[NETLINK]: Un-duplicate rcv wakeup logic.

net/netlink/af_netlink.c

@@ -585,6 +585,16 @@ void netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code)
 	read_unlock(&nl_table_lock);
 }
 
+static inline void netlink_rcv_wake(struct sock *sk)
+{
+	struct netlink_opt *nlk = nlk_sk(sk);
+
+	if (skb_queue_len(&sk->receive_queue) == 0)
+		clear_bit(0, &nlk->state);
+	if (!test_bit(0, &nlk->state))
+		wake_up_interruptible(&nlk->wait);
+}
+
 static int netlink_sendmsg(struct kiocb *iocb, struct socket *sock,
 			   struct msghdr *msg, int len,
 			   struct scm_cookie *scm)
@@ -706,10 +716,7 @@ static int netlink_recvmsg(struct kiocb *iocb, struct socket *sock,
 		netlink_dump(sk);
 
 out:
-	if (skb_queue_len(&sk->receive_queue) == 0)
-		clear_bit(0, &nlk->state);
-	if (!test_bit(0, &nlk->state))
-		wake_up_interruptible(&nlk->wait);
+	netlink_rcv_wake(sk);
 	return err ? : copied;
 }
 
@@ -719,11 +726,7 @@ void netlink_data_ready(struct sock *sk, int len)
 
 	if (nlk->data_ready)
 		nlk->data_ready(sk, len);
-
-	if (skb_queue_len(&sk->receive_queue) == 0)
-		clear_bit(0, &nlk->state);
-	if (!test_bit(0, &nlk->state))
-		wake_up_interruptible(&nlk->wait);
+	netlink_rcv_wake(sk);
 }
 
 /*