162306a36Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */ 262306a36Sopenharmony_ci#ifndef __ASM_MCS_LOCK_H 362306a36Sopenharmony_ci#define __ASM_MCS_LOCK_H 462306a36Sopenharmony_ci 562306a36Sopenharmony_ci#ifdef CONFIG_SMP 662306a36Sopenharmony_ci#include <asm/spinlock.h> 762306a36Sopenharmony_ci 862306a36Sopenharmony_ci/* MCS spin-locking. */ 962306a36Sopenharmony_ci#define arch_mcs_spin_lock_contended(lock) \ 1062306a36Sopenharmony_cido { \ 1162306a36Sopenharmony_ci /* Ensure prior stores are observed before we enter wfe. */ \ 1262306a36Sopenharmony_ci smp_mb(); \ 1362306a36Sopenharmony_ci while (!(smp_load_acquire(lock))) \ 1462306a36Sopenharmony_ci wfe(); \ 1562306a36Sopenharmony_ci} while (0) \ 1662306a36Sopenharmony_ci 1762306a36Sopenharmony_ci#define arch_mcs_spin_unlock_contended(lock) \ 1862306a36Sopenharmony_cido { \ 1962306a36Sopenharmony_ci smp_store_release(lock, 1); \ 2062306a36Sopenharmony_ci dsb_sev(); \ 2162306a36Sopenharmony_ci} while (0) 2262306a36Sopenharmony_ci 2362306a36Sopenharmony_ci#endif /* CONFIG_SMP */ 2462306a36Sopenharmony_ci#endif /* __ASM_MCS_LOCK_H */ 25