Re: [igt-dev] [PATCH v3 11/24] drm-uapi/xe: Replace useless 'instance' per unique gt_id

[Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>]

On 27/09/2023 17:53, Rodrigo Vivi wrote:
> On Tue, Sep 26, 2023 at 05:47:22PM +0100, Tvrtko Ursulin wrote:
>>
>> On 26/09/2023 14:00, Francois Dugast wrote:
>>> From: Rodrigo Vivi <rodrigo.vivi@intel.com>
>>>
>>> Align with commit ("drm/xe/uapi: Replace useless 'instance' per unique gt_id")
>>>
>>> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
>>> Signed-off-by: Francois Dugast <francois.dugast@intel.com>
>>> ---
>>>    include/drm-uapi/xe_drm.h | 65 ++++++++++++++++++++++++++-------------
>>>    tests/intel/xe_query.c    |  2 +-
>>>    2 files changed, 44 insertions(+), 23 deletions(-)
>>>
>>> diff --git a/include/drm-uapi/xe_drm.h b/include/drm-uapi/xe_drm.h
>>> index 13c693393..68cc5e051 100644
>>> --- a/include/drm-uapi/xe_drm.h
>>> +++ b/include/drm-uapi/xe_drm.h
>>> @@ -337,6 +337,47 @@ struct drm_xe_query_config {
>>>    	__u64 info[];
>>>    };
>>> +/**
>>> + * struct drm_xe_query_gt - describe an individual GT.
>>> + *
>>> + * To be used with drm_xe_query_gts, which will return a list with all the
>>> + * existing GT individual descriptions.
>>> + * Graphics Technology (GT) is a subset of a GPU/tile that is responsible for
>>> + * implementing graphics and/or media operations.
>>> + */
>>> +struct drm_xe_query_gt {
>>> +#define XE_QUERY_GT_TYPE_MAIN		0
>>> +#define XE_QUERY_GT_TYPE_REMOTE		1
>>> +#define XE_QUERY_GT_TYPE_MEDIA		2
>>> +	/** @type: GT type: Main, Remote, or Media */
>>> +	__u16 type;
>>> +	/** @gt_id: Unique ID of this GT within the PCI Device */
>>> +	__u16 gt_id;
>>> +	/** @clock_freq: A clock frequency for timestamp */
>>> +	__u32 clock_freq;
>>> +	/** @features: Reserved for future information about GT features */
>>> +	__u64 features;
>>> +	/**
>>> +	 * @native_mem_regions: Bit mask of instances from
>>> +	 * drm_xe_query_mem_usage that lives on the same GPU/Tile and have
>>> +	 * direct access.
>>> +	 */
>>> +	__u64 native_mem_regions;
>>
>> s/native/local/ ?
>>
>> Although what was wrong with distance query? It was more future proof (can't
>> ever end up with fast, slow, slower, .. ) and avoids a bit of a vague
>> non-technical names like "slow".
>>
>>> +	/**
>>> +	 * @slow_mem_regions: Bit mask of instances from
>>> +	 * drm_xe_query_mem_usage that this GT can indirectly access, although
>>> +	 * they live on a different GPU/Tile.
>>> +	 */
>>> +	__u64 slow_mem_regions;
>>> +	/**
>>> +	 * @inaccessible_mem_regions: Bit mask of instances from
>>> +	 * drm_xe_query_mem_usage that is not accessible by this GT at all.
>>> +	 */
>>> +	__u64 inaccessible_mem_regions;
>>
>> Equal to ~(native | slow) so redundant?
>>
>> Btw drm_xe_query_mem_usage is just a list of regions, nothing about usage
>> like memory usage?
> 
> I agree with all your comments here. The way xe is currently handling
> memory regions and mixing gt in the middle is strange and I'm going to
> scrutinize and change that on a follow up.
> 
> This patch here now is just to change the name to the gt_id and this
> IGT change ended up picking together the movement of the gt struct
> out of the list struct definition.
> 
> So, basically the only relevant portion of this patch is s/instance/gt_id.
> Everything else should be a follow-up work.

Ah okay. I was asked to review the gem_wsim adaptation for xe so went 
looking for xe uapi. My bad looking at the wrong place. And from what 
you say I guess I can freely hold of looking into details until the uapi 
settles down.

Regards,

Tvrtko

> 
>>
>> Regards,
>>
>> Tvrtko
>>
>>> +	/** @reserved: Reserved */
>>> +	__u64 reserved[8];
>>> +};
>>> +
>>>    /**
>>>     * struct drm_xe_query_gts - describe GTs
>>>     *
>>> @@ -347,30 +388,10 @@ struct drm_xe_query_config {
>>>    struct drm_xe_query_gts {
>>>    	/** @num_gt: number of GTs returned in gts */
>>>    	__u32 num_gt;
>>> -
>>>    	/** @pad: MBZ */
>>>    	__u32 pad;
>>> -
>>> -	/**
>>> -	 * @gts: The GTs returned for this device
>>> -	 *
>>> -	 * TODO: convert drm_xe_query_gt to proper kernel-doc.
>>> -	 * TODO: Perhaps info about every mem region relative to this GT? e.g.
>>> -	 * bandwidth between this GT and remote region?
>>> -	 */
>>> -	struct drm_xe_query_gt {
>>> -#define XE_QUERY_GT_TYPE_MAIN		0
>>> -#define XE_QUERY_GT_TYPE_REMOTE		1
>>> -#define XE_QUERY_GT_TYPE_MEDIA		2
>>> -		__u16 type;
>>> -		__u16 instance;
>>> -		__u32 clock_freq;
>>> -		__u64 features;
>>> -		__u64 native_mem_regions;	/* bit mask of instances from drm_xe_query_mem_usage */
>>> -		__u64 slow_mem_regions;		/* bit mask of instances from drm_xe_query_mem_usage */
>>> -		__u64 inaccessible_mem_regions;	/* bit mask of instances from drm_xe_query_mem_usage */
>>> -		__u64 reserved[8];
>>> -	} gts[];
>>> +	/** @gts: The GT list returned for this device */
>>> +	struct drm_xe_query_gt gts[];
>>>    };
>>>    /**
>>> diff --git a/tests/intel/xe_query.c b/tests/intel/xe_query.c
>>> index acf069f46..eb8d52897 100644
>>> --- a/tests/intel/xe_query.c
>>> +++ b/tests/intel/xe_query.c
>>> @@ -279,7 +279,7 @@ test_query_gts(int fd)
>>>    	for (i = 0; i < gts->num_gt; i++) {
>>>    		igt_info("type: %d\n", gts->gts[i].type);
>>> -		igt_info("instance: %d\n", gts->gts[i].instance);
>>> +		igt_info("gt_id: %d\n", gts->gts[i].gt_id);
>>>    		igt_info("clock_freq: %u\n", gts->gts[i].clock_freq);
>>>    		igt_info("features: 0x%016llx\n", gts->gts[i].features);
>>>    		igt_info("native_mem_regions: 0x%016llx\n",