Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

[linux-2.6-block.git] / arch / sparc / lib / atomic32.c

diff --git a/arch/sparc/lib/atomic32.c b/arch/sparc/lib/atomic32.c
index 5010df4973879fb1b17e689e01ae11ca754ffc56..465a901a0ada71aef7ac08e36c90b7f528ae809d 100644 (file)
--- a/arch/sparc/lib/atomic32.c
+++ b/arch/sparc/lib/atomic32.c
@@ -173,6 +173,20 @@ unsigned long __cmpxchg_u32(volatile u32 *ptr, u32 old, u32 new)
 }
 EXPORT_SYMBOL(__cmpxchg_u32);
 
+u64 __cmpxchg_u64(u64 *ptr, u64 old, u64 new)
+{
+       unsigned long flags;
+       u64 prev;
+
+       spin_lock_irqsave(ATOMIC_HASH(ptr), flags);
+       if ((prev = *ptr) == old)
+               *ptr = new;
+       spin_unlock_irqrestore(ATOMIC_HASH(ptr), flags);
+
+       return prev;
+}
+EXPORT_SYMBOL(__cmpxchg_u64);
+
 unsigned long __xchg_u32(volatile u32 *ptr, u32 new)
 {
        unsigned long flags;