Re: [igt-dev] [PATCH i-g-t 09/14] benchmarks/gem_wsim: use lib code to query engines

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

On 26/09/2023 09:44, Marcin Bernatowicz wrote:
> Use code in lib/i915/gem_engine_topology to query engines.
> 
> Signed-off-by: Marcin Bernatowicz <marcin.bernatowicz@linux.intel.com>
> ---
>   benchmarks/gem_wsim.c | 157 +++++-------------------------------------
>   1 file changed, 19 insertions(+), 138 deletions(-)
> 
> diff --git a/benchmarks/gem_wsim.c b/benchmarks/gem_wsim.c
> index 2e6eb6388..a3339e1b2 100644
> --- a/benchmarks/gem_wsim.c
> +++ b/benchmarks/gem_wsim.c
> @@ -456,150 +456,31 @@ static int str_to_engine(const char *str)
>   	return -1;
>   }
>   
> -static bool __engines_queried;
> -static unsigned int __num_engines;
> -static struct i915_engine_class_instance *__engines;
> -
> -static int
> -__i915_query(int i915, struct drm_i915_query *q)
> +static struct intel_engine_data *query_engines(void)
>   {
> -	if (igt_ioctl(i915, DRM_IOCTL_I915_QUERY, q))
> -		return -errno;
> -	return 0;
> -}
> +	static struct intel_engine_data engines = {};
>   
> -static int
> -__i915_query_items(int i915, struct drm_i915_query_item *items, uint32_t n_items)
> -{
> -	struct drm_i915_query q = {
> -		.num_items = n_items,
> -		.items_ptr = to_user_pointer(items),
> -	};
> -	return __i915_query(i915, &q);
> -}
> +	if (engines.nengines)
> +		return &engines;
>   
> -static void
> -i915_query_items(int i915, struct drm_i915_query_item *items, uint32_t n_items)
> -{
> -	igt_assert_eq(__i915_query_items(i915, items, n_items), 0);
> -}
> -
> -static bool has_engine_query(int i915)
> -{
> -	struct drm_i915_query_item item = {
> -		.query_id = DRM_I915_QUERY_ENGINE_INFO,
> -	};
> -
> -	return __i915_query_items(i915, &item, 1) == 0 && item.length > 0;
> -}
> -
> -static void query_engines(void)
> -{
> -	struct i915_engine_class_instance *engines;
> -	unsigned int num;
> -
> -	if (__engines_queried)
> -		return;
> -
> -	__engines_queried = true;
> -
> -	if (!has_engine_query(fd)) {
> -		unsigned int num_bsd = gem_has_bsd(fd) + gem_has_bsd2(fd);
> -		unsigned int i = 0;
> -
> -		igt_assert(num_bsd);
> -
> -		num = 1 + num_bsd;
> -
> -		if (gem_has_blt(fd))
> -			num++;
> -
> -		if (gem_has_vebox(fd))
> -			num++;
> -
> -		engines = calloc(num,
> -				 sizeof(struct i915_engine_class_instance));
> -		igt_assert(engines);
> -
> -		engines[i].engine_class = I915_ENGINE_CLASS_RENDER;
> -		engines[i].engine_instance = 0;
> -		i++;
> -
> -		if (gem_has_blt(fd)) {
> -			engines[i].engine_class = I915_ENGINE_CLASS_COPY;
> -			engines[i].engine_instance = 0;
> -			i++;
> -		}
> -
> -		if (gem_has_bsd(fd)) {
> -			engines[i].engine_class = I915_ENGINE_CLASS_VIDEO;
> -			engines[i].engine_instance = 0;
> -			i++;
> -		}
> -
> -		if (gem_has_bsd2(fd)) {
> -			engines[i].engine_class = I915_ENGINE_CLASS_VIDEO;
> -			engines[i].engine_instance = 1;
> -			i++;
> -		}
> -
> -		if (gem_has_vebox(fd)) {
> -			engines[i].engine_class =
> -				I915_ENGINE_CLASS_VIDEO_ENHANCE;
> -			engines[i].engine_instance = 0;
> -			i++;
> -		}
> -	} else {
> -		struct drm_i915_query_engine_info *engine_info;
> -		struct drm_i915_query_item item = {
> -			.query_id = DRM_I915_QUERY_ENGINE_INFO,
> -		};
> -		const unsigned int sz = 4096;
> -		unsigned int i;
> -
> -		engine_info = malloc(sz);
> -		igt_assert(engine_info);
> -		memset(engine_info, 0, sz);
> -
> -		item.data_ptr = to_user_pointer(engine_info);
> -		item.length = sz;
> -
> -		i915_query_items(fd, &item, 1);
> -		igt_assert(item.length > 0);
> -		igt_assert(item.length <= sz);
> -
> -		num = engine_info->num_engines;
> -
> -		engines = calloc(num,
> -				 sizeof(struct i915_engine_class_instance));
> -		igt_assert(engines);
> -
> -		for (i = 0; i < num; i++) {
> -			struct drm_i915_engine_info *engine =
> -				(struct drm_i915_engine_info *)&engine_info->engines[i];
> -
> -			engines[i] = engine->engine;
> -		}
> -	}
> -
> -	__engines = engines;
> -	__num_engines = num;
> +	engines = intel_engine_list_of_physical(fd);
> +	igt_assert(engines.nengines);
> +	return &engines;
>   }
>   
>   static unsigned int num_engines_in_class(enum intel_engine_id class)
>   {
> -	unsigned int i, count = 0;
> +	const struct intel_engine_data *engines = query_engines();
> +	unsigned int count = 0;
> +	int i;
>   
>   	igt_assert(class == VCS);
>   
> -	query_engines();
> -
> -	for (i = 0; i < __num_engines; i++) {
> -		if (__engines[i].engine_class == I915_ENGINE_CLASS_VIDEO)
> +	for (i = 0; i < engines->nengines; i++) {

nengines is uint32_t so probably best to keep i unsigned.

> +		if (engines->engines[i].class == I915_ENGINE_CLASS_VIDEO)
>   			count++;
>   	}
>   
> -	igt_assert(count);

Why dropping this?

Regards,

Tvrtko

>   	return count;
>   }
>   
> @@ -607,16 +488,15 @@ static void
>   fill_engines_id_class(enum intel_engine_id *list,
>   		      enum intel_engine_id class)
>   {
> +	const struct intel_engine_data *engines = query_engines();
>   	enum intel_engine_id engine = VCS1;
>   	unsigned int i, j = 0;
>   
>   	igt_assert(class == VCS);
>   	igt_assert(num_engines_in_class(VCS) <= 2);
>   
> -	query_engines();
> -
> -	for (i = 0; i < __num_engines; i++) {
> -		if (__engines[i].engine_class != I915_ENGINE_CLASS_VIDEO)
> +	for (i = 0; i < engines->nengines; i++) {
> +		if (engines->engines[i].class != I915_ENGINE_CLASS_VIDEO)
>   			continue;
>   
>   		list[j++] = engine++;
> @@ -626,17 +506,18 @@ fill_engines_id_class(enum intel_engine_id *list,
>   static unsigned int
>   find_physical_instance(enum intel_engine_id class, unsigned int logical)
>   {
> +	const struct intel_engine_data *engines = query_engines();
>   	unsigned int i, j = 0;
>   
>   	igt_assert(class == VCS);
>   
> -	for (i = 0; i < __num_engines; i++) {
> -		if (__engines[i].engine_class != I915_ENGINE_CLASS_VIDEO)
> +	for (i = 0; i < engines->nengines; i++) {
> +		if (engines->engines[i].class != I915_ENGINE_CLASS_VIDEO)
>   			continue;
>   
>   		/* Map logical to physical instances. */
>   		if (logical == j++)
> -			return __engines[i].engine_instance;
> +			return engines->engines[i].instance;
>   	}
>   
>   	igt_assert(0);