re #13613 rb4516 Tunables needs volatile keyword

@@ -18,10 +18,11 @@
  *
  * CDDL HEADER END
  */
 /*
  * Copyright (c) 1983, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright 2013 Nexenta Systems, Inc.  All rights reserved.
  */
 
 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
 /*        All Rights Reserved   */
 

@@ -482,11 +483,11 @@
 /*
  * Extended attributes
  */
 
 #define XATTR_DIR_NAME  "/@/"
-extern int      ufs_ninode;             /* high-water mark for inode cache */
+extern volatile int     ufs_ninode;     /* high-water mark for inode cache */
 
 extern struct vnodeops *ufs_vnodeops;   /* vnode operations for ufs */
 extern const struct fs_operation_def ufs_vnodeops_template[];
 
 /*