forked from Minki/linux
f3d46f9d31
In preparation for removing volatile from the atomic_t definition, this patch adds a volatile cast to all the atomic read functions. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
75 lines
2.0 KiB
C
75 lines
2.0 KiB
C
#ifndef __ASM_SH_ATOMIC_H
|
|
#define __ASM_SH_ATOMIC_H
|
|
|
|
/*
|
|
* Atomic operations that C can't guarantee us. Useful for
|
|
* resource counting etc..
|
|
*
|
|
*/
|
|
|
|
#include <linux/compiler.h>
|
|
#include <linux/types.h>
|
|
#include <asm/system.h>
|
|
|
|
#define ATOMIC_INIT(i) ( (atomic_t) { (i) } )
|
|
|
|
#define atomic_read(v) (*(volatile int *)&(v)->counter)
|
|
#define atomic_set(v,i) ((v)->counter = (i))
|
|
|
|
#if defined(CONFIG_GUSA_RB)
|
|
#include <asm/atomic-grb.h>
|
|
#elif defined(CONFIG_CPU_SH4A)
|
|
#include <asm/atomic-llsc.h>
|
|
#else
|
|
#include <asm/atomic-irq.h>
|
|
#endif
|
|
|
|
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
|
|
#define atomic_dec_return(v) atomic_sub_return(1, (v))
|
|
#define atomic_inc_return(v) atomic_add_return(1, (v))
|
|
#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)
|
|
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
|
|
|
|
#define atomic_inc(v) atomic_add(1, (v))
|
|
#define atomic_dec(v) atomic_sub(1, (v))
|
|
|
|
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
|
|
#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
|
|
|
|
/**
|
|
* atomic_add_unless - add unless the number is a given value
|
|
* @v: pointer of type atomic_t
|
|
* @a: the amount to add to v...
|
|
* @u: ...unless v is equal to u.
|
|
*
|
|
* Atomically adds @a to @v, so long as it was not @u.
|
|
* Returns non-zero if @v was not @u, and zero otherwise.
|
|
*/
|
|
static inline int atomic_add_unless(atomic_t *v, int a, int u)
|
|
{
|
|
int c, old;
|
|
c = atomic_read(v);
|
|
for (;;) {
|
|
if (unlikely(c == (u)))
|
|
break;
|
|
old = atomic_cmpxchg((v), c, c + (a));
|
|
if (likely(old == c))
|
|
break;
|
|
c = old;
|
|
}
|
|
|
|
return c != (u);
|
|
}
|
|
|
|
#define smp_mb__before_atomic_dec() smp_mb()
|
|
#define smp_mb__after_atomic_dec() smp_mb()
|
|
#define smp_mb__before_atomic_inc() smp_mb()
|
|
#define smp_mb__after_atomic_inc() smp_mb()
|
|
|
|
#include <asm-generic/atomic-long.h>
|
|
#include <asm-generic/atomic64.h>
|
|
|
|
#endif /* __ASM_SH_ATOMIC_H */
|