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Date: Sat, 7 Mar 2015 00:58:35 +0300
From: Slawa Olhovchenkov <slw@zxy.spb.ru>
To: Adrian Chadd <adrian@freebsd.org>
Subject: Re: RFC: Simplfying hyperthreading distinctions
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Cc: Andriy Gapon <avg@freebsd.org>,
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On Fri, Mar 06, 2015 at 01:37:04PM -0800, Adrian Chadd wrote:

> Hi!
> 
> 1) I'd rather we leave them as SMT/HTT as they're slightly different
> things. Who knows if intel will re-introduce this stuff in their more
> embedded CPU line at a future time, or add another threading type in
> the future. Being told about the distinction is nice.

May be diagnostic HTT[SMT] or HTT[HTT] is best chois?

> 2) I'd rather we had it more clearly defind - machdep.htt_allowed /
> machdep.smt_allowed . Again, I'd rather have the distinction in case
> Intel decide again to make their embedded things use old-style
> threading. (The intel edison/galilleo boards use P1 style cores that
> are low power, I can imagine a world where they reuse HTT for that.)

I think this distinction don't need -- any way this setup is per-box.
If you need to disable HTT/SMT -- you don't need to choise between
machdep.htt_allowed and machdep.smt_allowed -- only one exist.