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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
Subject: Re: svn commit: r274739 - head/sys/mips/conf
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Date: Tue, 25 Nov 2014 09:46:31 +0100
In-Reply-To: <90678.1416897647@critter.freebsd.dk> (Poul-Henning Kamp's
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Cc: arch@freebsd.org, Mark R V Murray <mark@grondar.org>,
 Ian Lepore <ian@FreeBSD.org>
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"Poul-Henning Kamp" <phk@phk.freebsd.dk> writes:
> Warner Losh <imp@bsdimp.com> writes:
> > What's the minimum specs required for get_cyclecount()?
> In randomness context:  That there exists a complex and unpredictable
> cache-hierarchy which makes the exact number of cycles for any one
> instruction pseudo-random.

No.  It just needs to be monotonic across cores and have reasonably high
resolution.

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