On Tue, Dec 13, 2011 at 01:05:11PM +1030, Rusty Russell wrote:

On Mon, 12 Dec 2011 13:54:06 +0200, "Michael S. Tsirkin" [off-list ref] wrote:

quoted

On Mon, Dec 12, 2011 at 09:25:07AM +1030, Rusty Russell wrote:

quoted

Orthogonally, the refill-stop code is still buggy, as you noted.

Sorry I don't understand how it's still buggy.

Both places where we call:

	cancel_delayed_work_sync(&vi->refill);

Do not actually guarantee that vi->refill isn't running, because it
can requeue itself.  A 'bool no_more_refill' field seems like the
simplest fix for this, but I don't think it's sufficient.

Tejun, is this correct?  What's the correct way to synchronously stop a
delayed_work which can "schedule_delayed_work(&vi->refill, HZ/2);" on
itself?

Thanks,
Rusty.

Another question, wanted to make sure:
virtnet_poll does schedule_delayed_work(&vi->refill, 0);
separately refill work itself also does
schedule_delayed_work(&vi->refill, HZ/2);
If two such events happen twice, on different CPUs, we are still guaranteed
the work will only run once, right?