Commit c77bfab9 authored by Felix Fietkau's avatar Felix Fietkau Committed by Johannes Berg
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wifi: mac80211: only accumulate airtime deficit for active clients 



When a client does not generate any local tx activity, accumulating airtime
deficit for the round-robin scheduler can be harmful. If this goes on for too
long, the deficit could grow quite large, which might cause unreasonable
initial latency once the client becomes active

Signed-off-by: default avatarFelix Fietkau <nbd@nbd.name>
Acked-by: default avatarToke Høiland-Jørgensen <toke@toke.dk>
Link: https://lore.kernel.org/r/20220625212411.36675-7-nbd@nbd.name


Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 3db2c560

net/mac80211/sta_info.c

+6 −1
Original line number Diff line number Diff line
@@ -2046,6 +2046,7 @@ void ieee80211_sta_register_airtime(struct ieee80211_sta *pubsta, u8 tid, 
	struct ieee80211_local *local = sta->sdata->local;

	u8 ac = ieee80211_ac_from_tid(tid);

	u32 airtime = 0;

	u32 diff;



	if (sta->local->airtime_flags & AIRTIME_USE_TX)

		airtime += tx_airtime;
@@ -2055,7 +2056,11 @@ void ieee80211_sta_register_airtime(struct ieee80211_sta *pubsta, u8 tid, 
	spin_lock_bh(&local->active_txq_lock[ac]);

	sta->airtime[ac].tx_airtime += tx_airtime;

	sta->airtime[ac].rx_airtime += rx_airtime;



	diff = (u32)jiffies - sta->airtime[ac].last_active;

	if (diff <= AIRTIME_ACTIVE_DURATION)

		sta->airtime[ac].deficit -= airtime;



	spin_unlock_bh(&local->active_txq_lock[ac]);

}

EXPORT_SYMBOL(ieee80211_sta_register_airtime);