Commit 2fe11c9d authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jakub Kicinski
Browse files

net/tcp: optimise locking for blocking splice 



Even when tcp_splice_read() reads all it was asked for, for blocking
sockets it'll release and immediately regrab the socket lock, loop
around and break on the while check.

Check tss.len right after we adjust it, and return if we're done.
That saves us one release_sock(); lock_sock(); pair per successful
blocking splice read.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/80736a2cc6d478c383ea565ba825eaf4d1abd876.1687523671.git.asml.silence@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 3f5f118b

net/ipv4/tcp.c

+1 −1
Original line number Diff line number Diff line
@@ -839,7 +839,7 @@ ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos, 
		tss.len -= ret;

		spliced += ret;



		if (!timeo)

		if (!tss.len || !timeo)

			break;

		release_sock(sk);

		lock_sock(sk);