82 lines
1.9 KiB
C
82 lines
1.9 KiB
C
/*
|
|
* Generic barrier definitions, originally 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__
|
|
|
|
#include <linux/compiler.h>
|
|
|
|
#ifndef nop
|
|
#define nop() asm volatile ("nop")
|
|
#endif
|
|
|
|
/*
|
|
* Force strict CPU ordering. And yes, this is required on UP too when we're
|
|
* talking to devices.
|
|
*
|
|
* Fall back to compiler barriers if nothing better is provided.
|
|
*/
|
|
|
|
#ifndef mb
|
|
#define mb() barrier()
|
|
#endif
|
|
|
|
#ifndef rmb
|
|
#define rmb() mb()
|
|
#endif
|
|
|
|
#ifndef wmb
|
|
#define wmb() mb()
|
|
#endif
|
|
|
|
#ifndef read_barrier_depends
|
|
#define read_barrier_depends() do { } while (0)
|
|
#endif
|
|
|
|
#ifdef CONFIG_SMP
|
|
#define smp_mb() mb()
|
|
#define smp_rmb() rmb()
|
|
#define smp_wmb() wmb()
|
|
#define smp_read_barrier_depends() read_barrier_depends()
|
|
#else
|
|
#define smp_mb() barrier()
|
|
#define smp_rmb() barrier()
|
|
#define smp_wmb() barrier()
|
|
#define smp_read_barrier_depends() do { } while (0)
|
|
#endif
|
|
|
|
#ifndef set_mb
|
|
#define set_mb(var, value) do { (var) = (value); mb(); } while (0)
|
|
#endif
|
|
|
|
#define smp_store_release(p, v) \
|
|
do { \
|
|
compiletime_assert_atomic_type(*p); \
|
|
smp_mb(); \
|
|
ACCESS_ONCE(*p) = (v); \
|
|
} while (0)
|
|
|
|
#define smp_load_acquire(p) \
|
|
({ \
|
|
typeof(*p) ___p1 = ACCESS_ONCE(*p); \
|
|
compiletime_assert_atomic_type(*p); \
|
|
smp_mb(); \
|
|
___p1; \
|
|
})
|
|
|
|
#endif /* !__ASSEMBLY__ */
|
|
#endif /* __ASM_GENERIC_BARRIER_H */
|