1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2002-2007 Sam Leffler, Errno Consulting 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer, 12 * without modification. 13 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 14 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 15 * redistribution must be conditioned upon including a substantially 16 * similar Disclaimer requirement for further binary redistribution. 17 * 18 * NO WARRANTY 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 22 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 23 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 24 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 27 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 29 * THE POSSIBILITY OF SUCH DAMAGES. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 /* 36 * Atsushi Onoe's rate control algorithm. 37 */ 38 #include "opt_ath.h" 39 #include "opt_inet.h" 40 #include "opt_wlan.h" 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/sysctl.h> 45 #include <sys/kernel.h> 46 #include <sys/lock.h> 47 #include <sys/mutex.h> 48 #include <sys/errno.h> 49 50 #include <machine/bus.h> 51 #include <machine/resource.h> 52 #include <sys/bus.h> 53 54 #include <sys/socket.h> 55 56 #include <net/if.h> 57 #include <net/if_media.h> 58 #include <net/if_arp.h> 59 #include <net/ethernet.h> /* XXX for ether_sprintf */ 60 61 #include <net80211/ieee80211_var.h> 62 63 #include <net/bpf.h> 64 65 #ifdef INET 66 #include <netinet/in.h> 67 #include <netinet/if_ether.h> 68 #endif 69 70 #include <dev/ath/if_athvar.h> 71 #include <dev/ath/ath_rate/onoe/onoe.h> 72 #include <dev/ath/ath_hal/ah_desc.h> 73 74 /* 75 * Default parameters for the rate control algorithm. These are 76 * all tunable with sysctls. The rate controller runs periodically 77 * (each ath_rateinterval ms) analyzing transmit statistics for each 78 * neighbor/station (when operating in station mode this is only the AP). 79 * If transmits look to be working well over a sampling period then 80 * it gives a "raise rate credit". If transmits look to not be working 81 * well than it deducts a credit. If the credits cross a threshold then 82 * the transmit rate is raised. Various error conditions force the 83 * the transmit rate to be dropped. 84 * 85 * The decision to issue/deduct a credit is based on the errors and 86 * retries accumulated over the sampling period. ath_rate_raise defines 87 * the percent of retransmits for which a credit is issued/deducted. 88 * ath_rate_raise_threshold defines the threshold on credits at which 89 * the transmit rate is increased. 90 * 91 * XXX this algorithm is flawed. 92 */ 93 static int ath_rateinterval = 1000; /* rate ctl interval (ms) */ 94 static int ath_rate_raise = 10; /* add credit threshold */ 95 static int ath_rate_raise_threshold = 10; /* rate ctl raise threshold */ 96 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 } 107 108 void 109 ath_rate_node_cleanup(struct ath_softc *sc, struct ath_node *an) 110 { 111 } 112 113 void 114 ath_rate_findrate(struct ath_softc *sc, struct ath_node *an, 115 int shortPreamble, size_t frameLen, int tid, int is_aggr, 116 u_int8_t *rix, int *try0, u_int8_t *txrate, int *maxdur, 117 int *maxpktlen) 118 { 119 struct onoe_node *on = ATH_NODE_ONOE(an); 120 121 *rix = on->on_tx_rix0; 122 *try0 = on->on_tx_try0; 123 if (shortPreamble) 124 *txrate = on->on_tx_rate0sp; 125 else 126 *txrate = on->on_tx_rate0; 127 *maxdur = -1; 128 *maxpktlen = -1; 129 } 130 131 /* 132 * Get the TX rates. 133 * 134 * The short preamble bits aren't set here; the caller should augment 135 * the returned rate with the relevant preamble rate flag. 136 */ 137 void 138 ath_rate_getxtxrates(struct ath_softc *sc, struct ath_node *an, 139 uint8_t rix0, int is_aggr, struct ath_rc_series *rc) 140 { 141 struct onoe_node *on = ATH_NODE_ONOE(an); 142 143 rc[0].flags = rc[1].flags = rc[2].flags = rc[3].flags = 0; 144 145 rc[0].rix = on->on_tx_rate0; 146 rc[1].rix = on->on_tx_rate1; 147 rc[2].rix = on->on_tx_rate2; 148 rc[3].rix = on->on_tx_rate3; 149 150 rc[0].tries = on->on_tx_try0; 151 rc[1].tries = 2; 152 rc[2].tries = 2; 153 rc[3].tries = 2; 154 } 155 156 void 157 ath_rate_setupxtxdesc(struct ath_softc *sc, struct ath_node *an, 158 struct ath_desc *ds, int shortPreamble, u_int8_t rix) 159 { 160 struct onoe_node *on = ATH_NODE_ONOE(an); 161 162 ath_hal_setupxtxdesc(sc->sc_ah, ds 163 , on->on_tx_rate1sp, 2 /* series 1 */ 164 , on->on_tx_rate2sp, 2 /* series 2 */ 165 , on->on_tx_rate3sp, 2 /* series 3 */ 166 ); 167 } 168 169 void 170 ath_rate_tx_complete(struct ath_softc *sc, struct ath_node *an, 171 const struct ath_rc_series *rc, const struct ath_tx_status *ts, 172 int frame_size, int rc_framesize, int nframes, int nbad) 173 { 174 struct onoe_node *on = ATH_NODE_ONOE(an); 175 176 if (ts->ts_status == 0) 177 on->on_tx_ok++; 178 else 179 on->on_tx_err++; 180 on->on_tx_retr += ts->ts_shortretry 181 + ts->ts_longretry; 182 if (on->on_interval != 0 && ticks - on->on_ticks > on->on_interval) { 183 ath_rate_ctl(sc, &an->an_node); 184 on->on_ticks = ticks; 185 } 186 } 187 188 void 189 ath_rate_newassoc(struct ath_softc *sc, struct ath_node *an, int isnew) 190 { 191 if (isnew) 192 ath_rate_ctl_start(sc, &an->an_node); 193 } 194 195 void 196 ath_rate_update_rx_rssi(struct ath_softc *sc, struct ath_node *an, int rssi) 197 { 198 } 199 200 static void 201 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 202 { 203 struct ath_node *an = ATH_NODE(ni); 204 struct onoe_node *on = ATH_NODE_ONOE(an); 205 struct ieee80211vap *vap = ni->ni_vap; 206 const HAL_RATE_TABLE *rt = sc->sc_currates; 207 u_int8_t rix; 208 209 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 210 211 IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni, 212 "%s: set xmit rate to %dM", __func__, 213 ni->ni_rates.rs_nrates > 0 ? 214 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 215 216 /* 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 goto done; 225 on->on_rix = rate; 226 ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL; 227 on->on_tx_rix0 = sc->sc_rixmap[ni->ni_txrate]; 228 on->on_tx_rate0 = rt->info[on->on_tx_rix0].rateCode; 229 230 on->on_tx_rate0sp = on->on_tx_rate0 | 231 rt->info[on->on_tx_rix0].shortPreamble; 232 if (sc->sc_mrretry) { 233 /* 234 * Hardware supports multi-rate retry; setup two 235 * step-down retry rates and make the lowest rate 236 * be the ``last chance''. We use 4, 2, 2, 2 tries 237 * respectively (4 is set here, the rest are fixed 238 * in the xmit routine). 239 */ 240 on->on_tx_try0 = 1 + 3; /* 4 tries at rate 0 */ 241 if (--rate >= 0) { 242 rix = sc->sc_rixmap[ 243 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 244 on->on_tx_rate1 = rt->info[rix].rateCode; 245 on->on_tx_rate1sp = on->on_tx_rate1 | 246 rt->info[rix].shortPreamble; 247 } else { 248 on->on_tx_rate1 = on->on_tx_rate1sp = 0; 249 } 250 if (--rate >= 0) { 251 rix = sc->sc_rixmap[ 252 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 253 on->on_tx_rate2 = rt->info[rix].rateCode; 254 on->on_tx_rate2sp = on->on_tx_rate2 | 255 rt->info[rix].shortPreamble; 256 } else { 257 on->on_tx_rate2 = on->on_tx_rate2sp = 0; 258 } 259 if (rate > 0) { 260 /* NB: only do this if we didn't already do it above */ 261 on->on_tx_rate3 = rt->info[0].rateCode; 262 on->on_tx_rate3sp = 263 on->on_tx_rate3 | rt->info[0].shortPreamble; 264 } else { 265 on->on_tx_rate3 = on->on_tx_rate3sp = 0; 266 } 267 } else { 268 on->on_tx_try0 = ATH_TXMAXTRY; /* max tries at rate 0 */ 269 on->on_tx_rate1 = on->on_tx_rate1sp = 0; 270 on->on_tx_rate2 = on->on_tx_rate2sp = 0; 271 on->on_tx_rate3 = on->on_tx_rate3sp = 0; 272 } 273 done: 274 on->on_tx_ok = on->on_tx_err = on->on_tx_retr = on->on_tx_upper = 0; 275 276 on->on_interval = ath_rateinterval; 277 if (vap->iv_opmode == IEEE80211_M_STA) 278 on->on_interval /= 2; 279 on->on_interval = (on->on_interval * hz) / 1000; 280 } 281 282 /* 283 * Set the starting transmit rate for a node. 284 */ 285 static void 286 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 287 { 288 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 289 const struct ieee80211_txparam *tp = ni->ni_txparms; 290 int srate; 291 292 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 293 if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) { 294 /* 295 * No fixed rate is requested. For 11b start with 296 * the highest negotiated rate; otherwise, for 11g 297 * and 11a, we start "in the middle" at 24Mb or 36Mb. 298 */ 299 srate = ni->ni_rates.rs_nrates - 1; 300 if (sc->sc_curmode != IEEE80211_MODE_11B) { 301 /* 302 * Scan the negotiated rate set to find the 303 * closest rate. 304 */ 305 /* NB: the rate set is assumed sorted */ 306 for (; srate >= 0 && RATE(srate) > 72; srate--) 307 ; 308 } 309 } else { 310 /* 311 * A fixed rate is to be used; ic_fixed_rate is the 312 * IEEE code for this rate (sans basic bit). Convert this 313 * to the index into the negotiated rate set for 314 * the node. We know the rate is there because the 315 * rate set is checked when the station associates. 316 */ 317 /* NB: the rate set is assumed sorted */ 318 srate = ni->ni_rates.rs_nrates - 1; 319 for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--) 320 ; 321 } 322 /* 323 * The selected rate may not be available due to races 324 * and mode settings. Also orphaned nodes created in 325 * adhoc mode may not have any rate set so this lookup 326 * can fail. This is not fatal. 327 */ 328 ath_rate_update(sc, ni, srate < 0 ? 0 : srate); 329 #undef RATE 330 } 331 332 /* 333 * Examine and potentially adjust the transmit rate. 334 */ 335 static void 336 ath_rate_ctl(void *arg, struct ieee80211_node *ni) 337 { 338 struct ath_softc *sc = arg; 339 struct onoe_node *on = ATH_NODE_ONOE(ATH_NODE(ni)); 340 struct ieee80211_rateset *rs = &ni->ni_rates; 341 int dir = 0, nrate, enough; 342 343 /* 344 * Rate control 345 * XXX: very primitive version. 346 */ 347 enough = (on->on_tx_ok + on->on_tx_err >= 10); 348 349 /* no packet reached -> down */ 350 if (on->on_tx_err > 0 && on->on_tx_ok == 0) 351 dir = -1; 352 353 /* all packets needs retry in average -> down */ 354 if (enough && on->on_tx_ok < on->on_tx_retr) 355 dir = -1; 356 357 /* no error and less than rate_raise% of packets need retry -> up */ 358 if (enough && on->on_tx_err == 0 && 359 on->on_tx_retr < (on->on_tx_ok * ath_rate_raise) / 100) 360 dir = 1; 361 362 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 363 "ok %d err %d retr %d upper %d dir %d", 364 on->on_tx_ok, on->on_tx_err, on->on_tx_retr, on->on_tx_upper, dir); 365 366 nrate = on->on_rix; 367 switch (dir) { 368 case 0: 369 if (enough && on->on_tx_upper > 0) 370 on->on_tx_upper--; 371 break; 372 case -1: 373 if (nrate > 0) { 374 nrate--; 375 sc->sc_stats.ast_rate_drop++; 376 } 377 on->on_tx_upper = 0; 378 break; 379 case 1: 380 /* raise rate if we hit rate_raise_threshold */ 381 if (++on->on_tx_upper < ath_rate_raise_threshold) 382 break; 383 on->on_tx_upper = 0; 384 if (nrate + 1 < rs->rs_nrates) { 385 nrate++; 386 sc->sc_stats.ast_rate_raise++; 387 } 388 break; 389 } 390 391 if (nrate != on->on_rix) { 392 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 393 "%s: %dM -> %dM (%d ok, %d err, %d retr)", __func__, 394 ni->ni_txrate / 2, 395 (rs->rs_rates[nrate] & IEEE80211_RATE_VAL) / 2, 396 on->on_tx_ok, on->on_tx_err, on->on_tx_retr); 397 ath_rate_update(sc, ni, nrate); 398 } else if (enough) 399 on->on_tx_ok = on->on_tx_err = on->on_tx_retr = 0; 400 } 401 402 static void 403 ath_rate_sysctlattach(struct ath_softc *sc) 404 { 405 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 406 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 407 408 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 409 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 410 "rate control: operation interval (ms)"); 411 /* XXX bounds check values */ 412 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 413 "rate_raise", CTLFLAG_RW, &ath_rate_raise, 0, 414 "rate control: retry threshold to credit rate raise (%%)"); 415 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 416 "rate_raise_threshold", CTLFLAG_RW, &ath_rate_raise_threshold,0, 417 "rate control: # good periods before raising rate"); 418 } 419 420 static int 421 ath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an, 422 struct ath_rateioctl *re) 423 { 424 425 return (EINVAL); 426 } 427 428 struct ath_ratectrl * 429 ath_rate_attach(struct ath_softc *sc) 430 { 431 struct onoe_softc *osc; 432 433 osc = malloc(sizeof(struct onoe_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 434 if (osc == NULL) 435 return NULL; 436 osc->arc.arc_space = sizeof(struct onoe_node); 437 ath_rate_sysctlattach(sc); 438 439 return &osc->arc; 440 } 441 442 void 443 ath_rate_detach(struct ath_ratectrl *arc) 444 { 445 struct onoe_softc *osc = (struct onoe_softc *) arc; 446 447 free(osc, M_DEVBUF); 448 } 449