From mboxrd@z Thu Jan  1 00:00:00 1970
From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Subject: Re: [PATCH] qemu-kvm: response to SIGUSR1 to start/stop a VCPU (v2)
Date: Thu, 2 Dec 2010 21:14:38 +0530
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Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Anthony Liguori <aliguori@linux.vnet.ibm.com>,
	qemu-devel@nongnu.org, kvm@vger.kernel.org,
	Chris Wright <chrisw@sous-sol.org>,
	Ingo Molnar <mingo@elte.hu>, Mike Galbraith <efault@gmx.de>,
	Rik van Riel <riel@redhat.com>
To: Avi Kivity <avi@redhat.com>
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On Thu, Dec 02, 2010 at 05:33:40PM +0200, Avi Kivity wrote:
> A0 and A1's vruntime will keep growing, eventually B will become
> leftmost and become runnable (assuming leftmost == min vruntime, not
> sure what the terminology is).

Donation (in directed yield) will cause vruntime to drop as well (thats the only
way target can get to run ahead of its scheduled time), so I still think there
are nasty issues involved here. 

Anyway, I am curious to see the directed yield implementation that Rik has - I
can comment more after I have seen that!

- vatsa