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#ifndef __ASM_METAG_ATOMIC_LOCK1_H
#define __ASM_METAG_ATOMIC_LOCK1_H
#define ATOMIC_INIT(i) { (i) }
#include <linux/compiler.h>
#include <asm/barrier.h>
#include <asm/global_lock.h>
static inline int atomic_read(const atomic_t *v)
{
return (v)->counter;
}
/*
* atomic_set needs to be take the lock to protect atomic_add_unless from a
* possible race, as it reads the counter twice:
*
* CPU0 CPU1
* atomic_add_unless(1, 0)
* ret = v->counter (non-zero)
* if (ret != u) v->counter = 0
* v->counter += 1 (counter set to 1)
*
* Making atomic_set take the lock ensures that ordering and logical
* consistency is preserved.
*/
static inline int atomic_set(atomic_t *v, int i)
{
unsigned long flags;
__global_lock1(flags);
fence();
v->counter = i;
__global_unlock1(flags);
return i;
}
static inline void atomic_add(int i, atomic_t *v)
{
unsigned long flags;
__global_lock1(flags);
fence();
v->counter += i;
__global_unlock1(flags);
}
static inline void atomic_sub(int i, atomic_t *v)
{
unsigned long flags;
__global_lock1(flags);
fence();
v->counter -= i;
__global_unlock1(flags);
}
static inline int atomic_add_return(int i, atomic_t *v)
{
unsigned long result;
unsigned long flags;
__global_lock1(flags);
result = v->counter;
result += i;
fence();
v->counter = result;
__global_unlock1(flags);
return result;
}
static inline int atomic_sub_return(int i, atomic_t *v)
{
unsigned long result;
unsigned long flags;
__global_lock1(flags);
result = v->counter;
result -= i;
fence();
v->counter = result;
__global_unlock1(flags);
return result;
}
static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
{
unsigned long flags;
__global_lock1(flags);
fence();
v->counter &= ~mask;
__global_unlock1(flags);
}
static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
{
unsigned long flags;
__global_lock1(flags);
fence();
v->counter |= mask;
__global_unlock1(flags);
}
static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
int ret;
unsigned long flags;
__global_lock1(flags);
ret = v->counter;
if (ret == old) {
fence();
v->counter = new;
}
__global_unlock1(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;
__global_lock1(flags);
ret = v->counter;
if (ret != u) {
fence();
v->counter += a;
}
__global_unlock1(flags);
return ret;
}
static inline int atomic_sub_if_positive(int i, atomic_t *v)
{
int ret;
unsigned long flags;
__global_lock1(flags);
ret = v->counter - 1;
if (ret >= 0) {
fence();
v->counter = ret;
}
__global_unlock1(flags);
return ret;
}
#endif /* __ASM_METAG_ATOMIC_LOCK1_H */