epoll keyed wakeups: make sockets use keyed wakeups

Add support for event-aware wakeups to the sockets code.  Events are
delivered to the wakeup target, so that epoll can avoid spurious wakeups
for non-interesting events.

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: William Lee Irwin III <wli@movementarian.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/net/core/sock.c b/net/core/sock.c
index 0620046e4eba837d0ecdf72b5eb6dcc192060ed5..7dbf3ffb35ccd6cb3308dab70fa33ce9cd9f8d5c 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1677,7 +1677,7 @@ static void sock_def_error_report(struct sock *sk)
 {
        read_lock(&sk->sk_callback_lock);
        if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
-               wake_up_interruptible(sk->sk_sleep);
+               wake_up_interruptible_poll(sk->sk_sleep, POLLERR);
        sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
        read_unlock(&sk->sk_callback_lock);
 }
@@ -1686,7 +1686,8 @@ static void sock_def_readable(struct sock *sk, int len)
 {
        read_lock(&sk->sk_callback_lock);
        if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
-               wake_up_interruptible_sync(sk->sk_sleep);
+               wake_up_interruptible_sync_poll(sk->sk_sleep, POLLIN |
+                                               POLLRDNORM | POLLRDBAND);
        sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
        read_unlock(&sk->sk_callback_lock);
 }
@@ -1700,7 +1701,8 @@ static void sock_def_write_space(struct sock *sk)
         */
        if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
                if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
-                       wake_up_interruptible_sync(sk->sk_sleep);
+                       wake_up_interruptible_sync_poll(sk->sk_sleep, POLLOUT |
+                                               POLLWRNORM | POLLWRBAND);
 
                /* Should agree with poll, otherwise some programs break */
                if (sock_writeable(sk))