Commit e16aa207 authored by Ralf Baechle's avatar Ralf Baechle Committed by David S. Miller
Browse files

[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: default avatarRalf Baechle <ralf@linux-mips.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 26db1677

net/core/wireless.c

+2 −2
Original line number Diff line number Diff line
@@ -2130,7 +2130,7 @@ int iw_handler_set_spy(struct net_device * dev, 
	 * The rtnl_lock() make sure we don't race with the other iw_handlers.

	 * This make sure wireless_spy_update() "see" that the spy list

	 * is temporarily disabled. */

	wmb();

	smp_wmb();



	/* Are there are addresses to copy? */

	if(wrqu->data.length > 0) {
@@ -2159,7 +2159,7 @@ int iw_handler_set_spy(struct net_device * dev, 
	}



	/* Make sure above is updated before re-enabling */

	wmb();

	smp_wmb();



	/* Enable addresses */

	spydata->spy_number = wrqu->data.length;

net/ipv4/inet_timewait_sock.c

+1 −1
Original line number Diff line number Diff line
@@ -178,7 +178,7 @@ void inet_twdr_hangman(unsigned long data) 
	need_timer = 0;

	if (inet_twdr_do_twkill_work(twdr, twdr->slot)) {

		twdr->thread_slots |= (1 << twdr->slot);

		mb();

		smp_mb();

		schedule_work(&twdr->twkill_work);

		need_timer = 1;

	} else {

net/ipv4/tcp_input.c

+2 −2
Original line number Diff line number Diff line
@@ -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);

net/packet/af_packet.c

+1 −1
Original line number Diff line number Diff line
@@ -660,7 +660,7 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packe 
	sll->sll_ifindex = dev->ifindex;



	h->tp_status = status;

	mb();

	smp_mb();



	{

		struct page *p_start, *p_end;

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