rt2860_amrr.c

   1
   2 /*-
   3  * Copyright (c) 2009-2010 Alexander Egorenkov <egorenar@gmail.com>
   4  * Copyright (c) 2009 Damien Bergamini <damien.bergamini@free.fr>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <sys/param.h>
  20 #include <sys/kernel.h>
  21 #include <sys/module.h>
  22 #include <sys/socket.h>
  23 #include <sys/sysctl.h>
  24
  25 #include <net/if.h>
  26 #include <net/if_media.h>
  27
  28 #include <net80211/ieee80211_var.h>
  29
  30 #include "rt2860_amrr.h"
  31
  32 /*
  33  * Defines and macros
  34  */
  35
  36 #define RT2860_AMRR_IS_SUCCESS(amrr_node)                               ((amrr_node)->retrycnt < (amrr_node)->txcnt / 10)
  37
  38 #define RT2860_AMRR_IS_FAILURE(amrr_node)                               ((amrr_node)->retrycnt > (amrr_node)->txcnt / 3)
  39
  40 #define RT2860_AMRR_IS_ENOUGH(amrr_node)                                ((amrr_node)->txcnt > 10)
  41
  42 /*
  43  * Static function prototypes
  44  */
  45
  46 static int rt2860_amrr_update(struct rt2860_amrr *amrr,
  47         struct rt2860_amrr_node *amrr_node, struct ieee80211_node *ni);
  48
  49 /*
  50  * rt2860_amrr_init
  51  */
  52 void rt2860_amrr_init(struct rt2860_amrr *amrr, struct ieee80211com *ic,
  53         int min_success_threshold, int max_success_threshold, int msecs)
  54 {
  55         int t;
  56
  57         amrr->min_success_threshold = min_success_threshold;
  58         amrr->max_success_threshold = max_success_threshold;
  59
  60         if (msecs < 100)
  61                 msecs = 100;
  62
  63         t = msecs_to_ticks(msecs);
  64
  65         amrr->interval = (t < 1) ? 1 : t;
  66 }
  67
  68 /*
  69  * rt2860_amrr_cleanup
  70  */
  71 void rt2860_amrr_cleanup(struct rt2860_amrr *amrr)
  72 {
  73 }
  74
  75 /*
  76  * rt2860_amrr_node_init
  77  */
  78 void rt2860_amrr_node_init(struct rt2860_amrr *amrr,
  79     struct rt2860_amrr_node *amrr_node, struct ieee80211_node *ni)
  80 {
  81         const struct ieee80211_rateset *rs;
  82
  83         amrr_node->amrr = amrr;
  84         amrr_node->success = 0;
  85         amrr_node->recovery = 0;
  86         amrr_node->txcnt = 0;
  87         amrr_node->retrycnt = 0;
  88         amrr_node->success_threshold = amrr->min_success_threshold;
  89
  90         if (ni->ni_flags & IEEE80211_NODE_HT)
  91         {
  92                 rs = (const struct ieee80211_rateset *) &ni->ni_htrates;
  93
  94                 for (ni->ni_txrate = rs->rs_nrates - 1;
  95                         ni->ni_txrate > 0 && rs->rs_rates[ni->ni_txrate] > 4;
  96                         ni->ni_txrate--) ;
  97         }
  98         else
  99         {
 100                 rs = &ni->ni_rates;
 101
 102                 for (ni->ni_txrate = rs->rs_nrates - 1;
 103                         ni->ni_txrate > 0 && (rs->rs_rates[ni->ni_txrate] & IEEE80211_RATE_VAL) > 72;
 104                         ni->ni_txrate--) ;
 105         }
 106
 107         amrr_node->ticks = ticks;
 108 }
 109
 110 /*
 111  * rt2860_amrr_choose
 112  */
 113 int rt2860_amrr_choose(struct ieee80211_node *ni,
 114         struct rt2860_amrr_node *amrr_node)
 115 {
 116         struct rt2860_amrr *amrr;
 117         int rate_index;
 118
 119         amrr = amrr_node->amrr;
 120
 121         if (RT2860_AMRR_IS_ENOUGH(amrr_node) &&
 122                 (ticks - amrr_node->ticks) > amrr->interval)
 123         {
 124                 rate_index = rt2860_amrr_update(amrr, amrr_node, ni);
 125                 if (rate_index != ni->ni_txrate)
 126                         ni->ni_txrate = rate_index;
 127
 128                 amrr_node->ticks = ticks;
 129         }
 130         else
 131         {
 132                 rate_index = ni->ni_txrate;
 133         }
 134
 135         return rate_index;
 136 }
 137
 138 /*
 139  * rt2860_amrr_update
 140  */
 141 static int rt2860_amrr_update(struct rt2860_amrr *amrr,
 142         struct rt2860_amrr_node *amrr_node, struct ieee80211_node *ni)
 143 {
 144         const struct ieee80211_rateset *rs;
 145         int rate_index;
 146
 147         KASSERT(RT2860_AMRR_IS_ENOUGH(amrr_node),
 148                 ("not enough Tx count: txcnt=%d",
 149                  amrr_node->txcnt));
 150
 151         if (ni->ni_flags & IEEE80211_NODE_HT)
 152                 rs = (const struct ieee80211_rateset *) &ni->ni_htrates;
 153         else
 154                 rs = &ni->ni_rates;
 155
 156         rate_index = ni->ni_txrate;
 157
 158         if (RT2860_AMRR_IS_SUCCESS(amrr_node))
 159         {
 160                 amrr_node->success++;
 161                 if ((amrr_node->success >= amrr_node->success_threshold) &&
 162                     (rate_index + 1 < rs->rs_nrates))
 163                 {
 164                         amrr_node->recovery = 1;
 165                         amrr_node->success = 0;
 166
 167                         rate_index++;
 168                 }
 169                 else
 170                 {
 171                         amrr_node->recovery = 0;
 172                 }
 173         }
 174         else if (RT2860_AMRR_IS_FAILURE(amrr_node))
 175         {
 176                 amrr_node->success = 0;
 177
 178                 if (rate_index > 0)
 179                 {
 180                         if (amrr_node->recovery)
 181                         {
 182                                 amrr_node->success_threshold *= 2;
 183                                 if (amrr_node->success_threshold > amrr->max_success_threshold)
 184                                         amrr_node->success_threshold = amrr->max_success_threshold;
 185                         }
 186                         else
 187                         {
 188                                 amrr_node->success_threshold = amrr->min_success_threshold;
 189                         }
 190
 191                         rate_index--;
 192                 }
 193
 194                 amrr_node->recovery = 0;
 195         }
 196
 197         amrr_node->txcnt = 0;
 198         amrr_node->retrycnt = 0;
 199
 200         return rate_index;
 201 }