migration: pause-before-switchover for postcopy

Add pause-before-switchover support for postcopy.
After starting postcopy it will transition
    active->pre-switchover->postcopy_active

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This commit is contained in:
Dr. David Alan Gilbert 2017-10-20 10:05:56 +01:00 committed by Juan Quintela
parent a7b36b486d
commit 0331c8cabf

View File

@ -104,6 +104,9 @@ enum mig_rp_message_type {
static MigrationState *current_migration;
static bool migration_object_check(MigrationState *ms, Error **errp);
static int migration_maybe_pause(MigrationState *s,
int *current_active_state,
int new_state);
void migration_object_init(void)
{
@ -1820,8 +1823,11 @@ static int postcopy_start(MigrationState *ms, bool *old_vm_running)
QEMUFile *fb;
int64_t time_at_stop = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
bool restart_block = false;
migrate_set_state(&ms->state, MIGRATION_STATUS_ACTIVE,
MIGRATION_STATUS_POSTCOPY_ACTIVE);
int cur_state = MIGRATION_STATUS_ACTIVE;
if (!migrate_pause_before_switchover()) {
migrate_set_state(&ms->state, MIGRATION_STATUS_ACTIVE,
MIGRATION_STATUS_POSTCOPY_ACTIVE);
}
trace_postcopy_start();
qemu_mutex_lock_iothread();
@ -1835,6 +1841,12 @@ static int postcopy_start(MigrationState *ms, bool *old_vm_running)
goto fail;
}
ret = migration_maybe_pause(ms, &cur_state,
MIGRATION_STATUS_POSTCOPY_ACTIVE);
if (ret < 0) {
goto fail;
}
ret = bdrv_inactivate_all();
if (ret < 0) {
goto fail;
@ -1977,7 +1989,9 @@ fail:
* migrate_pause_before_switchover called with the iothread locked
* Returns: 0 on success
*/
static int migration_maybe_pause(MigrationState *s, int *current_active_state)
static int migration_maybe_pause(MigrationState *s,
int *current_active_state,
int new_state)
{
if (!migrate_pause_before_switchover()) {
return 0;
@ -1998,11 +2012,11 @@ static int migration_maybe_pause(MigrationState *s, int *current_active_state)
MIGRATION_STATUS_PRE_SWITCHOVER);
qemu_sem_wait(&s->pause_sem);
migrate_set_state(&s->state, MIGRATION_STATUS_PRE_SWITCHOVER,
MIGRATION_STATUS_DEVICE);
*current_active_state = MIGRATION_STATUS_DEVICE;
new_state);
*current_active_state = new_state;
qemu_mutex_lock_iothread();
return s->state == MIGRATION_STATUS_DEVICE ? 0 : -EINVAL;
return s->state == new_state ? 0 : -EINVAL;
}
/**
@ -2031,7 +2045,8 @@ static void migration_completion(MigrationState *s, int current_active_state,
bool inactivate = !migrate_colo_enabled();
ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
if (ret >= 0) {
ret = migration_maybe_pause(s, &current_active_state);
ret = migration_maybe_pause(s, &current_active_state,
MIGRATION_STATUS_DEVICE);
}
if (ret >= 0) {
qemu_file_set_rate_limit(s->to_dst_file, INT64_MAX);