The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/net80211/ieee80211_rssadapt.c

Version: -  FREEBSD  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-2  -  FREEBSD-11-1  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-4  -  FREEBSD-10-3  -  FREEBSD-10-2  -  FREEBSD-10-1  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-3  -  FREEBSD-9-2  -  FREEBSD-9-1  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-4  -  FREEBSD-8-3  -  FREEBSD-8-2  -  FREEBSD-8-1  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-4  -  FREEBSD-7-3  -  FREEBSD-7-2  -  FREEBSD-7-1  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-4  -  FREEBSD-6-3  -  FREEBSD-6-2  -  FREEBSD-6-1  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-5  -  FREEBSD-5-4  -  FREEBSD-5-3  -  FREEBSD-5-2  -  FREEBSD-5-1  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1 
SearchContext: -  none  -  3  -  10 

    1 /* $NetBSD: ieee80211_rssadapt.c,v 1.3 2004/03/17 17:00:34 dyoung 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 
   36 #include <net/if.h>
   37 #include <net/if_media.h>
   38 #include <net/if_ether.h>
   39 
   40 #include <net80211/ieee80211_var.h>
   41 #include <net80211/ieee80211.h>
   42 #include <net80211/ieee80211_compat.h>
   43 #include <net80211/ieee80211_rssadapt.h>
   44 
   45 #ifdef interpolate
   46 #undef interpolate
   47 #endif
   48 #define interpolate(parm, old, new) ((parm##_old * (old) + \
   49                                      (parm##_denom - parm##_old) * (new)) / \
   50                                     parm##_denom)
   51 
   52 #ifdef IEEE80211_DEBUG
   53 static  struct timeval lastrateadapt;   /* time of last rate adaptation msg */
   54 static  int currssadaptps = 0;          /* rate-adaptation msgs this second */
   55 static  int ieee80211_adaptrate = 4;    /* rate-adaptation max msgs/sec */
   56 
   57 #define RSSADAPT_DO_PRINT() \
   58         ((ieee80211_debug > 0) && \
   59          ppsratecheck(&lastrateadapt, &currssadaptps, ieee80211_adaptrate))
   60 #define RSSADAPT_PRINTF(X) \
   61         if (RSSADAPT_DO_PRINT()) \
   62                 printf X
   63 
   64 #else
   65 #define RSSADAPT_DO_PRINT() (0)
   66 #define RSSADAPT_PRINTF(X)
   67 #endif
   68 
   69 struct ieee80211_rssadapt_expavgctl master_expavgctl = {
   70         rc_decay_denom : 16,
   71         rc_decay_old : 15,
   72         rc_thresh_denom : 8,
   73         rc_thresh_old : 4,
   74         rc_avgrssi_denom : 8,
   75         rc_avgrssi_old : 4
   76 };
   77 
   78 int
   79 ieee80211_rssadapt_choose(struct ieee80211_rssadapt *ra,
   80     struct ieee80211_rateset *rs, struct ieee80211_frame *wh, u_int len,
   81     int fixed_rate, const char *dvname, int do_not_adapt)
   82 {
   83         u_int16_t (*thrs)[IEEE80211_RATE_SIZE];
   84         int flags = 0, i, rateidx = 0, thridx, top;
   85 
   86         if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL)
   87                 flags |= IEEE80211_RATE_BASIC;
   88 
   89         for (i = 0, top = IEEE80211_RSSADAPT_BKT0;
   90              i < IEEE80211_RSSADAPT_BKTS;
   91              i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) {
   92                 thridx = i;
   93                 if (len <= top)
   94                         break;
   95         }
   96 
   97         thrs = &ra->ra_rate_thresh[thridx];
   98 
   99         if (fixed_rate != -1) {
  100                 if ((rs->rs_rates[fixed_rate] & flags) == flags) {
  101                         rateidx = fixed_rate;
  102                         goto out;
  103                 }
  104                 flags |= IEEE80211_RATE_BASIC;
  105                 i = fixed_rate;
  106         } else
  107                 i = rs->rs_nrates;
  108 
  109         while (--i >= 0) {
  110                 rateidx = i;
  111                 if ((rs->rs_rates[i] & flags) != flags)
  112                         continue;
  113                 if (do_not_adapt)
  114                         break;
  115                 if ((*thrs)[i] < ra->ra_avg_rssi)
  116                         break;
  117         }
  118 
  119 out:
  120         if (dvname != NULL) {
  121                 printf("%s: dst %s threshold[%d, %d.%d] %d < %d\n",
  122                     dvname, ether_sprintf(wh->i_addr1), len,
  123                     (rs->rs_rates[rateidx] & IEEE80211_RATE_VAL) / 2,
  124                     (rs->rs_rates[rateidx] & IEEE80211_RATE_VAL) * 5 % 10,
  125                     (*thrs)[rateidx], ra->ra_avg_rssi);
  126         }
  127         return rateidx;
  128 }
  129 
  130 void
  131 ieee80211_rssadapt_updatestats(struct ieee80211_rssadapt *ra)
  132 {
  133         long interval; 
  134 
  135         ra->ra_pktrate =
  136             (ra->ra_pktrate + 10 * (ra->ra_nfail + ra->ra_nok)) / 2;
  137         ra->ra_nfail = ra->ra_nok = 0;
  138 
  139         /* a node is eligible for its rate to be raised every 1/10 to 10
  140          * seconds, more eligible in proportion to recent packet rates.
  141          */
  142         interval = MAX(100000, 10000000 / MAX(1, 10 * ra->ra_pktrate));
  143         ra->ra_raise_interval.tv_sec = interval / (1000 * 1000);
  144         ra->ra_raise_interval.tv_usec = interval % (1000 * 1000);
  145 }
  146 
  147 void
  148 ieee80211_rssadapt_input(struct ieee80211com *ic, struct ieee80211_node *ni,
  149     struct ieee80211_rssadapt *ra, int rssi)
  150 {
  151 #ifdef IEEE80211_DEBUG
  152         int last_avg_rssi = ra->ra_avg_rssi;
  153 #endif
  154 
  155         ra->ra_avg_rssi = interpolate(master_expavgctl.rc_avgrssi,
  156                                       ra->ra_avg_rssi, (rssi << 8));
  157 
  158         RSSADAPT_PRINTF(("%s: src %s rssi %d avg %d -> %d\n",
  159             ic->ic_if.if_xname, ether_sprintf(ni->ni_macaddr),
  160             rssi, last_avg_rssi, ra->ra_avg_rssi));
  161 }
  162 
  163 /*
  164  * Adapt the data rate to suit the conditions.  When a transmitted
  165  * packet is dropped after IEEE80211_RSSADAPT_RETRY_LIMIT retransmissions,
  166  * raise the RSS threshold for transmitting packets of similar length at
  167  * the same data rate.
  168  */
  169 void
  170 ieee80211_rssadapt_lower_rate(struct ieee80211com *ic,
  171     struct ieee80211_node *ni, struct ieee80211_rssadapt *ra,
  172     struct ieee80211_rssdesc *id)
  173 {
  174         struct ieee80211_rateset *rs = &ni->ni_rates;
  175         u_int16_t last_thr;
  176         u_int i, thridx, top;
  177 
  178         ra->ra_nok++;
  179 
  180         if (id->id_rateidx >= rs->rs_nrates) {
  181                 RSSADAPT_PRINTF(("ieee80211_rssadapt_lower_rate: "
  182                     "%s rate #%d > #%d out of bounds\n",
  183                     ether_sprintf(ni->ni_macaddr), id->id_rateidx,
  184                         rs->rs_nrates - 1));
  185                 return;
  186         }
  187 
  188         for (i = 0, top = IEEE80211_RSSADAPT_BKT0;
  189              i < IEEE80211_RSSADAPT_BKTS;
  190              i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) {
  191                 thridx = i;
  192                 if (id->id_len <= top)
  193                         break;
  194         }
  195 
  196         last_thr = ra->ra_rate_thresh[thridx][id->id_rateidx];
  197         ra->ra_rate_thresh[thridx][id->id_rateidx] =
  198             interpolate(master_expavgctl.rc_thresh, last_thr,
  199                         (id->id_rssi << 8));
  200 
  201         RSSADAPT_PRINTF(("%s: dst %s rssi %d threshold[%d, %d.%d] %d -> %d\n",
  202             ic->ic_if.if_xname, ether_sprintf(ni->ni_macaddr),
  203             id->id_rssi, id->id_len,
  204             (rs->rs_rates[id->id_rateidx] & IEEE80211_RATE_VAL) / 2,
  205             (rs->rs_rates[id->id_rateidx] & IEEE80211_RATE_VAL) * 5 % 10,
  206             last_thr, ra->ra_rate_thresh[thridx][id->id_rateidx]));
  207 }
  208 
  209 void
  210 ieee80211_rssadapt_raise_rate(struct ieee80211com *ic,
  211     struct ieee80211_rssadapt *ra, struct ieee80211_rssdesc *id)
  212 {
  213         u_int16_t (*thrs)[IEEE80211_RATE_SIZE], newthr, oldthr;
  214         struct ieee80211_node *ni = id->id_node;
  215         struct ieee80211_rateset *rs = &ni->ni_rates;
  216         int i, rate, top;
  217 #ifdef IEEE80211_DEBUG
  218         int j;
  219 #endif
  220 
  221         ra->ra_nfail++;
  222 
  223         if (!ratecheck(&ra->ra_last_raise, &ra->ra_raise_interval))
  224                 return;
  225 
  226         for (i = 0, top = IEEE80211_RSSADAPT_BKT0;
  227              i < IEEE80211_RSSADAPT_BKTS;
  228              i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) {
  229                 thrs = &ra->ra_rate_thresh[i];
  230                 if (id->id_len <= top)
  231                         break;
  232         }
  233 
  234         if (id->id_rateidx + 1 < rs->rs_nrates &&
  235             (*thrs)[id->id_rateidx + 1] > (*thrs)[id->id_rateidx]) {
  236                 rate = (rs->rs_rates[id->id_rateidx + 1] & IEEE80211_RATE_VAL);
  237 
  238                 RSSADAPT_PRINTF(("%s: threshold[%d, %d.%d] decay %d ",
  239                     ic->ic_if.if_xname,
  240                     IEEE80211_RSSADAPT_BKT0 << (IEEE80211_RSSADAPT_BKTPOWER* i),
  241                     rate / 2, rate * 5 % 10, (*thrs)[id->id_rateidx + 1]));
  242                 oldthr = (*thrs)[id->id_rateidx + 1];
  243                 if ((*thrs)[id->id_rateidx] == 0)
  244                         newthr = ra->ra_avg_rssi;
  245                 else
  246                         newthr = (*thrs)[id->id_rateidx];
  247                 (*thrs)[id->id_rateidx + 1] =
  248                     interpolate(master_expavgctl.rc_decay, oldthr, newthr);
  249 
  250                 RSSADAPT_PRINTF(("-> %d\n", (*thrs)[id->id_rateidx + 1]));
  251         }
  252 
  253 #ifdef IEEE80211_DEBUG
  254         if (RSSADAPT_DO_PRINT()) {
  255                 printf("%s: dst %s thresholds\n", ic->ic_if.if_xname,
  256                     ether_sprintf(ni->ni_macaddr));
  257                 for (i = 0; i < IEEE80211_RSSADAPT_BKTS; i++) {
  258                         printf("%d-byte", IEEE80211_RSSADAPT_BKT0 << (IEEE80211_RSSADAPT_BKTPOWER * i));
  259                         for (j = 0; j < rs->rs_nrates; j++) {
  260                                 rate = (rs->rs_rates[j] & IEEE80211_RATE_VAL);
  261                                 printf(", T[%d.%d] = %d", rate / 2,
  262                                     rate * 5 % 10, ra->ra_rate_thresh[i][j]);
  263                         }
  264                         printf("\n");
  265                 }
  266         }
  267 #endif /* IEEE80211_DEBUG */
  268 }

Cache object: d18d9930992e314c6dc21b2dc3f01879


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.