getting the cpuid for a userspace process ?

[Poul-Henning Kamp]

In message <201110251342.45194.jhb at freebsd.org>, John Baldwin writes:
>On Tuesday, October 25, 2011 11:06:22 am Luigi Rizzo wrote:
>> as the subject says... is there any way to get the current
>> CPU id for a userspace process (of course,
>> valid only at the time the function is called as the
>> process might be arbitrarily moved while it runs)
>
>Not from userland, no.  On x86 you can use cpuid to fetch the APIC ID, but 
>that does not map 1:1 to FreeBSD cpu IDs.

How does JEmalloc do it ?


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Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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