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Date: Mon, 24 May 2010 20:57:11 +0200
From: Pavel Machek <pavel@ucw.cz>
To: Arve Hj?nnev?g <arve@android.com>
Cc: James Kosin <james.kosin.04@cnu.edu>, linux-kernel@vger.kernel.org
Subject: Re: [linux-pm] [PATCH 1/8] PM: Add suspend block api.
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> >> One if the benefit we get from using suspend is that an unprivileged
> >> app that does not have access to suspend blockers cannot prevent
> >> suspend. You lose this advantage if you trigger suspend only from the
> >> idle task.
> >>
> >>
> > If the process (privileged or unprivileged) doesn't want to suspend, why
> > not just provide an interface to allow suspend to be turned off at the
> > user level.  This could block the suspend cycle in itself, and you
> > shouldn't need fine grained off/on cycles.  If an application really
> > needs the system not to suspend then they (the user) should know the
> > consequences and power requirements for such a task.
> >
> > I didn't say it had to be only from the idle task; but, that is the most
> > logical place.  If the other threads are not idle then they really
> > require work and will most likely already have a bock on the suspend anyway.
> >
> 
> I think you missed my point. Unprivileged processes should not be
> allowed to prevent suspend.

Currently, unpriviledged processes are allowed to eat power, for
example while(1). We should keep that behaviour at least by default.

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html