def enter_eventloop(self):
        """enter eventloop"""
        self.log.info("entering eventloop")
        # restore default_int_handler
        signal(SIGINT, default_int_handler)
        while self.eventloop is not None:
            try:
                self.eventloop(self)
            except KeyboardInterrupt:
                # Ctrl-C shouldn't crash the kernel
                self.log.error("KeyboardInterrupt caught in kernel")
                continue
            else:
                # eventloop exited cleanly, this means we should stop (right?)
                self.eventloop = None
                break
        self.log.info("exiting eventloop")
        # if eventloop exits, IOLoop should stop
        ioloop.IOLoop.instance().stop()
enter eventloop