Subject: Re: [PATCH v2 5/6] KVM-GST: adjust scheduler cpu power
From: Peter Zijlstra <peterz@infradead.org>
To: Glauber Costa <glommer@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, aliguori@us.ibm.com,
        Rik van Riel <riel@redhat.com>,
        Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>,
        Avi Kivity <avi@redhat.com>
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Date: Tue, 01 Feb 2011 17:19:28 +0100
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On Tue, 2011-02-01 at 13:59 -0200, Glauber Costa wrote:
> 
> Because that part is kvm-specific, and this is scheduler general.
> It seemed cleaner to me to do it this way. But I can do it differently,
> certainly. 

Well, any steal time clock will be hypervisor specific, but if we agree
that anything that enables CONFIG_PARAVIRT_TIME_ACCOUNTING provides a
u64 steal_time_clock(int cpu) function then all should be well, right?

The bit you have in kvm is almost that, except it assumes cpu ==
this_cpu.

You simply cannot rely on the silly tick accounting to drive any clock,
its archaic.


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