When should I write a Linux kernel module?

Question

Some people want to move code from user space to kernel space in Linux for some reason. A lot of times the reason seems to be that the code should have particularly high priorit

Answer 1

If you're asking such a question, then you shouldn't go to the kernel layer. Basically just wondering means you don't need to. The time of the context switch is so negligible that it doesn't matter anyway these days.