Re: [PATCH i-g-t v2] tests/xe_create: Use separate VMs per process

["Welty, Brian" <brian.welty@intel.com>]

On 12/21/2023 12:44 PM, Cavitt, Jonathan wrote:
> We currently exercise cross-user impact in xe_create by attempting to
> concurrently create a large number of exec queues on a single vm using
> forked child processes.  This is unrealistic, as multiple users are more
> likely to be using separate file descriptors for creating exec queues.
> 
> Update the test to reflect this use case.
> 
> v2:
> - Keep the original test path (which uses a single shared vm across
> multiple forked processes) intact, using a flag to denote which path to
> take.
> - Increase the MAXTIME in the shared vm case.
> 
> Suggested-by: Brian Welty <brian.welty@intel.com>
> Signed-off-by: Jonathan Cavitt <jonathan.cavitt@intel.com>


LGTM.  Thanks Jonathan.

Reviewed-by: Brian Welty <brian.welty@intel.com>


> CC: Zbigniew Kempczynski <zbigniew.kempczynski@intel.com>
> CC: Lucas De Marchi <lucas.demarchi@intel.com>
> CC: Kamil Konieczny <kamil.konieczny@linux.intel.com>
> CC: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
> ---
>   tests/intel/xe_create.c | 50 ++++++++++++++++++++++++++++++++---------
>   1 file changed, 40 insertions(+), 10 deletions(-)
> 
> diff --git a/tests/intel/xe_create.c b/tests/intel/xe_create.c
> index 0aa32c788a..6d06708492 100644
> --- a/tests/intel/xe_create.c
> +++ b/tests/intel/xe_create.c
> @@ -150,6 +150,11 @@ enum exec_queue_destroy {
>   	LEAK
>   };
>   
> +enum vm_count {
> +	MULTI,
> +	SHARED
> +};
> +
>   #define MAXEXECQUEUES 2048
>   #define MAXTIME 5
>   
> @@ -163,16 +168,22 @@ enum exec_queue_destroy {
>    *
>    * @noleak:				destroy exec_queues in the code
>    * @leak:				destroy exec_queues in close() path
> + * @noleak-shared:			same as noleak, but with a shared vm
> + * @leak-shared:			same as leak, but with a shared vm
>    */
> -static void create_execqueues(int fd, enum exec_queue_destroy ed)
> +static void create_execqueues(int fd, enum exec_queue_destroy ed,
> +			      enum vm_count vc)
>   {
>   	struct timespec tv = { };
>   	uint32_t num_engines, exec_queues_per_process, vm;
>   	int nproc = sysconf(_SC_NPROCESSORS_ONLN), seconds;
> +	int real_timeout = MAXTIME * (vc == SHARED ? 4 : 1);
>   
> -	fd = drm_reopen_driver(fd);
> -	num_engines = xe_number_engines(fd);
> -	vm = xe_vm_create(fd, 0, 0);
> +	if (vc == SHARED) {
> +		fd = drm_reopen_driver(fd);
> +		num_engines = xe_number_engines(fd);
> +		vm = xe_vm_create(fd, 0, 0);
> +	}
>   
>   	exec_queues_per_process = max_t(uint32_t, 1, MAXEXECQUEUES / nproc);
>   	igt_debug("nproc: %u, exec_queues per process: %u\n", nproc, exec_queues_per_process);
> @@ -184,6 +195,12 @@ static void create_execqueues(int fd, enum exec_queue_destroy ed)
>   		uint32_t exec_queue, exec_queues[exec_queues_per_process];
>   		int idx, err, i;
>   
> +		if (vc == MULTI) {
> +			fd = drm_reopen_driver(fd);
> +			num_engines = xe_number_engines(fd);
> +			vm = xe_vm_create(fd, 0, 0);
> +		}
> +
>   		srandom(n);
>   
>   		for (i = 0; i < exec_queues_per_process; i++) {
> @@ -206,16 +223,23 @@ static void create_execqueues(int fd, enum exec_queue_destroy ed)
>   				xe_exec_queue_destroy(fd, exec_queues[i]);
>   			}
>   		}
> +
> +		if (vc == MULTI) {
> +			xe_vm_destroy(fd, vm);
> +			drm_close_driver(fd);
> +		}
>   	}
>   	igt_waitchildren();
>   
> -	xe_vm_destroy(fd, vm);
> -	drm_close_driver(fd);
> +	if (vc == SHARED) {
> +		xe_vm_destroy(fd, vm);
> +		drm_close_driver(fd);
> +	}
>   
>   	seconds = igt_seconds_elapsed(&tv);
> -	igt_assert_f(seconds < MAXTIME,
> +	igt_assert_f(seconds < real_timeout,
>   		     "Creating %d exec_queues tooks too long: %d [limit: %d]\n",
> -		     MAXEXECQUEUES, seconds, MAXTIME);
> +		     MAXEXECQUEUES, seconds, real_timeout);
>   }
>   
>   /**
> @@ -384,10 +408,16 @@ igt_main_args("Q:p:", NULL, help_str, opt_handler, NULL)
>   	}
>   
>   	igt_subtest("create-execqueues-noleak")
> -		create_execqueues(xe, NOLEAK);
> +		create_execqueues(xe, NOLEAK, MULTI);
>   
>   	igt_subtest("create-execqueues-leak")
> -		create_execqueues(xe, LEAK);
> +		create_execqueues(xe, LEAK, MULTI);
> +
> +	igt_subtest("create-execqueues-noleak-shared")
> +		create_execqueues(xe, NOLEAK, SHARED);
> +
> +	igt_subtest("create-execqueues-leak-shared")
> +		create_execqueues(xe, LEAK, SHARED);
>   
>   	igt_subtest("create-massive-size") {
>   		create_massive_size(xe);