[libvirt] [PATCH 6/8] qemu_driver: add support to perf event

[Ren, Qiaowei]

> -----Original Message-----
> From: Jiri Denemark [mailto:jdenemar at redhat.com]
> Sent: Monday, November 30, 2015 7:09 PM
> To: Ren, Qiaowei
> Cc: libvir-list at redhat.com
> Subject: Re: [libvirt] [PATCH 6/8] qemu_driver: add support to perf event
> 
> On Mon, Nov 30, 2015 at 08:17:05 +0000, Ren, Qiaowei wrote:
> >
> > > -----Original Message-----
> > > From: Jiri Denemark [mailto:jdenemar at redhat.com]
> > > Sent: Tuesday, November 24, 2015 9:01 PM
> > > To: Ren, Qiaowei
> > > Cc: libvir-list at redhat.com
> > > Subject: Re: [libvirt] [PATCH 6/8] qemu_driver: add support to perf
> > > event
> > >
> > > On Tue, Nov 17, 2015 at 16:00:46 +0800, Qiaowei Ren wrote:
> > > > This patch implement the internal driver API for perf event into
> > > > qemu driver.
> > > >
> > > > In addition, this patch extend virDomainListGetStats API to get
> > > > the statistics for perf event. To do so, we add a
> 'VIR_DOMAIN_STATS_PERF'
> > > > enum to causes reporting of all previously enabled perf events.
> > > >
> > > > Signed-off-by: Qiaowei Ren <qiaowei.ren at intel.com>
> > > > ---
> > > >  include/libvirt/libvirt-domain.h |   1 +
> > > >  src/qemu/qemu_domain.h           |   3 +
> > > >  src/qemu/qemu_driver.c           | 181
> > > +++++++++++++++++++++++++++++++++++++++
> > > >  #define QEMU_SCHED_MIN_PERIOD              1000LL
> > > >  #define QEMU_SCHED_MAX_PERIOD           1000000LL
> > > >  #define QEMU_SCHED_MIN_QUOTA               1000LL
> > > > @@ -10244,6 +10247,106 @@
> > > qemuDomainGetNumaParameters(virDomainPtr
> > > > dom,  }
> > > >
> > > >  static int
> > > > +qemuDomainSetPerfEvents(virDomainPtr dom,
> > > > +                        virTypedParameterPtr params,
> > > > +                        int nparams) {
> > > > +    size_t i;
> > > > +    virDomainObjPtr vm = NULL;
> > > > +    qemuDomainObjPrivatePtr priv;
> > > > +    int ret = -1;
> > > > +    bool enabled;
> > > > +
> > > > +    if (virTypedParamsValidate(params, nparams,
> > > > +                               VIR_DOMAIN_PERF_CMT,
> > > > +                               VIR_TYPED_PARAM_BOOLEAN,
> > > > +                               NULL) < 0)
> > > > +        return -1;
> > >
> > > Use virTypedParamsCheck and define the data for it in virperf.h so
> > > that you don't need to change the code here if new event type is added.
> > >
> >
> > Jirka, I checked the difference between virTypedParamsValidate and
> > virTypedParamsCheck, and found that virTypedParamsCheck just check
> > whether the param is valid through param name, but
> > virTypedParamsValidate will check whether the param type is right.
> 
> Oh, sorry for the confusion then. I actually wanted the code to be something like
> 
>     if (virTypedParamsValidate(params, nparams, VIR_PERF_PARAMS) < 0)
>         return -1;
> 
> and VIR_PERF_PARAMS would be a macro defined in virparams.h:
> 
> # define VIR_PERF_PARAMS \
>     VIR_DOMAIN_PERF_CMT, VIR_TYPED_PARAM_BOOLEAN, \
>     NULL
> 
> Similar to QEMU_MIGRATION_PARAMETERS and few others.
> 

Got it! Thanks, Jirka.

Qiaowei