From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754278Ab3AaFmn (ORCPT ); Thu, 31 Jan 2013 00:42:43 -0500 Received: from mga14.intel.com ([143.182.124.37]:21628 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751628Ab3AaFml (ORCPT ); Thu, 31 Jan 2013 00:42:41 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,574,1355126400"; d="scan'208";a="196939128" Date: Thu, 31 Jan 2013 13:43:24 +0800 From: Aaron Lu To: Alan Stern Cc: Jens Axboe , "Rafael J. Wysocki" , James Bottomley , linux-pm@vger.kernel.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Aaron Lu , Shane Huang Subject: Re: [PATCH v8 4/4] sd: change to auto suspend mode Message-ID: <20130131054324.GB14627@aaronlu.sh.intel.com> References: <1359538494-2936-5-git-send-email-aaron.lu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 30, 2013 at 10:38:26AM -0500, Alan Stern wrote: > On Wed, 30 Jan 2013, Aaron Lu wrote: > > > From: Lin Ming > > > > Uses block layer runtime pm helper functions in > > scsi_runtime_suspend/resume for devices that take advantage of it. > > > > Remove scsi_autopm_* from sd open/release path and check_events path. > > > > Signed-off-by: Lin Ming > > Signed-off-by: Aaron Lu > > A couple of very minor suggestions... > > > --- a/drivers/scsi/scsi_pm.c > > +++ b/drivers/scsi/scsi_pm.c > > > @@ -144,18 +144,44 @@ static int scsi_bus_restore(struct device *dev) > > > > #ifdef CONFIG_PM_RUNTIME > > > > +static int scsi_blk_runtime_suspend(struct device *dev) > > +{ > > + struct scsi_device *sdev = to_scsi_device(dev); > > For this routine and the other new ones, it may be slightly more > efficient to pass both dev and sdev as arguments (this depends on how > smart the compiler's optimizer is). The caller already knows both of > them, after all. What about passing only scsi_device? When device is needed, I can use &sdev->sdev_gendev. Is this equally efficient? > > static int scsi_runtime_suspend(struct device *dev) > > { > > int err = 0; > > - const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; > > > > dev_dbg(dev, "scsi_runtime_suspend\n"); > > if (scsi_is_sdev_device(dev)) { > > - err = scsi_dev_type_suspend(dev, > > - pm ? pm->runtime_suspend : NULL); > > - if (err == -EAGAIN) > > - pm_schedule_suspend(dev, jiffies_to_msecs( > > - round_jiffies_up_relative(HZ/10))); > > + struct scsi_device *sdev = to_scsi_device(dev); > > There should be a blank line between the declaration and the > executable code. OK, will change this. > > @@ -185,10 +233,17 @@ static int scsi_runtime_idle(struct device *dev) > > > > /* Insert hooks here for targets, hosts, and transport classes */ > > > > - if (scsi_is_sdev_device(dev)) > > - err = pm_schedule_suspend(dev, 100); > > - else > > + if (scsi_is_sdev_device(dev)) { > > + struct scsi_device *sdev = to_scsi_device(dev); > > Blank line. > > > + if (sdev->request_queue->dev) { > > + pm_runtime_mark_last_busy(dev); > > + err = pm_runtime_autosuspend(dev); > > + } else { > > + err = pm_schedule_suspend(dev, 100); > > + } > > + } else { > > err = pm_runtime_suspend(dev); > > + } > > return err; Shall we ignore the return value for these pm_xxx_suspend functions? I mean we do not need to record the return value for them and return it, since pm core doesn't care the return value of idle callback. Thanks, Aaron