RE: [PATCH v2 0/6] perf arm64 metricgroup support

Paul A. Clarke
2021-04-06T12:19:41Z

On Tue, Apr 06, 2021 at 12:02:36PM +0100, John Garry wrote:
> On 30/03/2021 07:41, kajoljain wrote:
> > On 3/30/21 2:37 AM, Paul A. Clarke wrote:
> > > On Fri, Mar 26, 2021 at 10:57:40AM +0000, John Garry wrote:
> > > > On 25/03/2021 20:39, Paul A. Clarke wrote:
> > > > > On Thu, Mar 25, 2021 at 06:33:12PM +0800, John Garry wrote:
> > > > > > Metric reuse support is added for pmu-events parse metric testcase.
> > > > > > This had been broken on power9 recentlty:
> > > > > > https://lore.kernel.org/lkml/20210324015418.GC8931@li-24c3614c-2adc-11b2-a85c-85f334518bdb.ibm.com/
> > > > >
> > > > > Much better. Before:
> > > > > --
> > > > > $ perf test -v 10 2>&1 | grep -i error | wc -l
> > > > > 112
> > > > > --
> > > > > After:
> > > > > --
> > > > > $ perf test -v 10 2>&1 | grep -i error | wc -l
> > > > > 17
> > > > > --
> > > > >
> > > > > And these seem like different types of issues:
> > > > > --
> > > > > $ perf test -v 10 2>&1 | grep -i error
> > > > > Error string 'Cannot find PMU `nest_mcs01_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs01_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs23_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs23_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs01_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs01_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs23_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs23_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_powerbus0_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs23_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs01_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs01_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs01_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs01_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs23_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs23_imc'. Missing kernel support?' help '(null)'
> > > > > Error string 'Cannot find PMU `nest_mcs23_imc'. Missing kernel support?' help '(null)'
> > > > > --
> > > > >
> > > >
> > > > This looks suspicious.
> > > >
> > > > Firstly, does /sys/bus/event_source/devices/nest_mcs01_imc (or others,
> > > > above) exist on your system? I guess not.
> > > >
> > > > Secondly, checking Documentation/powerpc/imc.rst, we have examples of:
> > > > nest_mcs01/PM_MCS01_64B_R...
> > > >
> > > > So is the PMU name correct in the metric file for nest_mcs01_imc? Looking at
> > > > the kernel driver file, arch/powerpc/perf/imc-pmu.c, it seems to be correct.
> > > > Not sure.
> > >
> > > I ran with a newer kernel, and the above errors disappeared, replaced with
> > > about 10 of:
> > > --
> > > Error string 'Cannot find PMU `hv_24x7'. Missing kernel support?' help '(null)'
> > > --
> > >
> > > ...but I was running without a hypervisor, so I tried the same kernel on a
> > > PowerVM-virtualized system and the "hv_24x7" messages went away, but the
> > > "nest" messages returned. This may all be expected behavior... I confess
> > > I haven't followed these new perf capabilities closely.
> > >
> >
> > Hi Paul/John,
> > This is something expected. For nest-imc we need bare-metal system and for
> > hv-24x7 we need VM environment. Since you are checking this test in VM machine,
> > there nest events are not supported and hence we are getting this error.
> >
> > Thanks,
> > Kajol Jain
>
> Cool, so I hope that tested-by or similar can be provided :) [obviously
> pending any changes that come from reviews]

Certainly!

Tested-by: Paul A. Clarke <pc@us.ibm.com>

PC