linux/include/asm-cris/atomic.h
Christoph Lameter d3cb487149 [PATCH] atomic_long_t & include/asm-generic/atomic.h V2
Several counters already have the need to use 64 atomic variables on 64 bit
platforms (see mm_counter_t in sched.h).  We have to do ugly ifdefs to fall
back to 32 bit atomic on 32 bit platforms.

The VM statistics patch that I am working on will also make more extensive
use of atomic64.

This patch introduces a new type atomic_long_t by providing definitions in
asm-generic/atomic.h that works similar to the c "long" type.  Its 32 bits
on 32 bit platforms and 64 bits on 64 bit platforms.

Also cleans up the determination of the mm_counter_t in sched.h.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:29 -08:00

160 lines
3.4 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>
#include <asm/arch/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) { (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. */
static inline void atomic_add(int i, volatile atomic_t *v)
{
unsigned long flags;
cris_atomic_save(v, flags);
v->counter += i;
cris_atomic_restore(v, flags);
}
static inline void atomic_sub(int i, volatile atomic_t *v)
{
unsigned long flags;
cris_atomic_save(v, flags);
v->counter -= i;
cris_atomic_restore(v, flags);
}
static inline int atomic_add_return(int i, volatile atomic_t *v)
{
unsigned long flags;
int retval;
cris_atomic_save(v, flags);
retval = (v->counter += i);
cris_atomic_restore(v, flags);
return retval;
}
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
static inline int atomic_sub_return(int i, volatile atomic_t *v)
{
unsigned long flags;
int retval;
cris_atomic_save(v, flags);
retval = (v->counter -= i);
cris_atomic_restore(v, flags);
return retval;
}
static inline int atomic_sub_and_test(int i, volatile atomic_t *v)
{
int retval;
unsigned long flags;
cris_atomic_save(v, flags);
retval = (v->counter -= i) == 0;
cris_atomic_restore(v, flags);
return retval;
}
static inline void atomic_inc(volatile atomic_t *v)
{
unsigned long flags;
cris_atomic_save(v, flags);
(v->counter)++;
cris_atomic_restore(v, flags);
}
static inline void atomic_dec(volatile atomic_t *v)
{
unsigned long flags;
cris_atomic_save(v, flags);
(v->counter)--;
cris_atomic_restore(v, flags);
}
static inline int atomic_inc_return(volatile atomic_t *v)
{
unsigned long flags;
int retval;
cris_atomic_save(v, flags);
retval = (v->counter)++;
cris_atomic_restore(v, flags);
return retval;
}
static inline int atomic_dec_return(volatile atomic_t *v)
{
unsigned long flags;
int retval;
cris_atomic_save(v, flags);
retval = (v->counter)--;
cris_atomic_restore(v, flags);
return retval;
}
static inline int atomic_dec_and_test(volatile atomic_t *v)
{
int retval;
unsigned long flags;
cris_atomic_save(v, flags);
retval = --(v->counter) == 0;
cris_atomic_restore(v, flags);
return retval;
}
static inline int atomic_inc_and_test(volatile atomic_t *v)
{
int retval;
unsigned long flags;
cris_atomic_save(v, flags);
retval = ++(v->counter) == 0;
cris_atomic_restore(v, flags);
return retval;
}
static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
int ret;
unsigned long flags;
cris_atomic_save(v, flags);
ret = v->counter;
if (likely(ret == old))
v->counter = new;
cris_atomic_restore(v, flags);
return ret;
}
static inline int atomic_add_unless(atomic_t *v, int a, int u)
{
int ret;
unsigned long flags;
cris_atomic_save(v, flags);
ret = v->counter;
if (ret != u)
v->counter += a;
cris_atomic_restore(v, flags);
return ret != u;
}
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
/* 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()
#include <asm-generic/atomic.h>
#endif