ieee80211_rssadapt.c revision 1.7
1 /* $NetBSD: ieee80211_rssadapt.c,v 1.7 2004/05/25 04:33:59 atatat 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/param.h> 33 #include <sys/types.h> 34 #include <sys/kernel.h> /* for hz */ 35 #include <sys/sysctl.h> 36 37 #include <net/if.h> 38 #include <net/if_media.h> 39 #include <net/if_ether.h> 40 41 #include <net80211/ieee80211_var.h> 42 #include <net80211/ieee80211.h> 43 #include <net80211/ieee80211_compat.h> 44 #include <net80211/ieee80211_rssadapt.h> 45 46 #ifdef interpolate 47 #undef interpolate 48 #endif 49 #define interpolate(parm, old, new) ((parm##_old * (old) + \ 50 (parm##_denom - parm##_old) * (new)) / \ 51 parm##_denom) 52 53 #ifdef IEEE80211_DEBUG 54 static struct timeval lastrateadapt; /* time of last rate adaptation msg */ 55 static int currssadaptps = 0; /* rate-adaptation msgs this second */ 56 static int ieee80211_adaptrate = 4; /* rate-adaptation max msgs/sec */ 57 58 #define RSSADAPT_DO_PRINT() \ 59 ((ieee80211_rssadapt_debug > 0) && \ 60 ppsratecheck(&lastrateadapt, &currssadaptps, ieee80211_adaptrate)) 61 #define RSSADAPT_PRINTF(X) \ 62 if (RSSADAPT_DO_PRINT()) \ 63 printf X 64 65 int ieee80211_rssadapt_debug = 0; 66 67 #else 68 #define RSSADAPT_DO_PRINT() (0) 69 #define RSSADAPT_PRINTF(X) 70 #endif 71 72 static struct ieee80211_rssadapt_expavgctl master_expavgctl = { 73 rc_decay_denom : 16, 74 rc_decay_old : 15, 75 rc_thresh_denom : 8, 76 rc_thresh_old : 4, 77 rc_avgrssi_denom : 8, 78 rc_avgrssi_old : 4 79 }; 80 81 #ifdef __NetBSD__ 82 #ifdef IEEE80211_DEBUG 83 /* TBD factor with sysctl_ath_verify, sysctl_ieee80211_verify. */ 84 static int 85 sysctl_ieee80211_rssadapt_debug(SYSCTLFN_ARGS) 86 { 87 int error, t; 88 struct sysctlnode node; 89 90 node = *rnode; 91 t = *(int*)rnode->sysctl_data; 92 node.sysctl_data = &t; 93 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 94 if (error || newp == NULL) 95 return (error); 96 97 IEEE80211_DPRINTF(("%s: t = %d, nodenum = %d, rnodenum = %d\n", 98 __func__, t, node.sysctl_num, rnode->sysctl_num)); 99 100 if (t < 0 || t > 2) 101 return (EINVAL); 102 *(int*)rnode->sysctl_data = t; 103 104 return (0); 105 } 106 #endif /* IEEE80211_DEBUG */ 107 108 /* TBD factor with sysctl_ath_verify, sysctl_ieee80211_verify. */ 109 static int 110 sysctl_ieee80211_rssadapt_expavgctl(SYSCTLFN_ARGS) 111 { 112 struct ieee80211_rssadapt_expavgctl rc; 113 int error; 114 struct sysctlnode node; 115 116 node = *rnode; 117 rc = *(struct ieee80211_rssadapt_expavgctl *)rnode->sysctl_data; 118 node.sysctl_data = &rc; 119 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 120 if (error || newp == NULL) 121 return (error); 122 123 IEEE80211_DPRINTF(("%s: decay = %d/%d, thresh = %d/%d, " 124 "avgrssi = %d/%d, nodenum = %d, rnodenum = %d\n", 125 __func__, rc.rc_decay_old, rc.rc_decay_denom, 126 rc.rc_thresh_old, rc.rc_thresh_denom, 127 rc.rc_avgrssi_old, rc.rc_avgrssi_denom, 128 node.sysctl_num, rnode->sysctl_num)); 129 130 if (rc.rc_decay_old < 0 || 131 rc.rc_decay_denom < rc.rc_decay_old) 132 return (EINVAL); 133 134 if (rc.rc_thresh_old < 0 || 135 rc.rc_thresh_denom < rc.rc_thresh_old) 136 return (EINVAL); 137 138 if (rc.rc_avgrssi_old < 0 || 139 rc.rc_avgrssi_denom < rc.rc_avgrssi_old) 140 return (EINVAL); 141 142 *(struct ieee80211_rssadapt_expavgctl *)rnode->sysctl_data = rc; 143 144 return (0); 145 } 146 147 /* 148 * Setup sysctl(3) MIB, net.ieee80211.* 149 * 150 * TBD condition CTLFLAG_PERMANENT on being an LKM or not 151 */ 152 SYSCTL_SETUP(sysctl_ieee80211_rssadapt, 153 "sysctl ieee80211 rssadapt subtree setup") 154 { 155 int rc; 156 struct sysctlnode *node; 157 158 if ((rc = sysctl_createv(clog, 0, NULL, &node, 159 CTLFLAG_PERMANENT, CTLTYPE_NODE, "net", NULL, 160 NULL, 0, NULL, 0, CTL_NET, CTL_EOL)) != 0) 161 goto err; 162 163 if ((rc = sysctl_createv(clog, 0, &node, &node, 164 CTLFLAG_PERMANENT, CTLTYPE_NODE, "link", NULL, 165 NULL, 0, NULL, 0, PF_LINK, CTL_EOL)) != 0) 166 goto err; 167 168 if ((rc = sysctl_createv(clog, 0, &node, &node, 169 CTLFLAG_PERMANENT, CTLTYPE_NODE, "ieee80211", NULL, 170 NULL, 0, NULL, 0, CTL_CREATE, CTL_EOL)) != 0) 171 goto err; 172 173 if ((rc = sysctl_createv(clog, 0, &node, &node, 174 CTLFLAG_PERMANENT, CTLTYPE_NODE, "rssadapt", 175 SYSCTL_DESCR("Received Signal Strength adaptation controls"), 176 NULL, 0, NULL, 0, CTL_CREATE, CTL_EOL)) != 0) 177 goto err; 178 179 #ifdef IEEE80211_DEBUG 180 /* control debugging printfs */ 181 if ((rc = sysctl_createv(clog, 0, &node, NULL, 182 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "debug", 183 SYSCTL_DESCR("Enable RSS adaptation debugging output"), 184 sysctl_ieee80211_rssadapt_debug, 0, &ieee80211_rssadapt_debug, 0, 185 CTL_CREATE, CTL_EOL)) != 0) 186 goto err; 187 #endif /* IEEE80211_DEBUG */ 188 189 /* control rate of decay for exponential averages */ 190 if ((rc = sysctl_createv(clog, 0, &node, NULL, 191 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_STRUCT, 192 "expavgctl", SYSCTL_DESCR("RSS exponential averaging control"), 193 sysctl_ieee80211_rssadapt_expavgctl, 0, 194 &master_expavgctl, sizeof(master_expavgctl), CTL_CREATE, 195 CTL_EOL)) != 0) 196 goto err; 197 198 return; 199 err: 200 printf("%s: sysctl_createv failed (rc = %d)\n", __func__, rc); 201 } 202 #endif /* __NetBSD__ */ 203 204 int 205 ieee80211_rssadapt_choose(struct ieee80211_rssadapt *ra, 206 struct ieee80211_rateset *rs, struct ieee80211_frame *wh, u_int len, 207 int fixed_rate, const char *dvname, int do_not_adapt) 208 { 209 u_int16_t (*thrs)[IEEE80211_RATE_SIZE]; 210 int flags = 0, i, rateidx = 0, thridx, top; 211 212 if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL) 213 flags |= IEEE80211_RATE_BASIC; 214 215 for (i = 0, top = IEEE80211_RSSADAPT_BKT0; 216 i < IEEE80211_RSSADAPT_BKTS; 217 i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) { 218 thridx = i; 219 if (len <= top) 220 break; 221 } 222 223 thrs = &ra->ra_rate_thresh[thridx]; 224 225 if (fixed_rate != -1) { 226 if ((rs->rs_rates[fixed_rate] & flags) == flags) { 227 rateidx = fixed_rate; 228 goto out; 229 } 230 flags |= IEEE80211_RATE_BASIC; 231 i = fixed_rate; 232 } else 233 i = rs->rs_nrates; 234 235 while (--i >= 0) { 236 rateidx = i; 237 if ((rs->rs_rates[i] & flags) != flags) 238 continue; 239 if (do_not_adapt) 240 break; 241 if ((*thrs)[i] < ra->ra_avg_rssi) 242 break; 243 } 244 245 out: 246 #ifdef IEEE80211_DEBUG 247 if (ieee80211_rssadapt_debug && dvname != NULL) { 248 printf("%s: dst %s threshold[%d, %d.%d] %d < %d\n", 249 dvname, ether_sprintf(wh->i_addr1), len, 250 (rs->rs_rates[rateidx] & IEEE80211_RATE_VAL) / 2, 251 (rs->rs_rates[rateidx] & IEEE80211_RATE_VAL) * 5 % 10, 252 (*thrs)[rateidx], ra->ra_avg_rssi); 253 } 254 #endif /* IEEE80211_DEBUG */ 255 return rateidx; 256 } 257 258 void 259 ieee80211_rssadapt_updatestats(struct ieee80211_rssadapt *ra) 260 { 261 long interval; 262 263 ra->ra_pktrate = 264 (ra->ra_pktrate + 10 * (ra->ra_nfail + ra->ra_nok)) / 2; 265 ra->ra_nfail = ra->ra_nok = 0; 266 267 /* a node is eligible for its rate to be raised every 1/10 to 10 268 * seconds, more eligible in proportion to recent packet rates. 269 */ 270 interval = MAX(100000, 10000000 / MAX(1, 10 * ra->ra_pktrate)); 271 ra->ra_raise_interval.tv_sec = interval / (1000 * 1000); 272 ra->ra_raise_interval.tv_usec = interval % (1000 * 1000); 273 } 274 275 void 276 ieee80211_rssadapt_input(struct ieee80211com *ic, struct ieee80211_node *ni, 277 struct ieee80211_rssadapt *ra, int rssi) 278 { 279 #ifdef IEEE80211_DEBUG 280 int last_avg_rssi = ra->ra_avg_rssi; 281 #endif 282 283 ra->ra_avg_rssi = interpolate(master_expavgctl.rc_avgrssi, 284 ra->ra_avg_rssi, (rssi << 8)); 285 286 RSSADAPT_PRINTF(("%s: src %s rssi %d avg %d -> %d\n", 287 ic->ic_if.if_xname, ether_sprintf(ni->ni_macaddr), 288 rssi, last_avg_rssi, ra->ra_avg_rssi)); 289 } 290 291 /* 292 * Adapt the data rate to suit the conditions. When a transmitted 293 * packet is dropped after IEEE80211_RSSADAPT_RETRY_LIMIT retransmissions, 294 * raise the RSS threshold for transmitting packets of similar length at 295 * the same data rate. 296 */ 297 void 298 ieee80211_rssadapt_lower_rate(struct ieee80211com *ic, 299 struct ieee80211_node *ni, struct ieee80211_rssadapt *ra, 300 struct ieee80211_rssdesc *id) 301 { 302 struct ieee80211_rateset *rs = &ni->ni_rates; 303 u_int16_t last_thr; 304 u_int i, thridx, top; 305 306 ra->ra_nfail++; 307 308 if (id->id_rateidx >= rs->rs_nrates) { 309 RSSADAPT_PRINTF(("ieee80211_rssadapt_lower_rate: " 310 "%s rate #%d > #%d out of bounds\n", 311 ether_sprintf(ni->ni_macaddr), id->id_rateidx, 312 rs->rs_nrates - 1)); 313 return; 314 } 315 316 for (i = 0, top = IEEE80211_RSSADAPT_BKT0; 317 i < IEEE80211_RSSADAPT_BKTS; 318 i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) { 319 thridx = i; 320 if (id->id_len <= top) 321 break; 322 } 323 324 last_thr = ra->ra_rate_thresh[thridx][id->id_rateidx]; 325 ra->ra_rate_thresh[thridx][id->id_rateidx] = 326 interpolate(master_expavgctl.rc_thresh, last_thr, 327 (id->id_rssi << 8)); 328 329 RSSADAPT_PRINTF(("%s: dst %s rssi %d threshold[%d, %d.%d] %d -> %d\n", 330 ic->ic_if.if_xname, ether_sprintf(ni->ni_macaddr), 331 id->id_rssi, id->id_len, 332 (rs->rs_rates[id->id_rateidx] & IEEE80211_RATE_VAL) / 2, 333 (rs->rs_rates[id->id_rateidx] & IEEE80211_RATE_VAL) * 5 % 10, 334 last_thr, ra->ra_rate_thresh[thridx][id->id_rateidx])); 335 } 336 337 void 338 ieee80211_rssadapt_raise_rate(struct ieee80211com *ic, 339 struct ieee80211_rssadapt *ra, struct ieee80211_rssdesc *id) 340 { 341 u_int16_t (*thrs)[IEEE80211_RATE_SIZE], newthr, oldthr; 342 struct ieee80211_node *ni = id->id_node; 343 struct ieee80211_rateset *rs = &ni->ni_rates; 344 int i, rate, top; 345 #ifdef IEEE80211_DEBUG 346 int j; 347 #endif 348 349 ra->ra_nok++; 350 351 if (!ratecheck(&ra->ra_last_raise, &ra->ra_raise_interval)) 352 return; 353 354 for (i = 0, top = IEEE80211_RSSADAPT_BKT0; 355 i < IEEE80211_RSSADAPT_BKTS; 356 i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) { 357 thrs = &ra->ra_rate_thresh[i]; 358 if (id->id_len <= top) 359 break; 360 } 361 362 if (id->id_rateidx + 1 < rs->rs_nrates && 363 (*thrs)[id->id_rateidx + 1] > (*thrs)[id->id_rateidx]) { 364 rate = (rs->rs_rates[id->id_rateidx + 1] & IEEE80211_RATE_VAL); 365 366 RSSADAPT_PRINTF(("%s: threshold[%d, %d.%d] decay %d ", 367 ic->ic_if.if_xname, 368 IEEE80211_RSSADAPT_BKT0 << (IEEE80211_RSSADAPT_BKTPOWER* i), 369 rate / 2, rate * 5 % 10, (*thrs)[id->id_rateidx + 1])); 370 oldthr = (*thrs)[id->id_rateidx + 1]; 371 if ((*thrs)[id->id_rateidx] == 0) 372 newthr = ra->ra_avg_rssi; 373 else 374 newthr = (*thrs)[id->id_rateidx]; 375 (*thrs)[id->id_rateidx + 1] = 376 interpolate(master_expavgctl.rc_decay, oldthr, newthr); 377 378 RSSADAPT_PRINTF(("-> %d\n", (*thrs)[id->id_rateidx + 1])); 379 } 380 381 #ifdef IEEE80211_DEBUG 382 if (RSSADAPT_DO_PRINT()) { 383 printf("%s: dst %s thresholds\n", ic->ic_if.if_xname, 384 ether_sprintf(ni->ni_macaddr)); 385 for (i = 0; i < IEEE80211_RSSADAPT_BKTS; i++) { 386 printf("%d-byte", IEEE80211_RSSADAPT_BKT0 << (IEEE80211_RSSADAPT_BKTPOWER * i)); 387 for (j = 0; j < rs->rs_nrates; j++) { 388 rate = (rs->rs_rates[j] & IEEE80211_RATE_VAL); 389 printf(", T[%d.%d] = %d", rate / 2, 390 rate * 5 % 10, ra->ra_rate_thresh[i][j]); 391 } 392 printf("\n"); 393 } 394 } 395 #endif /* IEEE80211_DEBUG */ 396 } 397
Indexes created Mon Sep 22 05:09:51 GMT 2025