[PATCH 2/4] perf vendor events arm64: AmpereOne: Mark affected STALL_* events impacted by errata

Ilkka Koskinen ilkka at os.amperecomputing.com
Fri Aug 4 12:40:02 PDT 2023



On Fri, 4 Aug 2023, John Garry wrote:

> On 03/08/2023 22:13, Ilkka Koskinen wrote:
>> Per errata AC03_CPU_29, STALL_SLOT_FRONTEND, STALL_FRONTEND, and STALL
>> events are not counting as expected. The follow up metrics patch will
>> include correct way to calculate the impacted events.
>> 
>> Signed-off-by: Ilkka Koskinen <ilkka at os.amperecomputing.com>
>
> Reviewed-by: John Garry <john.g.garry at oracle.com>
>
>> ---
>>   .../arch/arm64/ampere/ampereone/pipeline.json        | 12 +++++++++---
>>   1 file changed, 9 insertions(+), 3 deletions(-)
>> 
>> diff --git 
>> a/tools/perf/pmu-events/arch/arm64/ampere/ampereone/pipeline.json 
>> b/tools/perf/pmu-events/arch/arm64/ampere/ampereone/pipeline.json
>> index f9fae15f7555..711028377f3e 100644
>> --- a/tools/perf/pmu-events/arch/arm64/ampere/ampereone/pipeline.json
>> +++ b/tools/perf/pmu-events/arch/arm64/ampere/ampereone/pipeline.json
>> @@ -1,18 +1,24 @@
>>   [
>>       {
>> -        "ArchStdEvent": "STALL_FRONTEND"
>> +        "ArchStdEvent": "STALL_FRONTEND",
>> +        "Errata": "Errata AC03_CPU_29",
>> +        "BriefDescription": "Impacted by errata, use metrics instead -"
>
> why end with a '-'?

That's a great question! I wish, I remembered why I did that. Looking at 
other events with Errata field, they use '.'. I can fix those and submit 
the patchset again.

Cheers, Ilkka

>
>>       },
>>       {
>>           "ArchStdEvent": "STALL_BACKEND"
>>       },
>>       {
>> -        "ArchStdEvent": "STALL"
>> +        "ArchStdEvent": "STALL",
>> +        "Errata": "Errata AC03_CPU_29",
>> +        "BriefDescription": "Impacted by errata, use metrics instead -"
>>       },
>>       {
>>           "ArchStdEvent": "STALL_SLOT_BACKEND"
>>       },
>>       {
>> -        "ArchStdEvent": "STALL_SLOT_FRONTEND"
>> +        "ArchStdEvent": "STALL_SLOT_FRONTEND",
>> +        "Errata": "Errata AC03_CPU_29",
>> +        "BriefDescription": "Impacted by errata, use metrics instead -"
>>       },
>>       {
>>           "ArchStdEvent": "STALL_SLOT"
>
>



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