1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 7f47b7098b1b..279c7b84bd63 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -176,6 +176,12 @@ enum {
  * protected by swap_info_struct.lock.
  */
 struct swap_cluster_info {
+	spinlock_t lock;	/*
+				 * Protect swap_cluster_info fields
+				 * and swap_info_struct->swap_map
+				 * elements correspond to the swap
+				 * cluster
+				 */
 	unsigned int data:24;
 	unsigned int flags:8;
 };