[PATCH] mac80211: only schedule TXQ when reasonable airtime reporting

Ryder Lee
2021-02-05T12:56:30Z

For some drivers and hardware may report faulty airtime, which ends up
with excessive hold time (~0.9s on mt7915 multiclent tests) impacting
system performance.

Although issue has been fixed in driver, but it make sense to select txqi
depends on a reasonable airtime reporting to prevent such a case from
happening again.

Tested-by: Jiao Bo <jiao.bao@mediatek.com>
Tested-by: Sujuan Chen <sujuan.chen@mediatek.com>
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
---
net/mac80211/tx.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 6422da6690f7..0b8a8c3600f4 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -3770,6 +3770,10 @@ struct ieee80211_txq *ieee80211_next_txq(struct ieee80211_hw *hw, u8 ac)
sta->airtime_weight;

if (deficit < 0 || !aql_check) {
+ if (txqi->schedule_round == local->schedule_round[ac])
+ goto out;
+
+ txqi->schedule_round = local->schedule_round[ac];
list_move_tail(&txqi->schedule_order,
&local->active_txqs[txqi->txq.ac]);
goto begin;
--
2.18.0