ieee80211_rssadapt.c revision 1.21.16.3
1 /* $NetBSD: ieee80211_rssadapt.c,v 1.21.16.3 2018/07/16 20:11:11 phil Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (c) 2010 Rui Paulo <rpaulo (at) FreeBSD.org> 7 * Copyright (c) 2003, 2004 David Young. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or 10 * without modification, are permitted provided that the following 11 * conditions are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer in the documentation and/or other materials provided 17 * with the distribution. 18 * 3. The name of David Young may not be used to endorse or promote 19 * products derived from this software without specific prior 20 * written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY David Young ``AS IS'' AND ANY 23 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 24 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 25 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL David 26 * Young BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 27 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 28 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 30 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 33 * OF SUCH DAMAGE. 34 */ 35 #include "opt_wlan.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/kernel.h> 40 #include <sys/malloc.h> 41 #include <sys/module.h> 42 #ifdef __NetBSD__ 43 /* Why doesn't FreeBSD have this? */ 44 #include <sys/sbuf.h> 45 #endif 46 #include <sys/socket.h> 47 #include <sys/sysctl.h> 48 49 #include <net/if.h> 50 #ifdef __FreeBSD__ 51 #include <net/if_var.h> 52 #endif 53 #include <net/if_media.h> 54 #ifdef __FreeBSD__ 55 #include <net/ethernet.h> 56 #endif 57 #ifdef __NetBSD__ 58 #include <net/route.h> 59 #endif 60 61 #include <net80211/ieee80211_var.h> 62 #include <net80211/ieee80211_rssadapt.h> 63 #include <net80211/ieee80211_ratectl.h> 64 65 #ifdef __NetBSD__ 66 #undef KASSERT 67 #define KASSERT(__cond, __complaint) FBSDKASSERT(__cond, __complaint) 68 #endif 69 70 struct rssadapt_expavgctl { 71 /* RSS threshold decay. */ 72 u_int rc_decay_denom; 73 u_int rc_decay_old; 74 /* RSS threshold update. */ 75 u_int rc_thresh_denom; 76 u_int rc_thresh_old; 77 /* RSS average update. */ 78 u_int rc_avgrssi_denom; 79 u_int rc_avgrssi_old; 80 }; 81 82 static struct rssadapt_expavgctl master_expavgctl = { 83 .rc_decay_denom = 16, 84 .rc_decay_old = 15, 85 .rc_thresh_denom = 8, 86 .rc_thresh_old = 4, 87 .rc_avgrssi_denom = 8, 88 .rc_avgrssi_old = 4 89 }; 90 91 #ifdef interpolate 92 #undef interpolate 93 #endif 94 #define interpolate(parm, old, new) ((parm##_old * (old) + \ 95 (parm##_denom - parm##_old) * (new)) / \ 96 parm##_denom) 97 98 static void rssadapt_setinterval(const struct ieee80211vap *, int); 99 static void rssadapt_init(struct ieee80211vap *); 100 static void rssadapt_deinit(struct ieee80211vap *); 101 static void rssadapt_updatestats(struct ieee80211_rssadapt_node *); 102 static void rssadapt_node_init(struct ieee80211_node *); 103 static void rssadapt_node_deinit(struct ieee80211_node *); 104 static int rssadapt_rate(struct ieee80211_node *, void *, uint32_t); 105 static void rssadapt_lower_rate(struct ieee80211_rssadapt_node *, int, int); 106 static void rssadapt_raise_rate(struct ieee80211_rssadapt_node *, 107 int, int); 108 static void rssadapt_tx_complete(const struct ieee80211_node *, 109 const struct ieee80211_ratectl_tx_status *); 110 static void rssadapt_sysctlattach(struct ieee80211vap *, 111 struct sysctl_ctx_list *, struct sysctl_oid *); 112 113 /* number of references from net80211 layer */ 114 static int nrefs = 0; 115 116 #if __FreeBSD__ 117 static const struct ieee80211_ratectl rssadapt = { 118 #elif __NetBSD__ 119 const struct ieee80211_ratectl ratectl_rssadapt = { 120 #endif 121 .ir_name = "rssadapt", 122 .ir_attach = NULL, 123 .ir_detach = NULL, 124 .ir_init = rssadapt_init, 125 .ir_deinit = rssadapt_deinit, 126 .ir_node_init = rssadapt_node_init, 127 .ir_node_deinit = rssadapt_node_deinit, 128 .ir_rate = rssadapt_rate, 129 .ir_tx_complete = rssadapt_tx_complete, 130 .ir_tx_update = NULL, 131 .ir_setinterval = rssadapt_setinterval, 132 }; 133 #if __FreeBSD__ 134 IEEE80211_RATECTL_MODULE(rssadapt, 1); 135 IEEE80211_RATECTL_ALG(rssadapt, IEEE80211_RATECTL_RSSADAPT, rssadapt); 136 #endif 137 138 static void 139 rssadapt_setinterval(const struct ieee80211vap *vap, int msecs) 140 { 141 struct ieee80211_rssadapt *rs = vap->iv_rs; 142 int t; 143 144 if (msecs < 100) 145 msecs = 100; 146 t = msecs_to_ticks(msecs); 147 rs->interval = (t < 1) ? 1 : t; 148 } 149 150 static void 151 rssadapt_init(struct ieee80211vap *vap) 152 { 153 struct ieee80211_rssadapt *rs; 154 155 KASSERT(vap->iv_rs == NULL, ("%s: iv_rs already initialized", 156 __func__)); 157 158 nrefs++; /* XXX locking */ 159 vap->iv_rs = rs = IEEE80211_MALLOC(sizeof(struct ieee80211_rssadapt), 160 M_80211_RATECTL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 161 if (rs == NULL) { 162 if_printf(vap->iv_ifp, "couldn't alloc ratectl structure\n"); 163 return; 164 } 165 rs->vap = vap; 166 rssadapt_setinterval(vap, 500 /* msecs */); 167 rssadapt_sysctlattach(vap, vap->iv_sysctl, vap->iv_oid); 168 } 169 170 static void 171 rssadapt_deinit(struct ieee80211vap *vap) 172 { 173 IEEE80211_FREE(vap->iv_rs, M_80211_RATECTL); 174 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 175 nrefs--; /* XXX locking */ 176 } 177 178 static void 179 rssadapt_updatestats(struct ieee80211_rssadapt_node *ra) 180 { 181 long interval; 182 183 ra->ra_pktrate = (ra->ra_pktrate + 10*(ra->ra_nfail + ra->ra_nok))/2; 184 ra->ra_nfail = ra->ra_nok = 0; 185 186 /* 187 * A node is eligible for its rate to be raised every 1/10 to 10 188 * seconds, more eligible in proportion to recent packet rates. 189 */ 190 interval = MAX(10*1000, 10*1000 / MAX(1, 10 * ra->ra_pktrate)); 191 ra->ra_raise_interval = msecs_to_ticks(interval); 192 } 193 194 static void 195 rssadapt_node_init(struct ieee80211_node *ni) 196 { 197 struct ieee80211_rssadapt_node *ra; 198 struct ieee80211vap *vap = ni->ni_vap; 199 struct ieee80211_rssadapt *rsa = vap->iv_rs; 200 const struct ieee80211_rateset *rs = &ni->ni_rates; 201 202 if (ni->ni_rctls == NULL) { 203 ni->ni_rctls = ra = 204 IEEE80211_MALLOC(sizeof(struct ieee80211_rssadapt_node), 205 M_80211_RATECTL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 206 if (ra == NULL) { 207 if_printf(vap->iv_ifp, "couldn't alloc per-node ratectl " 208 "structure\n"); 209 return; 210 } 211 } else 212 ra = ni->ni_rctls; 213 ra->ra_rs = rsa; 214 ra->ra_rates = *rs; 215 rssadapt_updatestats(ra); 216 217 /* pick initial rate */ 218 for (ra->ra_rix = rs->rs_nrates - 1; 219 ra->ra_rix > 0 && (rs->rs_rates[ra->ra_rix] & IEEE80211_RATE_VAL) > 72; 220 ra->ra_rix--) 221 ; 222 ni->ni_txrate = rs->rs_rates[ra->ra_rix] & IEEE80211_RATE_VAL; 223 ra->ra_ticks = ticks; 224 225 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 226 "RSSADAPT initial rate %d", ni->ni_txrate); 227 } 228 229 static void 230 rssadapt_node_deinit(struct ieee80211_node *ni) 231 { 232 233 IEEE80211_FREE(ni->ni_rctls, M_80211_RATECTL); 234 } 235 236 static __inline int 237 bucket(int pktlen) 238 { 239 int i, top, thridx; 240 241 for (i = 0, top = IEEE80211_RSSADAPT_BKT0; 242 i < IEEE80211_RSSADAPT_BKTS; 243 i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) { 244 thridx = i; 245 if (pktlen <= top) 246 break; 247 } 248 return thridx; 249 } 250 251 static int 252 rssadapt_rate(struct ieee80211_node *ni, void *arg __unused, uint32_t iarg) 253 { 254 struct ieee80211_rssadapt_node *ra = ni->ni_rctls; 255 u_int pktlen = iarg; 256 const struct ieee80211_rateset *rs = &ra->ra_rates; 257 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 258 int rix, rssi; 259 260 if ((ticks - ra->ra_ticks) > ra->ra_rs->interval) { 261 rssadapt_updatestats(ra); 262 ra->ra_ticks = ticks; 263 } 264 265 thrs = &ra->ra_rate_thresh[bucket(pktlen)]; 266 267 /* XXX this is average rssi, should be using last value */ 268 rssi = ni->ni_ic->ic_node_getrssi(ni); 269 for (rix = rs->rs_nrates-1; rix >= 0; rix--) 270 if ((*thrs)[rix] < (rssi << 8)) 271 break; 272 if (rix != ra->ra_rix) { 273 /* update public rate */ 274 ni->ni_txrate = ni->ni_rates.rs_rates[rix] & IEEE80211_RATE_VAL; 275 ra->ra_rix = rix; 276 277 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 278 "RSSADAPT new rate %d (pktlen %d rssi %d)", 279 ni->ni_txrate, pktlen, rssi); 280 } 281 return rix; 282 } 283 284 /* 285 * Adapt the data rate to suit the conditions. When a transmitted 286 * packet is dropped after RAL_RSSADAPT_RETRY_LIMIT retransmissions, 287 * raise the RSS threshold for transmitting packets of similar length at 288 * the same data rate. 289 */ 290 static void 291 rssadapt_lower_rate(struct ieee80211_rssadapt_node *ra, int pktlen, int rssi) 292 { 293 uint16_t last_thr; 294 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 295 u_int rix; 296 297 thrs = &ra->ra_rate_thresh[bucket(pktlen)]; 298 299 rix = ra->ra_rix; 300 last_thr = (*thrs)[rix]; 301 (*thrs)[rix] = interpolate(master_expavgctl.rc_thresh, 302 last_thr, (rssi << 8)); 303 304 IEEE80211_DPRINTF(ra->ra_rs->vap, IEEE80211_MSG_RATECTL, 305 "RSSADAPT lower threshold for rate %d (last_thr %d new thr %d rssi %d)\n", 306 ra->ra_rates.rs_rates[rix + 1] & IEEE80211_RATE_VAL, 307 last_thr, (*thrs)[rix], rssi); 308 } 309 310 static void 311 rssadapt_raise_rate(struct ieee80211_rssadapt_node *ra, int pktlen, int rssi) 312 { 313 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 314 uint16_t newthr, oldthr; 315 int rix; 316 317 thrs = &ra->ra_rate_thresh[bucket(pktlen)]; 318 319 rix = ra->ra_rix; 320 if ((*thrs)[rix + 1] > (*thrs)[rix]) { 321 oldthr = (*thrs)[rix + 1]; 322 if ((*thrs)[rix] == 0) 323 newthr = (rssi << 8); 324 else 325 newthr = (*thrs)[rix]; 326 (*thrs)[rix + 1] = interpolate(master_expavgctl.rc_decay, 327 oldthr, newthr); 328 329 IEEE80211_DPRINTF(ra->ra_rs->vap, IEEE80211_MSG_RATECTL, 330 "RSSADAPT raise threshold for rate %d (oldthr %d newthr %d rssi %d)\n", 331 ra->ra_rates.rs_rates[rix + 1] & IEEE80211_RATE_VAL, 332 oldthr, newthr, rssi); 333 334 ra->ra_last_raise = ticks; 335 } 336 } 337 338 static void 339 rssadapt_tx_complete(const struct ieee80211_node *ni, 340 const struct ieee80211_ratectl_tx_status *status) 341 { 342 struct ieee80211_rssadapt_node *ra = ni->ni_rctls; 343 int pktlen, rssi; 344 345 if ((status->flags & 346 (IEEE80211_RATECTL_STATUS_PKTLEN|IEEE80211_RATECTL_STATUS_RSSI)) != 347 (IEEE80211_RATECTL_STATUS_PKTLEN|IEEE80211_RATECTL_STATUS_RSSI)) 348 return; 349 350 pktlen = status->pktlen; 351 rssi = status->rssi; 352 353 if (status->status == IEEE80211_RATECTL_TX_SUCCESS) { 354 ra->ra_nok++; 355 if ((ra->ra_rix + 1) < ra->ra_rates.rs_nrates && 356 (ticks - ra->ra_last_raise) >= ra->ra_raise_interval) 357 rssadapt_raise_rate(ra, pktlen, rssi); 358 } else { 359 ra->ra_nfail++; 360 rssadapt_lower_rate(ra, pktlen, rssi); 361 } 362 } 363 364 #ifdef notyet 365 static int 366 rssadapt_sysctl_interval(SYSCTL_HANDLER_ARGS) 367 { 368 struct ieee80211vap *vap = arg1; 369 struct ieee80211_rssadapt *rs = vap->iv_rs; 370 int msecs = ticks_to_msecs(rs->interval); 371 int error; 372 373 error = sysctl_handle_int(oidp, &msecs, 0, req); 374 if (error || !req->newptr) 375 return error; 376 rssadapt_setinterval(vap, msecs); 377 return 0; 378 } 379 #endif 380 381 static void 382 rssadapt_sysctlattach(struct ieee80211vap *vap, 383 struct sysctl_ctx_list *ctx, struct sysctl_oid *tree) 384 { 385 #ifdef notyet 386 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 387 "rssadapt_rate_interval", CTLTYPE_INT | CTLFLAG_RW, vap, 388 0, rssadapt_sysctl_interval, "I", "rssadapt operation interval (ms)"); 389 #endif 390 } 391
Indexes created Tue Sep 30 20:09:53 GMT 2025