From: Rob Clark <robdclark@chromium.org>
Date: Tue, 2 Aug 2022 15:51:48 +0000 (-0700)
Subject: drm/msm/gem: Convert to lockdep assert
X-Git-Tag: v6.6.17~6279^2~3^2~88
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d95c196ddb6ccd2445760b003e6e8a43cd5e84ba;p=platform%2Fkernel%2Flinux-rpi.git

drm/msm/gem: Convert to lockdep assert

Utilize the power of lockdep for our GEM locking related sanity
checking.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/496139/
Link: https://lore.kernel.org/r/20220802155152.1727594-16-robdclark@gmail.com
---

diff --git a/drivers/gpu/drm/msm/msm_gem.h b/drivers/gpu/drm/msm/msm_gem.h
index 3c6add5..c4844cf 100644
--- a/drivers/gpu/drm/msm/msm_gem.h
+++ b/drivers/gpu/drm/msm/msm_gem.h
@@ -197,8 +197,8 @@ msm_gem_unlock(struct drm_gem_object *obj)
 	dma_resv_unlock(obj->resv);
 }
 
-static inline bool
-msm_gem_is_locked(struct drm_gem_object *obj)
+static inline void
+msm_gem_assert_locked(struct drm_gem_object *obj)
 {
 	/*
 	 * Destroying the object is a special case.. msm_gem_free_object()
@@ -212,13 +212,10 @@ msm_gem_is_locked(struct drm_gem_object *obj)
 	 * Unfortunately lockdep is not aware of this detail.  So when the
 	 * refcount drops to zero, we pretend it is already locked.
 	 */
-	return dma_resv_is_locked(obj->resv) || (kref_read(&obj->refcount) == 0);
-}
-
-static inline void
-msm_gem_assert_locked(struct drm_gem_object *obj)
-{
-	GEM_WARN_ON(!msm_gem_is_locked(obj));
+	lockdep_assert_once(
+		(kref_read(&obj->refcount) == 0) ||
+		(lockdep_is_held(&obj->resv->lock.base) != LOCK_STATE_NOT_HELD)
+	);
 }
 
 /* imported/exported objects are not purgeable: */