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Date: Wed, 14 Mar 2007 13:59:51 -0700
From: Jeremy Fitzhardinge <jeremy@goop.org>
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To: Ingo Molnar <mingo@elte.hu>
CC: Dan Hecht <dhecht@vmware.com>, dwalker@mvista.com,
       cpufreq@lists.linux.org.uk,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Con Kolivas <kernel@kolivas.org>, Chris Wright <chrisw@sous-sol.org>,
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       john stultz <johnstul@us.ibm.com>, Thomas Gleixner <tglx@linutronix.de>,
       paulus@au.ibm.com, schwidefsky@de.ibm.com,
       Rik van Riel <riel@redhat.com>
Subject: Re: Stolen and degraded time and schedulers
References: <45F6D1D0.6080905@goop.org> <1173816769.22180.14.camel@localhost> <45F70A71.9090205@goop.org> <1173821224.1416.24.camel@dwalker1> <45F71EA5.2090203@goop.org> <45F74515.7010808@vmware.com> <45F77C27.8090604@goop.org> <45F846AB.6060200@vmware.com> <45F84E39.7030507@goop.org> <20070314203826.GA15394@elte.hu>
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Ingo Molnar wrote:
> touching the 'timer tick' is the wrong approach. 'stolen time' only 
> matters to the /scheduler tick/. So extend the hypervisor interface to 
> allow the injection of 'virtual' scheduler tick events: via the use of a 
> special clockevents device - do not change clockevents itself.

I didn't.  I was using sloppy terminology: I hang the stolen time
accounting off the Xen timer interrupt routine, just so that it gets run
every now and again.

I suppose I could explicitly hook stolen time accounting into the
scheduler, but its not obvious to me that it's necessary.

    J