net: Make ip_ra_chain per struct net

This is optimization, which makes ip_call_ra_chain()
iterate less sockets to find the sockets it's looking for.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 57fc13c..7582713 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -159,7 +159,7 @@ bool ip_call_ra_chain(struct sk_buff *skb)
 	struct net_device *dev = skb->dev;
 	struct net *net = dev_net(dev);
 
-	for (ra = rcu_dereference(ip_ra_chain); ra; ra = rcu_dereference(ra->next)) {
+	for (ra = rcu_dereference(net->ipv4.ra_chain); ra; ra = rcu_dereference(ra->next)) {
 		struct sock *sk = ra->sk;
 
 		/* If socket is bound to an interface, only report
@@ -167,8 +167,7 @@ bool ip_call_ra_chain(struct sk_buff *skb)
 		 */
 		if (sk && inet_sk(sk)->inet_num == protocol &&
 		    (!sk->sk_bound_dev_if ||
-		     sk->sk_bound_dev_if == dev->ifindex) &&
-		    net_eq(sock_net(sk), net)) {
+		     sk->sk_bound_dev_if == dev->ifindex)) {
 			if (ip_is_fragment(ip_hdr(skb))) {
 				if (ip_defrag(net, skb, IP_DEFRAG_CALL_RA_CHAIN))
 					return true;