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
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4AEE71EC.7040208@gmail.com \
--to=eric.dumazet@gmail.com \
--cc=davem@davemloft.net \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).