drm/msm/gpu: Skip retired submits in recover worker

If we somehow raced with submit retiring, either while waiting for
worker to have a chance to run or acquiring the gpu lock, then the
recover worker should just bail.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/568034/

diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index 2b7c9db3ded3f2a87c97273ab5e84fdf6fb1a623..095390774f22b547668227ed492a6e9783b055f9 100644 (file)
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -365,29 +365,31 @@ static void recover_worker(struct kthread_work *work)
        DRM_DEV_ERROR(dev->dev, "%s: hangcheck recover!\n", gpu->name);
 
        submit = find_submit(cur_ring, cur_ring->memptrs->fence + 1);
-       if (submit) {
-               /* Increment the fault counts */
-               submit->queue->faults++;
-               if (submit->aspace)
-                       submit->aspace->faults++;
 
-               get_comm_cmdline(submit, &comm, &cmd);
+       /*
+        * If the submit retired while we were waiting for the worker to run,
+        * or waiting to acquire the gpu lock, then nothing more to do.
+        */
+       if (!submit)
+               goto out_unlock;
 
-               if (comm && cmd) {
-                       DRM_DEV_ERROR(dev->dev, "%s: offending task: %s (%s)\n",
-                               gpu->name, comm, cmd);
+       /* Increment the fault counts */
+       submit->queue->faults++;
+       if (submit->aspace)
+               submit->aspace->faults++;
 
-                       msm_rd_dump_submit(priv->hangrd, submit,
-                               "offending task: %s (%s)", comm, cmd);
-               } else {
-                       msm_rd_dump_submit(priv->hangrd, submit, NULL);
-               }
+       get_comm_cmdline(submit, &comm, &cmd);
+
+       if (comm && cmd) {
+               DRM_DEV_ERROR(dev->dev, "%s: offending task: %s (%s)\n",
+                             gpu->name, comm, cmd);
+
+               msm_rd_dump_submit(priv->hangrd, submit,
+                                  "offending task: %s (%s)", comm, cmd);
        } else {
-               /*
-                * We couldn't attribute this fault to any particular context,
-                * so increment the global fault count instead.
-                */
-               gpu->global_faults++;
+               DRM_DEV_ERROR(dev->dev, "%s: offending task: unknown\n", gpu->name);
+
+               msm_rd_dump_submit(priv->hangrd, submit, NULL);
        }
 
        /* Record the crash state */
@@ -440,6 +442,7 @@ static void recover_worker(struct kthread_work *work)
 
        pm_runtime_put(&gpu->pdev->dev);
 
+out_unlock:
        mutex_unlock(&gpu->lock);
 
        msm_gpu_retire(gpu);