oh_lock_histogram< H > Node1 oh_lock_histogram< H > - m_hist + oh_lock_histogram() + operator->() + ~oh_lock_histogram() - operator new() Node2 oh_lock_histogram_mutex # ATLAS_THREAD_SAFE + oh_lock_histogram_mutex() + ~oh_lock_histogram _mutex() + oh_lock_histogram_mutex() + operator=() + set_histogram_mutex() + reset_histogram_mutex() Node2->Node1