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 #include "opt_wlan.h" 50 51 #include <sys/param.h> 52 #include <sys/systm.h> 53 #include <sys/sysctl.h> 54 #include <sys/module.h> 55 #include <sys/kernel.h> 56 #include <sys/lock.h> 57 #include <sys/mutex.h> 58 #include <sys/errno.h> 59 60 #include <machine/bus.h> 61 #include <machine/resource.h> 62 #include <sys/bus.h> 63 64 #include <sys/socket.h> 65 66 #include <net/if.h> 67 #include <net/if_media.h> 68 #include <net/if_arp.h> 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 static int ath_rateinterval = 1000; /* rate ctl interval (ms) */ 84 static int ath_rate_max_success_threshold = 10; 85 static int ath_rate_min_success_threshold = 1; 86 87 static void ath_rate_update(struct ath_softc *, struct ieee80211_node *, 88 int rate); 89 static void ath_rate_ctl_start(struct ath_softc *, struct ieee80211_node *); 90 static void ath_rate_ctl(void *, struct ieee80211_node *); 91 92 void 93 ath_rate_node_init(struct ath_softc *sc, struct ath_node *an) 94 { 95 /* NB: assumed to be zero'd by caller */ 96 } 97 98 void 99 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 100 { 101 } 102 103 void 104 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 105 int shortPreamble, size_t frameLen, 106 u_int8_t *rix, int *try0, u_int8_t *txrate) 107 { 108 struct amrr_node *amn = ATH_NODE_AMRR(an); 109 110 *rix = amn->amn_tx_rix0; 111 *try0 = amn->amn_tx_try0; 112 if (shortPreamble) 113 *txrate = amn->amn_tx_rate0sp; 114 else 115 *txrate = amn->amn_tx_rate0; 116 } 117 118 void 119 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 120 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 121 { 122 struct amrr_node *amn = ATH_NODE_AMRR(an); 123 124 ath_hal_setupxtxdesc(sc->sc_ah, ds 125 , amn->amn_tx_rate1sp, amn->amn_tx_try1 /* series 1 */ 126 , amn->amn_tx_rate2sp, amn->amn_tx_try2 /* series 2 */ 127 , amn->amn_tx_rate3sp, amn->amn_tx_try3 /* series 3 */ 128 ); 129 } 130 131 void 132 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 133 const struct ath_buf *bf) 134 { 135 struct amrr_node *amn = ATH_NODE_AMRR(an); 136 const struct ath_tx_status *ts = &bf->bf_status.ds_txstat; 137 int sr = ts->ts_shortretry; 138 int lr = ts->ts_longretry; 139 int retry_count = sr + lr; 140 141 amn->amn_tx_try0_cnt++; 142 if (retry_count == 1) { 143 amn->amn_tx_try1_cnt++; 144 } else if (retry_count == 2) { 145 amn->amn_tx_try1_cnt++; 146 amn->amn_tx_try2_cnt++; 147 } else if (retry_count == 3) { 148 amn->amn_tx_try1_cnt++; 149 amn->amn_tx_try2_cnt++; 150 amn->amn_tx_try3_cnt++; 151 } else if (retry_count > 3) { 152 amn->amn_tx_try1_cnt++; 153 amn->amn_tx_try2_cnt++; 154 amn->amn_tx_try3_cnt++; 155 amn->amn_tx_failure_cnt++; 156 } 157 if (amn->amn_interval != 0 && 158 ticks - amn->amn_ticks > amn->amn_interval) { 159 ath_rate_ctl(sc, &an->an_node); 160 amn->amn_ticks = ticks; 161 } 162 } 163 164 void 165 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 166 { 167 if (isnew) 168 ath_rate_ctl_start(sc, &an->an_node); 169 } 170 171 static void 172 node_reset(struct amrr_node *amn) 173 { 174 amn->amn_tx_try0_cnt = 0; 175 amn->amn_tx_try1_cnt = 0; 176 amn->amn_tx_try2_cnt = 0; 177 amn->amn_tx_try3_cnt = 0; 178 amn->amn_tx_failure_cnt = 0; 179 amn->amn_success = 0; 180 amn->amn_recovery = 0; 181 amn->amn_success_threshold = ath_rate_min_success_threshold; 182 } 183 184 185 /** 186 * The code below assumes that we are dealing with hardware multi rate retry 187 * I have no idea what will happen if you try to use this module with another 188 * type of hardware. Your machine might catch fire or it might work with 189 * horrible performance... 190 */ 191 static void 192 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 193 { 194 struct ath_node *an = ATH_NODE(ni); 195 struct amrr_node *amn = ATH_NODE_AMRR(an); 196 struct ieee80211vap *vap = ni->ni_vap; 197 const HAL_RATE_TABLE *rt = sc->sc_currates; 198 u_int8_t rix; 199 200 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 201 202 IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni, 203 "%s: set xmit rate to %dM", __func__, 204 ni->ni_rates.rs_nrates > 0 ? 205 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 206 207 amn->amn_rix = rate; 208 /* 209 * Before associating a node has no rate set setup 210 * so we can't calculate any transmit codes to use. 211 * This is ok since we should never be sending anything 212 * but management frames and those always go at the 213 * lowest hardware rate. 214 */ 215 if (ni->ni_rates.rs_nrates > 0) { 216 ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL; 217 amn->amn_tx_rix0 = sc->sc_rixmap[ni->ni_txrate]; 218 amn->amn_tx_rate0 = rt->info[amn->amn_tx_rix0].rateCode; 219 amn->amn_tx_rate0sp = amn->amn_tx_rate0 | 220 rt->info[amn->amn_tx_rix0].shortPreamble; 221 if (sc->sc_mrretry) { 222 amn->amn_tx_try0 = 1; 223 amn->amn_tx_try1 = 1; 224 amn->amn_tx_try2 = 1; 225 amn->amn_tx_try3 = 1; 226 if (--rate >= 0) { 227 rix = sc->sc_rixmap[ 228 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 229 amn->amn_tx_rate1 = rt->info[rix].rateCode; 230 amn->amn_tx_rate1sp = amn->amn_tx_rate1 | 231 rt->info[rix].shortPreamble; 232 } else { 233 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 234 } 235 if (--rate >= 0) { 236 rix = sc->sc_rixmap[ 237 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 238 amn->amn_tx_rate2 = rt->info[rix].rateCode; 239 amn->amn_tx_rate2sp = amn->amn_tx_rate2 | 240 rt->info[rix].shortPreamble; 241 } else { 242 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 243 } 244 if (rate > 0) { 245 /* NB: only do this if we didn't already do it above */ 246 amn->amn_tx_rate3 = rt->info[0].rateCode; 247 amn->amn_tx_rate3sp = 248 amn->amn_tx_rate3 | rt->info[0].shortPreamble; 249 } else { 250 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 251 } 252 } else { 253 amn->amn_tx_try0 = ATH_TXMAXTRY; 254 /* theorically, these statements are useless because 255 * the code which uses them tests for an_tx_try0 == ATH_TXMAXTRY 256 */ 257 amn->amn_tx_try1 = 0; 258 amn->amn_tx_try2 = 0; 259 amn->amn_tx_try3 = 0; 260 amn->amn_tx_rate1 = amn->amn_tx_rate1sp = 0; 261 amn->amn_tx_rate2 = amn->amn_tx_rate2sp = 0; 262 amn->amn_tx_rate3 = amn->amn_tx_rate3sp = 0; 263 } 264 } 265 node_reset(amn); 266 267 amn->amn_interval = ath_rateinterval; 268 if (vap->iv_opmode == IEEE80211_M_STA) 269 amn->amn_interval /= 2; 270 amn->amn_interval = (amn->amn_interval * hz) / 1000; 271 } 272 273 /* 274 * Set the starting transmit rate for a node. 275 */ 276 static void 277 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 278 { 279 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 280 struct ath_node *an = ATH_NODE(ni); 281 const struct ieee80211_txparam *tp = an->an_tp; 282 int srate; 283 284 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 285 if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) { 286 /* 287 * No fixed rate is requested. For 11b start with 288 * the highest negotiated rate; otherwise, for 11g 289 * and 11a, we start "in the middle" at 24Mb or 36Mb. 290 */ 291 srate = ni->ni_rates.rs_nrates - 1; 292 if (sc->sc_curmode != IEEE80211_MODE_11B) { 293 /* 294 * Scan the negotiated rate set to find the 295 * closest rate. 296 */ 297 /* NB: the rate set is assumed sorted */ 298 for (; srate >= 0 && RATE(srate) > 72; srate--) 299 ; 300 } 301 } else { 302 /* 303 * A fixed rate is to be used; ic_fixed_rate is the 304 * IEEE code for this rate (sans basic bit). Convert this 305 * to the index into the negotiated rate set for 306 * the node. We know the rate is there because the 307 * rate set is checked when the station associates. 308 */ 309 /* NB: the rate set is assumed sorted */ 310 srate = ni->ni_rates.rs_nrates - 1; 311 for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--) 312 ; 313 } 314 /* 315 * The selected rate may not be available due to races 316 * and mode settings. Also orphaned nodes created in 317 * adhoc mode may not have any rate set so this lookup 318 * can fail. This is not fatal. 319 */ 320 ath_rate_update(sc, ni, srate < 0 ? 0 : srate); 321 #undef RATE 322 } 323 324 static void 325 ath_rate_cb(void *arg, struct ieee80211_node *ni) 326 { 327 struct ath_softc *sc = arg; 328 329 ath_rate_update(sc, ni, 0); 330 } 331 332 /* 333 * Reset the rate control state for each 802.11 state transition. 334 */ 335 void 336 ath_rate_newstate(struct ieee80211vap *vap, enum ieee80211_state state) 337 { 338 struct ieee80211com *ic = vap->iv_ic; 339 struct ath_softc *sc = ic->ic_ifp->if_softc; 340 struct ieee80211_node *ni; 341 342 if (state == IEEE80211_S_INIT) 343 return; 344 if (vap->iv_opmode == IEEE80211_M_STA) { 345 /* 346 * Reset local xmit state; this is really only 347 * meaningful when operating in station mode. 348 */ 349 ni = vap->iv_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, vap->iv_bss, 0); 364 } 365 } 366 367 /* 368 * Examine and potentially adjust the transmit rate. 369 */ 370 static void 371 ath_rate_ctl(void *arg, struct ieee80211_node *ni) 372 { 373 struct ath_softc *sc = arg; 374 struct amrr_node *amn = ATH_NODE_AMRR(ATH_NODE (ni)); 375 int rix; 376 377 #define is_success(amn) \ 378 (amn->amn_tx_try1_cnt < (amn->amn_tx_try0_cnt/10)) 379 #define is_enough(amn) \ 380 (amn->amn_tx_try0_cnt > 10) 381 #define is_failure(amn) \ 382 (amn->amn_tx_try1_cnt > (amn->amn_tx_try0_cnt/3)) 383 384 rix = amn->amn_rix; 385 386 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 387 "cnt0: %d cnt1: %d cnt2: %d cnt3: %d -- threshold: %d", 388 amn->amn_tx_try0_cnt, amn->amn_tx_try1_cnt, amn->amn_tx_try2_cnt, 389 amn->amn_tx_try3_cnt, amn->amn_success_threshold); 390 if (is_success (amn) && is_enough (amn)) { 391 amn->amn_success++; 392 if (amn->amn_success == amn->amn_success_threshold && 393 rix + 1 < ni->ni_rates.rs_nrates) { 394 amn->amn_recovery = 1; 395 amn->amn_success = 0; 396 rix++; 397 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 398 "increase rate to %d", rix); 399 } else { 400 amn->amn_recovery = 0; 401 } 402 } else if (is_failure (amn)) { 403 amn->amn_success = 0; 404 if (rix > 0) { 405 if (amn->amn_recovery) { 406 /* recovery failure. */ 407 amn->amn_success_threshold *= 2; 408 amn->amn_success_threshold = min (amn->amn_success_threshold, 409 (u_int)ath_rate_max_success_threshold); 410 IEEE80211_NOTE(ni->ni_vap, 411 IEEE80211_MSG_RATECTL, ni, 412 "decrease rate recovery thr: %d", 413 amn->amn_success_threshold); 414 } else { 415 /* simple failure. */ 416 amn->amn_success_threshold = ath_rate_min_success_threshold; 417 IEEE80211_NOTE(ni->ni_vap, 418 IEEE80211_MSG_RATECTL, ni, 419 "decrease rate normal thr: %d", 420 amn->amn_success_threshold); 421 } 422 amn->amn_recovery = 0; 423 rix--; 424 } else { 425 amn->amn_recovery = 0; 426 } 427 428 } 429 if (is_enough (amn) || rix != amn->amn_rix) { 430 /* reset counters. */ 431 amn->amn_tx_try0_cnt = 0; 432 amn->amn_tx_try1_cnt = 0; 433 amn->amn_tx_try2_cnt = 0; 434 amn->amn_tx_try3_cnt = 0; 435 amn->amn_tx_failure_cnt = 0; 436 } 437 if (rix != amn->amn_rix) { 438 ath_rate_update(sc, ni, rix); 439 } 440 } 441 442 static void 443 ath_rate_sysctlattach(struct ath_softc *sc) 444 { 445 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 446 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 447 448 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 449 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 450 "rate control: operation interval (ms)"); 451 /* XXX bounds check values */ 452 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 453 "max_sucess_threshold", CTLFLAG_RW, 454 &ath_rate_max_success_threshold, 0, ""); 455 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 456 "min_sucess_threshold", CTLFLAG_RW, 457 &ath_rate_min_success_threshold, 0, ""); 458 } 459 460 struct ath_ratectrl * 461 ath_rate_attach(struct ath_softc *sc) 462 { 463 struct amrr_softc *asc; 464 465 asc = malloc(sizeof(struct amrr_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 466 if (asc == NULL) 467 return NULL; 468 asc->arc.arc_space = sizeof(struct amrr_node); 469 ath_rate_sysctlattach(sc); 470 471 return &asc->arc; 472 } 473 474 void 475 ath_rate_detach(struct ath_ratectrl *arc) 476 { 477 struct amrr_softc *asc = (struct amrr_softc *) arc; 478 479 free(asc, M_DEVBUF); 480 } 481 482 /* 483 * Module glue. 484 */ 485 static int 486 amrr_modevent(module_t mod, int type, void *unused) 487 { 488 switch (type) { 489 case MOD_LOAD: 490 if (bootverbose) 491 printf("ath_rate: <AMRR rate control algorithm> version 0.1\n"); 492 return 0; 493 case MOD_UNLOAD: 494 return 0; 495 } 496 return EINVAL; 497 } 498 499 static moduledata_t amrr_mod = { 500 "ath_rate", 501 amrr_modevent, 502 0 503 }; 504 DECLARE_MODULE(ath_rate, amrr_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST); 505 MODULE_VERSION(ath_rate, 1); 506 MODULE_DEPEND(ath_rate, wlan, 1, 1, 1); 507