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#ifndef __ASM_SH64_ATOMIC_H
#define __ASM_SH64_ATOMIC_H
/*
* 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.
*
* include/asm-sh64/atomic.h
*
* Copyright (C) 2000, 2001 Paolo Alberelli
* Copyright (C) 2003 Paul Mundt
*
*/
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*
*/
typedef struct { volatile int counter; } atomic_t;
#define ATOMIC_INIT(i) ( (atomic_t) { (i) } )
#define atomic_read(v) ((v)->counter)
#define atomic_set(v,i) ((v)->counter = (i))
#include <asm/system.h>
/*
* To get proper branch prediction for the main line, we must branch
* forward to code at the end of this object's .text section, then
* branch back to restart the operation.
*/
static __inline__ void atomic_add(int i, atomic_t * v)
{
unsigned long flags;
local_irq_save(flags);
*(long *)v += i;
local_irq_restore(flags);
}
static __inline__ void atomic_sub(int i, atomic_t *v)
{
unsigned long flags;
local_irq_save(flags);
*(long *)v -= i;
local_irq_restore(flags);
}
static __inline__ int atomic_add_return(int i, atomic_t * v)
{
unsigned long temp, flags;
local_irq_save(flags);
temp = *(long *)v;
temp += i;
*(long *)v = temp;
local_irq_restore(flags);
return temp;
}
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
static __inline__ int atomic_sub_return(int i, atomic_t * v)
{
unsigned long temp, flags;
local_irq_save(flags);
temp = *(long *)v;
temp -= i;
*(long *)v = temp;
local_irq_restore(flags);
return temp;
}
#define atomic_dec_return(v) atomic_sub_return(1,(v))
#define atomic_inc_return(v) atomic_add_return(1,(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_inc(v) atomic_add(1,(v))
#define atomic_dec(v) atomic_sub(1,(v))
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)
static __inline__ void atomic_clear_mask(unsigned int mask, atomic_t *v)
{
unsigned long flags;
local_irq_save(flags);
*(long *)v &= ~mask;
local_irq_restore(flags);
}
static __inline__ void atomic_set_mask(unsigned int mask, atomic_t *v)
{
unsigned long flags;
local_irq_save(flags);
*(long *)v |= mask;
local_irq_restore(flags);
}
/* Atomic operations are already serializing on SH */
#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 /* __ASM_SH64_ATOMIC_H */
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