Re: [PATCH 2/2] perf test: Add basic stat and topdown group test

[Liang, Kan]

On 5/5/2022 11:22 AM, Ian Rogers wrote:
> On Thu, May 5, 2022 at 5:12 AM Liang, Kan <kan.liang@xxxxxxxxxxxxxxx> wrote:
> > On 5/5/2022 12:38 AM, Ian Rogers wrote:
> > > Add a basic stat test.
> > > Add two tests of grouping behavior for topdown events. Topdown events
> > > are special as they must be grouped with the slots event first.
> > >
> > > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> > > ---
> > >    tools/perf/tests/shell/stat.sh | 65 ++++++++++++++++++++++++++++++++++
> > >    1 file changed, 65 insertions(+)
> > >    create mode 100755 tools/perf/tests/shell/stat.sh
> > >
> > > diff --git a/tools/perf/tests/shell/stat.sh b/tools/perf/tests/shell/stat.sh
> > > new file mode 100755
> > > index 000000000000..80869ea6debc
> > > --- /dev/null
> > > +++ b/tools/perf/tests/shell/stat.sh
> > > @@ -0,0 +1,65 @@
> > > +#!/bin/sh
> > > +# perf stat tests
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +
> > > +set -e
> > > +
> > > +err=0
> > > +test_default_stat() {
> > > +  echo "Basic stat command test"
> > > +  if ! perf stat true 2>&1 | egrep -q "Performance counter stats for 'true':"
> > > +  then
> > > +    echo "Basic stat command test [Failed]"
> > > +    err=1
> > > +    return
> > > +  fi
> > > +  echo "Basic stat command test [Success]"
> > > +}
> > > +
> > > +test_topdown_groups() {
> > > +  # Topdown events must be grouped with the slots event first. Test that
> > > +  # parse-events reorders this.
> > > +  echo "Topdown event group test"
> > > +  if ! perf stat -e '{slots,topdown-retiring}' true > /dev/null 2>&1
> > > +  then
> > > +    echo "Topdown event group test [Skipped event parsing failed]"
> > > +    return
> > > +  fi
> > > +  if perf stat -e '{slots,topdown-retiring}' true 2>&1 | egrep -q "<not supported>"
> > > +  then
> > > +    echo "Topdown event group test [Failed events not supported]"
> > > +    err=1
> > > +    return
> > > +  fi
> > > +  if perf stat -e '{topdown-retiring,slots}' true 2>&1 | egrep -q "<not supported>"
> > > +  then
> > > +    echo "Topdown event group test [Failed slots not reordered first]"
> > > +    err=1
> > > +    return
> > > +  fi
> > > +  echo "Topdown event group test [Success]"
> > > +}
> > > +
> > > +test_topdown_weak_groups() {
> > > +  # Weak groups break if the perf_event_open of multiple grouped events
> > > +  # fails. Breaking a topdown group causes the events to fail. Test a very large
> > > +  # grouping to see that the topdown events aren't broken out.
> > > +  echo "Topdown weak groups test"
> > > +  if ! perf stat -e '{slots,topdown-bad-spec,topdown-be-bound,topdown-fe-bound,topdown-retiring},branch-instructions,branch-misses,bus-cycles,cache-misses,cache-references,cpu-cycles,instructions,mem-loads,mem-stores,ref-cycles,baclears.any,ARITH.DIVIDER_ACTIVE' true > /dev/null 2>&1
> > > +  then
> > > +    echo "Topdown weak groups test [Skipped event parsing failed]"
> > > +    return
> > > +  fi
> > > +  if perf stat -e '{slots,topdown-bad-spec,topdown-be-bound,topdown-fe-bound,topdown-retiring,branch-instructions,branch-misses,bus-cycles,cache-misses,cache-references,cpu-cycles,instructions,mem-loads,mem-stores,ref-cycles,baclears.any,ARITH.DIVIDER_ACTIVE}:W' true 2>&1 | egrep -q "<not supported>"
> > > +  then
> > > +    echo "Topdown weak groups test [Failed events not supported]"
> > > +    err=1
> > > +    return
> > > +  fi
> > > +  echo "Topdown weak groups test [Success]"
> > > +}
> > > +
> >
> > Should we check the existence of the slots event before the test?
> > The perf metrics feature only be available on the new platform after
> > ICL. It doesn't work on Atom.
> >
> > Also, I think the test may fails on the hybrid platform, since big core
> > and small core have different formula for the topdown. I think we should
> > avoid the test for the hybrid platform for now.
> > +Zhengjun, who is fixing the topdown gap for the hybrid platform. I
> > think he may take care of the hybrid support later.
>
> Thanks Kan, the test filters out systems that don't support the events
> and silently skips the test. The main purpose of the test is to make
> sure the somewhat complicated grouping operations for Icelake have
> some coverage. Adding more coverage for hybrid would be great, but not
> something I think gates this change.

Sure, we can add the coverage for hybrid later. But please make sure the 
test can filter out both the systems which doesn't support perf metircs 
and the hybrid system.

Thanks,
Kan

> Thanks,
> Ian
>
> > Thanks,
> > Kan
> > > +test_default_stat
> > > +test_topdown_groups
> > > +test_topdown_weak_groups
> > > +exit $err