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 } 199 200 201 static void 202 ath_rate_update(struct ath_softc *sc, struct ieee80211_node *ni, int rate) 203 { 204 struct ath_node *an = ATH_NODE(ni); 205 struct onoe_node *on = ATH_NODE_ONOE(an); 206 struct ieee80211vap *vap = ni->ni_vap; 207 const HAL_RATE_TABLE *rt = sc->sc_currates; 208 u_int8_t rix; 209 210 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 211 212 IEEE80211_NOTE(vap, IEEE80211_MSG_RATECTL, ni, 213 "%s: set xmit rate to %dM", __func__, 214 ni->ni_rates.rs_nrates > 0 ? 215 (ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL) / 2 : 0); 216 217 /* 218 * Before associating a node has no rate set setup 219 * so we can't calculate any transmit codes to use. 220 * This is ok since we should never be sending anything 221 * but management frames and those always go at the 222 * lowest hardware rate. 223 */ 224 if (ni->ni_rates.rs_nrates == 0) 225 goto done; 226 on->on_rix = rate; 227 ni->ni_txrate = ni->ni_rates.rs_rates[rate] & IEEE80211_RATE_VAL; 228 on->on_tx_rix0 = sc->sc_rixmap[ni->ni_txrate]; 229 on->on_tx_rate0 = rt->info[on->on_tx_rix0].rateCode; 230 231 on->on_tx_rate0sp = on->on_tx_rate0 | 232 rt->info[on->on_tx_rix0].shortPreamble; 233 if (sc->sc_mrretry) { 234 /* 235 * Hardware supports multi-rate retry; setup two 236 * step-down retry rates and make the lowest rate 237 * be the ``last chance''. We use 4, 2, 2, 2 tries 238 * respectively (4 is set here, the rest are fixed 239 * in the xmit routine). 240 */ 241 on->on_tx_try0 = 1 + 3; /* 4 tries at rate 0 */ 242 if (--rate >= 0) { 243 rix = sc->sc_rixmap[ 244 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 245 on->on_tx_rate1 = rt->info[rix].rateCode; 246 on->on_tx_rate1sp = on->on_tx_rate1 | 247 rt->info[rix].shortPreamble; 248 } else { 249 on->on_tx_rate1 = on->on_tx_rate1sp = 0; 250 } 251 if (--rate >= 0) { 252 rix = sc->sc_rixmap[ 253 ni->ni_rates.rs_rates[rate]&IEEE80211_RATE_VAL]; 254 on->on_tx_rate2 = rt->info[rix].rateCode; 255 on->on_tx_rate2sp = on->on_tx_rate2 | 256 rt->info[rix].shortPreamble; 257 } else { 258 on->on_tx_rate2 = on->on_tx_rate2sp = 0; 259 } 260 if (rate > 0) { 261 /* NB: only do this if we didn't already do it above */ 262 on->on_tx_rate3 = rt->info[0].rateCode; 263 on->on_tx_rate3sp = 264 on->on_tx_rate3 | rt->info[0].shortPreamble; 265 } else { 266 on->on_tx_rate3 = on->on_tx_rate3sp = 0; 267 } 268 } else { 269 on->on_tx_try0 = ATH_TXMAXTRY; /* max tries at rate 0 */ 270 on->on_tx_rate1 = on->on_tx_rate1sp = 0; 271 on->on_tx_rate2 = on->on_tx_rate2sp = 0; 272 on->on_tx_rate3 = on->on_tx_rate3sp = 0; 273 } 274 done: 275 on->on_tx_ok = on->on_tx_err = on->on_tx_retr = on->on_tx_upper = 0; 276 277 on->on_interval = ath_rateinterval; 278 if (vap->iv_opmode == IEEE80211_M_STA) 279 on->on_interval /= 2; 280 on->on_interval = (on->on_interval * hz) / 1000; 281 } 282 283 /* 284 * Set the starting transmit rate for a node. 285 */ 286 static void 287 ath_rate_ctl_start(struct ath_softc *sc, struct ieee80211_node *ni) 288 { 289 #define RATE(_ix) (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL) 290 const struct ieee80211_txparam *tp = ni->ni_txparms; 291 int srate; 292 293 KASSERT(ni->ni_rates.rs_nrates > 0, ("no rates")); 294 if (tp == NULL || tp->ucastrate == IEEE80211_FIXED_RATE_NONE) { 295 /* 296 * No fixed rate is requested. For 11b start with 297 * the highest negotiated rate; otherwise, for 11g 298 * and 11a, we start "in the middle" at 24Mb or 36Mb. 299 */ 300 srate = ni->ni_rates.rs_nrates - 1; 301 if (sc->sc_curmode != IEEE80211_MODE_11B) { 302 /* 303 * Scan the negotiated rate set to find the 304 * closest rate. 305 */ 306 /* NB: the rate set is assumed sorted */ 307 for (; srate >= 0 && RATE(srate) > 72; srate--) 308 ; 309 } 310 } else { 311 /* 312 * A fixed rate is to be used; ic_fixed_rate is the 313 * IEEE code for this rate (sans basic bit). Convert this 314 * to the index into the negotiated rate set for 315 * the node. We know the rate is there because the 316 * rate set is checked when the station associates. 317 */ 318 /* NB: the rate set is assumed sorted */ 319 srate = ni->ni_rates.rs_nrates - 1; 320 for (; srate >= 0 && RATE(srate) != tp->ucastrate; srate--) 321 ; 322 } 323 /* 324 * The selected rate may not be available due to races 325 * and mode settings. Also orphaned nodes created in 326 * adhoc mode may not have any rate set so this lookup 327 * can fail. This is not fatal. 328 */ 329 ath_rate_update(sc, ni, srate < 0 ? 0 : srate); 330 #undef RATE 331 } 332 333 /* 334 * Examine and potentially adjust the transmit rate. 335 */ 336 static void 337 ath_rate_ctl(void *arg, struct ieee80211_node *ni) 338 { 339 struct ath_softc *sc = arg; 340 struct onoe_node *on = ATH_NODE_ONOE(ATH_NODE(ni)); 341 struct ieee80211_rateset *rs = &ni->ni_rates; 342 int dir = 0, nrate, enough; 343 344 /* 345 * Rate control 346 * XXX: very primitive version. 347 */ 348 enough = (on->on_tx_ok + on->on_tx_err >= 10); 349 350 /* no packet reached -> down */ 351 if (on->on_tx_err > 0 && on->on_tx_ok == 0) 352 dir = -1; 353 354 /* all packets needs retry in average -> down */ 355 if (enough && on->on_tx_ok < on->on_tx_retr) 356 dir = -1; 357 358 /* no error and less than rate_raise% of packets need retry -> up */ 359 if (enough && on->on_tx_err == 0 && 360 on->on_tx_retr < (on->on_tx_ok * ath_rate_raise) / 100) 361 dir = 1; 362 363 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 364 "ok %d err %d retr %d upper %d dir %d", 365 on->on_tx_ok, on->on_tx_err, on->on_tx_retr, on->on_tx_upper, dir); 366 367 nrate = on->on_rix; 368 switch (dir) { 369 case 0: 370 if (enough && on->on_tx_upper > 0) 371 on->on_tx_upper--; 372 break; 373 case -1: 374 if (nrate > 0) { 375 nrate--; 376 sc->sc_stats.ast_rate_drop++; 377 } 378 on->on_tx_upper = 0; 379 break; 380 case 1: 381 /* raise rate if we hit rate_raise_threshold */ 382 if (++on->on_tx_upper < ath_rate_raise_threshold) 383 break; 384 on->on_tx_upper = 0; 385 if (nrate + 1 < rs->rs_nrates) { 386 nrate++; 387 sc->sc_stats.ast_rate_raise++; 388 } 389 break; 390 } 391 392 if (nrate != on->on_rix) { 393 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 394 "%s: %dM -> %dM (%d ok, %d err, %d retr)", __func__, 395 ni->ni_txrate / 2, 396 (rs->rs_rates[nrate] & IEEE80211_RATE_VAL) / 2, 397 on->on_tx_ok, on->on_tx_err, on->on_tx_retr); 398 ath_rate_update(sc, ni, nrate); 399 } else if (enough) 400 on->on_tx_ok = on->on_tx_err = on->on_tx_retr = 0; 401 } 402 403 static void 404 ath_rate_sysctlattach(struct ath_softc *sc) 405 { 406 struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev); 407 struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev); 408 409 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 410 "rate_interval", CTLFLAG_RW, &ath_rateinterval, 0, 411 "rate control: operation interval (ms)"); 412 /* XXX bounds check values */ 413 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 414 "rate_raise", CTLFLAG_RW, &ath_rate_raise, 0, 415 "rate control: retry threshold to credit rate raise (%%)"); 416 SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 417 "rate_raise_threshold", CTLFLAG_RW, &ath_rate_raise_threshold,0, 418 "rate control: # good periods before raising rate"); 419 } 420 421 static int 422 ath_rate_fetch_node_stats(struct ath_softc *sc, struct ath_node *an, 423 struct ath_rateioctl *re) 424 { 425 426 return (EINVAL); 427 } 428 429 struct ath_ratectrl * 430 ath_rate_attach(struct ath_softc *sc) 431 { 432 struct onoe_softc *osc; 433 434 osc = malloc(sizeof(struct onoe_softc), M_DEVBUF, M_NOWAIT|M_ZERO); 435 if (osc == NULL) 436 return NULL; 437 osc->arc.arc_space = sizeof(struct onoe_node); 438 ath_rate_sysctlattach(sc); 439 440 return &osc->arc; 441 } 442 443 void 444 ath_rate_detach(struct ath_ratectrl *arc) 445 { 446 struct onoe_softc *osc = (struct onoe_softc *) arc; 447 448 free(osc, M_DEVBUF); 449 } 450