drm/scheduler: deprecate drm_sched_resubmit_jobs

This interface is not working as it should.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221109095010.141189-5-christian.koenig@amd.com

diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index fd22d75..0e43784 100644 (file)
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -551,10 +551,21 @@ void drm_sched_start(struct drm_gpu_scheduler *sched, bool full_recovery)
 EXPORT_SYMBOL(drm_sched_start);
 
 /**
- * drm_sched_resubmit_jobs - helper to relaunch jobs from the pending list
+ * drm_sched_resubmit_jobs - Deprecated, don't use in new code!
  *
  * @sched: scheduler instance
  *
+ * Re-submitting jobs was a concept AMD came up as cheap way to implement
+ * recovery after a job timeout.
+ *
+ * This turned out to be not working very well. First of all there are many
+ * problem with the dma_fence implementation and requirements. Either the
+ * implementation is risking deadlocks with core memory management or violating
+ * documented implementation details of the dma_fence object.
+ *
+ * Drivers can still save and restore their state for recovery operations, but
+ * we shouldn't make this a general scheduler feature around the dma_fence
+ * interface.
  */
 void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched)
 {