[NET]: Prefetch dev->qdisc_lock in dev_queue_xmit()

We know the lock is going to be taken.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/dev.c b/net/core/dev.c
index 37c8810..9066c87 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1259,6 +1259,8 @@ int dev_queue_xmit(struct sk_buff *skb)
                if (skb_checksum_help(skb, 0))
                        goto out_kfree_skb;
 
+       spin_lock_prefetch(&dev->queue_lock);
+
        /* Disable soft irqs for various locks below. Also 
         * stops preemption for RCU. 
         */