[PATCH 37/37] net: Make softirq vector masking finegrained on release_sock()

[Frederic Weisbecker]

This is a usage example of spin_lock_bh_mask(). NET_RX, TIMER and
TASKLET are the three softirqs that have been reported by lockdep to
be used for this socket lock, at least on my own usecases.

Reviewed-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Cc: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Cc: Joel Fernandes <joel@xxxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Pavan Kondeti <pkondeti@xxxxxxxxxxxxxx>
Cc: Paul E . McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: David S . Miller <davem@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
---
 net/core/sock.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/core/sock.c b/net/core/sock.c
index 6aa2e7e0b4fb..d6c7dca82ad9 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2795,7 +2795,11 @@ EXPORT_SYMBOL(lock_sock_nested);
 
 void release_sock(struct sock *sk)
 {
-	spin_lock_bh(&sk->sk_lock.slock);
+	unsigned int bh;
+
+	bh = spin_lock_bh_mask(&sk->sk_lock.slock,
+			       BIT(NET_RX_SOFTIRQ) | BIT(TIMER_SOFTIRQ) |
+			       BIT(HRTIMER_SOFTIRQ) | BIT(TASKLET_SOFTIRQ));
 	if (sk->sk_backlog.tail)
 		__release_sock(sk);
 
@@ -2808,7 +2812,7 @@ void release_sock(struct sock *sk)
 	sock_release_ownership(sk);
 	if (waitqueue_active(&sk->sk_lock.wq))
 		wake_up(&sk->sk_lock.wq);
-	spin_unlock_bh(&sk->sk_lock.slock);
+	spin_unlock_bh_mask(&sk->sk_lock.slock, bh);
 }
 EXPORT_SYMBOL(release_sock);
 
-- 
2.21.0