arch/arm64/include/asm/sync_bitops.h

   1 #ifndef __ASM_SYNC_BITOPS_H__
   2 #define __ASM_SYNC_BITOPS_H__
   3
   4 #include <asm/bitops.h>
   5 #include <asm/cmpxchg.h>
   6
   7 /* sync_bitops functions are equivalent to the SMP implementation of the
   8  * original functions, independently from CONFIG_SMP being defined.
   9  *
  10  * We need them because _set_bit etc are not SMP safe if !CONFIG_SMP. But
  11  * under Xen you might be communicating with a completely external entity
  12  * who might be on another CPU (e.g. two uniprocessor guests communicating
  13  * via event channels and grant tables). So we need a variant of the bit
  14  * ops which are SMP safe even on a UP kernel.
  15  */
  16
  17 #define sync_set_bit(nr, p)            set_bit(nr, p)
  18 #define sync_clear_bit(nr, p)          clear_bit(nr, p)
  19 #define sync_change_bit(nr, p)         change_bit(nr, p)
  20 #define sync_test_and_set_bit(nr, p)   test_and_set_bit(nr, p)
  21 #define sync_test_and_clear_bit(nr, p) test_and_clear_bit(nr, p)
  22 #define sync_test_and_change_bit(nr, p)        test_and_change_bit(nr, p)
  23 #define sync_test_bit(nr, addr)                test_bit(nr, addr)
  24 #define sync_cmpxchg                   cmpxchg
  25
  26 #endif