oh_scoped_lock_histogram Node1 oh_scoped_lock_histogram + oh_scoped_lock_histogram() + ~oh_scoped_lock_histogram() - operator new() Node2 oh_lock_histogram_mutex + oh_lock_histogram_mutex() + ~oh_lock_histogram _mutex() + oh_lock_histogram_mutex() + operator=() + set_histogram_mutex() + reset_histogram_mutex() Node2->Node1 Node3 std::mutex Node3->Node2 #ATLAS_THREAD_SAFE