Commit 71ba088c authored by Paolo Abeni's avatar Paolo Abeni Committed by David S. Miller
Browse files

mptcp: cleanup accept and poll 



After the previous patch,  msk->subflow will never be deleted during
the whole msk lifetime. We don't need anymore to acquire references to
it in mptcp_stream_accept() and we can use the listener subflow accept
queue to simplify mptcp_poll() for listener socket.

Overall this removes a lock pair and 4 more atomic operations per
accept().

Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent b29fcfb5

net/mptcp/protocol.c

+7 −18
Original line number Diff line number Diff line
@@ -3493,17 +3493,9 @@ static int mptcp_stream_accept(struct socket *sock, struct socket *newsock, 


	pr_debug("msk=%p", msk);



	lock_sock(sock->sk);

	if (sock->sk->sk_state != TCP_LISTEN)

		goto unlock_fail;



	ssock = __mptcp_nmpc_socket(msk);

	if (!ssock)

		goto unlock_fail;



	clear_bit(MPTCP_DATA_READY, &msk->flags);

	sock_hold(ssock->sk);

	release_sock(sock->sk);

		return -EINVAL;



	err = ssock->ops->accept(sock, newsock, flags, kern);

	if (err == 0 && !mptcp_is_tcpsk(newsock->sk)) {
@@ -3543,14 +3535,7 @@ static int mptcp_stream_accept(struct socket *sock, struct socket *newsock, 
		release_sock(newsk);

	}



	if (inet_csk_listen_poll(ssock->sk))

		set_bit(MPTCP_DATA_READY, &msk->flags);

	sock_put(ssock->sk);

	return err;



unlock_fail:

	release_sock(sock->sk);

	return -EINVAL;

}



static __poll_t mptcp_check_readable(struct mptcp_sock *msk)
@@ -3596,8 +3581,12 @@ static __poll_t mptcp_poll(struct file *file, struct socket *sock, 


	state = inet_sk_state_load(sk);

	pr_debug("msk=%p state=%d flags=%lx", msk, state, msk->flags);

	if (state == TCP_LISTEN)

		return test_bit(MPTCP_DATA_READY, &msk->flags) ? EPOLLIN | EPOLLRDNORM : 0;

	if (state == TCP_LISTEN) {

		if (WARN_ON_ONCE(!msk->subflow || !msk->subflow->sk))

			return 0;



		return inet_csk_listen_poll(msk->subflow->sk);

	}



	if (state != TCP_SYN_SENT && state != TCP_SYN_RECV) {

		mask |= mptcp_check_readable(msk);

net/mptcp/protocol.h

+0 −1
Original line number Diff line number Diff line
@@ -111,7 +111,6 @@ 
#define MPTCP_RST_TRANSIENT	BIT(0)



/* MPTCP socket flags */

#define MPTCP_DATA_READY	0

#define MPTCP_NOSPACE		1

#define MPTCP_WORK_RTX		2

#define MPTCP_WORK_EOF		3

net/mptcp/subflow.c

+0 −1
Original line number Diff line number Diff line
@@ -1293,7 +1293,6 @@ static void subflow_data_ready(struct sock *sk) 
		if (reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue))

			return;



		set_bit(MPTCP_DATA_READY, &msk->flags);

		parent->sk_data_ready(parent);

		return;

	}