From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933123Ab2C1VYq (ORCPT ); Wed, 28 Mar 2012 17:24:46 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:40786 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758787Ab2C1VXI (ORCPT ); Wed, 28 Mar 2012 17:23:08 -0400 From: "Rafael J. Wysocki" To: linux-kernel@vger.kernel.org Subject: [PATCH v2 5/8] PM / Sleep: Move disabling of usermode helpers to the freezer Date: Wed, 28 Mar 2012 23:23:49 +0200 User-Agent: KMail/1.13.6 (Linux/3.3.0+; KDE/4.6.0; x86_64; ; ) Cc: Stephen Boyd , Linus Torvalds , Saravana Kannan , Kay Sievers , Greg KH , Christian Lamparter , "Srivatsa S. Bhat" , alan@lxorguk.ukuu.org.uk, Linux PM mailing list References: <201203032122.36745.chunkeey@googlemail.com> <201203260000.34377.rjw@sisk.pl> <201203282319.54708.rjw@sisk.pl> In-Reply-To: <201203282319.54708.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201203282323.50123.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 core suspend/hibernation code calls usermodehelper_disable() to avoid race conditions between the freezer and the starting of usermode helpers and each code path has to do that on its own. However, it is always called right before freeze_processes() and usermodehelper_enable() is always called right after thaw_processes(). For this reason, to avoid code duplication and to make the connection between usermodehelper_disable() and the freezer more visible, make freeze_processes() call it and remove the direct usermodehelper_disable() and usermodehelper_enable() calls from all suspend/hibernation code paths. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman --- kernel/power/hibernate.c | 11 ----------- kernel/power/process.c | 7 +++++++ kernel/power/suspend.c | 7 ------- kernel/power/user.c | 10 +--------- 4 files changed, 8 insertions(+), 27 deletions(-) Index: linux/kernel/power/process.c =================================================================== --- linux.orig/kernel/power/process.c +++ linux/kernel/power/process.c @@ -16,6 +16,7 @@ #include #include #include +#include /* * Timeout for stopping processes @@ -122,6 +123,10 @@ int freeze_processes(void) { int error; + error = usermodehelper_disable(); + if (error) + return error; + if (!pm_freezing) atomic_inc(&system_freezing_cnt); @@ -187,6 +192,8 @@ void thaw_processes(void) } while_each_thread(g, p); read_unlock(&tasklist_lock); + usermodehelper_enable(); + schedule(); printk("done.\n"); } Index: linux/kernel/power/suspend.c =================================================================== --- linux.orig/kernel/power/suspend.c +++ linux/kernel/power/suspend.c @@ -12,7 +12,6 @@ #include #include #include -#include #include #include #include @@ -102,17 +101,12 @@ static int suspend_prepare(void) if (error) goto Finish; - error = usermodehelper_disable(); - if (error) - goto Finish; - error = suspend_freeze_processes(); if (!error) return 0; suspend_stats.failed_freeze++; dpm_save_failed_step(SUSPEND_FREEZE); - usermodehelper_enable(); Finish: pm_notifier_call_chain(PM_POST_SUSPEND); pm_restore_console(); @@ -259,7 +253,6 @@ int suspend_devices_and_enter(suspend_st static void suspend_finish(void) { suspend_thaw_processes(); - usermodehelper_enable(); pm_notifier_call_chain(PM_POST_SUSPEND); pm_restore_console(); } Index: linux/kernel/power/hibernate.c =================================================================== --- linux.orig/kernel/power/hibernate.c +++ linux/kernel/power/hibernate.c @@ -16,7 +16,6 @@ #include #include #include -#include #include #include #include @@ -620,10 +619,6 @@ int hibernate(void) sys_sync(); printk("done.\n"); - error = usermodehelper_disable(); - if (error) - goto Exit; - error = freeze_processes(); if (error) goto Free_bitmaps; @@ -660,7 +655,6 @@ int hibernate(void) freezer_test_done = false; Free_bitmaps: - usermodehelper_enable(); free_basic_memory_bitmaps(); Exit: pm_notifier_call_chain(PM_POST_HIBERNATION); @@ -780,10 +774,6 @@ static int software_resume(void) if (error) goto close_finish; - error = usermodehelper_disable(); - if (error) - goto close_finish; - pr_debug("PM: Preparing processes for restore.\n"); error = freeze_processes(); if (error) { @@ -802,7 +792,6 @@ static int software_resume(void) swsusp_free(); thaw_processes(); Done: - usermodehelper_enable(); free_basic_memory_bitmaps(); Finish: pm_notifier_call_chain(PM_POST_RESTORE); Index: linux/kernel/power/user.c =================================================================== --- linux.orig/kernel/power/user.c +++ linux/kernel/power/user.c @@ -12,7 +12,6 @@ #include #include #include -#include #include #include #include @@ -222,14 +221,8 @@ static long snapshot_ioctl(struct file * sys_sync(); printk("done.\n"); - error = usermodehelper_disable(); - if (error) - break; - error = freeze_processes(); - if (error) - usermodehelper_enable(); - else + if (!error) data->frozen = 1; break; @@ -238,7 +231,6 @@ static long snapshot_ioctl(struct file * break; pm_restore_gfp_mask(); thaw_processes(); - usermodehelper_enable(); data->frozen = 0; break;