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#ifndef __ASM_SH_ATOMIC_H
#define __ASM_SH_ATOMIC_H
/*
* 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;
save_and_cli(flags);
*(long *)v += i;
restore_flags(flags);
}
static __inline__ void atomic_sub(int i, atomic_t *v)
{
unsigned long flags;
save_and_cli(flags);
*(long *)v -= i;
restore_flags(flags);
}
static __inline__ int atomic_add_return(int i, atomic_t * v)
{
unsigned long temp, flags;
save_and_cli(flags);
temp = *(long *)v;
temp += i;
*(long *)v = temp;
restore_flags(flags);
return temp;
}
static __inline__ int atomic_sub_return(int i, atomic_t * v)
{
unsigned long temp, flags;
save_and_cli(flags);
temp = *(long *)v;
temp -= i;
*(long *)v = temp;
restore_flags(flags);
return temp;
}
#define atomic_dec_return(v) atomic_sub_return(1,(v))
#define atomic_inc_return(v) atomic_add_return(1,(v))
#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__ void atomic_clear_mask(unsigned int mask, atomic_t *v)
{
unsigned long flags;
save_and_cli(flags);
*(long *)v &= ~mask;
restore_flags(flags);
}
static __inline__ void atomic_set_mask(unsigned int mask, atomic_t *v)
{
unsigned long flags;
save_and_cli(flags);
*(long *)v |= mask;
restore_flags(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()
#endif /* __ASM_SH_ATOMIC_H */
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