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Date: Mon, 14 Jul 2008 21:24:40 -0500
From: Nathan Lynch <ntl@pobox.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH] kill useless SMT code in prom_hold_cpus
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Benjamin Herrenschmidt wrote:
> On Tue, 2008-07-08 at 17:36 -0500, Nathan Lynch wrote:
> > I think this code that counts SMT threads and compares against NR_CPUS
> > is an artifact of pre-powerpc-merge ppc64.  We care about starting
> > only primary threads in the OF client code.
> > 
> > Signed-off-by: Nathan Lynch <ntl@pobox.com>
> 
> That looks good. I'm not merging it right now because I want to dbl
> check that it's allright on all SMT machines. IE. We compare reg[0]
> against _prom->cpu now instead of interrupt_server[0] and I thus
> want to ensure it's the same everywhere.

Thanks.  Looks like prom_find_boot_cpu is setting _prom->cpu to reg
(or 0), so I think it should be fine... a system where reg differed
from interrupt_server[0] would have been broken before this patch
anyway, I think?