Commit 1e061ab2 authored Jun 18, 2005 by Herbert Xu Committed by David S. Miller Jun 18, 2005

[SCTP]: Replace spin_lock_irqsave with spin_lock_bh



This patch replaces the spin_lock_irqsave call on the receive queue
lock in SCTP with spin_lock_bh.  Despite the proliferation of
spin_lock_irqsave calls in this stack, it is only entered from the
IPv4/IPv6 stack and user space.  That is, it is never entered from
hardirq context.

The call in question is only called from recvmsg which means that
IRQs aren't disabled.  Therefore it is safe to replace it with
spin_lock_bh.
 
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent e0f9f858

net/sctp/socket.c

+2 −6

Original line number	Diff line number	Diff line
		@@ -4368,15 +4368,11 @@ static struct sk_buff sctp_skb_recv_datagram(struct sock sk, int flags,
		* However, this function was corrent in any case. 8)
		*/
		if (flags & MSG_PEEK) {
		unsigned long cpu_flags;

		sctp_spin_lock_irqsave(&sk->sk_receive_queue.lock,
		cpu_flags);
		spin_lock_bh(&sk->sk_receive_queue.lock);
		skb = skb_peek(&sk->sk_receive_queue);
		if (skb)
		atomic_inc(&skb->users);
		sctp_spin_unlock_irqrestore(&sk->sk_receive_queue.lock,
		cpu_flags);
		spin_unlock_bh(&sk->sk_receive_queue.lock);
		} else {
		skb = skb_dequeue(&sk->sk_receive_queue);
		}

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