curl -o /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
yum install cloud-utils-growpart.x86_64
growpart /dev/sda 1 //1为分区标号，示例如下：
└─vda1 253:1 0 40G 0 part /
则命令为 growpart /dev/vda 1
再执行
xfs_growfs -d /dev/sda1
参考：
https://stackoverflow.com/questions/38160794/how-to-resize-root-partition-online-on-xfs-filesystem
