[PATCH v2] drm/i915/gvt: Use fence error from GVT request for workload status

[Chuanxiao Dong]

The req->fence.error will be set if this request caused GPU hang so
we can use this value to workload->status to indicate whether this
GVT request caused any problem. If it caused GPU hang, we shouldn't
trigger any context switch back to the guest.

v2:
- only take -EIO from fence->error. (Zhenyu)

Fixes: 8f1117abb408 (drm/i915/gvt: handle workload lifecycle properly)
Signed-off-by: Chuanxiao Dong <chuanxiao.dong at intel.com>
Cc: Zhenyu Wang <zhenyuw at linux.intel.com>
---
 drivers/gpu/drm/i915/gvt/scheduler.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c
index 5aeba13..4f7057d 100644
--- a/drivers/gpu/drm/i915/gvt/scheduler.c
+++ b/drivers/gpu/drm/i915/gvt/scheduler.c
@@ -174,15 +174,6 @@ static int shadow_context_status_change(struct notifier_block *nb,
 		atomic_set(&workload->shadow_ctx_active, 1);
 		break;
 	case INTEL_CONTEXT_SCHEDULE_OUT:
-		/* If the status is -EINPROGRESS means this workload
-		 * doesn't meet any issue during dispatching so when
-		 * get the SCHEDULE_OUT set the status to be zero for
-		 * good. If the status is NOT -EINPROGRESS means there
-		 * is something wrong happened during dispatching and
-		 * the status should not be set to zero
-		 */
-		if (workload->status == -EINPROGRESS)
-			workload->status = 0;
 		atomic_set(&workload->shadow_ctx_active, 0);
 		break;
 	default:
@@ -427,6 +418,18 @@ static void complete_current_workload(struct intel_gvt *gvt, int ring_id)
 		wait_event(workload->shadow_ctx_status_wq,
 			   !atomic_read(&workload->shadow_ctx_active));
 
+		/* If this request caused GPU hang, req->fence.error will
+		 * be set to -EIO. Use -EIO to set workload status so
+		 * that when this request caused GPU hang, didn't trigger
+		 * context switch interrupt to guest.
+		 */
+		if (likely(workload->status == -EINPROGRESS)) {
+			if (workload->req->fence.error == -EIO)
+				workload->status = -EIO;
+			else
+				workload->status = 0;
+		}
+
 		i915_gem_request_put(fetch_and_zero(&workload->req));
 
 		if (!workload->status && !vgpu->resetting) {
-- 
2.7.4