From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH 2/2] udp: RCU handling for Unicast packets.
Date: Thu, 30 Oct 2008 12:04:20 +0100
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Cc: paulmck@linux.vnet.ibm.com, Corey Minyard <minyard@acm.org>,
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To: Eric Dumazet <dada1@cosmosbay.com>
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On Wed, 2008-10-29 at 21:00 +0100, Eric Dumazet wrote:

> 
> Hum... Another way of handling all those cases and avoid memory barriers
> would be to have different "NULL" pointers.
> 
> Each hash chain should have a unique "NULL" pointer (in the case of UDP, it
> can be the 128 values : [ (void*)0 .. (void *)127 ]

Why not use the bucket pointer as terminating condition?

Because all you really need is a pointer that is specific per bucket,
and not a valid element, right?