Merge git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc

* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (78 commits)
  [PATCH] powerpc: Add FSL SEC node to documentation
  [PATCH] macintosh: tidy-up driver_register() return values
  [PATCH] powerpc: tidy-up of_register_driver()/driver_register() return values
  [PATCH] powerpc: via-pmu warning fix
  [PATCH] macintosh: cleanup the use of i2c headers
  [PATCH] powerpc: dont allow old RTC to be selected
  [PATCH] powerpc: make powerbook_sleep_grackle static
  [PATCH] powerpc: Fix warning in add_memory
  [PATCH] powerpc: update mailing list addresses
  [PATCH] powerpc: Remove calculation of io hole
  [PATCH] powerpc: iseries: Add bootargs to /chosen
  [PATCH] powerpc: iseries: Add /system-id, /model and /compatible
  [PATCH] powerpc: Add strne2a() to convert a string from EBCDIC to ASCII
  [PATCH] powerpc: iseries: Make more stuff static in platforms/iseries/mf.c
  [PATCH] powerpc: iseries: Remove pointless iSeries_(restart|power_off|halt)
  [PATCH] powerpc: iseries: mf related cleanups
  [PATCH] powerpc: Replace platform_is_lpar() with a firmware feature
  [PATCH] powerpc: trivial: Cleanup whitespace in cputable.h
  [PATCH] powerpc: Remove unused iommu_off logic from pSeries_init_early()
  [PATCH] powerpc: Unconfuse htab_bolt_mapping() callers
  ...

1 files changed, 24 insertions, 14 deletions

diff --git a/include/asm-powerpc/atomic.h b/include/asm-powerpc/atomic.h
index 147a38dcc766..bb3c0ab7e667 100644
--- a/include/asm-powerpc/atomic.h
+++ b/include/asm-powerpc/atomic.h
@@ -8,6 +8,7 @@
 typedef struct { volatile int counter; } atomic_t;
 
 #ifdef __KERNEL__
+#include <linux/compiler.h>
 #include <asm/synch.h>
 #include <asm/asm-compat.h>
 
@@ -176,20 +177,29 @@ static __inline__ int atomic_dec_return(atomic_t *v)
  * 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);				\
-	for (;;) {					\
-		if (unlikely(c == (u)))			\
-			break;				\
-		old = atomic_cmpxchg((v), c, c + (a));	\
-		if (likely(old == c))			\
-			break;				\
-		c = old;				\
-	}						\
-	c != (u);					\
-})
+static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+{
+	int t;
+
+	__asm__ __volatile__ (
+	LWSYNC_ON_SMP
+"1:	lwarx	%0,0,%1		# atomic_add_unless\n\
+	cmpw	0,%0,%3 \n\
+	beq-	2f \n\
+	add	%0,%2,%0 \n"
+	PPC405_ERR77(0,%2)
+"	stwcx.	%0,0,%1 \n\
+	bne-	1b \n"
+	ISYNC_ON_SMP
+"	subf	%0,%2,%0 \n\
+2:"
+	: "=&r" (t)
+	: "r" (&v->counter), "r" (a), "r" (u)
+	: "cc", "memory");
+
+	return t != u;
+}
+
 #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
 
 #define atomic_sub_and_test(a, v)	(atomic_sub_return((a), (v)) == 0)