tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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 */