1 /* $NetBSD: athrate-amrr.c,v 1.10 2008/01/04 21:17:56 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 2004 INRIA 5 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer, 13 * without modification. 14 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 15 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 16 * redistribution must be conditioned upon including a substantially 17 * similar Disclaimer requirement for further binary redistribution. 18 * 3. Neither the names of the above-listed copyright holders nor the names 19 * of any contributors may be used to endorse or promote products derived 20 * from this software without specific prior written permission. 21 * 22 * Alternatively, this software may be distributed under the terms of the 23 * GNU General Public License ("GPL") version 2 as published by the Free 24 * Software Foundation. 25 * 26 * NO WARRANTY 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 29 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 30 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 31 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 32 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 35 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 37 * THE POSSIBILITY OF SUCH DAMAGES. 38 * 39 */ 40 41 #include <sys/cdefs.h> 42 #ifdef __FreeBSD__ 43 __FBSDID("$FreeBSD: src/sys/dev/ath/ath_rate/amrr/amrr.c,v 1.10 2005/08/09 10:19:43 rwatson Exp $"); 44 #endif 45 #ifdef __NetBSD__ 46 __KERNEL_RCSID(0, "$NetBSD: athrate-amrr.c,v 1.10 2008/01/04 21:17:56 ad Exp $"); 47 #endif 48 49 /* 50 * AMRR rate control. See: 51 * http://www-sop.inria.fr/rapports/sophia/RR-5208.html 52 * "IEEE 802.11 Rate Adaptation: A Practical Approach" by 53 * Mathieu Lacage, Hossein Manshaei, Thierry Turletti 54 */ 55 #include "opt_inet.h" 56 57 #include <sys/param.h> 58 #include <sys/systm.h> 59 #include <sys/sysctl.h> 60 #include <sys/kernel.h> 61 #include <sys/errno.h> 62 #include <sys/bus.h> 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/if_ether.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 #endif 77 78 #include <dev/ic/athvar.h> 79 #include <dev/ic/athrate-amrr.h> 80 #include <contrib/dev/ath/ah_desc.h> 81 82 #define AMRR_DEBUG 83 #ifdef AMRR_DEBUG 84 #define DPRINTF(sc, _fmt, ...) do { \ 85 if (sc->sc_debug & 0x10) \ 86 printf(_fmt, __VA_ARGS__); \ 87 } while (0) 88 #else 89 #define DPRINTF(sc, _fmt, ...) 90 #endif 91 92 static int ath_rateinterval = 1000; /* rate ctl interval (ms) */ 93 static int ath_rate_max_success_threshold = 10; 94 static int ath_rate_min_success_threshold = 1; 95 96 static void ath_ratectl(void *); 97 static void ath_rate_update(struct ath_softc *, struct ieee80211_node *, 98 int rate); 99 static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *); 100 static void ath_rate_ctl(void *, struct ieee80211_node *); 101 102 void 103 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 104 { 105 /* NB: assumed to be zero'd by caller */ 106 ath_rate_update(sc, &an->an_node, 0); 107 } 108 109 void 110 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 111 { 112 } 113 114 void 115 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 116 int shortPreamble, size_t frameLen, 117 u_int8_t *rix, int *try0, u_int8_t *txrate) 118 { 119 struct amrr_node *amn = ATH_NODE_AMRR(an); 120 121 *rix = amn->amn_tx_rix0; 122 *try0 = amn->amn_tx_try0; 123 if (shortPreamble) 124 *txrate = amn->amn_tx_rate0sp; 125 else 126 *txrate = amn->amn_tx_rate0; 127 } 128 129 void 130 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 131 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 132 { 133 struct amrr_node *amn = ATH_NODE_AMRR(an); 134 135 ath_hal_setupxtxdesc(sc->sc_ah, ds 136 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */ 137 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */ 138 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */ 139 ); 140 } 141 142 void 143 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 144 const struct ath_desc *ds, const struct ath_desc *ds0) 145 { 146 struct amrr_node *amn = ATH_NODE_AMRR(an); 147 int sr = ds->ds_txstat.ts_shortretry; 148 int lr = ds->ds_txstat.ts_longretry; 149 int retry_count = sr + lr; 150 151 amn->amn_tx_try0_cnt++; 152 if (retry_count == 1) { 153 amn->amn_tx_try1_cnt++; 154 } else if (retry_count == 2) { 155 amn->amn_tx_try1_cnt++; 156 amn->amn_tx_try2_cnt++; 157 } else if (retry_count == 3) { 158 amn->amn_tx_try1_cnt++; 159 amn->amn_tx_try2_cnt++; 160 amn->amn_tx_try3_cnt++; 161 } else if (retry_count > 3) { 162 amn->amn_tx_try1_cnt++; 163 amn->amn_tx_try2_cnt++; 164 amn->amn_tx_try3_cnt++; 165 amn->amn_tx_failure_cnt++; 166 } 167 } 168 169 void 170 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 171 { 172 if (isnew) 173 ath_rate_ctl_start(sc, &an->an_node); 174 } 175 176 static void 177 node_reset (struct amrr_node *amn) 178 { 179 amn->amn_tx_try0_cnt = 0; 180 amn->amn_tx_try1_cnt = 0; 181 amn->amn_tx_try2_cnt = 0; 182 amn->amn_tx_try3_cnt = 0; 183 amn->amn_tx_failure_cnt = 0; 184 amn->amn_success = 0; 185 amn->amn_recovery = 0; 186 amn->amn_success_threshold = ath_rate_min_success_threshold; 187 } 188 189 190 /** 191 * The code below assumes that we are dealing with hardware multi rate retry 192 * I have no idea what will happen if you try to use this module with another 193 * type of hardware. Your machine might catch fire or it might work with 194 * horrible performance... 195 */ 196 static void 197 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 198 { 199 struct ath_node *an = ATH_NODE(ni); 200 struct amrr_node *amn = ATH_NODE_AMRR(an); 201 const HAL_RATE_TABLE *rt = sc->sc_currates; 202 u_int8_t rix; 203 204 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 205 206 DPRINTF(sc, "%s: set xmit rate for %s to %dM\n", 207 __func__, ether_sprintf(ni->ni_macaddr), 208 ni->ni_rates.rs_nrates > 0 ? 209 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 210 211 ni->ni_txrate = rate; 212 /* 213 * Before associating a node has no rate set setup 214 * so we can't calculate any transmit codes to use. 215 * This is ok since we should never be sending anything 216 * but management frames and those always go at the 217 * lowest hardware rate. 218 */ 219 if (ni->ni_rates.rs_nrates > 0) { 220 amn->amn_tx_rix0 = sc->sc_rixmap[ 221 ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL]; 222 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode; 223 amn->amn_tx_rate0sp = amn->amn_tx_rate0 | 224 rt->info[amn->amn_tx_rix0].shortPreamble; 225 if (sc->sc_mrretry) { 226 amn->amn_tx_try0 = 1; 227 amn->amn_tx_try1 = 1; 228 amn->amn_tx_try2 = 1; 229 amn->amn_tx_try3 = 1; 230 if (--rate >= 0) { 231 rix = sc->sc_rixmap[ 232 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 233 amn->amn_tx_rate1 = rt->info[rix].rateCode; 234 amn->amn_tx_rate1sp = amn->amn_tx_rate1 | 235 rt->info[rix].shortPreamble; 236 } else { 237 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 238 } 239 if (--rate >= 0) { 240 rix = sc->sc_rixmap[ 241 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 242 amn->amn_tx_rate2 = rt->info[rix].rateCode; 243 amn->amn_tx_rate2sp = amn->amn_tx_rate2 | 244 rt->info[rix].shortPreamble; 245 } else { 246 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 247 } 248 if (rate > 0) { 249 /* NB: only do this if we didn't already do it above */ 250 amn->amn_tx_rate3 = rt->info[0].rateCode; 251 amn->amn_tx_rate3sp = 252 an->an_tx_rate3 | rt->info[0].shortPreamble; 253 } else { 254 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 255 } 256 } else { 257 amn->amn_tx_try0 = ATH_TXMAXTRY; 258 /* theorically, these statements are useless because 259 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY 260 */ 261 amn->amn_tx_try1 = 0; 262 amn->amn_tx_try2 = 0; 263 amn->amn_tx_try3 = 0; 264 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 265 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 266 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 267 } 268 } 269 node_reset (amn); 270 } 271 272 /* 273 * Set the starting transmit rate for a node. 274 */ 275 static void 276 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 277 { 278 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 279 struct ieee80211com *ic = &sc->sc_ic; 280 int srate; 281 282 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 283 if (ic->ic_fixed_rate == IEEE80211_FIXED_RATE_NONE) { 284 /* 285 * No fixed rate is requested. For 11b start with 286 * the highest negotiated rate; otherwise, for 11g 287 * and 11a, we start "in the middle" at 24Mb or 36Mb. 288 */ 289 srate = ni->ni_rates.rs_nrates - 1; 290 if (sc->sc_curmode != IEEE80211_MODE_11B) { 291 /* 292 * Scan the negotiated rate set to find the 293 * closest rate. 294 */ 295 /* NB: the rate set is assumed sorted */ 296 for (; srate >= 0 && RATE(srate) > 72; srate--) 297 ; 298 KASSERT(srate >= 0, ("bogus rate set")); 299 } 300 } else { 301 /* 302 * A fixed rate is to be used; ic_fixed_rate is an 303 * index into the supported rate set. Convert this 304 * to the index into the negotiated rate set for 305 * the node. We know the rate is there because the 306 * rate set is checked when the station associates. 307 */ 308 const struct ieee80211_rateset *rs = 309 &ic->ic_sup_rates[ic->ic_curmode]; 310 int r = rs->rs_rates[ic->ic_fixed_rate] & IEEE80211_RATE_VAL; 311 /* NB: the rate set is assumed sorted */ 312 srate = ni->ni_rates.rs_nrates - 1; 313 for (; srate >= 0 && RATE(srate) != r; srate--) 314 ; 315 KASSERT(srate >= 0, 316 ("fixed rate %d not in rate set", ic->ic_fixed_rate)); 317 } 318 ath_rate_update(sc, ni, srate); 319 #undef RATE 320 } 321 322 static void 323 ath_rate_cb(void *arg, struct ieee80211_node *ni) 324 { 325 struct ath_softc *sc = arg; 326 327 ath_rate_update(sc, ni, 0); 328 } 329 330 /* 331 * Reset the rate control state for each 802.11 state transition. 332 */ 333 void 334 ath_rate_newstate(struct ath_softc *sc, enum ieee80211_state state) 335 { 336 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; 337 struct ieee80211com *ic = &sc->sc_ic; 338 struct ieee80211_node *ni; 339 340 if (state == IEEE80211_S_INIT) { 341 callout_stop(&asc->timer); 342 return; 343 } 344 if (ic->ic_opmode == IEEE80211_M_STA) { 345 /* 346 * Reset local xmit state; this is really only 347 * meaningful when operating in station mode. 348 */ 349 ni = ic->ic_bss; 350 if (state == IEEE80211_S_RUN) { 351 ath_rate_ctl_start(sc, ni); 352 } else { 353 ath_rate_update(sc, ni, 0); 354 } 355 } else { 356 /* 357 * When operating as a station the node table holds 358 * the AP's that were discovered during scanning. 359 * For any other operating mode we want to reset the 360 * tx rate state of each node. 361 */ 362 ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_cb, sc); 363 ath_rate_update(sc, ic->ic_bss, 0); 364 } 365 if (ic->ic_fixed_rate == IEEE80211_FIXED_RATE_NONE && 366 state == IEEE80211_S_RUN) { 367 int interval; 368 /* 369 * Start the background rate control thread if we 370 * are not configured to use a fixed xmit rate. 371 */ 372 interval = ath_rateinterval; 373 if (ic->ic_opmode == IEEE80211_M_STA) 374 interval /= 2; 375 callout_reset(&asc->timer, (interval * hz) / 1000, 376 ath_ratectl, &sc->sc_if); 377 } 378 } 379 380 /* 381 * Examine and potentially adjust the transmit rate. 382 */ 383 static void 384 ath_rate_ctl(void *arg, struct ieee80211_node *ni) 385 { 386 struct ath_softc *sc = arg; 387 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni)); 388 int old_rate; 389 390 #define is_success(amn) \ 391 (amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10)) 392 #define is_enough(amn) \ 393 (amn->amn_tx_try0_cnt > 10) 394 #define is_failure(amn) \ 395 (amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3)) 396 #define is_max_rate(ni) \ 397 ((ni->ni_txrate + 1) >= ni->ni_rates.rs_nrates) 398 #define is_min_rate(ni) \ 399 (ni->ni_txrate == 0) 400 401 old_rate = ni->ni_txrate; 402 403 DPRINTF (sc, "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d\n", 404 amn->amn_tx_try0_cnt, 405 amn->amn_tx_try1_cnt, 406 amn->amn_tx_try2_cnt, 407 amn->amn_tx_try3_cnt, 408 amn->amn_success_threshold); 409 if (is_success (amn) && is_enough (amn)) { 410 amn->amn_success++; 411 if (amn->amn_success == amn->amn_success_threshold && 412 !is_max_rate (ni)) { 413 amn->amn_recovery = 1; 414 amn->amn_success = 0; 415 ni->ni_txrate++; 416 DPRINTF (sc, "increase rate to %d\n", ni->ni_txrate); 417 } else { 418 amn->amn_recovery = 0; 419 } 420 } else if (is_failure (amn)) { 421 amn->amn_success = 0; 422 if (!is_min_rate (ni)) { 423 if (amn->amn_recovery) { 424 /* recovery failure. */ 425 amn->amn_success_threshold *= 2; 426 amn->amn_success_threshold = min (amn->amn_success_threshold, 427 (u_int)ath_rate_max_success_threshold); 428 DPRINTF (sc, "decrease rate recovery thr: %d\n", amn->amn_success_threshold); 429 } else { 430 /* simple failure. */ 431 amn->amn_success_threshold = ath_rate_min_success_threshold; 432 DPRINTF (sc, "decrease rate normal thr: %d\n", amn->amn_success_threshold); 433 } 434 amn->amn_recovery = 0; 435 ni->ni_txrate--; 436 } else { 437 amn->amn_recovery = 0; 438 } 439 440 } 441 if (is_enough (amn) || old_rate != ni->ni_txrate) { 442 /* reset counters. */ 443 amn->amn_tx_try0_cnt = 0; 444 amn->amn_tx_try1_cnt = 0; 445 amn->amn_tx_try2_cnt = 0; 446 amn->amn_tx_try3_cnt = 0; 447 amn->amn_tx_failure_cnt = 0; 448 } 449 if (old_rate != ni->ni_txrate) { 450 ath_rate_update(sc, ni, ni->ni_txrate); 451 } 452 } 453 454 static void 455 ath_ratectl(void *arg) 456 { 457 struct ifnet *ifp = arg; 458 struct ath_softc *sc = ifp->if_softc; 459 struct amrr_softc *asc = (struct amrr_softc *) sc->sc_rc; 460 struct ieee80211com *ic = &sc->sc_ic; 461 int interval; 462 463 if (ifp->if_drv_flags & IFF_DRV_RUNNING) { 464 sc->sc_stats.ast_rate_calls++; 465 466 if (ic->ic_opmode == IEEE80211_M_STA) 467 ath_rate_ctl(sc, ic->ic_bss); /* NB: no reference */ 468 else 469 ieee80211_iterate_nodes(&ic->ic_sta, ath_rate_ctl, sc); 470 } 471 interval = ath_rateinterval; 472 if (ic->ic_opmode == IEEE80211_M_STA) 473 interval /= 2; 474 callout_reset(&asc->timer, (interval * hz) / 1000, 475 ath_ratectl, &sc->sc_if); 476 } 477 478 static void 479 ath_rate_sysctlattach(struct ath_softc *sc) 480 { 481 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 482 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 483 484 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 485 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 486 "rate control: operation interval (ms)"); 487 /* XXX bounds check values */ 488 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 489 "max_sucess_threshold", CTLFLAG_RW, 490 &ath_rate_max_success_threshold, 0, ""); 491 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 492 "min_sucess_threshold", CTLFLAG_RW, 493 &ath_rate_min_success_threshold, 0, ""); 494 } 495 496 struct ath_ratectrl * 497 ath_rate_attach(struct ath_softc *sc) 498 { 499 struct amrr_softc *asc; 500 501 asc = malloc(sizeof(struct amrr_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 502 if (asc == NULL) 503 return NULL; 504 asc->arc.arc_space = sizeof(struct amrr_node); 505 callout_init(&asc->timer, debug_mpsafenet ? CALLOUT_MPSAFE : 0); 506 ath_rate_sysctlattach(sc); 507 508 return &asc->arc; 509 } 510 511 void 512 ath_rate_detach(struct ath_ratectrl *arc) 513 { 514 struct amrr_softc *asc = (struct amrr_softc *) arc; 515 516 callout_drain(&asc->timer); 517 free(asc, M_DEVBUF); 518 } 519