Re: [PATCH v4 14/23] drm/tests: hdmi: Add macro to support EDEADLK handling

[Cristian Ciocaltea <cristian.ciocaltea@collabora.com>]

On 5/19/25 10:22 AM, Maxime Ripard wrote:
> Hi,
> 
> On Fri, Apr 25, 2025 at 01:27:05PM +0300, Cristian Ciocaltea wrote:
>> In preparation to improve error handling throughout all test cases,
>> introduce a macro to check for EDEADLK and automate the restart of the
>> atomic sequence.
>>
>> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
>> ---
>>  drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c b/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
>> index c8969ee6518954ab4496d3a4398f428bf4104a36..c8bb131d63ea6d0c9e166c8d9ba5e403118cd9f1 100644
>> --- a/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
>> +++ b/drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c
>> @@ -224,6 +224,16 @@ drm_kunit_helper_connector_hdmi_init(struct kunit *test,
>>  				test_edid_hdmi_1080p_rgb_max_200mhz);
>>  }
>>  
>> +#define drm_kunit_atomic_restart_on_deadlock(ret, state, ctx, start) do {	\
>> +	if (ret == -EDEADLK) {							\
>> +		if (state)							\
>> +			drm_atomic_state_clear(state);				\
>> +		ret = drm_modeset_backoff(ctx);					\
>> +		if (!ret)							\
>> +			goto start;						\
>> +	}									\
>> +} while (0)
>> +
> 
> I'm not sure here either, for pretty much the same reason. As far as
> locking goes, I really think we should prefer something explicit even if
> it means a bit more boilerplate.
> 
> If you still want to push this forward though, this has nothing to do
> with kunit so it should be made a common helper. 

Ack.

> I do think it should be
> done in a separate series though. Ever-expanding series are a nightmare,
> both to contribute and to review :)

Indeed, let me take this separately.

If you agree, I'd prefer to drop EDEADLK handling from the new tests as
well, to allow sorting this out for all in a consistent manner.

Thanks,
Cristian