Messages in this thread | | | Date | Thu, 17 Jun 2010 09:02:29 -0700 | From | Arjan van de Ven <> | Subject | Re: [PATCH 09/12] irq: implement IRQ expecting |
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On Thu, 17 Jun 2010 17:54:48 +0200 Tejun Heo <tj@kernel.org> wrote:
> Crazy devices too but I think they would > fall in a single tick any way.
not sure what ticks have to do with anything but ok ;)
> At any rate, let's say I have those > numbers, how would I feed it into c-state selection?
if we have this, we need to put a bit of glue in the backend that tracks (per cpu I suppose) the shortest expected interrupt, which the C state code then queries. (and in that regard, it does not matter if shortest expected is computed via heuristic on a per irq basis, or passed in).
mapping an irq to a cpu is not a 100% science (since interrupts can move in theory), but just assuming that the irq will happen on the same CPU it happened last time is more than good enough.
-- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org
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