drm/scheduler: avoid infinite loop if entity's dependency is a scheduled error fence

[Why]
drm_sched_entity_add_dependency_cb ignores the scheduled fence and return false.
If entity's dependency is a scheduler error fence and drm_sched_stop is called
due to TDR, drm_sched_entity_pop_job will wait for the dependency infinitely.

[How]
Do not wait or ignore the scheduled error fence, add drm_sched_entity_wakeup
callback for the dependency with scheduled error fence.

Signed-off-by: ZhenGuo Yin <zhenguo.yin@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
index 68e807a..b2bbc8a 100644 (file)
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -384,7 +384,7 @@ static bool drm_sched_entity_add_dependency_cb(struct drm_sched_entity *entity)
        }
 
        s_fence = to_drm_sched_fence(fence);
-       if (s_fence && s_fence->sched == sched &&
+       if (!fence->error && s_fence && s_fence->sched == sched &&
            !test_bit(DRM_SCHED_FENCE_DONT_PIPELINE, &fence->flags)) {
 
                /*