I am kernel newbie, and am trying to study the start_kernel() function.
My question is why smp_setup_processor_id(), which is called at the very beginning of start_kernel() is a void function for x86 architecture.
According to my understanding, any cpu come with more than one core could be thought as SMP(Therefore lots of x86 cpu fall into this catagory).

Any help or suggestion about a better place to post this question is appreciated!