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SubjectRe: [RFC] enhanced version of net_random()
If speed is what you want, and you want a period > 2^N.

Then a single get_rand_bytes() to fill a seed of a simple LFSR might do.

Seed value will be N+1 bits long.

Rochard's PRNG does not have a period > 2^32, that's for sure.


On Fri, Aug 20, 2004 at 12:48:23PM -0700, David S. Miller wrote:
> On Fri, 20 Aug 2004 15:22:09 -0400 (EDT)
> "Richard B. Johnson" <> 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.
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