// debugging dumps a CSV content for three levels of granularity
	// 1. row per priority-level
	c.UnlistedHandleFunc("/debug/api_priority_and_fairness/dump_priority_levels", cfgCtlr.dumpPriorityLevels)
	// 2. row per queue
	c.UnlistedHandleFunc("/debug/api_priority_and_fairness/dump_queues", cfgCtlr.dumpQueues)
	// 3. row per request
	c.UnlistedHandleFunc("/debug/api_priority_and_fairness/dump_requests", cfgCtlr.dumpRequests)
}

	defer m.lock.Unlock()
	m.trackCallers(path)

	m.pathToHandler[path] = handler
	m.refreshMuxLocked()
}

// UnlistedHandleFunc registers the handler function for the given pattern, but doesn't list it.
// If a handler already exists for pattern, Handle panics.
func (m *PathRecorderMux) UnlistedHandleFunc(path string, handler func(http.ResponseWriter, *http.Request)) {
	m.UnlistedHandle(path, http.HandlerFunc(handler))
}