[PATCH] mutex subsystem, add atomic_xchg() to all arches
add atomic_xchg() to all the architectures. Needed by the new mutex code.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
diff --git a/include/asm-s390/atomic.h b/include/asm-s390/atomic.h
index d82aedf..be6fefe 100644
--- a/include/asm-s390/atomic.h
+++ b/include/asm-s390/atomic.h
@@ -75,6 +75,8 @@
__CS_LOOP(v, mask, "or");
}
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
static __inline__ int atomic_cmpxchg(atomic_t *v, int old, int new)
{
__asm__ __volatile__(" cs %0,%3,0(%2)\n"