Commit 5eef0b8d authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: lockless implementation of SO_TXREHASH 



sk->sk_txrehash readers are already safe against
concurrent change of this field.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 28b24f90

net/core/sock.c

+10 −13
Original line number Diff line number Diff line
@@ -1181,6 +1181,16 @@ int sk_setsockopt(struct sock *sk, int level, int optname, 
			WRITE_ONCE(sk->sk_pacing_rate, ulval);

		return 0;

		}

	case SO_TXREHASH:

		if (val < -1 || val > 1)

			return -EINVAL;

		if ((u8)val == SOCK_TXREHASH_DEFAULT)

			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);

		/* Paired with READ_ONCE() in tcp_rtx_synack()

		 * and sk_getsockopt().

		 */

		WRITE_ONCE(sk->sk_txrehash, (u8)val);

		return 0;

	}



	sockopt_lock_sock(sk);
@@ -1528,19 +1538,6 @@ int sk_setsockopt(struct sock *sk, int level, int optname, 
		break;

	}



	case SO_TXREHASH:

		if (val < -1 || val > 1) {

			ret = -EINVAL;

			break;

		}

		if ((u8)val == SOCK_TXREHASH_DEFAULT)

			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);

		/* Paired with READ_ONCE() in tcp_rtx_synack()

		 * and sk_getsockopt().

		 */

		WRITE_ONCE(sk->sk_txrehash, (u8)val);

		break;



	default:

		ret = -ENOPROTOOPT;

		break;