John Baldwin jhb at freebsd.org
Mon Mar 5 17:44:55 UTC 2012

On Friday, March 02, 2012 2:20:00 am Maninya M wrote:
> I was unable to get this information about the cpuid variable in the
> scheduler source code.
> How does cpuid get its value from the hardware?

The cpuid is a software ID value assigned during boot.  It is not
directly related to any specific hardware IDs.

> How is the CPUSTATES value obtained/changed with  hardware in the source
> code?

Do you mean, does cp_time[] handle hardware changes (hotplug CPUs, etc.)?
Currently that isn't supported, the kernel assumes the set of CPUs is
static for a given boot's lifetime.

John Baldwin

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