re #13613 rb4516 Tunables needs volatile keyword

*** 19,31 ****
--- 19,33 ----
   * CDDL HEADER END
   */
  
  /*
   * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
+  * Copyright 2013 Nexenta Systems, Inc.  All rights reserved.
   */
  
  #include <sys/types.h>
+ #include <sys/vmsystm.h>
  #include <inet/common.h>
  #include "sctp_impl.h"
  
  /* Control whether SCTP can enter defensive mode when under memory pressure. */
  static boolean_t sctp_do_reclaim = B_TRUE;
*** 152,162 ****
  sctp_reclaim_timer(void *arg)
  {
          sctp_stack_t *sctps = (sctp_stack_t *)arg;
          int64_t tot_assoc = 0;
          int i;
-         extern pgcnt_t lotsfree, needfree;
  
          for (i = 0; i < sctps->sctps_sc_cnt; i++)
                  tot_assoc += sctps->sctps_sc[i]->sctp_sc_assoc_cnt;
  
          /*
--- 154,163 ----
*** 193,203 ****
  sctp_conn_reclaim(void *arg)
  {
          netstack_handle_t nh;
          netstack_t *ns;
          sctp_stack_t *sctps;
-         extern pgcnt_t lotsfree, needfree;
  
          if (!sctp_do_reclaim)
                  return;
  
          /*
--- 194,203 ----