diff options
Diffstat (limited to 'package/kernel/mac80211/patches/subsys/313-mac80211-improve-AQL-aggregation-estimation-for-low-.patch')
| -rw-r--r-- | package/kernel/mac80211/patches/subsys/313-mac80211-improve-AQL-aggregation-estimation-for-low-.patch | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/package/kernel/mac80211/patches/subsys/313-mac80211-improve-AQL-aggregation-estimation-for-low-.patch b/package/kernel/mac80211/patches/subsys/313-mac80211-improve-AQL-aggregation-estimation-for-low-.patch new file mode 100644 index 0000000000..565d9bec43 --- /dev/null +++ b/package/kernel/mac80211/patches/subsys/313-mac80211-improve-AQL-aggregation-estimation-for-low-.patch @@ -0,0 +1,66 @@ +From: Felix Fietkau <nbd@nbd.name> +Date: Wed, 12 Aug 2020 17:07:10 +0200 +Subject: [PATCH] mac80211: improve AQL aggregation estimation for low data + rates + +Links with low data rates use much smaller aggregates and are much more +sensitive to latency added by bufferbloat. +Tune the assumed aggregation length based on the tx rate duration. + +Signed-off-by: Felix Fietkau <nbd@nbd.name> +--- + +--- a/net/mac80211/airtime.c ++++ b/net/mac80211/airtime.c +@@ -646,27 +646,40 @@ u32 ieee80211_calc_expected_tx_airtime(s + if (pubsta) { + struct sta_info *sta = container_of(pubsta, struct sta_info, + sta); ++ struct ieee80211_rx_status stat; + struct ieee80211_tx_rate *rate = &sta->tx_stats.last_rate; + struct rate_info *ri = &sta->tx_stats.last_rate_info; +- u32 airtime; ++ u32 duration, overhead; ++ u8 agg_shift; + +- if (!(rate->flags & (IEEE80211_TX_RC_VHT_MCS | +- IEEE80211_TX_RC_MCS))) +- ampdu = false; ++ ieee80211_fill_rx_status(&stat, hw, rate, ri, band, len); ++ ++ if (stat.encoding == RX_ENC_LEGACY || !ampdu) ++ return ieee80211_calc_rx_airtime(hw, &stat, len); + ++ duration = ieee80211_get_rate_duration(hw, &stat, &overhead); + /* + * Assume that HT/VHT transmission on any AC except VO will + * use aggregation. Since we don't have reliable reporting +- * of aggregation length, assume an average of 16. ++ * of aggregation length, assume an average size based on the ++ * tx rate. + * This will not be very accurate, but much better than simply +- * assuming un-aggregated tx. ++ * assuming un-aggregated tx in all cases. + */ +- airtime = ieee80211_calc_tx_airtime_rate(hw, rate, ri, band, +- ampdu ? len * 16 : len); +- if (ampdu) +- airtime /= 16; ++ if (duration > 400) /* <= VHT20 MCS2 1S */ ++ agg_shift = 1; ++ else if (duration > 250) /* <= VHT20 MCS3 1S or MCS1 2S */ ++ agg_shift = 2; ++ else if (duration > 150) /* <= VHT20 MCS5 1S or MCS3 2S */ ++ agg_shift = 3; ++ else ++ agg_shift = 4; + +- return airtime; ++ duration *= len; ++ duration /= AVG_PKT_SIZE; ++ duration /= 1024; ++ ++ return duration + (overhead >> agg_shift); + } + + if (!conf) |