[3.11.y.z,extended,stable] Patch "drm/vmwgfx: Resource evict fixes" has been added to staging queue

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
index ad2b056..36508eb 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
@@ -32,6 +32,8 @@ 
 #include <drm/drmP.h>
 #include "vmwgfx_resource_priv.h"

+#define VMW_RES_EVICT_ERR_COUNT 10
+
 struct vmw_user_dma_buffer {
 	struct ttm_base_object base;
 	struct vmw_dma_buffer dma;
@@ -1091,8 +1093,9 @@  vmw_resource_backoff_reservation(struct ww_acquire_ctx *ticket,
  *                         to a backup buffer.
  *
  * @res:            The resource to evict.
+ * @interruptible:  Whether to wait interruptible.
  */
-int vmw_resource_do_evict(struct vmw_resource *res)
+int vmw_resource_do_evict(struct vmw_resource *res, bool interruptible)
 {
 	struct ttm_validate_buffer val_buf;
 	const struct vmw_res_func *func = res->func;
@@ -1102,7 +1105,8 @@  int vmw_resource_do_evict(struct vmw_resource *res)
 	BUG_ON(!func->may_evict);

 	val_buf.bo = NULL;
-	ret = vmw_resource_check_buffer(res, &ticket, true, &val_buf);
+	ret = vmw_resource_check_buffer(res, &ticket, interruptible,
+					&val_buf);
 	if (unlikely(ret != 0))
 		return ret;

@@ -1141,6 +1145,7 @@  int vmw_resource_validate(struct vmw_resource *res)
 	struct vmw_private *dev_priv = res->dev_priv;
 	struct list_head *lru_list = &dev_priv->res_lru[res->func->res_type];
 	struct ttm_validate_buffer val_buf;
+	unsigned err_count = 0;

 	if (likely(!res->func->may_evict))
 		return 0;
@@ -1155,7 +1160,7 @@  int vmw_resource_validate(struct vmw_resource *res)

 		write_lock(&dev_priv->resource_lock);
 		if (list_empty(lru_list) || !res->func->may_evict) {
-			DRM_ERROR("Out of device device id entries "
+			DRM_ERROR("Out of device device resources "
 				  "for %s.\n", res->func->type_name);
 			ret = -EBUSY;
 			write_unlock(&dev_priv->resource_lock);
@@ -1168,7 +1173,19 @@  int vmw_resource_validate(struct vmw_resource *res)
 		list_del_init(&evict_res->lru_head);

 		write_unlock(&dev_priv->resource_lock);
-		vmw_resource_do_evict(evict_res);
+
+		ret = vmw_resource_do_evict(evict_res, true);
+		if (unlikely(ret != 0)) {
+			write_lock(&dev_priv->resource_lock);
+			list_add_tail(&evict_res->lru_head, lru_list);
+			write_unlock(&dev_priv->resource_lock);
+			if (ret == -ERESTARTSYS ||
+			    ++err_count > VMW_RES_EVICT_ERR_COUNT) {
+				vmw_resource_unreference(&evict_res);
+				goto out_no_validate;
+			}
+		}
+
 		vmw_resource_unreference(&evict_res);
 	} while (1);

@@ -1253,13 +1270,15 @@  bool vmw_resource_needs_backup(const struct vmw_resource *res)
  * @type:           The resource type to evict
  *
  * To avoid thrashing starvation or as part of the hibernation sequence,
- * evict all evictable resources of a specific type.
+ * try to evict all evictable resources of a specific type.
  */
 static void vmw_resource_evict_type(struct vmw_private *dev_priv,
 				    enum vmw_res_type type)
 {
 	struct list_head *lru_list = &dev_priv->res_lru[type];
 	struct vmw_resource *evict_res;
+	unsigned err_count = 0;
+	int ret;

 	do {
 		write_lock(&dev_priv->resource_lock);
@@ -1272,7 +1291,18 @@  static void vmw_resource_evict_type(struct vmw_private *dev_priv,
 					 lru_head));
 		list_del_init(&evict_res->lru_head);
 		write_unlock(&dev_priv->resource_lock);
-		vmw_resource_do_evict(evict_res);
+
+		ret = vmw_resource_do_evict(evict_res, false);
+		if (unlikely(ret != 0)) {
+			write_lock(&dev_priv->resource_lock);
+			list_add_tail(&evict_res->lru_head, lru_list);
+			write_unlock(&dev_priv->resource_lock);
+			if (++err_count > VMW_RES_EVICT_ERR_COUNT) {
+				vmw_resource_unreference(&evict_res);
+				return;
+			}
+		}
+
 		vmw_resource_unreference(&evict_res);
 	} while (1);