static void __sock_set_rcvbuf(struct sock *sk, int val)
{
	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
	 * as a negative value.
	 */
	val = min_t(int, val, INT_MAX / 2);
	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;

	/* We double it on the way in to account for "struct sk_buff" etc.
	 * overhead.   Applications assume that the SO_RCVBUF setting they make
	 * will allow that much actual data to be received on that socket.
	 *
	 * Applications are unaware that "struct sk_buff" and other overheads
	 * allocate from the receive buffer during socket buffer allocation.
	 *
	 * And after considering the possible alternatives, returning the value
	 * we actually used in getsockopt is the most desirable behavior.
	 */
	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
}
static void __sock_set_rcvbuf(struct sock *sk, int val)
{
	 
	val = min_t(int, val, INT_MAX / 2);
	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;

	 
	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
}