re #13613 rb4516 Tunables needs volatile keyword

@@ -20,10 +20,13 @@
  */
 /*
  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
+/*
+ * Copyright 2013 Nexenta Systems, Inc.  All rights reserved.
+ */
 
 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
 /*        All Rights Reserved   */
 
 

@@ -118,11 +121,11 @@
  * Parameter that determines how recently a thread must have run
  * on the CPU to be considered loosely-bound to that CPU to reduce
  * cold cache effects.  The interval is in hertz.
  */
 #define RECHOOSE_INTERVAL 3
-int     rechoose_interval = RECHOOSE_INTERVAL;
+volatile int    rechoose_interval = RECHOOSE_INTERVAL;
 
 /*
  * Parameter that determines how long (in nanoseconds) a thread must
  * be sitting on a run queue before it can be stolen by another CPU
  * to reduce migrations.  The interval is in nanoseconds.