kernel/arch/metag/include/asm/cmpxchg_lock1.h

   1 #ifndef __ASM_METAG_CMPXCHG_LOCK1_H
   2 #define __ASM_METAG_CMPXCHG_LOCK1_H
   3
   4 #include <asm/global_lock.h>
   5
   6 /* Use LOCK2 as these have to be atomic w.r.t. ordinary accesses. */
   7
   8 static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
   9 {
  10         unsigned long flags, retval;
  11
  12         __global_lock2(flags);
  13         fence();
  14         retval = *m;
  15         *m = val;
  16         __global_unlock2(flags);
  17         return retval;
  18 }
  19
  20 static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
  21 {
  22         unsigned long flags, retval;
  23
  24         __global_lock2(flags);
  25         fence();
  26         retval = *m;
  27         *m = val & 0xff;
  28         __global_unlock2(flags);
  29         return retval;
  30 }
  31
  32 static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
  33                                           unsigned long new)
  34 {
  35         __u32 retval;
  36         unsigned long flags;
  37
  38         __global_lock2(flags);
  39         retval = *m;
  40         if (retval == old) {
  41                 fence();
  42                 *m = new;
  43         }
  44         __global_unlock2(flags);
  45         return retval;
  46 }
  47
  48 #endif /* __ASM_METAG_CMPXCHG_LOCK1_H */