templink

http://guojing.me/linux-kernel-architecture/posts/wait-queue/

http://guojing.me/linux-kernel-architecture/tags/#等待队列

http://www.science.unitn.it/~fiorella/guidelinux/tlk/node5.html

https://www.experts-exchange.com/questions/20754965/How-to-peek-a-socket-in-a-synchronouos-TCP-connection-without-blocking.html

   Wait:DelayExec

http://huenlil.pixnet.net/blog/post/25190567-%5B%E8%BD%89%5Dlinux-kernel---wait-queue.