dccp/tcp: Remove an unused argument in inet_csk_listen_start().

The commit 1295e2cf ("inet: minor optimization for backlog setting in
listen(2)") added change so that sk_max_ack_backlog is initialised earlier
in inet_dccp_listen() and inet_listen().  Since then, we no longer use
backlog in inet_csk_listen_start(), so let's remove it.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Richard Sailer <richard_siegfried@systemli.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

include/net/inet_connection_sock.h

@@ -304,7 +304,7 @@ static inline __poll_t inet_csk_listen_poll(const struct sock *sk)
 			(EPOLLIN | EPOLLRDNORM) : 0;
 }
 
-int inet_csk_listen_start(struct sock *sk, int backlog);
+int inet_csk_listen_start(struct sock *sk);
 void inet_csk_listen_stop(struct sock *sk);
 
 void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr);

net/dccp/proto.c

@@ -238,7 +238,7 @@ void dccp_destroy_sock(struct sock *sk)
 
 EXPORT_SYMBOL_GPL(dccp_destroy_sock);
 
-static inline int dccp_listen_start(struct sock *sk, int backlog)
+static inline int dccp_listen_start(struct sock *sk)
 {
 	struct dccp_sock *dp = dccp_sk(sk);
 
@@ -246,7 +246,7 @@ static inline int dccp_listen_start(struct sock *sk, int backlog)
 	/* do not start to listen if feature negotiation setup fails */
 	if (dccp_feat_finalise_settings(dp))
 		return -EPROTO;
-	return inet_csk_listen_start(sk, backlog);
+	return inet_csk_listen_start(sk);
 }
 
 static inline int dccp_need_reset(int state)
@@ -935,7 +935,7 @@ int inet_dccp_listen(struct socket *sock, int backlog)
 		 * FIXME: here it probably should be sk->sk_prot->listen_start
 		 * see tcp_listen_start
 		 */
-		err = dccp_listen_start(sk, backlog);
+		err = dccp_listen_start(sk);
 		if (err)
 			goto out;
 	}

net/ipv4/af_inet.c

@@ -225,7 +225,7 @@ int inet_listen(struct socket *sock, int backlog)
 			tcp_fastopen_init_key_once(sock_net(sk));
 		}
 
-		err = inet_csk_listen_start(sk, backlog);
+		err = inet_csk_listen_start(sk);
 		if (err)
 			goto out;
 		tcp_call_bpf(sk, BPF_SOCK_OPS_TCP_LISTEN_CB, 0, NULL);

net/ipv4/inet_connection_sock.c

@@ -1035,7 +1035,7 @@ void inet_csk_prepare_forced_close(struct sock *sk)
 }
 EXPORT_SYMBOL(inet_csk_prepare_forced_close);
 
-int inet_csk_listen_start(struct sock *sk, int backlog)
+int inet_csk_listen_start(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct inet_sock *inet = inet_sk(sk);

tools/testing/selftests/bpf/progs/test_sk_storage_tracing.c

@@ -68,7 +68,7 @@ static void set_task_info(struct sock *sk)
 }
 
 SEC("fentry/inet_csk_listen_start")
-int BPF_PROG(trace_inet_csk_listen_start, struct sock *sk, int backlog)
+int BPF_PROG(trace_inet_csk_listen_start, struct sock *sk)
 {
 	set_task_info(sk);