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Subject: Re: [PATCH 1/8] PM: Opportunistic suspend support.
From: Peter Zijlstra <peterz@infradead.org>
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Date: Wed, 26 May 2010 10:53:07 +0200
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On Wed, 2010-05-26 at 10:42 +0200, Peter Zijlstra wrote:
> What Dmitry proposes is that, the app _before_ it consumes the event,
> pokes at this suspend manager, it increases a blocker count, then
> consumes the event (the kernel will _not_ auto-suspend), handles it and
> then again pokes the suspend manager, this time decreasing the blocker
> count.
> 
> The suspend manager will, upon reaching a 0 block count, suspend the
> machine. If that fails, it means there's something to do, an app will
> inc, work, dec its count, and it will try again once it reaches 0 again.

Alternatively the suspend manager could simply cancel the opportunistic
suspend mode on !0, and re-instate it on 0.