Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755254Ab0LTJj0 (ORCPT ); Mon, 20 Dec 2010 04:39:26 -0500 Received: from mail.linux-iscsi.org ([67.23.28.174]:60739 "EHLO linux-iscsi.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755098Ab0LTJjZ (ORCPT ); Mon, 20 Dec 2010 04:39:25 -0500 Subject: Re: [PATCH 03/12] libsas: Convert to host_lock less w/ interrupts disabled externally From: "Nicholas A. Bellinger" To: Boaz Harrosh Cc: linux-iscsi-target-dev@googlegroups.com, linux-scsi , linux-kernel , James Bottomley , Jeff Garzik , Christoph Hellwig , FUJITA Tomonori , Hannes Reinecke , Mike Christie , Mike Anderson , Tejun Heo , Vasu Dev , Tim Chen , Andi Kleen , Ravi Anand , Andrew Vasquez , Joe Eykholt , James Smart , Douglas Gilbert , adam radford , Kashyap Desai , MPTFusionLinux In-Reply-To: <4D0F1A99.8000703@panasas.com> References: <1292793727-31957-1-git-send-email-nab@linux-iscsi.org> <1292793727-31957-4-git-send-email-nab@linux-iscsi.org> <4D0F1A99.8000703@panasas.com> Content-Type: text/plain Date: Mon, 20 Dec 2010 01:33:26 -0800 Message-Id: <1292837606.20840.52.camel@haakon2.linux-iscsi.org> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2859 Lines: 80 On Mon, 2010-12-20 at 10:58 +0200, Boaz Harrosh wrote: > On 12/19/2010 11:21 PM, Nicholas A. Bellinger wrote: > > From: Nicholas Bellinger > > > > This patch converts the libsas queuecommand to run in host_lock less mode > > w/ the new IRQ_DISABLE_SCSI_QCMD() that disables interrupts while calling > > ->queuecommand() dispatch. > > > > Signed-off-by: Nicholas A. Bellinger > > --- > > drivers/scsi/libsas/sas_scsi_host.c | 12 ++---------- > > 1 files changed, 2 insertions(+), 10 deletions(-) > > > > diff --git a/drivers/scsi/libsas/sas_scsi_host.c b/drivers/scsi/libsas/sas_scsi_host.c > > index 29251fa..011580f 100644 > > --- a/drivers/scsi/libsas/sas_scsi_host.c > > +++ b/drivers/scsi/libsas/sas_scsi_host.c > > @@ -185,24 +185,17 @@ int sas_queue_up(struct sas_task *task) > > /** > > * sas_queuecommand -- Enqueue a command for processing > > * @parameters: See SCSI Core documentation > > - * > > - * Note: XXX: Remove the host unlock/lock pair when SCSI Core can > > - * call us without holding an IRQ spinlock... > > */ > > -static int sas_queuecommand_lck(struct scsi_cmnd *cmd, > > +static int sas_queuecommand_irq_disable(struct scsi_cmnd *cmd, > > void (*scsi_done)(struct scsi_cmnd *)) > > - __releases(host->host_lock) > > __acquires(dev->sata_dev.ap->lock) > > __releases(dev->sata_dev.ap->lock) > > - __acquires(host->host_lock) > > { > > int res = 0; > > struct domain_device *dev = cmd_to_domain_dev(cmd); > > struct Scsi_Host *host = cmd->device->host; > > struct sas_internal *i = to_sas_internal(host->transportt); > > > > - spin_unlock_irq(host->host_lock); > > - > > { > > struct sas_ha_struct *sas_ha = dev->port->ha; > > struct sas_task *task; > > @@ -250,11 +243,10 @@ static int sas_queuecommand_lck(struct scsi_cmnd *cmd, > > } > > } > > out: > > - spin_lock_irq(host->host_lock); > > return res; > > } > > > > -DEF_SCSI_QCMD(sas_queuecommand) > > +IRQ_DISABLE_SCSI_QCMD(sas_queuecommand) > > > > I hate this new macro. It is so simple by now. And anyway you are > doing them one by one and auditing the code. Please completely drop > this macro and open code it. There is no "safety" argument to this > ugliness, any more. > > (Completely drop the [PATCH 02/12] scsi: Add IRQ_DISABLE_SCSI_QCMD wrapper > patch and redo the users) > Hi Boaz, I am happy to open code the handful of remaining LLDs that need proper conversion for lock_less-LLDs-for-38-v4 and drop patch #2 now that we have isolated the first round of host_lock-less LLD conversions. Best Regards, --nab -- 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/