[patch 15/23] Add cmpxchg_local to parisc

Mathieu Desnoyers
2007-08-20T20:52:45Z

[-- Attachment #1: add-cmpxchg-local-to-parisc.patch --]
[-- Type: text/plain, Size: 1917 bytes --]

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: clameter@sgi.com
CC: parisc-linux@parisc-linux.org
---
include/asm-parisc/atomic.h | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)

Index: linux-2.6-lttng/include/asm-parisc/atomic.h
===================================================================
--- linux-2.6-lttng.orig/include/asm-parisc/atomic.h 2007-07-20 19:44:40.000000000 -0400
+++ linux-2.6-lttng/include/asm-parisc/atomic.h 2007-07-20 19:44:47.000000000 -0400
@@ -122,6 +122,35 @@ __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) {
+#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) 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.
*