net: socket: add __sys_listen() helper; remove in-kernel call to syscall
Using the net-internal helper __sys_listen() allows us to avoid the
internal calls to the sys_listen() syscall.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
diff --git a/net/socket.c b/net/socket.c
index 64bdfdf..67d9d70 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1496,7 +1496,7 @@ SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen)
* ready for listening.
*/
-SYSCALL_DEFINE2(listen, int, fd, int, backlog)
+int __sys_listen(int fd, int backlog)
{
struct socket *sock;
int err, fput_needed;
@@ -1517,6 +1517,11 @@ SYSCALL_DEFINE2(listen, int, fd, int, backlog)
return err;
}
+SYSCALL_DEFINE2(listen, int, fd, int, backlog)
+{
+ return __sys_listen(fd, backlog);
+}
+
/*
* For accept, we attempt to create a new socket, set up the link
* with the client, wake up the client, then return the new
@@ -2487,7 +2492,7 @@ SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
err = __sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
break;
case SYS_LISTEN:
- err = sys_listen(a0, a1);
+ err = __sys_listen(a0, a1);
break;
case SYS_ACCEPT:
err = __sys_accept4(a0, (struct sockaddr __user *)a1,
