[PATCH] drm/ttm: do not check if list is empty in ttm_bo_force_list_clean, v2

[Maarten Lankhorst <maarten.lankhorst@canonical.com>]

Just use the return error from ttm_mem_evict_first instead.

Changes since v1:
- Add warning if list is not empty, nothing else we can do here.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
---
 drivers/gpu/drm/ttm/ttm_bo.c |   30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 8ab23ae..9028327 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -1323,25 +1323,25 @@ static int ttm_bo_force_list_clean(struct ttm_bo_device *bdev,
 	struct ttm_bo_global *glob = bdev->glob;
 	int ret;
 
-	/*
-	 * Can't use standard list traversal since we're unlocking.
-	 */
-
-	spin_lock(&glob->lru_lock);
-	while (!list_empty(&man->lru)) {
-		spin_unlock(&glob->lru_lock);
+	do {
 		ret = ttm_mem_evict_first(bdev, mem_type, false, false);
-		if (ret) {
-			if (allow_errors) {
-				return ret;
-			} else {
-				pr_err("Cleanup eviction failed\n");
-			}
+		if (ret && ret != -EBUSY && !allow_errors) {
+			pr_err("Cleanup eviction failed with %i\n", ret);
+			ret = 0;
 		}
+	} while (!ret);
+
+	if (likely(ret == -EBUSY)) {
+		/*
+		* lru list should be empty, verify this is the case.
+		*/
 		spin_lock(&glob->lru_lock);
+		WARN_ON(!list_empty(&man->lru));
+		if (list_empty(&man->lru) || !allow_errors)
+			ret = 0;
+		spin_unlock(&glob->lru_lock);
 	}
-	spin_unlock(&glob->lru_lock);
-	return 0;
+	return ret;
 }
 
 int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type)