vfio/migration: Move from STOP_COPY to STOP in vfio_save_cleanup()

Changing the device state from STOP_COPY to STOP can take time as the
device may need to free resources and do other operations as part of the
transition. Currently, this is done in vfio_save_complete_precopy() and
therefore it is counted in the migration downtime.

To avoid this, change the device state from STOP_COPY to STOP in
vfio_save_cleanup(), which is called after migration has completed and
thus is not part of migration downtime.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
This commit is contained in:
Avihai Horon 2023-08-02 11:14:44 +03:00 committed by Cédric Le Goater
parent c5ea91da44
commit 5485298ce0

View File

@ -383,6 +383,19 @@ static void vfio_save_cleanup(void *opaque)
VFIODevice *vbasedev = opaque;
VFIOMigration *migration = vbasedev->migration;
/*
* Changing device state from STOP_COPY to STOP can take time. Do it here,
* after migration has completed, so it won't increase downtime.
*/
if (migration->device_state == VFIO_DEVICE_STATE_STOP_COPY) {
/*
* If setting the device in STOP state fails, the device should be
* reset. To do so, use ERROR state as a recover state.
*/
vfio_migration_set_state(vbasedev, VFIO_DEVICE_STATE_STOP,
VFIO_DEVICE_STATE_ERROR);
}
g_free(migration->data_buffer);
migration->data_buffer = NULL;
migration->precopy_init_size = 0;
@ -508,12 +521,6 @@ static int vfio_save_complete_precopy(QEMUFile *f, void *opaque)
return ret;
}
/*
* If setting the device in STOP state fails, the device should be reset.
* To do so, use ERROR state as a recover state.
*/
ret = vfio_migration_set_state(vbasedev, VFIO_DEVICE_STATE_STOP,
VFIO_DEVICE_STATE_ERROR);
trace_vfio_save_complete_precopy(vbasedev->name, ret);
return ret;