ieee80211_rssadapt.c revision 1.21.16.5
1 /* $NetBSD: ieee80211_rssadapt.c,v 1.21.16.5 2019/06/10 22:09:46 christos 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 <sys/cdefs.h> 36 #ifdef __NetBSD__ 37 __KERNEL_RCSID(0, "$NetBSD: ieee80211_rssadapt.c,v 1.21.16.5 2019/06/10 22:09:46 christos Exp $"); 38 #endif 39 40 #ifdef _KERNEL_OPT 41 #include "opt_wlan.h" 42 #endif 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/malloc.h> 48 #include <sys/module.h> 49 #ifdef __NetBSD__ 50 /* Why doesn't FreeBSD have this? */ 51 #include <sys/sbuf.h> 52 #endif 53 #include <sys/socket.h> 54 #include <sys/sysctl.h> 55 56 #include <net/if.h> 57 #ifdef __FreeBSD__ 58 #include <net/if_var.h> 59 #endif 60 #include <net/if_media.h> 61 #ifdef __FreeBSD__ 62 #include <net/ethernet.h> 63 #endif 64 #ifdef __NetBSD__ 65 #include <net/route.h> 66 #endif 67 68 #include <net80211/ieee80211_var.h> 69 #include <net80211/ieee80211_rssadapt.h> 70 #include <net80211/ieee80211_ratectl.h> 71 72 #ifdef __NetBSD__ 73 #undef KASSERT 74 #define KASSERT(__cond, __complaint) FBSDKASSERT(__cond, __complaint) 75 #endif 76 77 struct rssadapt_expavgctl { 78 /* RSS threshold decay. */ 79 u_int rc_decay_denom; 80 u_int rc_decay_old; 81 /* RSS threshold update. */ 82 u_int rc_thresh_denom; 83 u_int rc_thresh_old; 84 /* RSS average update. */ 85 u_int rc_avgrssi_denom; 86 u_int rc_avgrssi_old; 87 }; 88 89 static struct rssadapt_expavgctl master_expavgctl = { 90 .rc_decay_denom = 16, 91 .rc_decay_old = 15, 92 .rc_thresh_denom = 8, 93 .rc_thresh_old = 4, 94 .rc_avgrssi_denom = 8, 95 .rc_avgrssi_old = 4 96 }; 97 98 #ifdef interpolate 99 #undef interpolate 100 #endif 101 #define interpolate(parm, old, new) ((parm##_old * (old) + \ 102 (parm##_denom - parm##_old) * (new)) / \ 103 parm##_denom) 104 105 static void rssadapt_setinterval(const struct ieee80211vap *, int); 106 static void rssadapt_init(struct ieee80211vap *); 107 static void rssadapt_deinit(struct ieee80211vap *); 108 static void rssadapt_updatestats(struct ieee80211_rssadapt_node *); 109 static void rssadapt_node_init(struct ieee80211_node *); 110 static void rssadapt_node_deinit(struct ieee80211_node *); 111 static int rssadapt_rate(struct ieee80211_node *, void *, uint32_t); 112 static void rssadapt_lower_rate(struct ieee80211_rssadapt_node *, int, int); 113 static void rssadapt_raise_rate(struct ieee80211_rssadapt_node *, 114 int, int); 115 static void rssadapt_tx_complete(const struct ieee80211_node *, 116 const struct ieee80211_ratectl_tx_status *); 117 #ifdef notyet 118 static void rssadapt_sysctlattach(struct ieee80211vap *, 119 struct sysctl_ctx_list *, struct sysctl_oid *); 120 #endif 121 122 /* number of references from net80211 layer */ 123 static int nrefs = 0; 124 125 #if __FreeBSD__ 126 static const struct ieee80211_ratectl rssadapt = { 127 #elif __NetBSD__ 128 const struct ieee80211_ratectl ratectl_rssadapt = { 129 #endif 130 .ir_name = "rssadapt", 131 .ir_attach = NULL, 132 .ir_detach = NULL, 133 .ir_init = rssadapt_init, 134 .ir_deinit = rssadapt_deinit, 135 .ir_node_init = rssadapt_node_init, 136 .ir_node_deinit = rssadapt_node_deinit, 137 .ir_rate = rssadapt_rate, 138 .ir_tx_complete = rssadapt_tx_complete, 139 .ir_tx_update = NULL, 140 .ir_setinterval = rssadapt_setinterval, 141 }; 142 #if __FreeBSD__ 143 IEEE80211_RATECTL_MODULE(rssadapt, 1); 144 IEEE80211_RATECTL_ALG(rssadapt, IEEE80211_RATECTL_RSSADAPT, rssadapt); 145 #endif 146 147 static void 148 rssadapt_setinterval(const struct ieee80211vap *vap, int msecs) 149 { 150 struct ieee80211_rssadapt *rs = vap->iv_rs; 151 int t; 152 153 if (msecs < 100) 154 msecs = 100; 155 t = msecs_to_ticks(msecs); 156 rs->interval = (t < 1) ? 1 : t; 157 } 158 159 static void 160 rssadapt_init(struct ieee80211vap *vap) 161 { 162 struct ieee80211_rssadapt *rs; 163 164 KASSERT(vap->iv_rs == NULL, ("%s: iv_rs already initialized", 165 __func__)); 166 167 nrefs++; /* XXX locking */ 168 vap->iv_rs = rs = IEEE80211_MALLOC(sizeof(struct ieee80211_rssadapt), 169 M_80211_RATECTL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 170 if (rs == NULL) { 171 if_printf(vap->iv_ifp, "couldn't alloc ratectl structure\n"); 172 return; 173 } 174 rs->vap = vap; 175 rssadapt_setinterval(vap, 500 /* msecs */); 176 #ifdef notyet 177 rssadapt_sysctlattach(vap, vap->iv_sysctl, vap->iv_oid); 178 #endif 179 } 180 181 static void 182 rssadapt_deinit(struct ieee80211vap *vap) 183 { 184 IEEE80211_FREE(vap->iv_rs, M_80211_RATECTL); 185 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 186 nrefs--; /* XXX locking */ 187 } 188 189 static void 190 rssadapt_updatestats(struct ieee80211_rssadapt_node *ra) 191 { 192 long interval; 193 194 ra->ra_pktrate = (ra->ra_pktrate + 10*(ra->ra_nfail + ra->ra_nok))/2; 195 ra->ra_nfail = ra->ra_nok = 0; 196 197 /* 198 * A node is eligible for its rate to be raised every 1/10 to 10 199 * seconds, more eligible in proportion to recent packet rates. 200 */ 201 interval = MAX(10*1000, 10*1000 / MAX(1, 10 * ra->ra_pktrate)); 202 ra->ra_raise_interval = msecs_to_ticks(interval); 203 } 204 205 static void 206 rssadapt_node_init(struct ieee80211_node *ni) 207 { 208 struct ieee80211_rssadapt_node *ra; 209 struct ieee80211vap *vap = ni->ni_vap; 210 struct ieee80211_rssadapt *rsa = vap->iv_rs; 211 const struct ieee80211_rateset *rs = &ni->ni_rates; 212 213 if (ni->ni_rctls == NULL) { 214 ni->ni_rctls = ra = 215 IEEE80211_MALLOC(sizeof(struct ieee80211_rssadapt_node), 216 M_80211_RATECTL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 217 if (ra == NULL) { 218 if_printf(vap->iv_ifp, "couldn't alloc per-node ratectl " 219 "structure\n"); 220 return; 221 } 222 } else 223 ra = ni->ni_rctls; 224 ra->ra_rs = rsa; 225 ra->ra_rates = *rs; 226 rssadapt_updatestats(ra); 227 228 /* pick initial rate */ 229 for (ra->ra_rix = rs->rs_nrates - 1; 230 ra->ra_rix > 0 && (rs->rs_rates[ra->ra_rix] & IEEE80211_RATE_VAL) > 72; 231 ra->ra_rix--) 232 ; 233 ni->ni_txrate = rs->rs_rates[ra->ra_rix] & IEEE80211_RATE_VAL; 234 ra->ra_ticks = ticks; 235 236 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 237 "RSSADAPT initial rate %d", ni->ni_txrate); 238 } 239 240 static void 241 rssadapt_node_deinit(struct ieee80211_node *ni) 242 { 243 244 IEEE80211_FREE(ni->ni_rctls, M_80211_RATECTL); 245 } 246 247 static __inline int 248 bucket(int pktlen) 249 { 250 int i, top, thridx; 251 252 for (i = 0, top = IEEE80211_RSSADAPT_BKT0; 253 i < IEEE80211_RSSADAPT_BKTS; 254 i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) { 255 thridx = i; 256 if (pktlen <= top) 257 break; 258 } 259 return thridx; 260 } 261 262 static int 263 rssadapt_rate(struct ieee80211_node *ni, void *arg __unused, uint32_t iarg) 264 { 265 struct ieee80211_rssadapt_node *ra = ni->ni_rctls; 266 u_int pktlen = iarg; 267 const struct ieee80211_rateset *rs = &ra->ra_rates; 268 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 269 int rix, rssi; 270 271 if ((ticks - ra->ra_ticks) > ra->ra_rs->interval) { 272 rssadapt_updatestats(ra); 273 ra->ra_ticks = ticks; 274 } 275 276 thrs = &ra->ra_rate_thresh[bucket(pktlen)]; 277 278 /* XXX this is average rssi, should be using last value */ 279 rssi = ni->ni_ic->ic_node_getrssi(ni); 280 for (rix = rs->rs_nrates-1; rix >= 0; rix--) 281 if ((*thrs)[rix] < (rssi << 8)) 282 break; 283 if (rix != ra->ra_rix) { 284 /* update public rate */ 285 ni->ni_txrate = ni->ni_rates.rs_rates[rix] & IEEE80211_RATE_VAL; 286 ra->ra_rix = rix; 287 288 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni, 289 "RSSADAPT new rate %d (pktlen %d rssi %d)", 290 ni->ni_txrate, pktlen, rssi); 291 } 292 return rix; 293 } 294 295 /* 296 * Adapt the data rate to suit the conditions. When a transmitted 297 * packet is dropped after RAL_RSSADAPT_RETRY_LIMIT retransmissions, 298 * raise the RSS threshold for transmitting packets of similar length at 299 * the same data rate. 300 */ 301 static void 302 rssadapt_lower_rate(struct ieee80211_rssadapt_node *ra, int pktlen, int rssi) 303 { 304 uint16_t last_thr; 305 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 306 u_int rix; 307 308 thrs = &ra->ra_rate_thresh[bucket(pktlen)]; 309 310 rix = ra->ra_rix; 311 last_thr = (*thrs)[rix]; 312 (*thrs)[rix] = interpolate(master_expavgctl.rc_thresh, 313 last_thr, (rssi << 8)); 314 315 IEEE80211_DPRINTF(ra->ra_rs->vap, IEEE80211_MSG_RATECTL, 316 "RSSADAPT lower threshold for rate %d (last_thr %d new thr %d rssi %d)\n", 317 ra->ra_rates.rs_rates[rix + 1] & IEEE80211_RATE_VAL, 318 last_thr, (*thrs)[rix], rssi); 319 } 320 321 static void 322 rssadapt_raise_rate(struct ieee80211_rssadapt_node *ra, int pktlen, int rssi) 323 { 324 uint16_t (*thrs)[IEEE80211_RATE_SIZE]; 325 uint16_t newthr, oldthr; 326 int rix; 327 328 thrs = &ra->ra_rate_thresh[bucket(pktlen)]; 329 330 rix = ra->ra_rix; 331 if ((*thrs)[rix + 1] > (*thrs)[rix]) { 332 oldthr = (*thrs)[rix + 1]; 333 if ((*thrs)[rix] == 0) 334 newthr = (rssi << 8); 335 else 336 newthr = (*thrs)[rix]; 337 (*thrs)[rix + 1] = interpolate(master_expavgctl.rc_decay, 338 oldthr, newthr); 339 340 IEEE80211_DPRINTF(ra->ra_rs->vap, IEEE80211_MSG_RATECTL, 341 "RSSADAPT raise threshold for rate %d (oldthr %d newthr %d rssi %d)\n", 342 ra->ra_rates.rs_rates[rix + 1] & IEEE80211_RATE_VAL, 343 oldthr, newthr, rssi); 344 345 ra->ra_last_raise = ticks; 346 } 347 } 348 349 static void 350 rssadapt_tx_complete(const struct ieee80211_node *ni, 351 const struct ieee80211_ratectl_tx_status *status) 352 { 353 struct ieee80211_rssadapt_node *ra = ni->ni_rctls; 354 int pktlen, rssi; 355 356 if ((status->flags & 357 (IEEE80211_RATECTL_STATUS_PKTLEN|IEEE80211_RATECTL_STATUS_RSSI)) != 358 (IEEE80211_RATECTL_STATUS_PKTLEN|IEEE80211_RATECTL_STATUS_RSSI)) 359 return; 360 361 pktlen = status->pktlen; 362 rssi = status->rssi; 363 364 if (status->status == IEEE80211_RATECTL_TX_SUCCESS) { 365 ra->ra_nok++; 366 if ((ra->ra_rix + 1) < ra->ra_rates.rs_nrates && 367 (ticks - ra->ra_last_raise) >= ra->ra_raise_interval) 368 rssadapt_raise_rate(ra, pktlen, rssi); 369 } else { 370 ra->ra_nfail++; 371 rssadapt_lower_rate(ra, pktlen, rssi); 372 } 373 } 374 375 #ifdef notyet 376 static int 377 rssadapt_sysctl_interval(SYSCTL_HANDLER_ARGS) 378 { 379 struct ieee80211vap *vap = arg1; 380 struct ieee80211_rssadapt *rs = vap->iv_rs; 381 int msecs = ticks_to_msecs(rs->interval); 382 int error; 383 384 error = sysctl_handle_int(oidp, &msecs, 0, req); 385 if (error || !req->newptr) 386 return error; 387 rssadapt_setinterval(vap, msecs); 388 return 0; 389 } 390 391 static void 392 rssadapt_sysctlattach(struct ieee80211vap *vap, 393 struct sysctl_ctx_list *ctx, struct sysctl_oid *tree) 394 { 395 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 396 "rssadapt_rate_interval", CTLTYPE_INT | CTLFLAG_RW, vap, 397 0, rssadapt_sysctl_interval, "I", "rssadapt operation interval (ms)"); 398 } 399 #endif 400
Indexes created Tue Sep 30 20:09:53 GMT 2025