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Date: Wed, 5 Mar 2008 07:04:54 +0100
From: Pierre Ossman <drzeus-list@drzeus.cx>
To: Andi Kleen <andi@firstfloor.org>
Cc: Andi Kleen <andi@firstfloor.org>,
       "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>,
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       Lee Revell <rlrevell@joe-job.com>, linux-pm@lists.linux-foundation.org,
       Pavel Machek <pavel@ucw.cz>
Subject: Re: [linux-pm] [PATCH] cpuidle: avoid singing capacitors
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On Tue, 4 Mar 2008 19:34:06 +0100
Andi Kleen <andi@firstfloor.org> wrote:

> On Tue, Mar 04, 2008 at 07:04:46PM +0100, Pierre Ossman wrote:
> > 
> > I don't think I quite see the point. If we can't force an update, then
> > it doesn't really help us knowing if the jiffies value is stale or not.
> 
> What do you mean with force an update? The system always does an 
> jiffies update automatically after idle wakeup. It's just that if you add 
> code to the code path that uses jiffies you have to make sure it is after the 
> standard update, otherwise you'll see a stale value.
> 

I still don't follow. Perhaps you can express it in pseudo code? If I have a stale value that I cannot refresh, knowing that it is stale doesn't change anything.


-- 
     -- Pierre Ossman

  Linux kernel, MMC maintainer        http://www.kernel.org
  PulseAudio, core developer          http://pulseaudio.org
  rdesktop, core developer          http://www.rdesktop.org