package/kernel/mac80211/patches/subsys/312-mac80211-minstrel_ht-add-flag-to-indicate-missing-in.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Date: Wed, 16 Jan 2019 22:32:12 +0100
   3 Subject: [PATCH] mac80211: minstrel_ht: add flag to indicate
   4  missing/inaccurate tx A-MPDU length
   5
   6 Some hardware (e.g. MediaTek MT7603) cannot report A-MPDU length in tx status
   7 information. Add support for a flag to indicate that, to allow minstrel_ht
   8 to use a fixed value in its internal calculation (which gives better results
   9 than just defaulting to 1).
  10
  11 Signed-off-by: Felix Fietkau <nbd@nbd.name>
  12 Signed-off-by: Johannes Berg <johannes.berg@intel.com>
  13 ---
  14
  15 --- a/include/net/mac80211.h
  16 +++ b/include/net/mac80211.h
  17 @@ -2131,6 +2131,9 @@ struct ieee80211_txq {
  18   * @IEEE80211_HW_DOESNT_SUPPORT_QOS_NDP: The driver (or firmware) doesn't
  19   *     support QoS NDP for AP probing - that's most likely a driver bug.
  20   *
  21 + * @IEEE80211_HW_TX_STATUS_NO_AMPDU_LEN: Driver does not report accurate A-MPDU
  22 + *     length in tx status information
  23 + *
  24   * @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays
  25   */
  26  enum ieee80211_hw_flags {
  27 @@ -2176,6 +2179,7 @@ enum ieee80211_hw_flags {
  28         IEEE80211_HW_SUPPORTS_TDLS_BUFFER_STA,
  29         IEEE80211_HW_DEAUTH_NEED_MGD_TX_PREP,
  30         IEEE80211_HW_DOESNT_SUPPORT_QOS_NDP,
  31 +       IEEE80211_HW_TX_STATUS_NO_AMPDU_LEN,
  32
  33         /* keep last, obviously */
  34         NUM_IEEE80211_HW_FLAGS
  35 --- a/net/mac80211/debugfs.c
  36 +++ b/net/mac80211/debugfs.c
  37 @@ -214,6 +214,7 @@ static const char *hw_flag_names[] = {
  38         FLAG(SUPPORTS_TDLS_BUFFER_STA),
  39         FLAG(DEAUTH_NEED_MGD_TX_PREP),
  40         FLAG(DOESNT_SUPPORT_QOS_NDP),
  41 +       FLAG(TX_STATUS_NO_AMPDU_LEN),
  42  #undef FLAG
  43  };
  44
  45 --- a/net/mac80211/rc80211_minstrel_ht.c
  46 +++ b/net/mac80211/rc80211_minstrel_ht.c
  47 @@ -294,6 +294,15 @@ minstrel_get_ratestats(struct minstrel_h
  48         return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES];
  49  }
  50
  51 +static unsigned int
  52 +minstrel_ht_avg_ampdu_len(struct minstrel_ht_sta *mi)
  53 +{
  54 +       if (!mi->avg_ampdu_len)
  55 +               return AVG_AMPDU_SIZE;
  56 +
  57 +       return MINSTREL_TRUNC(mi->avg_ampdu_len);
  58 +}
  59 +
  60  /*
  61   * Return current throughput based on the average A-MPDU length, taking into
  62   * account the expected number of retransmissions and their expected length
  63 @@ -309,7 +318,7 @@ minstrel_ht_get_tp_avg(struct minstrel_h
  64                 return 0;
  65
  66         if (group != MINSTREL_CCK_GROUP)
  67 -               nsecs = 1000 * mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len);
  68 +               nsecs = 1000 * mi->overhead / minstrel_ht_avg_ampdu_len(mi);
  69
  70         nsecs += minstrel_mcs_groups[group].duration[rate] <<
  71                  minstrel_mcs_groups[group].shift;
  72 @@ -503,8 +512,12 @@ minstrel_ht_update_stats(struct minstrel
  73         u16 tmp_cck_tp_rate[MAX_THR_RATES], index;
  74
  75         if (mi->ampdu_packets > 0) {
  76 -               mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
  77 -                       MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL);
  78 +               if (!ieee80211_hw_check(mp->hw, TX_STATUS_NO_AMPDU_LEN))
  79 +                       mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
  80 +                               MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets),
  81 +                                             EWMA_LEVEL);
  82 +               else
  83 +                       mi->avg_ampdu_len = 0;
  84                 mi->ampdu_len = 0;
  85                 mi->ampdu_packets = 0;
  86         }
  87 @@ -709,7 +722,9 @@ minstrel_ht_tx_status(void *priv, struct
  88         mi->ampdu_len += info->status.ampdu_len;
  89
  90         if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) {
  91 -               mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len);
  92 +               int avg_ampdu_len = minstrel_ht_avg_ampdu_len(mi);
  93 +
  94 +               mi->sample_wait = 16 + 2 * avg_ampdu_len;
  95                 mi->sample_tries = 1;
  96                 mi->sample_count--;
  97         }
  98 @@ -777,7 +792,7 @@ minstrel_calc_retransmit(struct minstrel
  99         unsigned int cw = mp->cw_min;
 100         unsigned int ctime = 0;
 101         unsigned int t_slot = 9; /* FIXME */
 102 -       unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len);
 103 +       unsigned int ampdu_len = minstrel_ht_avg_ampdu_len(mi);
 104         unsigned int overhead = 0, overhead_rtscts = 0;
 105
 106         mrs = minstrel_get_ratestats(mi, index);
 107 --- a/net/mac80211/rc80211_minstrel_ht_debugfs.c
 108 +++ b/net/mac80211/rc80211_minstrel_ht_debugfs.c
 109 @@ -163,9 +163,10 @@ minstrel_ht_stats_open(struct inode *ino
 110                         "lookaround %d\n",
 111                         max(0, (int) mi->total_packets - (int) mi->sample_packets),
 112                         mi->sample_packets);
 113 -       p += sprintf(p, "Average # of aggregated frames per A-MPDU: %d.%d\n",
 114 -               MINSTREL_TRUNC(mi->avg_ampdu_len),
 115 -               MINSTREL_TRUNC(mi->avg_ampdu_len * 10) % 10);
 116 +       if (mi->avg_ampdu_len)
 117 +               p += sprintf(p, "Average # of aggregated frames per A-MPDU: %d.%d\n",
 118 +                       MINSTREL_TRUNC(mi->avg_ampdu_len),
 119 +                       MINSTREL_TRUNC(mi->avg_ampdu_len * 10) % 10);
 120         ms->len = p - ms->buf;
 121         WARN_ON(ms->len + sizeof(*ms) > 32768);
 122