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 /*      $FreeBSD: head/sys/net80211/ieee80211_rssadapt.c 343417 2019-01-25 01:05:18Z avos $     */
    2 /* $NetBSD: ieee80211_rssadapt.c,v 1.9 2005/02/26 22:45:09 perry Exp $ */
    3 /*-
    4  * SPDX-License-Identifier: BSD-3-Clause
    5  *
    6  * Copyright (c) 2010 Rui Paulo <rpaulo@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 #include <sys/socket.h>
   43 #include <sys/sysctl.h>
   44 
   45 #include <net/if.h>
   46 #include <net/if_var.h>
   47 #include <net/if_media.h>
   48 #include <net/ethernet.h>
   49 
   50 #include <net80211/ieee80211_var.h>
   51 #include <net80211/ieee80211_rssadapt.h>
   52 #include <net80211/ieee80211_ratectl.h>
   53 
   54 struct rssadapt_expavgctl {
   55         /* RSS threshold decay. */
   56         u_int rc_decay_denom;
   57         u_int rc_decay_old;
   58         /* RSS threshold update. */
   59         u_int rc_thresh_denom;
   60         u_int rc_thresh_old;
   61         /* RSS average update. */
   62         u_int rc_avgrssi_denom;
   63         u_int rc_avgrssi_old;
   64 };
   65 
   66 static struct rssadapt_expavgctl master_expavgctl = {
   67         .rc_decay_denom = 16,
   68         .rc_decay_old = 15,
   69         .rc_thresh_denom = 8,
   70         .rc_thresh_old = 4,
   71         .rc_avgrssi_denom = 8,
   72         .rc_avgrssi_old = 4
   73 };
   74 
   75 #ifdef interpolate
   76 #undef interpolate
   77 #endif
   78 #define interpolate(parm, old, new) ((parm##_old * (old) + \
   79                                      (parm##_denom - parm##_old) * (new)) / \
   80                                     parm##_denom)
   81 
   82 static void     rssadapt_setinterval(const struct ieee80211vap *, int);
   83 static void     rssadapt_init(struct ieee80211vap *);
   84 static void     rssadapt_deinit(struct ieee80211vap *);
   85 static void     rssadapt_updatestats(struct ieee80211_rssadapt_node *);
   86 static void     rssadapt_node_init(struct ieee80211_node *);
   87 static void     rssadapt_node_deinit(struct ieee80211_node *);
   88 static int      rssadapt_rate(struct ieee80211_node *, void *, uint32_t);
   89 static void     rssadapt_lower_rate(struct ieee80211_rssadapt_node *, int, int);
   90 static void     rssadapt_raise_rate(struct ieee80211_rssadapt_node *,
   91                         int, int);
   92 static void     rssadapt_tx_complete(const struct ieee80211_node *,
   93                         const struct ieee80211_ratectl_tx_status *);
   94 static void     rssadapt_sysctlattach(struct ieee80211vap *,
   95                         struct sysctl_ctx_list *, struct sysctl_oid *);
   96 
   97 /* number of references from net80211 layer */
   98 static  int nrefs = 0;
   99 
  100 static const struct ieee80211_ratectl rssadapt = {
  101         .ir_name        = "rssadapt",
  102         .ir_attach      = NULL,
  103         .ir_detach      = NULL,
  104         .ir_init        = rssadapt_init,
  105         .ir_deinit      = rssadapt_deinit,
  106         .ir_node_init   = rssadapt_node_init,
  107         .ir_node_deinit = rssadapt_node_deinit,
  108         .ir_rate        = rssadapt_rate,
  109         .ir_tx_complete = rssadapt_tx_complete,
  110         .ir_tx_update   = NULL,
  111         .ir_setinterval = rssadapt_setinterval,
  112 };
  113 IEEE80211_RATECTL_MODULE(rssadapt, 1);
  114 IEEE80211_RATECTL_ALG(rssadapt, IEEE80211_RATECTL_RSSADAPT, rssadapt);
  115 
  116 static void
  117 rssadapt_setinterval(const struct ieee80211vap *vap, int msecs)
  118 {
  119         struct ieee80211_rssadapt *rs = vap->iv_rs;
  120 
  121         if (!rs)
  122                 return;
  123 
  124         if (msecs < 100)
  125                 msecs = 100;
  126         rs->interval = msecs_to_ticks(msecs);
  127 }
  128 
  129 static void
  130 rssadapt_init(struct ieee80211vap *vap)
  131 {
  132         struct ieee80211_rssadapt *rs;
  133 
  134         KASSERT(vap->iv_rs == NULL, ("%s: iv_rs already initialized",
  135             __func__));
  136 
  137         nrefs++;                /* XXX locking */
  138         vap->iv_rs = rs = IEEE80211_MALLOC(sizeof(struct ieee80211_rssadapt),
  139             M_80211_RATECTL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO);
  140         if (rs == NULL) {
  141                 if_printf(vap->iv_ifp, "couldn't alloc ratectl structure\n");
  142                 return;
  143         }
  144         rs->vap = vap;
  145         rssadapt_setinterval(vap, 500 /* msecs */);
  146         rssadapt_sysctlattach(vap, vap->iv_sysctl, vap->iv_oid);
  147 }
  148 
  149 static void
  150 rssadapt_deinit(struct ieee80211vap *vap)
  151 {
  152         IEEE80211_FREE(vap->iv_rs, M_80211_RATECTL);
  153         KASSERT(nrefs > 0, ("imbalanced attach/detach"));
  154         nrefs--;                /* XXX locking */
  155 }
  156 
  157 static void
  158 rssadapt_updatestats(struct ieee80211_rssadapt_node *ra)
  159 {
  160         long interval;
  161 
  162         ra->ra_pktrate = (ra->ra_pktrate + 10*(ra->ra_nfail + ra->ra_nok))/2;
  163         ra->ra_nfail = ra->ra_nok = 0;
  164 
  165         /*
  166          * A node is eligible for its rate to be raised every 1/10 to 10
  167          * seconds, more eligible in proportion to recent packet rates.
  168          */
  169         interval = MAX(10*1000, 10*1000 / MAX(1, 10 * ra->ra_pktrate));
  170         ra->ra_raise_interval = msecs_to_ticks(interval);
  171 }
  172 
  173 static void
  174 rssadapt_node_init(struct ieee80211_node *ni)
  175 {
  176         struct ieee80211_rssadapt_node *ra;
  177         struct ieee80211vap *vap = ni->ni_vap;
  178         struct ieee80211_rssadapt *rsa = vap->iv_rs;
  179         const struct ieee80211_rateset *rs = &ni->ni_rates;
  180 
  181         if (!rsa) {
  182                 if_printf(vap->iv_ifp, "ratectl structure was not allocated, "
  183                     "per-node structure allocation skipped\n");
  184                 return;
  185         }
  186 
  187         if (ni->ni_rctls == NULL) {
  188                 ni->ni_rctls = ra = 
  189                     IEEE80211_MALLOC(sizeof(struct ieee80211_rssadapt_node),
  190                         M_80211_RATECTL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO);
  191                 if (ra == NULL) {
  192                         if_printf(vap->iv_ifp, "couldn't alloc per-node ratectl "
  193                             "structure\n");
  194                         return;
  195                 }
  196         } else
  197                 ra = ni->ni_rctls;
  198         ra->ra_rs = rsa;
  199         ra->ra_rates = *rs;
  200         rssadapt_updatestats(ra);
  201 
  202         /* pick initial rate */
  203         for (ra->ra_rix = rs->rs_nrates - 1;
  204              ra->ra_rix > 0 && (rs->rs_rates[ra->ra_rix] & IEEE80211_RATE_VAL) > 72;
  205              ra->ra_rix--)
  206                 ;
  207         ni->ni_txrate = rs->rs_rates[ra->ra_rix] & IEEE80211_RATE_VAL;
  208         ra->ra_ticks = ticks;
  209 
  210         IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
  211             "RSSADAPT initial rate %d", ni->ni_txrate);
  212 }
  213 
  214 static void
  215 rssadapt_node_deinit(struct ieee80211_node *ni)
  216 {
  217 
  218         IEEE80211_FREE(ni->ni_rctls, M_80211_RATECTL);
  219 }
  220 
  221 static __inline int
  222 bucket(int pktlen)
  223 {
  224         int i, top, thridx;
  225 
  226         for (i = 0, top = IEEE80211_RSSADAPT_BKT0;
  227              i < IEEE80211_RSSADAPT_BKTS;
  228              i++, top <<= IEEE80211_RSSADAPT_BKTPOWER) {
  229                 thridx = i;
  230                 if (pktlen <= top)
  231                         break;
  232         }
  233         return thridx;
  234 }
  235 
  236 static int
  237 rssadapt_rate(struct ieee80211_node *ni, void *arg __unused, uint32_t iarg)
  238 {
  239         struct ieee80211_rssadapt_node *ra = ni->ni_rctls;
  240         u_int pktlen = iarg;
  241         const struct ieee80211_rateset *rs;
  242         uint16_t (*thrs)[IEEE80211_RATE_SIZE];
  243         int rix, rssi;
  244 
  245         /* XXX should return -1 here, but drivers may not expect this... */
  246         if (!ra)
  247         {
  248                 ni->ni_txrate = ni->ni_rates.rs_rates[0];
  249                 return 0;
  250         }
  251 
  252         rs = &ra->ra_rates;
  253         if ((ticks - ra->ra_ticks) > ra->ra_rs->interval) {
  254                 rssadapt_updatestats(ra);
  255                 ra->ra_ticks = ticks;
  256         }
  257 
  258         thrs = &ra->ra_rate_thresh[bucket(pktlen)];
  259 
  260         /* XXX this is average rssi, should be using last value */
  261         rssi = ni->ni_ic->ic_node_getrssi(ni);
  262         for (rix = rs->rs_nrates-1; rix >= 0; rix--)
  263                 if ((*thrs)[rix] < (rssi << 8))
  264                         break;
  265         if (rix != ra->ra_rix) {
  266                 /* update public rate */
  267                 ni->ni_txrate = ni->ni_rates.rs_rates[rix] & IEEE80211_RATE_VAL;
  268                 ra->ra_rix = rix;
  269 
  270                 IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
  271                     "RSSADAPT new rate %d (pktlen %d rssi %d)",
  272                     ni->ni_txrate, pktlen, rssi);
  273         }
  274         return rix;
  275 }
  276 
  277 /*
  278  * Adapt the data rate to suit the conditions.  When a transmitted
  279  * packet is dropped after RAL_RSSADAPT_RETRY_LIMIT retransmissions,
  280  * raise the RSS threshold for transmitting packets of similar length at
  281  * the same data rate.
  282  */
  283 static void
  284 rssadapt_lower_rate(struct ieee80211_rssadapt_node *ra, int pktlen, int rssi)
  285 {
  286         uint16_t last_thr;
  287         uint16_t (*thrs)[IEEE80211_RATE_SIZE];
  288         u_int rix;
  289 
  290         thrs = &ra->ra_rate_thresh[bucket(pktlen)];
  291 
  292         rix = ra->ra_rix;
  293         last_thr = (*thrs)[rix];
  294         (*thrs)[rix] = interpolate(master_expavgctl.rc_thresh,
  295             last_thr, (rssi << 8));
  296 
  297         IEEE80211_DPRINTF(ra->ra_rs->vap, IEEE80211_MSG_RATECTL,
  298             "RSSADAPT lower threshold for rate %d (last_thr %d new thr %d rssi %d)\n",
  299             ra->ra_rates.rs_rates[rix + 1] & IEEE80211_RATE_VAL,
  300             last_thr, (*thrs)[rix], rssi);
  301 }
  302 
  303 static void
  304 rssadapt_raise_rate(struct ieee80211_rssadapt_node *ra, int pktlen, int rssi)
  305 {
  306         uint16_t (*thrs)[IEEE80211_RATE_SIZE];
  307         uint16_t newthr, oldthr;
  308         int rix;
  309 
  310         thrs = &ra->ra_rate_thresh[bucket(pktlen)];
  311 
  312         rix = ra->ra_rix;
  313         if ((*thrs)[rix + 1] > (*thrs)[rix]) {
  314                 oldthr = (*thrs)[rix + 1];
  315                 if ((*thrs)[rix] == 0)
  316                         newthr = (rssi << 8);
  317                 else
  318                         newthr = (*thrs)[rix];
  319                 (*thrs)[rix + 1] = interpolate(master_expavgctl.rc_decay,
  320                     oldthr, newthr);
  321 
  322                 IEEE80211_DPRINTF(ra->ra_rs->vap, IEEE80211_MSG_RATECTL,
  323                     "RSSADAPT raise threshold for rate %d (oldthr %d newthr %d rssi %d)\n",
  324                     ra->ra_rates.rs_rates[rix + 1] & IEEE80211_RATE_VAL,
  325                     oldthr, newthr, rssi);
  326 
  327                 ra->ra_last_raise = ticks;
  328         }
  329 }
  330 
  331 static void
  332 rssadapt_tx_complete(const struct ieee80211_node *ni,
  333     const struct ieee80211_ratectl_tx_status *status)
  334 {
  335         struct ieee80211_rssadapt_node *ra = ni->ni_rctls;
  336         int pktlen, rssi;
  337 
  338         if (!ra)
  339                 return;
  340 
  341         if ((status->flags &
  342             (IEEE80211_RATECTL_STATUS_PKTLEN|IEEE80211_RATECTL_STATUS_RSSI)) !=
  343             (IEEE80211_RATECTL_STATUS_PKTLEN|IEEE80211_RATECTL_STATUS_RSSI))
  344                 return;
  345 
  346         pktlen = status->pktlen;
  347         rssi = status->rssi;
  348 
  349         if (status->status == IEEE80211_RATECTL_TX_SUCCESS) {
  350                 ra->ra_nok++;
  351                 if ((ra->ra_rix + 1) < ra->ra_rates.rs_nrates &&
  352                     (ticks - ra->ra_last_raise) >= ra->ra_raise_interval)
  353                         rssadapt_raise_rate(ra, pktlen, rssi);
  354         } else {
  355                 ra->ra_nfail++;
  356                 rssadapt_lower_rate(ra, pktlen, rssi);
  357         }
  358 }
  359 
  360 static int
  361 rssadapt_sysctl_interval(SYSCTL_HANDLER_ARGS)
  362 {
  363         struct ieee80211vap *vap = arg1;
  364         struct ieee80211_rssadapt *rs = vap->iv_rs;
  365         int msecs, error;
  366 
  367         if (!rs)
  368                 return ENOMEM;
  369 
  370         msecs = ticks_to_msecs(rs->interval);
  371         error = sysctl_handle_int(oidp, &msecs, 0, req);
  372         if (error || !req->newptr)
  373                 return error;
  374         rssadapt_setinterval(vap, msecs);
  375         return 0;
  376 }
  377 
  378 static void
  379 rssadapt_sysctlattach(struct ieee80211vap *vap,
  380     struct sysctl_ctx_list *ctx, struct sysctl_oid *tree)
  381 {
  382 
  383         SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
  384             "rssadapt_rate_interval", CTLTYPE_INT | CTLFLAG_RW, vap,
  385             0, rssadapt_sysctl_interval, "I", "rssadapt operation interval (ms)");
  386 }

Cache object: 37e88bcc95b8d7546f267dfe737d4f9c


[ 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.