[Intel-gfx] [PATCH i-g-t 2/4] i915/gem_ctx_engine: Exercise for_each_context_engine() with custom engine[]

[Chris Wilson]

Set up a custom engine map with no engines, and check that the
for_each_context_engine() correctly iterates over nothing.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 tests/i915/gem_ctx_engines.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/tests/i915/gem_ctx_engines.c b/tests/i915/gem_ctx_engines.c
index 063140e0f..6a2edd1e0 100644
--- a/tests/i915/gem_ctx_engines.c
+++ b/tests/i915/gem_ctx_engines.c
@@ -549,6 +549,31 @@ static void independent(int i915)
 	gem_context_destroy(i915, param.ctx_id);
 }
 
+static void libapi(int i915)
+{
+	struct i915_context_param_engines engines = {};
+	struct drm_i915_gem_context_param p = {
+		.ctx_id = gem_context_create(i915),
+		.param = I915_CONTEXT_PARAM_ENGINES,
+		.value = to_user_pointer(&engines),
+		.size = sizeof(engines),
+	};
+	const struct intel_execution_engine2 *e;
+	unsigned int count = 0;
+
+	gem_context_set_param(i915, &p);
+
+	for_each_context_engine(i915, p.ctx_id, e)
+		count++;
+	igt_assert_eq(count, 0);
+
+	____for_each_physical_engine(i915, p.ctx_id, e)
+		count++;
+	igt_assert_eq(count, 0);
+
+	gem_context_destroy(i915, p.ctx_id);
+}
+
 igt_main
 {
 	int i915 = -1;
@@ -584,6 +609,9 @@ igt_main
 	igt_subtest("independent")
 		independent(i915);
 
+	igt_subtest("libapi")
+		libapi(i915);
+
 	igt_fixture
 		igt_stop_hang_detector();
 }
-- 
2.25.0