diff options
Diffstat (limited to 'arch/sparc/lib/atomic32.c')
-rw-r--r-- | arch/sparc/lib/atomic32.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/arch/sparc/lib/atomic32.c b/arch/sparc/lib/atomic32.c new file mode 100644 index 000000000000..19724c5800a7 --- /dev/null +++ b/arch/sparc/lib/atomic32.c @@ -0,0 +1,53 @@ +/* + * 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 spinlock_t dummy = SPIN_LOCK_UNLOCKED; +#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); + |