https://blog.wongcw.com/2019/09/09/%e4%bd%99%e6%89%bf%e6%9d%b1%e5%9b%9e%e6%87%89arm%e6%96%b7%e4%be%9b%e9%a2%a8%e9%9a%aa%ef%bc%9a%e6%88%91%e5%80%91%e6%ba%96%e5%82%99%e4%ba%86%e8%87%aa%e5%b7%b1%e7%9a%84cpu/