From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] Fix locking in flush_backlog
Date: Tue, 23 Mar 2010 17:14:04 +0100
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To: Tom Herbert <therbert@google.com>
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Le mardi 23 mars 2010 =C3=A0 08:56 -0700, Tom Herbert a =C3=A9crit :

> Eric,
>=20
> I'm not sure what you're asking.  Do you just want to add spinlocks i=
n
> the flush_backlog function without changing the mechanism to call the
> function on each CPU, or keep flush_backlog but call it from
> netdev_run_todo for each queue?
>=20

keep flush_backlog() so that its role is obvious and indentation level
not too big.

static void flush_backlog(int cpu)
{
	struct softnet_data *queue =3D &per_cpu(softnet_data, cpu);
	struct sk_buff *skb, *tmp;
	unsigned long flags;

	spin_lock_irqsave(&queue->input_pkt_queue.lock, flags);
	skb_queue_walk_safe(&queue->input_pkt_queue, skb, tmp)
		if (skb->dev =3D=3D dev) {
			__skb_unlink(skb, &queue->input_pkt_queue);
			kfree_skb(skb);
		}
	spin_unlock_irqrestore(&queue->input_pkt_queue.lock, flags);
}

And call it from netdev_run_todo() :

for_each_online_cpu(i)
	flush_backlog(i);

This adds two lines to netdev_run_todo() only.

Thanks