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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Thu, 05 Sep 2013 21:42:32 +1000
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Subject: Re: [Qemu-devel] [RFC PATCH] spapr: support time base offset
	migration
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To: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: qemu-devel@nongnu.org, Alexander Graf <agraf@suse.de>, qemu-ppc@nongnu.org, Paolo Bonzini <pbonzini@redhat.com>, Andreas =?ISO-8859-1?Q?F=E4rber?= <afaerber@suse.de>, Paul Mackerras <paulus@samba.org>, David Gibson <david@gibson.dropbear.id.au>

On Thu, 2013-09-05 at 19:48 +1000, Alexey Kardashevskiy wrote:
> >> I do not have pure guest timebase in QEMU and I need it on the destination.
> >> But I have host timebase + offset to calculate it. And tb_offset is already
> >> in ppc_tb_t. It looked logical to me to send the existing field and add
> >> only the missing part.
> > 
> > I still don't understand. You want the guest visible timebase in the migration stream, no?
> 
> 
> Yes. I do not really understand the problem here (and I am not playing
> dump). Do you suggest sending just the guest timebase and do not send the
> host timebase and the offset (one number instead of two)? I can do that,
> makes sense, no problem, thanks for the idea.

No, we want to send the guest TB and the corresponding "time of day" so that
the target can adjust the TB based on how long the migration took.

Cheers,
Ben.