From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Wed, 01 Apr 2015 01:01:31 +0000
Subject: Re: [PATCH v8 RFC 0/3] Generic IOMMU pooled allocator
Message-Id: <1427850091.20500.150.camel@kernel.crashing.org>
List-Id: <sparclinux.vger.kernel.org>
References: <cover.1427761300.git.sowmini.varadhan@oracle.com>
 <20150331180642.GA13314@oracle.com>
In-Reply-To: <20150331180642.GA13314@oracle.com>
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To: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Cc: aik@au1.ibm.com, anton@au1.ibm.com, paulus@samba.org, sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, davem@davemloft.net

On Tue, 2015-03-31 at 14:06 -0400, Sowmini Varadhan wrote:
> Having bravely said that..
> 
> the IB team informs me that they see a 10% degradation using 
> the spin_lock as opposed to the trylock.
> 
> one path going forward is to continue processing this patch-set 
> as is. I can investigate this further, and later revise the spin_lock
> to the trylock, after we are certain that it is good/necessary.

Have they tried using more pools instead ?

Cheers,
Ben.