From: Bhawanpreet Lakha <[email protected]> why: amdgpu_dm_crtc_reset_state has a branch that destroys an already-installed crtc state before allocating a new one. Only the NULL-state branch was covered, leaving the state-replacement path untested.
how: Add dm_test_crtc_reset_state_replaces_existing, which installs a plain dm_crtc_state holding an extra stream reference, calls reset_state, and verifies the old state was destroyed (stream ref dropped) and a fresh non-NULL state was installed. Register the new case under the existing reset_state group. Reviewed-by: Alex Hung <[email protected]> Signed-off-by: Bhawanpreet Lakha <[email protected]> Signed-off-by: Tom Chung <[email protected]> --- .../amdgpu_dm/tests/amdgpu_dm_crtc_test.c | 43 +++++++++++++++++++ 1 file changed, 43 insertions(+) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_crtc_test.c b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_crtc_test.c index 1af819113168..430765dd87a3 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_crtc_test.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_crtc_test.c @@ -1531,6 +1531,48 @@ static void dm_test_crtc_reset_state_allocates_state(struct kunit *test) amdgpu_dm_crtc_destroy_state(crtc, crtc->state); } +/** + * dm_test_crtc_reset_state_replaces_existing - Test reset frees the old state + * @test: The KUnit test context + * + * Resetting a CRTC that already carries a state must destroy the existing + * state before installing a fresh one. The old state holds a stream reference, + * so a successful reset drops that reference (via amdgpu_dm_crtc_destroy_state) + * and leaves the CRTC with a new, non-NULL state. + */ +static void dm_test_crtc_reset_state_replaces_existing(struct kunit *test) +{ + struct amdgpu_device *adev = dm_kunit_alloc_adev(test); + struct dc_stream_state *stream; + struct dm_crtc_state *old; + struct drm_crtc *crtc; + struct dc_link *link; + + crtc = kunit_kzalloc(test, sizeof(*crtc), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, crtc); + crtc->dev = &adev->ddev; + + link = dm_kunit_alloc_link(test); + stream = dm_kunit_alloc_stream(test, link); + /* Extra ref so destroying the old state drops back to the managed one. */ + kref_get(&stream->refcount); + + /* reset_state kfree()s the old state, so use a plain (unmanaged) alloc. */ + old = kzalloc_obj(*old, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, old); + old->stream = stream; + crtc->state = &old->base; + + amdgpu_dm_crtc_reset_state(crtc); + + /* Old state was destroyed (stream ref dropped) and a new one installed. */ + KUNIT_EXPECT_EQ(test, kref_read(&stream->refcount), 1); + KUNIT_EXPECT_NOT_NULL(test, crtc->state); + + if (crtc->state) + amdgpu_dm_crtc_destroy_state(crtc, crtc->state); +} + /* Tests for amdgpu_dm_crtc_destroy_state() */ /** @@ -2013,6 +2055,7 @@ static struct kunit_case amdgpu_dm_crtc_tests[] = { KUNIT_CASE(dm_test_crtc_destroy_cleans_up_and_frees), /* amdgpu_dm_crtc_reset_state */ KUNIT_CASE(dm_test_crtc_reset_state_allocates_state), + KUNIT_CASE(dm_test_crtc_reset_state_replaces_existing), /* amdgpu_dm_crtc_destroy_state */ KUNIT_CASE(dm_test_crtc_destroy_state_no_stream), KUNIT_CASE(dm_test_crtc_destroy_state_releases_stream), -- 2.43.0
