From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753045Ab1H3WV0 (ORCPT ); Tue, 30 Aug 2011 18:21:26 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:49763 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752662Ab1H3WVN (ORCPT ); Tue, 30 Aug 2011 18:21:13 -0400 From: "Rafael J. Wysocki" To: Linux PM mailing list Subject: [PATCH 2/5] PM / Runtime: Do not run callbacks under lock for power.irq_safe set Date: Wed, 31 Aug 2011 00:20:25 +0200 User-Agent: KMail/1.13.6 (Linux/3.1.0-rc4+; KDE/4.6.0; x86_64; ; ) Cc: LKML , "Linux-sh list" , Magnus Damm , Kevin Hilman , jean.pihet@newoldbits.com References: <201108310017.03103.rjw@sisk.pl> In-Reply-To: <201108310017.03103.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201108310020.26104.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki The rpm_suspend() and rpm_resume() routines execute subsystem or PM domain callbacks under power.lock if power.irq_safe is set for the given device. This is inconsistent with that rpm_idle() does after commit 02b2677 (PM / Runtime: Allow _put_sync() from interrupts-disabled context) and is problematic for subsystems and PM domains wanting to use power.lock for synchronization in their runtime PM callbacks. For this reason, make runtime PM core functions always release power.lock before invoking subsystem or PM domain callbacks. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/runtime.c | 50 ++++++++++++++++++++++++------------------- 1 file changed, 28 insertions(+), 22 deletions(-) Index: linux/drivers/base/power/runtime.c =================================================================== --- linux.orig/drivers/base/power/runtime.c +++ linux/drivers/base/power/runtime.c @@ -155,6 +155,31 @@ static int rpm_check_suspend_allowed(str } /** + * __rpm_callback - Run a given runtime PM callback for a given device. + * @cb: Runtime PM callback to run. + * @dev: Device to run the callback for. + */ +static int __rpm_callback(int (*cb)(struct device *), struct device *dev) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + int retval; + + if (dev->power.irq_safe) + spin_unlock(&dev->power.lock); + else + spin_unlock_irq(&dev->power.lock); + + retval = cb(dev); + + if (dev->power.irq_safe) + spin_lock(&dev->power.lock); + else + spin_lock_irq(&dev->power.lock); + + return retval; +} + +/** * rpm_idle - Notify device bus type if the device can be suspended. * @dev: Device to notify the bus type about. * @rpmflags: Flag bits. @@ -225,19 +250,8 @@ static int rpm_idle(struct device *dev, else callback = NULL; - if (callback) { - if (dev->power.irq_safe) - spin_unlock(&dev->power.lock); - else - spin_unlock_irq(&dev->power.lock); - - callback(dev); - - if (dev->power.irq_safe) - spin_lock(&dev->power.lock); - else - spin_lock_irq(&dev->power.lock); - } + if (callback) + __rpm_callback(callback, dev); dev->power.idle_notification = false; wake_up_all(&dev->power.wait_queue); @@ -252,22 +266,14 @@ static int rpm_idle(struct device *dev, * @dev: Device to run the callback for. */ static int rpm_callback(int (*cb)(struct device *), struct device *dev) - __releases(&dev->power.lock) __acquires(&dev->power.lock) { int retval; if (!cb) return -ENOSYS; - if (dev->power.irq_safe) { - retval = cb(dev); - } else { - spin_unlock_irq(&dev->power.lock); - - retval = cb(dev); + retval = __rpm_callback(cb, dev); - spin_lock_irq(&dev->power.lock); - } dev->power.runtime_error = retval; return retval != -EACCES ? retval : -EIO; }