From 51d6ff7acd920379f54d0be4dbe844a46178a65f Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Sat, 4 Feb 2012 22:26:38 +0100 Subject: PM / Hibernate: Thaw kernel threads in hibernation_snapshot() in error/test path In the hibernation call path, the kernel threads are frozen inside hibernation_snapshot(). If we happen to encounter an error further down the road or if we are exiting early due to a successful freezer test, then thaw kernel threads before returning to the caller. Signed-off-by: Srivatsa S. Bhat Acked-by: Tejun Heo Signed-off-by: Rafael J. Wysocki --- kernel/power/user.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'kernel/power/user.c') diff --git a/kernel/power/user.c b/kernel/power/user.c index 3e100075b13c..7bee91f9af51 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -249,16 +249,12 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, } pm_restore_gfp_mask(); error = hibernation_snapshot(data->platform_support); - if (error) { - thaw_kernel_threads(); - } else { + if (!error) { error = put_user(in_suspend, (int __user *)arg); if (!error && !freezer_test_done) data->ready = 1; - if (freezer_test_done) { + if (freezer_test_done) freezer_test_done = false; - thaw_kernel_threads(); - } } break; -- cgit v1.2.3-59-g8ed1b From a556d5b58345ccf51826b9ceac078072f830738b Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Sat, 4 Feb 2012 23:39:56 +0100 Subject: PM / Hibernate: Refactor and simplify freezer_test_done The code related to 'freezer_test_done' is needlessly convoluted. Refactor the code and simplify the implementation. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 10 +++++----- kernel/power/user.c | 6 ++---- 2 files changed, 7 insertions(+), 9 deletions(-) (limited to 'kernel/power/user.c') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index c6dee739080c..72baaf011fb7 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -629,12 +629,8 @@ int hibernate(void) goto Finish; error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM); - if (error) - goto Thaw; - if (freezer_test_done) { - freezer_test_done = false; + if (error || freezer_test_done) goto Thaw; - } if (in_suspend) { unsigned int flags = 0; @@ -659,6 +655,10 @@ int hibernate(void) Thaw: thaw_processes(); + + /* Don't bother checking whether freezer_test_done is true */ + freezer_test_done = false; + Finish: free_basic_memory_bitmaps(); usermodehelper_enable(); diff --git a/kernel/power/user.c b/kernel/power/user.c index 7bee91f9af51..33c4329205af 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -251,10 +251,8 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, error = hibernation_snapshot(data->platform_support); if (!error) { error = put_user(in_suspend, (int __user *)arg); - if (!error && !freezer_test_done) - data->ready = 1; - if (freezer_test_done) - freezer_test_done = false; + data->ready = !freezer_test_done && !error; + freezer_test_done = false; } break; -- cgit v1.2.3-59-g8ed1b From 1e73203cd1157a03facc41ffb54050f5b28e55bd Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 28 Mar 2012 23:30:21 +0200 Subject: PM / Sleep: Move disabling of usermode helpers to the freezer 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 Cc: stable@vger.kernel.org --- 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(-) (limited to 'kernel/power/user.c') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 639ff6e4ae9e..e09dfbfeecee 100644 --- a/kernel/power/hibernate.c +++ b/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); diff --git a/kernel/power/process.c b/kernel/power/process.c index 0d2aeb226108..56eaac7e88ab 100644 --- a/kernel/power/process.c +++ b/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"); } diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 88e5c967370d..396d262b8fd0 100644 --- a/kernel/power/suspend.c +++ b/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_state_t state) static void suspend_finish(void) { suspend_thaw_processes(); - usermodehelper_enable(); pm_notifier_call_chain(PM_POST_SUSPEND); pm_restore_console(); } diff --git a/kernel/power/user.c b/kernel/power/user.c index 33c4329205af..91b0fd021a95 100644 --- a/kernel/power/user.c +++ b/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 *filp, unsigned int cmd, 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 *filp, unsigned int cmd, break; pm_restore_gfp_mask(); thaw_processes(); - usermodehelper_enable(); data->frozen = 0; break; -- cgit v1.2.3-59-g8ed1b