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    SubjectRe: [PATCH RFC] virtio_net: fix refill related races
    Hello, Michael.

    On Tue, Dec 20, 2011 at 09:09:08PM +0200, Michael S. Tsirkin wrote:
    > 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?

    No, it's not. Normal workqueues only guarantee non-reentrance on
    local CPU. If you want to guarantee that only one instance of a given
    item is executing across all CPUs, you need to use the nrt workqueue.

    Thanks.

    --
    tejun


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