1 #ifndef __ASM_SYNC_BITOPS_H__ 2 #define __ASM_SYNC_BITOPS_H__ 3 4 #include <asm/bitops.h> 5 6 /* sync_bitops functions are equivalent to the SMP implementation of the 7 * original functions, independently from CONFIG_SMP being defined. 8 * 9 * We need them because _set_bit etc are not SMP safe if !CONFIG_SMP. But 10 * under Xen you might be communicating with a completely external entity 11 * who might be on another CPU (e.g. two uniprocessor guests communicating 12 * via event channels and grant tables). So we need a variant of the bit 13 * ops which are SMP safe even on a UP kernel. 14 */ 15 16 #define sync_set_bit(nr, p) _set_bit(nr, p) 17 #define sync_clear_bit(nr, p) _clear_bit(nr, p) 18 #define sync_change_bit(nr, p) _change_bit(nr, p) 19 #define sync_test_and_set_bit(nr, p) _test_and_set_bit(nr, p) 20 #define sync_test_and_clear_bit(nr, p) _test_and_clear_bit(nr, p) 21 #define sync_test_and_change_bit(nr, p) _test_and_change_bit(nr, p) 22 #define sync_test_bit(nr, addr) test_bit(nr, addr) 23 #define sync_cmpxchg cmpxchg 24 25 26 #endif 27