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_amrr.c

Version: -  FREEBSD  -  FREEBSD11  -  FREEBSD10  -  FREEBSD9  -  FREEBSD92  -  FREEBSD91  -  FREEBSD90  -  FREEBSD8  -  FREEBSD82  -  FREEBSD81  -  FREEBSD80  -  FREEBSD7  -  FREEBSD74  -  FREEBSD73  -  FREEBSD72  -  FREEBSD71  -  FREEBSD70  -  FREEBSD6  -  FREEBSD64  -  FREEBSD63  -  FREEBSD62  -  FREEBSD61  -  FREEBSD60  -  FREEBSD5  -  FREEBSD55  -  FREEBSD54  -  FREEBSD53  -  FREEBSD52  -  FREEBSD51  -  FREEBSD50  -  FREEBSD4  -  FREEBSD3  -  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 /*      $OpenBSD: ieee80211_amrr.c,v 1.1 2006/06/17 19:07:19 damien Exp $       */
    2 
    3 /*-
    4  * Copyright (c) 2010 Rui Paulo <rpaulo@FreeBSD.org>
    5  * Copyright (c) 2006
    6  *      Damien Bergamini <damien.bergamini@free.fr>
    7  *
    8  * Permission to use, copy, modify, and distribute this software for any
    9  * purpose with or without fee is hereby granted, provided that the above
   10  * copyright notice and this permission notice appear in all copies.
   11  *
   12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   16  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   17  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   18  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   19  */
   20 
   21 #include <sys/cdefs.h>
   22 __FBSDID("$FreeBSD: stable/8/sys/net80211/ieee80211_amrr.c 238027 2012-07-02 20:36:54Z mdf $");
   23 
   24 /*-
   25  * Naive implementation of the Adaptive Multi Rate Retry algorithm:
   26  *
   27  * "IEEE 802.11 Rate Adaptation: A Practical Approach"
   28  *  Mathieu Lacage, Hossein Manshaei, Thierry Turletti
   29  *  INRIA Sophia - Projet Planete
   30  *  http://www-sop.inria.fr/rapports/sophia/RR-5208.html
   31  */
   32 #include "opt_wlan.h"
   33 
   34 #include <sys/param.h>
   35 #include <sys/kernel.h>
   36 #include <sys/module.h>
   37 #include <sys/socket.h>
   38 #include <sys/sysctl.h>
   39 
   40 #include <net/if.h>
   41 #include <net/if_media.h>
   42 
   43 #ifdef INET
   44 #include <netinet/in.h>
   45 #include <netinet/if_ether.h>
   46 #endif
   47 
   48 #include <net80211/ieee80211_var.h>
   49 #include <net80211/ieee80211_amrr.h>
   50 #include <net80211/ieee80211_ratectl.h>
   51 
   52 #define is_success(amn) \
   53         ((amn)->amn_retrycnt < (amn)->amn_txcnt / 10)
   54 #define is_failure(amn) \
   55         ((amn)->amn_retrycnt > (amn)->amn_txcnt / 3)
   56 #define is_enough(amn)          \
   57         ((amn)->amn_txcnt > 10)
   58 
   59 static void     amrr_setinterval(const struct ieee80211vap *, int);
   60 static void     amrr_init(struct ieee80211vap *);
   61 static void     amrr_deinit(struct ieee80211vap *);
   62 static void     amrr_node_init(struct ieee80211_node *);
   63 static void     amrr_node_deinit(struct ieee80211_node *);
   64 static int      amrr_update(struct ieee80211_amrr *,
   65                         struct ieee80211_amrr_node *, struct ieee80211_node *);
   66 static int      amrr_rate(struct ieee80211_node *, void *, uint32_t);
   67 static void     amrr_tx_complete(const struct ieee80211vap *,
   68                         const struct ieee80211_node *, int, 
   69                         void *, void *);
   70 static void     amrr_tx_update(const struct ieee80211vap *vap,
   71                         const struct ieee80211_node *, void *, void *, void *);
   72 static void     amrr_sysctlattach(struct ieee80211vap *,
   73                         struct sysctl_ctx_list *, struct sysctl_oid *);
   74 
   75 /* number of references from net80211 layer */
   76 static  int nrefs = 0;
   77 
   78 static const struct ieee80211_ratectl amrr = {
   79         .ir_name        = "amrr",
   80         .ir_attach      = NULL,
   81         .ir_detach      = NULL,
   82         .ir_init        = amrr_init,
   83         .ir_deinit      = amrr_deinit,
   84         .ir_node_init   = amrr_node_init,
   85         .ir_node_deinit = amrr_node_deinit,
   86         .ir_rate        = amrr_rate,
   87         .ir_tx_complete = amrr_tx_complete,
   88         .ir_tx_update   = amrr_tx_update,
   89         .ir_setinterval = amrr_setinterval,
   90 };
   91 IEEE80211_RATECTL_MODULE(amrr, 1);
   92 IEEE80211_RATECTL_ALG(amrr, IEEE80211_RATECTL_AMRR, amrr);
   93 
   94 static void
   95 amrr_setinterval(const struct ieee80211vap *vap, int msecs)
   96 {
   97         struct ieee80211_amrr *amrr = vap->iv_rs;
   98         int t;
   99 
  100         if (msecs < 100)
  101                 msecs = 100;
  102         t = msecs_to_ticks(msecs);
  103         amrr->amrr_interval = (t < 1) ? 1 : t;
  104 }
  105 
  106 static void
  107 amrr_init(struct ieee80211vap *vap)
  108 {
  109         struct ieee80211_amrr *amrr;
  110 
  111         KASSERT(vap->iv_rs == NULL, ("%s called multiple times", __func__));
  112 
  113         amrr = vap->iv_rs = malloc(sizeof(struct ieee80211_amrr),
  114             M_80211_RATECTL, M_NOWAIT|M_ZERO);
  115         if (amrr == NULL) {
  116                 if_printf(vap->iv_ifp, "couldn't alloc ratectl structure\n");
  117                 return;
  118         }
  119         amrr->amrr_min_success_threshold = IEEE80211_AMRR_MIN_SUCCESS_THRESHOLD;
  120         amrr->amrr_max_success_threshold = IEEE80211_AMRR_MAX_SUCCESS_THRESHOLD;
  121         amrr_setinterval(vap, 500 /* ms */);
  122         amrr_sysctlattach(vap, vap->iv_sysctl, vap->iv_oid);
  123 }
  124 
  125 static void
  126 amrr_deinit(struct ieee80211vap *vap)
  127 {
  128         free(vap->iv_rs, M_80211_RATECTL);
  129 }
  130 
  131 static void
  132 amrr_node_init(struct ieee80211_node *ni)
  133 {
  134         const struct ieee80211_rateset *rs = &ni->ni_rates;
  135         struct ieee80211vap *vap = ni->ni_vap;
  136         struct ieee80211_amrr *amrr = vap->iv_rs;
  137         struct ieee80211_amrr_node *amn;
  138 
  139         if (ni->ni_rctls == NULL) {
  140                 ni->ni_rctls = amn = malloc(sizeof(struct ieee80211_amrr_node),
  141                     M_80211_RATECTL, M_NOWAIT|M_ZERO);
  142                 if (amn == NULL) {
  143                         if_printf(vap->iv_ifp, "couldn't alloc per-node ratectl "
  144                             "structure\n");
  145                         return;
  146                 }
  147         } else
  148                 amn = ni->ni_rctls;
  149         amn->amn_amrr = amrr;
  150         amn->amn_success = 0;
  151         amn->amn_recovery = 0;
  152         amn->amn_txcnt = amn->amn_retrycnt = 0;
  153         amn->amn_success_threshold = amrr->amrr_min_success_threshold;
  154 
  155         /* pick initial rate */
  156         for (amn->amn_rix = rs->rs_nrates - 1;
  157              amn->amn_rix > 0 && (rs->rs_rates[amn->amn_rix] & IEEE80211_RATE_VAL) > 72;
  158              amn->amn_rix--)
  159                 ;
  160         ni->ni_txrate = rs->rs_rates[amn->amn_rix] & IEEE80211_RATE_VAL;
  161         amn->amn_ticks = ticks;
  162 
  163         IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
  164             "AMRR initial rate %d", ni->ni_txrate);
  165 }
  166 
  167 static void
  168 amrr_node_deinit(struct ieee80211_node *ni)
  169 {
  170         free(ni->ni_rctls, M_80211_RATECTL);
  171 }
  172 
  173 static int
  174 amrr_update(struct ieee80211_amrr *amrr, struct ieee80211_amrr_node *amn,
  175     struct ieee80211_node *ni)
  176 {
  177         int rix = amn->amn_rix;
  178 
  179         KASSERT(is_enough(amn), ("txcnt %d", amn->amn_txcnt));
  180 
  181         if (is_success(amn)) {
  182                 amn->amn_success++;
  183                 if (amn->amn_success >= amn->amn_success_threshold &&
  184                     rix + 1 < ni->ni_rates.rs_nrates) {
  185                         amn->amn_recovery = 1;
  186                         amn->amn_success = 0;
  187                         rix++;
  188                         IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
  189                             "AMRR increasing rate %d (txcnt=%d retrycnt=%d)",
  190                             ni->ni_rates.rs_rates[rix] & IEEE80211_RATE_VAL,
  191                             amn->amn_txcnt, amn->amn_retrycnt);
  192                 } else {
  193                         amn->amn_recovery = 0;
  194                 }
  195         } else if (is_failure(amn)) {
  196                 amn->amn_success = 0;
  197                 if (rix > 0) {
  198                         if (amn->amn_recovery) {
  199                                 amn->amn_success_threshold *= 2;
  200                                 if (amn->amn_success_threshold >
  201                                     amrr->amrr_max_success_threshold)
  202                                         amn->amn_success_threshold =
  203                                             amrr->amrr_max_success_threshold;
  204                         } else {
  205                                 amn->amn_success_threshold =
  206                                     amrr->amrr_min_success_threshold;
  207                         }
  208                         rix--;
  209                         IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_RATECTL, ni,
  210                             "AMRR decreasing rate %d (txcnt=%d retrycnt=%d)",
  211                             ni->ni_rates.rs_rates[rix] & IEEE80211_RATE_VAL,
  212                             amn->amn_txcnt, amn->amn_retrycnt);
  213                 }
  214                 amn->amn_recovery = 0;
  215         }
  216 
  217         /* reset counters */
  218         amn->amn_txcnt = 0;
  219         amn->amn_retrycnt = 0;
  220 
  221         return rix;
  222 }
  223 
  224 /*
  225  * Return the rate index to use in sending a data frame.
  226  * Update our internal state if it's been long enough.
  227  * If the rate changes we also update ni_txrate to match.
  228  */
  229 static int
  230 amrr_rate(struct ieee80211_node *ni, void *arg __unused, uint32_t iarg __unused)
  231 {
  232         struct ieee80211_amrr_node *amn = ni->ni_rctls;
  233         struct ieee80211_amrr *amrr = amn->amn_amrr;
  234         int rix;
  235 
  236         if (is_enough(amn) && (ticks - amn->amn_ticks) > amrr->amrr_interval) {
  237                 rix = amrr_update(amrr, amn, ni);
  238                 if (rix != amn->amn_rix) {
  239                         /* update public rate */
  240                         ni->ni_txrate =
  241                             ni->ni_rates.rs_rates[rix] & IEEE80211_RATE_VAL;
  242                         amn->amn_rix = rix;
  243                 }
  244                 amn->amn_ticks = ticks;
  245         } else
  246                 rix = amn->amn_rix;
  247         return rix;
  248 }
  249 
  250 /*
  251  * Update statistics with tx complete status.  Ok is non-zero
  252  * if the packet is known to be ACK'd.  Retries has the number
  253  * retransmissions (i.e. xmit attempts - 1).
  254  */
  255 static void
  256 amrr_tx_complete(const struct ieee80211vap *vap,
  257     const struct ieee80211_node *ni, int ok,
  258     void *arg1, void *arg2 __unused)
  259 {
  260         struct ieee80211_amrr_node *amn = ni->ni_rctls;
  261         int retries = *(int *)arg1;
  262 
  263         amn->amn_txcnt++;
  264         if (ok)
  265                 amn->amn_success++;
  266         amn->amn_retrycnt += retries;
  267 }
  268 
  269 /*
  270  * Set tx count/retry statistics explicitly.  Intended for
  271  * drivers that poll the device for statistics maintained
  272  * in the device.
  273  */
  274 static void
  275 amrr_tx_update(const struct ieee80211vap *vap, const struct ieee80211_node *ni,
  276     void *arg1, void *arg2, void *arg3)
  277 {
  278         struct ieee80211_amrr_node *amn = ni->ni_rctls;
  279         int txcnt = *(int *)arg1, success = *(int *)arg2, retrycnt = *(int *)arg3;
  280 
  281         amn->amn_txcnt = txcnt;
  282         amn->amn_success = success;
  283         amn->amn_retrycnt = retrycnt;
  284 }
  285 
  286 static int
  287 amrr_sysctl_interval(SYSCTL_HANDLER_ARGS)
  288 {
  289         struct ieee80211vap *vap = arg1;
  290         struct ieee80211_amrr *amrr = vap->iv_rs;
  291         int msecs = ticks_to_msecs(amrr->amrr_interval);
  292         int error;
  293 
  294         error = sysctl_handle_int(oidp, &msecs, 0, req);
  295         if (error || !req->newptr)
  296                 return error;
  297         amrr_setinterval(vap, msecs);
  298         return 0;
  299 }
  300 
  301 static void
  302 amrr_sysctlattach(struct ieee80211vap *vap,
  303     struct sysctl_ctx_list *ctx, struct sysctl_oid *tree)
  304 {
  305         struct ieee80211_amrr *amrr = vap->iv_rs;
  306 
  307         SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
  308             "amrr_rate_interval", CTLTYPE_INT | CTLFLAG_RW, vap,
  309             0, amrr_sysctl_interval, "I", "amrr operation interval (ms)");
  310         /* XXX bounds check values */
  311         SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
  312             "amrr_max_sucess_threshold", CTLFLAG_RW,
  313             &amrr->amrr_max_success_threshold, 0, "");
  314         SYSCTL_ADD_UINT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
  315             "amrr_min_sucess_threshold", CTLFLAG_RW,
  316             &amrr->amrr_min_success_threshold, 0, "");
  317 }

Cache object: 623f6312b37e4051dabb43e789d180c4


[ 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.