Re: [Qemu-devel] [RFC/PATCH 0/1] cpu hotplug for s390

[Eduardo Habkost]

On Wed, Apr 17, 2013 at 08:06:37PM +0200, Andreas Färber wrote:
> Hi Jens,
> 
> Am 03.04.2013 08:42, schrieb Jens Freimann:
> > this is what our approach to CPU hotplug looks like.
> > With respect to Igor's CPU hotplug series, how should we proceed? 
> > Should we change the interface to 
> > qemu_system_cpu_add_notifier/qemu_system_cpu_hotplug_request/cpu-add etc?
> 
> I am wondering if my recent qdev/device_add fixes would allow to
> implement CPU hot-add via device_add for s390x?
> 
> Background is that for x86 we currently have a flat CPU core/thread
> namespace but would need to deal with sockets, cores and threads to get
> topologies right. I assume there are no such issues on s390x, so that
> the vCPU to CPUState mapping could stay 1:1?

Also: x86 has a huge number of CPU models we want to convert to separate
classes, and a huge number of configurable CPU features we want to
expose as device properties.

If we don't need any of that on s390x, I agree that it may be reasonable
to try to make device_add work.

-- 
Eduardo