[PATCH] drm/atomic: Make atomic helper track newly assigned planes correctly, v2.

[Maarten Lankhorst]

Op 17-10-17 om 14:11 schreef Daniel Vetter:
> On Tue, Oct 17, 2017 at 07:20:47AM +0200, Maarten Lankhorst wrote:
>> Commit 669c9215afea ("drm/atomic: Make async plane update checks work as
>> intended, v2.") forced planes to always be tracked, but forgot to
>> explicitly get the crtc commit from the new crtc when available.
>>
>> This broke plane commit tracking, and caused kms_atomic_transitions
>> to randomly fail with -EBUSY.
>>
>> Changes since v1:
>> - Prefer new_crtc_state->crtc above old_crtc_state->crtc.
>>
>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>> Fixes: 669c9215afea ("drm/atomic: Make async plane update checks work as intended, v2.")
>> Cc: Gustavo Padovan <gustavo.padovan at collabora.com>
>> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
>> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102671
>> Testcase: kms_atomic_transitions
> Do we need to make this testcase more effective at hitting this?
Not necessarily, the test already runs through all plane combinations and some of the transitions will likely hit it..

Test is still broken until IGT is fixed.
>> ---
>>  drivers/gpu/drm/drm_atomic_helper.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
>> index d59441f1dcd4..d0c2b266289e 100644
>> --- a/drivers/gpu/drm/drm_atomic_helper.c
>> +++ b/drivers/gpu/drm/drm_atomic_helper.c
>> @@ -1804,7 +1804,7 @@ int drm_atomic_helper_setup_commit(struct drm_atomic_state *state,
>>  		    !try_wait_for_completion(&old_plane_state->commit->flip_done))
>>  			return -EBUSY;
>>  
>> -		commit = crtc_or_fake_commit(state, old_plane_state->crtc);
>> +		commit = crtc_or_fake_commit(state, new_plane_state->crtc ?: old_plane_state->crtc);
> Maybe line-break and don't use the ?: gcc-ism. Either way
>
> Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
I like gcc-isms when it makes things easier. We use it in other places inside drm, and i915 anyway. :)

Thanks,
Pushed.