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-rw-r--r--arch/sparc/lib/atomic32.c21
1 files changed, 16 insertions, 5 deletions
diff --git a/arch/sparc/lib/atomic32.c b/arch/sparc/lib/atomic32.c
index 2e64e8c3e8e..be46f654518 100644
--- a/arch/sparc/lib/atomic32.c
+++ b/arch/sparc/lib/atomic32.c
@@ -37,17 +37,28 @@ int __atomic_add_return(int i, atomic_t *v)
spin_unlock_irqrestore(ATOMIC_HASH(v), flags);
return ret;
}
+EXPORT_SYMBOL(__atomic_add_return);
-void atomic_set(atomic_t *v, int i)
+int atomic_cmpxchg(atomic_t *v, int old, int new)
{
+ int ret;
unsigned long flags;
- spin_lock_irqsave(ATOMIC_HASH(v), flags);
- v->counter = i;
+ 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_add_return);
-EXPORT_SYMBOL(atomic_set);
+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);