drm/msm: print offender task name on hangcheck recovery

Track the pid per submit, so we can print the name of the task which
submitted the batch that caused the gpu to hang.

Signed-off-by: Rob Clark <robdclark@gmail.com>

1 files changed, 19 insertions, 4 deletions

diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index 5aed93a87e4c..36ed53e661fe 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -272,16 +272,30 @@ static void recover_worker(struct work_struct *work)
 {
 	struct msm_gpu *gpu = container_of(work, struct msm_gpu, recover_work);
 	struct drm_device *dev = gpu->dev;
+	struct msm_gem_submit *submit;
 	uint32_t fence = gpu->funcs->last_fence(gpu);
 
-	dev_err(dev->dev, "%s: hangcheck recover!\n", gpu->name);
-
 	msm_update_fence(gpu->fctx, fence + 1);
 
 	mutex_lock(&dev->struct_mutex);
-	if (msm_gpu_active(gpu)) {
-		struct msm_gem_submit *submit;
 
+	dev_err(dev->dev, "%s: hangcheck recover!\n", gpu->name);
+	list_for_each_entry(submit, &gpu->submit_list, node) {
+		if (submit->fence->seqno == (fence + 1)) {
+			struct task_struct *task;
+
+			rcu_read_lock();
+			task = pid_task(submit->pid, PIDTYPE_PID);
+			if (task) {
+				dev_err(dev->dev, "%s: offending task: %s\n",
+						gpu->name, task->comm);
+			}
+			rcu_read_unlock();
+			break;
+		}
+	}
+
+	if (msm_gpu_active(gpu)) {
 		/* retire completed submits, plus the one that hung: */
 		retire_submits(gpu);
 
@@ -293,6 +307,7 @@ static void recover_worker(struct work_struct *work)
 			gpu->funcs->submit(gpu, submit, NULL);
 		}
 	}
+
 	mutex_unlock(&dev->struct_mutex);
 
 	msm_gpu_retire(gpu);