alistair23-linux/include/asm-sparc64/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

101 lines
3.2 KiB
C

/* $Id: atomic.h,v 1.22 2001/07/11 23:56:07 davem Exp $
* atomic.h: Thankfully the V9 is at least reasonable for this
* stuff.
*
* Copyright (C) 1996, 1997, 2000 David S. Miller (davem@redhat.com)
*/
#ifndef __ARCH_SPARC64_ATOMIC__
#define __ARCH_SPARC64_ATOMIC__
#include <linux/config.h>
#include <linux/types.h>
typedef struct { volatile int counter; } atomic_t;
typedef struct { volatile __s64 counter; } atomic64_t;
#define ATOMIC_INIT(i) { (i) }
#define ATOMIC64_INIT(i) { (i) }
#define atomic_read(v) ((v)->counter)
#define atomic64_read(v) ((v)->counter)
#define atomic_set(v, i) (((v)->counter) = i)
#define atomic64_set(v, i) (((v)->counter) = i)
extern void atomic_add(int, atomic_t *);
extern void atomic64_add(int, atomic64_t *);
extern void atomic_sub(int, atomic_t *);
extern void atomic64_sub(int, atomic64_t *);
extern int atomic_add_ret(int, atomic_t *);
extern int atomic64_add_ret(int, atomic64_t *);
extern int atomic_sub_ret(int, atomic_t *);
extern int atomic64_sub_ret(int, atomic64_t *);
#define atomic_dec_return(v) atomic_sub_ret(1, v)
#define atomic64_dec_return(v) atomic64_sub_ret(1, v)
#define atomic_inc_return(v) atomic_add_ret(1, v)
#define atomic64_inc_return(v) atomic64_add_ret(1, v)
#define atomic_sub_return(i, v) atomic_sub_ret(i, v)
#define atomic64_sub_return(i, v) atomic64_sub_ret(i, v)
#define atomic_add_return(i, v) atomic_add_ret(i, v)
#define atomic64_add_return(i, v) atomic64_add_ret(i, 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 atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
#define atomic_sub_and_test(i, v) (atomic_sub_ret(i, v) == 0)
#define atomic64_sub_and_test(i, v) (atomic64_sub_ret(i, v) == 0)
#define atomic_dec_and_test(v) (atomic_sub_ret(1, v) == 0)
#define atomic64_dec_and_test(v) (atomic64_sub_ret(1, v) == 0)
#define atomic_inc(v) atomic_add(1, v)
#define atomic64_inc(v) atomic64_add(1, v)
#define atomic_dec(v) atomic_sub(1, v)
#define atomic64_dec(v) atomic64_sub(1, v)
#define atomic_add_negative(i, v) (atomic_add_ret(i, v) < 0)
#define atomic64_add_negative(i, v) (atomic64_add_ret(i, v) < 0)
#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
#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)
/* Atomic operations are already serializing */
#ifdef CONFIG_SMP
#define smp_mb__before_atomic_dec() membar_storeload_loadload();
#define smp_mb__after_atomic_dec() membar_storeload_storestore();
#define smp_mb__before_atomic_inc() membar_storeload_loadload();
#define smp_mb__after_atomic_inc() membar_storeload_storestore();
#else
#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
#include <asm-generic/atomic.h>
#endif /* !(__ARCH_SPARC64_ATOMIC__) */