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("$FreeBSD$"); 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 */ 103 104 static void ath_rate_ctl_reset(struct ath_softc *, struct ieee80211_node *); 105 106 static const int packet_size_bins[NUM_PACKET_SIZE_BINS] = { 250, 1600 }; 107 108 static __inline int 109 size_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 } 128 129 static __inline int 130 bin_to_size(int index) 131 { 132 return packet_size_bins[index]; 133 } 134 135 void 136 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 137 { 138 /* NB: assumed to be zero'd by caller */ 139 } 140 141 void 142 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 143 { 144 } 145 146 static int 147 dot11rate(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 */ 157 static __inline int 158 pick_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 */ 192 static __inline int 193 pick_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 } 246 247 void 248 ath_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; 354 done: 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 */ 370 void 371 ath_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 } 389 390 void 391 ath_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 } 414 415 static void 416 update_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 int is_ht40 = (an->an_node.ni_htcap & IEEE80211_HTCAP_CHWIDTH40); 430 431 if (!IS_RATE_DEFINED(sn, rix0)) 432 return; 433 tt = calc_usecs_unicast_packet(sc, size, rix0, short_tries, 434 MIN(tries0, tries) - 1, is_ht40); 435 tries_so_far = tries0; 436 437 if (tries1 && tries_so_far < tries) { 438 if (!IS_RATE_DEFINED(sn, rix1)) 439 return; 440 tt += calc_usecs_unicast_packet(sc, size, rix1, short_tries, 441 MIN(tries1 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 442 tries_so_far += tries1; 443 } 444 445 if (tries2 && tries_so_far < tries) { 446 if (!IS_RATE_DEFINED(sn, rix2)) 447 return; 448 tt += calc_usecs_unicast_packet(sc, size, rix2, short_tries, 449 MIN(tries2 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 450 tries_so_far += tries2; 451 } 452 453 if (tries3 && tries_so_far < tries) { 454 if (!IS_RATE_DEFINED(sn, rix3)) 455 return; 456 tt += calc_usecs_unicast_packet(sc, size, rix3, short_tries, 457 MIN(tries3 + tries_so_far, tries) - tries_so_far - 1, is_ht40); 458 } 459 460 if (sn->stats[size_bin][rix0].total_packets < ssc->smoothing_minpackets) { 461 /* just average the first few packets */ 462 int avg_tx = sn->stats[size_bin][rix0].average_tx_time; 463 int packets = sn->stats[size_bin][rix0].total_packets; 464 sn->stats[size_bin][rix0].average_tx_time = (tt+(avg_tx*packets))/(packets+1); 465 } else { 466 /* use a ewma */ 467 sn->stats[size_bin][rix0].average_tx_time = 468 ((sn->stats[size_bin][rix0].average_tx_time * ssc->smoothing_rate) + 469 (tt * (100 - ssc->smoothing_rate))) / 100; 470 } 471 472 if (status != 0) { 473 int y; 474 sn->stats[size_bin][rix0].successive_failures++; 475 for (y = size_bin+1; y < NUM_PACKET_SIZE_BINS; y++) { 476 /* 477 * Also say larger packets failed since we 478 * assume if a small packet fails at a 479 * bit-rate then a larger one will also. 480 */ 481 sn->stats[y][rix0].successive_failures++; 482 sn->stats[y][rix0].last_tx = ticks; 483 sn->stats[y][rix0].tries += tries; 484 sn->stats[y][rix0].total_packets++; 485 } 486 } else { 487 sn->stats[size_bin][rix0].packets_acked++; 488 sn->stats[size_bin][rix0].successive_failures = 0; 489 } 490 sn->stats[size_bin][rix0].tries += tries; 491 sn->stats[size_bin][rix0].last_tx = ticks; 492 sn->stats[size_bin][rix0].total_packets++; 493 494 if (rix0 == sn->current_sample_rix[size_bin]) { 495 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 496 &an->an_node, 497 "%s: size %d %s sample rate %d tries (%d/%d) tt %d avg_tt (%d/%d)", 498 __func__, 499 size, 500 status ? "FAIL" : "OK", 501 rix0, short_tries, tries, tt, 502 sn->stats[size_bin][rix0].average_tx_time, 503 sn->stats[size_bin][rix0].perfect_tx_time); 504 sn->sample_tt[size_bin] = tt; 505 sn->current_sample_rix[size_bin] = -1; 506 } 507 } 508 509 static void 510 badrate(struct ifnet *ifp, int series, int hwrate, int tries, int status) 511 { 512 if_printf(ifp, "bad series%d hwrate 0x%x, tries %u ts_status 0x%x\n", 513 series, hwrate, tries, status); 514 } 515 516 void 517 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 518 const struct ath_buf *bf) 519 { 520 struct ifnet *ifp = sc->sc_ifp; 521 struct ieee80211com *ic = ifp->if_l2com; 522 struct sample_node *sn = ATH_NODE_SAMPLE(an); 523 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat; 524 const struct ath_desc *ds0 = &bf->bf_desc[0]; 525 int final_rix, short_tries, long_tries, frame_size; 526 const HAL_RATE_TABLE *rt = sc->sc_currates; 527 int mrr; 528 529 final_rix = rt->rateCodeToIndex[ts->ts_rate]; 530 short_tries = ts->ts_shortretry; 531 long_tries = ts->ts_longretry + 1; 532 frame_size = ds0->ds_ctl0 & 0x0fff; /* low-order 12 bits of ds_ctl0 */ 533 if (frame_size == 0) /* NB: should not happen */ 534 frame_size = 1500; 535 536 if (sn->ratemask == 0) { 537 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 538 &an->an_node, 539 "%s: size %d %s rate/try %d/%d no rates yet", 540 __func__, 541 bin_to_size(size_to_bin(frame_size)), 542 ts->ts_status ? "FAIL" : "OK", 543 short_tries, long_tries); 544 return; 545 } 546 mrr = sc->sc_mrretry && !(ic->ic_flags & IEEE80211_F_USEPROT); 547 if (!mrr || ts->ts_finaltsi == 0) { 548 if (!IS_RATE_DEFINED(sn, final_rix)) { 549 badrate(ifp, 0, ts->ts_rate, long_tries, ts->ts_status); 550 return; 551 } 552 /* 553 * Only one rate was used; optimize work. 554 */ 555 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 556 &an->an_node, "%s: size %d %s rate/try %d/%d/%d", 557 __func__, 558 bin_to_size(size_to_bin(frame_size)), 559 ts->ts_status ? "FAIL" : "OK", 560 dot11rate(rt, final_rix), short_tries, long_tries); 561 update_stats(sc, an, frame_size, 562 final_rix, long_tries, 563 0, 0, 564 0, 0, 565 0, 0, 566 short_tries, long_tries, ts->ts_status); 567 } else { 568 int hwrates[4], tries[4], rix[4]; 569 int finalTSIdx = ts->ts_finaltsi; 570 int i; 571 572 /* 573 * Process intermediate rates that failed. 574 */ 575 ath_hal_gettxcompletionrates(sc->sc_ah, ds0, hwrates, tries); 576 577 for (i = 0; i < 4; i++) { 578 rix[i] = rt->rateCodeToIndex[hwrates[i]]; 579 } 580 581 IEEE80211_NOTE(an->an_node.ni_vap, IEEE80211_MSG_RATECTL, 582 &an->an_node, 583 "%s: size %d finaltsidx %d tries %d %s rate/try [%d/%d %d/%d %d/%d %d/%d]", 584 __func__, 585 bin_to_size(size_to_bin(frame_size)), 586 finalTSIdx, 587 long_tries, 588 ts->ts_status ? "FAIL" : "OK", 589 dot11rate(rt, rix[0]), tries[0], 590 dot11rate(rt, rix[1]), tries[1], 591 dot11rate(rt, rix[2]), tries[2], 592 dot11rate(rt, rix[3]), tries[3]); 593 594 for (i = 0; i < 4; i++) { 595 if (tries[i] && !IS_RATE_DEFINED(sn, rix[i])) 596 badrate(ifp, 0, hwrates[i], tries[i], ts->ts_status); 597 } 598 599 /* 600 * NB: series > 0 are not penalized for failure 601 * based on the try counts under the assumption 602 * that losses are often bursty and since we 603 * sample higher rates 1 try at a time doing so 604 * may unfairly penalize them. 605 */ 606 if (tries[0]) { 607 update_stats(sc, an, frame_size, 608 rix[0], tries[0], 609 rix[1], tries[1], 610 rix[2], tries[2], 611 rix[3], tries[3], 612 short_tries, long_tries, 613 long_tries > tries[0]); 614 long_tries -= tries[0]; 615 } 616 617 if (tries[1] && finalTSIdx > 0) { 618 update_stats(sc, an, frame_size, 619 rix[1], tries[1], 620 rix[2], tries[2], 621 rix[3], tries[3], 622 0, 0, 623 short_tries, long_tries, 624 ts->ts_status); 625 long_tries -= tries[1]; 626 } 627 628 if (tries[2] && finalTSIdx > 1) { 629 update_stats(sc, an, frame_size, 630 rix[2], tries[2], 631 rix[3], tries[3], 632 0, 0, 633 0, 0, 634 short_tries, long_tries, 635 ts->ts_status); 636 long_tries -= tries[2]; 637 } 638 639 if (tries[3] && finalTSIdx > 2) { 640 update_stats(sc, an, frame_size, 641 rix[3], tries[3], 642 0, 0, 643 0, 0, 644 0, 0, 645 short_tries, long_tries, 646 ts->ts_status); 647 } 648 } 649 } 650 651 void 652 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 653 { 654 if (isnew) 655 ath_rate_ctl_reset(sc, &an->an_node); 656 } 657 658 static const struct txschedule *mrr_schedules[IEEE80211_MODE_MAX+2] = { 659 NULL, /* IEEE80211_MODE_AUTO */ 660 series_11a, /* IEEE80211_MODE_11A */ 661 series_11g, /* IEEE80211_MODE_11B */ 662 series_11g, /* IEEE80211_MODE_11G */ 663 NULL, /* IEEE80211_MODE_FH */ 664 series_11a, /* IEEE80211_MODE_TURBO_A */ 665 series_11g, /* IEEE80211_MODE_TURBO_G */ 666 series_11a, /* IEEE80211_MODE_STURBO_A */ 667 series_11na, /* IEEE80211_MODE_11NA */ 668 series_11ng, /* IEEE80211_MODE_11NG */ 669 series_half, /* IEEE80211_MODE_HALF */ 670 series_quarter, /* IEEE80211_MODE_QUARTER */ 671 }; 672 673 /* 674 * Initialize the tables for a node. 675 */ 676 static void 677 ath_rate_ctl_reset(struct ath_softc *sc, struct ieee80211_node *ni) 678 { 679 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 680 #define DOT11RATE(_ix) (rt->info[(_ix)].dot11Rate & IEEE80211_RATE_VAL) 681 #define MCS(_ix) (ni->ni_htrates.rs_rates[_ix] | IEEE80211_RATE_MCS) 682 683 struct ath_node *an = ATH_NODE(ni); 684 const struct ieee80211_txparam *tp = ni->ni_txparms; 685 struct sample_node *sn = ATH_NODE_SAMPLE(an); 686 const HAL_RATE_TABLE *rt = sc->sc_currates; 687 int x, y, srate, rix; 688 689 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 690 691 KASSERT(sc->sc_curmode < IEEE80211_MODE_MAX+2, 692 ("curmode %u", sc->sc_curmode)); 693 sn->sched = mrr_schedules[sc->sc_curmode]; 694 KASSERT(sn->sched != NULL, 695 ("no mrr schedule for mode %u", sc->sc_curmode)); 696 697 sn->static_rix = -1; 698 if (tp != NULL && tp->ucastrate != IEEE80211_FIXED_RATE_NONE) { 699 /* 700 * A fixed rate is to be used; ucastrate is the IEEE code 701 * for this rate (sans basic bit). Check this against the 702 * negotiated rate set for the node. Note the fixed rate 703 * may not be available for various reasons so we only 704 * setup the static rate index if the lookup is successful. 705 */ 706 707 /* XXX todo: check MCS rates */ 708 709 /* Check legacy rates */ 710 for (srate = ni->ni_rates.rs_nrates - 1; srate >= 0; srate--) 711 if (RATE(srate) == tp->ucastrate) { 712 sn->static_rix = sc->sc_rixmap[tp->ucastrate]; 713 break; 714 } 715 #ifdef IEEE80211_DEBUG 716 if (sn->static_rix == -1) { 717 IEEE80211_NOTE(ni->ni_vap, 718 IEEE80211_MSG_RATECTL, ni, 719 "%s: ucastrate %u not found, nrates %u", 720 __func__, tp->ucastrate, 721 ni->ni_rates.rs_nrates); 722 } 723 #endif 724 } 725 726 /* 727 * Construct a bitmask of usable rates. This has all 728 * negotiated rates minus those marked by the hal as 729 * to be ignored for doing rate control. 730 */ 731 sn->ratemask = 0; 732 /* MCS rates */ 733 if (ni->ni_flags & IEEE80211_NODE_HT) { 734 for (x = 0; x < ni->ni_htrates.rs_nrates; x++) { 735 rix = sc->sc_rixmap[MCS(x)]; 736 if (rix == 0xff) 737 continue; 738 /* skip rates marked broken by hal */ 739 if (!rt->info[rix].valid) 740 continue; 741 KASSERT(rix < SAMPLE_MAXRATES, 742 ("mcs %u has rix %d", MCS(x), rix)); 743 sn->ratemask |= 1<<rix; 744 } 745 } 746 747 /* Legacy rates */ 748 for (x = 0; x < ni->ni_rates.rs_nrates; x++) { 749 rix = sc->sc_rixmap[RATE(x)]; 750 if (rix == 0xff) 751 continue; 752 /* skip rates marked broken by hal */ 753 if (!rt->info[rix].valid) 754 continue; 755 KASSERT(rix < SAMPLE_MAXRATES, 756 ("rate %u has rix %d", RATE(x), rix)); 757 sn->ratemask |= 1<<rix; 758 } 759 #ifdef IEEE80211_DEBUG 760 if (ieee80211_msg(ni->ni_vap, IEEE80211_MSG_RATECTL)) { 761 uint32_t mask; 762 763 ieee80211_note(ni->ni_vap, "[%6D] %s: size 1600 rate/tt", 764 ni->ni_macaddr, ":", __func__); 765 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 766 if ((mask & 1) == 0) 767 continue; 768 printf(" %d/%d", dot11rate(rt, rix), 769 calc_usecs_unicast_packet(sc, 1600, rix, 0,0, 770 (ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40))); 771 } 772 printf("\n"); 773 } 774 #endif 775 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 776 int size = bin_to_size(y); 777 uint32_t mask; 778 779 sn->packets_sent[y] = 0; 780 sn->current_sample_rix[y] = -1; 781 sn->last_sample_rix[y] = 0; 782 /* XXX start with first valid rate */ 783 sn->current_rix[y] = ffs(sn->ratemask)-1; 784 785 /* 786 * Initialize the statistics buckets; these are 787 * indexed by the rate code index. 788 */ 789 for (rix = 0, mask = sn->ratemask; mask != 0; rix++, mask >>= 1) { 790 if ((mask & 1) == 0) /* not a valid rate */ 791 continue; 792 sn->stats[y][rix].successive_failures = 0; 793 sn->stats[y][rix].tries = 0; 794 sn->stats[y][rix].total_packets = 0; 795 sn->stats[y][rix].packets_acked = 0; 796 sn->stats[y][rix].last_tx = 0; 797 798 sn->stats[y][rix].perfect_tx_time = 799 calc_usecs_unicast_packet(sc, size, rix, 0, 0, 800 (ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40)); 801 sn->stats[y][rix].average_tx_time = 802 sn->stats[y][rix].perfect_tx_time; 803 } 804 } 805 #if 0 806 /* XXX 0, num_rates-1 are wrong */ 807 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 808 "%s: %d rates %d%sMbps (%dus)- %d%sMbps (%dus)", __func__, 809 sn->num_rates, 810 DOT11RATE(0)/2, DOT11RATE(0) % 1 ? ".5" : "", 811 sn->stats[1][0].perfect_tx_time, 812 DOT11RATE(sn->num_rates-1)/2, DOT11RATE(sn->num_rates-1) % 1 ? ".5" : "", 813 sn->stats[1][sn->num_rates-1].perfect_tx_time 814 ); 815 #endif 816 /* set the visible bit-rate */ 817 if (sn->static_rix != -1) 818 ni->ni_txrate = DOT11RATE(sn->static_rix); 819 else 820 ni->ni_txrate = RATE(0); 821 #undef RATE 822 #undef DOT11RATE 823 } 824 825 static void 826 sample_stats(void *arg, struct ieee80211_node *ni) 827 { 828 struct ath_softc *sc = arg; 829 const HAL_RATE_TABLE *rt = sc->sc_currates; 830 struct sample_node *sn = ATH_NODE_SAMPLE(ATH_NODE(ni)); 831 uint32_t mask; 832 int rix, y; 833 834 printf("\n[%s] refcnt %d static_rix %d ratemask 0x%x\n", 835 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni), 836 sn->static_rix, sn->ratemask); 837 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 838 printf("[%4u] cur rix %d since switch: packets %d ticks %u\n", 839 bin_to_size(y), sn->current_rix[y], 840 sn->packets_since_switch[y], sn->ticks_since_switch[y]); 841 printf("[%4u] last sample %d cur sample %d packets sent %d\n", 842 bin_to_size(y), sn->last_sample_rix[y], 843 sn->current_sample_rix[y], sn->packets_sent[y]); 844 printf("[%4u] packets since sample %d sample tt %u\n", 845 bin_to_size(y), sn->packets_since_sample[y], 846 sn->sample_tt[y]); 847 } 848 for (mask = sn->ratemask, rix = 0; mask != 0; mask >>= 1, rix++) { 849 if ((mask & 1) == 0) 850 continue; 851 for (y = 0; y < NUM_PACKET_SIZE_BINS; y++) { 852 if (sn->stats[y][rix].total_packets == 0) 853 continue; 854 printf("[%2u:%4u] %8d:%-8d (%3d%%) T %8d F %4d avg %5u last %u\n", 855 dot11rate(rt, rix), 856 bin_to_size(y), 857 sn->stats[y][rix].total_packets, 858 sn->stats[y][rix].packets_acked, 859 (100*sn->stats[y][rix].packets_acked)/sn->stats[y][rix].total_packets, 860 sn->stats[y][rix].tries, 861 sn->stats[y][rix].successive_failures, 862 sn->stats[y][rix].average_tx_time, 863 ticks - sn->stats[y][rix].last_tx); 864 } 865 } 866 } 867 868 static int 869 ath_rate_sysctl_stats(SYSCTL_HANDLER_ARGS) 870 { 871 struct ath_softc *sc = arg1; 872 struct ifnet *ifp = sc->sc_ifp; 873 struct ieee80211com *ic = ifp->if_l2com; 874 int error, v; 875 876 v = 0; 877 error = sysctl_handle_int(oidp, &v, 0, req); 878 if (error || !req->newptr) 879 return error; 880 ieee80211_iterate_nodes(&ic->ic_sta, sample_stats, sc); 881 return 0; 882 } 883 884 static int 885 ath_rate_sysctl_smoothing_rate(SYSCTL_HANDLER_ARGS) 886 { 887 struct sample_softc *ssc = arg1; 888 int rate, error; 889 890 rate = ssc->smoothing_rate; 891 error = sysctl_handle_int(oidp, &rate, 0, req); 892 if (error || !req->newptr) 893 return error; 894 if (!(0 <= rate && rate < 100)) 895 return EINVAL; 896 ssc->smoothing_rate = rate; 897 ssc->smoothing_minpackets = 100 / (100 - rate); 898 return 0; 899 } 900 901 static int 902 ath_rate_sysctl_sample_rate(SYSCTL_HANDLER_ARGS) 903 { 904 struct sample_softc *ssc = arg1; 905 int rate, error; 906 907 rate = ssc->sample_rate; 908 error = sysctl_handle_int(oidp, &rate, 0, req); 909 if (error || !req->newptr) 910 return error; 911 if (!(2 <= rate && rate <= 100)) 912 return EINVAL; 913 ssc->sample_rate = rate; 914 return 0; 915 } 916 917 static void 918 ath_rate_sysctlattach(struct ath_softc *sc, struct sample_softc *ssc) 919 { 920 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 921 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 922 923 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 924 "smoothing_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 925 ath_rate_sysctl_smoothing_rate, "I", 926 "sample: smoothing rate for avg tx time (%%)"); 927 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 928 "sample_rate", CTLTYPE_INT | CTLFLAG_RW, ssc, 0, 929 ath_rate_sysctl_sample_rate, "I", 930 "sample: percent air time devoted to sampling new rates (%%)"); 931 /* XXX max_successive_failures, stale_failure_timeout, min_switch */ 932 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 933 "sample_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0, 934 ath_rate_sysctl_stats, "I", "sample: print statistics"); 935 } 936 937 struct ath_ratectrl * 938 ath_rate_attach(struct ath_softc *sc) 939 { 940 struct sample_softc *ssc; 941 942 ssc = malloc(sizeof(struct sample_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 943 if (ssc == NULL) 944 return NULL; 945 ssc->arc.arc_space = sizeof(struct sample_node); 946 ssc->smoothing_rate = 95; /* ewma percentage ([0..99]) */ 947 ssc->smoothing_minpackets = 100 / (100 - ssc->smoothing_rate); 948 ssc->sample_rate = 10; /* %time to try diff tx rates */ 949 ssc->max_successive_failures = 3; /* threshold for rate sampling*/ 950 ssc->stale_failure_timeout = 10 * hz; /* 10 seconds */ 951 ssc->min_switch = hz; /* 1 second */ 952 ath_rate_sysctlattach(sc, ssc); 953 return &ssc->arc; 954 } 955 956 void 957 ath_rate_detach(struct ath_ratectrl *arc) 958 { 959 struct sample_softc *ssc = (struct sample_softc *) arc; 960 961 free(ssc, M_DEVBUF); 962 } 963