[PATCH] atomic: cmpxchg
Introduce an atomic_cmpxchg operation.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-xtensa/atomic.h b/include/asm-xtensa/atomic.h
index 12b5732..cd40c5e 100644
--- a/include/asm-xtensa/atomic.h
+++ b/include/asm-xtensa/atomic.h
@@ -223,6 +223,7 @@
*/
#define atomic_add_negative(i,v) (atomic_add_return((i),(v)) < 0)
+#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
{
