Re: [Qemu-devel] KVM call agenda for Tuesday 7

[Andreas Färber]

Am 07.02.2012 19:01, schrieb Anthony Liguori:
> On 02/07/2012 07:45 AM, Andreas Färber wrote:
>> http://lists.gnu.org/archive/html/qemu-devel/2012-01/msg04065.html
>>
>> How is the realize step (DeviceState::init) supposed to translate to
>> Object-derived classes (e.g., CPU) and where to draw the line between
>> initfn and realize.
> 
> Realize probably should be folded into Object or some intermediate object.
> 
> The idea is that there will be a realized boolean property.  When the
> level changes, it will invoke a realize() or unrealize() method
> depending on the direction.  DeviceState will implement realize() and
> invoke init().  For unrealize(), it will invoke exit().

That's fine. Question is, who is in charge of setting the realized
property and some rules of what do we put in initfn and what in realize.
Take the CPU, should CPU reset be done in realize or initfn? realize
might overwrite values set by the user after initfn but would provide us
with a reproducible state wrt reboot.

Starting the VCPU thread would definitely be for realize, but currently
this is all done from cpu_*_init() and having sequential calls to initfn
and realize doesn't offer any advantage over doing it all in initfn.

So given we do the split, who knows about these objects to call their
realize function? Will there be some global QOM logic that calls realize
on all objects instantiated so far (any ordering constraints then?) or
is everyone themselves responsible for making this work, i.e. must I
keep a global list of all CPUs initfn'ed to have their realize method
called later?

Andreas

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