svn commit: r260610 - head/sys/powerpc/include

[Andreas Tobler]

Author: andreast
Date: Mon Jan 13 22:21:29 2014
New Revision: 260610
URL: http://svnweb.freebsd.org/changeset/base/260610

Log:
  Described in the man page but not implemented. Here it comes,
  atomic_swap_32/64. The latter only for powerpc64.
  
  MFC after:	1 month

Modified:
  head/sys/powerpc/include/atomic.h

Modified: head/sys/powerpc/include/atomic.h
==============================================================================
--- head/sys/powerpc/include/atomic.h	Mon Jan 13 22:15:57 2014	(r260609)
+++ head/sys/powerpc/include/atomic.h	Mon Jan 13 22:21:29 2014	(r260610)
@@ -684,10 +684,47 @@ atomic_fetchadd_long(volatile u_long *p,
 	return (value);
 }
 
+static __inline u_int
+atomic_swap_32(volatile u_int *p, u_int v)
+{
+	u_int prev;
+
+	__asm __volatile(
+	"1:	lwarx	%0,0,%2\n"
+	"	stwcx.	%3,0,%2\n"
+	"	bne-	1b\n"
+	: "=&r" (prev), "+m" (*(volatile u_int *)p)
+	: "r" (p), "r" (v)
+	: "cc", "memory");
+
+	return (prev);
+}
+
+#ifdef __powerpc64__
+static __inline u_long
+atomic_swap_64(volatile u_long *p, u_long v)
+{
+	u_long prev;
+
+	__asm __volatile(
+	"1:	ldarx	%0,0,%2\n"
+	"	stdcx.	%3,0,%2\n"
+	"	bne-	1b\n"
+	: "=&r" (prev), "+m" (*(volatile u_long *)p)
+	: "r" (p), "r" (v)
+	: "cc", "memory");
+
+	return (prev);
+}
+#endif
+
 #define	atomic_fetchadd_32	atomic_fetchadd_int
+#define	atomic_swap_int		atomic_swap_32
 
 #ifdef __powerpc64__
 #define	atomic_fetchadd_64	atomic_fetchadd_long
+#define	atomic_swap_long	atomic_swap_64
+#define	atomic_swap_ptr		atomic_swap_64
 #endif
 
 #undef __ATOMIC_REL