linux-kernel - Re: [PATCH 3/5] cpufreq: Add APERF/MPERF support for AMD processors

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Message-Id: <201003252159.31883.trenn@suse.de>
Date:	Thu, 25 Mar 2010 21:59:31 +0100
From:	Thomas Renninger <trenn@...e.de>
To:	Valdis.Kletnieks@...edu
Cc:	Borislav Petkov <bp@...64.org>, akpm@...ux-foundation.org,
	davej@...hat.com, linux@...inikbrodowski.net, mingo@...e.hu,
	hpa@...or.com, tglx@...utronix.de, cpufreq@...r.kernel.org,
	x86@...nel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/5] cpufreq: Add APERF/MPERF support for AMD processors

On Thursday 25 March 2010 08:55:19 pm Valdis.Kletnieks@...edu wrote:
> On Thu, 25 Mar 2010 10:43:04 BST, Thomas Renninger said:
> > > +	if (c->cpuid_level >= 6) {
> >
> > and remove this (arch/x86/kernel/cpu/intel.c):
> >         if (c->cpuid_level > 6) {
>
> So is > or >= the correct comparator here?

This one: >= is correct (for both).
I double checked, there is one Intel CPU type
having a cpuid_level of 6, but this would not support aperf/mperf, thus
above is still fine.

The remaining question is what Borislav said:
are there other x86 CPU vendors who could use this differently.
I very much expect there are not.

IMO you should resubmit this one or the whole series with this change
and Dave should just push this in his tree and queue it up, there was enough
time to object.

Thanks,

      Thomas
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