eventfd源代码分析

https://www.cnblogs.com/ck1020/p/7214310.html

eventfd使用方法

http://man7.org/linux/man-pages/man2/eventfd.2.html

KVM irqfd and ioeventfd

http://blog.allenx.org/2015/07/05/kvm-irqfd-and-ioeventfd