When we register a cn_proc listening event, the proc_event_num_listener variable will be incremented by one, but if PROC_CN_MCAST_IGNORE is not called, the count will not decrease. This will cause the proc_*_connector function to take the wrong path. It will reappear when the forkstat tool exits via ctrl + c. We solve this problem by determining whether there are still listeners to clear proc_event_num_listener. Signed-off-by: wangkeqi <wangkeqiwang@didiglobal.com> Signed-off-by: David S. Miller <davem@davemloft.net>