bugfix: avoid deadlock when exit
bugfix: avoid deadlock when exit

daishaowei/dpark,oceanjack/dpark,mageia/dpark,quxiaolong1504/dpark,mageia/dpark,Mignet/dpark,fe11x/dpark,304471720/dpark,ee08b397/dpark,zzl0/dpark,junmoa/dpark,junmoa/dpark,douban/dpark,windreamer/dpark,veritynoob/dpark,smarthomekit/dpark,quxiaolong1504/dpark,yanheven/dpark,304471720/dpark,daishaowei/dpark,douban/dpark,yhj630520/dpark,smarthomekit/dpark,fe11x/dpark,oceanjack/dpark,douban/dpark,windreamer/dpark,dogeyes/dpark,veritynoob/dpark,Mignet/dpark,douban/dpark,304471720/dpark,veritynoob/dpark,smarthomekit/dpark,yanheven/dpark,douban/dpark,dogeyes/dpark,yhj630520/dpark,windreamer/dpark,windreamer/dpark,zzl0/dpark,yhj630520/dpark,dogeyes/dpark