Re: [PATCH] perf tests: Add auto counter reload (ACR) sampling test

["Mi, Dapeng" <dapeng1.mi@linux.intel.com>]

On 4/13/2026 9:30 AM, Ian Rogers wrote:
> On Sun, Apr 12, 2026 at 6:14 PM Dapeng Mi <dapeng1.mi@linux.intel.com> wrote:
>> Add auto counter reload sampling test to verify that the intended event
>> records can be captured and the self-reloaded events won't generate any
>> records.
>>
>> Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
>> ---
>>  tools/perf/tests/shell/record.sh | 42 ++++++++++++++++++++++++++++++++
>>  1 file changed, 42 insertions(+)
>>
>> diff --git a/tools/perf/tests/shell/record.sh b/tools/perf/tests/shell/record.sh
>> index 7cb81cf3444a..1068843282f5 100755
>> --- a/tools/perf/tests/shell/record.sh
>> +++ b/tools/perf/tests/shell/record.sh
>> @@ -402,6 +402,47 @@ test_callgraph() {
>>    echo "Callgraph test [Success]"
>>  }
>>
>> +test_acr_sampling() {
>> +  events="{instructions/period=20000,acr_mask=0x2/u,cycles/period=40000,acr_mask=0x3/u}"
>> +  pebs_events="{instructions/period=20000,acr_mask=0x2/pu,cycles/period=40000,acr_mask=0x3/u}"
>> +  echo "Auto counter reload sampling test"
>> +  if ! perf record -o "${perfdata}" -e "${events}" ${testprog} 2> /dev/null
>> +  then
>> +    echo "Auto counter reload sampling [Skipped not supported]"
>> +    return
>> +  fi
>> +  if ! perf script -i "${perfdata}" | grep -q "period=20000,acr_mask=0x2"
>> +  then
>> +    echo "Auto counter reload sampling [Failed missing instructions event]"
>> +    err=1
>> +    return
>> +  fi
>> +  if perf script -i "${perfdata}" | grep -q "period=40000,acr_mask=0x3"
>> +  then
>> +    echo "Auto counter reload sampling [Failed cycles event shouldn't be sampled]"
>> +    err=1
>> +    return
>> +  fi
>> +  if ! perf record -o "${perfdata}" -e "${pebs_events}" ${testprog} 2> /dev/null
>> +  then
>> +    echo "Auto counter reload PEBS sampling [Skipped not supported]"
>> +    return
>> +  fi
>> +  if ! perf script -i "${perfdata}" | grep -q "period=20000,acr_mask=0x2"
>> +  then
>> +    echo "Auto counter reload PEBS sampling [Failed missing instructions event]"
>> +    err=1
>> +    return
>> +  fi
>> +  if perf script -i "${perfdata}" | grep -q "period=40000,acr_mask=0x3"
>> +  then
>> +    echo "Auto counter reload PEBS sampling [Failed cycles event shouldn't be sampled]"
>> +    err=1
>> +    return
>> +  fi
>> +  echo "Auto counter reload sampling [Success]"
> Thanks Dapeng! Could we also test ratio-to-prev as well as just the
> plain acr_mask?

Good idea. Sure.


>
> Thanks,
> Ian
>
>> +}
>> +
>>  test_ratio_to_prev() {
>>    echo "ratio-to-prev test"
>>    if ! perf record -o /dev/null -e "{instructions, cycles/period=100000,ratio-to-prev=0.5/}" \
>> @@ -457,6 +498,7 @@ test_leader_sampling
>>  test_topdown_leader_sampling
>>  test_precise_max
>>  test_callgraph
>> +test_acr_sampling
>>  test_ratio_to_prev
>>
>>  # restore the default value
>>
>> base-commit: 4e03d6494f9504f8af46ba68a2a8b6877c196789
>> --
>> 2.34.1
>>