[PATCH 1/3] lib/intel_compute: loop_kernel_duration in Pipeline

[Zbigniew Kempczyński]

On Thu, Aug 14, 2025 at 03:58:12PM +0000, nishit.sharma at intel.com wrote:
> From: Nishit Sharma <nishit.sharma at intel.com>
> 
> To execute KERNEL in GPU for specific duration a brief sleep is
> required. New variable loop_kernel_duration is introduced in
> struct user_execenv which holds duration for sleep and during this
> duration the GPU will be running kernel.
> loop_kernel_duration is checked for all pipelines.

There's missing part from the 2/3 patch here.

You should explain what's for is loop kernel duration and why you've
selected sleep to control execution time of this loop kernel. You
should also explain why only single pipeline supports this method
of controlling execution time.

Code looks correct imo (apart of missing 2/3 part), but let's wait for CI.

--
Zbigniew

> 
> Signed-off-by: Nishit Sharma <nishit.sharma at intel.com>
> ---
>  lib/intel_compute.c | 21 ++++++++++++++++++++-
>  lib/intel_compute.h |  2 ++
>  2 files changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/intel_compute.c b/lib/intel_compute.c
> index 147dd2916..125331c53 100644
> --- a/lib/intel_compute.c
> +++ b/lib/intel_compute.c
> @@ -849,6 +849,9 @@ static void compute_exec(int fd, const unsigned char *kernel,
>  	uint16_t devid = intel_get_drm_devid(fd);
>  	int entries = ARRAY_SIZE(bo_dict);
>  
> +	if (user && (user->kernel || user->loop_kernel_duration))
> +		igt_skip("Pipeline doesn't support loop_kernel\n");
> +
>  	bo_execenv_create(fd, &execenv, eci, user);
>  
>  	/* Set dynamic sizes */
> @@ -1131,6 +1134,9 @@ static void xehp_compute_exec(int fd, const unsigned char *kernel,
>  	uint64_t bind_output_addr = (user && user->output_addr) ? user->output_addr : ADDR_OUTPUT;
>  	int entries = ARRAY_SIZE(bo_dict);
>  
> +	if (user && (user->kernel || user->loop_kernel_duration))
> +		igt_skip("Pipeline doesn't support loop_kernel\n");
> +
>  	bo_execenv_create(fd, &execenv, eci, user);
>  
>  	/* Set dynamic sizes */
> @@ -1343,6 +1349,9 @@ static void xehpc_compute_exec(int fd, const unsigned char *kernel,
>  	uint64_t bind_output_addr = (user && user->output_addr) ? user->output_addr : ADDR_OUTPUT;
>  	int entries = ARRAY_SIZE(bo_dict);
>  
> +	if (user && (user->kernel || user->loop_kernel_duration))
> +		igt_skip("Pipeline doesn't support loop_kernel\n");
> +
>  	bo_execenv_create(fd, &execenv, eci, user);
>  
>  	/* Set dynamic sizes */
> @@ -1731,6 +1740,9 @@ static void xelpg_compute_exec(int fd, const unsigned char *kernel,
>  	uint64_t bind_output_addr = (user && user->output_addr) ? user->output_addr : ADDR_OUTPUT;
>  	int entries = ARRAY_SIZE(bo_dict);
>  
> +	if (user && (user->kernel || user->loop_kernel_duration))
> +		igt_skip("Pipeline doesn't support loop_kernel\n");
> +
>  	bo_execenv_create(fd, &execenv, eci, user);
>  
>  	/* Set dynamic sizes */
> @@ -1849,7 +1861,14 @@ static void xe2lpg_compute_exec(int fd, const unsigned char *kernel,
>  				    OFFSET_KERNEL, 0, false,
>  				    execenv.array_size);
>  
> -	bo_execenv_exec(&execenv, ADDR_BATCH);
> +	if (user && user->loop_kernel_duration) {
> +		bo_execenv_exec_async(&execenv, ADDR_BATCH);
> +		igt_measured_usleep(user->loop_kernel_duration);
> +		((int *)bo_dict[4].data)[0] = MAGIC_LOOP_STOP;
> +		bo_execenv_sync(&execenv);
> +		user->skip_results_check = 1;
> +	} else
> +		bo_execenv_exec(&execenv, ADDR_BATCH);
>  
>  	if (!user || (user && !user->skip_results_check))
>  		bo_check_square(input_data, output_data, execenv.array_size);
> diff --git a/lib/intel_compute.h b/lib/intel_compute.h
> index 412791d07..54a1c7f82 100644
> --- a/lib/intel_compute.h
> +++ b/lib/intel_compute.h
> @@ -63,6 +63,8 @@ struct user_execenv {
>  	uint64_t input_addr;
>  	/** @output_addr: override default address of the output array if provided */
>  	uint64_t output_addr;
> +	/** @loop_kernel_duration: duration till kernel should execute in gpu **/
> +	uint64_t loop_kernel_duration;
>  };
>  
>  enum execenv_alloc_prefs {
> -- 
> 2.43.0
>