On Fri, 20 Aug 2004, Andreas Dilger wrote:
> On Aug 20, 2004 13:59 -0400, Jean-Luc Cooke wrote:
> > Is there a reason why get_random_bytes() is unsuitable?
> >
> > Keeping the number of PRNGs in the kernel to a minimum should a goal we can
> > all share.
>
> For some uses a decent PRNG is enough, and the overhead of get_random_bytes()
> is much too high. We've needed something like this for a long time (something
> that gives decenly uniform numbers) and hacks to use useconds/cycles/etc do
> not cut it. I for one welcome a simple in-kernel interface to
> e.g. get_urandom_bytes() (or net_random() as this is maybe inappropriately
> called) that is only pseudo-random but fast and efficient.
>
> Cheers, Andreas
> --
> Andreas Dilger
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...
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',
Cheers,
Dick Johnson
Penguin : Linux version 2.4.26 on an i686 machine (5570.56 BogoMips).
Note 96.31% of all statistics are fiction.
rnd.S
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