Re: [PATCH v2 8/8] drm/xe/pmu: Add PMU support for engine busyness

[Riana Tauro <riana.tauro@intel.com>]

On 12/18/2024 8:21 PM, Riana Tauro wrote:
> 
> 
> On 12/18/2024 7:43 PM, Lucas De Marchi wrote:
>> On Wed, Dec 18, 2024 at 10:42:53AM +0530, Riana Tauro wrote:
>>> Hi Lucas
>>>
>>> On 12/13/2024 11:28 AM, Lucas De Marchi wrote:
>>>> On Thu, Nov 21, 2024 at 12:09:04PM +0530, Riana Tauro wrote:
>>>>> PMU provides two counters (<engine>-busy-ticks-gt<n>,
>>>>> <engine>-total-ticks-gt<n>) to calculate engine busyness. When 
>>>>> querying
>>>>> engine busyness, user must group these 2 counters using the perf_event
>>>>> group mechanism to ensure both counters are sampled together.
>>>>>
>>>>> To list engine busyness counters use the following
>>>>>
>>>>> ./perf list
>>>>>  xe_0000_03_00.0/bcs0-busy-ticks-gt0/               [Kernel PMU event]
>>>>
>>>> this will need a rebase on latest versions of the pmu patches as we
>>>> moved to have gt as a param rather than mangling the event name.
>>>
>>> In case of multiple gts, there might be different engines for each gt
>>> So should we display a common name and unsupported in case the engine 
>>> does not belong to the gt?
>>>
>>> sudo ./perf stat -e xe_0000_00_02.0/vcs0-busy-ticks,gt_id=0/ -I 1000
>>
>> why is engine not a param, like gt?
Wouldn't it be better to have engine name in the event name? Otherwise 
anyone using perf tool needs to find the engine class to name mapping

@Umesh any inputs here?
> are you suggesting to have both engine and instance too as parameters?
> Something like this?
> 
> xe_0000_00_02.0/busy-ticks,engine_class=1,engine_instance=0,gt_id=0/
> 
> 
>>
>> Lucas De Marchi
>