linux/include/asm-v850/atomic.h

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/*
* include/asm-v850/atomic.h -- Atomic operations
*
* Copyright (C) 2001,02 NEC Corporation
* Copyright (C) 2001,02 Miles Bader <miles@gnu.org>
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file COPYING in the main directory of this
* archive for more details.
*
* Written by Miles Bader <miles@gnu.org>
*/
#ifndef __V850_ATOMIC_H__
#define __V850_ATOMIC_H__
#include <linux/config.h>
#include <asm/system.h>
#ifdef CONFIG_SMP
#error SMP not supported
#endif
typedef struct { int counter; } atomic_t;
#define ATOMIC_INIT(i) { (i) }
#ifdef __KERNEL__
#define atomic_read(v) ((v)->counter)
#define atomic_set(v,i) (((v)->counter) = (i))
static inline int atomic_add_return (int i, volatile atomic_t *v)
{
unsigned long flags;
int res;
local_irq_save (flags);
res = v->counter + i;
v->counter = res;
local_irq_restore (flags);
return res;
}
static __inline__ int atomic_sub_return (int i, volatile atomic_t *v)
{
unsigned long flags;
int res;
local_irq_save (flags);
res = v->counter - i;
v->counter = res;
local_irq_restore (flags);
return res;
}
static __inline__ void atomic_clear_mask (unsigned long mask, unsigned long *addr)
{
unsigned long flags;
local_irq_save (flags);
*addr &= ~mask;
local_irq_restore (flags);
}
#endif
#define atomic_add(i, v) atomic_add_return ((i), (v))
#define atomic_sub(i, v) atomic_sub_return ((i), (v))
#define atomic_dec_return(v) atomic_sub_return (1, (v))
#define atomic_inc_return(v) atomic_add_return (1, (v))
#define atomic_inc(v) atomic_inc_return (v)
#define atomic_dec(v) atomic_dec_return (v)
/*
* atomic_inc_and_test - increment and test
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1
* and returns true if the result is zero, or false for all
* other cases.
*/
#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
#define atomic_sub_and_test(i,v) (atomic_sub_return ((i), (v)) == 0)
#define atomic_dec_and_test(v) (atomic_sub_return (1, (v)) == 0)
#define atomic_add_negative(i,v) (atomic_add_return ((i), (v)) < 0)
static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
int ret;
unsigned long flags;
local_irq_save(flags);
ret = v->counter;
if (likely(ret == old))
v->counter = new;
local_irq_restore(flags);
return ret;
}
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
static inline int atomic_add_unless(atomic_t *v, int a, int u)
{
int ret;
unsigned long flags;
local_irq_save(flags);
ret = v->counter;
if (ret != u)
v->counter += a;
local_irq_restore(flags);
return ret != u;
}
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
/* Atomic operations are already serializing on ARM */
#define smp_mb__before_atomic_dec() barrier()
#define smp_mb__after_atomic_dec() barrier()
#define smp_mb__before_atomic_inc() barrier()
#define smp_mb__after_atomic_inc() barrier()
#include <asm-generic/atomic.h>
#endif /* __V850_ATOMIC_H__ */