[PATCH 10/23] make atomic_read() and atomic_set() behavior consistent on ia64

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From: Chris Snook
Date: Monday, August 13, 2007 - 4:23 am

From: Chris Snook <csnook@redhat.com>

Use volatile consistently in atomic.h on ia64.
This will do weird things without Andreas Schwab's fix:
http://lkml.org/lkml/2007/8/10/410

Signed-off-by: Chris Snook <csnook@redhat.com>

--- linux-2.6.23-rc3-orig/include/asm-ia64/atomic.h	2007-07-08 19:32:17.000000000 -0400
+++ linux-2.6.23-rc3/include/asm-ia64/atomic.h	2007-08-13 05:38:27.000000000 -0400
@@ -19,19 +19,34 @@
 
 /*
  * On IA-64, counter must always be volatile to ensure that that the
- * memory accesses are ordered.
+ * memory accesses are ordered.  This must be enforced each time that
+ * counter is read or written.
  */
-typedef struct { volatile __s32 counter; } atomic_t;
-typedef struct { volatile __s64 counter; } atomic64_t;
+typedef struct { __s32 counter; } atomic_t;
+typedef struct { __s64 counter; } atomic64_t;
 
 #define ATOMIC_INIT(i)		((atomic_t) { (i) })
 #define ATOMIC64_INIT(i)	((atomic64_t) { (i) })
 
-#define atomic_read(v)		((v)->counter)
-#define atomic64_read(v)	((v)->counter)
+static inline __s32 atomic_read(atomic_t *v)
+{
+        return *(volatile __s32 *)&v->counter;
+}
+
+static inline void atomic_set(atomic_t *v, __s32 i)
+{
+        *(volatile __s32 *)&v->counter = i;
+}
 
-#define atomic_set(v,i)		(((v)->counter) = (i))
-#define atomic64_set(v,i)	(((v)->counter) = (i))
+static inline __s64 atomic64_read(atomic64_t *v)
+{
+        return *(volatile __s64 *)&v->counter;
+}
+
+static inline void atomic64_set(atomic64_t *v, __s64 i)
+{
+        *(volatile __s64 *)&v->counter = i;
+}
 
 static __inline__ int
 ia64_atomic_add (int i, atomic_t *v)
-
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Messages in current thread:
[PATCH 10/23] make atomic_read() and atomic_set() behavior ..., Chris Snook, (Mon Aug 13, 4:23 am)
RE: [PATCH 10/23] make atomic_read() and atomic_set() beha ..., Christoph Lameter, (Tue Aug 14, 3:11 pm)
Re: [PATCH 1/23] document preferred use of volatile with a ..., Christoph Lameter, (Tue Aug 14, 3:45 pm)
Re: [PATCH 1/23] document preferred use of volatile with a ..., Christoph Lameter, (Tue Aug 14, 3:56 pm)
Re: [PATCH 1/23] document preferred use of volatile with a ..., Segher Boessenkool, (Thu Aug 16, 2:36 pm)
Re: [PATCH 11/23] make atomic_read() and atomic_set() beha ..., Segher Boessenkool, (Wed Aug 22, 7:24 am)
Re: [PATCH 11/23] make atomic_read() and atomic_set() beha ..., Segher Boessenkool, (Thu Aug 23, 12:29 pm)