1 /*- 2 * Copyright (c) 2004 INRIA 3 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting 4 * 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 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer, 11 * without modification. 12 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 13 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 14 * redistribution must be conditioned upon including a substantially 15 * similar Disclaimer requirement for further binary redistribution. 16 * 3. Neither the names of the above-listed copyright holders nor the names 17 * of any contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * Alternatively, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") version 2 as published by the Free 22 * Software Foundation. 23 * 24 * NO WARRANTY 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 27 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 28 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 29 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 30 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 33 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 35 * THE POSSIBILITY OF SUCH DAMAGES. 36 * 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 /* 43 * AMRR rate control. See: 44 * http://www-sop.inria.fr/rapports/sophia/RR-5208.html 45 * "IEEE 802.11 Rate Adaptation: A Practical Approach" by 46 * Mathieu Lacage, Hossein Manshaei, Thierry Turletti 47 */ 48 #include "opt_inet.h" 49 50 #include <sys/param.h> 51 #include <sys/systm.h> 52 #include <sys/sysctl.h> 53 #include <sys/module.h> 54 #include <sys/kernel.h> 55 #include <sys/lock.h> 56 #include <sys/mutex.h> 57 #include <sys/errno.h> 58 59 #include <machine/bus.h> 60 #include <machine/resource.h> 61 #include <sys/bus.h> 62 63 #include <sys/socket.h> 64 65 #include <net/if.h> 66 #include <net/if_media.h> 67 #include <net/if_arp.h> 68 #include <net/ethernet.h> /* XXX for ether_sprintf */ 69 70 #include <net80211/ieee80211_var.h> 71 72 #include <net/bpf.h> 73 74 #ifdef INET 75 #include <netinet/in.h> 76 #include <netinet/if_ether.h> 77 #endif 78 79 #include <dev/ath/if_athvar.h> 80 #include <dev/ath/ath_rate/amrr/amrr.h> 81 #include <contrib/dev/ath/ah_desc.h> 82 83 #define AMRR_DEBUG 84 #ifdef AMRR_DEBUG 85 #define DPRINTF(sc, _fmt, ...) do { \ 86 if (sc->sc_debug & 0x10) \ 87 printf(_fmt, __VA_ARGS__); \ 88 } while (0) 89 #else 90 #define DPRINTF(sc, _fmt, ...) 91 #endif 92 93 static int ath_rateinterval = 1000; /* rate ctl interval (ms) */ 94 static int ath_rate_max_success_threshold = 10; 95 static int ath_rate_min_success_threshold = 1; 96 97 static void ath_ratectl(void *); 98 static void ath_rate_update(struct ath_softc *, struct ieee80211_node *, 99 int rate); 100 static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *); 101 static void ath_rate_ctl(void *, struct ieee80211_node *); 102 103 void 104 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 105 { 106 /* NB: assumed to be zero'd by caller */ 107 ath_rate_update(sc, &an->an_node, 0); 108 } 109 110 void 111 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 112 { 113 } 114 115 void 116 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 117 HAL_BOOL shortPreamble, size_t frameLen, 118 u_int8_t *rix, int *try0, u_int8_t *txrate) 119 { 120 struct amrr_node *amn = ATH_NODE_AMRR(an); 121 122 *rix = amn->amn_tx_rix0; 123 *try0 = amn->amn_tx_try0; 124 if (shortPreamble) 125 *txrate = amn->amn_tx_rate0sp; 126 else 127 *txrate = amn->amn_tx_rate0; 128 } 129 130 void 131 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 132 struct ath_desc *ds, HAL_BOOL shortPreamble, u_int8_t rix) 133 { 134 struct amrr_node *amn = ATH_NODE_AMRR(an); 135 136 ath_hal_setupxtxdesc(sc->sc_ah, ds 137 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */ 138 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */ 139 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */ 140 ); 141 } 142 143 void 144 ath_rate_tx_complete(struct ath_softc *sc, 145 struct ath_node *an, const struct ath_desc *ds) 146 { 147 struct amrr_node *amn = ATH_NODE_AMRR(an); 148 int sr = ds->ds_txstat.ts_shortretry; 149 int lr = ds->ds_txstat.ts_longretry; 150 int retry_count = sr + lr; 151 152 amn->amn_tx_try0_cnt++; 153 if (retry_count == 1) { 154 amn->amn_tx_try1_cnt++; 155 } else if (retry_count == 2) { 156 amn->amn_tx_try1_cnt++; 157 amn->amn_tx_try2_cnt++; 158 } else if (retry_count == 3) { 159 amn->amn_tx_try1_cnt++; 160 amn->amn_tx_try2_cnt++; 161 amn->amn_tx_try3_cnt++; 162 } else if (retry_count > 3) { 163 amn->amn_tx_try1_cnt++; 164 amn->amn_tx_try2_cnt++; 165 amn->amn_tx_try3_cnt++; 166 amn->amn_tx_failure_cnt++; 167 } 168 } 169 170 void 171 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 172 { 173 if (isnew) 174 ath_rate_ctl_start(sc, &an->an_node); 175 } 176 177 static void 178 node_reset (struct amrr_node *amn) 179 { 180 amn->amn_tx_try0_cnt = 0; 181 amn->amn_tx_try1_cnt = 0; 182 amn->amn_tx_try2_cnt = 0; 183 amn->amn_tx_try3_cnt = 0; 184 amn->amn_tx_failure_cnt = 0; 185 amn->amn_success = 0; 186 amn->amn_recovery = 0; 187 amn->amn_success_threshold = ath_rate_min_success_threshold; 188 } 189 190 191 /** 192 * The code below assumes that we are dealing with hardware multi rate retry 193 * I have no idea what will happen if you try to use this module with another 194 * type of hardware. Your machine might catch fire or it might work with 195 * horrible performance... 196 */ 197 static void 198 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 199 { 200 struct ath_node *an = ATH_NODE(ni); 201 struct amrr_node *amn = ATH_NODE_AMRR(an); 202 const HAL_RATE_TABLE *rt = sc->sc_currates; 203 u_int8_t rix; 204 205 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 206 207 DPRINTF(sc, "%s: set xmit rate for %s to %dM\n", 208 __func__, ether_sprintf(ni->ni_macaddr), 209 ni->ni_rates.rs_nrates > 0 ? 210 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 211 212 ni->ni_txrate = rate; 213 /* XXX management/control frames always go at the lowest speed */ 214 an->an_tx_mgtrate = rt->info[0].rateCode; 215 an->an_tx_mgtratesp = an->an_tx_mgtrate | rt->info[0].shortPreamble; 216 /* 217 * Before associating a node has no rate set setup 218 * so we can't calculate any transmit codes to use. 219 * This is ok since we should never be sending anything 220 * but management frames and those always go at the 221 * lowest hardware rate. 222 */ 223 if (ni->ni_rates.rs_nrates > 0) { 224 amn->amn_tx_rix0 = sc->sc_rixmap[ 225 ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL]; 226 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode; 227 amn->amn_tx_rate0sp = amn->amn_tx_rate0 | 228 rt->info[amn->amn_tx_rix0].shortPreamble; 229 if (sc->sc_mrretry) { 230 amn->amn_tx_try0 = 1; 231 amn->amn_tx_try1 = 1; 232 amn->amn_tx_try2 = 1; 233 amn->amn_tx_try3 = 1; 234 if (--rate >= 0) { 235 rix = sc->sc_rixmap[ 236 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 237 amn->amn_tx_rate1 = rt->info[rix].rateCode; 238 amn->amn_tx_rate1sp = amn->amn_tx_rate1 | 239 rt->info[rix].shortPreamble; 240 } else { 241 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 242 } 243 if (--rate >= 0) { 244 rix = sc->sc_rixmap[ 245 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 246 amn->amn_tx_rate2 = rt->info[rix].rateCode; 247 amn->amn_tx_rate2sp = amn->amn_tx_rate2 | 248 rt->info[rix].shortPreamble; 249 } else { 250 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 251 } 252 if (rate > 0) { 253 /* NB: only do this if we didn't already do it above */ 254 amn->amn_tx_rate3 = rt->info[0].rateCode; 255 amn->amn_tx_rate3sp = 256 an->an_tx_mgtrate | rt->info[0].shortPreamble; 257 } else { 258 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 259 } 260 } else { 261 amn->amn_tx_try0 = ATH_TXMAXTRY; 262 /* theorically, these statements are useless because 263 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY 264 */ 265 amn->amn_tx_try1 = 0; 266 amn->amn_tx_try2 = 0; 267 amn->amn_tx_try3 = 0; 268 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 269 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 270 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 271 } 272 } 273 node_reset (amn); 274 } 275 276 /* 277 * Set the starting transmit rate for a node. 278 */ 279 static void 280 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 281 { 282 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 283 struct ieee80211com *ic = &sc->sc_ic; 284 int srate; 285 286 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 287 if (ic->ic_fixed_rate == -1) { 288 /* 289 * No fixed rate is requested. For 11b start with 290 * the highest negotiated rate; otherwise, for 11g 291 * and 11a, we start "in the middle" at 24Mb or 36Mb. 292 */ 293 srate = ni->ni_rates.rs_nrates - 1; 294 if (sc->sc_curmode != IEEE80211_MODE_11B) { 295 /* 296 * Scan the negotiated rate set to find the 297 * closest rate. 298 */ 299 /* NB: the rate set is assumed sorted */ 300 for (; srate >= 0 && RATE(srate) > 72; srate--) 301 ; 302 KASSERT(srate >= 0, ("bogus rate set")); 303 } 304 } else { 305 /* 306 * A fixed rate is to be used; ic_fixed_rate is an 307 * index into the supported rate set. Convert this 308 * to the index into the negotiated rate set for 309 * the node. We know the rate is there because the 310 * rate set is checked when the station associates. 311 */ 312 const struct ieee80211_rateset *rs = 313 &ic->ic_sup_rates[ic->ic_curmode]; 314 int r = rs->rs_rates[ic->ic_fixed_rate] & IEEE80211_RATE_VAL; 315 /* NB: the rate set is assumed sorted */ 316 srate = ni->ni_rates.rs_nrates - 1; 317 for (; srate >= 0 && RATE(srate) != r; srate--) 318 ; 319 KASSERT(srate >= 0, 320 ("fixed rate %d not in rate set", ic->ic_fixed_rate)); 321 } 322 ath_rate_update(sc, ni, srate); 323 #undef RATE 324 } 325 326 static void 327 ath_rate_cb(void *arg, struct ieee80211_node *ni) 328 { 329 ath_rate_update(ni->ni_ic->ic_ifp->if_softc, ni, (int)(uintptr_t) arg); 330 } 331 332 /* 333 * Reset the rate control state for each 802.11 state transition. 334 */ 335 void 336 ath_rate_newstate(struct ath_softc *sc, enum ieee80211_state state) 337 { 338 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; 339 struct ieee80211com *ic = &sc->sc_ic; 340 struct ieee80211_node *ni; 341 342 if (state == IEEE80211_S_INIT) { 343 callout_stop(&asc->timer); 344 return; 345 } 346 if (ic->ic_opmode == IEEE80211_M_STA) { 347 /* 348 * Reset local xmit state; this is really only 349 * meaningful when operating in station mode. 350 */ 351 ni = ic->ic_bss; 352 if (state == IEEE80211_S_RUN) { 353 ath_rate_ctl_start(sc, ni); 354 } else { 355 ath_rate_update(sc, ni, 0); 356 } 357 } else { 358 /* 359 * When operating as a station the node table holds 360 * the AP's that were discovered during scanning. 361 * For any other operating mode we want to reset the 362 * tx rate state of each node. 363 */ 364 ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_cb, 0); 365 ath_rate_update(sc, ic->ic_bss, 0); 366 } 367 if (ic->ic_fixed_rate == -1 && state == IEEE80211_S_RUN) { 368 int interval; 369 /* 370 * Start the background rate control thread if we 371 * are not configured to use a fixed xmit rate. 372 */ 373 interval = ath_rateinterval; 374 if (ic->ic_opmode == IEEE80211_M_STA) 375 interval /= 2; 376 callout_reset(&asc->timer, (interval * hz) / 1000, 377 ath_ratectl, &sc->sc_if); 378 } 379 } 380 381 /* 382 * Examine and potentially adjust the transmit rate. 383 */ 384 static void 385 ath_rate_ctl(void *arg, struct ieee80211_node *ni) 386 { 387 struct ath_softc *sc = arg; 388 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni)); 389 int old_rate; 390 391 #define is_success(amn) \ 392 (amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10)) 393 #define is_enough(amn) \ 394 (amn->amn_tx_try0_cnt > 10) 395 #define is_failure(amn) \ 396 (amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3)) 397 #define is_max_rate(ni) \ 398 ((ni->ni_txrate + 1) >= ni->ni_rates.rs_nrates) 399 #define is_min_rate(ni) \ 400 (ni->ni_txrate == 0) 401 402 old_rate = ni->ni_txrate; 403 404 DPRINTF (sc, "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d\n", 405 amn->amn_tx_try0_cnt, 406 amn->amn_tx_try1_cnt, 407 amn->amn_tx_try2_cnt, 408 amn->amn_tx_try3_cnt, 409 amn->amn_success_threshold); 410 if (is_success (amn) && is_enough (amn)) { 411 amn->amn_success++; 412 if (amn->amn_success == amn->amn_success_threshold && 413 !is_max_rate (ni)) { 414 amn->amn_recovery = 1; 415 amn->amn_success = 0; 416 ni->ni_txrate++; 417 DPRINTF (sc, "increase rate to %d\n", ni->ni_txrate); 418 } else { 419 amn->amn_recovery = 0; 420 } 421 } else if (is_failure (amn)) { 422 amn->amn_success = 0; 423 if (!is_min_rate (ni)) { 424 if (amn->amn_recovery) { 425 /* recovery failure. */ 426 amn->amn_success_threshold *= 2; 427 amn->amn_success_threshold = min (amn->amn_success_threshold, 428 (u_int)ath_rate_max_success_threshold); 429 DPRINTF (sc, "decrease rate recovery thr: %d\n", amn->amn_success_threshold); 430 } else { 431 /* simple failure. */ 432 amn->amn_success_threshold = ath_rate_min_success_threshold; 433 DPRINTF (sc, "decrease rate normal thr: %d\n", amn->amn_success_threshold); 434 } 435 amn->amn_recovery = 0; 436 ni->ni_txrate--; 437 } else { 438 amn->amn_recovery = 0; 439 } 440 441 } 442 if (is_enough (amn) || old_rate != ni->ni_txrate) { 443 /* reset counters. */ 444 amn->amn_tx_try0_cnt = 0; 445 amn->amn_tx_try1_cnt = 0; 446 amn->amn_tx_try2_cnt = 0; 447 amn->amn_tx_try3_cnt = 0; 448 amn->amn_tx_failure_cnt = 0; 449 } 450 if (old_rate != ni->ni_txrate) { 451 ath_rate_update(sc, ni, ni->ni_txrate); 452 } 453 } 454 455 static void 456 ath_ratectl(void *arg) 457 { 458 struct ifnet *ifp = arg; 459 struct ath_softc *sc = ifp->if_softc; 460 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; 461 struct ieee80211com *ic = &sc->sc_ic; 462 int interval; 463 464 if (ifp->if_flags & IFF_RUNNING) { 465 sc->sc_stats.ast_rate_calls++; 466 467 if (ic->ic_opmode == IEEE80211_M_STA) 468 ath_rate_ctl(sc, ic->ic_bss); /* NB: no reference */ 469 else 470 ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_ctl, sc); 471 } 472 interval = ath_rateinterval; 473 if (ic->ic_opmode == IEEE80211_M_STA) 474 interval /= 2; 475 callout_reset(&asc->timer, (interval * hz) / 1000, 476 ath_ratectl, &sc->sc_if); 477 } 478 479 static void 480 ath_rate_sysctlattach(struct ath_softc *sc) 481 { 482 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 483 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 484 485 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 486 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 487 "rate control: operation interval (ms)"); 488 /* XXX bounds check values */ 489 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 490 "max_sucess_threshold", CTLFLAG_RW, 491 &ath_rate_max_success_threshold, 0, ""); 492 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 493 "min_sucess_threshold", CTLFLAG_RW, 494 &ath_rate_min_success_threshold, 0, ""); 495 } 496 497 struct ath_ratectrl * 498 ath_rate_attach(struct ath_softc *sc) 499 { 500 struct amrr_softc *asc; 501 502 asc = malloc(sizeof(struct amrr_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 503 if (asc == NULL) 504 return NULL; 505 asc->arc.arc_space = sizeof(struct amrr_node); 506 callout_init(&asc->timer, debug_mpsafenet ? CALLOUT_MPSAFE : 0); 507 ath_rate_sysctlattach(sc); 508 509 return &asc->arc; 510 } 511 512 void 513 ath_rate_detach(struct ath_ratectrl *arc) 514 { 515 struct amrr_softc *asc = (struct amrr_softc *) arc; 516 517 callout_drain(&asc->timer); 518 free(asc, M_DEVBUF); 519 } 520 521 /* 522 * Module glue. 523 */ 524 static int 525 amrr_modevent(module_t mod, int type, void *unused) 526 { 527 switch (type) { 528 case MOD_LOAD: 529 if (bootverbose) 530 printf("ath_rate: <AMRR rate control algorithm> version 0.1\n"); 531 return 0; 532 case MOD_UNLOAD: 533 return 0; 534 } 535 return EINVAL; 536 } 537 538 static moduledata_t amrr_mod = { 539 "ath_rate", 540 amrr_modevent, 541 0 542 }; 543 DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST); 544 MODULE_VERSION(ath_rate, 1); 545 MODULE_DEPEND(ath_rate, wlan, 1, 1, 1); 546