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Date: Sat, 25 Apr 2015 04:49:35 -0700
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Christoph Lameter <cl@linux.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Jerome Glisse <j.glisse@gmail.com>, linux-kernel@vger.kernel.org,
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Subject: Re: Interacting with coherent memory on external devices
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On Fri, Apr 24, 2015 at 10:49:28AM -0500, Christoph Lameter wrote:
> On Fri, 24 Apr 2015, Paul E. McKenney wrote:
> 
> > can deliver, but where the cost of full-fledge hand tuning cannot be
> > justified.
> >
> > You seem to believe that this latter category is the empty set, which
> > I must confess does greatly surprise me.
> 
> If there are already compromises are being made then why would you want to
> modify the kernel for this? Some user space coding and device drivers
> should be sufficient.

The goal is to gain substantial performance improvement without any
user-space changes.

							Thanx, Paul