rt2870_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 "rt2870_amrr.h"
  31
  32 /*
  33  * Defines and macros
  34  */
  35
  36 #define RT2870_AMRR_IS_SUCCESS(amrr_node)                               ((amrr_node)->retrycnt < (amrr_node)->txcnt / 10)
  37
  38 #define RT2870_AMRR_IS_FAILURE(amrr_node)                               ((amrr_node)->retrycnt > (amrr_node)->txcnt / 3)
  39
  40 #define RT2870_AMRR_IS_ENOUGH(amrr_node)                                ((amrr_node)->txcnt > 10)
  41
  42 /*
  43  * Static function prototypes
  44  */
  45
  46 static int rt2870_amrr_update(struct rt2870_amrr *amrr,
  47         struct rt2870_amrr_node *amrr_node, struct ieee80211_node *ni);
  48
  49 /*
  50  * rt2870_amrr_init
  51  */
  52 void rt2870_amrr_init(struct rt2870_amrr *amrr, struct ieee80211vap *vap,
  53         int ntxpath, int min_success_threshold, int max_success_threshold, int msecs)
  54 {
  55         int t;
  56
  57         amrr->ntxpath = ntxpath;
  58
  59         amrr->min_success_threshold = min_success_threshold;
  60         amrr->max_success_threshold = max_success_threshold;
  61
  62         if (msecs < 100)
  63                 msecs = 100;
  64
  65         t = msecs_to_ticks(msecs);
  66
  67         amrr->interval = (t < 1) ? 1 : t;
  68 }
  69
  70 /*
  71  * rt2870_amrr_cleanup
  72  */
  73 void rt2870_amrr_cleanup(struct rt2870_amrr *amrr)
  74 {
  75 }
  76
  77 /*
  78  * rt2870_amrr_node_init
  79  */
  80 void rt2870_amrr_node_init(struct rt2870_amrr *amrr,
  81     struct rt2870_amrr_node *amrr_node, struct ieee80211_node *ni)
  82 {
  83         const struct ieee80211_rateset *rs;
  84
  85         amrr_node->amrr = amrr;
  86         amrr_node->success = 0;
  87         amrr_node->recovery = 0;
  88         amrr_node->txcnt = 0;
  89         amrr_node->retrycnt = 0;
  90         amrr_node->success_threshold = amrr->min_success_threshold;
  91
  92         if (ni->ni_flags & IEEE80211_NODE_HT)
  93         {
  94                 rs = (const struct ieee80211_rateset *) &ni->ni_htrates;
  95
  96                 for (amrr_node->rate_index = rs->rs_nrates - 1;
  97                         amrr_node->rate_index > 0 && (rs->rs_rates[amrr_node->rate_index] & IEEE80211_RATE_VAL) > 4;
  98                         amrr_node->rate_index--) ;
  99
 100                 ni->ni_txrate = rs->rs_rates[amrr_node->rate_index] | IEEE80211_RATE_MCS;
 101         }
 102         else
 103         {
 104                 rs = &ni->ni_rates;
 105
 106                 for (amrr_node->rate_index = rs->rs_nrates - 1;
 107                         amrr_node->rate_index > 0 && (rs->rs_rates[amrr_node->rate_index] & IEEE80211_RATE_VAL) > 72;
 108                         amrr_node->rate_index--) ;
 109
 110                 ni->ni_txrate = rs->rs_rates[amrr_node->rate_index] & IEEE80211_RATE_VAL;
 111         }
 112
 113         amrr_node->ticks = ticks;
 114 }
 115
 116 /*
 117  * rt2870_amrr_choose
 118  */
 119 int rt2870_amrr_choose(struct ieee80211_node *ni,
 120         struct rt2870_amrr_node *amrr_node)
 121 {
 122         struct rt2870_amrr *amrr;
 123         int rate_index;
 124
 125         amrr = amrr_node->amrr;
 126
 127         if (RT2870_AMRR_IS_ENOUGH(amrr_node) &&
 128                 (ticks - amrr_node->ticks) > amrr->interval)
 129         {
 130                 rate_index = rt2870_amrr_update(amrr, amrr_node, ni);
 131                 if (rate_index != amrr_node->rate_index)
 132                 {
 133                         if (ni->ni_flags & IEEE80211_NODE_HT)
 134                                 ni->ni_txrate = ni->ni_htrates.rs_rates[rate_index] | IEEE80211_RATE_MCS;
 135                         else
 136                                 ni->ni_txrate = ni->ni_rates.rs_rates[rate_index] & IEEE80211_RATE_VAL;
 137
 138                         amrr_node->rate_index = rate_index;
 139                 }
 140
 141                 amrr_node->ticks = ticks;
 142         }
 143         else
 144         {
 145                 rate_index = amrr_node->rate_index;
 146         }
 147
 148         return rate_index;
 149 }
 150
 151 /*
 152  * rt2870_amrr_update
 153  */
 154 static int rt2870_amrr_update(struct rt2870_amrr *amrr,
 155         struct rt2870_amrr_node *amrr_node, struct ieee80211_node *ni)
 156 {
 157         const struct ieee80211_rateset *rs;
 158         int rate_index;
 159
 160         KASSERT(RT2860_AMRR_IS_ENOUGH(amrr_node),
 161                 ("not enough Tx count: txcnt=%d",
 162                  amrr_node->txcnt));
 163
 164         if (ni->ni_flags & IEEE80211_NODE_HT)
 165                 rs = (const struct ieee80211_rateset *) &ni->ni_htrates;
 166         else
 167                 rs = &ni->ni_rates;
 168
 169         rate_index = amrr_node->rate_index;
 170
 171         if (RT2870_AMRR_IS_SUCCESS(amrr_node))
 172         {
 173                 amrr_node->success++;
 174                 if ((amrr_node->success >= amrr_node->success_threshold) &&
 175                     (rate_index + 1 < rs->rs_nrates) &&
 176                         (!(ni->ni_flags & IEEE80211_NODE_HT) || (rs->rs_rates[rate_index + 1] & IEEE80211_RATE_VAL) < (amrr->ntxpath * 8)))
 177                 {
 178                         amrr_node->recovery = 1;
 179                         amrr_node->success = 0;
 180
 181                         rate_index++;
 182                 }
 183                 else
 184                 {
 185                         amrr_node->recovery = 0;
 186                 }
 187         }
 188         else if (RT2870_AMRR_IS_FAILURE(amrr_node))
 189         {
 190                 amrr_node->success = 0;
 191
 192                 if (rate_index > 0)
 193                 {
 194                         if (amrr_node->recovery)
 195                         {
 196                                 amrr_node->success_threshold *= 2;
 197                                 if (amrr_node->success_threshold > amrr->max_success_threshold)
 198                                         amrr_node->success_threshold = amrr->max_success_threshold;
 199                         }
 200                         else
 201                         {
 202                                 amrr_node->success_threshold = amrr->min_success_threshold;
 203                         }
 204
 205                         rate_index--;
 206                 }
 207
 208                 amrr_node->recovery = 0;
 209         }
 210
 211         amrr_node->txcnt = 0;
 212         amrr_node->retrycnt = 0;
 213
 214         return rate_index;
 215 }