HELP: cpufreq on HT and/or SMP systems

From: Ricardo Galli (gallir_at_uib.es)
Date: 07/31/03


To: linux-kernel@vger.kernel.org
Date:	Thu, 31 Jul 2003 23:53:54 +0200

I have some doubts regarding cpufreq for SMP systems (for developing
http://mnm.uib.es/~gallir/cpudyn/).

If I remember well, I read a while ago that cpufreq didn't work in SMP
systems, but reading the docs and kernel/cpufreq.c, it seems there should be
any problem?

Is it true?

OTH, I trying it on a P4 HT, and it works, changes in the frequency of one of
the "cpu's", changes both.

What happens in the case of several real cpu's? Does it keep the same
frequency for every cpu? According to a comment in cpufreq.c, it seems that
each cpu might have different frequencies.

So, what's recommended? Change the frequency of every cpu one by one?

Thanks,

PS: sorry, I don't have any cpufreq/SMP machine at hand.

-- 
  ricardo galli       GPG id C8114D34
  http://mnm.uib.es/~gallir/
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