[patch 10/14] s390: Use generic percpu

Christoph Lameter
2007-11-27T00:17:05Z

[-- Attachment #1: s390_generic_percpu --]
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s390 has a special way to determine the pointer to a per cpu area
plus there is a way to access the base of the per cpu area of the
currently executing processor.

Note: I had to do a minor change to ASM code. Please check that
this was done right.

Cc: schwidefsky@de.ibm.com
Signed-off-by: Christoph Lameter <clameter@sgi.com>

---
include/asm-s390/percpu.h | 33 +++++++++------------------------
1 file changed, 9 insertions(+), 24 deletions(-)

Index: linux-2.6/include/asm-s390/percpu.h
===================================================================
--- linux-2.6.orig/include/asm-s390/percpu.h 2007-11-24 16:20:38.776100537 -0800
+++ linux-2.6/include/asm-s390/percpu.h 2007-11-24 16:21:11.536101444 -0800
@@ -13,40 +13,25 @@
*/
#if defined(__s390x__) && defined(MODULE)

-#define __reloc_hide(var,offset) (*({ \
+#define SHIFT_PTR(ptr,offset) (({ \
extern int simple_identifier_##var(void); \
unsigned long *__ptr; \
- asm ( "larl %0,per_cpu__"#var"@GOTENT" \
- : "=a" (__ptr) : "X" (per_cpu__##var) ); \
- (typeof(&per_cpu__##var))((*__ptr) + (offset)); }))
+ asm ( "larl %0, %1@GOTENT" \
+ : "=a" (__ptr) : "X" (ptr) ); \
+ (typeof(ptr))((*__ptr) + (offset)); }))

#else

-#define __reloc_hide(var, offset) (*({ \
+#define SHIFT_PTR(ptr, offset) (({ \
extern int simple_identifier_##var(void); \
unsigned long __ptr; \
- asm ( "" : "=a" (__ptr) : "0" (&per_cpu__##var) ); \
- (typeof(&per_cpu__##var)) (__ptr + (offset)); }))
+ asm ( "" : "=a" (__ptr) : "0" (ptr) ); \
+ (typeof(ptr)) (__ptr + (offset)); }))

#endif

-#ifdef CONFIG_SMP
+#define __my_cpu_offset S390_lowcore.percpu_offset

-extern unsigned long __per_cpu_offset[NR_CPUS];
-
-#define __get_cpu_var(var) __reloc_hide(var,S390_lowcore.percpu_offset)
-#define __raw_get_cpu_var(var) __reloc_hide(var,S390_lowcore.percpu_offset)
-#define per_cpu(var,cpu) __reloc_hide(var,__per_cpu_offset[cpu])
-#define per_cpu_offset(x) (__per_cpu_offset[x])
-
-#else /* ! SMP */
-
-#define __get_cpu_var(var) __reloc_hide(var,0)
-#define __raw_get_cpu_var(var) __reloc_hide(var,0)
-#define per_cpu(var,cpu) __reloc_hide(var,0)
-
-#endif /* SMP */
-
-#define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
+#include <asm-generic/percpu.h>

#endif /* __ARCH_S390_PERCPU__ */

--