From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755068Ab1ILVuk (ORCPT ); Mon, 12 Sep 2011 17:50:40 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:58722 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754931Ab1ILVui (ORCPT ); Mon, 12 Sep 2011 17:50:38 -0400 From: "Rafael J. Wysocki" To: Ming Lei Subject: Re: [PATCH 2/5] PM / Runtime: Do not run callbacks under lock for power.irq_safe set Date: Mon, 12 Sep 2011 23:52:39 +0200 User-Agent: KMail/1.13.6 (Linux/3.1.0-rc4+; KDE/4.6.0; x86_64; ; ) Cc: Linux PM mailing list , LKML , "Linux-sh list" , Magnus Damm , Kevin Hilman , jean.pihet@newoldbits.com References: <201108310017.03103.rjw@sisk.pl> <201108310020.26104.rjw@sisk.pl> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201109122352.39848.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Monday, September 12, 2011, Ming Lei wrote: > Hi, > > On Wed, Aug 31, 2011 at 6:20 AM, Rafael J. Wysocki wrote: > > 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 > > If power.lock is released, the transition states(resuming or suspending) > may be observed in rpm_suspend or rpm_resume, then tasks schedule > will be produced in these two functions, I don't think so, because the interrupts are still off. > so the functions below can't be > > pm_runtime_suspend() > pm_runtime_autosuspend() > pm_runtime_resume() > pm_runtime_put_sync_suspend() > pm_runtime_put_sync_autosuspend() > > called in irq-off contexts safely even though irq_safe flag is set. The patch doesn't cause rpm_suspend() and rpm_resume() to turn interrupts on if irq_safe is set, it only causes them to release the lock (temporarily). Thanks, Rafael