package/kernel/mac80211/patches/subsys/339-v6.0-mac80211-exclude-multicast-packets-from-AQL-pending-.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Date: Wed, 13 Jul 2022 07:32:26 +0200
   3 Subject: [PATCH] mac80211: exclude multicast packets from AQL pending airtime
   4
   5 In AP mode, multicast traffic is handled very differently from normal traffic,
   6 especially if at least one client is in powersave mode.
   7 This means that multicast packets can be buffered a lot longer than normal
   8 unicast packets, and can eat up the AQL budget very quickly because of the low
   9 data rate.
  10 Along with the recent change to maintain a global PHY AQL limit, this can lead
  11 to significant latency spikes for unicast traffic.
  12
  13 Since queueing multicast to hardware is currently not constrained by AQL limits
  14 anyway, let's just exclude it from the AQL pending airtime calculation entirely.
  15
  16 Fixes: 8e4bac067105 ("wifi: mac80211: add a per-PHY AQL limit to improve fairness")
  17 Signed-off-by: Felix Fietkau <nbd@nbd.name>
  18 ---
  19
  20 --- a/net/mac80211/tx.c
  21 +++ b/net/mac80211/tx.c
  22 @@ -3792,7 +3792,7 @@ begin:
  23  encap_out:
  24         IEEE80211_SKB_CB(skb)->control.vif = vif;
  25
  26 -       if (vif &&
  27 +       if (tx.sta &&
  28             wiphy_ext_feature_isset(local->hw.wiphy, NL80211_EXT_FEATURE_AQL)) {
  29                 bool ampdu = txq->ac != IEEE80211_AC_VO;
  30                 u32 airtime;