[NET]: Memory barrier cleanups

I believe all the below memory barriers only matter on SMP so
therefore the smp_* variant of the barrier should be used.

I'm wondering if the barrier in net/ipv4/inet_timewait_sock.c should be
dropped entirely.  schedule_work's implementation currently implies a
memory barrier and I think sane semantics of schedule_work() should imply
a memory barrier, as needed so the caller shouldn't have to worry.
It's not quite obvious why the barrier in net/packet/af_packet.c is
needed; maybe it should be implied through flush_dcache_page?

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 9304034c0c47..c701f6abbfc1 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4235,7 +4235,7 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
                  * Change state from SYN-SENT only after copied_seq
                  * is initialized. */
                 tp->copied_seq = tp->rcv_nxt;
-                mb();
+                smp_mb();
                 tcp_set_state(sk, TCP_ESTABLISHED);
 
                 security_inet_conn_established(sk, skb);
@@ -4483,7 +4483,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
                 case TCP_SYN_RECV:
                         if (acceptable) {
                                 tp->copied_seq = tp->rcv_nxt;
-                                mb();
+                                smp_mb();
                                 tcp_set_state(sk, TCP_ESTABLISHED);
                                 sk->sk_state_change(sk);