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

John Garry
2021-03-26T11:01:05Z

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.

Thanks,
John

> (Added Kajol Jain to CC)
>