linux-kernel - Re: [PATCH v4 12/12] perf test: improve pmu event metric testing

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Message-ID: <CAP-5=fVaLWVyxweesWYCj1=FFubM3t6OsF1Jd46d=FtsQUQVmQ@mail.gmail.com>
Date:   Sun, 3 May 2020 10:31:37 -0700
From:   Ian Rogers <irogers@...gle.com>
To:     Jiri Olsa <jolsa@...hat.com>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Namhyung Kim <namhyung@...nel.org>,
        Kan Liang <kan.liang@...ux.intel.com>,
        Andi Kleen <ak@...ux.intel.com>,
        Haiyan Song <haiyanx.song@...el.com>,
        Jin Yao <yao.jin@...ux.intel.com>,
        Song Liu <songliubraving@...com>,
        Ravi Bangoria <ravi.bangoria@...ux.ibm.com>,
        John Garry <john.garry@...wei.com>,
        Leo Yan <leo.yan@...aro.org>,
        Adrian Hunter <adrian.hunter@...el.com>,
        Paul Clarke <pc@...ibm.com>,
        LKML <linux-kernel@...r.kernel.org>,
        kajoljain <kjain@...ux.ibm.com>,
        linux-perf-users <linux-perf-users@...r.kernel.org>,
        Stephane Eranian <eranian@...gle.com>
Subject: Re: [PATCH v4 12/12] perf test: improve pmu event metric testing

On Sun, May 3, 2020 at 10:06 AM Jiri Olsa <jolsa@...hat.com> wrote:
>
> On Sun, May 03, 2020 at 08:26:22AM -0700, Ian Rogers wrote:
> > On Sun, May 3, 2020 at 7:56 AM Jiri Olsa <jolsa@...hat.com> wrote:
> > >
> > > On Fri, May 01, 2020 at 10:33:33AM -0700, Ian Rogers wrote:
> > > > Add a basic floating point number test to expr.
> > > > Break pmu-events test into 2 and add a test to verify that all pmu metric
> > > > expressions simply parse. Try to parse all metric ids/events, failing if
> > > > metrics for the current architecture fail to parse.
> > > >
> > > > Tested on skylakex with the patch set in place. May fail on other
> > > > architectures if metrics are invalid.
> > >
> > > yep, failing for me (-vvv output below).. could you plz
> > > detect that and skip the test ?
> >
> > Thanks, filtering the verbose output we have just 1 parse event failure:
> >
> > Parse event failed: id 'arb/event=0x80,umask=0x2,thresh=1/' metric
> > 'DRAM_Parallel_Reads' expr 'arb@...nt\=0x80\,umask\=0x2@ /
> > arb@...nt\=0x80\,umask\=0x2\,thresh\=1@'
> > Error string 'unknown term 'thresh' for pmu 'uncore_arb'' help 'valid
> > terms: event,edge,inv,umask,cmask,config,config1,config2,name,period,freq,branch_type,time,call-graph,stack-size,no-inherit,inherit,max-stack,nr,no-overwrite,overwrite,driver-config,percore,aux-output,aux-sample-size'
> >
> > This looks like a bug in skl-metrics.json:
> >
> >    {
> >         "BriefDescription": "Average number of parallel data read
> > requests to external memory. Accounts for demand loads and L1/L2
> > prefetches",
> >         "MetricExpr": "arb@...nt\\=0x80\\,umask\\=0x2@ /
> > arb@...nt\\=0x80\\,umask\\=0x2\\,thresh\\=1@",
> >         "MetricGroup": "Memory_BW",
> >         "MetricName": "DRAM_Parallel_Reads"
> >     },
> >
> > which can be fixed by removing "\\,thresh\\=1" but looking at the
> > expression this will just make the expression yield a value of 1. As
> > this is an Intel json file could they comment? Jiri, could you be
> > missing a patch on the kernel side? We could lower this failure to
> > just a diagnostic message to land this set of patches, let me know
> > what you'd like me to do.
>
> I applied this on current Arnaldo's perf/core.. not sure there's
> more pending changes out there
>
> I'd like not to delay this patchset too long.. could we push the
> first 10 patches and solve the rest in separate change?

Thanks, I've attached a patch that can be squashed into 12 to make the
error non-fatal. Patch 11 is trying to make the diagnostics around
adding a PMU event clearer and aside warning messages, and removal of,
has no functional effect. I don't mind the first 10 being merged and
these coming later. I don't mind just patch 11 coming later as it'd be
nice to have the test so metrics can get fixed.

Thanks,
Ian

> thanks,
> jirka
>

View attachment "jiri.patch" of type "text/x-patch" (1420 bytes)