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Re: [Xen-devel] vgettimeofday disabled?

To: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] vgettimeofday disabled?
From: Chris Lalancette <clalance@xxxxxxxxxx>
Date: Wed, 03 Sep 2008 18:02:06 +0200
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Keir Fraser wrote:
> We probably don't update vxtime structure, so you likely get dodgy results
> from do_vgettimedofday(). However, forcing vxtime to track vcpu0's time info
> obtained from Xen would probably be quite easy to do and may be accurate
> enough.
> But, without that extra engineering, I recommend you check what answers
> you're getting from gettimeofday(). Could be quite a significant
> performance/correctness tradeoff ;-)

Ah, OK.  So there's not really a fundamental issue (which I was worried about),
more just it hasn't been implemented all the way.  Interestingly, it doesn't
seem to be explicitly disabled in the LKML pv_ops implementation, so either it's
being updated properly there, or time is *way* off.

Thanks for the info.

Chris Lalancette

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