mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-27 06:34:11 +08:00
e5248a111b
Prevent automatic system suspend from happening during system shutdown by making try_to_suspend() check system_state and return immediately if it is not SYSTEM_RUNNING. This prevents the following breakage from happening (scenario from Zhang Yanmin): Kernel starts shutdown and calls all device driver's shutdown callback. When a driver's shutdown is called, the last wakelock is released and suspend-to-ram starts. However, as some driver's shut down callbacks already shut down devices and disabled runtime pm, the suspend-to-ram calls driver's suspend callback without noticing that device is already off and causes crash. [rjw: Changelog] Signed-off-by: Liu ShuoX <shuox.liu@intel.com> Cc: 3.5+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
129 lines
2.6 KiB
C
129 lines
2.6 KiB
C
/*
|
|
* kernel/power/autosleep.c
|
|
*
|
|
* Opportunistic sleep support.
|
|
*
|
|
* Copyright (C) 2012 Rafael J. Wysocki <rjw@sisk.pl>
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/pm_wakeup.h>
|
|
|
|
#include "power.h"
|
|
|
|
static suspend_state_t autosleep_state;
|
|
static struct workqueue_struct *autosleep_wq;
|
|
/*
|
|
* Note: it is only safe to mutex_lock(&autosleep_lock) if a wakeup_source
|
|
* is active, otherwise a deadlock with try_to_suspend() is possible.
|
|
* Alternatively mutex_lock_interruptible() can be used. This will then fail
|
|
* if an auto_sleep cycle tries to freeze processes.
|
|
*/
|
|
static DEFINE_MUTEX(autosleep_lock);
|
|
static struct wakeup_source *autosleep_ws;
|
|
|
|
static void try_to_suspend(struct work_struct *work)
|
|
{
|
|
unsigned int initial_count, final_count;
|
|
|
|
if (!pm_get_wakeup_count(&initial_count, true))
|
|
goto out;
|
|
|
|
mutex_lock(&autosleep_lock);
|
|
|
|
if (!pm_save_wakeup_count(initial_count) ||
|
|
system_state != SYSTEM_RUNNING) {
|
|
mutex_unlock(&autosleep_lock);
|
|
goto out;
|
|
}
|
|
|
|
if (autosleep_state == PM_SUSPEND_ON) {
|
|
mutex_unlock(&autosleep_lock);
|
|
return;
|
|
}
|
|
if (autosleep_state >= PM_SUSPEND_MAX)
|
|
hibernate();
|
|
else
|
|
pm_suspend(autosleep_state);
|
|
|
|
mutex_unlock(&autosleep_lock);
|
|
|
|
if (!pm_get_wakeup_count(&final_count, false))
|
|
goto out;
|
|
|
|
/*
|
|
* If the wakeup occured for an unknown reason, wait to prevent the
|
|
* system from trying to suspend and waking up in a tight loop.
|
|
*/
|
|
if (final_count == initial_count)
|
|
schedule_timeout_uninterruptible(HZ / 2);
|
|
|
|
out:
|
|
queue_up_suspend_work();
|
|
}
|
|
|
|
static DECLARE_WORK(suspend_work, try_to_suspend);
|
|
|
|
void queue_up_suspend_work(void)
|
|
{
|
|
if (autosleep_state > PM_SUSPEND_ON)
|
|
queue_work(autosleep_wq, &suspend_work);
|
|
}
|
|
|
|
suspend_state_t pm_autosleep_state(void)
|
|
{
|
|
return autosleep_state;
|
|
}
|
|
|
|
int pm_autosleep_lock(void)
|
|
{
|
|
return mutex_lock_interruptible(&autosleep_lock);
|
|
}
|
|
|
|
void pm_autosleep_unlock(void)
|
|
{
|
|
mutex_unlock(&autosleep_lock);
|
|
}
|
|
|
|
int pm_autosleep_set_state(suspend_state_t state)
|
|
{
|
|
|
|
#ifndef CONFIG_HIBERNATION
|
|
if (state >= PM_SUSPEND_MAX)
|
|
return -EINVAL;
|
|
#endif
|
|
|
|
__pm_stay_awake(autosleep_ws);
|
|
|
|
mutex_lock(&autosleep_lock);
|
|
|
|
autosleep_state = state;
|
|
|
|
__pm_relax(autosleep_ws);
|
|
|
|
if (state > PM_SUSPEND_ON) {
|
|
pm_wakep_autosleep_enabled(true);
|
|
queue_up_suspend_work();
|
|
} else {
|
|
pm_wakep_autosleep_enabled(false);
|
|
}
|
|
|
|
mutex_unlock(&autosleep_lock);
|
|
return 0;
|
|
}
|
|
|
|
int __init pm_autosleep_init(void)
|
|
{
|
|
autosleep_ws = wakeup_source_register("autosleep");
|
|
if (!autosleep_ws)
|
|
return -ENOMEM;
|
|
|
|
autosleep_wq = alloc_ordered_workqueue("autosleep", 0);
|
|
if (autosleep_wq)
|
|
return 0;
|
|
|
|
wakeup_source_unregister(autosleep_ws);
|
|
return -ENOMEM;
|
|
}
|