Re: [Qemu-devel] [RFC 0/5] Allow object-add on X86CPU subclasses, for CPU model probing

[Eduardo Habkost]

On Fri, May 16, 2014 at 04:52:21PM +0200, Igor Mammedov wrote:
> On Thu, 15 May 2014 11:03:49 -0300
> Eduardo Habkost <address@hidden> wrote:
> > On Thu, May 15, 2014 at 03:48:16PM +0200, Igor Mammedov wrote:
[...]
> > > 
> > > Can't we add query-cpus QMP command or something like this to hide path
> > > from user.
> > 
> > That would work, too. But why is a dedicated "query-cpus" command better
> > than something like "qom-list path=/machine/cpus" (that could simply
> > return a list of links to the actual CPU objects)?
> So that not to stall the work on deciding on
>  - if exposing not yet stables QOM paths as stable ABI is a good thing, I
>    recall Andreas objecting to using QOM paths with device hotplug

This surprises me.

>  - what paths to CPUs should be wrt stalled topology discussion
> 

I don't see why it depends on the topology discussion: if we are capable
of keeping "query-cpus" working after we introduce the topology
hierarchy, I believe we are perfectly capable of keeping symlinks on
"/machine/cpus" working, too. Even if we change the actual paths later
and introduce a more complex QOM hierarchy somewhere else.

Isn't the reuse of infrastructure for list/get/set operations the whole
point of QOM?

-- 
Eduardo