115 lines
3.3 KiB
C
115 lines
3.3 KiB
C
/*
|
|
* forked from parisc asm/atomic.h which was:
|
|
* Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
|
|
* Copyright (C) 2006 Kyle McMartin <kyle@parisc-linux.org>
|
|
*/
|
|
|
|
#ifndef _ASM_PARISC_CMPXCHG_H_
|
|
#define _ASM_PARISC_CMPXCHG_H_
|
|
|
|
/* This should get optimized out since it's never called.
|
|
** Or get a link error if xchg is used "wrong".
|
|
*/
|
|
extern void __xchg_called_with_bad_pointer(void);
|
|
|
|
/* __xchg32/64 defined in arch/parisc/lib/bitops.c */
|
|
extern unsigned long __xchg8(char, char *);
|
|
extern unsigned long __xchg32(int, int *);
|
|
#ifdef CONFIG_64BIT
|
|
extern unsigned long __xchg64(unsigned long, unsigned long *);
|
|
#endif
|
|
|
|
/* optimizer better get rid of switch since size is a constant */
|
|
static inline unsigned long
|
|
__xchg(unsigned long x, __volatile__ void *ptr, int size)
|
|
{
|
|
switch (size) {
|
|
#ifdef CONFIG_64BIT
|
|
case 8: return __xchg64(x, (unsigned long *) ptr);
|
|
#endif
|
|
case 4: return __xchg32((int) x, (int *) ptr);
|
|
case 1: return __xchg8((char) x, (char *) ptr);
|
|
}
|
|
__xchg_called_with_bad_pointer();
|
|
return x;
|
|
}
|
|
|
|
/*
|
|
** REVISIT - Abandoned use of LDCW in xchg() for now:
|
|
** o need to test sizeof(*ptr) to avoid clearing adjacent bytes
|
|
** o and while we are at it, could CONFIG_64BIT code use LDCD too?
|
|
**
|
|
** if (__builtin_constant_p(x) && (x == NULL))
|
|
** if (((unsigned long)p & 0xf) == 0)
|
|
** return __ldcw(p);
|
|
*/
|
|
#define xchg(ptr, x) \
|
|
((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
|
|
|
|
/* bug catcher for when unsupported size is used - won't link */
|
|
extern void __cmpxchg_called_with_bad_pointer(void);
|
|
|
|
/* __cmpxchg_u32/u64 defined in arch/parisc/lib/bitops.c */
|
|
extern unsigned long __cmpxchg_u32(volatile unsigned int *m, unsigned int old,
|
|
unsigned int new_);
|
|
extern u64 __cmpxchg_u64(volatile u64 *ptr, u64 old, u64 new_);
|
|
|
|
/* don't worry...optimizer will get rid of most of this */
|
|
static inline unsigned long
|
|
__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new_, int size)
|
|
{
|
|
switch (size) {
|
|
#ifdef CONFIG_64BIT
|
|
case 8: return __cmpxchg_u64((u64 *)ptr, old, new_);
|
|
#endif
|
|
case 4: return __cmpxchg_u32((unsigned int *)ptr,
|
|
(unsigned int)old, (unsigned int)new_);
|
|
}
|
|
__cmpxchg_called_with_bad_pointer();
|
|
return old;
|
|
}
|
|
|
|
#define cmpxchg(ptr, o, n) \
|
|
({ \
|
|
__typeof__(*(ptr)) _o_ = (o); \
|
|
__typeof__(*(ptr)) _n_ = (n); \
|
|
(__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
|
|
(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((u64 *)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) \
|
|
({ \
|
|
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
|
|
|
|
#define cmpxchg64(ptr, o, n) __cmpxchg_u64(ptr, o, n)
|
|
|
|
#endif /* _ASM_PARISC_CMPXCHG_H_ */
|