Re: [PATCH i-g-t 8/8] tests/intel/xe_sriov_scheduling: Add default fair scheduling test

["Laguna, Lukasz" <lukasz.laguna@intel.com>]

On 5/27/2026 22:56, Marcin Bernatowicz wrote:
> Verify PF and enabled VFs keep a fair share with the driver-applied
> default scheduling settings, without overriding scheduling parameters.
>
> Signed-off-by: Marcin Bernatowicz <marcin.bernatowicz@linux.intel.com>
> Cc: Adam Miszczak <adam.miszczak@linux.intel.com>
> Cc: Jakub Kolakowski <jakub1.kolakowski@intel.com>
> Cc: Lukasz Laguna <lukasz.laguna@intel.com>

Reviewed-by: Lukasz Laguna <lukasz.laguna@intel.com>

> ---
>   tests/intel/xe_sriov_scheduling.c | 145 ++++++++++++++++++++++++++++++
>   1 file changed, 145 insertions(+)
>
> diff --git a/tests/intel/xe_sriov_scheduling.c b/tests/intel/xe_sriov_scheduling.c
> index 915442380..aa3e5fccc 100644
> --- a/tests/intel/xe_sriov_scheduling.c
> +++ b/tests/intel/xe_sriov_scheduling.c
> @@ -1271,6 +1271,112 @@ static void nonpreempt_engine_resets(int pf_fd, int num_vfs,
>   	subm_set_fini(set);
>   }
>   
> +static struct job_sched_params
> +prepare_default_enabled_job_sched_params(int pf_fd,
> +					 const uint8_t *vf_ids,
> +					 size_t num_functions,
> +					 int job_timeout_ms)
> +{
> +	struct job_sched_params params = { };
> +	uint32_t min_exec_quantum_ms = UINT32_MAX;
> +
> +	params.sched_params = (struct vf_sched_params) {
> +		.exec_quantum_ms = xe_sriov_admin_get_exec_quantum_ms(pf_fd, vf_ids[0]),
> +		.preempt_timeout_us = xe_sriov_admin_get_preempt_timeout_us(pf_fd, vf_ids[0]),
> +		.priority = xe_sriov_admin_get_sched_priority(pf_fd, vf_ids[0], NULL),
> +	};
> +
> +	for (size_t n = 0; n < num_functions; ++n) {
> +		uint32_t exec_quantum_ms =
> +			xe_sriov_admin_get_exec_quantum_ms(pf_fd, vf_ids[n]);
> +
> +		min_exec_quantum_ms = min(min_exec_quantum_ms,
> +					  exec_quantum_ms);
> +	}
> +
> +	params.duration_ms = calculate_job_duration_ms(min_exec_quantum_ms);
> +	params.num_repeats = adjust_num_repeats(params.duration_ms, num_functions);
> +
> +	igt_require_f(params.duration_ms +
> +		      (num_functions - 1) * params.sched_params.exec_quantum_ms <=
> +		      job_timeout_ms,
> +		      "Default scheduling eq=%ums across %zu functions exceeds job timeout=%dms\n",
> +		      params.sched_params.exec_quantum_ms, num_functions, job_timeout_ms);
> +
> +	return params;
> +}
> +
> +static void validate_default_enabled_sched_params(int pf_fd,
> +						  const uint8_t *vf_ids,
> +						  size_t num_functions)
> +{
> +	for (size_t n = 0; n < num_functions; ++n) {
> +		uint32_t exec_quantum_ms =
> +			xe_sriov_admin_get_exec_quantum_ms(pf_fd, vf_ids[n]);
> +		uint32_t preempt_timeout_us =
> +			xe_sriov_admin_get_preempt_timeout_us(pf_fd, vf_ids[n]);
> +		enum xe_sriov_sched_priority priority =
> +			xe_sriov_admin_get_sched_priority(pf_fd, vf_ids[n], NULL);
> +
> +		igt_require_f(exec_quantum_ms > 0,
> +			      "%s exec_quantum_ms stayed at 0 after enabling VFs\n",
> +			      igt_sriov_func_str(vf_ids[n]));
> +		igt_require_f(preempt_timeout_us > 0,
> +			      "%s preempt_timeout_us stayed at 0 after enabling VFs\n",
> +			      igt_sriov_func_str(vf_ids[n]));
> +		igt_warn_on_f(priority != XE_SRIOV_SCHED_PRIORITY_LOW,
> +			      "%s expected LOW sched_priority after enabling VFs, got %s\n",
> +			      igt_sriov_func_str(vf_ids[n]),
> +			      xe_sriov_sched_priority_to_string(priority));
> +	}
> +}
> +
> +static void ensure_enabled_vfs(int pf_fd, int num_vfs)
> +{
> +	unsigned int enabled_vfs = igt_sriov_get_enabled_vfs(pf_fd);
> +
> +	if (enabled_vfs && enabled_vfs != (unsigned int)num_vfs) {
> +		xe_sriov_disable_vfs_restore_auto_provisioning(pf_fd);
> +		enabled_vfs = 0;
> +	}
> +
> +	if (!enabled_vfs) {
> +		xe_sriov_require_default_scheduling_attributes(pf_fd);
> +		igt_sriov_enable_driver_autoprobe(pf_fd);
> +		igt_sriov_enable_vfs(pf_fd, num_vfs);
> +	}
> +}
> +
> +/**
> + * SUBTEST: default-enabled-fair-scheduling
> + * Description:
> + *   Check PF and enabled VFs keep fair scheduling using the driver-applied
> + *   default scheduling settings established when VFs are enabled.
> + */
> +static void default_enabled_fair_scheduling(int pf_fd, int num_vfs,
> +					    const struct subm_opts *opts,
> +					    bool verify_with_perf_counters,
> +					    const struct drm_xe_engine_class_instance *eci)
> +{
> +	uint8_t vf_ids[num_vfs + 1 /*PF*/];
> +	uint32_t job_timeout_ms = sysfs_get_job_timeout_ms(pf_fd, eci);
> +	struct job_sched_params job_sched_params;
> +
> +	ensure_enabled_vfs(pf_fd, num_vfs);
> +
> +	init_vf_ids(vf_ids, ARRAY_SIZE(vf_ids),
> +		    &(struct init_vf_ids_opts){ .shuffle = true,
> +						.shuffle_pf = true });
> +	validate_default_enabled_sched_params(pf_fd, vf_ids, ARRAY_SIZE(vf_ids));
> +	job_sched_params = prepare_default_enabled_job_sched_params(pf_fd, vf_ids,
> +								    ARRAY_SIZE(vf_ids),
> +								    job_timeout_ms);
> +
> +	verify_applied_scheduling_behavior(pf_fd, vf_ids, ARRAY_SIZE(vf_ids), opts,
> +					   verify_with_perf_counters, eci,
> +					   &job_sched_params);
> +}
> +
>   static bool skip_visited_gt(bool extended_scope, uint64_t *visited_gts,
>   			    unsigned short gt_id)
>   {
> @@ -1370,6 +1476,45 @@ int igt_main_args("", long_opts, help_str, subm_opts_handler, NULL)
>   				  has_perf_event(perf_device, "engine-total-ticks");
>   	}
>   
> +	igt_describe("Check PF and VFs keep fair scheduling using driver defaults applied on VF enable");
> +	igt_subtest_with_dynamic("default-enabled-fair-scheduling") {
> +		if (extended_scope)
> +			for_each_sriov_num_vfs(pf_fd, vf)
> +				xe_for_each_engine(pf_fd, eci) {
> +					ecls = eci->engine_class;
> +					igt_dynamic_f("numvfs-%d-gt%u-%s%u", vf,
> +						      eci->gt_id,
> +						      xe_engine_class_short_string(ecls),
> +						      eci->engine_instance)
> +						default_enabled_fair_scheduling(pf_fd, vf,
> +										&subm_opts,
> +										has_perf_events,
> +										eci);
> +				}
> +
> +		for_random_sriov_vf(pf_fd, vf) {
> +			uint64_t visited_gts = 0;
> +
> +			xe_for_each_engine(pf_fd, eci) {
> +				if (skip_visited_gt(extended_scope, &visited_gts,
> +						    eci->gt_id))
> +					continue;
> +
> +				igt_dynamic_f("numvfs-random-gt%u-%s%u",
> +					      eci->gt_id,
> +					      xe_engine_class_short_string(eci->engine_class),
> +					      eci->engine_instance)
> +					default_enabled_fair_scheduling(pf_fd, vf, &subm_opts,
> +									has_perf_events,
> +									eci);
> +			}
> +		}
> +	}
> +
> +	igt_fixture() {
> +		xe_sriov_disable_vfs_restore_auto_provisioning(pf_fd);
> +	}
> +
>   	for (enum xe_sriov_sched_priority priority = XE_SRIOV_SCHED_PRIORITY_LOW;
>   	     priority <= XE_SRIOV_SCHED_PRIORITY_NORMAL;
>   	     priority++) {