detecting hyperthreading

[Pokala, Ravi]

-----Original Message-----
From: "lokadamus at gmx.de" <lokadamus at gmx.de>
Date: 2015-03-10, Tuesday at 09:09
To: Ravi Pokala <rpokala at panasas.com>, Rui Paulo <rpaulo at me.com>
Cc: "freebsd-hackers at freebsd.org" <freebsd-hackers at freebsd.org>
Subject: Re: detecting hyperthreading

>Well, i don't know, how a new system is showing the following sequence:
>dmesg | grep FreeBSD/SMP | grep HTT
>Answer: FreeBSD/SMP: 1 package(s) x 1 core(s) x 2 HTT threads
>
>Value $? is zero, but i will not reboot my system to look how it will
>change, when HTT is disabled.
>
>I make a portupgrade and this will need some hour. ;)

:-) I could probably use the machdep.hyperthreading_allowed *tunable* in
loader.conf to get a system running w/ HT disabled and see what the kernel
reports there, but all the suitable systems are shared, so I need to
coordinate w/ others.

-Ravi