On Mon, 7 Mar 2016 11:02:11 +0100 David Hildenbrand <d...@linux.vnet.ibm.com> wrote:
> > > After all the discussions about > > > -device-add s390-cpu,id=XX > > > > > > As substitute/addition in the future for hotplug it is the straightforward > > > approach to allow setting the id as property. Nobody knows what crazy new > > > hotplug method we will come up with. But doing it the device way with > > > properties > > > cannot be wrong. And the id is a fundamental concept of a vcpu (cpu-add > > > id=XX). > > with device_add 'id' is not a vcpu concept but and arbitrary user supplied > > string > > property owned by Device. But since s390 matches current x86 thread based > > model it could be migrated to device_add the same way, for example: > > device_add s390-cpu,thread=XX > > So should we name the property thread then? > Looks like the id property is really special. > > What do you suggest? I plan to add 'thread' property to x86-cpu, so you could the same for s390 when the time for device_add comes there. > > > > > > > > > So I'd like to avoid reworking everything again, to realize later that we > > > want it as a property and rewriting it once again. > > for s390, the thing about not rewriting everything once again could be > > replacing places where cpu_index is used with CpuClass.arch_id(). > > arch_id() defaults to cpu_index but you can later override it with > > your own id (whatever s390 uses for identifying cpus on baremetal) > > so switching to device_add won't break anything. > > Okay, this way we could get rid of cpu_index later. > > David > >
