62 строки
1.4 KiB
C
62 строки
1.4 KiB
C
/*
|
|
* Atomics xchg/cmpxchg for PKUnity SoC and UniCore ISA
|
|
*
|
|
* Copyright (C) 2001-2012 GUAN Xue-tao
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#ifndef __UNICORE_CMPXCHG_H__
|
|
#define __UNICORE_CMPXCHG_H__
|
|
|
|
/*
|
|
* Generate a link failure on undefined symbol if the pointer points to a value
|
|
* of unsupported size.
|
|
*/
|
|
extern void __xchg_bad_pointer(void);
|
|
|
|
static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
|
|
int size)
|
|
{
|
|
unsigned long ret;
|
|
|
|
switch (size) {
|
|
case 1:
|
|
asm volatile("swapb %0, %1, [%2]"
|
|
: "=&r" (ret)
|
|
: "r" (x), "r" (ptr)
|
|
: "memory", "cc");
|
|
break;
|
|
case 4:
|
|
asm volatile("swapw %0, %1, [%2]"
|
|
: "=&r" (ret)
|
|
: "r" (x), "r" (ptr)
|
|
: "memory", "cc");
|
|
break;
|
|
default:
|
|
__xchg_bad_pointer();
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
#define xchg(ptr, x) \
|
|
((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
|
|
|
|
#include <asm-generic/cmpxchg-local.h>
|
|
|
|
/*
|
|
* cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
|
|
* them available.
|
|
*/
|
|
#define cmpxchg_local(ptr, o, n) \
|
|
((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), \
|
|
(unsigned long)(o), (unsigned long)(n), sizeof(*(ptr))))
|
|
#define cmpxchg64_local(ptr, o, n) \
|
|
__cmpxchg64_local_generic((ptr), (o), (n))
|
|
|
|
#include <asm-generic/cmpxchg.h>
|
|
|
|
#endif /* __UNICORE_CMPXCHG_H__ */
|