OpenCloudOS-Kernel/arch/x86/um/asm/barrier.h

29 lines
747 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_UM_BARRIER_H_
#define _ASM_UM_BARRIER_H_
#include <asm/alternative.h>
/*
* Force strict CPU ordering.
* And yes, this is required on UP too when we're talking
* to devices.
*/
#ifdef CONFIG_X86_32
#define mb() alternative("lock; addl $0,0(%%esp)", "mfence", X86_FEATURE_XMM2)
#define rmb() alternative("lock; addl $0,0(%%esp)", "lfence", X86_FEATURE_XMM2)
#define wmb() alternative("lock; addl $0,0(%%esp)", "sfence", X86_FEATURE_XMM)
#else /* CONFIG_X86_32 */
#define mb() asm volatile("mfence" : : : "memory")
#define rmb() asm volatile("lfence" : : : "memory")
#define wmb() asm volatile("sfence" : : : "memory")
#endif /* CONFIG_X86_32 */
#include <asm-generic/barrier.h>
#endif