[PATCH v3 14/14] wifi: ath9k: Remove redundant rcu_read_lock/unlock() in spin_lock

[pengdonglin]

From: pengdonglin <pengdonglin@xxxxxxxxxx>

Since commit a8bb74acd8efe ("rcu: Consolidate RCU-sched update-side function definitions")
there is no difference between rcu_read_lock(), rcu_read_lock_bh() and
rcu_read_lock_sched() in terms of RCU read section and the relevant grace
period. That means that spin_lock(), which implies rcu_read_lock_sched(),
also implies rcu_read_lock().

There is no need no explicitly start a RCU read section if one has already
been started implicitly by spin_lock().

Simplify the code and remove the inner rcu_read_lock() invocation.

Cc: "Toke" <toke@xxxxxxx>
Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: pengdonglin <pengdonglin@xxxxxxxxxx>
Signed-off-by: pengdonglin <dolinux.peng@xxxxxxxxx>
---
 drivers/net/wireless/ath/ath9k/xmit.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 0ac9212e42f7..4a0f465aa2fe 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -1993,7 +1993,6 @@ void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
 
 	ieee80211_txq_schedule_start(hw, txq->mac80211_qnum);
 	spin_lock_bh(&sc->chan_lock);
-	rcu_read_lock();
 
 	if (sc->cur_chan->stopped)
 		goto out;
@@ -2011,7 +2010,6 @@ void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
 	}
 
 out:
-	rcu_read_unlock();
 	spin_unlock_bh(&sc->chan_lock);
 	ieee80211_txq_schedule_end(hw, txq->mac80211_qnum);
 }
-- 
2.34.1