[PATCH v5 6/8] drm/etnaviv: Use DRM_GPU_SCHED_STAT_NO_HANG to skip the reset

[Maíra Canal]

Etnaviv can skip a hardware reset in two situations:

  1. TDR has fired before the free-job worker and the timeout is spurious.
  2. The GPU is still making progress on the front-end and we can give
     the job a chance to complete.

Instead of manipulating scheduler's internals, inform the scheduler that
the job did not actually timeout and no reset was performed through
the new status code DRM_GPU_SCHED_STAT_NO_HANG.

Signed-off-by: Maíra Canal <mca...@igalia.com>
Reviewed-by: Lucas Stach <l.st...@pengutronix.de>
---
 drivers/gpu/drm/etnaviv/etnaviv_sched.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c 
b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
index 
030e6c3233bed9edd5d9c2f49f842f604e57fc1c..46f5391e84a12232b247886cf1311f8e09f42f04
 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
@@ -35,17 +35,16 @@ static enum drm_gpu_sched_stat 
etnaviv_sched_timedout_job(struct drm_sched_job
                                                          *sched_job)
 {
        struct etnaviv_gem_submit *submit = to_etnaviv_submit(sched_job);
-       struct drm_gpu_scheduler *sched = sched_job->sched;
        struct etnaviv_gpu *gpu = submit->gpu;
        u32 dma_addr, primid = 0;
        int change;
 
        /*
-        * If the GPU managed to complete this jobs fence, the timout is
-        * spurious. Bail out.
+        * If the GPU managed to complete this jobs fence, the timeout has
+        * fired before free-job worker. The timeout is spurious, so bail out.
         */
        if (dma_fence_is_signaled(submit->out_fence))
-               goto out_no_timeout;
+               return DRM_GPU_SCHED_STAT_NO_HANG;
 
        /*
         * If the GPU is still making forward progress on the front-end (which
@@ -71,7 +70,7 @@ static enum drm_gpu_sched_stat 
etnaviv_sched_timedout_job(struct drm_sched_job
                gpu->hangcheck_dma_addr = dma_addr;
                gpu->hangcheck_primid = primid;
                gpu->hangcheck_fence = gpu->completed_fence;
-               goto out_no_timeout;
+               return DRM_GPU_SCHED_STAT_NO_HANG;
        }
 
        /* block scheduler */
@@ -87,12 +86,7 @@ static enum drm_gpu_sched_stat 
etnaviv_sched_timedout_job(struct drm_sched_job
        drm_sched_resubmit_jobs(&gpu->sched);
 
        drm_sched_start(&gpu->sched, 0);
-       return DRM_GPU_SCHED_STAT_RESET;
 
-out_no_timeout:
-       spin_lock(&sched->job_list_lock);
-       list_add(&sched_job->list, &sched->pending_list);
-       spin_unlock(&sched->job_list_lock);
        return DRM_GPU_SCHED_STAT_RESET;
 }
 

-- 
2.50.0