[PATCH 4/4] drm/vc4: tests: Retry pv-muxing tests when EDEADLK

From: Maxime Ripard
Date: Tue Mar 18 2025 - 10:20:02 EST


Some functions used by the HVS->PV muxing tests can return with EDEADLK,
meaning the entire sequence should be restarted. It's not a fatal error
and we should treat it as a recoverable error, and recover, instead of
failing the test like we currently do.

Fixes: 76ec18dc5afa ("drm/vc4: tests: Add unit test suite for the PV muxing")
Signed-off-by: Maxime Ripard <mripard@xxxxxxxxxx>
---
drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c | 44 ++++++++++++++++++++++++++
1 file changed, 44 insertions(+)

diff --git a/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c b/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c
index 52c04ef33206bf4f9e21e3c8b7cea932824a67fa..94e05bddb630a79aab189d9bc16f09a9d84ce396 100644
--- a/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c
+++ b/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c
@@ -685,20 +685,26 @@ static void drm_vc4_test_pv_muxing(struct kunit *test)

drm_modeset_acquire_init(&ctx, 0);

vc4 = priv->vc4;
drm = &vc4->base;
+
+retry:
state = drm_kunit_helper_atomic_state_alloc(test, drm, &ctx);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
for (i = 0; i < params->nencoders; i++) {
enum vc4_encoder_type enc_type = params->encoders[i];

ret = vc4_mock_atomic_add_output(test, state, enc_type);
+ if (ret == -EDEADLK)
+ goto retry;
KUNIT_ASSERT_EQ(test, ret, 0);
}

ret = drm_atomic_check_only(state);
+ if (ret == -EDEADLK)
+ goto retry;
KUNIT_EXPECT_EQ(test, ret, 0);

KUNIT_EXPECT_TRUE(test,
check_fifo_conflict(test, state));

@@ -726,21 +732,27 @@ static void drm_vc4_test_pv_muxing_invalid(struct kunit *test)

drm_modeset_acquire_init(&ctx, 0);

vc4 = priv->vc4;
drm = &vc4->base;
+
+retry:
state = drm_kunit_helper_atomic_state_alloc(test, drm, &ctx);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);

for (i = 0; i < params->nencoders; i++) {
enum vc4_encoder_type enc_type = params->encoders[i];

ret = vc4_mock_atomic_add_output(test, state, enc_type);
+ if (ret == -EDEADLK)
+ goto retry;
KUNIT_ASSERT_EQ(test, ret, 0);
}

ret = drm_atomic_check_only(state);
+ if (ret == -EDEADLK)
+ goto retry;
KUNIT_EXPECT_LT(test, ret, 0);

drm_modeset_drop_locks(&ctx);
drm_modeset_acquire_fini(&ctx);
}
@@ -811,17 +823,22 @@ static void drm_test_vc5_pv_muxing_bugs_subsequent_crtc_enable(struct kunit *tes
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, vc4);

drm_modeset_acquire_init(&ctx, 0);

drm = &vc4->base;
+retry_first:
state = drm_kunit_helper_atomic_state_alloc(test, drm, &ctx);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);

ret = vc4_mock_atomic_add_output(test, state, VC4_ENCODER_TYPE_HDMI0);
+ if (ret == -EDEADLK)
+ goto retry_first;
KUNIT_ASSERT_EQ(test, ret, 0);

ret = drm_atomic_check_only(state);
+ if (ret == -EDEADLK)
+ goto retry_first;
KUNIT_ASSERT_EQ(test, ret, 0);

new_hvs_state = vc4_hvs_get_new_global_state(state);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, new_hvs_state);

@@ -834,17 +851,22 @@ static void drm_test_vc5_pv_muxing_bugs_subsequent_crtc_enable(struct kunit *tes
KUNIT_ASSERT_TRUE(test, new_hvs_state->fifo_state[hdmi0_channel].in_use);

ret = drm_atomic_helper_swap_state(state, false);
KUNIT_ASSERT_EQ(test, ret, 0);

+retry_second:
state = drm_kunit_helper_atomic_state_alloc(test, drm, &ctx);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);

ret = vc4_mock_atomic_add_output(test, state, VC4_ENCODER_TYPE_HDMI1);
+ if (ret == -EDEADLK)
+ goto retry_second;
KUNIT_ASSERT_EQ(test, ret, 0);

ret = drm_atomic_check_only(state);
+ if (ret == -EDEADLK)
+ goto retry_second;
KUNIT_ASSERT_EQ(test, ret, 0);

new_hvs_state = vc4_hvs_get_new_global_state(state);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, new_hvs_state);

@@ -885,20 +907,27 @@ static void drm_test_vc5_pv_muxing_bugs_stable_fifo(struct kunit *test)
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, vc4);

drm_modeset_acquire_init(&ctx, 0);

drm = &vc4->base;
+retry_first:
state = drm_kunit_helper_atomic_state_alloc(test, drm, &ctx);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);

ret = vc4_mock_atomic_add_output(test, state, VC4_ENCODER_TYPE_HDMI0);
+ if (ret == -EDEADLK)
+ goto retry_first;
KUNIT_ASSERT_EQ(test, ret, 0);

ret = vc4_mock_atomic_add_output(test, state, VC4_ENCODER_TYPE_HDMI1);
+ if (ret == -EDEADLK)
+ goto retry_first;
KUNIT_ASSERT_EQ(test, ret, 0);

ret = drm_atomic_check_only(state);
+ if (ret == -EDEADLK)
+ goto retry_first;
KUNIT_ASSERT_EQ(test, ret, 0);

new_hvs_state = vc4_hvs_get_new_global_state(state);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, new_hvs_state);

@@ -919,17 +948,22 @@ static void drm_test_vc5_pv_muxing_bugs_stable_fifo(struct kunit *test)
KUNIT_ASSERT_TRUE(test, new_hvs_state->fifo_state[old_hdmi1_channel].in_use);

ret = drm_atomic_helper_swap_state(state, false);
KUNIT_ASSERT_EQ(test, ret, 0);

+retry_second:
state = drm_kunit_helper_atomic_state_alloc(test, drm, &ctx);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);

ret = vc4_mock_atomic_del_output(test, state, VC4_ENCODER_TYPE_HDMI0);
+ if (ret == -EDEADLK)
+ goto retry_second;
KUNIT_ASSERT_EQ(test, ret, 0);

ret = drm_atomic_check_only(state);
+ if (ret == -EDEADLK)
+ goto retry_second;
KUNIT_ASSERT_EQ(test, ret, 0);

new_hvs_state = vc4_hvs_get_new_global_state(state);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, new_hvs_state);

@@ -979,29 +1013,39 @@ drm_test_vc5_pv_muxing_bugs_subsequent_crtc_enable_too_many_crtc_state(struct ku
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, vc4);

drm_modeset_acquire_init(&ctx, 0);

drm = &vc4->base;
+retry_first:
state = drm_kunit_helper_atomic_state_alloc(test, drm, &ctx);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);

ret = vc4_mock_atomic_add_output(test, state, VC4_ENCODER_TYPE_HDMI0);
+ if (ret == -EDEADLK)
+ goto retry_first;
KUNIT_ASSERT_EQ(test, ret, 0);

ret = drm_atomic_check_only(state);
+ if (ret == -EDEADLK)
+ goto retry_first;
KUNIT_ASSERT_EQ(test, ret, 0);

ret = drm_atomic_helper_swap_state(state, false);
KUNIT_ASSERT_EQ(test, ret, 0);

+retry_second:
state = drm_kunit_helper_atomic_state_alloc(test, drm, &ctx);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);

ret = vc4_mock_atomic_add_output(test, state, VC4_ENCODER_TYPE_HDMI1);
+ if (ret == -EDEADLK)
+ goto retry_second;
KUNIT_ASSERT_EQ(test, ret, 0);

ret = drm_atomic_check_only(state);
+ if (ret == -EDEADLK)
+ goto retry_second;
KUNIT_ASSERT_EQ(test, ret, 0);

new_vc4_crtc_state = get_vc4_crtc_state_for_encoder(test, state,
VC4_ENCODER_TYPE_HDMI0);
KUNIT_EXPECT_NULL(test, new_vc4_crtc_state);

--
2.48.1