[PATCH 3/3] tests/intel/xe_exec_system_allocator: Rebind the prefetch ranges

[Cavitt, Jonathan]

-----Original Message-----
From: igt-dev <igt-dev-bounces at lists.freedesktop.org> On Behalf Of sai.gowtham.ch at intel.com
Sent: Tuesday, May 13, 2025 10:07 AM
To: igt-dev at lists.freedesktop.org; Ch, Sai Gowtham <sai.gowtham.ch at intel.com>; Ghimiray, Himal Prasad <himal.prasad.ghimiray at intel.com>; Brost, Matthew <matthew.brost at intel.com>
Subject: [PATCH 3/3] tests/intel/xe_exec_system_allocator: Rebind the prefetch ranges
> 
> From: Sai Gowtham Ch <sai.gowtham.ch at intel.com>
> 
> Test rebinds the prefetch ranges to check the ideal behaviour of prefetch mechanisim,

s/mechanism/mechanism

> expecting address ranges in the corresponding mem regions has to be created again and
> use those address ranges to submit workloads.
> 
> Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray at intel.com>
> Cc: Matthew Brost <matthew.brost at intel.com>
> Signed-off-by: Sai Gowtham Ch <sai.gowtham.ch at intel.com>
> ---
>  tests/intel/xe_exec_system_allocator.c | 47 +++++++++++++++++++++++---
>  1 file changed, 42 insertions(+), 5 deletions(-)
> 
> diff --git a/tests/intel/xe_exec_system_allocator.c b/tests/intel/xe_exec_system_allocator.c
> index c3f0e61f3..94907847c 100644
> --- a/tests/intel/xe_exec_system_allocator.c
> +++ b/tests/intel/xe_exec_system_allocator.c
> @@ -484,6 +484,24 @@ static void test_basic(int fd, struct drm_xe_engine_class_instance *eci,
>   * Description: Prefetch of mutliple ranges within arg[1] size and check if multiple ranges are created
>   * Test category: functionality test
>   *
> + * SUBTEST: bind-vram-%s
> + * Description: Validate prefetch-smem of size arg[1] by rebinding them with prefetch-vram to
> + * 		check the behaviour, ideal behaviour is to migrate ranges
> + * Test category: functionality test
> + *
> + * SUBTEST: bind-smem-%s
> + * Description: Validate prefetch-smem of size arg[1] by rebinding them with prefetch-vram
> + * 		check the behaviour, ideal behaviour is to migrate ranges
> + * Test category: functionality test
> + *
> + * SUBTEST: multi-range-bind-vram-%s
> + * Description: Validate multiple ranges of size arg[1] by binding them with multiple ranges at vram
> + * Test category: functionality test
> + *
> + * SUBTEST: multi-range-bind-smem-%s
> + * Description: Validate multiple ranges of size arg[1] by binding them with multiple ranges at smem
> + * Test category: functionality test
> + *
>   * arg[1]:
>   *
>   * @SZ_4K: SZ_4K
> @@ -492,7 +510,7 @@ static void test_basic(int fd, struct drm_xe_engine_class_instance *eci,
>   */
>  #define MAX_BATCH_DWORDS 16
>  static void prefetch(int fd, struct drm_xe_engine_class_instance *eci,
> -		     size_t bo_size, unsigned int flags, int num_dwords)
> +		     size_t bo_size, unsigned int flags, int num_dwords, bool bind)

Rather than adding bind as a boolean flag here, maybe we should add a new flag that
performs the same job?  Since we're borrowing the many_alloc flags section anyways, it
could maybe be:

"""
#define VRAM		(0x1 << 5)
#define BIND		(0x1 << 6)
"""

Then, below, instead of checking for the boolean value, we check if "flag & BIND".

Combine this with the advice I gave for the previous patch, and your mode array
would looks something like:

"""
	const struct mode {
		const char *name;
		unsigned int flags;
		size_t size;
	} mode[] = {
		{"smem-SZ_4K", 0, SZ_4K},
		{"smem-SZ_64K", 0, SZ_64K},
		{"smem-SZ_2M", 0, SZ_2M},
		{"vram-SZ_4K", VRAM, SZ_4K},
		{"vram-SZ_64K", VRAM, SZ_64K},
		{"vram-SZ_2M", VRAM, SZ_2M},
		{"bind-smem-SZ_4K", BIND, SZ_4K},
		{"bind-smem-SZ_64K", BIND, SZ_64K},
		{"bind-smem-SZ_2M", BIND, SZ_2M},
		{"bind-vram-SZ_4K", VRAM | BIND, SZ_4K},
		{"bind-vram-SZ_64K", VRAM | BIND, SZ_64K},
		{"bind-vram-SZ_2M", VRAM | BIND, SZ_2M},
		{ NULL },
	};
"""
The nice thing about this approach is that it doesn't necessitate changing the
below list of subtests in the "for each mode" loop, as long as you don't mind
changing the name of the bind subtests from "bind-.*" to "prefetch-bind-.*".
-Jonathan Cavitt

>  {
>  	struct batch_data *data;
>  	uint64_t target_addr;
> @@ -542,6 +560,13 @@ static void prefetch(int fd, struct drm_xe_engine_class_instance *eci,
>  	sync[0].addr = to_user_pointer(exec_ufence);
>  	xe_vm_prefetch_async(fd, vm, 0, 0, addr, bo_size, sync, 1, flags & VRAM ? 1 : 0);
>  	xe_wait_ufence(fd, exec_ufence, USER_FENCE_VALUE, 0, NSEC_PER_SEC);
> +	if (bind) {
> +		exec_ufence[0] = 0;
> +		sync[0].addr = to_user_pointer(exec_ufence);
> +		xe_vm_prefetch_async(fd, vm, 0, 0, addr, bo_size, sync, 1, flags & VRAM ? 0 : 1);
> +		xe_wait_ufence(fd, exec_ufence, USER_FENCE_VALUE, 0, NSEC_PER_SEC);
> +		exec_ufence[0] = 0;
> +	}
>  	exec.exec_queue_id = exec_queues;
>  
>  	for (int i = 0; i < num_dwords; i++) {
> @@ -2045,16 +2070,28 @@ igt_main
>  
>  	for (m = mode; m->name; m++) {
>		  igt_subtest_f("prefetch-smem-%s", m->name)
> -		        prefetch(fd, &engine->instance, m->size, 0, 1);
> +		        prefetch(fd, &engine->instance, m->size, 0, 1, 0);
>  
>		  igt_subtest_f("prefetch-vram-%s", m->name)
> -		        prefetch(fd, &engine->instance, m->size, VRAM, 1);
> +		        prefetch(fd, &engine->instance, m->size, VRAM, 1, 0);
>  
>		  igt_subtest_f("multi-range-smem-%s", m->name)
> -		        prefetch(fd, &engine->instance, m->size, 0, 10);
> +		        prefetch(fd, &engine->instance, m->size, 0, 10, 0);
>  
>		  igt_subtest_f("multi-range-vram-%s", m->name)
> -		        prefetch(fd, &engine->instance, m->size, VRAM, 10);
> +		        prefetch(fd, &engine->instance, m->size, VRAM, 10, 0);
> +
> +		igt_subtest_f("bind-vram-%s", m->name)
> +			prefetch(fd, &engine->instance, m->size, 0, 1, 1);
> +
> +		igt_subtest_f("bind-smem-%s", m->name)
> +			prefetch(fd, &engine->instance, m->size, VRAM, 1, 1);
> +
> +		igt_subtest_f("multi-range-bind-vram-%s", m->name)
> +			prefetch(fd, &engine->instance, m->size, 0, 10, 1);
> +
> +		igt_subtest_f("multi-range-bind-smem-%s", m->name)
> +			prefetch(fd, &engine->instance, m->size, VRAM, 10, 1);
>          }
>  
>  	igt_fixture {
> -- 
> 2.34.1
> 
>