Viewing file:  atomic.h (3.03 KB) -rw-r--r--
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#ifndef __ARCH_BLACKFIN_ATOMIC__
#define __ARCH_BLACKFIN_ATOMIC__
#include <asm/system.h> /* local_irq_XXX() */
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*
* Generally we do not concern about SMP BFIN systems, so we don't have
* to deal with that.
*
* Tony Kou (tonyko@lineo.ca) Lineo Inc. 2001
*/
typedef struct {
int counter;
} atomic_t;
#define ATOMIC_INIT(i) { (i) }
#define atomic_read(v) ((v)->counter)
#define atomic_set(v, i) (((v)->counter) = i)
static __inline__ void atomic_add(int i, atomic_t * v)
{
long flags;
local_irq_save(flags);
v->counter += i;
local_irq_restore(flags);
}
static __inline__ void atomic_sub(int i, atomic_t * v)
{
long flags;
local_irq_save(flags);
v->counter -= i;
local_irq_restore(flags);
}
static inline int atomic_add_return(int i, atomic_t * v)
{
int __temp = 0;
long flags;
local_irq_save(flags);
v->counter += i;
__temp = v->counter;
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)
{
int __temp = 0;
long flags;
local_irq_save(flags);
v->counter -= i;
__temp = v->counter;
local_irq_restore(flags);
return __temp;
}
static __inline__ void atomic_inc(volatile atomic_t * v)
{
long flags;
local_irq_save(flags);
v->counter++;
local_irq_restore(flags);
}
#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
#define atomic_add_unless(v, a, u) \
({ \
int c, old; \
c = atomic_read(v); \
while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
c = old; \
c != (u); \
})
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
static __inline__ void atomic_dec(volatile atomic_t * v)
{
long flags;
local_irq_save(flags);
v->counter--;
local_irq_restore(flags);
}
static __inline__ void atomic_clear_mask(unsigned int mask, atomic_t * v)
{
long flags;
local_irq_save(flags);
v->counter &= ~mask;
local_irq_restore(flags);
}
static __inline__ void atomic_set_mask(unsigned int mask, atomic_t * v)
{
long flags;
local_irq_save(flags);
v->counter |= mask;
local_irq_restore(flags);
}
/* Atomic operations are already serializing */
#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()
#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)
#include <asm-generic/atomic.h>
#endif /* __ARCH_BLACKFIN_ATOMIC __ */
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