PM / Wakeup: Introduce wakeup source objects and event statistics (v3)

Introduce struct wakeup_source for representing system wakeup sources
within the kernel and for collecting statistics related to them.
Make the recently introduced helper functions pm_wakeup_event(),
pm_stay_awake() and pm_relax() use struct wakeup_source objects
internally, so that wakeup statistics associated with wakeup devices
can be collected and reported in a consistent way (the definition of
pm_relax() is changed, which is harmless, because this function is
not called directly by anyone yet).  Introduce new wakeup-related
sysfs device attributes in /sys/devices/.../power for reporting the
device wakeup statistics.

Change the global wakeup events counters event_count and
events_in_progress into atomic variables, so that it is not necessary
to acquire a global spinlock in pm_wakeup_event(), pm_stay_awake()
and pm_relax(), which should allow us to avoid lock contention in
these functions on SMP systems with many wakeup devices.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Rafael J. Wysocki 2010-09-22 22:09:10 +02:00
parent 0702d9ee0f
commit 074037ec79
10 changed files with 762 additions and 131 deletions

View file

@ -77,3 +77,73 @@ Description:
devices this attribute is set to "enabled" by bus type code or
device drivers and in that cases it should be safe to leave the
default value.
What: /sys/devices/.../power/wakeup_count
Date: September 2010
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/devices/.../wakeup_count attribute contains the number
of signaled wakeup events associated with the device. This
attribute is read-only. If the device is not enabled to wake up
the system from sleep states, this attribute is empty.
What: /sys/devices/.../power/wakeup_active_count
Date: September 2010
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/devices/.../wakeup_active_count attribute contains the
number of times the processing of wakeup events associated with
the device was completed (at the kernel level). This attribute
is read-only. If the device is not enabled to wake up the
system from sleep states, this attribute is empty.
What: /sys/devices/.../power/wakeup_hit_count
Date: September 2010
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/devices/.../wakeup_hit_count attribute contains the
number of times the processing of a wakeup event associated with
the device might prevent the system from entering a sleep state.
This attribute is read-only. If the device is not enabled to
wake up the system from sleep states, this attribute is empty.
What: /sys/devices/.../power/wakeup_active
Date: September 2010
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/devices/.../wakeup_active attribute contains either 1,
or 0, depending on whether or not a wakeup event associated with
the device is being processed (1). This attribute is read-only.
If the device is not enabled to wake up the system from sleep
states, this attribute is empty.
What: /sys/devices/.../power/wakeup_total_time_ms
Date: September 2010
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/devices/.../wakeup_total_time_ms attribute contains
the total time of processing wakeup events associated with the
device, in milliseconds. This attribute is read-only. If the
device is not enabled to wake up the system from sleep states,
this attribute is empty.
What: /sys/devices/.../power/wakeup_max_time_ms
Date: September 2010
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/devices/.../wakeup_max_time_ms attribute contains
the maximum time of processing a single wakeup event associated
with the device, in milliseconds. This attribute is read-only.
If the device is not enabled to wake up the system from sleep
states, this attribute is empty.
What: /sys/devices/.../power/wakeup_last_time_ms
Date: September 2010
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/devices/.../wakeup_last_time_ms attribute contains
the value of the monotonic clock corresponding to the time of
signaling the last wakeup event associated with the device, in
milliseconds. This attribute is read-only. If the device is
not enabled to wake up the system from sleep states, this
attribute is empty.

View file

@ -60,7 +60,8 @@ void device_pm_init(struct device *dev)
dev->power.status = DPM_ON;
init_completion(&dev->power.completion);
complete_all(&dev->power.completion);
dev->power.wakeup_count = 0;
dev->power.wakeup = NULL;
spin_lock_init(&dev->power.lock);
pm_runtime_init(dev);
}
@ -120,6 +121,7 @@ void device_pm_remove(struct device *dev)
mutex_lock(&dpm_list_mtx);
list_del_init(&dev->power.entry);
mutex_unlock(&dpm_list_mtx);
device_wakeup_disable(dev);
pm_runtime_remove(dev);
}

View file

@ -34,6 +34,7 @@ extern void device_pm_move_last(struct device *);
static inline void device_pm_init(struct device *dev)
{
spin_lock_init(&dev->power.lock);
pm_runtime_init(dev);
}

View file

@ -1099,8 +1099,6 @@ EXPORT_SYMBOL_GPL(pm_runtime_allow);
*/
void pm_runtime_init(struct device *dev)
{
spin_lock_init(&dev->power.lock);
dev->power.runtime_status = RPM_SUSPENDED;
dev->power.idle_notification = false;

View file

@ -210,11 +210,122 @@ static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
static ssize_t wakeup_count_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%lu\n", dev->power.wakeup_count);
unsigned long count = 0;
bool enabled = false;
spin_lock_irq(&dev->power.lock);
if (dev->power.wakeup) {
count = dev->power.wakeup->event_count;
enabled = true;
}
spin_unlock_irq(&dev->power.lock);
return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
}
static DEVICE_ATTR(wakeup_count, 0444, wakeup_count_show, NULL);
#endif
static ssize_t wakeup_active_count_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned long count = 0;
bool enabled = false;
spin_lock_irq(&dev->power.lock);
if (dev->power.wakeup) {
count = dev->power.wakeup->active_count;
enabled = true;
}
spin_unlock_irq(&dev->power.lock);
return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
}
static DEVICE_ATTR(wakeup_active_count, 0444, wakeup_active_count_show, NULL);
static ssize_t wakeup_hit_count_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned long count = 0;
bool enabled = false;
spin_lock_irq(&dev->power.lock);
if (dev->power.wakeup) {
count = dev->power.wakeup->hit_count;
enabled = true;
}
spin_unlock_irq(&dev->power.lock);
return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
}
static DEVICE_ATTR(wakeup_hit_count, 0444, wakeup_hit_count_show, NULL);
static ssize_t wakeup_active_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned int active = 0;
bool enabled = false;
spin_lock_irq(&dev->power.lock);
if (dev->power.wakeup) {
active = dev->power.wakeup->active;
enabled = true;
}
spin_unlock_irq(&dev->power.lock);
return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n");
}
static DEVICE_ATTR(wakeup_active, 0444, wakeup_active_show, NULL);
static ssize_t wakeup_total_time_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
s64 msec = 0;
bool enabled = false;
spin_lock_irq(&dev->power.lock);
if (dev->power.wakeup) {
msec = ktime_to_ms(dev->power.wakeup->total_time);
enabled = true;
}
spin_unlock_irq(&dev->power.lock);
return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
}
static DEVICE_ATTR(wakeup_total_time_ms, 0444, wakeup_total_time_show, NULL);
static ssize_t wakeup_max_time_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
s64 msec = 0;
bool enabled = false;
spin_lock_irq(&dev->power.lock);
if (dev->power.wakeup) {
msec = ktime_to_ms(dev->power.wakeup->max_time);
enabled = true;
}
spin_unlock_irq(&dev->power.lock);
return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
}
static DEVICE_ATTR(wakeup_max_time_ms, 0444, wakeup_max_time_show, NULL);
static ssize_t wakeup_last_time_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
s64 msec = 0;
bool enabled = false;
spin_lock_irq(&dev->power.lock);
if (dev->power.wakeup) {
msec = ktime_to_ms(dev->power.wakeup->last_time);
enabled = true;
}
spin_unlock_irq(&dev->power.lock);
return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
}
static DEVICE_ATTR(wakeup_last_time_ms, 0444, wakeup_last_time_show, NULL);
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_PM_ADVANCED_DEBUG
#ifdef CONFIG_PM_RUNTIME
@ -288,6 +399,12 @@ static struct attribute * power_attrs[] = {
&dev_attr_wakeup.attr,
#ifdef CONFIG_PM_SLEEP
&dev_attr_wakeup_count.attr,
&dev_attr_wakeup_active_count.attr,
&dev_attr_wakeup_hit_count.attr,
&dev_attr_wakeup_active.attr,
&dev_attr_wakeup_total_time_ms.attr,
&dev_attr_wakeup_max_time_ms.attr,
&dev_attr_wakeup_last_time_ms.attr,
#endif
#ifdef CONFIG_PM_ADVANCED_DEBUG
&dev_attr_async.attr,

View file

@ -11,7 +11,10 @@
#include <linux/sched.h>
#include <linux/capability.h>
#include <linux/suspend.h>
#include <linux/pm.h>
#include "power.h"
#define TIMEOUT 100
/*
* If set, the suspend/hibernate code will abort transitions to a sleep state
@ -20,18 +23,244 @@
bool events_check_enabled;
/* The counter of registered wakeup events. */
static unsigned long event_count;
static atomic_t event_count = ATOMIC_INIT(0);
/* A preserved old value of event_count. */
static unsigned long saved_event_count;
static unsigned int saved_count;
/* The counter of wakeup events being processed. */
static unsigned long events_in_progress;
static atomic_t events_in_progress = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(events_lock);
static void pm_wakeup_timer_fn(unsigned long data);
static DEFINE_TIMER(events_timer, pm_wakeup_timer_fn, 0, 0);
static unsigned long events_timer_expires;
static LIST_HEAD(wakeup_sources);
/**
* wakeup_source_create - Create a struct wakeup_source object.
* @name: Name of the new wakeup source.
*/
struct wakeup_source *wakeup_source_create(const char *name)
{
struct wakeup_source *ws;
ws = kzalloc(sizeof(*ws), GFP_KERNEL);
if (!ws)
return NULL;
spin_lock_init(&ws->lock);
if (name)
ws->name = kstrdup(name, GFP_KERNEL);
return ws;
}
EXPORT_SYMBOL_GPL(wakeup_source_create);
/**
* wakeup_source_destroy - Destroy a struct wakeup_source object.
* @ws: Wakeup source to destroy.
*/
void wakeup_source_destroy(struct wakeup_source *ws)
{
if (!ws)
return;
spin_lock_irq(&ws->lock);
while (ws->active) {
spin_unlock_irq(&ws->lock);
schedule_timeout_interruptible(msecs_to_jiffies(TIMEOUT));
spin_lock_irq(&ws->lock);
}
spin_unlock_irq(&ws->lock);
kfree(ws->name);
kfree(ws);
}
EXPORT_SYMBOL_GPL(wakeup_source_destroy);
/**
* wakeup_source_add - Add given object to the list of wakeup sources.
* @ws: Wakeup source object to add to the list.
*/
void wakeup_source_add(struct wakeup_source *ws)
{
if (WARN_ON(!ws))
return;
setup_timer(&ws->timer, pm_wakeup_timer_fn, (unsigned long)ws);
ws->active = false;
spin_lock_irq(&events_lock);
list_add_rcu(&ws->entry, &wakeup_sources);
spin_unlock_irq(&events_lock);
synchronize_rcu();
}
EXPORT_SYMBOL_GPL(wakeup_source_add);
/**
* wakeup_source_remove - Remove given object from the wakeup sources list.
* @ws: Wakeup source object to remove from the list.
*/
void wakeup_source_remove(struct wakeup_source *ws)
{
if (WARN_ON(!ws))
return;
spin_lock_irq(&events_lock);
list_del_rcu(&ws->entry);
spin_unlock_irq(&events_lock);
synchronize_rcu();
}
EXPORT_SYMBOL_GPL(wakeup_source_remove);
/**
* wakeup_source_register - Create wakeup source and add it to the list.
* @name: Name of the wakeup source to register.
*/
struct wakeup_source *wakeup_source_register(const char *name)
{
struct wakeup_source *ws;
ws = wakeup_source_create(name);
if (ws)
wakeup_source_add(ws);
return ws;
}
EXPORT_SYMBOL_GPL(wakeup_source_register);
/**
* wakeup_source_unregister - Remove wakeup source from the list and remove it.
* @ws: Wakeup source object to unregister.
*/
void wakeup_source_unregister(struct wakeup_source *ws)
{
wakeup_source_remove(ws);
wakeup_source_destroy(ws);
}
EXPORT_SYMBOL_GPL(wakeup_source_unregister);
/**
* device_wakeup_attach - Attach a wakeup source object to a device object.
* @dev: Device to handle.
* @ws: Wakeup source object to attach to @dev.
*
* This causes @dev to be treated as a wakeup device.
*/
static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws)
{
spin_lock_irq(&dev->power.lock);
if (dev->power.wakeup) {
spin_unlock_irq(&dev->power.lock);
return -EEXIST;
}
dev->power.wakeup = ws;
spin_unlock_irq(&dev->power.lock);
return 0;
}
/**
* device_wakeup_enable - Enable given device to be a wakeup source.
* @dev: Device to handle.
*
* Create a wakeup source object, register it and attach it to @dev.
*/
int device_wakeup_enable(struct device *dev)
{
struct wakeup_source *ws;
int ret;
if (!dev || !dev->power.can_wakeup)
return -EINVAL;
ws = wakeup_source_register(dev_name(dev));
if (!ws)
return -ENOMEM;
ret = device_wakeup_attach(dev, ws);
if (ret)
wakeup_source_unregister(ws);
return ret;
}
EXPORT_SYMBOL_GPL(device_wakeup_enable);
/**
* device_wakeup_detach - Detach a device's wakeup source object from it.
* @dev: Device to detach the wakeup source object from.
*
* After it returns, @dev will not be treated as a wakeup device any more.
*/
static struct wakeup_source *device_wakeup_detach(struct device *dev)
{
struct wakeup_source *ws;
spin_lock_irq(&dev->power.lock);
ws = dev->power.wakeup;
dev->power.wakeup = NULL;
spin_unlock_irq(&dev->power.lock);
return ws;
}
/**
* device_wakeup_disable - Do not regard a device as a wakeup source any more.
* @dev: Device to handle.
*
* Detach the @dev's wakeup source object from it, unregister this wakeup source
* object and destroy it.
*/
int device_wakeup_disable(struct device *dev)
{
struct wakeup_source *ws;
if (!dev || !dev->power.can_wakeup)
return -EINVAL;
ws = device_wakeup_detach(dev);
if (ws)
wakeup_source_unregister(ws);
return 0;
}
EXPORT_SYMBOL_GPL(device_wakeup_disable);
/**
* device_init_wakeup - Device wakeup initialization.
* @dev: Device to handle.
* @enable: Whether or not to enable @dev as a wakeup device.
*
* By default, most devices should leave wakeup disabled. The exceptions are
* devices that everyone expects to be wakeup sources: keyboards, power buttons,
* possibly network interfaces, etc.
*/
int device_init_wakeup(struct device *dev, bool enable)
{
int ret = 0;
if (enable) {
device_set_wakeup_capable(dev, true);
ret = device_wakeup_enable(dev);
} else {
device_set_wakeup_capable(dev, false);
}
return ret;
}
EXPORT_SYMBOL_GPL(device_init_wakeup);
/**
* device_set_wakeup_enable - Enable or disable a device to wake up the system.
* @dev: Device to handle.
*/
int device_set_wakeup_enable(struct device *dev, bool enable)
{
if (!dev || !dev->power.can_wakeup)
return -EINVAL;
return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev);
}
EXPORT_SYMBOL_GPL(device_set_wakeup_enable);
/*
* The functions below use the observation that each wakeup event starts a
@ -55,118 +284,259 @@ static unsigned long events_timer_expires;
* knowledge, however, may not be available to it, so it can simply specify time
* to wait before the system can be suspended and pass it as the second
* argument of pm_wakeup_event().
*
* It is valid to call pm_relax() after pm_wakeup_event(), in which case the
* "no suspend" period will be ended either by the pm_relax(), or by the timer
* function executed when the timer expires, whichever comes first.
*/
/**
* wakup_source_activate - Mark given wakeup source as active.
* @ws: Wakeup source to handle.
*
* Update the @ws' statistics and, if @ws has just been activated, notify the PM
* core of the event by incrementing the counter of of wakeup events being
* processed.
*/
static void wakeup_source_activate(struct wakeup_source *ws)
{
ws->active = true;
ws->active_count++;
ws->timer_expires = jiffies;
ws->last_time = ktime_get();
atomic_inc(&events_in_progress);
}
/**
* __pm_stay_awake - Notify the PM core of a wakeup event.
* @ws: Wakeup source object associated with the source of the event.
*
* It is safe to call this function from interrupt context.
*/
void __pm_stay_awake(struct wakeup_source *ws)
{
unsigned long flags;
if (!ws)
return;
spin_lock_irqsave(&ws->lock, flags);
ws->event_count++;
if (!ws->active)
wakeup_source_activate(ws);
spin_unlock_irqrestore(&ws->lock, flags);
}
EXPORT_SYMBOL_GPL(__pm_stay_awake);
/**
* pm_stay_awake - Notify the PM core that a wakeup event is being processed.
* @dev: Device the wakeup event is related to.
*
* Notify the PM core of a wakeup event (signaled by @dev) by incrementing the
* counter of wakeup events being processed. If @dev is not NULL, the counter
* of wakeup events related to @dev is incremented too.
* Notify the PM core of a wakeup event (signaled by @dev) by calling
* __pm_stay_awake for the @dev's wakeup source object.
*
* Call this function after detecting of a wakeup event if pm_relax() is going
* to be called directly after processing the event (and possibly passing it to
* user space for further processing).
*
* It is safe to call this function from interrupt context.
*/
void pm_stay_awake(struct device *dev)
{
unsigned long flags;
spin_lock_irqsave(&events_lock, flags);
if (dev)
dev->power.wakeup_count++;
if (!dev)
return;
events_in_progress++;
spin_unlock_irqrestore(&events_lock, flags);
spin_lock_irqsave(&dev->power.lock, flags);
__pm_stay_awake(dev->power.wakeup);
spin_unlock_irqrestore(&dev->power.lock, flags);
}
EXPORT_SYMBOL_GPL(pm_stay_awake);
/**
* wakup_source_deactivate - Mark given wakeup source as inactive.
* @ws: Wakeup source to handle.
*
* Update the @ws' statistics and notify the PM core that the wakeup source has
* become inactive by decrementing the counter of wakeup events being processed
* and incrementing the counter of registered wakeup events.
*/
static void wakeup_source_deactivate(struct wakeup_source *ws)
{
ktime_t duration;
ktime_t now;
ws->relax_count++;
/*
* __pm_relax() may be called directly or from a timer function.
* If it is called directly right after the timer function has been
* started, but before the timer function calls __pm_relax(), it is
* possible that __pm_stay_awake() will be called in the meantime and
* will set ws->active. Then, ws->active may be cleared immediately
* by the __pm_relax() called from the timer function, but in such a
* case ws->relax_count will be different from ws->active_count.
*/
if (ws->relax_count != ws->active_count) {
ws->relax_count--;
return;
}
ws->active = false;
now = ktime_get();
duration = ktime_sub(now, ws->last_time);
ws->total_time = ktime_add(ws->total_time, duration);
if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time))
ws->max_time = duration;
del_timer(&ws->timer);
/*
* event_count has to be incremented before events_in_progress is
* modified, so that the callers of pm_check_wakeup_events() and
* pm_save_wakeup_count() don't see the old value of event_count and
* events_in_progress equal to zero at the same time.
*/
atomic_inc(&event_count);
smp_mb__before_atomic_dec();
atomic_dec(&events_in_progress);
}
/**
* pm_relax - Notify the PM core that processing of a wakeup event has ended.
*
* Notify the PM core that a wakeup event has been processed by decrementing
* the counter of wakeup events being processed and incrementing the counter
* of registered wakeup events.
* __pm_relax - Notify the PM core that processing of a wakeup event has ended.
* @ws: Wakeup source object associated with the source of the event.
*
* Call this function for wakeup events whose processing started with calling
* pm_stay_awake().
* __pm_stay_awake().
*
* It is safe to call it from interrupt context.
*/
void pm_relax(void)
void __pm_relax(struct wakeup_source *ws)
{
unsigned long flags;
spin_lock_irqsave(&events_lock, flags);
if (events_in_progress) {
events_in_progress--;
event_count++;
}
spin_unlock_irqrestore(&events_lock, flags);
if (!ws)
return;
spin_lock_irqsave(&ws->lock, flags);
if (ws->active)
wakeup_source_deactivate(ws);
spin_unlock_irqrestore(&ws->lock, flags);
}
EXPORT_SYMBOL_GPL(__pm_relax);
/**
* pm_relax - Notify the PM core that processing of a wakeup event has ended.
* @dev: Device that signaled the event.
*
* Execute __pm_relax() for the @dev's wakeup source object.
*/
void pm_relax(struct device *dev)
{
unsigned long flags;
if (!dev)
return;
spin_lock_irqsave(&dev->power.lock, flags);
__pm_relax(dev->power.wakeup);
spin_unlock_irqrestore(&dev->power.lock, flags);
}
EXPORT_SYMBOL_GPL(pm_relax);
/**
* pm_wakeup_timer_fn - Delayed finalization of a wakeup event.
* @data: Address of the wakeup source object associated with the event source.
*
* Decrease the counter of wakeup events being processed after it was increased
* by pm_wakeup_event().
* Call __pm_relax() for the wakeup source whose address is stored in @data.
*/
static void pm_wakeup_timer_fn(unsigned long data)
{
unsigned long flags;
spin_lock_irqsave(&events_lock, flags);
if (events_timer_expires
&& time_before_eq(events_timer_expires, jiffies)) {
events_in_progress--;
events_timer_expires = 0;
}
spin_unlock_irqrestore(&events_lock, flags);
__pm_relax((struct wakeup_source *)data);
}
/**
* __pm_wakeup_event - Notify the PM core of a wakeup event.
* @ws: Wakeup source object associated with the event source.
* @msec: Anticipated event processing time (in milliseconds).
*
* Notify the PM core of a wakeup event whose source is @ws that will take
* approximately @msec milliseconds to be processed by the kernel. If @ws is
* not active, activate it. If @msec is nonzero, set up the @ws' timer to
* execute pm_wakeup_timer_fn() in future.
*
* It is safe to call this function from interrupt context.
*/
void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec)
{
unsigned long flags;
unsigned long expires;
if (!ws)
return;
spin_lock_irqsave(&ws->lock, flags);
ws->event_count++;
if (!ws->active)
wakeup_source_activate(ws);
if (!msec) {
wakeup_source_deactivate(ws);
goto unlock;
}
expires = jiffies + msecs_to_jiffies(msec);
if (!expires)
expires = 1;
if (time_after(expires, ws->timer_expires)) {
mod_timer(&ws->timer, expires);
ws->timer_expires = expires;
}
unlock:
spin_unlock_irqrestore(&ws->lock, flags);
}
EXPORT_SYMBOL_GPL(__pm_wakeup_event);
/**
* pm_wakeup_event - Notify the PM core of a wakeup event.
* @dev: Device the wakeup event is related to.
* @msec: Anticipated event processing time (in milliseconds).
*
* Notify the PM core of a wakeup event (signaled by @dev) that will take
* approximately @msec milliseconds to be processed by the kernel. Increment
* the counter of registered wakeup events and (if @msec is nonzero) set up
* the wakeup events timer to execute pm_wakeup_timer_fn() in future (if the
* timer has not been set up already, increment the counter of wakeup events
* being processed). If @dev is not NULL, the counter of wakeup events related
* to @dev is incremented too.
*
* It is safe to call this function from interrupt context.
* Call __pm_wakeup_event() for the @dev's wakeup source object.
*/
void pm_wakeup_event(struct device *dev, unsigned int msec)
{
unsigned long flags;
spin_lock_irqsave(&events_lock, flags);
event_count++;
if (dev)
dev->power.wakeup_count++;
if (!dev)
return;
if (msec) {
unsigned long expires;
spin_lock_irqsave(&dev->power.lock, flags);
__pm_wakeup_event(dev->power.wakeup, msec);
spin_unlock_irqrestore(&dev->power.lock, flags);
}
EXPORT_SYMBOL_GPL(pm_wakeup_event);
expires = jiffies + msecs_to_jiffies(msec);
if (!expires)
expires = 1;
/**
* pm_wakeup_update_hit_counts - Update hit counts of all active wakeup sources.
*/
static void pm_wakeup_update_hit_counts(void)
{
unsigned long flags;
struct wakeup_source *ws;
if (!events_timer_expires
|| time_after(expires, events_timer_expires)) {
if (!events_timer_expires)
events_in_progress++;
mod_timer(&events_timer, expires);
events_timer_expires = expires;
}
rcu_read_lock();
list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
spin_lock_irqsave(&ws->lock, flags);
if (ws->active)
ws->hit_count++;
spin_unlock_irqrestore(&ws->lock, flags);
}
spin_unlock_irqrestore(&events_lock, flags);
rcu_read_unlock();
}
/**
@ -184,10 +554,13 @@ bool pm_check_wakeup_events(void)
spin_lock_irqsave(&events_lock, flags);
if (events_check_enabled) {
ret = (event_count == saved_event_count) && !events_in_progress;
ret = ((unsigned int)atomic_read(&event_count) == saved_count)
&& !atomic_read(&events_in_progress);
events_check_enabled = ret;
}
spin_unlock_irqrestore(&events_lock, flags);
if (!ret)
pm_wakeup_update_hit_counts();
return ret;
}
@ -202,24 +575,20 @@ bool pm_check_wakeup_events(void)
* drop down to zero has been interrupted by a signal (and the current number
* of wakeup events being processed is still nonzero). Otherwise return true.
*/
bool pm_get_wakeup_count(unsigned long *count)
bool pm_get_wakeup_count(unsigned int *count)
{
bool ret;
spin_lock_irq(&events_lock);
if (capable(CAP_SYS_ADMIN))
events_check_enabled = false;
while (events_in_progress && !signal_pending(current)) {
spin_unlock_irq(&events_lock);
schedule_timeout_interruptible(msecs_to_jiffies(100));
spin_lock_irq(&events_lock);
while (atomic_read(&events_in_progress) && !signal_pending(current)) {
pm_wakeup_update_hit_counts();
schedule_timeout_interruptible(msecs_to_jiffies(TIMEOUT));
}
*count = event_count;
ret = !events_in_progress;
spin_unlock_irq(&events_lock);
ret = !atomic_read(&events_in_progress);
*count = atomic_read(&event_count);
return ret;
}
@ -232,16 +601,19 @@ bool pm_get_wakeup_count(unsigned long *count)
* old number of registered wakeup events to be used by pm_check_wakeup_events()
* and return true. Otherwise return false.
*/
bool pm_save_wakeup_count(unsigned long count)
bool pm_save_wakeup_count(unsigned int count)
{
bool ret = false;
spin_lock_irq(&events_lock);
if (count == event_count && !events_in_progress) {
saved_event_count = count;
if (count == (unsigned int)atomic_read(&event_count)
&& !atomic_read(&events_in_progress)) {
saved_count = count;
events_check_enabled = true;
ret = true;
}
spin_unlock_irq(&events_lock);
if (!ret)
pm_wakeup_update_hit_counts();
return ret;
}

View file

@ -448,23 +448,24 @@ enum rpm_request {
RPM_REQ_RESUME,
};
struct wakeup_source;
struct dev_pm_info {
pm_message_t power_state;
unsigned int can_wakeup:1;
unsigned int should_wakeup:1;
unsigned async_suspend:1;
enum dpm_state status; /* Owned by the PM core */
spinlock_t lock;
#ifdef CONFIG_PM_SLEEP
struct list_head entry;
struct completion completion;
unsigned long wakeup_count;
struct wakeup_source *wakeup;
#endif
#ifdef CONFIG_PM_RUNTIME
struct timer_list suspend_timer;
unsigned long timer_expires;
struct work_struct work;
wait_queue_head_t wait_queue;
spinlock_t lock;
atomic_t usage_count;
atomic_t child_count;
unsigned int disable_depth:3;
@ -559,11 +560,6 @@ extern void __suspend_report_result(const char *function, void *fn, int ret);
} while (0)
extern void device_pm_wait_for_dev(struct device *sub, struct device *dev);
/* drivers/base/power/wakeup.c */
extern void pm_wakeup_event(struct device *dev, unsigned int msec);
extern void pm_stay_awake(struct device *dev);
extern void pm_relax(void);
#else /* !CONFIG_PM_SLEEP */
#define device_pm_lock() do {} while (0)
@ -577,10 +573,6 @@ static inline int dpm_suspend_start(pm_message_t state)
#define suspend_report_result(fn, ret) do {} while (0)
static inline void device_pm_wait_for_dev(struct device *a, struct device *b) {}
static inline void pm_wakeup_event(struct device *dev, unsigned int msec) {}
static inline void pm_stay_awake(struct device *dev) {}
static inline void pm_relax(void) {}
#endif /* !CONFIG_PM_SLEEP */
/* How to reorder dpm_list after device_move() */

View file

@ -2,6 +2,7 @@
* pm_wakeup.h - Power management wakeup interface
*
* Copyright (C) 2008 Alan Stern
* Copyright (C) 2010 Rafael J. Wysocki, Novell Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@ -27,18 +28,39 @@
#include <linux/types.h>
#ifdef CONFIG_PM
/* Changes to device_may_wakeup take effect on the next pm state change.
/**
* struct wakeup_source - Representation of wakeup sources
*
* By default, most devices should leave wakeup disabled. The exceptions
* are devices that everyone expects to be wakeup sources: keyboards,
* power buttons, possibly network interfaces, etc.
* @total_time: Total time this wakeup source has been active.
* @max_time: Maximum time this wakeup source has been continuously active.
* @last_time: Monotonic clock when the wakeup source's was activated last time.
* @event_count: Number of signaled wakeup events.
* @active_count: Number of times the wakeup sorce was activated.
* @relax_count: Number of times the wakeup sorce was deactivated.
* @hit_count: Number of times the wakeup sorce might abort system suspend.
* @active: Status of the wakeup source.
*/
struct wakeup_source {
char *name;
struct list_head entry;
spinlock_t lock;
struct timer_list timer;
unsigned long timer_expires;
ktime_t total_time;
ktime_t max_time;
ktime_t last_time;
unsigned long event_count;
unsigned long active_count;
unsigned long relax_count;
unsigned long hit_count;
unsigned int active:1;
};
#ifdef CONFIG_PM_SLEEP
/*
* Changes to device_may_wakeup take effect on the next pm state change.
*/
static inline void device_init_wakeup(struct device *dev, bool val)
{
dev->power.can_wakeup = dev->power.should_wakeup = val;
}
static inline void device_set_wakeup_capable(struct device *dev, bool capable)
{
@ -50,23 +72,32 @@ static inline bool device_can_wakeup(struct device *dev)
return dev->power.can_wakeup;
}
static inline void device_set_wakeup_enable(struct device *dev, bool enable)
{
dev->power.should_wakeup = enable;
}
static inline bool device_may_wakeup(struct device *dev)
{
return dev->power.can_wakeup && dev->power.should_wakeup;
return dev->power.can_wakeup && !!dev->power.wakeup;
}
#else /* !CONFIG_PM */
/* drivers/base/power/wakeup.c */
extern struct wakeup_source *wakeup_source_create(const char *name);
extern void wakeup_source_destroy(struct wakeup_source *ws);
extern void wakeup_source_add(struct wakeup_source *ws);
extern void wakeup_source_remove(struct wakeup_source *ws);
extern struct wakeup_source *wakeup_source_register(const char *name);
extern void wakeup_source_unregister(struct wakeup_source *ws);
extern int device_wakeup_enable(struct device *dev);
extern int device_wakeup_disable(struct device *dev);
extern int device_init_wakeup(struct device *dev, bool val);
extern int device_set_wakeup_enable(struct device *dev, bool enable);
extern void __pm_stay_awake(struct wakeup_source *ws);
extern void pm_stay_awake(struct device *dev);
extern void __pm_relax(struct wakeup_source *ws);
extern void pm_relax(struct device *dev);
extern void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec);
extern void pm_wakeup_event(struct device *dev, unsigned int msec);
/* For some reason the following routines work even without CONFIG_PM */
static inline void device_init_wakeup(struct device *dev, bool val)
{
dev->power.can_wakeup = val;
}
#else /* !CONFIG_PM_SLEEP */
static inline void device_set_wakeup_capable(struct device *dev, bool capable)
{
@ -78,15 +109,63 @@ static inline bool device_can_wakeup(struct device *dev)
return dev->power.can_wakeup;
}
static inline void device_set_wakeup_enable(struct device *dev, bool enable)
{
}
static inline bool device_may_wakeup(struct device *dev)
{
return false;
}
#endif /* !CONFIG_PM */
static inline struct wakeup_source *wakeup_source_create(const char *name)
{
return NULL;
}
static inline void wakeup_source_destroy(struct wakeup_source *ws) {}
static inline void wakeup_source_add(struct wakeup_source *ws) {}
static inline void wakeup_source_remove(struct wakeup_source *ws) {}
static inline struct wakeup_source *wakeup_source_register(const char *name)
{
return NULL;
}
static inline void wakeup_source_unregister(struct wakeup_source *ws) {}
static inline int device_wakeup_enable(struct device *dev)
{
return -EINVAL;
}
static inline int device_wakeup_disable(struct device *dev)
{
return 0;
}
static inline int device_init_wakeup(struct device *dev, bool val)
{
dev->power.can_wakeup = val;
return val ? -EINVAL : 0;
}
static inline int device_set_wakeup_enable(struct device *dev, bool enable)
{
return -EINVAL;
}
static inline void __pm_stay_awake(struct wakeup_source *ws) {}
static inline void pm_stay_awake(struct device *dev) {}
static inline void __pm_relax(struct wakeup_source *ws) {}
static inline void pm_relax(struct device *dev) {}
static inline void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec) {}
static inline void pm_wakeup_event(struct device *dev, unsigned int msec) {}
#endif /* !CONFIG_PM_SLEEP */
#endif /* _LINUX_PM_WAKEUP_H */

View file

@ -293,8 +293,8 @@ extern int unregister_pm_notifier(struct notifier_block *nb);
extern bool events_check_enabled;
extern bool pm_check_wakeup_events(void);
extern bool pm_get_wakeup_count(unsigned long *count);
extern bool pm_save_wakeup_count(unsigned long count);
extern bool pm_get_wakeup_count(unsigned int *count);
extern bool pm_save_wakeup_count(unsigned int count);
#else /* !CONFIG_PM_SLEEP */
static inline int register_pm_notifier(struct notifier_block *nb)

View file

@ -237,18 +237,18 @@ static ssize_t wakeup_count_show(struct kobject *kobj,
struct kobj_attribute *attr,
char *buf)
{
unsigned long val;
unsigned int val;
return pm_get_wakeup_count(&val) ? sprintf(buf, "%lu\n", val) : -EINTR;
return pm_get_wakeup_count(&val) ? sprintf(buf, "%u\n", val) : -EINTR;
}
static ssize_t wakeup_count_store(struct kobject *kobj,
struct kobj_attribute *attr,
const char *buf, size_t n)
{
unsigned long val;
unsigned int val;
if (sscanf(buf, "%lu", &val) == 1) {
if (sscanf(buf, "%u", &val) == 1) {
if (pm_save_wakeup_count(val))
return n;
}