Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e16aa207 authored Dec 07, 2006 by Ralf Baechle Committed by David S. Miller Dec 07, 2006

[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>

parent 26db1677

net/core/wireless.c

+2 −2

Original line number	Original line	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.		* 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		* This make sure wireless_spy_update() "see" that the spy list
	* is temporarily disabled. */		* is temporarily disabled. */
	wmb();		smp_wmb();

	/* Are there are addresses to copy? */		/* Are there are addresses to copy? */
	if(wrqu->data.length > 0) {		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 */		/* Make sure above is updated before re-enabling */
	wmb();		smp_wmb();

	/* Enable addresses */		/* Enable addresses */
	spydata->spy_number = wrqu->data.length;		spydata->spy_number = wrqu->data.length;

net/ipv4/inet_timewait_sock.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -178,7 +178,7 @@ void inet_twdr_hangman(unsigned long data)
	need_timer = 0;		need_timer = 0;
	if (inet_twdr_do_twkill_work(twdr, twdr->slot)) {		if (inet_twdr_do_twkill_work(twdr, twdr->slot)) {
	twdr->thread_slots \|= (1 << twdr->slot);		twdr->thread_slots \|= (1 << twdr->slot);
	mb();		smp_mb();
	schedule_work(&twdr->twkill_work);		schedule_work(&twdr->twkill_work);
	need_timer = 1;		need_timer = 1;
	} else {		} else {

net/ipv4/tcp_input.c

+2 −2

Original line number	Original line	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		* Change state from SYN-SENT only after copied_seq
	* is initialized. */		* is initialized. */
	tp->copied_seq = tp->rcv_nxt;		tp->copied_seq = tp->rcv_nxt;
	mb();		smp_mb();
	tcp_set_state(sk, TCP_ESTABLISHED);		tcp_set_state(sk, TCP_ESTABLISHED);

	security_inet_conn_established(sk, skb);		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:		case TCP_SYN_RECV:
	if (acceptable) {		if (acceptable) {
	tp->copied_seq = tp->rcv_nxt;		tp->copied_seq = tp->rcv_nxt;
	mb();		smp_mb();
	tcp_set_state(sk, TCP_ESTABLISHED);		tcp_set_state(sk, TCP_ESTABLISHED);
	sk->sk_state_change(sk);		sk->sk_state_change(sk);

net/packet/af_packet.c

+1 −1

Original line number	Original line	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;		sll->sll_ifindex = dev->ifindex;

	h->tp_status = status;		h->tp_status = status;
	mb();		smp_mb();

	{		{
	struct page p_start, p_end;		struct page p_start, p_end;