openwrt/package/kernel/mac80211/patches/subsys/336-mac80211-only-accumulate-airtime-deficit-for-active-.patch
Felix Fietkau 6d49a25804 mac80211: add airtime fairness improvements
This reverts the airtime scheduler back from the virtual-time based scheduler
to the deficit round robin scheduler implementation.
This reduces burstiness and improves fairness by improving interaction with AQL.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2022-06-25 23:28:09 +02:00

37 lines
1.2 KiB
Diff

From: Felix Fietkau <nbd@nbd.name>
Date: Sat, 25 Jun 2022 23:10:19 +0200
Subject: [PATCH] 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: Felix Fietkau <nbd@nbd.name>
---
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -1900,6 +1900,7 @@ void ieee80211_sta_register_airtime(stru
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;
@@ -1909,7 +1910,11 @@ void ieee80211_sta_register_airtime(stru
spin_lock_bh(&local->active_txq_lock[ac]);
sta->airtime[ac].tx_airtime += tx_airtime;
sta->airtime[ac].rx_airtime += rx_airtime;
- sta->airtime[ac].deficit -= 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);