Re: [PATCH] perf arm-spe: Add support for SPE Data Source packet on AmpereOne

[Ilkka Koskinen <ilkka@os.amperecomputing.com>]

Hi James,

On Fri, 25 Oct 2024, James Clark wrote:
> On 25/10/2024 12:30 am, Ilkka Koskinen wrote:
>> Decode SPE Data Source packets on AmpereOne. The field is IMPDEF.
>> 
>> Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
>> ---
>>   .../util/arm-spe-decoder/arm-spe-decoder.h    |  9 +++
>>   tools/perf/util/arm-spe.c                     | 61 +++++++++++++++++++
>>   2 files changed, 70 insertions(+)
>> 
>> diff --git a/tools/perf/util/arm-spe-decoder/arm-spe-decoder.h 
>> b/tools/perf/util/arm-spe-decoder/arm-spe-decoder.h
>> index 1443c28545a9..e4115b1e92b2 100644
>> --- a/tools/perf/util/arm-spe-decoder/arm-spe-decoder.h
>> +++ b/tools/perf/util/arm-spe-decoder/arm-spe-decoder.h
>> @@ -67,6 +67,15 @@ enum arm_spe_neoverse_data_source {
>>   	ARM_SPE_NV_DRAM		 = 0xe,
>>   };
>>   +enum arm_spe_ampereone_data_source {
>> +	ARM_SPE_AMPEREONE_LOCAL_CHIP_CACHE_OR_DEVICE	= 0x0,
>> +	ARM_SPE_AMPEREONE_SLC				= 0x3,
>> +	ARM_SPE_AMPEREONE_REMOTE_CHIP_CACHE		= 0x5,
>> +	ARM_SPE_AMPEREONE_DDR				= 0x7,
>> +	ARM_SPE_AMPEREONE_L1D				= 0x8,
>> +	ARM_SPE_AMPEREONE_L2D				= 0x9,
>> +};
>> +
>>   struct arm_spe_record {
>>   	enum arm_spe_sample_type type;
>>   	int err;
>> diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c
>> index 138ffc71b32d..04bd21ad7ea8 100644
>> --- a/tools/perf/util/arm-spe.c
>> +++ b/tools/perf/util/arm-spe.c
>> @@ -515,10 +515,69 @@ static void arm_spe__synth_data_source_generic(const 
>> struct arm_spe_record *reco
>>   		data_src->mem_lvl |= PERF_MEM_LVL_REM_CCE1;
>>   }
>>   +static const struct midr_range ampereone_source_spe[] = {
>> +	MIDR_ALL_VERSIONS(MIDR_AMPERE1A),
>> +	{},
>> +};
>> +
>> +static void arm_spe__synth_data_source_ampereone(const struct 
>> arm_spe_record *record,
>> +						 union perf_mem_data_src 
>> *data_src,
>> +						 u64 midr)
>> +{
>> +	if (!is_midr_in_range_list(midr, ampereone_source_spe)) {
>> +		arm_spe__synth_data_source_generic(record, data_src);
>> +		return;
>> +	}
> [...]
>>   static u64 arm_spe__synth_data_source(const struct arm_spe_record 
>> *record, u64 midr)
>>   {
>>   	union perf_mem_data_src	data_src = { .mem_op = PERF_MEM_OP_NA };
>>   	bool is_neoverse = is_midr_in_range_list(midr, neoverse_spe);
>> +	bool is_ampereone = (read_cpuid_implementor() == ARM_CPU_IMP_AMPERE);
>> 
>
> Hi Ilkka,
>
> I think this read_cpuid_implementor() is for the device that's running 
> report, rather than record. You need to use the midr that's saved into the 
> file.

Uh, that didn't come to my mind at all.

> But it looks like you've done that for is_midr_in_range_list(midr, 
> ampereone_source_spe) above. Is it possible to just do that and not 
> read_cpuid_implementor() and then it's done the same way as neoverse and also 
> works off target?

You're right, it's wrong and there's no even need for separate implementor 
id check. I fix it.

Cheers, Ilkka

>
> Thanks
>
> James
>
>