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Re: [Xen-devel] [PATCH/RFC] Wrong account for cpus other than 0 on hotplug

On Fri, Oct 13, 2006 at 09:33:53PM +0100, Keir Fraser wrote:
> On 13/10/06 6:50 pm, "Glauber de Oliveira Costa" <gcosta@xxxxxxxxxx> wrote:
> This patch turns off the missing ticks accounting entirely, as the
> runstate_info structure will never be updated. Are you sure this appears to
> be an x86_64-specific issue?

That's why I was almost sure it was wrong, and was expecting comments
Among all machines we have, it just seem to be happening in a few of
them. Besides being x86_64, they're 8-way, which can be another sort of

I just found that the offending code is in the HV itself, and not in the
guest. In arch_do_vcpu_op(), we see that the information is only passed
up to the guest, if the check (current == v) holds, which seems to be
true source of it. (taking the check away makes it work).

I can see no reason for this check to be there. If there is one, we
could maybe make sure it holds. (maybe calling set_current(v) on HV

Your comments on this are , as usual, very welcome ;-)

Glauber de Oliveira Costa
Red Hat Inc.
"Free as in Freedom"

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