From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: Stolen and degraded time and schedulers
Date: Wed, 14 Mar 2007 13:59:51 -0700
Message-ID: <45F86247.40109@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>, Virtualization Mailing List <virtualization@lists.osdl.org>, 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>
List-Id: virtualization@lists.linuxfoundation.org

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