package/kernel/mac80211/patches/subsys/327-mac80211-extend-AQL-aggregation-estimation-to-HE-and.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Date: Thu, 27 Aug 2020 12:44:36 +0200
   3 Subject: [PATCH] mac80211: extend AQL aggregation estimation to HE and fix
   4  unit mismatch
   5
   6 The unit of the return value of ieee80211_get_rate_duration is nanoseconds, not
   7 milliseconds. Adjust the duration checks to account for that.
   8 For higher data rates, allow larger estimated aggregation sizes, and add some
   9 values for HE as well, which can use much larger aggregates.
  10 Since small packets with high data rates can now lead to duration values too
  11 small for info->tx_time_est, return a minimum of 4us.
  12
  13 Signed-off-by: Felix Fietkau <nbd@nbd.name>
  14 ---
  15
  16 --- a/net/mac80211/airtime.c
  17 +++ b/net/mac80211/airtime.c
  18 @@ -668,20 +668,26 @@ u32 ieee80211_calc_expected_tx_airtime(s
  19                  * This will not be very accurate, but much better than simply
  20                  * assuming un-aggregated tx in all cases.
  21                  */
  22 -               if (duration > 400) /* <= VHT20 MCS2 1S */
  23 +               if (duration > 400 * 1024) /* <= VHT20 MCS2 1S */
  24                         agg_shift = 1;
  25 -               else if (duration > 250) /* <= VHT20 MCS3 1S or MCS1 2S */
  26 +               else if (duration > 250 * 1024) /* <= VHT20 MCS3 1S or MCS1 2S */
  27                         agg_shift = 2;
  28 -               else if (duration > 150) /* <= VHT20 MCS5 1S or MCS3 2S */
  29 +               else if (duration > 150 * 1024) /* <= VHT20 MCS5 1S or MCS2 2S */
  30                         agg_shift = 3;
  31 -               else
  32 +               else if (duration > 70 * 1024) /* <= VHT20 MCS5 2S */
  33                         agg_shift = 4;
  34 +               else if (stat.encoding != RX_ENC_HE ||
  35 +                        duration > 20 * 1024) /* <= HE40 MCS6 2S */
  36 +                       agg_shift = 5;
  37 +               else
  38 +                       agg_shift = 6;
  39
  40                 duration *= len;
  41                 duration /= AVG_PKT_SIZE;
  42                 duration /= 1024;
  43 +               duration += (overhead >> agg_shift);
  44
  45 -               return duration + (overhead >> agg_shift);
  46 +               return max_t(u32, duration, 4);
  47         }
  48
  49         if (!conf)