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    SubjectRe: [PATCH v3 8/9] KVM-GST: adjust scheduler cpu power
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    On Wed, 2011-06-29 at 11:29 -0400, Glauber Costa wrote:
    > +#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
    > + if (static_branch((&paravirt_steal_rq_enabled))) {
    > + int is_idle;
    > + u64 st;
    > +
    > + is_idle = ((rq->curr != rq->idle) ||
    > + irq_count() != HARDIRQ_OFFSET);

    Now that hurt my brain. If the vcpu is idle, why does it want to run?
    How can an idle vcpu ever rack up steal time?

    Also, what's that HARDIRQ_OFFSET bit about? sorely lacking in
    explanation, and the Changelog to this patch is about as bad as the last
    one.

    > + __touch_steal_time(is_idle, delta, &st);
    > +
    > + steal = st * TICK_NSEC;
    > +
    > + delta -= steal;
    > + }
    > +#endif


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