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Re: [Xen-devel] increase evtchn limits

To: Jan Beulich <jbeulich@xxxxxxxxxx>, "mukesh.rathor@xxxxxxxxxx" <mukesh.rathor@xxxxxxxxxx>
Subject: Re: [Xen-devel] increase evtchn limits
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Fri, 21 May 2010 10:29:03 +0100
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On 21/05/2010 10:25, "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx> wrote:

>> There are 5 event channels per CPU (timer, reschedule IPI, SMP call function
>> IPI, SMP call function single IPI, and spinlock wakeup IPI).

It would be very easy to collapse the four IPIs onto one event channel plus
a bitmask of IPI reasons. Then that would be a much more economical two
event channels per CPU. And the change is a hell of a lot easier to
implement than extensible event channels. I bet it could be knocked together
in an hour.

 -- Keir

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