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

From: John Garry <john.garry@huawei.com>
To: "Paul A. Clarke" <pc@us.ibm.com>
Cc: <will@kernel.org>, <mathieu.poirier@linaro.org>,
	<leo.yan@linaro.org>, <peterz@infradead.org>, <mingo@redhat.com>,
	<acme@kernel.org>, <mark.rutland@arm.com>,
	<alexander.shishkin@linux.intel.com>, <jolsa@redhat.com>,
	<namhyung@kernel.org>, <irogers@google.com>,
	<linuxarm@huawei.com>, <kjain@linux.ibm.com>,
	<kan.liang@linux.intel.com>, <linux-kernel@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<zhangshaokun@hisilicon.com>
Subject: Re: [PATCH v2 0/6] perf arm64 metricgroup support
Date: Fri, 26 Mar 2021 10:57:40 +0000	[thread overview]
Message-ID: <dc17013d-2dcb-8ddf-a15a-e98cad3e2ae3@huawei.com> (raw)
In-Reply-To: <20210325203944.GD8931@li-24c3614c-2adc-11b2-a85c-85f334518bdb.ibm.com>

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)
> 