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
current==idle.

> 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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