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Subject: Re: [PATCH] cpuidle/powernv: Enter fastsleep on checking if deep
 idle states are allowed
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>, mikey@neuling.org,
        linux-pm@vger.kernel.org, rjw@rjwysocki.net,
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Date: Mon, 15 Sep 2014 08:23:16 -0400
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On Mon, 2014-09-15 at 14:22 +0530, Preeti U Murthy wrote:
> > We were talking about getting rid of powersave_nap altogether, but I
> think we
> > decided we couldn't, I forget.
> 
> Isn't this a helpful knob to disable cpuidle at runtime? Currently we
> check the value of powersave_nap before entering both nap and
> fastsleep.

It's useful when diagnosing some problems that can be caused by idle
states.

Cheers,
Ben.