From: Geliang Tang <tanggeliang@kylinos.cn>

Factor out a new helper tcp_recv_should_stop() from tcp_recvmsg_locked()
and tcp_splice_read() to check whether to stop receiving. And use this
helper in mptcp_recvmsg() and mptcp_splice_read() to reduce redundant code.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 include/net/tcp.h    |  9 +++++++++
 net/ipv4/tcp.c       | 10 ++--------
 net/mptcp/protocol.c | 10 ++--------
 3 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/include/net/tcp.h b/include/net/tcp.h
index cecec1a92d5e..a64b6159f93c 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -2951,4 +2951,13 @@ enum skb_drop_reason tcp_inbound_hash(struct sock *sk,
 		const void *saddr, const void *daddr,
 		int family, int dif, int sdif);
 
+static inline int tcp_recv_should_stop(struct sock *sk, long timeo)
+{
+	return sk->sk_err ||
+	       sk->sk_state == TCP_CLOSE ||
+	       (sk->sk_shutdown & RCV_SHUTDOWN) ||
+	       signal_pending(current) ||
+	       !timeo;
+}
+
 #endif	/* _TCP_H */
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index ae0000215ff4..e6e07df3979f 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -894,9 +894,7 @@ ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos,
 		release_sock(sk);
 		lock_sock(sk);
 
-		if (sk->sk_err || sk->sk_state == TCP_CLOSE ||
-		    (sk->sk_shutdown & RCV_SHUTDOWN) ||
-		    signal_pending(current))
+		if (tcp_recv_should_stop(sk, timeo))
 			break;
 	}
 
@@ -2783,11 +2781,7 @@ static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len,
 			break;
 
 		if (copied) {
-			if (!timeo ||
-			    sk->sk_err ||
-			    sk->sk_state == TCP_CLOSE ||
-			    (sk->sk_shutdown & RCV_SHUTDOWN) ||
-			    signal_pending(current))
+			if (tcp_recv_should_stop(sk, timeo))
 				break;
 		} else {
 			if (sock_flag(sk, SOCK_DONE))
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index fd9a574d1dda..9b0b6324fb56 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -2316,11 +2316,7 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 			break;
 
 		if (copied) {
-			if (sk->sk_err ||
-			    sk->sk_state == TCP_CLOSE ||
-			    (sk->sk_shutdown & RCV_SHUTDOWN) ||
-			    !timeo ||
-			    signal_pending(current))
+			if (tcp_recv_should_stop(sk, timeo))
 				break;
 		} else {
 			if (sk->sk_err) {
@@ -4506,9 +4502,7 @@ static ssize_t mptcp_splice_read(struct socket *sock, loff_t *ppos,
 		release_sock(sk);
 		lock_sock(sk);
 
-		if (sk->sk_err || sk->sk_state == TCP_CLOSE ||
-		    (sk->sk_shutdown & RCV_SHUTDOWN) ||
-		    signal_pending(current))
+		if (tcp_recv_should_stop(sk, timeo))
 			break;
 	}
 
-- 
2.52.0