Re: SMP problem....maybe ??

[Jay Estabrook compaq com]

>>> Rich Payne said:
> 
> 
> I noticed that regardless of how many processors are present in the box
> (this is either UP2000 or DP264) /proc/cpuinfo reports "cpus detected 2",
> followed by "CPUs probed x" where x is the real number of CPUs, now it
> does this even on a machine with 1 cpu and a uni kernel!
> 
> Now this value comes from hwrpb->nr_processors, which seems to be related
> to the INIT_HWRPB struct in aboot (am I even close here ?)

Oh, yes, you *are* close... ;-}

> So I guess the question is does anybody know why this is reporting 2 on
> SMP Tsunami machines? regardless of what's really there?

Yes, there is/was a bug in the CPU detection code, which goes away with
2.2.14 (the patch has been in there since pre9 or so, IIRC).

The HWRPB may say there's 2 or 4 CPUs, for a given architecture, in the
"nr_processors" field, and one is required to look deeper, at the per-CPU
data, to determine how many are really there.

TSUNAMI machines will always say 2 CPUs, I believe; RAWHIDE may say 4.

--Jay++

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Jay A Estabrook                       Alpha Engineering - LINUX
Compaq Computer Corp. - MRO1-2/K20    (508) 467-2080
200 Forest Street, Marlboro MA 01752  Jay.Estabrook@compaq.com
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