sample.c revision 218160
1/*- 2 * Copyright (c) 2005 John Bicket 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer, 10 * without modification. 11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 12 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 13 * redistribution must be conditioned upon including a substantially 14 * similar Disclaimer requirement for further binary redistribution. 15 * 3. Neither the names of the above-listed copyright holders nor the names 16 * of any contributors may be used to endorse or promote products derived 17 * from this software without specific prior written permission. 18 * 19 * Alternatively, this software may be distributed under the terms of the 20 * GNU General Public License ("GPL") version 2 as published by the Free 21 * Software Foundation. 22 * 23 * NO WARRANTY 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 25 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 26 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 27 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 28 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 29 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 32 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 34 * THE POSSIBILITY OF SUCH DAMAGES. 35 * 36 */ 37 38#include <sys/cdefs.h> 39__FBSDID("$FreeBSD: head/sys/dev/ath/ath_rate/sample/sample.c 218160 2011-02-01 08:10:18Z adrian $"); 40 41/* 42 * John Bicket's SampleRate control algorithm. 43 */ 44#include "opt_inet.h" 45#include "opt_wlan.h" 46 47#include <sys/param.h> 48#include <sys/systm.h> 49#include <sys/sysctl.h> 50#include <sys/kernel.h> 51#include <sys/lock.h> 52#include <sys/mutex.h> 53#include <sys/errno.h> 54 55#include <machine/bus.h> 56#include <machine/resource.h> 57#include <sys/bus.h> 58 59#include <sys/socket.h> 60 61#include <net/if.h> 62#include <net/if_media.h> 63#include <net/if_arp.h> 64#include <net/ethernet.h> /* XXX for ether_sprintf */ 65 66#include <net80211/ieee80211_var.h> 67 68#include <net/bpf.h> 69 70#ifdef INET 71#include <netinet/in.h> 72#include <netinet/if_ether.h> 73#endif 74 75#include <dev/ath/if_athvar.h> 76#include <dev/ath/ath_rate/sample/sample.h> 77#include <dev/ath/ath_hal/ah_desc.h> 78#include <dev/ath/ath_rate/sample/tx_schedules.h> 79 80/* 81 * This file is an implementation of the SampleRate algorithm 82 * in "Bit-rate Selection in Wireless Networks" 83 * (http://www.pdos.lcs.mit.edu/papers/jbicket-ms.ps) 84 * 85 * SampleRate chooses the bit-rate it predicts will provide the most 86 * throughput based on estimates of the expected per-packet 87 * transmission time for each bit-rate. SampleRate periodically sends 88 * packets at bit-rates other than the current one to estimate when 89 * another bit-rate will provide better performance. SampleRate 90 * switches to another bit-rate when its estimated per-packet 91 * transmission time becomes smaller than the current bit-rate's. 92 * SampleRate reduces the number of bit-rates it must sample by 93 * eliminating those that could not perform better than the one 94 * currently being used. SampleRate also stops probing at a bit-rate 95 * if it experiences several successive losses. 96 * 97 * The difference between the algorithm in the thesis and the one in this 98 * file is that the one in this file uses a ewma instead of a window. 99 * 100 * Also, this implementation tracks the average transmission time for 101 * a few different packet sizes independently for each link. 102 */ 103 104static void ath_rate_ctl_reset(struct ath_softc *, struct ieee80211_node *); 105 106static const int packet_size_bins[NUM_PACKET_SIZE_BINS] = { 250, 1600 }; 107 108static __inline int 109size_to_bin(int size) 110{ 111#if NUM_PACKET_SIZE_BINS > 1 112 if (size <= packet_size_bins[0]) 113 return 0; 114#endif 115#if NUM_PACKET_SIZE_BINS > 2 116 if (size <= packet_size_bins[1]) 117 return 1; 118#endif 119#if NUM_PACKET_SIZE_BINS > 3 120 if (size <= packet_size_bins[2]) 121 return 2; 122#endif 123#if NUM_PACKET_SIZE_BINS > 4 124#error "add support for more packet sizes" 125#endif 126 return NUM_PACKET_SIZE_BINS-1; 127} 128 129static __inline int 130bin_to_size(int index) 131{ 132 return packet_size_bins[index]; 133} 134 135void 136ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 137{ 138 /* NB: assumed to be zero'd by caller */ 139} 140 141void 142ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 143{ 144} 145 146static int 147dot11rate(const HAL_RATE_TABLE *rt, int rix) 148{ 149 return rt->info[rix].phy == IEEE80211_T_HT ? 150 rt->info[rix].dot11Rate : (rt->info[rix].dot11Rate & IEEE80211_RATE_VAL) / 2; 151} 152 153/* 154 * Return the rix with the lowest average_tx_time, 155 * or -1 if all the average_tx_times are 0. 156 */ 157static __inline int 158pick_best_rate(struct sample_node *sn, const HAL_RATE_TABLE *rt, 159 int size_bin, int require_acked_before) 160{ 161 int best_rate_rix, best_rate_tt; 162 uint32_t mask; 163 int rix, tt; 164 165 best_rate_rix = 0; 166 best_rate_tt = 0; 167 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 168 if ((mask & 1) == 0) /* not a supported rate */ 169 continue; 170 171 tt = sn->stats[size_bin][rix].average_tx_time; 172 if (tt <= 0 || 173 (require_acked_before && 174 !sn->stats[size_bin][rix].packets_acked)) 175 continue; 176 177 /* don't use a bit-rate that has been failing */ 178 if (sn->stats[size_bin][rix].successive_failures > 3) 179 continue; 180 181 if (best_rate_tt == 0 || tt < best_rate_tt) { 182 best_rate_tt = tt; 183 best_rate_rix = rix; 184 } 185 } 186 return (best_rate_tt ? best_rate_rix : -1); 187} 188 189/* 190 * Pick a good "random" bit-rate to sample other than the current one. 191 */ 192static __inline int 193pick_sample_rate(struct sample_softc *ssc , struct sample_node *sn, 194 const HAL_RATE_TABLE *rt, int size_bin) 195{ 196#define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) 197#define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) 198 int current_rix, rix; 199 unsigned current_tt; 200 uint32_t mask; 201 202 current_rix = sn->current_rix[size_bin]; 203 if (current_rix < 0) { 204 /* no successes yet, send at the lowest bit-rate */ 205 return 0; 206 } 207 208 current_tt = sn->stats[size_bin][current_rix].average_tx_time; 209 210 rix = sn->last_sample_rix[size_bin]+1; /* next sample rate */ 211 mask = sn->ratemask &~ (1<<current_rix);/* don't sample current rate */ 212 while (mask != 0) { 213 if ((mask & (1<<rix)) == 0) { /* not a supported rate */ 214 nextrate: 215 if (++rix >= rt->rateCount) 216 rix = 0; 217 continue; 218 } 219 220 /* this bit-rate is always worse than the current one */ 221 if (sn->stats[size_bin][rix].perfect_tx_time > current_tt) { 222 mask &= ~(1<<rix); 223 goto nextrate; 224 } 225 226 /* rarely sample bit-rates that fail a lot */ 227 if (sn->stats[size_bin][rix].successive_failures > ssc->max_successive_failures && 228 ticks - sn->stats[size_bin][rix].last_tx < ssc->stale_failure_timeout) { 229 mask &= ~(1<<rix); 230 goto nextrate; 231 } 232 233 /* don't sample more than 2 rates higher for rates > 11M */ 234 if (DOT11RATE(rix) > 2*11 && rix > current_rix + 2) { 235 mask &= ~(1<<rix); 236 goto nextrate; 237 } 238 239 sn->last_sample_rix[size_bin] = rix; 240 return rix; 241 } 242 return current_rix; 243#undef DOT11RATE 244#undef MCS 245} 246 247void 248ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 249 int shortPreamble, size_t frameLen, 250 u_int8_t *rix0, int *try0, u_int8_t *txrate) 251{ 252#define DOT11RATE(ix) (rt->info[ix].dot11Rate & IEEE80211_RATE_VAL) 253#define MCS(ix) (rt->info[ix].dot11Rate | IEEE80211_RATE_MCS) 254#define RATE(ix) (DOT11RATE(ix) / 2) 255 struct sample_node *sn = ATH_NODE_SAMPLE(an); 256 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); 257 struct ifnet *ifp = sc->sc_ifp; 258 struct ieee80211com *ic = ifp->if_l2com; 259 const HAL_RATE_TABLE *rt = sc->sc_currates; 260 const int size_bin = size_to_bin(frameLen); 261 int rix, mrr, best_rix, change_rates; 262 unsigned average_tx_time; 263 264 if (sn->static_rix != -1) { 265 rix = sn->static_rix; 266 *try0 = ATH_TXMAXTRY; 267 goto done; 268 } 269 270 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); 271 272 best_rix = pick_best_rate(sn, rt, size_bin, !mrr); 273 if (best_rix >= 0) { 274 average_tx_time = sn->stats[size_bin][best_rix].average_tx_time; 275 } else { 276 average_tx_time = 0; 277 } 278 /* 279 * Limit the time measuring the performance of other tx 280 * rates to sample_rate% of the total transmission time. 281 */ 282 if (sn->sample_tt[size_bin] < average_tx_time * (sn->packets_since_sample[size_bin]*ssc->sample_rate/100)) { 283 rix = pick_sample_rate(ssc, sn, rt, size_bin); 284 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 285 &an->an_node, "size %u sample rate %d current rate %d", 286 bin_to_size(size_bin), RATE(rix), 287 RATE(sn->current_rix[size_bin])); 288 if (rix != sn->current_rix[size_bin]) { 289 sn->current_sample_rix[size_bin] = rix; 290 } else { 291 sn->current_sample_rix[size_bin] = -1; 292 } 293 sn->packets_since_sample[size_bin] = 0; 294 } else { 295 change_rates = 0; 296 if (!sn->packets_sent[size_bin] || best_rix == -1) { 297 /* no packet has been sent successfully yet */ 298 for (rix = rt->rateCount-1; rix > 0; rix--) { 299 if ((sn->ratemask & (1<<rix)) == 0) 300 continue; 301 /* 302 * Pick the highest rate <= 36 Mbps 303 * that hasn't failed. 304 */ 305 if (DOT11RATE(rix) <= 72 && 306 sn->stats[size_bin][rix].successive_failures == 0) { 307 break; 308 } 309 } 310 change_rates = 1; 311 best_rix = rix; 312 } else if (sn->packets_sent[size_bin] < 20) { 313 /* let the bit-rate switch quickly during the first few packets */ 314 change_rates = 1; 315 } else if (ticks - ssc->min_switch > sn->ticks_since_switch[size_bin]) { 316 /* min_switch seconds have gone by */ 317 change_rates = 1; 318 } else if (2*average_tx_time < sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time) { 319 /* the current bit-rate is twice as slow as the best one */ 320 change_rates = 1; 321 } 322 323 sn->packets_since_sample[size_bin]++; 324 325 if (change_rates) { 326 if (best_rix != sn->current_rix[size_bin]) { 327 IEEE80211_NOTE(an->an_node.ni_vap, 328 IEEE80211_MSG_RATECTL, 329 &an->an_node, 330"%s: size %d switch rate %d (%d/%d) -> %d (%d/%d) after %d packets mrr %d", 331 __func__, 332 bin_to_size(size_bin), 333 RATE(sn->current_rix[size_bin]), 334 sn->stats[size_bin][sn->current_rix[size_bin]].average_tx_time, 335 sn->stats[size_bin][sn->current_rix[size_bin]].perfect_tx_time, 336 RATE(best_rix), 337 sn->stats[size_bin][best_rix].average_tx_time, 338 sn->stats[size_bin][best_rix].perfect_tx_time, 339 sn->packets_since_switch[size_bin], 340 mrr); 341 } 342 sn->packets_since_switch[size_bin] = 0; 343 sn->current_rix[size_bin] = best_rix; 344 sn->ticks_since_switch[size_bin] = ticks; 345 /* 346 * Set the visible txrate for this node. 347 */ 348 an->an_node.ni_txrate = (rt->info[best_rix].phy == IEEE80211_T_HT) ? MCS(best_rix) : DOT11RATE(best_rix); 349 } 350 rix = sn->current_rix[size_bin]; 351 sn->packets_since_switch[size_bin]++; 352 } 353 *try0 = mrr ? sn->sched[rix].t0 : ATH_TXMAXTRY; 354done: 355 KASSERT(rix >= 0 && rix < rt->rateCount, ("rix is %d", rix)); 356 357 *rix0 = rix; 358 *txrate = rt->info[rix].rateCode 359 | (shortPreamble ? rt->info[rix].shortPreamble : 0); 360 sn->packets_sent[size_bin]++; 361#undef DOT11RATE 362#undef MCS 363#undef RATE 364} 365 366/* 367 * Get the TX rates. Don't fiddle with short preamble flags for them; 368 * the caller can do that. 369 */ 370void 371ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an, 372 uint8_t rix0, uint8_t *rix, uint8_t *try) 373{ 374 struct sample_node *sn = ATH_NODE_SAMPLE(an); 375 const struct txschedule *sched = &sn->sched[rix0]; 376 377 KASSERT(rix0 == sched->r0, ("rix0 (%x) != sched->r0 (%x)!\n", rix0, sched->r0)); 378 379/* rix[0] = sched->r0; */ 380 rix[1] = sched->r1; 381 rix[2] = sched->r2; 382 rix[3] = sched->r3; 383 384 try[0] = sched->t0; 385 try[1] = sched->t1; 386 try[2] = sched->t2; 387 try[3] = sched->t3; 388} 389 390void 391ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 392 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 393{ 394 struct sample_node *sn = ATH_NODE_SAMPLE(an); 395 const struct txschedule *sched = &sn->sched[rix]; 396 const HAL_RATE_TABLE *rt = sc->sc_currates; 397 uint8_t rix1, s1code, rix2, s2code, rix3, s3code; 398 399 /* XXX precalculate short preamble tables */ 400 rix1 = sched->r1; 401 s1code = rt->info[rix1].rateCode 402 | (shortPreamble ? rt->info[rix1].shortPreamble : 0); 403 rix2 = sched->r2; 404 s2code = rt->info[rix2].rateCode 405 | (shortPreamble ? rt->info[rix2].shortPreamble : 0); 406 rix3 = sched->r3; 407 s3code = rt->info[rix3].rateCode 408 | (shortPreamble ? rt->info[rix3].shortPreamble : 0); 409 ath_hal_setupxtxdesc(sc->sc_ah, ds, 410 s1code, sched->t1, /* series 1 */ 411 s2code, sched->t2, /* series 2 */ 412 s3code, sched->t3); /* series 3 */ 413} 414 415static void 416update_stats(struct ath_softc *sc, struct ath_node *an, 417 int frame_size, 418 int rix0, int tries0, 419 int rix1, int tries1, 420 int rix2, int tries2, 421 int rix3, int tries3, 422 int short_tries, int tries, int status) 423{ 424 struct sample_node *sn = ATH_NODE_SAMPLE(an); 425 struct sample_softc *ssc = ATH_SOFTC_SAMPLE(sc); 426 const int size_bin = size_to_bin(frame_size); 427 const int size = bin_to_size(size_bin); 428 int tt, tries_so_far; 429 430 if (!IS_RATE_DEFINED(sn, rix0)) 431 return; 432 tt = calc_usecs_unicast_packet(sc, size, rix0, short_tries, 433 MIN(tries0, tries) - 1); 434 tries_so_far = tries0; 435 436 if (tries1 && tries_so_far < tries) { 437 if (!IS_RATE_DEFINED(sn, rix1)) 438 return; 439 tt += calc_usecs_unicast_packet(sc, size, rix1, short_tries, 440 MIN(tries1 + tries_so_far, tries) - tries_so_far - 1); 441 tries_so_far += tries1; 442 } 443 444 if (tries2 && tries_so_far < tries) { 445 if (!IS_RATE_DEFINED(sn, rix2)) 446 return; 447 tt += calc_usecs_unicast_packet(sc, size, rix2, short_tries, 448 MIN(tries2 + tries_so_far, tries) - tries_so_far - 1); 449 tries_so_far += tries2; 450 } 451 452 if (tries3 && tries_so_far < tries) { 453 if (!IS_RATE_DEFINED(sn, rix3)) 454 return; 455 tt += calc_usecs_unicast_packet(sc, size, rix3, short_tries, 456 MIN(tries3 + tries_so_far, tries) - tries_so_far - 1); 457 } 458 459 if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) { 460 /* just average the first few packets */ 461 int avg_tx = sn->stats[size_bin][rix0].average_tx_time; 462 int packets = sn->stats[size_bin][rix0].total_packets; 463 sn->stats[size_bin][rix0].average_tx_time = (tt+(avg_tx*packets))/(packets+1); 464 } else { 465 /* use a ewma */ 466 sn->stats[size_bin][rix0].average_tx_time = 467 ((sn->stats[size_bin][rix0].average_tx_time * ssc->smoothing_rate) + 468 (tt * (100 - ssc->smoothing_rate))) / 100; 469 } 470 471 if (status != 0) { 472 int y; 473 sn->stats[size_bin][rix0].successive_failures++; 474 for (y = size_bin+1; y < NUM_PACKET_SIZE_BINS; y++) { 475 /* 476 * Also say larger packets failed since we 477 * assume if a small packet fails at a 478 * bit-rate then a larger one will also. 479 */ 480 sn->stats[y][rix0].successive_failures++; 481 sn->stats[y][rix0].last_tx = ticks; 482 sn->stats[y][rix0].tries += tries; 483 sn->stats[y][rix0].total_packets++; 484 } 485 } else { 486 sn->stats[size_bin][rix0].packets_acked++; 487 sn->stats[size_bin][rix0].successive_failures = 0; 488 } 489 sn->stats[size_bin][rix0].tries += tries; 490 sn->stats[size_bin][rix0].last_tx = ticks; 491 sn->stats[size_bin][rix0].total_packets++; 492 493 if (rix0 == sn->current_sample_rix[size_bin]) { 494 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 495 &an->an_node, 496"%s: size %d %s sample rate %d tries (%d/%d) tt %d avg_tt (%d/%d)", 497 __func__, 498 size, 499 status ? "FAIL" : "OK", 500 rix0, short_tries, tries, tt, 501 sn->stats[size_bin][rix0].average_tx_time, 502 sn->stats[size_bin][rix0].perfect_tx_time); 503 sn->sample_tt[size_bin] = tt; 504 sn->current_sample_rix[size_bin] = -1; 505 } 506} 507 508static void 509badrate(struct ifnet *ifp, int series, int hwrate, int tries, int status) 510{ 511 if_printf(ifp, "bad series%d hwrate 0x%x, tries %u ts_status 0x%x\n", 512 series, hwrate, tries, status); 513} 514 515void 516ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 517 const struct ath_buf *bf) 518{ 519 struct ifnet *ifp = sc->sc_ifp; 520 struct ieee80211com *ic = ifp->if_l2com; 521 struct sample_node *sn = ATH_NODE_SAMPLE(an); 522 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat; 523 const struct ath_desc *ds0 = &bf->bf_desc[0]; 524 int final_rix, short_tries, long_tries, frame_size; 525 const HAL_RATE_TABLE *rt = sc->sc_currates; 526 int mrr; 527 528 final_rix = rt->rateCodeToIndex[ts->ts_rate]; 529 short_tries = ts->ts_shortretry; 530 long_tries = ts->ts_longretry + 1; 531 frame_size = ds0->ds_ctl0 & 0x0fff; /* low-order 12 bits of ds_ctl0 */ 532 if (frame_size == 0) /* NB: should not happen */ 533 frame_size = 1500; 534 535 if (sn->ratemask == 0) { 536 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 537 &an->an_node, 538 "%s: size %d %s rate/try %d/%d no rates yet", 539 __func__, 540 bin_to_size(size_to_bin(frame_size)), 541 ts->ts_status ? "FAIL" : "OK", 542 short_tries, long_tries); 543 return; 544 } 545 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); 546 if (!mrr || ts->ts_finaltsi == 0) { 547 if (!IS_RATE_DEFINED(sn, final_rix)) { 548 badrate(ifp, 0, ts->ts_rate, long_tries, ts->ts_status); 549 return; 550 } 551 /* 552 * Only one rate was used; optimize work. 553 */ 554 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 555 &an->an_node, "%s: size %d %s rate/try %d/%d/%d", 556 __func__, 557 bin_to_size(size_to_bin(frame_size)), 558 ts->ts_status ? "FAIL" : "OK", 559 dot11rate(rt, final_rix), short_tries, long_tries); 560 update_stats(sc, an, frame_size, 561 final_rix, long_tries, 562 0, 0, 563 0, 0, 564 0, 0, 565 short_tries, long_tries, ts->ts_status); 566 } else { 567 int hwrates[4], tries[4], rix[4]; 568 int finalTSIdx = ts->ts_finaltsi; 569 int i; 570 571 /* 572 * Process intermediate rates that failed. 573 */ 574 ath_hal_gettxcompletionrates(sc->sc_ah, ds0, hwrates, tries); 575 576 for (i = 0; i < 4; i++) { 577 rix[i] = rt->rateCodeToIndex[hwrates[i]]; 578 } 579 580 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 581 &an->an_node, 582"%s: size %d finaltsidx %d tries %d %s rate/try [%d/%d %d/%d %d/%d %d/%d]", 583 __func__, 584 bin_to_size(size_to_bin(frame_size)), 585 finalTSIdx, 586 long_tries, 587 ts->ts_status ? "FAIL" : "OK", 588 dot11rate(rt, rix[0]), tries[0], 589 dot11rate(rt, rix[1]), tries[1], 590 dot11rate(rt, rix[2]), tries[2], 591 dot11rate(rt, rix[3]), tries[3]); 592 593 for (i = 0; i < 4; i++) { 594 if (tries[i] && !IS_RATE_DEFINED(sn, rix[i])) 595 badrate(ifp, 0, hwrates[i], tries[i], ts->ts_status); 596 } 597 598 /* 599 * NB: series > 0 are not penalized for failure 600 * based on the try counts under the assumption 601 * that losses are often bursty and since we 602 * sample higher rates 1 try at a time doing so 603 * may unfairly penalize them. 604 */ 605 if (tries[0]) { 606 update_stats(sc, an, frame_size, 607 rix[0], tries[0], 608 rix[1], tries[1], 609 rix[2], tries[2], 610 rix[3], tries[3], 611 short_tries, long_tries, 612 long_tries > tries[0]); 613 long_tries -= tries[0]; 614 } 615 616 if (tries[1] && finalTSIdx > 0) { 617 update_stats(sc, an, frame_size, 618 rix[1], tries[1], 619 rix[2], tries[2], 620 rix[3], tries[3], 621 0, 0, 622 short_tries, long_tries, 623 ts->ts_status); 624 long_tries -= tries[1]; 625 } 626 627 if (tries[2] && finalTSIdx > 1) { 628 update_stats(sc, an, frame_size, 629 rix[2], tries[2], 630 rix[3], tries[3], 631 0, 0, 632 0, 0, 633 short_tries, long_tries, 634 ts->ts_status); 635 long_tries -= tries[2]; 636 } 637 638 if (tries[3] && finalTSIdx > 2) { 639 update_stats(sc, an, frame_size, 640 rix[3], tries[3], 641 0, 0, 642 0, 0, 643 0, 0, 644 short_tries, long_tries, 645 ts->ts_status); 646 } 647 } 648} 649 650void 651ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 652{ 653 if (isnew) 654 ath_rate_ctl_reset(sc, &an->an_node); 655} 656 657static const struct txschedule *mrr_schedules[IEEE80211_MODE_MAX+2] = { 658 NULL, /* IEEE80211_MODE_AUTO */ 659 series_11a, /* IEEE80211_MODE_11A */ 660 series_11g, /* IEEE80211_MODE_11B */ 661 series_11g, /* IEEE80211_MODE_11G */ 662 NULL, /* IEEE80211_MODE_FH */ 663 series_11a, /* IEEE80211_MODE_TURBO_A */ 664 series_11g, /* IEEE80211_MODE_TURBO_G */ 665 series_11a, /* IEEE80211_MODE_STURBO_A */ 666 series_11na, /* IEEE80211_MODE_11NA */ 667 series_11ng, /* IEEE80211_MODE_11NG */ 668 series_half, /* IEEE80211_MODE_HALF */ 669 series_quarter, /* IEEE80211_MODE_QUARTER */ 670}; 671 672/* 673 * Initialize the tables for a node. 674 */ 675static void 676ath_rate_ctl_reset(struct ath_softc *sc, struct ieee80211_node *ni) 677{ 678#define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 679#define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL) 680#define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS) 681 682 struct ath_node *an = ATH_NODE(ni); 683 const struct ieee80211_txparam *tp = ni->ni_txparms; 684 struct sample_node *sn = ATH_NODE_SAMPLE(an); 685 const HAL_RATE_TABLE *rt = sc->sc_currates; 686 int x, y, srate, rix; 687 688 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 689 690 KASSERT(sc->sc_curmode < IEEE80211_MODE_MAX+2, 691 ("curmode %u", sc->sc_curmode)); 692 sn->sched = mrr_schedules[sc->sc_curmode]; 693 KASSERT(sn->sched != NULL, 694 ("no mrr schedule for mode %u", sc->sc_curmode)); 695 696 sn->static_rix = -1; 697 if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) { 698 /* 699 * A fixed rate is to be used; ucastrate is the IEEE code 700 * for this rate (sans basic bit). Check this against the 701 * negotiated rate set for the node. Note the fixed rate 702 * may not be available for various reasons so we only 703 * setup the static rate index if the lookup is successful. 704 */ 705 706 /* XXX todo: check MCS rates */ 707 708 /* Check legacy rates */ 709 for (srate = ni->ni_rates.rs_nrates - 1; srate >= 0; srate--) 710 if (RATE(srate) == tp->ucastrate) { 711 sn->static_rix = sc->sc_rixmap[tp->ucastrate]; 712 break; 713 } 714#ifdef IEEE80211_DEBUG 715 if (sn->static_rix == -1) { 716 IEEE80211_NOTE(ni->ni_vap, 717 IEEE80211_MSG_RATECTL, ni, 718 "%s: ucastrate %u not found, nrates %u", 719 __func__, tp->ucastrate, 720 ni->ni_rates.rs_nrates); 721 } 722#endif 723 } 724 725 /* 726 * Construct a bitmask of usable rates. This has all 727 * negotiated rates minus those marked by the hal as 728 * to be ignored for doing rate control. 729 */ 730 sn->ratemask = 0; 731 /* MCS rates */ 732 if (ni->ni_flags & IEEE80211_NODE_HT) { 733 for (x = 0; x < ni->ni_htrates.rs_nrates; x++) { 734 rix = sc->sc_rixmap[MCS(x)]; 735 if (rix == 0xff) 736 continue; 737 /* skip rates marked broken by hal */ 738 if (!rt->info[rix].valid) 739 continue; 740 KASSERT(rix < SAMPLE_MAXRATES, 741 ("mcs %u has rix %d", MCS(x), rix)); 742 sn->ratemask |= 1<<rix; 743 } 744 } 745 746 /* Legacy rates */ 747 for (x = 0; x < ni->ni_rates.rs_nrates; x++) { 748 rix = sc->sc_rixmap[RATE(x)]; 749 if (rix == 0xff) 750 continue; 751 /* skip rates marked broken by hal */ 752 if (!rt->info[rix].valid) 753 continue; 754 KASSERT(rix < SAMPLE_MAXRATES, 755 ("rate %u has rix %d", RATE(x), rix)); 756 sn->ratemask |= 1<<rix; 757 } 758#ifdef IEEE80211_DEBUG 759 if (ieee80211_msg(ni->ni_vap, IEEE80211_MSG_RATECTL)) { 760 uint32_t mask; 761 762 ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt", 763 ni->ni_macaddr, ":", __func__); 764 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 765 if ((mask & 1) == 0) 766 continue; 767 printf(" %d/%d", dot11rate(rt, rix), 768 calc_usecs_unicast_packet(sc, 1600, rix, 0,0)); 769 } 770 printf("\n"); 771 } 772#endif 773 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 774 int size = bin_to_size(y); 775 uint32_t mask; 776 777 sn->packets_sent[y] = 0; 778 sn->current_sample_rix[y] = -1; 779 sn->last_sample_rix[y] = 0; 780 /* XXX start with first valid rate */ 781 sn->current_rix[y] = ffs(sn->ratemask)-1; 782 783 /* 784 * Initialize the statistics buckets; these are 785 * indexed by the rate code index. 786 */ 787 for (rix = 0, mask = sn->ratemask; mask != 0; rix++, mask >>= 1) { 788 if ((mask & 1) == 0) /* not a valid rate */ 789 continue; 790 sn->stats[y][rix].successive_failures = 0; 791 sn->stats[y][rix].tries = 0; 792 sn->stats[y][rix].total_packets = 0; 793 sn->stats[y][rix].packets_acked = 0; 794 sn->stats[y][rix].last_tx = 0; 795 796 sn->stats[y][rix].perfect_tx_time = 797 calc_usecs_unicast_packet(sc, size, rix, 0, 0); 798 sn->stats[y][rix].average_tx_time = 799 sn->stats[y][rix].perfect_tx_time; 800 } 801 } 802#if 0 803 /* XXX 0, num_rates-1 are wrong */ 804 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 805 "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__, 806 sn->num_rates, 807 DOT11RATE(0)/2, DOT11RATE(0) % 1 ? ".5" : "", 808 sn->stats[1][0].perfect_tx_time, 809 DOT11RATE(sn->num_rates-1)/2, DOT11RATE(sn->num_rates-1) % 1 ? ".5" : "", 810 sn->stats[1][sn->num_rates-1].perfect_tx_time 811 ); 812#endif 813 /* set the visible bit-rate */ 814 if (sn->static_rix != -1) 815 ni->ni_txrate = DOT11RATE(sn->static_rix); 816 else 817 ni->ni_txrate = RATE(0); 818#undef RATE 819#undef DOT11RATE 820} 821 822static void 823sample_stats(void *arg, struct ieee80211_node *ni) 824{ 825 struct ath_softc *sc = arg; 826 const HAL_RATE_TABLE *rt = sc->sc_currates; 827 struct sample_node *sn = ATH_NODE_SAMPLE(ATH_NODE(ni)); 828 uint32_t mask; 829 int rix, y; 830 831 printf("\n[%s] refcnt %d static_rix %d ratemask 0x%x\n", 832 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni), 833 sn->static_rix, sn->ratemask); 834 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 835 printf("[%4u] cur rix %d since switch: packets %d ticks %u\n", 836 bin_to_size(y), sn->current_rix[y], 837 sn->packets_since_switch[y], sn->ticks_since_switch[y]); 838 printf("[%4u] last sample %d cur sample %d packets sent %d\n", 839 bin_to_size(y), sn->last_sample_rix[y], 840 sn->current_sample_rix[y], sn->packets_sent[y]); 841 printf("[%4u] packets since sample %d sample tt %u\n", 842 bin_to_size(y), sn->packets_since_sample[y], 843 sn->sample_tt[y]); 844 } 845 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 846 if ((mask & 1) == 0) 847 continue; 848 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 849 if (sn->stats[y][rix].total_packets == 0) 850 continue; 851 printf("[%2u:%4u] %8d:%-8d (%3d%%) T %8d F %4d avg %5u last %u\n", 852 dot11rate(rt, rix), 853 bin_to_size(y), 854 sn->stats[y][rix].total_packets, 855 sn->stats[y][rix].packets_acked, 856 (100*sn->stats[y][rix].packets_acked)/sn->stats[y][rix].total_packets, 857 sn->stats[y][rix].tries, 858 sn->stats[y][rix].successive_failures, 859 sn->stats[y][rix].average_tx_time, 860 ticks - sn->stats[y][rix].last_tx); 861 } 862 } 863} 864 865static int 866ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS) 867{ 868 struct ath_softc *sc = arg1; 869 struct ifnet *ifp = sc->sc_ifp; 870 struct ieee80211com *ic = ifp->if_l2com; 871 int error, v; 872 873 v = 0; 874 error = sysctl_handle_int(oidp, &v, 0, req); 875 if (error || !req->newptr) 876 return error; 877 ieee80211_iterate_nodes(&ic->ic_sta, sample_stats, sc); 878 return 0; 879} 880 881static int 882ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS) 883{ 884 struct sample_softc *ssc = arg1; 885 int rate, error; 886 887 rate = ssc->smoothing_rate; 888 error = sysctl_handle_int(oidp, &rate, 0, req); 889 if (error || !req->newptr) 890 return error; 891 if (!(0 <= rate && rate < 100)) 892 return EINVAL; 893 ssc->smoothing_rate = rate; 894 ssc->smoothing_minpackets = 100 / (100 - rate); 895 return 0; 896} 897 898static int 899ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS) 900{ 901 struct sample_softc *ssc = arg1; 902 int rate, error; 903 904 rate = ssc->sample_rate; 905 error = sysctl_handle_int(oidp, &rate, 0, req); 906 if (error || !req->newptr) 907 return error; 908 if (!(2 <= rate && rate <= 100)) 909 return EINVAL; 910 ssc->sample_rate = rate; 911 return 0; 912} 913 914static void 915ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *ssc) 916{ 917 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 918 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 919 920 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 921 "smoothing_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 922 ath_rate_sysctl_smoothing_rate, "I", 923 "sample: smoothing rate for avg tx time (%%)"); 924 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 925 "sample_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 926 ath_rate_sysctl_sample_rate, "I", 927 "sample: percent air time devoted to sampling new rates (%%)"); 928 /* XXX max_successive_failures, stale_failure_timeout, min_switch */ 929 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 930 "sample_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0, 931 ath_rate_sysctl_stats, "I", "sample: print statistics"); 932} 933 934struct ath_ratectrl * 935ath_rate_attach(struct ath_softc *sc) 936{ 937 struct sample_softc *ssc; 938 939 ssc = malloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 940 if (ssc == NULL) 941 return NULL; 942 ssc->arc.arc_space = sizeof(struct sample_node); 943 ssc->smoothing_rate = 95; /* ewma percentage ([0..99]) */ 944 ssc->smoothing_minpackets = 100 / (100 - ssc->smoothing_rate); 945 ssc->sample_rate = 10; /* %time to try diff tx rates */ 946 ssc->max_successive_failures = 3; /* threshold for rate sampling*/ 947 ssc->stale_failure_timeout = 10 * hz; /* 10 seconds */ 948 ssc->min_switch = hz; /* 1 second */ 949 ath_rate_sysctlattach(sc, ssc); 950 return &ssc->arc; 951} 952 953void 954ath_rate_detach(struct ath_ratectrl *arc) 955{ 956 struct sample_softc *ssc = (struct sample_softc *) arc; 957 958 free(ssc, M_DEVBUF); 959} 960