From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sebastien Dugue <sebastien.dugue@bull.net>
Subject: Re: [PATCH 2/2][RT] powerpc - Make the irq reverse mapping radix
 tree lockless
Date: Fri, 25 Jul 2008 10:36:01 +0200
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Cc: Peter Zijlstra <peterz@infradead.org>,
	Nick Piggin <nickpiggin@yahoo.com.au>,
	Linux-rt <linux-rt-users@vger.kernel.org>,
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	Paul Mackerras <paulus@samba.org>,
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	Tim Chavez <tinytim@us.ibm.com>,
	Jean Pierre Dion <jean-pierre.dion@bull.net>,
	Gilles Carry <Gilles.Carry@ext.bull.net>
To: benh@kernel.crashing.org
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On Fri, 25 Jul 2008 18:27:20 +1000 Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:

> On Fri, 2008-07-25 at 09:49 +0200, Peter Zijlstra wrote:
> > 
> > 
> > The only advantage of the concurrent radix tree over this model is that
> > it can potentially do multiple modification operations at the same time.
> 
> Yup, we do not need that for the irq revmap... concurrent lookup is all we need.
> 

  Shouldn't we care about concurrent insertion and deletion in the tree? I agree
that concern might be a bit artificial but in theory that can happen.

  Sebastien.