projects / mirror_qemu.git / blame
| Commit | Line | Data |
|---|---|---|
| a40161cb PB |
1 | /* |
| 2 | * Process-global memory barriers | |
| 3 | * | |
| 4 | * Copyright (c) 2018 Red Hat, Inc. | |
| 5 | * | |
| 6 | * Author: Paolo Bonzini <pbonzini@redhat.com> | |
| 7 | */ | |
| 8 | ||
| d6974846 BR |
9 | #include "qemu/osdep.h" |
| 10 | #include "qemu/sys_membarrier.h" | |
| 11 | #include "qemu/error-report.h" | |
| a40161cb PB |
12 | |
| 13 | #ifdef CONFIG_LINUX | |
| 14 | #include <linux/membarrier.h> | |
| 15 | #include <sys/syscall.h> | |
| 16 | ||
| 17 | static int | |
| 18 | membarrier(int cmd, int flags) | |
| 19 | { | |
| 20 | return syscall(__NR_membarrier, cmd, flags); | |
| 21 | } | |
| 22 | #endif | |
| 23 | ||
| 24 | void smp_mb_global(void) | |
| 25 | { | |
| 26 | #if defined CONFIG_WIN32 | |
| 27 | FlushProcessWriteBuffers(); | |
| 28 | #elif defined CONFIG_LINUX | |
| 29 | membarrier(MEMBARRIER_CMD_SHARED, 0); | |
| 30 | #else | |
| 31 | #error --enable-membarrier is not supported on this operating system. | |
| 32 | #endif | |
| 33 | } | |
| 34 | ||
| 35 | void smp_mb_global_init(void) | |
| 36 | { | |
| 37 | #ifdef CONFIG_LINUX | |
| 38 | int ret = membarrier(MEMBARRIER_CMD_QUERY, 0); | |
| 39 | if (ret < 0) { | |
| 40 | error_report("This QEMU binary requires the membarrier system call."); | |
| 41 | error_report("Please upgrade your system to a newer version of Linux"); | |
| 42 | exit(1); | |
| 43 | } | |
| 44 | if (!(ret & MEMBARRIER_CMD_SHARED)) { | |
| 45 | error_report("This QEMU binary requires MEMBARRIER_CMD_SHARED support."); | |
| 46 | error_report("Please upgrade your system to a newer version of Linux"); | |
| 47 | exit(1); | |
| 48 | } | |
| 49 | #endif | |
| 50 | } |