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Re: [Xen-devel] x86's context switch ordering of operations

To: Jan Beulich <jbeulich@xxxxxxxxxx>
Subject: Re: [Xen-devel] x86's context switch ordering of operations
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Tue, 29 Apr 2008 17:52:51 +0100
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On 29/4/08 16:37, "Jan Beulich" <jbeulich@xxxxxxxxxx> wrote:

> Okay, that could be easily dealt with by doing set_current() explicitly
> in the switch-to-idle case, and moving it into __context_switch() in
> the other cases.

It wouldn't really help you. If you switch to from VCPU A to idle and then
to VCPU B, you would still end up calling ctxt_switch_from(A) when

> Any word on the significance of doing write_ptbase() after calling
> ctxt_switch_to()?

It probably could be done earlier.

 -- Keir

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