Re: [RFC PATCH 11/11] nohz,kvm,time: teach account_process_tick about guest time

[Andy Lutomirski]

On Wed, Jun 24, 2015 at 7:58 AM,  <riel@xxxxxxxxxx> wrote:
> From: Rik van Riel <riel@xxxxxxxxxx>
>
> When tick based accounting is run from a remote CPU, it is actually
> possible to encounter a task with PF_VCPU set. Make sure to account
> those as guest time.

Why do we have PF_VCPU and CONTEXT_GUEST?  What's the difference
between them (other than the fact that one is per-task and one is
per-cpu)?  It would be a bit easier to understand if there were fewer
of these things.

If the issue is that remote sampling would otherwise have a race that
could account guest time to the wrong task, then maybe PF_VCPU makes
sense.  Hmm.

--Andy
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