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Re: [Xen-devel] irq_guest_eoi_timer interaction with MSI

To: Jan Beulich <jbeulich@xxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] irq_guest_eoi_timer interaction with MSI
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Thu, 13 Nov 2008 11:22:51 +0000
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Oh yes, and indeed this could be stashed at the end of shared_info. We could
reserve another bitmap of, say, 1024 bits quite easily. Plenty of PIRQs!

 -- Keir

On 13/11/08 11:16, "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx> wrote:

> We already have PHYSDEVOP_eoi. We can force guests to always use that. It'll
> be no slower than level-triggered IO-APIC IRQs, which we've been using since
> forever with no complaints. And yeah, as an extension we could have a
> shared-memory pirq bitmap to indicate dynamically whether eoi is required.
> Quite a secondary concern though, I would say.



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