[Intel-gfx] [PATCH] drm/i915/gt: Flush ongoing retires during wait_for_idle

[Chris Wilson]

Synchronise with any background retires and parking we may have spawned,
so that all requests are accounted for.

Closes: https://gitlab.freedesktop.org/drm/intel/issues/878
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/gt/intel_gt_requests.c | 14 +++++++++-----
 drivers/gpu/drm/i915/intel_wakeref.c        |  7 +++++--
 drivers/gpu/drm/i915/intel_wakeref.h        |  9 +++++++--
 3 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
index fc691c130ba6..0c3d8517010a 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
@@ -26,18 +26,22 @@ static bool retire_requests(struct intel_timeline *tl)
 	return !i915_active_fence_isset(&tl->last_request);
 }
 
-static void flush_submission(struct intel_gt *gt)
+static bool flush_submission(struct intel_gt *gt)
 {
 	struct intel_engine_cs *engine;
 	enum intel_engine_id id;
+	bool active = false;
 
 	if (!intel_gt_pm_is_awake(gt))
-		return;
+		return false;;
 
 	for_each_engine(engine, gt, id) {
 		intel_engine_flush_submission(engine);
-		flush_work(&engine->retire_work);
+		active |= flush_work(&engine->retire_work);
+		active |= flush_work(&engine->wakeref.work);
 	}
+
+	return active;
 }
 
 static void engine_retire(struct work_struct *work)
@@ -147,9 +151,9 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
 			}
 		}
 
-		active_count += !retire_requests(tl);
+		if (!retire_requests(tl) || flush_submission(gt))
+			active_count++;
 
-		flush_submission(gt); /* sync with concurrent retirees */
 		spin_lock(&timelines->lock);
 
 		/* Resume iteration after dropping lock */
diff --git a/drivers/gpu/drm/i915/intel_wakeref.c b/drivers/gpu/drm/i915/intel_wakeref.c
index 59aa1b6f1827..1a57898d5a06 100644
--- a/drivers/gpu/drm/i915/intel_wakeref.c
+++ b/drivers/gpu/drm/i915/intel_wakeref.c
@@ -95,16 +95,19 @@ static void __intel_wakeref_put_work(struct work_struct *wrk)
 void __intel_wakeref_init(struct intel_wakeref *wf,
 			  struct intel_runtime_pm *rpm,
 			  const struct intel_wakeref_ops *ops,
-			  struct lock_class_key *key)
+			  struct intel_wakeref_lockclass *key)
 {
 	wf->rpm = rpm;
 	wf->ops = ops;
 
-	__mutex_init(&wf->mutex, "wakeref", key);
+	__mutex_init(&wf->mutex, "wakeref.mutex", &key->mutex);
 	atomic_set(&wf->count, 0);
 	wf->wakeref = 0;
 
 	INIT_WORK(&wf->work, __intel_wakeref_put_work);
+#ifdef CONFIG_LOCKDEP
+	lockdep_init_map(&wf->work.lockdep_map, "wakeref.work", &key->work, 0);
+#endif
 }
 
 int intel_wakeref_wait_for_idle(struct intel_wakeref *wf)
diff --git a/drivers/gpu/drm/i915/intel_wakeref.h b/drivers/gpu/drm/i915/intel_wakeref.h
index 8d945db94b7a..7d1e676b71ef 100644
--- a/drivers/gpu/drm/i915/intel_wakeref.h
+++ b/drivers/gpu/drm/i915/intel_wakeref.h
@@ -44,12 +44,17 @@ struct intel_wakeref {
 	struct work_struct work;
 };
 
+struct intel_wakeref_lockclass {
+	struct lock_class_key mutex;
+	struct lock_class_key work;
+};
+
 void __intel_wakeref_init(struct intel_wakeref *wf,
 			  struct intel_runtime_pm *rpm,
 			  const struct intel_wakeref_ops *ops,
-			  struct lock_class_key *key);
+			  struct intel_wakeref_lockclass *key);
 #define intel_wakeref_init(wf, rpm, ops) do {				\
-	static struct lock_class_key __key;				\
+	static struct intel_wakeref_lockclass __key;			\
 									\
 	__intel_wakeref_init((wf), (rpm), (ops), &__key);		\
 } while (0)
-- 
2.25.0.rc0