Re: [PATCH v2:3/3]Export cpu topology by sysfs

Russ Anderson
2006-01-09T17:41:03Z

Zhang, Yanmin wrote:
>
> >>In practice does the division of bits between core and thread in the
> >>apic id differ between cpus in the same system?
>
> 2) On ia64, ia64 manual says that cpu physical id/core id/thread id are got by pal call. It doesn't mention how to divide apic id to get physical id/core id/thread id.

The socket_id, core_id, and thread_id are part of cpuinfo_ia64.
They are set up in arch/ia64/kernel/smpboot.c: identify_siblings()

You cannot make assumptions about "the division of bits", but must rely on
the values returned by pal.

--
Russ Anderson, OS RAS/Partitioning Project Lead
SGI - Silicon Graphics Inc rja@sgi.com