[Libvir] [PATCH] Implement SetVcpus and DomainGetMaxVcpus for qemu

[Daniel P. Berrange]

On Mon, Apr 28, 2008 at 02:38:52PM -0400, Chris Lalancette wrote:
> Cole Robinson wrote:
> > The attached patch fills in two of the vcpu functions for the qemu driver:
> > 
> > virDomainSetVcpus : set the number of vcpus the domain can use
> > virDomainGetMaxVcpus : max number of vcpus that can be assigned to the domain.
> > 
> > Code change is only in qemu_driver, as the backend stuff was already in place.
> > I also edited qemudGetMaxVcpus to ignore case when checking the passed OS
> > type, since it wasn't matching the returned results of qemudDomainGetOSType.
> 
> OK, but...
> 
> > +    if (qemudIsActiveVM(vm)) {
> > +        qemudReportError(dom->conn, dom, NULL, VIR_ERR_INTERNAL_ERROR, "%s",
> > +                         _("cannot change vcpu count of an active domain"));
> > +        return -1;
> > +    }
> 
> I'm fairly certain KVM is going to support this in the near future (if not now,
> I can't remember).  I'm not sure what libvirt's policy is about things that
> don't work now, but will potentially work in the future, is, but it seems wrong
> to disable this feature for KVM.

Once there is a monitor API to support this we'll implement support for it,
and detect the lack of the monitor command for old versions. Until then, this
is correct behaviour.

Dan.
-- 
|: Red Hat, Engineering, Boston   -o-   http://people.redhat.com/berrange/ :|
|: http://libvirt.org  -o-  http://virt-manager.org  -o-  http://ovirt.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505  -o-  F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|