From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH net-next-2.6] ipv4: RCU changes in __mkroute_input() Date: Thu, 03 Jun 2010 16:13:21 +0200 Message-ID: <1275574401.2456.55.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev To: David Miller Return-path: Received: from mail-wy0-f174.google.com ([74.125.82.174]:64472 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755123Ab0FCOUA (ORCPT ); Thu, 3 Jun 2010 10:20:00 -0400 Received: by wyi11 with SMTP id 11so86974wyi.19 for ; Thu, 03 Jun 2010 07:19:59 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: Avoid two atomic ops on output device refcount Signed-off-by: Eric Dumazet --- net/ipv4/route.c | 8 +++----- 1 files changed, 3 insertions(+), 5 deletions(-) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 1cfe0d1..7b8eacd 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1957,22 +1957,22 @@ static void ip_handle_martian_source(struct net_device *dev, #endif } +/* called in rcu_read_lock() section */ static int __mkroute_input(struct sk_buff *skb, struct fib_result *res, struct in_device *in_dev, __be32 daddr, __be32 saddr, u32 tos, struct rtable **result) { - struct rtable *rth; int err; struct in_device *out_dev; - unsigned flags = 0; + unsigned int flags = 0; __be32 spec_dst; u32 itag; /* get a working reference to the output device */ - out_dev = in_dev_get(FIB_RES_DEV(*res)); + out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res)); if (out_dev == NULL) { if (net_ratelimit()) printk(KERN_CRIT "Bug in ip_route_input" \ @@ -2053,8 +2053,6 @@ static int __mkroute_input(struct sk_buff *skb, *result = rth; err = 0; cleanup: - /* release the working reference to the output device */ - in_dev_put(out_dev); return err; }