Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762154AbZCTXle (ORCPT ); Fri, 20 Mar 2009 19:41:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763095AbZCTXZo (ORCPT ); Fri, 20 Mar 2009 19:25:44 -0400 Received: from mga11.intel.com ([192.55.52.93]:55970 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763060AbZCTXZn (ORCPT ); Fri, 20 Mar 2009 19:25:43 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.38,397,1233561600"; d="scan'208";a="674719637" Message-ID: <49C425F5.8060309@intel.com> Date: Fri, 20 Mar 2009 16:25:41 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.19 (X11/20090105) MIME-Version: 1.0 To: Ilya Yanok CC: "H. Peter Anvin" , "Williams, Dan J" , "linux-raid@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "neilb@suse.de" , "Sosnowski, Maciej" , Yuri Tikhonov Subject: Re: [PATCH 06/13] async_tx: add support for asynchronous GF multiplication References: <20090318191248.20375.40560.stgit@dwillia2-linux.ch.intel.com> <20090318192046.20375.89854.stgit@dwillia2-linux.ch.intel.com> <49C26D91.10804@intel.com> <49C41C1E.4060401@zytor.com> <49C4201A.5060905@emcraft.com> In-Reply-To: <49C4201A.5060905@emcraft.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 941 Lines: 25 Ilya Yanok wrote: >>> >> That doesn't explain what you expect the code to do. It still doesn't >> make sense to me. > > We defined async_pq() function as hardware can do GF multiplication of > arbitrary elements and we want to take advantage of this fact. But by > the design of ASYNC_TX API we have to provide synchronous version of > that function too. > I don't think that makes sense since the algorithm doesn't use vector-vector multiplications and there is no need for them. As such, you're actively excluding support for hardware which only provides scalar-vector multiplication, even though that is all we need. In fact, vectorizing the constant doesn't make much sense. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/