From mboxrd@z Thu Jan  1 00:00:00 1970
From: Elad Lahav <elahav@uwaterloo.ca>
Date: Sat, 13 Sep 2008 01:27:20 +0000
Subject: Re: Processor IDs on the Niagara
Message-Id: <48CB16F8.6020600@uwaterloo.ca>
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To: sparclinux@vger.kernel.org

> But on Niagara-T2 there are two integer units available amongst
> the 8 per-core virtual cpus.
> 
> And _that_ is what these values are meant to represent.
> 
> For example, on Niagara-T2:
> 
> 	core_id		proc_id
> cpu0:	1		0
> cpu1:	1		0
> cpu2:	1		0
> cpu3:	1		0
> cpu4:	1		1
> cpu5:	1		1
> cpu6:	1		1
> cpu7:	1		1

But what happens on the T2+? How is a physical package represented? 
Clearly the scheduler needs to be aware of the fact that two hardware 
threads are on different physical processors. As far as I know, the 
scheduler supports 4 levels: threads, cores, physical processors and 
NUMA nodes. I don't see how the current scheme falls into these categories.

Elad