| /* |
| * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO) |
| * (a.k.a. Fault Tolerance or Continuous Replication) |
| * |
| * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD. |
| * Copyright (c) 2016 FUJITSU LIMITED |
| * Copyright (c) 2016 Intel Corporation |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2 or |
| * later. See the COPYING file in the top-level directory. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "migration/colo.h" |
| #include "migration/failover.h" |
| #include "qemu/main-loop.h" |
| #include "migration.h" |
| #include "qapi/error.h" |
| #include "qapi/qapi-commands-migration.h" |
| #include "qapi/qmp/qerror.h" |
| #include "qemu/error-report.h" |
| #include "trace.h" |
| |
| static QEMUBH *failover_bh; |
| static FailoverStatus failover_state; |
| |
| static void colo_failover_bh(void *opaque) |
| { |
| int old_state; |
| |
| qemu_bh_delete(failover_bh); |
| failover_bh = NULL; |
| |
| old_state = failover_set_state(FAILOVER_STATUS_REQUIRE, |
| FAILOVER_STATUS_ACTIVE); |
| if (old_state != FAILOVER_STATUS_REQUIRE) { |
| error_report("Unknown error for failover, old_state = %s", |
| FailoverStatus_str(old_state)); |
| return; |
| } |
| |
| colo_do_failover(); |
| } |
| |
| void failover_request_active(Error **errp) |
| { |
| if (failover_set_state(FAILOVER_STATUS_NONE, |
| FAILOVER_STATUS_REQUIRE) != FAILOVER_STATUS_NONE) { |
| error_setg(errp, "COLO failover is already actived"); |
| return; |
| } |
| failover_bh = qemu_bh_new(colo_failover_bh, NULL); |
| qemu_bh_schedule(failover_bh); |
| } |
| |
| void failover_init_state(void) |
| { |
| failover_state = FAILOVER_STATUS_NONE; |
| } |
| |
| FailoverStatus failover_set_state(FailoverStatus old_state, |
| FailoverStatus new_state) |
| { |
| FailoverStatus old; |
| |
| old = atomic_cmpxchg(&failover_state, old_state, new_state); |
| if (old == old_state) { |
| trace_colo_failover_set_state(FailoverStatus_str(new_state)); |
| } |
| return old; |
| } |
| |
| FailoverStatus failover_get_state(void) |
| { |
| return atomic_read(&failover_state); |
| } |
| |
| void qmp_x_colo_lost_heartbeat(Error **errp) |
| { |
| if (get_colo_mode() == COLO_MODE_NONE) { |
| error_setg(errp, QERR_FEATURE_DISABLED, "colo"); |
| return; |
| } |
| |
| failover_request_active(errp); |
| } |