tcp: tcp_prequeue() can use keyed wakeups

We can avoid waking up tasks not interested in receive notifications,
using wake_up_interruptible_poll() instead of wake_up_interruptible()

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tcp.h b/include/net/tcp.h
index ac37228b700137d84d6c7b69d152214a3dde782a..87d210bb12a4762a31e714f48d958a29b0b3cd09 100644 (file)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -908,7 +908,8 @@ static inline int tcp_prequeue(struct sock *sk, struct sk_buff *skb)
 
                tp->ucopy.memory = 0;
        } else if (skb_queue_len(&tp->ucopy.prequeue) == 1) {
-               wake_up_interruptible(sk->sk_sleep);
+               wake_up_interruptible_poll(sk->sk_sleep,
+                                          POLLIN | POLLRDNORM | POLLRDBAND);
                if (!inet_csk_ack_scheduled(sk))
                        inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
                                                  (3 * TCP_RTO_MIN) / 4,