1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __ASM_SYNC_BITOPS_H__ 3 #define __ASM_SYNC_BITOPS_H__ 4 5 #include <asm/bitops.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 27 #endif 28