From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH 1/3] target: simplify cmd transformation Date: Wed, 17 Nov 2010 17:32:07 -0500 Message-ID: <20101117223207.GC26760@infradead.org> References: <20101117213847.GA26557@infradead.org> <1290032519.31890.56.camel@haakon2.linux-iscsi.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:49033 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935471Ab0KQWcI (ORCPT ); Wed, 17 Nov 2010 17:32:08 -0500 Content-Disposition: inline In-Reply-To: <1290032519.31890.56.camel@haakon2.linux-iscsi.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Nicholas A. Bellinger" Cc: Christoph Hellwig , linux-scsi@vger.kernel.org On Wed, Nov 17, 2010 at 02:21:59PM -0800, Nicholas A. Bellinger wrote: > On Wed, 2010-11-17 at 16:38 -0500, Christoph Hellwig wrote: > > There is no need for the transport_cdb_transform function pointer, > > we can simply call the right code based on the cmd flags. > > > > Signed-off-by: Christoph Hellwig > > > > Hmmm, it is really less expensive to drop cmd->transport_cdb_transport() > and change transport_generic_new_cmd() to require 4 bitwise AND instructions > for each bulk SCF_SCSI_DATA_SG_IO_CDB cmd..? The pointer bloats every single command in flight, and CPU time is getting really cheap these days. Either way this will get much simpler after a few more patches. See the next one for a first preview.