Re: [PATCH] perf test: Basic branch counter support

["Liang, Kan" <kan.liang@linux.intel.com>]

On 2023-11-07 1:05 p.m., Ian Rogers wrote:
> On Tue, Nov 7, 2023 at 9:44 AM <kan.liang@linux.intel.com> wrote:
>>
>> From: Kan Liang <kan.liang@linux.intel.com>
>>
>> Add a basic test for the branch counter feature.
>>
>> The test verifies that
>> - The new filter can be successfully applied on the supported platforms.
>> - The counter value can be outputted via the perf report -D
>>
>> Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
> 
> Thanks Kan!
> 
>> ---
>>  tools/perf/tests/shell/record.sh | 30 ++++++++++++++++++++++++++++++
>>  1 file changed, 30 insertions(+)
>>
>> diff --git a/tools/perf/tests/shell/record.sh b/tools/perf/tests/shell/record.sh
>> index 4fbc74805d52..2783e867c07c 100755
>> --- a/tools/perf/tests/shell/record.sh
>> +++ b/tools/perf/tests/shell/record.sh
>> @@ -11,6 +11,9 @@ err=0
>>  perfdata=$(mktemp /tmp/__perf_test.perf.data.XXXXX)
>>  testprog="perf test -w thloop"
>>  testsym="test_loop"
>> +cpu_pmu_dir="/sys/bus/event_source/devices/cpu*"
>> +br_cntr_file="/caps/branch_counter_nr"
>> +br_cntr_output="branch stack counters"
>>
>>  cleanup() {
>>    rm -rf "${perfdata}"
>> @@ -154,10 +157,37 @@ test_workload() {
>>    echo "Basic target workload test [Success]"
>>  }
>>
>> +test_branch_counter() {
>> +  echo "Basic branch counter test"
>> +  # Check if the branch counter feature is supported
> 
> If $cpu_pmu_dir is empty, e.g. ARM and S390, this should also skip.
> 

Yes, I've tested with a fake unsupported dir. The test case is skipped
as well.

>> +  for dir in $cpu_pmu_dir
>> +  do
>> +    if [ ! -e "$dir$br_cntr_file" ]
>> +    then
>> +      echo "Not support branch counter feature [Skipped]"
> 
> Perhaps here it'd be clearer to output:
> echo "branch counter feature not supported on all core PMUs ($dir) [Skipped]"
> 

Sure, I will change it in V2.

Thanks,
Kan

> Thanks,
> Ian
> 
>> +      return
>> +    fi
>> +  done
>> +  if ! perf record -o "${perfdata}" -j any,counter ${testprog} 2> /dev/null
>> +  then
>> +    echo "Basic branch counter test [Failed record]"
>> +    err=1
>> +    return
>> +  fi
>> +  if ! perf report -i "${perfdata}" -D -q | grep -q "$br_cntr_output"
>> +  then
>> +    echo "Basic branch record test [Failed missing output]"
>> +    err=1
>> +    return
>> +  fi
>> +  echo "Basic branch counter test [Success]"
>> +}
>> +
>>  test_per_thread
>>  test_register_capture
>>  test_system_wide
>>  test_workload
>> +test_branch_counter
>>
>>  cleanup
>>  exit $err
>> --
>> 2.35.1
>>
>