void unregister_ftrace_graph(void)
{
	mutex_lock(&ftrace_lock);

	if (unlikely(!ftrace_graph_active))
		goto out;

	ftrace_graph_active--;
	ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
	ftrace_graph_entry = ftrace_graph_entry_stub;
	ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET);
	unregister_pm_notifier(&ftrace_suspend_notifier);
	unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);

 out:
	mutex_unlock(&ftrace_lock);
}

Unknown