From: Eric Dumazet <eric.dumazet@gmail.com>
To: "David S. Miller" <davem@davemloft.net>,
Linux Netdev List <netdev@vger.kernel.org>
Subject: [PATCH net-next-2.6] ifb: RCU locking avoids touching dev refcount
Date: Mon, 02 Nov 2009 06:45:16 +0100 [thread overview]
Message-ID: <4AEE71EC.7040208@gmail.com> (raw)
Avoids touching dev refcount in hotpath
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
---
drivers/net/ifb.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ifb.c b/drivers/net/ifb.c
index 030913f..69c2566 100644
--- a/drivers/net/ifb.c
+++ b/drivers/net/ifb.c
@@ -98,13 +98,15 @@ static void ri_tasklet(unsigned long dev)
stats->tx_packets++;
stats->tx_bytes +=skb->len;
- skb->dev = dev_get_by_index(&init_net, skb->iif);
+ rcu_read_lock();
+ skb->dev = dev_get_by_index_rcu(&init_net, skb->iif);
if (!skb->dev) {
+ rcu_read_unlock();
dev_kfree_skb(skb);
stats->tx_dropped++;
break;
}
- dev_put(skb->dev);
+ rcu_read_unlock();
skb->iif = _dev->ifindex;
if (from & AT_EGRESS) {
next reply other threads:[~2009-11-02 5:45 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-11-02 5:45 Eric Dumazet [this message]
2009-11-02 7:57 ` [PATCH net-next-2.6] ifb: RCU locking avoids touching dev refcount David Miller
2009-11-02 21:14 ` Jarek Poplawski
2009-11-02 21:34 ` Eric Dumazet
2009-11-02 21:40 ` Jarek Poplawski
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