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From: Sven Eckelmann <sven@narfation.org>
Date: Mon, 26 Nov 2012 10:40:07 +0100
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Subject: Re: [B.A.T.M.A.N.] [PATCH 1/5] batman-adv: Use common Jenkins Hash
	implementation
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On Monday 26 November 2012 10:33:09 Antonio Quartulli wrote:
> On Sun, Nov 25, 2012 at 07:23:27PM +0100, Sven Eckelmann wrote:
> > An unoptimized version of the Jenkins one-at-a-time hash function is
> > copied all over the code wherever an hashtable is used. Instead the
> > optimized version shared between the whole kernel should be used to
> > reduce code duplication and keep bugs at a single point.
> > 
> > Only the TT and DAT code must use the old implementation to guarantee the
> > same distribution of the elements in the hash. The TT code needs it
> > because the CRC exchanged between the mesh nodes is computed over the
> > entries in the hash.
> Hi Sven,
> 
> I don't fully get why we can't use this new implementation in TT. What's
> wrong with the CRC computation?

The in kernel implementation will create a different hash sum -> tt entries 
will end up in a different bucket -> CRC will be different (please correct me 
about the last step... just had this problem in the back of my head).

Kind regards,
	Sven
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