mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-29 23:53:32 +00:00
885df91ca3
Create asm-generic/barrier.h and move the barrier definitions from asm-generic/system.h to it. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
50 lines
1.4 KiB
C
50 lines
1.4 KiB
C
/* Generic barrier definitions, based on MN10300 definitions.
|
|
*
|
|
* It should be possible to use these on really simple architectures,
|
|
* but it serves more as a starting point for new ports.
|
|
*
|
|
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public Licence
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the Licence, or (at your option) any later version.
|
|
*/
|
|
#ifndef __ASM_GENERIC_BARRIER_H
|
|
#define __ASM_GENERIC_BARRIER_H
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#define nop() asm volatile ("nop")
|
|
|
|
/*
|
|
* Force strict CPU ordering.
|
|
* And yes, this is required on UP too when we're talking
|
|
* to devices.
|
|
*
|
|
* This implementation only contains a compiler barrier.
|
|
*/
|
|
|
|
#define mb() asm volatile ("": : :"memory")
|
|
#define rmb() mb()
|
|
#define wmb() asm volatile ("": : :"memory")
|
|
|
|
#ifdef CONFIG_SMP
|
|
#define smp_mb() mb()
|
|
#define smp_rmb() rmb()
|
|
#define smp_wmb() wmb()
|
|
#else
|
|
#define smp_mb() barrier()
|
|
#define smp_rmb() barrier()
|
|
#define smp_wmb() barrier()
|
|
#endif
|
|
|
|
#define set_mb(var, value) do { var = value; mb(); } while (0)
|
|
#define set_wmb(var, value) do { var = value; wmb(); } while (0)
|
|
|
|
#define read_barrier_depends() do {} while (0)
|
|
#define smp_read_barrier_depends() do {} while (0)
|
|
|
|
#endif /* !__ASSEMBLY__ */
|
|
#endif /* __ASM_GENERIC_BARRIER_H */
|