驅動程式 - Linux Device Driver(LDD) - 如何知道目前process是否位於container裡面

參考資料：
https://elixir.bootlin.com/linux/latest/source/include/linux/sched.h#L1612
https://stackoverflow.com/questions/9305992/if-threads-share-the-same-pid-how-can-they-be-identified

判斷TGID(Thread Group ID)

if (task_tgid_vnr(current) != current->tgid) {
	// in container
}

TGID