drm/sched: Add a simple timeout test

Add a very simple timeout test which submits a single job and verifies
that the timeout handling will run if the backend failed to complete the
job in time.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Philipp Stanner <phasta@kernel.org>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Philipp Stanner <phasta@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250324092633.49746-4-tvrtko.ursulin@igalia.com

drivers/gpu/drm/scheduler/tests/mock_scheduler.c

@@ -203,7 +203,11 @@ static struct dma_fence *mock_sched_run_job(struct drm_sched_job *sched_job)
 static enum drm_gpu_sched_stat
 mock_sched_timedout_job(struct drm_sched_job *sched_job)
 {
-	return DRM_GPU_SCHED_STAT_ENODEV;
+	struct drm_mock_sched_job *job = drm_sched_job_to_mock_job(sched_job);
+
+	job->flags |= DRM_MOCK_SCHED_JOB_TIMEDOUT;
+
+	return DRM_GPU_SCHED_STAT_NOMINAL;
 }
 
 static void mock_sched_free_job(struct drm_sched_job *sched_job)
@@ -234,17 +238,18 @@ static const struct drm_sched_backend_ops drm_mock_scheduler_ops = {
  * drm_mock_sched_new - Create a new mock scheduler
  *
  * @test: KUnit test owning the job
+ * @timeout: Job timeout to set
  *
  * Returns: New mock scheduler with allocation managed by the test
  */
-struct drm_mock_scheduler *drm_mock_sched_new(struct kunit *test)
+struct drm_mock_scheduler *drm_mock_sched_new(struct kunit *test, long timeout)
 {
 	struct drm_sched_init_args args = {
 		.ops		= &drm_mock_scheduler_ops,
 		.num_rqs	= DRM_SCHED_PRIORITY_COUNT,
 		.credit_limit	= U32_MAX,
 		.hang_limit	= 1,
-		.timeout	= MAX_SCHEDULE_TIMEOUT,
+		.timeout	= timeout,
 		.name		= "drm-mock-scheduler",
 	};
 	struct drm_mock_scheduler *sched;

drivers/gpu/drm/scheduler/tests/sched_tests.h

@@ -97,6 +97,7 @@ struct drm_mock_sched_job {
 	struct completion	done;
 
 #define DRM_MOCK_SCHED_JOB_DONE		0x1
+#define DRM_MOCK_SCHED_JOB_TIMEDOUT	0x2
 	unsigned long		flags;
 
 	struct list_head	link;
@@ -129,7 +130,8 @@ drm_sched_job_to_mock_job(struct drm_sched_job *sched_job)
 	return container_of(sched_job, struct drm_mock_sched_job, base);
 };
 
-struct drm_mock_scheduler *drm_mock_sched_new(struct kunit *test);
+struct drm_mock_scheduler *drm_mock_sched_new(struct kunit *test,
+					      long timeout);
 void drm_mock_sched_fini(struct drm_mock_scheduler *sched);
 unsigned int drm_mock_sched_advance(struct drm_mock_scheduler *sched,
 				    unsigned int num);

drivers/gpu/drm/scheduler/tests/tests_basic.c

@@ -12,7 +12,7 @@
 
 static int drm_sched_basic_init(struct kunit *test)
 {
-	test->priv = drm_mock_sched_new(test);
+	test->priv = drm_mock_sched_new(test, MAX_SCHEDULE_TIMEOUT);
 
 	return 0;
 }
@@ -24,6 +24,13 @@ static void drm_sched_basic_exit(struct kunit *test)
 	drm_mock_sched_fini(sched);
 }
 
+static int drm_sched_timeout_init(struct kunit *test)
+{
+	test->priv = drm_mock_sched_new(test, HZ);
+
+	return 0;
+}
+
 static void drm_sched_basic_submit(struct kunit *test)
 {
 	struct drm_mock_scheduler *sched = test->priv;
@@ -195,4 +202,57 @@ static struct kunit_suite drm_sched_basic = {
 	.test_cases = drm_sched_basic_tests,
 };
 
-kunit_test_suite(drm_sched_basic);
+static void drm_sched_basic_timeout(struct kunit *test)
+{
+	struct drm_mock_scheduler *sched = test->priv;
+	struct drm_mock_sched_entity *entity;
+	struct drm_mock_sched_job *job;
+	bool done;
+
+	/*
+	 * Submit a single job against a scheduler with the timeout configured
+	 * and verify that the timeout handling will run if the backend fails
+	 * to complete it in time.
+	 */
+
+	entity = drm_mock_sched_entity_new(test,
+					   DRM_SCHED_PRIORITY_NORMAL,
+					   sched);
+	job = drm_mock_sched_job_new(test, entity);
+
+	drm_mock_sched_job_submit(job);
+
+	done = drm_mock_sched_job_wait_scheduled(job, HZ);
+	KUNIT_ASSERT_TRUE(test, done);
+
+	done = drm_mock_sched_job_wait_finished(job, HZ / 2);
+	KUNIT_ASSERT_FALSE(test, done);
+
+	KUNIT_ASSERT_EQ(test,
+			job->flags & DRM_MOCK_SCHED_JOB_TIMEDOUT,
+			0);
+
+	done = drm_mock_sched_job_wait_finished(job, HZ);
+	KUNIT_ASSERT_FALSE(test, done);
+
+	KUNIT_ASSERT_EQ(test,
+			job->flags & DRM_MOCK_SCHED_JOB_TIMEDOUT,
+			DRM_MOCK_SCHED_JOB_TIMEDOUT);
+
+	drm_mock_sched_entity_free(entity);
+}
+
+static struct kunit_case drm_sched_timeout_tests[] = {
+	KUNIT_CASE(drm_sched_basic_timeout),
+	{}
+};
+
+static struct kunit_suite drm_sched_timeout = {
+	.name = "drm_sched_basic_timeout_tests",
+	.init = drm_sched_timeout_init,
+	.exit = drm_sched_basic_exit,
+	.test_cases = drm_sched_timeout_tests,
+};
+
+kunit_test_suites(&drm_sched_basic,
+		  &drm_sched_timeout);