30 lines
776 B
C
30 lines
776 B
C
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
#ifndef _ASM_UM_BARRIER_H_
|
||
|
#define _ASM_UM_BARRIER_H_
|
||
|
|
||
|
#include <asm/cpufeatures.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
|