Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934906Ab0KQQLW (ORCPT ); Wed, 17 Nov 2010 11:11:22 -0500 Received: from cantor2.suse.de ([195.135.220.15]:41471 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934741Ab0KQQLV (ORCPT ); Wed, 17 Nov 2010 11:11:21 -0500 Subject: Re: [PATCH] libata: remove unlock+relock cycle in ata_scsi_queuecmd From: James Bottomley To: Christoph Hellwig Cc: Jeff Garzik , Linus Torvalds , linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org, LKML , Tejun Heo In-Reply-To: <20101117154741.GA16768@infradead.org> References: <20101117062958.GA2894@havoc.gtf.org> <4CE38D70.4010507@garzik.org> <1290007719.4736.9.camel@mulgrave.site> <20101117154741.GA16768@infradead.org> Content-Type: text/plain; charset="UTF-8" Date: Wed, 17 Nov 2010 10:11:16 -0600 Message-ID: <1290010276.4736.51.camel@mulgrave.site> Mime-Version: 1.0 X-Mailer: Evolution 2.30.1.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1420 Lines: 30 On Wed, 2010-11-17 at 10:47 -0500, Christoph Hellwig wrote: > > Right ... I couldn't persuade anyone else to do it, so I'll probably end > > up coding it. It looks like the serial number zero check might be > > bogus. If so I'll remove it, then push the serial number acquisition > > down only into the locked queuecommand of only those drivers that > > actually use it (which were listed in the quoted email, and which might > > have a big impetus to remove it if the use is trivial). Then we can > > begin unwinding the locking. > > In dc395x, eata_pio, in2000, lpfc, megaraid_legacy, megaraid_mbox, > megaraid_sas, mesh, ncr53c8xx, qla1280, qla4xxx, wd33c93 and i2o_scsi > use it in printks only, and all this can be safely removed. > > Except for EH that only leaves dpt_i2o, eata, mpt2sas, u14-34f, mptscsi > as non-trivial users. If you sort out the EH side I'll volunteer to > kill the printks and add private serial numbers to the five drivers > mentioned above. You're on (you were cc'd on the patch) ... I was planning just to move the scsi_cmnd_get_serial() call into the locked queuecommand routine, but a more permanent solution might be better. James -- 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/