diff options
Diffstat (limited to 'arch/sparc/lib/atomic32.c')
-rw-r--r-- | arch/sparc/lib/atomic32.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/sparc/lib/atomic32.c b/arch/sparc/lib/atomic32.c new file mode 100644 index 000000000..71cd65ab2 --- /dev/null +++ b/arch/sparc/lib/atomic32.c @@ -0,0 +1,166 @@ +/* + * atomic32.c: 32-bit atomic_t implementation + * + * Copyright (C) 2004 Keith M Wesolowski + * Copyright (C) 2007 Kyle McMartin + * + * Based on asm-parisc/atomic.h Copyright (C) 2000 Philipp Rumpf + */ + +#include <linux/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(__atomic_hash) +}; + +#else /* SMP */ + +static DEFINE_SPINLOCK(dummy); +#define ATOMIC_HASH_SIZE 1 +#define ATOMIC_HASH(a) (&dummy) + +#endif /* SMP */ + +#define ATOMIC_OP(op, cop) \ +int atomic_##op##_return(int i, atomic_t *v) \ +{ \ + int ret; \ + unsigned long flags; \ + spin_lock_irqsave(ATOMIC_HASH(v), flags); \ + \ + ret = (v->counter cop i); \ + \ + spin_unlock_irqrestore(ATOMIC_HASH(v), flags); \ + return ret; \ +} \ +EXPORT_SYMBOL(atomic_##op##_return); + +ATOMIC_OP(add, +=) + +#undef ATOMIC_OP + +int atomic_xchg(atomic_t *v, int new) +{ + int ret; + unsigned long flags; + + spin_lock_irqsave(ATOMIC_HASH(v), flags); + ret = v->counter; + v->counter = new; + spin_unlock_irqrestore(ATOMIC_HASH(v), flags); + return ret; +} +EXPORT_SYMBOL(atomic_xchg); + +int atomic_cmpxchg(atomic_t *v, int old, int new) +{ + int ret; + unsigned long flags; + + spin_lock_irqsave(ATOMIC_HASH(v), flags); + ret = v->counter; + if (likely(ret == old)) + v->counter = new; + + spin_unlock_irqrestore(ATOMIC_HASH(v), flags); + return ret; +} +EXPORT_SYMBOL(atomic_cmpxchg); + +int __atomic_add_unless(atomic_t *v, int a, int u) +{ + int ret; + unsigned long flags; + + spin_lock_irqsave(ATOMIC_HASH(v), flags); + ret = v->counter; + if (ret != u) + v->counter += a; + spin_unlock_irqrestore(ATOMIC_HASH(v), flags); + return ret; +} +EXPORT_SYMBOL(__atomic_add_unless); + +/* Atomic operations are already serializing */ +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_set); + +unsigned long ___set_bit(unsigned long *addr, unsigned long mask) +{ + unsigned long old, flags; + + spin_lock_irqsave(ATOMIC_HASH(addr), flags); + old = *addr; + *addr = old | mask; + spin_unlock_irqrestore(ATOMIC_HASH(addr), flags); + + return old & mask; +} +EXPORT_SYMBOL(___set_bit); + +unsigned long ___clear_bit(unsigned long *addr, unsigned long mask) +{ + unsigned long old, flags; + + spin_lock_irqsave(ATOMIC_HASH(addr), flags); + old = *addr; + *addr = old & ~mask; + spin_unlock_irqrestore(ATOMIC_HASH(addr), flags); + + return old & mask; +} +EXPORT_SYMBOL(___clear_bit); + +unsigned long ___change_bit(unsigned long *addr, unsigned long mask) +{ + unsigned long old, flags; + + spin_lock_irqsave(ATOMIC_HASH(addr), flags); + old = *addr; + *addr = old ^ mask; + spin_unlock_irqrestore(ATOMIC_HASH(addr), flags); + + return old & mask; +} +EXPORT_SYMBOL(___change_bit); + +unsigned long __cmpxchg_u32(volatile u32 *ptr, u32 old, u32 new) +{ + unsigned long flags; + u32 prev; + + spin_lock_irqsave(ATOMIC_HASH(ptr), flags); + if ((prev = *ptr) == old) + *ptr = new; + spin_unlock_irqrestore(ATOMIC_HASH(ptr), flags); + + return (unsigned long)prev; +} +EXPORT_SYMBOL(__cmpxchg_u32); + +unsigned long __xchg_u32(volatile u32 *ptr, u32 new) +{ + unsigned long flags; + u32 prev; + + spin_lock_irqsave(ATOMIC_HASH(ptr), flags); + prev = *ptr; + *ptr = new; + spin_unlock_irqrestore(ATOMIC_HASH(ptr), flags); + + return (unsigned long)prev; +} +EXPORT_SYMBOL(__xchg_u32); |