Add cmpxchg_local to parisc
Mathieu Desnoyers [Thu, 7 Feb 2008 08:16:21 +0000 (00:16 -0800)]
Use the new generic cmpxchg_local (disables interrupt). Also use the generic
cmpxchg as fallback if SMP is not set.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-parisc/atomic.h

index e894ee3..57fcc4a 100644 (file)
@@ -122,6 +122,39 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new_, int size)
                                    (unsigned long)_n_, sizeof(*(ptr))); \
   })
 
+#include <asm-generic/cmpxchg-local.h>
+
+static inline unsigned long __cmpxchg_local(volatile void *ptr,
+                                     unsigned long old,
+                                     unsigned long new_, int size)
+{
+       switch (size) {
+#ifdef CONFIG_64BIT
+       case 8: return __cmpxchg_u64((unsigned long *)ptr, old, new_);
+#endif
+       case 4: return __cmpxchg_u32(ptr, old, new_);
+       default:
+               return __cmpxchg_local_generic(ptr, old, new_, size);
+       }
+}
+
+/*
+ * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
+ * them available.
+ */
+#define cmpxchg_local(ptr, o, n)                                       \
+       ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
+                       (unsigned long)(n), sizeof(*(ptr))))
+#ifdef CONFIG_64BIT
+#define cmpxchg64_local(ptr, o, n)                                     \
+  ({                                                                   \
+       BUILD_BUG_ON(sizeof(*(ptr)) != 8);                              \
+       cmpxchg_local((ptr), (o), (n));                                 \
+  })
+#else
+#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
+#endif
+
 /* Note that we need not lock read accesses - aligned word writes/reads
  * are atomic, so a reader never sees unconsistent values.
  *