cmpxchg-irq.h

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#ifndef __ASM_SH_CMPXCHG_IRQ_H
#define __ASM_SH_CMPXCHG_IRQ_H

#include <linux/irqflags.h>

static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
{
    unsigned long flags, retval;

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

static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
{
    unsigned long flags, retval;

    local_irq_save(flags);
    retval = *m;
    *m = val & 0xff;
    local_irq_restore(flags);
    return retval;
}

static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
    unsigned long new)
{
    __u32 retval;
    unsigned long flags;

    local_irq_save(flags);
    retval = *m;
    if (retval == old)
        *m = new;
    local_irq_restore(flags);       /* implies memory barrier  */
    return retval;
}

#endif /* __ASM_SH_CMPXCHG_IRQ_H */