Re: [PATCH 3/8] qmp: add filtering of statistics by target vCPU

[Paolo Bonzini]

On 5/5/22 15:45, Markus Armbruster wrote:
> Paolo Bonzini <pbonzini@redhat.com> writes:
>
> > Introduce a simple filtering of statistics, that allows to retrieve
> > statistics for a subset of the guest vCPUs.  This will be used for
> > example by the HMP monitor, in order to retrieve the statistics
> > for the currently selected CPU.
> >
> > Example:
> > { "execute": "query-stats",
> >    "arguments": {
> >      "target": "vcpu",
> >      "vcpus": [ "/machine/unattached/device[2]",
> >                 "/machine/unattached/device[4]" ] } }
>
> What heartless people put these poor vCPUs in the orphanage?

Phil tried to fix it but the testsuites hung in weird ways.

Paolo

> > Extracted from a patch by Mark Kanda.
> >
> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
>
> [...]
>
> > diff --git a/qapi/stats.json b/qapi/stats.json
> > index bcc897258a..26ee69588f 100644
> > --- a/qapi/stats.json
> > +++ b/qapi/stats.json
> > @@ -65,6 +65,16 @@
> >   { 'enum': 'StatsTarget',
> >     'data': [ 'vm', 'vcpu' ] }
> >   
> > +##
> > +# @StatsVCPUFilter:
> > +#
> > +# @vcpus: list of qom paths for the desired vCPU objects.
>
> "QOM paths", because that's how we spell it elsewhere.
>
> > +#
> > +# Since: 7.1
> > +##
> > +{ 'struct': 'StatsVCPUFilter',
> > +  'data': { '*vcpus': [ 'str' ] } }
> > +
> >   ##
> >   # @StatsFilter:
> >   #
> > @@ -73,8 +83,10 @@
> >   #
> >   # Since: 7.1
> >   ##
> > -{ 'struct': 'StatsFilter',
> > -  'data': { 'target': 'StatsTarget' } }
> > +{ 'union': 'StatsFilter',
> > +        'base': { 'target': 'StatsTarget' },
> > +  'discriminator': 'target',
> > +  'data': { 'vcpu': 'StatsVCPUFilter' } }
> >   
> >   ##
> >   # @StatsValue: