cmpxchg.h

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#ifndef _ASM_SCORE_CMPXCHG_H
#define _ASM_SCORE_CMPXCHG_H

#include <linux/irqflags.h>

struct __xchg_dummy { unsigned long a[100]; };
#define __xg(x) ((struct __xchg_dummy *)(x))

static inline
unsigned long __xchg(volatile unsigned long *m, unsigned long val)
{
    unsigned long retval;
    unsigned long flags;

    local_irq_save(flags);
    retval = *m;
    *m = val;
    local_irq_restore(flags);
    return retval;
}

#define xchg(ptr, v)                        \
    ((__typeof__(*(ptr))) __xchg((unsigned long *)(ptr),    \
                    (unsigned long)(v)))

static inline unsigned long __cmpxchg(volatile unsigned long *m,
                unsigned long old, unsigned long new)
{
    unsigned long retval;
    unsigned long flags;

    local_irq_save(flags);
    retval = *m;
    if (retval == old)
        *m = new;
    local_irq_restore(flags);
    return retval;
}

#define cmpxchg(ptr, o, n)                  \
    ((__typeof__(*(ptr))) __cmpxchg((unsigned long *)(ptr), \
                    (unsigned long)(o), \
                    (unsigned long)(n)))

#define __HAVE_ARCH_CMPXCHG 1

#include <asm-generic/cmpxchg-local.h>

#endif /* _ASM_SCORE_CMPXCHG_H */