Re: [Qemu-devel] [RFC PATCH] spapr: support time base offset migration

[Alexey Kardashevskiy]

On 09/05/2013 09:42 PM, Benjamin Herrenschmidt wrote:
> 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.

Nobody is discussing time_of_the_day, it is there and transmitted. The only
question is whether to send host_timebase and tb_offset (2 values) or just
guest timebase (1 value).


-- 
Alexey