Date: Sat, 19 Jun 2010 13:07:30 -0700
From: Arjan van de Ven <arjan@infradead.org>
To: Andi Kleen <andi@firstfloor.org>
Cc: Tejun Heo <tj@kernel.org>, mingo@elte.hu, tglx@linutronix.de,
       bphilips@suse.de, yinghai@kernel.org, akpm@linux-foundation.org,
       torvalds@linux-foundation.org, linux-kernel@vger.kernel.org,
       jeff@garzik.org, linux-ide@vger.kernel.org, stern@rowland.harvard.edu,
       gregkh@suse.de, khali@linux-fr.org
Subject: Re: [PATCH 09/12] irq: implement IRQ expecting
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On Sat, 19 Jun 2010 21:49:37 +0200
Andi Kleen <andi@firstfloor.org> wrote:

> > Here we have the opportunity to get real good information.. we KNOW
> > now an interrupt is coming, and we can even estimate how long it'll
> > be...  Even for the first few after a long time, before a pattern
> > emerges.
> 
> Ok but I thought the driver would just fill in a single number 
> likely. Is that really that good information?

Tejun suggested tracking this per handler, I'm assuming that instead of
the driver passed number

> 
> Alternatively each driver would need to implement some dynamic
> estimation algorithm, but that would be just mostly equivalent
> to having it all in the idle governour?

that's the whole point... let the irq layer track this stuff, and
inform the governor. the governor does not know irqs are expected..
with tejun's change, the irq layer at least will.


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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