From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Berg <johannes@sipsolutions.net>
Subject: Re: Buggy rhashtable walking
Date: Fri, 05 Aug 2016 12:50:33 +0200
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Cc: "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
	linux-wireless@vger.kernel.org, Thomas Graf <tgraf@suug.ch>,
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To: Herbert Xu <herbert@gondor.apana.org.au>
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On Fri, 2016-08-05 at 18:48 +0800, Herbert Xu wrote:
> On Fri, Aug 05, 2016 at 08:16:53AM +0200, Johannes Berg wrote:
> > 
> > Hm. Would you rather allocate a separate head entry for the
> > hashtable,
> > or chain the entries?
> 
> My plan is to build support for this directly into rhashtable.
> So I'm adding a struct rhlist_head that would be used in place
> of rhash_head for these cases and it'll carry an extra pointer
> for the list of identical entries.
> 
> I will then add an additional layer of insert/lookup interfaces
> for rhlist_head.

Oh, ok.

> So bottom-line is that if you have no identical entries that you
> only incur an extra 8 bytes per-object.
> 
Right.

Thanks!

johannes