Add cmpxchg_local to s390

Use the standard __cmpxchg for every type that can be updated atomically.
Use the new generic cmpxchg_local (disables interrupt) for other types.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mathieu Desnoyers 2008-02-07 00:16:24 -08:00 committed by Linus Torvalds
parent 85fdbe1b4b
commit fe4130131e
1 changed files with 41 additions and 3 deletions

View File

@ -201,9 +201,9 @@ static inline unsigned long __xchg(unsigned long x, void * ptr, int size)
#define __HAVE_ARCH_CMPXCHG 1
#define cmpxchg(ptr,o,n)\
((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
(unsigned long)(n),sizeof(*(ptr))))
#define cmpxchg(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
extern void __cmpxchg_called_with_bad_pointer(void);
@ -355,6 +355,44 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
#include <linux/irqflags.h>
#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 1:
case 2:
case 4:
#ifdef __s390x__
case 8:
#endif
return __cmpxchg(ptr, old, new, size);
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((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#ifdef __s390x__
#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
/*
* Use to set psw mask except for the first byte which
* won't be changed by this function.