linux/arch/sparc/lib/atomic32.c
Ingo Molnar a9f6a0dd54 [PATCH] more SPIN_LOCK_UNLOCKED -> DEFINE_SPINLOCK conversions
This converts the final 20 DEFINE_SPINLOCK holdouts.  (another 580 places
are already using DEFINE_SPINLOCK).  Build tested on x86.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 14:03:48 -07:00

54 lines
1.0 KiB
C

/*
* atomic32.c: 32-bit atomic_t implementation
*
* Copyright (C) 2004 Keith M Wesolowski
*
* Based on asm-parisc/atomic.h Copyright (C) 2000 Philipp Rumpf
*/
#include <asm/atomic.h>
#include <linux/spinlock.h>
#include <linux/module.h>
#ifdef CONFIG_SMP
#define ATOMIC_HASH_SIZE 4
#define ATOMIC_HASH(a) (&__atomic_hash[(((unsigned long)a)>>8) & (ATOMIC_HASH_SIZE-1)])
spinlock_t __atomic_hash[ATOMIC_HASH_SIZE] = {
[0 ... (ATOMIC_HASH_SIZE-1)] = SPIN_LOCK_UNLOCKED
};
#else /* SMP */
static DEFINE_SPINLOCK(dummy);
#define ATOMIC_HASH_SIZE 1
#define ATOMIC_HASH(a) (&dummy)
#endif /* SMP */
int __atomic_add_return(int i, atomic_t *v)
{
int ret;
unsigned long flags;
spin_lock_irqsave(ATOMIC_HASH(v), flags);
ret = (v->counter += i);
spin_unlock_irqrestore(ATOMIC_HASH(v), flags);
return ret;
}
void atomic_set(atomic_t *v, int i)
{
unsigned long flags;
spin_lock_irqsave(ATOMIC_HASH(v), flags);
v->counter = i;
spin_unlock_irqrestore(ATOMIC_HASH(v), flags);
}
EXPORT_SYMBOL(__atomic_add_return);
EXPORT_SYMBOL(atomic_set);