ieee80211_rssadapt.c revision 1.21.16.2
1 /* $NetBSD: ieee80211_rssadapt.c,v 1.21.16.2 2018/07/12 16:35:34 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 static const struct ieee80211_ratectl rssadapt __unused = { 117 .ir_name = "rssadapt", 118 .ir_attach = NULL, 119 .ir_detach = NULL, 120 .ir_init = rssadapt_init, 121 .ir_deinit = rssadapt_deinit, 122 .ir_node_init = rssadapt_node_init, 123 .ir_node_deinit = rssadapt_node_deinit, 124 .ir_rate = rssadapt_rate, 125 .ir_tx_complete = rssadapt_tx_complete, 126 .ir_tx_update = NULL, 127 .ir_setinterval = rssadapt_setinterval, 128 }; 129 IEEE80211_RATECTL_MODULE(rssadapt, 1); 130 IEEE80211_RATECTL_ALG(rssadapt, IEEE80211_RATECTL_RSSADAPT, rssadapt); 131 132 static void 133 rssadapt_setinterval(const struct ieee80211vap *vap, int msecs) 134 { 135 struct ieee80211_rssadapt *rs = vap->iv_rs; 136 int t; 137 138 if (msecs < 100) 139 msecs = 100; 140 t = msecs_to_ticks(msecs); 141 rs->interval = (t < 1) ? 1 : t; 142 } 143 144 static void 145 rssadapt_init(struct ieee80211vap *vap) 146 { 147 struct ieee80211_rssadapt *rs; 148 149 KASSERT(vap->iv_rs == NULL, ("%s: iv_rs already initialized", 150 __func__)); 151 152 nrefs++; /* XXX locking */ 153 vap->iv_rs = rs = IEEE80211_MALLOC(sizeof(struct ieee80211_rssadapt), 154 M_80211_RATECTL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 155 if (rs == NULL) { 156 if_printf(vap->iv_ifp, "couldn't alloc ratectl structure\n"); 157 return; 158 } 159 rs->vap = vap; 160 rssadapt_setinterval(vap, 500 /* msecs */); 161 rssadapt_sysctlattach(vap, vap->iv_sysctl, vap->iv_oid); 162 } 163 164 static void 165 rssadapt_deinit(struct ieee80211vap *vap) 166 { 167 IEEE80211_FREE(vap->iv_rs, M_80211_RATECTL); 168 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 169 nrefs--; /* XXX locking */ 170 } 171 172 static void 173 rssadapt_updatestats(struct ieee80211_rssadapt_node *ra) 174 { 175 long interval; 176 177 ra->ra_pktrate = (ra->ra_pktrate + 10*(ra->ra_nfail + ra->ra_nok))/2; 178 ra->ra_nfail = ra->ra_nok = 0; 179 180 /* 181 * A node is eligible for its rate to be raised every 1/10 to 10 182 * seconds, more eligible in proportion to recent packet rates. 183 */ 184 interval = MAX(10*1000, 10*1000 / MAX(1, 10 * ra->ra_pktrate)); 185 ra->ra_raise_interval = msecs_to_ticks(interval); 186 } 187 188 static void 189 rssadapt_node_init(struct ieee80211_node *ni) 190 { 191 struct ieee80211_rssadapt_node *ra; 192 struct ieee80211vap *vap = ni->ni_vap; 193 struct ieee80211_rssadapt *rsa = vap->iv_rs; 194 const struct ieee80211_rateset *rs = &ni->ni_rates; 195 196 if (ni->ni_rctls == NULL) { 197 ni->ni_rctls = ra = 198 IEEE80211_MALLOC(sizeof(struct ieee80211_rssadapt_node), 199 M_80211_RATECTL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 200 if (ra == NULL) { 201 if_printf(vap->iv_ifp, "couldn't alloc per-node ratectl " 202 "structure\n"); 203 return; 204 } 205 } else 206 ra = ni->ni_rctls; 207 ra->ra_rs = rsa; 208 ra->ra_rates = *rs; 209 rssadapt_updatestats(ra); 210 211 /* pick initial rate */ 212 for (ra->ra_rix = rs->rs_nrates - 1; 213 ra->ra_rix > 0 && (rs->rs_rates[ra->ra_rix] & IEEE80211_RATE_VAL) > 72; 214 ra->ra_rix--) 215 ; 216 ni->ni_txrate = rs->rs_rates[ra->ra_rix] & IEEE80211_RATE_VAL; 217 ra->ra_ticks = ticks; 218 219 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 220 "RSSADAPT initial rate %d", ni->ni_txrate); 221 } 222 223 static void 224 rssadapt_node_deinit(struct ieee80211_node *ni) 225 { 226 227 IEEE80211_FREE(ni->ni_rctls, M_80211_RATECTL); 228 } 229 230 static __inline int 231 bucket(int pktlen) 232 { 233 int i, top, thridx; 234 235 for (i = 0, top = IEEE80211_RSSADAPT_BKT0; 236 i < IEEE80211_RSSADAPT_BKTS; 237 i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) { 238 thridx = i; 239 if (pktlen <= top) 240 break; 241 } 242 return thridx; 243 } 244 245 static int 246 rssadapt_rate(struct ieee80211_node *ni, void *arg __unused, uint32_t iarg) 247 { 248 struct ieee80211_rssadapt_node *ra = ni->ni_rctls; 249 u_int pktlen = iarg; 250 const struct ieee80211_rateset *rs = &ra->ra_rates; 251 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 252 int rix, rssi; 253 254 if ((ticks - ra->ra_ticks) > ra->ra_rs->interval) { 255 rssadapt_updatestats(ra); 256 ra->ra_ticks = ticks; 257 } 258 259 thrs = &ra->ra_rate_thresh[bucket(pktlen)]; 260 261 /* XXX this is average rssi, should be using last value */ 262 rssi = ni->ni_ic->ic_node_getrssi(ni); 263 for (rix = rs->rs_nrates-1; rix >= 0; rix--) 264 if ((*thrs)[rix] < (rssi << 8)) 265 break; 266 if (rix != ra->ra_rix) { 267 /* update public rate */ 268 ni->ni_txrate = ni->ni_rates.rs_rates[rix] & IEEE80211_RATE_VAL; 269 ra->ra_rix = rix; 270 271 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 272 "RSSADAPT new rate %d (pktlen %d rssi %d)", 273 ni->ni_txrate, pktlen, rssi); 274 } 275 return rix; 276 } 277 278 /* 279 * Adapt the data rate to suit the conditions. When a transmitted 280 * packet is dropped after RAL_RSSADAPT_RETRY_LIMIT retransmissions, 281 * raise the RSS threshold for transmitting packets of similar length at 282 * the same data rate. 283 */ 284 static void 285 rssadapt_lower_rate(struct ieee80211_rssadapt_node *ra, int pktlen, int rssi) 286 { 287 uint16_t last_thr; 288 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 289 u_int rix; 290 291 thrs = &ra->ra_rate_thresh[bucket(pktlen)]; 292 293 rix = ra->ra_rix; 294 last_thr = (*thrs)[rix]; 295 (*thrs)[rix] = interpolate(master_expavgctl.rc_thresh, 296 last_thr, (rssi << 8)); 297 298 IEEE80211_DPRINTF(ra->ra_rs->vap, IEEE80211_MSG_RATECTL, 299 "RSSADAPT lower threshold for rate %d (last_thr %d new thr %d rssi %d)\n", 300 ra->ra_rates.rs_rates[rix + 1] & IEEE80211_RATE_VAL, 301 last_thr, (*thrs)[rix], rssi); 302 } 303 304 static void 305 rssadapt_raise_rate(struct ieee80211_rssadapt_node *ra, int pktlen, int rssi) 306 { 307 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 308 uint16_t newthr, oldthr; 309 int rix; 310 311 thrs = &ra->ra_rate_thresh[bucket(pktlen)]; 312 313 rix = ra->ra_rix; 314 if ((*thrs)[rix + 1] > (*thrs)[rix]) { 315 oldthr = (*thrs)[rix + 1]; 316 if ((*thrs)[rix] == 0) 317 newthr = (rssi << 8); 318 else 319 newthr = (*thrs)[rix]; 320 (*thrs)[rix + 1] = interpolate(master_expavgctl.rc_decay, 321 oldthr, newthr); 322 323 IEEE80211_DPRINTF(ra->ra_rs->vap, IEEE80211_MSG_RATECTL, 324 "RSSADAPT raise threshold for rate %d (oldthr %d newthr %d rssi %d)\n", 325 ra->ra_rates.rs_rates[rix + 1] & IEEE80211_RATE_VAL, 326 oldthr, newthr, rssi); 327 328 ra->ra_last_raise = ticks; 329 } 330 } 331 332 static void 333 rssadapt_tx_complete(const struct ieee80211_node *ni, 334 const struct ieee80211_ratectl_tx_status *status) 335 { 336 struct ieee80211_rssadapt_node *ra = ni->ni_rctls; 337 int pktlen, rssi; 338 339 if ((status->flags & 340 (IEEE80211_RATECTL_STATUS_PKTLEN|IEEE80211_RATECTL_STATUS_RSSI)) != 341 (IEEE80211_RATECTL_STATUS_PKTLEN|IEEE80211_RATECTL_STATUS_RSSI)) 342 return; 343 344 pktlen = status->pktlen; 345 rssi = status->rssi; 346 347 if (status->status == IEEE80211_RATECTL_TX_SUCCESS) { 348 ra->ra_nok++; 349 if ((ra->ra_rix + 1) < ra->ra_rates.rs_nrates && 350 (ticks - ra->ra_last_raise) >= ra->ra_raise_interval) 351 rssadapt_raise_rate(ra, pktlen, rssi); 352 } else { 353 ra->ra_nfail++; 354 rssadapt_lower_rate(ra, pktlen, rssi); 355 } 356 } 357 358 #ifdef notyet 359 static int 360 rssadapt_sysctl_interval(SYSCTL_HANDLER_ARGS) 361 { 362 struct ieee80211vap *vap = arg1; 363 struct ieee80211_rssadapt *rs = vap->iv_rs; 364 int msecs = ticks_to_msecs(rs->interval); 365 int error; 366 367 error = sysctl_handle_int(oidp, &msecs, 0, req); 368 if (error || !req->newptr) 369 return error; 370 rssadapt_setinterval(vap, msecs); 371 return 0; 372 } 373 #endif 374 375 static void 376 rssadapt_sysctlattach(struct ieee80211vap *vap, 377 struct sysctl_ctx_list *ctx, struct sysctl_oid *tree) 378 { 379 #ifdef notyet 380 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 381 "rssadapt_rate_interval", CTLTYPE_INT | CTLFLAG_RW, vap, 382 0, rssadapt_sysctl_interval, "I", "rssadapt operation interval (ms)"); 383 #endif 384 } 385
Indexes created Tue Sep 30 20:09:53 GMT 2025