Re: [PATCH v4 3/8] drm/xe/uapi: Add configs for Engine busyness

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

Hi Aravind

On 1/3/2024 10:56 AM, Aravind Iddamsetty wrote:
> 
> On 12/22/23 13:15, Riana Tauro wrote:
>> GuC provides engine busyness ticks as a 64 bit counter which count
>> as clock ticks.
>>
>> Add configs to the uapi to expose Engine busyness via PMU.
>>
>> v2: add "__" prefix for internal helpers
>>      add a simple helper for application usage (Aravind)
>>
>> v3: rebase
>>      change internal uapi pmu config helpers (Umesh)
>>
>> Cc: Aravind Iddamsetty <aravind.iddamsetty@linux.intel.com>
>> Signed-off-by: Riana Tauro <riana.tauro@intel.com>
>> ---
>>   include/uapi/drm/xe_drm.h | 41 +++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 41 insertions(+)
>>
>> diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
>> index 9fa3ae324731..f8456cda5cda 100644
>> --- a/include/uapi/drm/xe_drm.h
>> +++ b/include/uapi/drm/xe_drm.h
>> @@ -1340,6 +1340,47 @@ struct drm_xe_wait_user_fence {
>>   	__u64 reserved[2];
>>   };
>>   
>> +/**
>> + * DOC: XE PMU event config IDs
>> + *
>> + * Check 'man perf_event_open' to use the ID's DRM_XE_PMU_XXXX listed in xe_drm.h
>> + * in 'struct perf_event_attr' as part of perf_event_open syscall to read a
>> + * particular event.
>> + *
>> + */
>> +
>> +/**
>> + * enum drm_xe_pmu_engine_sample - Supported PMU engine samples
>> + */
>> +enum drm_xe_pmu_engine_sample {
>> +	/** @DRM_XE_PMU_SAMPLE_BUSY_TICKS: Engine busy ticks */
>> +	DRM_XE_PMU_SAMPLE_BUSY_TICKS = 0,
>> +};
>> +
>> +/*
>> + * Top bits of every counter are GT id.
>> + */
>> +#define __DRM_XE_PMU_GT_SHIFT (56)
>> +#define __DRM_XE_PMU_SAMPLE_BITS (4)
>> +#define __DRM_XE_PMU_SAMPLE_INSTANCE_BITS (8)
>> +#define __DRM_XE_PMU_CLASS_SHIFT \
>> +	(__DRM_XE_PMU_SAMPLE_BITS + __DRM_XE_PMU_SAMPLE_INSTANCE_BITS)
>> +
>> +#define __DRM_XE_PMU_GT_EVENT(gt, x) \
>> +	(((__u64)(x)) | ((__u64)(gt) << __DRM_XE_PMU_GT_SHIFT))
>> +
>> +#define __DRM_XE_PMU_ENGINE(class, instance, sample) \
>> +	(((class) << __DRM_XE_PMU_CLASS_SHIFT | \
>> +	(instance) << __DRM_XE_PMU_SAMPLE_BITS | \
>> +	(sample)))
>> +
>> +#define __DRM_XE_PMU_OTHER(gt, x) \
>> +	(__DRM_XE_PMU_GT_EVENT(gt, 0xfffff) + 1 + (x))
> Use __DRM_XE_PMU_ENGINE(0xff, 0xff, 0xf) instead of 0xfffff so that it will be clear
> that it is starting after the engine event.
Previous comments from Umesh suggested to use 0xfffff so changed it from 
rev3.
> 
> But __DRM_XE_PMU_OTHER is not used any where so why to introduce in this patch.
I added it here so that it can be used in the next patch to check if its 
engine event.

Will move total active ticks config also to the same patch so that all 
configs are in one patch.

Thanks
Riana


> 
> Thanks,
> Aravind.
>> +
>> +#define DRM_XE_PMU_ENGINE_BUSY_TICKS(gt, class, instance) \
>> +	__DRM_XE_PMU_GT_EVENT(gt, __DRM_XE_PMU_ENGINE(class, instance, \
>> +						      DRM_XE_PMU_SAMPLE_BUSY_TICKS))
>> +
>>   #if defined(__cplusplus)
>>   }
>>   #endif