kernel/arch/score/include/asm/cmpxchg.h

   1 #ifndef _ASM_SCORE_CMPXCHG_H
   2 #define _ASM_SCORE_CMPXCHG_H
   3
   4 #include <linux/irqflags.h>
   5
   6 struct __xchg_dummy { unsigned long a[100]; };
   7 #define __xg(x) ((struct __xchg_dummy *)(x))
   8
   9 static inline
  10 unsigned long __xchg(volatile unsigned long *m, unsigned long val)
  11 {
  12         unsigned long retval;
  13         unsigned long flags;
  14
  15         local_irq_save(flags);
  16         retval = *m;
  17         *m = val;
  18         local_irq_restore(flags);
  19         return retval;
  20 }
  21
  22 #define xchg(ptr, v)                                            \
  23         ((__typeof__(*(ptr))) __xchg((unsigned long *)(ptr),    \
  24                                         (unsigned long)(v)))
  25
  26 static inline unsigned long __cmpxchg(volatile unsigned long *m,
  27                                 unsigned long old, unsigned long new)
  28 {
  29         unsigned long retval;
  30         unsigned long flags;
  31
  32         local_irq_save(flags);
  33         retval = *m;
  34         if (retval == old)
  35                 *m = new;
  36         local_irq_restore(flags);
  37         return retval;
  38 }
  39
  40 #define cmpxchg(ptr, o, n)                                      \
  41         ((__typeof__(*(ptr))) __cmpxchg((unsigned long *)(ptr), \
  42                                         (unsigned long)(o),     \
  43                                         (unsigned long)(n)))
  44
  45 #define __HAVE_ARCH_CMPXCHG     1
  46
  47 #include <asm-generic/cmpxchg-local.h>
  48
  49 #endif /* _ASM_SCORE_CMPXCHG_H */