forked from Minki/linux
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
151 lines
3.3 KiB
C
151 lines
3.3 KiB
C
/* $Id: atomic.h,v 1.3 2001/07/25 16:15:19 bjornw Exp $ */
|
|
|
|
#ifndef __ASM_CRIS_ATOMIC__
|
|
#define __ASM_CRIS_ATOMIC__
|
|
|
|
#include <asm/system.h>
|
|
|
|
/*
|
|
* Atomic operations that C can't guarantee us. Useful for
|
|
* resource counting etc..
|
|
*/
|
|
|
|
/*
|
|
* Make sure gcc doesn't try to be clever and move things around
|
|
* on us. We need to use _exactly_ the address the user gave us,
|
|
* not some alias that contains the same information.
|
|
*/
|
|
|
|
#define __atomic_fool_gcc(x) (*(struct { int a[100]; } *)x)
|
|
|
|
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))
|
|
|
|
/* These should be written in asm but we do it in C for now. */
|
|
|
|
extern __inline__ void atomic_add(int i, volatile atomic_t *v)
|
|
{
|
|
unsigned long flags;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
v->counter += i;
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
extern __inline__ void atomic_sub(int i, volatile atomic_t *v)
|
|
{
|
|
unsigned long flags;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
v->counter -= i;
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
extern __inline__ int atomic_add_return(int i, volatile atomic_t *v)
|
|
{
|
|
unsigned long flags;
|
|
int retval;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
retval = (v->counter += i);
|
|
local_irq_restore(flags);
|
|
return retval;
|
|
}
|
|
|
|
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
|
|
|
|
extern __inline__ int atomic_sub_return(int i, volatile atomic_t *v)
|
|
{
|
|
unsigned long flags;
|
|
int retval;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
retval = (v->counter -= i);
|
|
local_irq_restore(flags);
|
|
return retval;
|
|
}
|
|
|
|
extern __inline__ int atomic_sub_and_test(int i, volatile atomic_t *v)
|
|
{
|
|
int retval;
|
|
unsigned long flags;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
retval = (v->counter -= i) == 0;
|
|
local_irq_restore(flags);
|
|
return retval;
|
|
}
|
|
|
|
extern __inline__ void atomic_inc(volatile atomic_t *v)
|
|
{
|
|
unsigned long flags;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
(v->counter)++;
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
extern __inline__ void atomic_dec(volatile atomic_t *v)
|
|
{
|
|
unsigned long flags;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
(v->counter)--;
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
extern __inline__ int atomic_inc_return(volatile atomic_t *v)
|
|
{
|
|
unsigned long flags;
|
|
int retval;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
retval = (v->counter)++;
|
|
local_irq_restore(flags);
|
|
return retval;
|
|
}
|
|
|
|
extern __inline__ int atomic_dec_return(volatile atomic_t *v)
|
|
{
|
|
unsigned long flags;
|
|
int retval;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
retval = (v->counter)--;
|
|
local_irq_restore(flags);
|
|
return retval;
|
|
}
|
|
extern __inline__ int atomic_dec_and_test(volatile atomic_t *v)
|
|
{
|
|
int retval;
|
|
unsigned long flags;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
retval = --(v->counter) == 0;
|
|
local_irq_restore(flags);
|
|
return retval;
|
|
}
|
|
|
|
extern __inline__ int atomic_inc_and_test(volatile atomic_t *v)
|
|
{
|
|
int retval;
|
|
unsigned long flags;
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
retval = ++(v->counter) == 0;
|
|
local_irq_restore(flags);
|
|
return retval;
|
|
}
|
|
|
|
/* 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()
|
|
|
|
#endif
|