kernel/net/net80211/net80211_amrr.c

   1 /*      $NetBSD: ieee80211_amrr.c,v 1.2 2007/12/11 12:40:10 lukem Exp $ */
   2 /*      $OpenBSD: ieee80211_amrr.c,v 1.1 2006/06/17 19:07:19 damien Exp $ */
   3
   4 /*
   5  * Copyright 2016 Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
   6  */
   7
   8 /*
   9  * Copyright (c) 2006
  10  *      Damien Bergamini <damien.bergamini@free.fr>
  11  *
  12  * Permission to use, copy, modify, and distribute this software for any
  13  * purpose with or without fee is hereby granted, provided that the above
  14  * copyright notice and this permission notice appear in all copies.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  17  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  18  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  19  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  20  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  21  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  22  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  23  */
  24
  25 #include <sys/param.h>
  26 #include <sys/socket.h>
  27 #include <sys/sdt.h>
  28
  29 #include <net/if.h>
  30
  31 #include <sys/net80211.h>
  32 #include <sys/net80211_amrr.h>
  33 #include "net80211_impl.h"
  34
  35 #define is_success(amn) \
  36         ((amn)->amn_retrycnt < (amn)->amn_txcnt / 10)
  37 #define is_failure(amn) \
  38         ((amn)->amn_retrycnt > (amn)->amn_txcnt / 3)
  39 #define is_enough(amn)          \
  40         ((amn)->amn_txcnt > 10)
  41 #define is_min_rate(ni)         \
  42         ((ni)->in_txrate == 0)
  43 #define is_max_rate(ni)         \
  44         ((ni)->in_txrate == (ni)->in_rates.ir_nrates - 1)
  45 #define increase_rate(ni)       \
  46         ((ni)->in_txrate++)
  47 #define decrease_rate(ni)       \
  48         ((ni)->in_txrate--)
  49 #define reset_cnt(amn)          \
  50         do { (amn)->amn_txcnt = (amn)->amn_retrycnt = 0; \
  51         _NOTE(CONSTCOND) } while (0)
  52
  53 void
  54 ieee80211_amrr_node_init(struct ieee80211_amrr *amrr,
  55     struct ieee80211_amrr_node *amn)
  56 {
  57         amn->amn_success = 0;
  58         amn->amn_recovery = 0;
  59         amn->amn_txcnt = amn->amn_retrycnt = 0;
  60         amn->amn_success_threshold = amrr->amrr_min_success_threshold;
  61 }
  62
  63 /*
  64  * Update ni->in_txrate.
  65  */
  66 void
  67 ieee80211_amrr_choose(struct ieee80211_amrr *amrr, struct ieee80211_node *ni,
  68     struct ieee80211_amrr_node *amn)
  69 {
  70         int need_change = 0;
  71         uint8_t rate;
  72
  73         if (is_success(amn) && is_enough(amn)) {
  74                 amn->amn_success++;
  75                 if (amn->amn_success >= amn->amn_success_threshold &&
  76                     !is_max_rate(ni)) {
  77                         amn->amn_recovery = 1;
  78                         amn->amn_success = 0;
  79                         increase_rate(ni);
  80                         rate = ni->in_rates.ir_rates[ni->in_txrate] &
  81                             IEEE80211_RATE_VAL;
  82                         ieee80211_dbg(IEEE80211_MSG_XRATE,
  83                             "AMRR increasing rate %d (txcnt=%d retrycnt=%d)",
  84                             rate, amn->amn_txcnt, amn->amn_retrycnt);
  85                         DTRACE_PROBE4(amrr__increase__rate,
  86                             struct ieee80211_node *, ni,
  87                             uint8_t, rate,
  88                             uint_t, amn->amn_txcnt,
  89                             uint_t, amn->amn_retrycnt);
  90                         need_change = 1;
  91                 } else {
  92                         amn->amn_recovery = 0;
  93                 }
  94         } else if (is_failure(amn)) {
  95                 amn->amn_success = 0;
  96                 if (!is_min_rate(ni)) {
  97                         if (amn->amn_recovery) {
  98                                 amn->amn_success_threshold *= 2;
  99                                 if (amn->amn_success_threshold >
 100                                     amrr->amrr_max_success_threshold)
 101                                         amn->amn_success_threshold =
 102                                             amrr->amrr_max_success_threshold;
 103                         } else {
 104                                 amn->amn_success_threshold =
 105                                     amrr->amrr_min_success_threshold;
 106                         }
 107                         decrease_rate(ni);
 108                         rate = ni->in_rates.ir_rates[ni->in_txrate] &
 109                             IEEE80211_RATE_VAL;
 110                         ieee80211_dbg(IEEE80211_MSG_XRATE,
 111                             "AMRR decreasing rate %d (txcnt=%d retrycnt=%d)",
 112                             rate, amn->amn_txcnt, amn->amn_retrycnt);
 113                         DTRACE_PROBE4(amrr__decrease__rate,
 114                             struct ieee80211_node *, ni,
 115                             uint8_t, rate,
 116                             uint_t, amn->amn_txcnt,
 117                             uint_t, amn->amn_retrycnt);
 118                         need_change = 1;
 119                 }
 120                 amn->amn_recovery = 0;
 121         }
 122
 123         if (is_enough(amn) || need_change)
 124                 reset_cnt(amn);
 125 }