From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: [Patch 2 of 2]: PV-domain SMP performance Linux-part
Date: Fri, 19 Dec 2008 10:36:02 +0000
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>>> Juergen Gross <juergen.gross@fujitsu-siemens.com> 19.12.08 11:06 >>>
>Regarding handling this in Xen only: not to deschedule a vcpu in case of
>interrupts disabled is easy, but how would you deschedule it after =
interrupts
>are allowed again?

It's all the same as with the newly added flag of yours - it requires =
cooperation
from the guest (plus the forced de-schedule if it fails to do so). It's =
just that
you don't need to set two flags when disabling interrupts, that second =
flag
would only be needed when you want to avoid being de-scheduled for
reasons other than event delivery being disabled.

Jan