[mirror_ubuntu-artful-kernel.git] / tools / arch / powerpc / include / asm / barrier.h

/*
 * Copied from the kernel sources:
 *
 * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
 */
#ifndef _TOOLS_LINUX_ASM_POWERPC_BARRIER_H
#define _TOOLS_LINUX_ASM_POWERPC_BARRIER_H

/*
 * Memory barrier.
 * The sync instruction guarantees that all memory accesses initiated
 * by this processor have been performed (with respect to all other
 * mechanisms that access memory).  The eieio instruction is a barrier
 * providing an ordering (separately) for (a) cacheable stores and (b)
 * loads and stores to non-cacheable memory (e.g. I/O devices).
 *
 * mb() prevents loads and stores being reordered across this point.
 * rmb() prevents loads being reordered across this point.
 * wmb() prevents stores being reordered across this point.
 *
 * *mb() variants without smp_ prefix must order all types of memory
 * operations with one another. sync is the only instruction sufficient
 * to do this.
 */
#define mb()   __asm__ __volatile__ ("sync" : : : "memory")
#define rmb()  __asm__ __volatile__ ("sync" : : : "memory")
#define wmb()  __asm__ __volatile__ ("sync" : : : "memory")

#endif /* _TOOLS_LINUX_ASM_POWERPC_BARRIER_H */
Commit	Line	Data
e43a19c9 ACM	1	/*
	2	* Copied from the kernel sources:
	3	*
	4	* Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
	5	*/
	6	#ifndef _TOOLS_LINUX_ASM_POWERPC_BARRIER_H
	7	#define _TOOLS_LINUX_ASM_POWERPC_BARRIER_H
	8
	9	/*
	10	* Memory barrier.
	11	* The sync instruction guarantees that all memory accesses initiated
	12	* by this processor have been performed (with respect to all other
	13	* mechanisms that access memory). The eieio instruction is a barrier
	14	* providing an ordering (separately) for (a) cacheable stores and (b)
	15	* loads and stores to non-cacheable memory (e.g. I/O devices).
	16	*
	17	* mb() prevents loads and stores being reordered across this point.
	18	* rmb() prevents loads being reordered across this point.
	19	* wmb() prevents stores being reordered across this point.
	20	*
	21	* *mb() variants without smp_ prefix must order all types of memory
	22	* operations with one another. sync is the only instruction sufficient
	23	* to do this.
	24	*/
	25	#define mb() __asm__ __volatile__ ("sync" : : : "memory")
	26	#define rmb() __asm__ __volatile__ ("sync" : : : "memory")
	27	#define wmb() __asm__ __volatile__ ("sync" : : : "memory")
	28
	29	#endif /* _TOOLS_LINUX_ASM_POWERPC_BARRIER_H */