Re: [PATCH 09/12] irq: implement IRQ expecting

[Arjan van de Ven]

On Thu, 17 Jun 2010 17:54:48 +0200
Tejun Heo <tj@xxxxxxxxxx> 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
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