From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.17.9]) by ozlabs.org (Postfix) with ESMTP id BFA09B7063 for ; Sat, 12 Dec 2009 02:49:31 +1100 (EST) From: Arnd Bergmann To: linuxppc-dev@lists.ozlabs.org Subject: Re: AltiVec in the kernel Date: Fri, 11 Dec 2009 16:49:25 +0100 References: <20091211114543.GF24650@honey.hogyros.de> In-Reply-To: <20091211114543.GF24650@honey.hogyros.de> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Message-Id: <200912111649.25617.arnd@arndb.de> Cc: Simon Richter , Sebastian Siewior List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Friday 11 December 2009, Simon Richter wrote: > Hi, > > since there has been a thread on allowing the use of a coprocessor in > the kernel already: I am wondering if it'd make sense to use AltiVec for > AES in dm-crypt, and how difficult it would be to implement that. > > I'm using a PegasosII which has a G4 running at 1 GHz; I get around 3 > MB/s throughput when accessing harddisks. I think that could be > improved. > > If I understand correctly, the actual encryption work runs in a kernel > thread, which is scheduled normally, so it ought to be possible to > enable AltiVec for that thread; am I missing something here? Sebastian Siewior has implemented this some time ago: http://old.nabble.com/-RFC-0-3--Experiments-with-AES-AltiVec,-part-2-tc10034255.html You can try the old patches on your machine to see if they are any good there. Arnd <><