1 | /* |
2 | * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO) |
3 | * (a.k.a. Fault Tolerance or Continuous Replication) |
4 | * |
5 | * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD. |
6 | * Copyright (c) 2016 FUJITSU LIMITED |
7 | * Copyright (c) 2016 Intel Corporation |
8 | * |
9 | * This work is licensed under the terms of the GNU GPL, version 2 or |
10 | * later. See the COPYING file in the top-level directory. |
11 | */ |
12 | |
13 | #include "qemu/osdep.h" |
14 | #include "migration/colo.h" |
15 | #include "migration/failover.h" |
16 | #include "qemu/main-loop.h" |
17 | #include "migration.h" |
18 | #include "qapi/error.h" |
19 | #include "qapi/qapi-commands-migration.h" |
20 | #include "qapi/qmp/qerror.h" |
21 | #include "qemu/error-report.h" |
22 | #include "trace.h" |
23 | |
24 | static QEMUBH *failover_bh; |
25 | static FailoverStatus failover_state; |
26 | |
27 | static void colo_failover_bh(void *opaque) |
28 | { |
29 | int old_state; |
30 | |
31 | qemu_bh_delete(failover_bh); |
32 | failover_bh = NULL; |
33 | |
34 | old_state = failover_set_state(FAILOVER_STATUS_REQUIRE, |
35 | FAILOVER_STATUS_ACTIVE); |
36 | if (old_state != FAILOVER_STATUS_REQUIRE) { |
37 | error_report("Unknown error for failover, old_state = %s" , |
38 | FailoverStatus_str(old_state)); |
39 | return; |
40 | } |
41 | |
42 | colo_do_failover(); |
43 | } |
44 | |
45 | void failover_request_active(Error **errp) |
46 | { |
47 | if (failover_set_state(FAILOVER_STATUS_NONE, |
48 | FAILOVER_STATUS_REQUIRE) != FAILOVER_STATUS_NONE) { |
49 | error_setg(errp, "COLO failover is already actived" ); |
50 | return; |
51 | } |
52 | failover_bh = qemu_bh_new(colo_failover_bh, NULL); |
53 | qemu_bh_schedule(failover_bh); |
54 | } |
55 | |
56 | void failover_init_state(void) |
57 | { |
58 | failover_state = FAILOVER_STATUS_NONE; |
59 | } |
60 | |
61 | FailoverStatus failover_set_state(FailoverStatus old_state, |
62 | FailoverStatus new_state) |
63 | { |
64 | FailoverStatus old; |
65 | |
66 | old = atomic_cmpxchg(&failover_state, old_state, new_state); |
67 | if (old == old_state) { |
68 | trace_colo_failover_set_state(FailoverStatus_str(new_state)); |
69 | } |
70 | return old; |
71 | } |
72 | |
73 | FailoverStatus failover_get_state(void) |
74 | { |
75 | return atomic_read(&failover_state); |
76 | } |
77 | |
78 | void qmp_x_colo_lost_heartbeat(Error **errp) |
79 | { |
80 | if (get_colo_mode() == COLO_MODE_NONE) { |
81 | error_setg(errp, QERR_FEATURE_DISABLED, "colo" ); |
82 | return; |
83 | } |
84 | |
85 | failover_request_active(errp); |
86 | } |
87 | |