From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boaz Harrosh Subject: Re: [PATCH v2] fix sign extension with 1.5TB usb-storage LBD=y Date: Wed, 22 Apr 2009 14:27:12 +0300 Message-ID: <49EEFF10.3050306@panasas.com> References: <1240347174.10627.20.camel@nimitz> <20090421211858.GA1926@parisc-linux.org> <1240351210.10627.30.camel@nimitz> <49EEC82B.5040603@panasas.com> <20090422110921.GE1926@parisc-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from gw-ca.panasas.com ([209.116.51.66]:30164 "EHLO laguna.int.panasas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751409AbZDVL1k (ORCPT ); Wed, 22 Apr 2009 07:27:40 -0400 In-Reply-To: <20090422110921.GE1926@parisc-linux.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Matthew Wilcox Cc: Dave Hansen , linux-kernel , mdharm-usb@one-eyed-alien.net, linux-usb , usb-storage@lists.one-eyed-alien.net, James Bottomley , linux-scsi , viro On 04/22/2009 02:09 PM, Matthew Wilcox wrote: > On Wed, Apr 22, 2009 at 10:32:59AM +0300, Boaz Harrosh wrote: >> These are actually aligned access it might be worth sacrificing a cast >> to be32/64 for sake of speed. > > "for sake of speed"? How often do you think we ask a device how large > it is? OK, that was the wrong choice of words, on my part. I meant for sake of "nobleness". I calculated as a programmer that these are aligned do I make the extra effort of stating that in code, or I get lazy because it does not matter? > How much overhead do you think is incurred by the unaligned code > if the data happens to be aligned? > Well for BE systems we are already order of magnitude faster by just using the accessors, so I guess we are already well in the "plus" ;) This is such a small matter, sorry to bother you about it. Just that it's a programming style I'm constantly debating with myself, feel free to ignore it. The patch looks very good to me as it is. Thanks Boaz