CPUID and CPU STATE

[Maninya M]

Thank you.
How do we get hardware cpuid?
Can we change the number of CPUs available to the scheduler (in the
scheduler code) dynamically, say completely cutting off a specific cpu core
from being used at all?



On 5 March 2012 22:51, John Baldwin <jhb at freebsd.org> wrote:

> 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
>



-- 
Maninya