package/kernel/mac80211/patches/subsys/341-mac80211-minstrel_ht-improve-ampdu-length-estimation.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Date: Sat, 26 Dec 2020 19:08:19 +0100
   3 Subject: [PATCH] mac80211: minstrel_ht: improve ampdu length estimation
   4
   5 If the driver does not report A-MPDU length, estimate it based on the rate.
   6
   7 Signed-off-by: Felix Fietkau <nbd@nbd.name>
   8 ---
   9
  10 --- a/net/mac80211/rc80211_minstrel_ht.c
  11 +++ b/net/mac80211/rc80211_minstrel_ht.c
  12 @@ -382,13 +382,37 @@ minstrel_get_ratestats(struct minstrel_h
  13         return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES];
  14  }
  15
  16 +static inline int
  17 +minstrel_get_duration(int index)
  18 +{
  19 +       const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
  20 +       unsigned int duration = group->duration[index % MCS_GROUP_RATES];
  21 +       return duration << group->shift;
  22 +}
  23 +
  24  static unsigned int
  25  minstrel_ht_avg_ampdu_len(struct minstrel_ht_sta *mi)
  26  {
  27 -       if (!mi->avg_ampdu_len)
  28 -               return AVG_AMPDU_SIZE;
  29 +       int duration;
  30
  31 -       return MINSTREL_TRUNC(mi->avg_ampdu_len);
  32 +       if (mi->avg_ampdu_len)
  33 +               return MINSTREL_TRUNC(mi->avg_ampdu_len);
  34 +
  35 +       if (minstrel_ht_is_legacy_group(mi->max_tp_rate[0] / MCS_GROUP_RATES))
  36 +               return 1;
  37 +
  38 +       duration = minstrel_get_duration(mi->max_tp_rate[0]);
  39 +
  40 +       if (duration > 400 * 1000)
  41 +               return 2;
  42 +
  43 +       if (duration > 250 * 1000)
  44 +               return 4;
  45 +
  46 +       if (duration > 150 * 1000)
  47 +               return 8;
  48 +
  49 +       return 16;
  50  }
  51
  52  /*
  53 @@ -588,14 +612,6 @@ minstrel_ht_prob_rate_reduce_streams(str
  54         }
  55  }
  56
  57 -static inline int
  58 -minstrel_get_duration(int index)
  59 -{
  60 -       const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
  61 -       unsigned int duration = group->duration[index % MCS_GROUP_RATES];
  62 -       return duration << group->shift;
  63 -}
  64 -
  65  static bool
  66  minstrel_ht_probe_group(struct minstrel_ht_sta *mi, const struct mcs_group *tp_group,
  67                                                 int tp_idx, const struct mcs_group *group)