arch,m32r: Convert smp_mb__*()

M32r uses asm-generic/barrier.h and its smp_mb() is barrier();
therefore we can use the generic versions which default to smp_mb().

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-wh6xljltyvmpy9t0bc80k1fy@git.kernel.org
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-m32r-ja@ml.linux-m32r.org
Cc: linux-m32r@ml.linux-m32r.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/m32r/include/asm/atomic.h

@@ -13,6 +13,7 @@
 #include <asm/assembler.h>
 #include <asm/cmpxchg.h>
 #include <asm/dcache_clear.h>
+#include <asm/barrier.h>
 
 /*
  * Atomic operations that C can't guarantee us.  Useful for
@@ -308,10 +309,4 @@ static __inline__ void atomic_set_mask(unsigned long  mask, atomic_t *addr)
 	local_irq_restore(flags);
 }
 
-/* Atomic operations are already serializing on m32r */
-#define smp_mb__before_atomic_dec()	barrier()
-#define smp_mb__after_atomic_dec()	barrier()
-#define smp_mb__before_atomic_inc()	barrier()
-#define smp_mb__after_atomic_inc()	barrier()
-
 #endif	/* _ASM_M32R_ATOMIC_H */

arch/m32r/include/asm/bitops.h

@@ -21,6 +21,7 @@
 #include <asm/byteorder.h>
 #include <asm/dcache_clear.h>
 #include <asm/types.h>
+#include <asm/barrier.h>
 
 /*
  * These have to be done with inline assembly: that way the bit-setting
@@ -73,7 +74,7 @@ static __inline__ void set_bit(int nr, volatile void * addr)
  *
  * clear_bit() is atomic and may not be reordered.  However, it does
  * not contain a memory barrier, so if it is used for locking purposes,
- * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
+ * you should call smp_mb__before_atomic() and/or smp_mb__after_atomic()
  * in order to ensure changes are visible on other processors.
  */
 static __inline__ void clear_bit(int nr, volatile void * addr)
@@ -103,9 +104,6 @@ static __inline__ void clear_bit(int nr, volatile void * addr)
 	local_irq_restore(flags);
 }
 
-#define smp_mb__before_clear_bit()	barrier()
-#define smp_mb__after_clear_bit()	barrier()
-
 /**
  * change_bit - Toggle a bit in memory
  * @nr: Bit to clear