net: sk_sleep() helper

Define a new function to return the waitqueue of a "struct sock".

static inline wait_queue_head_t *sk_sleep(struct sock *sk)
{
	return sk->sk_sleep;
}

Change all read occurrences of sk_sleep by a call to this function.

Needed for a future RCU conversion. sk_sleep wont be a field directly
available.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bluetooth/bnep/netdev.c b/net/bluetooth/bnep/netdev.c
index d48b33f..0faad5c 100644
--- a/net/bluetooth/bnep/netdev.c
+++ b/net/bluetooth/bnep/netdev.c
@@ -109,7 +109,7 @@
 	}
 
 	skb_queue_tail(&sk->sk_write_queue, skb);
-	wake_up_interruptible(sk->sk_sleep);
+	wake_up_interruptible(sk_sleep(sk));
 #endif
 }
 
@@ -193,11 +193,11 @@
 	/*
 	 * We cannot send L2CAP packets from here as we are potentially in a bh.
 	 * So we have to queue them and wake up session thread which is sleeping
-	 * on the sk->sk_sleep.
+	 * on the sk_sleep(sk).
 	 */
 	dev->trans_start = jiffies;
 	skb_queue_tail(&sk->sk_write_queue, skb);
-	wake_up_interruptible(sk->sk_sleep);
+	wake_up_interruptible(sk_sleep(sk));
 
 	if (skb_queue_len(&sk->sk_write_queue) >= BNEP_TX_QUEUE_LEN) {
 		BT_DBG("tx queue is full");