linux-kernel - Re: [PATCH 2/5] acpi-cpufreq: Add support for disabling dynamic overclocking

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Message-id: <alpine.LFD.2.02.1108021618190.25237@x980>
Date:	Tue, 02 Aug 2011 16:21:16 -0400 (EDT)
From:	Len Brown <lenb@...nel.org>
To:	Matthew Garrett <mjg@...hat.com>
Cc:	linux-kernel@...r.kernel.org, borislav.petkov@....com,
	davej@...hat.com, mark.langsdorf@....com, cpufreq@...r.kernel.org
Subject: Re: [PATCH 2/5] acpi-cpufreq: Add support for disabling dynamic
 overclocking

While this patch will work and is not invalid, I don't like it.

It advertises a user I/F that suggests that disabling turbo
is on a per logical processor basis -- but a write to
any of the attributes will write to every CPU in the system.

Either it should do per-cpu limiting (which, btw doesn't
work if you use the MISC_ENABLES MSR method in this patch,
and would instead need to use the PERF_CTL.32 method)
or there should be a per-system attribute
that reflects that this knob is per-system.

thanks,
Len Brown, Intel Open Source Technology Center

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