netdev - [PATCH net-next 2/3] tun: avoid extra timer schedule in tun_flow

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Date:   Fri, 20 Oct 2017 11:29:56 -0700
From:   Eric Dumazet <edumazet@...gle.com>
To:     "David S . Miller" <davem@...emloft.net>
Cc:     netdev <netdev@...r.kernel.org>,
        Eric Dumazet <edumazet@...gle.com>,
        Eric Dumazet <eric.dumazet@...il.com>,
        Jason Wang <jasowang@...hat.com>
Subject: [PATCH net-next 2/3] tun: avoid extra timer schedule in tun_flow_cleanup()

If tun_flow_cleanup() deleted all flows, no need to
arm the timer again. It will be armed next time
tun_flow_update() is called.

Signed-off-by: Eric Dumazet <edumazet@...gle.com>
---
 drivers/net/tun.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index f9541f7f9fb7592b50ac818702006f4f1042b448..995887de5a98283382a631bcb8dfd874a4037ed3 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -461,11 +461,14 @@ static void tun_flow_cleanup(unsigned long data)
 
 		hlist_for_each_entry_safe(e, n, &tun->flows[i], hash_link) {
 			unsigned long this_timer;
-			count++;
+
 			this_timer = e->updated + delay;
-			if (time_before_eq(this_timer, jiffies))
+			if (time_before_eq(this_timer, jiffies)) {
 				tun_flow_delete(tun, e);
-			else if (time_before(this_timer, next_timer))
+				continue;
+			}
+			count++;
+			if (time_before(this_timer, next_timer))
 				next_timer = this_timer;
 		}
 	}
-- 
2.15.0.rc0.271.g36b669edcc-goog