commit fdd6681d92a70b3db73cdb61c6b4053f2f8003b3
author Amerigo Wang <amwang@redhat.com> Mon Sep 10 02:48:44 2012 +0000
committer David S. Miller <davem@davemloft.net> Mon Sep 10 16:31:18 2012 -0400
tree 15a050d4fd0ffd4082fefcd9d2ad454b0c06218f
parent 6d57e9078e880a3dd232d579f42ac437a8f1ef7b

ipv6: remove some useless RCU read lock

After this commit:
	commit 97cac0821af4474ec4ba3a9e7a36b98ed9b6db88
	Author: David S. Miller <davem@davemloft.net>
	Date:   Mon Jul 2 22:43:47 2012 -0700

	    ipv6: Store route neighbour in rt6_info struct.

we no longer use RCU to protect route neighbour.

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/ip6_output.c

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index a4f6263..3dd4a37 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -123,16 +123,11 @@
 				skb->len);
 	}
 
-	rcu_read_lock();
 	rt = (struct rt6_info *) dst;
 	neigh = rt->n;
-	if (neigh) {
-		int res = dst_neigh_output(dst, neigh, skb);
+	if (neigh)
+		return dst_neigh_output(dst, neigh, skb);
 
-		rcu_read_unlock();
-		return res;
-	}
-	rcu_read_unlock();
 	IP6_INC_STATS_BH(dev_net(dst->dev),
 			 ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
 	kfree_skb(skb);
@@ -983,7 +978,6 @@
 	 * dst entry and replace it instead with the
 	 * dst entry of the nexthop router
 	 */
-	rcu_read_lock();
 	rt = (struct rt6_info *) *dst;
 	n = rt->n;
 	if (n && !(n->nud_state & NUD_VALID)) {
@@ -991,7 +985,6 @@
 		struct flowi6 fl_gw6;
 		int redirect;
 
-		rcu_read_unlock();
 		ifp = ipv6_get_ifaddr(net, &fl6->saddr,
 				      (*dst)->dev, 1);
 
@@ -1011,8 +1004,6 @@
 			if ((err = (*dst)->error))
 				goto out_err_release;
 		}
-	} else {
-		rcu_read_unlock();
 	}
 #endif