery == 0) { @@@ Do something 2158 * } else if (sctp_cmt_on_off == 0 && 2159 * asoc->fast_retran_loss_recovery && will_exit == 0) { 2160 */ 2161 #endif 2162 2163 if (asoc->fast_retran_loss_recovery && 2164 will_exit == 0 && 2165 (asoc->sctp_cmt_on_off == 0)) { 2166 /* 2167 * If we are in loss recovery we skip any cwnd 2168 * update 2169 */ 2170 return; 2171 } 2172 /* 2173 * CMT: CUC algorithm. Update cwnd if pseudo-cumack has 2174 * moved. 2175 */ 2176 if (accum_moved || 2177 ((asoc->sctp_cmt_on_off > 0) && net->new_pseudo_cumack)) { 2178 htcp_cong_avoid(stcb, net); 2179 measure_achieved_throughput(stcb, net); 2180 } else { 2181 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { 2182 sctp_log_cwnd(stcb, net, net->mtu, 2183 SCTP_CWND_LOG_NO_CUMACK); 2184 } 2185 } 2186 } 2187 } 2188 2189 static void 2190 sctp_htcp_cwnd_update_after_fr(struct sctp_tcb *stcb, 2191 struct sctp_association *asoc) 2192 { 2193 struct sctp_nets *net; 2194 2195 /* 2196 * CMT fast recovery code. Need to debug. ((sctp_cmt_on_off > 0) && 2197 * (net->fast_retran_loss_recovery == 0))) 2198 */ 2199 TAILQ_FOREACH(net, &asoc->nets, sctp_next) { 2200 if ((asoc->fast_retran_loss_recovery == 0) || 2201 (asoc->sctp_cmt_on_off > 0)) { 2202 /* out of a RFC2582 Fast recovery window? */ 2203 if (net->net_ack > 0) { 2204 /* 2205 * per section 7.2.3, are there any 2206 * destinations that had a fast retransmit 2207 * to them. If so what we need to do is 2208 * adjust ssthresh and cwnd. 2209 */ 2210 struct sctp_tmit_chunk *lchk; 2211 int old_cwnd = net->cwnd; 2212 2213 /* JRS - reset as if state were changed */ 2214 htcp_reset(&net->cc_mod.htcp_ca); 2215 net->ssthresh = htcp_recalc_ssthresh(stcb, net); 2216 net->cwnd = net->ssthresh; 2217 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2218 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), 2219 SCTP_CWND_LOG_FROM_FR); 2220 } 2221 lchk = TAILQ_FIRST(&asoc->send_queue); 2222 2223 net->partial_bytes_acked = 0; 2224 /* Turn on fast recovery window */ 2225 asoc->fast_retran_loss_recovery = 1; 2226 if (lchk == NULL) { 2227 /* Mark end of the window */ 2228 asoc->fast_recovery_tsn = asoc->sending_seq - 1; 2229 } else { 2230 asoc->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 2231 } 2232 2233 /* 2234 * CMT fast recovery -- per destination 2235 * recovery variable. 2236 */ 2237 net->fast_retran_loss_recovery = 1; 2238 2239 if (lchk == NULL) { 2240 /* Mark end of the window */ 2241 net->fast_recovery_tsn = asoc->sending_seq - 1; 2242 } else { 2243 net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1; 2244 } 2245 2246 sctp_timer_stop(SCTP_TIMER_TYPE_SEND, 2247 stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32); 2248 sctp_timer_start(SCTP_TIMER_TYPE_SEND, 2249 stcb->sctp_ep, stcb, net); 2250 } 2251 } else if (net->net_ack > 0) { 2252 /* 2253 * Mark a peg that we WOULD have done a cwnd 2254 * reduction but RFC2582 prevented this action. 2255 */ 2256 SCTP_STAT_INCR(sctps_fastretransinrtt); 2257 } 2258 } 2259 } 2260 2261 static void 2262 sctp_htcp_cwnd_update_after_timeout(struct sctp_tcb *stcb, 2263 struct sctp_nets *net) 2264 { 2265 int old_cwnd = net->cwnd; 2266 2267 /* JRS - reset as if the state were being changed to timeout */ 2268 htcp_reset(&net->cc_mod.htcp_ca); 2269 net->ssthresh = htcp_recalc_ssthresh(stcb, net); 2270 net->cwnd = net->mtu; 2271 net->partial_bytes_acked = 0; 2272 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2273 sctp_log_cwnd(stcb, net, net->cwnd - old_cwnd, SCTP_CWND_LOG_FROM_RTX); 2274 } 2275 } 2276 2277 static void 2278 sctp_htcp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, 2279 struct sctp_nets *net, int in_window, int num_pkt_lost) 2280 { 2281 int old_cwnd; 2282 2283 old_cwnd = net->cwnd; 2284 2285 /* JRS - reset hctp as if state changed */ 2286 if (in_window == 0) { 2287 htcp_reset(&net->cc_mod.htcp_ca); 2288 SCTP_STAT_INCR(sctps_ecnereducedcwnd); 2289 net->ssthresh = htcp_recalc_ssthresh(stcb, net); 2290 if (net->ssthresh < net->mtu) { 2291 net->ssthresh = net->mtu; 2292 /* here back off the timer as well, to slow us down */ 2293 net->RTO <<= 1; 2294 } 2295 net->cwnd = net->ssthresh; 2296 if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) { 2297 sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT); 2298 } 2299 } 2300 } 2301 2302 struct sctp_cc_functions sctp_cc_functions[] = { 2303 { 2304 .sctp_set_initial_cc_param = sctp_set_initial_cc_param, 2305 .sctp_cwnd_update_after_sack = sctp_cwnd_update_after_sack, 2306 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common, 2307 .sctp_cwnd_update_after_fr = sctp_cwnd_update_after_fr, 2308 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout, 2309 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_after_ecn_echo, 2310 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped, 2311 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output, 2312 }, 2313 { 2314 .sctp_set_initial_cc_param = sctp_set_initial_cc_param, 2315 .sctp_cwnd_update_after_sack = sctp_hs_cwnd_update_after_sack, 2316 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common, 2317 .sctp_cwnd_update_after_fr = sctp_hs_cwnd_update_after_fr, 2318 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout, 2319 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_after_ecn_echo, 2320 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped, 2321 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output, 2322 }, 2323 { 2324 .sctp_set_initial_cc_param = sctp_htcp_set_initial_cc_param, 2325 .sctp_cwnd_update_after_sack = sctp_htcp_cwnd_update_after_sack, 2326 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common, 2327 .sctp_cwnd_update_after_fr = sctp_htcp_cwnd_update_after_fr, 2328 .sctp_cwnd_update_after_timeout = sctp_htcp_cwnd_update_after_timeout, 2329 .sctp_cwnd_update_after_ecn_echo = sctp_htcp_cwnd_update_after_ecn_echo, 2330 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped, 2331 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output, 2332 }, 2333 { 2334 .sctp_set_initial_cc_param = sctp_set_rtcc_initial_cc_param, 2335 .sctp_cwnd_update_after_sack = sctp_cwnd_update_rtcc_after_sack, 2336 .sctp_cwnd_update_exit_pf = sctp_cwnd_update_exit_pf_common, 2337 .sctp_cwnd_update_after_fr = sctp_cwnd_update_after_fr, 2338 .sctp_cwnd_update_after_timeout = sctp_cwnd_update_after_timeout, 2339 .sctp_cwnd_update_after_ecn_echo = sctp_cwnd_update_rtcc_after_ecn_echo, 2340 .sctp_cwnd_update_after_packet_dropped = sctp_cwnd_update_after_packet_dropped, 2341 .sctp_cwnd_update_after_output = sctp_cwnd_update_after_output, 2342 .sctp_cwnd_update_packet_transmitted = sctp_cwnd_update_rtcc_packet_transmitted, 2343 .sctp_cwnd_update_tsn_acknowledged = sctp_cwnd_update_rtcc_tsn_acknowledged, 2344 .sctp_cwnd_new_transmission_begins = sctp_cwnd_new_rtcc_transmission_begins, 2345 .sctp_cwnd_prepare_net_for_sack = sctp_cwnd_prepare_rtcc_net_for_sack, 2346 .sctp_cwnd_socket_option = sctp_cwnd_rtcc_socket_option, 2347 .sctp_rtt_calculated = sctp_rtt_rtcc_calculated 2348 } 2349 };
Cache object: 2fbe911bbd3cfd1d7e8a0e894a41846b
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