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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: RW <rwmaillists@googlemail.com>
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Date: Wed, 03 Oct 2012 11:32:45 +0200
In-Reply-To: <20121003011607.5553fe48@gumby.homeunix.com> (RW's message of
	"Wed, 3 Oct 2012 01:16:07 +0100")
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Cc: Jonathan Anderson <jonathan.anderson@cl.cam.ac.uk>,
	Pawel Jakub Dawidek <pjd@freebsd.org>,
	John Baldwin <jhb@freebsd.org>, Ben Laurie <benl@freebsd.org>,
	freebsd-security@freebsd.org, Mariusz Gromada <mariusz.gromada@gmail.com>
Subject: Re: Collecting entropy from device_attach() times.
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RW <rwmaillists@googlemail.com> writes:
> It doesn't compute it in a weird way for amd64 and most i386 systems.
> Where possible, get_cyclecount is just a wrapper for rdtsc, which I
> think it will be for all the systems you quoted (with the possible
> exception of virtualbox).

No.  All the machines I tested it on had TSCs, but not all i386 machines
we support do, so get_cyclecount() is always a function call on i386.
Look at the code, or heck, disassemble my kernel if you don't believe
me.

(did you even look at my numbers?)

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no