2 files changed, 36 insertions, 17 deletions
diff --git a/arch/alpha/include/asm/bitops.h b/arch/alpha/include/asm/bitops.h
index bafb1c1f0f..3e33621922 100644
--- a/arch/alpha/include/asm/bitops.h
+++ b/arch/alpha/include/asm/bitops.h
@@ -286,6 +286,26 @@ arch___test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
 #define arch_test_bit generic_test_bit
 #define arch_test_bit_acquire generic_test_bit_acquire
 
+static inline bool xor_unlock_is_negative_byte(unsigned long mask,
+		volatile unsigned long *p)
+{
+	unsigned long temp, old;
+
+	__asm__ __volatile__(
+	"1:	ldl_l %0,%4\n"
+	"	mov %0,%2\n"
+	"	xor %0,%3,%0\n"
+	"	stl_c %0,%1\n"
+	"	beq %0,2f\n"
+	".subsection 2\n"
+	"2:	br 1b\n"
+	".previous"
+	:"=&r" (temp), "=m" (*p), "=&r" (old)
+	:"Ir" (mask), "m" (*p));
+
+	return (old & BIT(7)) != 0;
+}
+
 /*
  * ffz = Find First Zero in word. Undefined if no zero exists,
  * so code should check against ~0UL first..
diff --git a/arch/alpha/include/asm/local.h b/arch/alpha/include/asm/local.h
index 0fcaad642c..88eb398947 100644
--- a/arch/alpha/include/asm/local.h
+++ b/arch/alpha/include/asm/local.h
@@ -65,28 +65,27 @@ static __inline__ bool local_try_cmpxchg(local_t *l, long *old, long new)
 #define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
 
 /**
- * local_add_unless - add unless the number is a given value
+ * local_add_unless - add unless the number is already a given value
  * @l: pointer of type local_t
  * @a: the amount to add to l...
  * @u: ...unless l is equal to u.
  *
- * Atomically adds @a to @l, so long as it was not @u.
- * Returns non-zero if @l was not @u, and zero otherwise.
+ * Atomically adds @a to @l, if @v was not already @u.
+ * Returns true if the addition was done.
  */
-#define local_add_unless(l, a, u)				\
-({								\
-	long c, old;						\
-	c = local_read(l);					\
-	for (;;) {						\
-		if (unlikely(c == (u)))				\
-			break;					\
-		old = local_cmpxchg((l), c, c + (a));	\
-		if (likely(old == c))				\
-			break;					\
-		c = old;					\
-	}							\
-	c != (u);						\
-})
+static __inline__ bool
+local_add_unless(local_t *l, long a, long u)
+{
+	long c = local_read(l);
+
+	do {
+		if (unlikely(c == u))
+			return false;
+	} while (!local_try_cmpxchg(l, &c, c + a));
+
+	return true;
+}
+
 #define local_inc_not_zero(l) local_add_unless((l), 1, 0)
 
 #define local_add_negative(a, l) (local_add_return((a), (l)) < 0)