linux-kernel - Re: [PATCH 3/6 v4] cpufreq: tolerate inexact values when collecting stats

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Message-ID: <50A2766D.6040008@calxeda.com>
Date:	Tue, 13 Nov 2012 10:33:49 -0600
From:	Mark Langsdorf <mark.langsdorf@...xeda.com>
To:	Borislav Petkov <bp@...en8.de>
CC:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"cpufreq@...r.kernel.org" <cpufreq@...r.kernel.org>,
	"linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
	MyungJoo Ham <myungjoo.ham@...il.com>
Subject: Re: [PATCH 3/6 v4] cpufreq: tolerate inexact values when collecting
 stats

On 11/13/2012 10:24 AM, Borislav Petkov wrote:
> On Mon, Nov 12, 2012 at 10:35:49AM -0600, Mark Langsdorf wrote:
>> The function is buried pretty deep in the cpufreq_stat code. It didn't
>> seem appropriate to make it a function pointer as part of struct
>> cpufreq_driver.
> 
> Right, what's cpufreq-speak for
> 
> 	if (Calxeda)
> 		shift by 10
> 
> ?
> 
> Better yet, add a flag or a bitfield called "minimize_jitter" or similar
> and set it only on your hardware...

Doing it in two passes has a similar effect: systems that have exact
frequencies will get caught in the first pass when the values match. But
adding a flag makes sense.

--Mark Langsdorf
Calxeda, Inc.

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