kernel/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
   6 static 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
  17 static 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
  28 static 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 */