How to find the physical and logical kernel number in the kernel module?

Question

Are there kernel functions on Linux that return the number of the physical kernel and the logical kernel (in the case of Hyperthreading) on ​​which the kernel module is running?

Answer 1

Look at the end of include/linux/smp.h : smp_processor_id() gives you the number of the current executable CPU. get_cpu() will do the same, and also turn off prevention so that you stay that the processor until put_cpu() is called.

From user space, you can use sched_getcpu() or getcpu() to get the same information.