[patch 23/23] Add cmpxchg_local to xtensa

Mathieu Desnoyers
2007-08-12T15:41:12Z

[-- Attachment #1: add-cmpxchg-local-to-xtensa.patch --]
[-- Type: text/plain, Size: 1631 bytes --]

Use the architecture specific __cmpxchg_u32 for 32 bits cmpxchg)_local. Else,
use the new generic cmpxchg_local (disables interrupt).

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: clameter@sgi.com
chris@zankel.net
---
include/asm-xtensa/system.h | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

Index: linux-2.6-lttng/include/asm-xtensa/system.h
===================================================================
--- linux-2.6-lttng.orig/include/asm-xtensa/system.h 2007-07-23 11:29:18.000000000 -0400
+++ linux-2.6-lttng/include/asm-xtensa/system.h 2007-07-23 11:32:32.000000000 -0400
@@ -156,8 +156,30 @@ __cmpxchg(volatile void *ptr, unsigned l
(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) {
+ case 4:
+ return __cmpxchg_u32(ptr, old, new);
+ default:
+ return __cmpxchg_local_generic(ptr, old, new, size);
+ }

+ return old;
+}
+
+/*
+ * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
+ * them available.
+ */
+#define cmpxchg_local(ptr,o,n) \
+ (__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o), \
+ (unsigned long)(n), sizeof(*(ptr)))
+#define cmpxchg64_local(ptr,o,n) __cmpxchg64_local_generic((ptr), (o), (n))

/*
* xchg_u32