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From: Thomas Monjalon <thomas.monjalon@6wind.com>
To: Bruce Richardson <bruce.richardson@intel.com>
Date: Thu, 06 Nov 2014 11:36:09 +0100
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Cc: dev@dpdk.org, jigsaw <jigsaw@gmail.com>
Subject: Re: [dpdk-dev] [PATCH] Add user defined tag calculation callback to
	librte_distributor.
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2014-11-06 09:22, Bruce Richardson:
> On Wed, Nov 05, 2014 at 07:24:13PM +0200, jigsaw wrote:
> > http://dpdk.org/browse/dpdk/tree/lib/librte_distributor/rte_distributor.c#n285
> > 
> >         new_tag = (next_mb->hash.rss | 1);
> > 
> > Why the logical OR is needed?
> 
> That's needed to ensure that we never track a tag with an actual value of zero.
> We instead always force the low bit to be 1, so that we can use zero as an
> "empty" value.

Bruce, could you check how this code may be better commented please?
This discussion shows that the distributor library probably needs more
explanations in the code or doxygen.

Thanks
-- 
Thomas