ieee80211_rssadapt.c revision 1.15
1 /* $NetBSD: ieee80211_rssadapt.c,v 1.15 2008/06/24 10:33:46 gmcgarry Exp $ */ 2 /*- 3 * Copyright (c) 2003, 2004 David Young. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or 6 * without modification, are permitted provided that the following 7 * conditions are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following 12 * disclaimer in the documentation and/or other materials provided 13 * with the distribution. 14 * 3. The name of David Young may not be used to endorse or promote 15 * products derived from this software without specific prior 16 * written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY David Young ``AS IS'' AND ANY 19 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 20 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 21 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL David 22 * Young BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 23 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 24 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 26 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 27 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 29 * OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifdef __NetBSD__ 34 __KERNEL_RCSID(0, "$NetBSD: ieee80211_rssadapt.c,v 1.15 2008/06/24 10:33:46 gmcgarry Exp $"); 35 #endif 36 37 #include <sys/param.h> 38 #include <sys/types.h> 39 #include <sys/kernel.h> /* for hz */ 40 #include <sys/sysctl.h> 41 42 #include <net/if.h> 43 #include <net/if_media.h> 44 #include <net/if_ether.h> 45 46 #include <net80211/ieee80211_netbsd.h> 47 #include <net80211/ieee80211_var.h> 48 #include <net80211/ieee80211.h> 49 #include <net80211/ieee80211_rssadapt.h> 50 51 #ifdef interpolate 52 #undef interpolate 53 #endif 54 #define interpolate(parm, old, new) ((parm##_old * (old) + \ 55 (parm##_denom - parm##_old) * (new)) / \ 56 parm##_denom) 57 58 #ifdef IEEE80211_DEBUG 59 static struct timeval lastrateadapt; /* time of last rate adaptation msg */ 60 static int currssadaptps = 0; /* rate-adaptation msgs this second */ 61 static int ieee80211_adaptrate = 4; /* rate-adaptation max msgs/sec */ 62 63 #define RSSADAPT_DO_PRINT() \ 64 ((ieee80211_rssadapt_debug > 0) && \ 65 ppsratecheck(&lastrateadapt, &currssadaptps, ieee80211_adaptrate)) 66 #define RSSADAPT_PRINTF(X) \ 67 if (RSSADAPT_DO_PRINT()) \ 68 printf X 69 70 int ieee80211_rssadapt_debug = 0; 71 72 #else 73 #define RSSADAPT_DO_PRINT() (0) 74 #define RSSADAPT_PRINTF(X) 75 #endif 76 77 static struct ieee80211_rssadapt_expavgctl master_expavgctl = { 78 .rc_decay_denom = 16, 79 .rc_decay_old = 15, 80 .rc_thresh_denom = 8, 81 .rc_thresh_old = 4, 82 .rc_avgrssi_denom = 8, 83 .rc_avgrssi_old = 4 84 }; 85 86 #ifdef __NetBSD__ 87 #ifdef IEEE80211_DEBUG 88 /* TBD factor with sysctl_ath_verify, sysctl_ieee80211_verify. */ 89 static int 90 sysctl_ieee80211_rssadapt_debug(SYSCTLFN_ARGS) 91 { 92 int error, t; 93 struct sysctlnode node; 94 95 node = *rnode; 96 t = *(int*)rnode->sysctl_data; 97 node.sysctl_data = &t; 98 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 99 if (error || newp == NULL) 100 return (error); 101 102 if (t < 0 || t > 2) 103 return (EINVAL); 104 *(int*)rnode->sysctl_data = t; 105 106 return (0); 107 } 108 #endif /* IEEE80211_DEBUG */ 109 110 /* TBD factor with sysctl_ath_verify, sysctl_ieee80211_verify. */ 111 static int 112 sysctl_ieee80211_rssadapt_expavgctl(SYSCTLFN_ARGS) 113 { 114 struct ieee80211_rssadapt_expavgctl rc; 115 int error; 116 struct sysctlnode node; 117 118 node = *rnode; 119 rc = *(struct ieee80211_rssadapt_expavgctl *)rnode->sysctl_data; 120 node.sysctl_data = &rc; 121 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 122 if (error || newp == NULL) 123 return (error); 124 125 if (/* rc.rc_decay_old < 0 || */ 126 rc.rc_decay_denom < rc.rc_decay_old) 127 return (EINVAL); 128 129 if (/* rc.rc_thresh_old < 0 || */ 130 rc.rc_thresh_denom < rc.rc_thresh_old) 131 return (EINVAL); 132 133 if (/* rc.rc_avgrssi_old < 0 || */ 134 rc.rc_avgrssi_denom < rc.rc_avgrssi_old) 135 return (EINVAL); 136 137 *(struct ieee80211_rssadapt_expavgctl *)rnode->sysctl_data = rc; 138 139 return (0); 140 } 141 142 /* 143 * Setup sysctl(3) MIB, net.ieee80211.* 144 * 145 * TBD condition CTLFLAG_PERMANENT on being an LKM or not 146 */ 147 SYSCTL_SETUP(sysctl_ieee80211_rssadapt, 148 "sysctl ieee80211 rssadapt subtree setup") 149 { 150 int rc; 151 const struct sysctlnode *node; 152 153 if ((rc = sysctl_createv(clog, 0, NULL, &node, 154 CTLFLAG_PERMANENT, CTLTYPE_NODE, "net", NULL, 155 NULL, 0, NULL, 0, CTL_NET, CTL_EOL)) != 0) 156 goto err; 157 158 if ((rc = sysctl_createv(clog, 0, &node, &node, 159 CTLFLAG_PERMANENT, CTLTYPE_NODE, "link", NULL, 160 NULL, 0, NULL, 0, PF_LINK, CTL_EOL)) != 0) 161 goto err; 162 163 if ((rc = sysctl_createv(clog, 0, &node, &node, 164 CTLFLAG_PERMANENT, CTLTYPE_NODE, "ieee80211", NULL, 165 NULL, 0, NULL, 0, CTL_CREATE, CTL_EOL)) != 0) 166 goto err; 167 168 if ((rc = sysctl_createv(clog, 0, &node, &node, 169 CTLFLAG_PERMANENT, CTLTYPE_NODE, "rssadapt", 170 SYSCTL_DESCR("Received Signal Strength adaptation controls"), 171 NULL, 0, NULL, 0, CTL_CREATE, CTL_EOL)) != 0) 172 goto err; 173 174 #ifdef IEEE80211_DEBUG 175 /* control debugging printfs */ 176 if ((rc = sysctl_createv(clog, 0, &node, NULL, 177 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "debug", 178 SYSCTL_DESCR("Enable RSS adaptation debugging output"), 179 sysctl_ieee80211_rssadapt_debug, 0, &ieee80211_rssadapt_debug, 0, 180 CTL_CREATE, CTL_EOL)) != 0) 181 goto err; 182 #endif /* IEEE80211_DEBUG */ 183 184 /* control rate of decay for exponential averages */ 185 if ((rc = sysctl_createv(clog, 0, &node, NULL, 186 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_STRUCT, 187 "expavgctl", SYSCTL_DESCR("RSS exponential averaging control"), 188 sysctl_ieee80211_rssadapt_expavgctl, 0, 189 &master_expavgctl, sizeof(master_expavgctl), CTL_CREATE, 190 CTL_EOL)) != 0) 191 goto err; 192 193 return; 194 err: 195 printf("%s: sysctl_createv failed (rc = %d)\n", __func__, rc); 196 } 197 #endif /* __NetBSD__ */ 198 199 int 200 ieee80211_rssadapt_choose(struct ieee80211_rssadapt *ra, 201 struct ieee80211_rateset *rs, struct ieee80211_frame *wh, u_int len, 202 int fixed_rate, const char *dvname, int do_not_adapt) 203 { 204 u_int16_t (*thrs)[IEEE80211_RATE_SIZE]; 205 int flags = 0, i, rateidx = 0, thridx, top; 206 207 if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL) 208 flags |= IEEE80211_RATE_BASIC; 209 210 for (i = 0, top = IEEE80211_RSSADAPT_BKT0; 211 i < IEEE80211_RSSADAPT_BKTS; 212 i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) { 213 thridx = i; 214 if (len <= top) 215 break; 216 } 217 218 thrs = &ra->ra_rate_thresh[thridx]; 219 220 if (fixed_rate != -1) { 221 if ((rs->rs_rates[fixed_rate] & flags) == flags) { 222 rateidx = fixed_rate; 223 goto out; 224 } 225 flags |= IEEE80211_RATE_BASIC; 226 i = fixed_rate; 227 } else 228 i = rs->rs_nrates; 229 230 while (--i >= 0) { 231 rateidx = i; 232 if ((rs->rs_rates[i] & flags) != flags) 233 continue; 234 if (do_not_adapt) 235 break; 236 if ((*thrs)[i] < ra->ra_avg_rssi) 237 break; 238 } 239 240 out: 241 #ifdef IEEE80211_DEBUG 242 if (ieee80211_rssadapt_debug && dvname != NULL) { 243 printf("%s: dst %s threshold[%d, %d.%d] %d < %d\n", 244 dvname, ether_sprintf(wh->i_addr1), len, 245 (rs->rs_rates[rateidx] & IEEE80211_RATE_VAL) / 2, 246 (rs->rs_rates[rateidx] & IEEE80211_RATE_VAL) * 5 % 10, 247 (*thrs)[rateidx], ra->ra_avg_rssi); 248 } 249 #endif /* IEEE80211_DEBUG */ 250 return rateidx; 251 } 252 253 void 254 ieee80211_rssadapt_updatestats(struct ieee80211_rssadapt *ra) 255 { 256 long interval; 257 258 ra->ra_pktrate = 259 (ra->ra_pktrate + 10 * (ra->ra_nfail + ra->ra_nok)) / 2; 260 ra->ra_nfail = ra->ra_nok = 0; 261 262 /* a node is eligible for its rate to be raised every 1/10 to 10 263 * seconds, more eligible in proportion to recent packet rates. 264 */ 265 interval = MAX(100000, 10000000 / MAX(1, 10 * ra->ra_pktrate)); 266 ra->ra_raise_interval.tv_sec = interval / (1000 * 1000); 267 ra->ra_raise_interval.tv_usec = interval % (1000 * 1000); 268 } 269 270 void 271 ieee80211_rssadapt_input(struct ieee80211com *ic, struct ieee80211_node *ni, 272 struct ieee80211_rssadapt *ra, int rssi) 273 { 274 #ifdef IEEE80211_DEBUG 275 int last_avg_rssi = ra->ra_avg_rssi; 276 #endif 277 278 ra->ra_avg_rssi = interpolate(master_expavgctl.rc_avgrssi, 279 ra->ra_avg_rssi, (rssi << 8)); 280 281 RSSADAPT_PRINTF(("%s: src %s rssi %d avg %d -> %d\n", 282 ic->ic_ifp->if_xname, ether_sprintf(ni->ni_macaddr), 283 rssi, last_avg_rssi, ra->ra_avg_rssi)); 284 } 285 286 /* 287 * Adapt the data rate to suit the conditions. When a transmitted 288 * packet is dropped after IEEE80211_RSSADAPT_RETRY_LIMIT retransmissions, 289 * raise the RSS threshold for transmitting packets of similar length at 290 * the same data rate. 291 */ 292 void 293 ieee80211_rssadapt_lower_rate(struct ieee80211com *ic, 294 struct ieee80211_node *ni, struct ieee80211_rssadapt *ra, 295 struct ieee80211_rssdesc *id) 296 { 297 struct ieee80211_rateset *rs = &ni->ni_rates; 298 u_int16_t last_thr; 299 u_int i, thridx, top; 300 301 ra->ra_nfail++; 302 303 if (id->id_rateidx >= rs->rs_nrates) { 304 RSSADAPT_PRINTF(("ieee80211_rssadapt_lower_rate: " 305 "%s rate #%d > #%d out of bounds\n", 306 ether_sprintf(ni->ni_macaddr), id->id_rateidx, 307 rs->rs_nrates - 1)); 308 return; 309 } 310 311 for (i = 0, top = IEEE80211_RSSADAPT_BKT0; 312 i < IEEE80211_RSSADAPT_BKTS; 313 i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) { 314 thridx = i; 315 if (id->id_len <= top) 316 break; 317 } 318 319 last_thr = ra->ra_rate_thresh[thridx][id->id_rateidx]; 320 ra->ra_rate_thresh[thridx][id->id_rateidx] = 321 interpolate(master_expavgctl.rc_thresh, last_thr, 322 (id->id_rssi << 8)); 323 324 RSSADAPT_PRINTF(("%s: dst %s rssi %d threshold[%d, %d.%d] %d -> %d\n", 325 ic->ic_ifp->if_xname, ether_sprintf(ni->ni_macaddr), 326 id->id_rssi, id->id_len, 327 (rs->rs_rates[id->id_rateidx] & IEEE80211_RATE_VAL) / 2, 328 (rs->rs_rates[id->id_rateidx] & IEEE80211_RATE_VAL) * 5 % 10, 329 last_thr, ra->ra_rate_thresh[thridx][id->id_rateidx])); 330 } 331 332 void 333 ieee80211_rssadapt_raise_rate(struct ieee80211com *ic, 334 struct ieee80211_rssadapt *ra, struct ieee80211_rssdesc *id) 335 { 336 u_int16_t (*thrs)[IEEE80211_RATE_SIZE], newthr, oldthr; 337 struct ieee80211_node *ni = id->id_node; 338 struct ieee80211_rateset *rs = &ni->ni_rates; 339 int i, rate, top; 340 #ifdef IEEE80211_DEBUG 341 int j; 342 #endif 343 344 ra->ra_nok++; 345 346 if (!ratecheck(&ra->ra_last_raise, &ra->ra_raise_interval)) 347 return; 348 349 for (i = 0, top = IEEE80211_RSSADAPT_BKT0; 350 i < IEEE80211_RSSADAPT_BKTS; 351 i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) { 352 thrs = &ra->ra_rate_thresh[i]; 353 if (id->id_len <= top) 354 break; 355 } 356 357 if (id->id_rateidx + 1 < rs->rs_nrates && 358 (*thrs)[id->id_rateidx + 1] > (*thrs)[id->id_rateidx]) { 359 rate = (rs->rs_rates[id->id_rateidx + 1] & IEEE80211_RATE_VAL); 360 361 RSSADAPT_PRINTF(("%s: threshold[%d, %d.%d] decay %d ", 362 ic->ic_ifp->if_xname, 363 IEEE80211_RSSADAPT_BKT0 << (IEEE80211_RSSADAPT_BKTPOWER* i), 364 rate / 2, rate * 5 % 10, (*thrs)[id->id_rateidx + 1])); 365 oldthr = (*thrs)[id->id_rateidx + 1]; 366 if ((*thrs)[id->id_rateidx] == 0) 367 newthr = ra->ra_avg_rssi; 368 else 369 newthr = (*thrs)[id->id_rateidx]; 370 (*thrs)[id->id_rateidx + 1] = 371 interpolate(master_expavgctl.rc_decay, oldthr, newthr); 372 373 RSSADAPT_PRINTF(("-> %d\n", (*thrs)[id->id_rateidx + 1])); 374 } 375 376 #ifdef IEEE80211_DEBUG 377 if (RSSADAPT_DO_PRINT()) { 378 printf("%s: dst %s thresholds\n", ic->ic_ifp->if_xname, 379 ether_sprintf(ni->ni_macaddr)); 380 for (i = 0; i < IEEE80211_RSSADAPT_BKTS; i++) { 381 printf("%d-byte", IEEE80211_RSSADAPT_BKT0 << (IEEE80211_RSSADAPT_BKTPOWER * i)); 382 for (j = 0; j < rs->rs_nrates; j++) { 383 rate = (rs->rs_rates[j] & IEEE80211_RATE_VAL); 384 printf(", T[%d.%d] = %d", rate / 2, 385 rate * 5 % 10, ra->ra_rate_thresh[i][j]); 386 } 387 printf("\n"); 388 } 389 } 390 #endif /* IEEE80211_DEBUG */ 391 } 392
Indexes created Mon Sep 22 21:09:42 GMT 2025