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+/******************************************************************************
+ *
+ * Copyright © International Business Machines Corp., 2009
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * DESCRIPTION
+ * GCC atomic builtin wrappers
+ * http://gcc.gnu.org/onlinedocs/gcc-4.1.0/gcc/Atomic-Builtins.html
+ *
+ * AUTHOR
+ * Darren Hart <dvhart@linux.intel.com>
+ *
+ * HISTORY
+ * 2009-Nov-17: Initial version by Darren Hart <dvhart@linux.intel.com>
+ *
+ *****************************************************************************/
+
+#ifndef _ATOMIC_H
+#define _ATOMIC_H
+
+typedef struct {
+ volatile int val;
+} atomic_t;
+
+#define ATOMIC_INITIALIZER { 0 }
+
+/**
+ * atomic_cmpxchg() - Atomic compare and exchange
+ * @uaddr: The address of the futex to be modified
+ * @oldval: The expected value of the futex
+ * @newval: The new value to try and assign the futex
+ *
+ * Return the old value of addr->val.
+ */
+static inline int
+atomic_cmpxchg(atomic_t *addr, int oldval, int newval)
+{
+ return __sync_val_compare_and_swap(&addr->val, oldval, newval);
+}
+
+/**
+ * atomic_inc() - Atomic incrememnt
+ * @addr: Address of the variable to increment
+ *
+ * Return the new value of addr->val.
+ */
+static inline int
+atomic_inc(atomic_t *addr)
+{
+ return __sync_add_and_fetch(&addr->val, 1);
+}
+
+/**
+ * atomic_dec() - Atomic decrement
+ * @addr: Address of the variable to decrement
+ *
+ * Return the new value of addr-val.
+ */
+static inline int
+atomic_dec(atomic_t *addr)
+{
+ return __sync_sub_and_fetch(&addr->val, 1);
+}
+
+/**
+ * atomic_set() - Atomic set
+ * @addr: Address of the variable to set
+ * @newval: New value for the atomic_t
+ *
+ * Return the new value of addr->val.
+ */
+static inline int
+atomic_set(atomic_t *addr, int newval)
+{
+ addr->val = newval;
+ return newval;
+}
+
+#endif