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>

1 files changed, 2 insertions, 11 deletions

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index a4f6263fddca..3dd4a37488d5 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -123,16 +123,11 @@ static int ip6_finish_output2(struct sk_buff *skb)
                                 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 @@ static int ip6_dst_lookup_tail(struct sock *sk,
          * 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 @@ static int ip6_dst_lookup_tail(struct sock *sk,
                 struct flowi6 fl_gw6;
                 int redirect;
 
-                rcu_read_unlock();
                 ifp = ipv6_get_ifaddr(net, &fl6->saddr,
                                       (*dst)->dev, 1);
 
@@ -1011,8 +1004,6 @@ static int ip6_dst_lookup_tail(struct sock *sk,
                         if ((err = (*dst)->error))
                                 goto out_err_release;
                 }
-        } else {
-                rcu_read_unlock();
         }
 #endif