From: Gao feng <gaofeng@cn.fujitsu.com>
Date: Wed, 19 Oct 2011 15:34:09 +0000 (+0000)
Subject: ipv4: avoid useless call of the function check_peer_pmtu
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=59445b6b1f90b97c4e28062b96306bacfa4fb170;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git

ipv4: avoid useless call of the function check_peer_pmtu

In func ipv4_dst_check,check_peer_pmtu should be called only when peer is updated.
So,if the peer is not updated in ip_rt_frag_needed,we can not inc __rt_peer_genid.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 1082460daca7..155138d8ec8b 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1593,11 +1593,10 @@ unsigned short ip_rt_frag_needed(struct net *net, const struct iphdr *iph,
 			est_mtu = mtu;
 			peer->pmtu_learned = mtu;
 			peer->pmtu_expires = pmtu_expires;
+			atomic_inc(&__rt_peer_genid);
 		}
 
 		inet_putpeer(peer);
-
-		atomic_inc(&__rt_peer_genid);
 	}
 	return est_mtu ? : new_mtu;
 }