LXR linux/arch/sh/include/asm/cmpxchg-irq.h

   1#ifndef __ASM_SH_CMPXCHG_IRQ_H
   2#define __ASM_SH_CMPXCHG_IRQ_H
   3
   4#include <linux/irqflags.h>
   5
   6static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
   7{
   8        unsigned long flags, retval;
   9
  10        local_irq_save(flags);
  11        retval = *m;
  12        *m = val;
  13        local_irq_restore(flags);
  14        return retval;
  15}
  16
  17static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
  18{
  19        unsigned long flags, retval;
  20
  21        local_irq_save(flags);
  22        retval = *m;
  23        *m = val & 0xff;
  24        local_irq_restore(flags);
  25        return retval;
  26}
  27
  28static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
  29        unsigned long new)
  30{
  31        __u32 retval;
  32        unsigned long flags;
  33
  34        local_irq_save(flags);
  35        retval = *m;
  36        if (retval == old)
  37                *m = new;
  38        local_irq_restore(flags);       /* implies memory barrier  */
  39        return retval;
  40}
  41
  42#endif /* __ASM_SH_CMPXCHG_IRQ_H */
  43