spinlock/mem.spin

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License as published by
   4  * the Free Software Foundation; either version 2 of the License, or
   5  * (at your option) any later version.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program; if not, write to the Free Software
  14  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  15  *
  16  * Copyright (c) 2009 Mathieu Desnoyers
  17  */
  18
  19 byte lock = 0;
  20 byte refcount = 0;
  21
  22 inline spin_lock(lock)
  23 {
  24         atomic{ !lock -> lock = 1}
  25 }
  26
  27 inline spin_unlock(lock)
  28 {
  29         lock = 0;
  30 }
  31
  32 proctype proc_X()
  33 {
  34         do
  35         ::      spin_lock(lock);
  36                 refcount = refcount + 1;
  37                 refcount = refcount - 1;
  38                 spin_unlock(lock);
  39         od;
  40 }
  41
  42 init
  43 {
  44         run proc_X();
  45         run proc_X();
  46 }