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-rw-r--r--include/asm-parisc/atomic.h19
1 files changed, 19 insertions, 0 deletions
diff --git a/include/asm-parisc/atomic.h b/include/asm-parisc/atomic.h
index 52c9a45b5f8..983e9a2b604 100644
--- a/include/asm-parisc/atomic.h
+++ b/include/asm-parisc/atomic.h
@@ -166,6 +166,25 @@ static __inline__ int atomic_read(const atomic_t *v)
/* exported interface */
#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
+/**
+ * atomic_add_unless - add unless the number is a given value
+ * @v: pointer of type atomic_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, so long as it was not @u.
+ * Returns non-zero if @v was not @u, and zero otherwise.
+ */
+#define atomic_add_unless(v, a, u) \
+({ \
+ int c, old; \
+ c = atomic_read(v); \
+ while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
+ c = old; \
+ c != (u); \
+})
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
#define atomic_add(i,v) ((void)(__atomic_add_return( ((int)i),(v))))
#define atomic_sub(i,v) ((void)(__atomic_add_return(-((int)i),(v))))
#define atomic_inc(v) ((void)(__atomic_add_return( 1,(v))))