def all_control_flow_elements_count(bpmn_graph):
    """
    Returns the total count of all control flow elements
    in the BPMNDiagramGraph instance.
    

    :param bpmn_graph: an instance of BpmnDiagramGraph representing BPMN model.
    :return: total count of the control flow elements in the BPMNDiagramGraph instance
    """

    gateway_counts = get_gateway_counts(bpmn_graph)
    events_counts = get_events_counts(bpmn_graph)
    control_flow_elements_counts = gateway_counts.copy()
    control_flow_elements_counts.update(events_counts)

    return sum([
                   count for name, count in control_flow_elements_counts.items()
                   ])