From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David S. Miller" <davem@redhat.com>
Subject: Re: [RFC] enhanced version of net_random()
Date: Fri, 20 Aug 2004 12:48:23 -0700
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On Fri, 20 Aug 2004 15:22:09 -0400 (EDT)
"Richard B. Johnson" <root@chaos.analogic.com> wrote:

> The attached code will certainly work on Intel machines. It is
> in the public domain, having been modified by myself to produce
> a very long sequence...

How long a period does it have?  The one we're adding to the
networking has one which is 2^88.

> I wouldn't suggest converting it to 'C' because the rotation
> takes many CPU instructions when one tries to do the test, shift,
> and OR in 'C',

You only need 2 'shifts' and an 'or' to do a rotate in C.
No tests are needed.