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Date: Fri, 4 Dec 2015 09:51:02 -0800
From: Jacob Pan <jacob.jun.pan@linux.intel.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@alien8.de>,
        Amy Wiles <amy.l.wiles@intel.com>,
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        LKML <linux-kernel@vger.kernel.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>, jacob.jun.pan@linux.intel.com
Subject: Re: [PATCH] x86/rapl: Do not load in a guest
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On Fri, 4 Dec 2015 09:22:56 +0100
Peter Zijlstra <peterz@infradead.org> wrote:

> Also, yuck @ powercap/intel_rapl.c for doing rdmsr_on_cpu() +
> wrmsr_on_cpu() all over the place.
Can you please be more specific? is the concern related to the
overhead of IPI? I am doing these calls based on MSR CPU scope and
consider the fact that access is less frequent.

Thanks,

Jacob