Firstly, it was passed around. Let's just move it into MigrationState
just like many other variables as state of migration, renaming it to
vm_was_running.
One thing to mention is that for postcopy, we actually don't need this
knowledge at all since postcopy can't resume a VM even if it fails (we
can see that from the old code too: when we try to resume we also check
against "entered_postcopy" variable). So further we do this:
- in postcopy_start(), we don't update vm_old_running since useless
- in migration_thread(), we don't need to check entered_postcopy when
resume, since it's only used for precopy.
Comment this out too for that variable definition.
Reviewed-by: Juan Quintela <quint...@redhat.com>
Signed-off-by: Peter Xu <pet...@redhat.com>
---
migration/migration.c | 17 +++++++----------
migration/migration.h | 6 ++++++
2 files changed, 13 insertions(+), 10 deletions(-)
diff --git a/migration/migration.c b/migration/migration.c
index 343368c089..ca0c600178 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1272,6 +1272,7 @@ MigrationState *migrate_init(void)
s->start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
s->total_time = 0;
+ s->vm_was_running = false;
return s;
}
@@ -1846,7 +1847,7 @@ static int
await_return_path_close_on_source(MigrationState *ms)
* Switch from normal iteration to postcopy
* Returns non-0 on error
*/
-static int postcopy_start(MigrationState *ms, bool *old_vm_running)
+static int postcopy_start(MigrationState *ms)
{
int ret;
QIOChannelBuffer *bioc;
@@ -1864,7 +1865,6 @@ static int postcopy_start(MigrationState *ms, bool
*old_vm_running)
trace_postcopy_start_set_run();
qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
- *old_vm_running = runstate_is_running();
global_state_store();
ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
if (ret < 0) {
@@ -2055,11 +2055,9 @@ static int migration_maybe_pause(MigrationState *s,
*
* @s: Current migration state
* @current_active_state: The migration state we expect to be in
- * @*old_vm_running: Pointer to old_vm_running flag
* @*start_time: Pointer to time to update
*/
static void migration_completion(MigrationState *s, int current_active_state,
- bool *old_vm_running,
int64_t *start_time)
{
int ret;
@@ -2068,7 +2066,7 @@ static void migration_completion(MigrationState *s, int
current_active_state,
qemu_mutex_lock_iothread();
*start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
- *old_vm_running = runstate_is_running();
+ s->vm_was_running = runstate_is_running();
ret = global_state_store();
if (!ret) {
@@ -2174,7 +2172,6 @@ static void *migration_thread(void *opaque)
int64_t threshold_size = 0;
int64_t start_time = initial_time;
int64_t end_time;
- bool old_vm_running = false;
bool entered_postcopy = false;
/* The active state we expect to be in; ACTIVE or POSTCOPY_ACTIVE */
enum MigrationStatus current_active_state = MIGRATION_STATUS_ACTIVE;
@@ -2233,7 +2230,7 @@ static void *migration_thread(void *opaque)
pend_nonpost <= threshold_size &&
atomic_read(&s->start_postcopy)) {
- if (!postcopy_start(s, &old_vm_running)) {
+ if (!postcopy_start(s)) {
current_active_state =
MIGRATION_STATUS_POSTCOPY_ACTIVE;
entered_postcopy = true;
}
@@ -2245,7 +2242,7 @@ static void *migration_thread(void *opaque)
} else {
trace_migration_thread_low_pending(pending_size);
migration_completion(s, current_active_state,
- &old_vm_running, &start_time);
+ &start_time);
break;
}
}
@@ -2318,9 +2315,9 @@ static void *migration_thread(void *opaque)
* Fixme: we will run VM in COLO no matter its old running state.
* After exited COLO, we will keep running.
*/
- old_vm_running = true;
+ s->vm_was_running = true;
}
- if (old_vm_running && !entered_postcopy) {
+ if (s->vm_was_running) {
vm_start();
} else {
if (runstate_check(RUN_STATE_FINISH_MIGRATE)) {
diff --git a/migration/migration.h b/migration/migration.h
index 233ad68705..45053ae8c5 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -111,6 +111,12 @@ struct MigrationState
int64_t expected_downtime;
bool enabled_capabilities[MIGRATION_CAPABILITY__MAX];
int64_t setup_time;
+ /*
+ * Whether guest was running when we enter the completion stage.
+ * If migration is interrupted by any reason, we need to continue
+ * running the guest on source.
+ */
+ bool vm_was_running;
/* Flag set once the migration has been asked to enter postcopy */
bool start_postcopy;
--
2.14.3
