blob: 9f0dcdf28f465cb120c9aff027883d4673e5044b (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
|
/*
* Copyright (C) 2016, Emilio G. Cota <cota@braap.org>
*
* License: GNU GPL, version 2.
* See the COPYING file in the top-level directory.
*/
#ifndef QEMU_PROCESSOR_H
#define QEMU_PROCESSOR_H
#if defined(__i386__) || defined(__x86_64__)
# define cpu_relax() asm volatile("rep; nop" ::: "memory")
#elif defined(__aarch64__)
# define cpu_relax() asm volatile("yield" ::: "memory")
#elif defined(__powerpc64__)
/* set Hardware Multi-Threading (HMT) priority to low; then back to medium */
# define cpu_relax() asm volatile("or 1, 1, 1;" \
"or 2, 2, 2;" ::: "memory")
#else
# define cpu_relax() barrier()
#endif
#endif /* QEMU_PROCESSOR_H */
|