sys/net80211/ieee80211_amrr.c

   1 /*      $NetBSD: ieee80211_amrr.c,v 1.1 2006/10/31 21:53:41 joerg Exp $ */
   2 /*      $OpenBSD: ieee80211_amrr.c,v 1.1 2006/06/17 19:07:19 damien Exp $       */
   3
   4 /*-
   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 __KERNEL_RCSID(0, "$NetBSD$");
  23
  24 #include <sys/param.h>
  25 #include <sys/kernel.h>
  26 #include <sys/socket.h>
  27 #include <sys/sysctl.h>
  28
  29 #include <net/if.h>
  30 #include <net/if_media.h>
  31
  32 #ifdef INET
  33 #include <netinet/in.h>
  34 #include <netinet/if_ether.h>
  35 #endif
  36
  37 #include <net80211/ieee80211.h>
  38 #include <net80211/ieee80211_var.h>
  39 #include <net80211/ieee80211_amrr.h>
  40
  41 #define is_success(amn) \
  42         ((amn)->amn_retrycnt < (amn)->amn_txcnt / 10)
  43 #define is_failure(amn) \
  44         ((amn)->amn_retrycnt > (amn)->amn_txcnt / 3)
  45 #define is_enough(amn)          \
  46         ((amn)->amn_txcnt > 10)
  47 #define is_min_rate(ni)         \
  48         ((ni)->ni_txrate == 0)
  49 #define is_max_rate(ni)         \
  50         ((ni)->ni_txrate == (ni)->ni_rates.rs_nrates - 1)
  51 #define increase_rate(ni)       \
  52         ((ni)->ni_txrate++)
  53 #define decrease_rate(ni)       \
  54         ((ni)->ni_txrate--)
  55 #define reset_cnt(amn)          \
  56         do { (amn)->amn_txcnt = (amn)->amn_retrycnt = 0; } while (0)
  57
  58 void
  59 ieee80211_amrr_node_init(struct ieee80211_amrr *amrr,
  60     struct ieee80211_amrr_node *amn)
  61 {
  62         amn->amn_success = 0;
  63         amn->amn_recovery = 0;
  64         amn->amn_txcnt = amn->amn_retrycnt = 0;
  65         amn->amn_success_threshold = amrr->amrr_min_success_threshold;
  66 }
  67
  68 /*
  69  * Update ni->ni_txrate.
  70  */
  71 void
  72 ieee80211_amrr_choose(struct ieee80211_amrr *amrr, struct ieee80211_node *ni,
  73     struct ieee80211_amrr_node *amn)
  74 {
  75         int need_change = 0;
  76
  77         if (is_success(amn) && is_enough(amn)) {
  78                 amn->amn_success++;
  79                 if (amn->amn_success >= amn->amn_success_threshold &&
  80                     !is_max_rate(ni)) {
  81                         amn->amn_recovery = 1;
  82                         amn->amn_success = 0;
  83                         increase_rate(ni);
  84                         IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_DEBUG,
  85                             "AMRR increasing rate %d (txcnt=%d retrycnt=%d)\n",
  86                             ni->ni_rates.rs_rates[ni->ni_txrate] &
  87                                 IEEE80211_RATE_VAL,
  88                             amn->amn_txcnt, amn->amn_retrycnt);
  89                         need_change = 1;
  90                 } else {
  91                         amn->amn_recovery = 0;
  92                 }
  93         } else if (is_failure(amn)) {
  94                 amn->amn_success = 0;
  95                 if (!is_min_rate(ni)) {
  96                         if (amn->amn_recovery) {
  97                                 amn->amn_success_threshold *= 2;
  98                                 if (amn->amn_success_threshold >
  99                                     amrr->amrr_max_success_threshold)
 100                                         amn->amn_success_threshold =
 101                                             amrr->amrr_max_success_threshold;
 102                         } else {
 103                                 amn->amn_success_threshold =
 104                                     amrr->amrr_min_success_threshold;
 105                         }
 106                         decrease_rate(ni);
 107                         IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_DEBUG,
 108                             "AMRR decreasing rate %d (txcnt=%d retrycnt=%d)\n",
 109                             ni->ni_rates.rs_rates[ni->ni_txrate] &
 110                                 IEEE80211_RATE_VAL,
 111                             amn->amn_txcnt, amn->amn_retrycnt);
 112                         need_change = 1;
 113                 }
 114                 amn->amn_recovery = 0;
 115         }
 116
 117         if (is_enough(amn) || need_change)
 118                 reset_cnt(amn);
 119 }