svn commit: r198692 - head/sys/dev/drm

[Robert Noland]

Author: rnoland
Date: Fri Oct 30 16:59:58 2009
New Revision: 198692
URL: http://svn.freebsd.org/changeset/base/198692

Log:
  Use system specified memory barriers rather than rolling our own.

Modified:
  head/sys/dev/drm/drmP.h

Modified: head/sys/dev/drm/drmP.h
==============================================================================
--- head/sys/dev/drm/drmP.h	Fri Oct 30 16:55:31 2009	(r198691)
+++ head/sys/dev/drm/drmP.h	Fri Oct 30 16:59:58 2009	(r198692)
@@ -223,23 +223,9 @@ typedef u_int8_t u8;
  * DRM_WRITEMEMORYBARRIER() prevents reordering of writes.
  * DRM_MEMORYBARRIER() prevents reordering of reads and writes.
  */
-#if defined(__i386__)
-#define DRM_READMEMORYBARRIER()		__asm __volatile( \
-					"lock; addl $0,0(%%esp)" : : : "memory");
-#define DRM_WRITEMEMORYBARRIER()	__asm __volatile("" : : : "memory");
-#define DRM_MEMORYBARRIER()		__asm __volatile( \
-					"lock; addl $0,0(%%esp)" : : : "memory");
-#elif defined(__alpha__)
-#define DRM_READMEMORYBARRIER()		alpha_mb();
-#define DRM_WRITEMEMORYBARRIER()	alpha_wmb();
-#define DRM_MEMORYBARRIER()		alpha_mb();
-#elif defined(__amd64__)
-#define DRM_READMEMORYBARRIER()		__asm __volatile( \
-					"lock; addl $0,0(%%rsp)" : : : "memory");
-#define DRM_WRITEMEMORYBARRIER()	__asm __volatile("" : : : "memory");
-#define DRM_MEMORYBARRIER()		__asm __volatile( \
-					"lock; addl $0,0(%%rsp)" : : : "memory");
-#endif
+#define DRM_READMEMORYBARRIER()		rmb()
+#define DRM_WRITEMEMORYBARRIER()	wmb()
+#define DRM_MEMORYBARRIER()		mb()
 
 #define DRM_READ8(map, offset)						\
 	*(volatile u_int8_t *)(((vm_offset_t)(map)->handle) +		\