Commit 93afcfd1 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

tcp: small optimization in tcp recvmsg() 



When reading large chunks of data, incoming packets might
be added to the backlog from BH.

tcp recvmsg() detects the backlog queue is not empty, and uses
a release_sock()/lock_sock() pair to process this backlog.

We now have __sk_flush_backlog() to perform this
a bit faster.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 91b6d325

net/ipv4/tcp.c

+1 −2
Original line number Diff line number Diff line
@@ -2409,8 +2409,7 @@ static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len, 


		if (copied >= target) {

			/* Do not sleep, just process backlog. */

			release_sock(sk);

			lock_sock(sk);

			__sk_flush_backlog(sk);

		} else {

			sk_wait_data(sk, &timeo, last);

		}