net: wrap sk->sk_backlog_rcv()

Wrap calling sk->sk_backlog_rcv() in a function. This will allow extending the
generic sk_backlog_rcv behaviour.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/sock.h

@@ -482,6 +482,11 @@ static inline void sk_add_backlog(struct sock *sk, struct sk_buff *skb)
 	skb->next = NULL;
 }
 
+static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
+{
+	return sk->sk_backlog_rcv(sk, skb);
+}
+
 #define sk_wait_event(__sk, __timeo, __condition)			\
 	({	int __rc;						\
 		release_sock(__sk);					\

include/net/tcp.h

@@ -896,7 +896,7 @@ static inline int tcp_prequeue(struct sock *sk, struct sk_buff *skb)
 			BUG_ON(sock_owned_by_user(sk));
 
 			while ((skb1 = __skb_dequeue(&tp->ucopy.prequeue)) != NULL) {
-				sk->sk_backlog_rcv(sk, skb1);
+				sk_backlog_rcv(sk, skb1);
 				NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPPREQUEUEDROPPED);
 			}
 

net/core/sock.c

@@ -327,7 +327,7 @@ int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
 		 */
 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
 
-		rc = sk->sk_backlog_rcv(sk, skb);
+		rc = sk_backlog_rcv(sk, skb);
 
 		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
 	} else
@@ -1374,7 +1374,7 @@ static void __release_sock(struct sock *sk)
 			struct sk_buff *next = skb->next;
 
 			skb->next = NULL;
-			sk->sk_backlog_rcv(sk, skb);
+			sk_backlog_rcv(sk, skb);
 
 			/*
 			 * We are in process context here with softirqs

net/ipv4/tcp.c

@@ -1161,7 +1161,7 @@ static void tcp_prequeue_process(struct sock *sk)
 	 * necessary */
 	local_bh_disable();
 	while ((skb = __skb_dequeue(&tp->ucopy.prequeue)) != NULL)
-		sk->sk_backlog_rcv(sk, skb);
+		sk_backlog_rcv(sk, skb);
 	local_bh_enable();
 
 	/* Clear memory counter. */

net/ipv4/tcp_timer.c

@@ -201,7 +201,7 @@ static void tcp_delack_timer(unsigned long data)
 		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPSCHEDULERFAILED);
 
 		while ((skb = __skb_dequeue(&tp->ucopy.prequeue)) != NULL)
-			sk->sk_backlog_rcv(sk, skb);
+			sk_backlog_rcv(sk, skb);
 
 		tp->ucopy.memory = 0;
 	}