sync_bitops.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_SYNC_BITOPS_H__
#define __ASM_SYNC_BITOPS_H__
#include <asm/bitops.h>
#include <asm/cmpxchg.h>
/* sync_bitops functions are equivalent to the SMP implementation of the
* original functions, independently from CONFIG_SMP being defined.
*
* We need them because _set_bit etc are not SMP safe if !CONFIG_SMP. But
* under Xen you might be communicating with a completely external entity
* who might be on another CPU (e.g. two uniprocessor guests communicating
* via event channels and grant tables). So we need a variant of the bit
* ops which are SMP safe even on a UP kernel.
*/
#define sync_set_bit(nr, p) set_bit(nr, p)
#define sync_clear_bit(nr, p) clear_bit(nr, p)
#define sync_change_bit(nr, p) change_bit(nr, p)
#define sync_test_and_set_bit(nr, p) test_and_set_bit(nr, p)
#define sync_test_and_clear_bit(nr, p) test_and_clear_bit(nr, p)
#define sync_test_and_change_bit(nr, p) test_and_change_bit(nr, p)
#define sync_test_bit(nr, addr) test_bit(nr, addr)
#define arch_sync_cmpxchg arch_cmpxchg
#endif