Userspace can use wakeup_sources debugfs node to plot history of suspend
blocking wakeup sources over device's boot cycle. This information can
then be used (1) for power-specific bug reporting and (2) towards
attributing battery consumption to specific processes over a period of
time.
However, debugfs doesn't have stable ABI. For this reason, create a
'struct device' to expose wakeup sources statistics in sysfs under
/sys/class/wakeup/ws<ID>/*.
Co-developed-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Co-developed-by: Stephen Boyd <swb...@chromium.org>
Signed-off-by: Stephen Boyd <swb...@chromium.org>
Signed-off-by: Tri Vo <tr...@android.com>
Tested-by: Tri Vo <tr...@android.com>
Tested-by: Kalesh Singh <kaleshsi...@google.com>
---
Documentation/ABI/testing/sysfs-class-wakeup | 76 +++++++++
drivers/acpi/device_pm.c | 3 +-
drivers/base/power/Makefile | 2 +-
drivers/base/power/wakeup.c | 18 +-
drivers/base/power/wakeup_stats.c | 171 +++++++++++++++++++
fs/eventpoll.c | 4 +-
include/linux/pm_wakeup.h | 15 +-
kernel/power/autosleep.c | 2 +-
kernel/power/wakelock.c | 10 ++
kernel/time/alarmtimer.c | 2 +-
10 files changed, 291 insertions(+), 12 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-class-wakeup
create mode 100644 drivers/base/power/wakeup_stats.c
v2:
- Updated Documentation/ABI/, as per Greg.
- Removed locks in attribute functions, as per Greg.
- Lifetimes of struct wakelock and struck wakeup_source are now different due to
the latter embedding a refcounted kobject. Changed it so that struct wakelock
only has a pointer to struct wakeup_source, instead of embedding it.
- Added CONFIG_PM_SLEEP_STATS that enables/disables wakeup source statistics in
sysfs.
v3:
Changes by Greg:
- Reworked code to use 'struct device' instead of raw kobjects.
- Updated documentation file.
- Only link wakeup_stats.o when CONFIG_PM_SLEEP_STATS is enabled.
Changes by Tri:
- Reverted changes to kernel/power/wakelock.c. 'struct device' hides kobject
operations. So no need to handle lifetimes in wakelock.c
v4:
- Added 'Co-developed-by:' and 'Tested-by:' fields to commit message.
- Moved new documentation to a separate file
Documentation/ABI/testing/sysfs-class-wakeup, as per Greg.
- Fixed copyright header in drivers/base/power/wakeup_stats.c, as per Greg.
v5:
- Removed CONFIG_PM_SLEEP_STATS
- Used PTR_ERR_OR_ZERO instead of if(IS_ERR(...)) + PTR_ERR, reported by
kbuild test robot <l...@intel.com>
- Stephen reported that a call to device_init_wakeup() and writing 'enabled' to
that device's power/wakeup file results in multiple wakeup source being
allocated for that device. Changed device_wakeup_enable() to check if device
wakeup was previously enabled.
Changes by Stephen:
- Changed stats location from /sys/class/wakeup/<name>/* to
/sys/class/wakeup/wakeup<ID>/*, where ID is an IDA-allocated integer. This
avoids name collisions in /sys/class/wakeup/ directory.
- Added a "name" attribute to wakeup sources, and updated documentation.
- Device registering the wakeup source is now the parent of the wakeup source.
Updated wakeup_source_register()'s signature and its callers accordingly.
v6:
- Changed stats location to /sys/class/wakeup/ws<ID>/*
- Replaced ida_simple_get()/ida_simple_remove() with ida_alloc()/ida_free() as
the former is deprecated.
- Reverted changes to device_init_wakeup(). Rafael is preparing a patch to deal
with extra wakeup source allocation in a separate patch.
diff --git a/Documentation/ABI/testing/sysfs-class-wakeup
b/Documentation/ABI/testing/sysfs-class-wakeup
new file mode 100644
index 000000000000..754aab8b6dcd
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-wakeup
@@ -0,0 +1,76 @@
+What: /sys/class/wakeup/
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ The /sys/class/wakeup/ directory contains pointers to all
+ wakeup sources in the kernel at that moment in time.
+
+What: /sys/class/wakeup/.../name
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ This file contains the name of the wakeup source.
+
+What: /sys/class/wakeup/.../active_count
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ This file contains the number of times the wakeup source was
+ activated.
+
+What: /sys/class/wakeup/.../event_count
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ This file contains the number of signaled wakeup events
+ associated with the wakeup source.
+
+What: /sys/class/wakeup/.../wakeup_count
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ This file contains the number of times the wakeup source might
+ abort suspend.
+
+What: /sys/class/wakeup/.../expire_count
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ This file contains the number of times the wakeup source's
+ timeout has expired.
+
+What: /sys/class/wakeup/.../active_time_ms
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ This file contains the amount of time the wakeup source has
+ been continuously active, in milliseconds. If the wakeup
+ source is not active, this file contains '0'.
+
+What: /sys/class/wakeup/.../total_time_ms
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ This file contains the total amount of time this wakeup source
+ has been active, in milliseconds.
+
+What: /sys/class/wakeup/.../max_time_ms
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ This file contains the maximum amount of time this wakeup
+ source has been continuously active, in milliseconds.
+
+What: /sys/class/wakeup/.../last_change_ms
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ This file contains the monotonic clock time when the wakeup
+ source was touched last time, in milliseconds.
+
+What: /sys/class/wakeup/.../prevent_suspend_time_ms
+Date: June 2019
+Contact: Tri Vo <tr...@android.com>
+Description:
+ The file contains the total amount of time this wakeup source
+ has been preventing autosleep, in milliseconds.
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index 28cffaaf9d82..91634e2dba8a 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -495,7 +495,8 @@ acpi_status acpi_add_pm_notifier(struct acpi_device *adev,
struct device *dev,
goto out;
mutex_lock(&acpi_pm_notifier_lock);
- adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
+ adev->wakeup.ws = wakeup_source_register(&adev->dev,
+ dev_name(&adev->dev));
adev->wakeup.context.dev = dev;
adev->wakeup.context.func = func;
adev->wakeup.flags.notifier_present = true;
diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile
index e1bb691cf8f1..ec5bb190b9d0 100644
--- a/drivers/base/power/Makefile
+++ b/drivers/base/power/Makefile
@@ -1,6 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_PM) += sysfs.o generic_ops.o common.o qos.o runtime.o
wakeirq.o
-obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o
+obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o wakeup_stats.o
obj-$(CONFIG_PM_TRACE_RTC) += trace.o
obj-$(CONFIG_PM_GENERIC_DOMAINS) += domain.o domain_governor.o
obj-$(CONFIG_HAVE_CLK) += clock_ops.o
diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index ee31d4f8d856..79668b45eae6 100644
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -200,16 +200,25 @@ EXPORT_SYMBOL_GPL(wakeup_source_remove);
/**
* wakeup_source_register - Create wakeup source and add it to the list.
+ * @dev: Device this wakeup source is associated with (or NULL if virtual).
* @name: Name of the wakeup source to register.
*/
-struct wakeup_source *wakeup_source_register(const char *name)
+struct wakeup_source *wakeup_source_register(struct device *dev,
+ const char *name)
{
struct wakeup_source *ws;
+ int ret;
ws = wakeup_source_create(name);
- if (ws)
+ if (ws) {
+ ret = wakeup_source_sysfs_add(dev, ws);
+ if (ret) {
+ kfree_const(ws->name);
+ kfree(ws);
+ return NULL;
+ }
wakeup_source_add(ws);
-
+ }
return ws;
}
EXPORT_SYMBOL_GPL(wakeup_source_register);
@@ -222,6 +231,7 @@ void wakeup_source_unregister(struct wakeup_source *ws)
{
if (ws) {
wakeup_source_remove(ws);
+ wakeup_source_sysfs_remove(ws);
wakeup_source_destroy(ws);
}
}
@@ -265,7 +275,7 @@ int device_wakeup_enable(struct device *dev)
if (pm_suspend_target_state != PM_SUSPEND_ON)
dev_dbg(dev, "Suspicious %s() during system transition!\n",
__func__);
- ws = wakeup_source_register(dev_name(dev));
+ ws = wakeup_source_register(dev, dev_name(dev));
if (!ws)
return -ENOMEM;
diff --git a/drivers/base/power/wakeup_stats.c
b/drivers/base/power/wakeup_stats.c
new file mode 100644
index 000000000000..a26f019faca9
--- /dev/null
+++ b/drivers/base/power/wakeup_stats.c
@@ -0,0 +1,171 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Wakeup statistics in sysfs
+ *
+ * Copyright (c) 2019 Linux Foundation
+ * Copyright (c) 2019 Greg Kroah-Hartman <gre...@linuxfoundation.org>
+ * Copyright (c) 2019 Google Inc.
+ */
+
+#include <linux/idr.h>
+#include <linux/kdev_t.h>
+#include <linux/slab.h>
+
+#include "power.h"
+
+static struct class *wakeup_class;
+
+#define wakeup_attr(_name) \
+static ssize_t _name##_show(struct device *dev,
\
+ struct device_attribute *attr, char *buf) \
+{ \
+ struct wakeup_source *ws = dev_get_drvdata(dev); \
+ \
+ return sprintf(buf, "%lu\n", ws->_name); \
+} \
+static DEVICE_ATTR_RO(_name)
+
+wakeup_attr(active_count);
+wakeup_attr(event_count);
+wakeup_attr(wakeup_count);
+wakeup_attr(expire_count);
+
+static ssize_t active_time_ms_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct wakeup_source *ws = dev_get_drvdata(dev);
+ ktime_t active_time =
+ ws->active ? ktime_sub(ktime_get(), ws->last_time) : 0;
+
+ return sprintf(buf, "%lld\n", ktime_to_ms(active_time));
+}
+static DEVICE_ATTR_RO(active_time_ms);
+
+static ssize_t total_time_ms_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct wakeup_source *ws = dev_get_drvdata(dev);
+ ktime_t active_time;
+ ktime_t total_time = ws->total_time;
+
+ if (ws->active) {
+ active_time = ktime_sub(ktime_get(), ws->last_time);
+ total_time = ktime_add(total_time, active_time);
+ }
+ return sprintf(buf, "%lld\n", ktime_to_ms(total_time));
+}
+static DEVICE_ATTR_RO(total_time_ms);
+
+static ssize_t max_time_ms_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct wakeup_source *ws = dev_get_drvdata(dev);
+ ktime_t active_time;
+ ktime_t max_time = ws->max_time;
+
+ if (ws->active) {
+ active_time = ktime_sub(ktime_get(), ws->last_time);
+ if (active_time > max_time)
+ max_time = active_time;
+ }
+ return sprintf(buf, "%lld\n", ktime_to_ms(max_time));
+}
+static DEVICE_ATTR_RO(max_time_ms);
+
+static ssize_t last_change_ms_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct wakeup_source *ws = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%lld\n", ktime_to_ms(ws->last_time));
+}
+static DEVICE_ATTR_RO(last_change_ms);
+
+static ssize_t name_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct wakeup_source *ws = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%s\n", ws->name);
+}
+static DEVICE_ATTR_RO(name);
+
+static ssize_t prevent_suspend_time_ms_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct wakeup_source *ws = dev_get_drvdata(dev);
+ ktime_t prevent_sleep_time = ws->prevent_sleep_time;
+
+ if (ws->active && ws->autosleep_enabled) {
+ prevent_sleep_time = ktime_add(prevent_sleep_time,
+ ktime_sub(ktime_get(), ws->start_prevent_time));
+ }
+ return sprintf(buf, "%lld\n", ktime_to_ms(prevent_sleep_time));
+}
+static DEVICE_ATTR_RO(prevent_suspend_time_ms);
+
+static struct attribute *wakeup_source_attrs[] = {
+ &dev_attr_name.attr,
+ &dev_attr_active_count.attr,
+ &dev_attr_event_count.attr,
+ &dev_attr_wakeup_count.attr,
+ &dev_attr_expire_count.attr,
+ &dev_attr_active_time_ms.attr,
+ &dev_attr_total_time_ms.attr,
+ &dev_attr_max_time_ms.attr,
+ &dev_attr_last_change_ms.attr,
+ &dev_attr_prevent_suspend_time_ms.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(wakeup_source);
+
+static DEFINE_IDA(wakeup_ida);
+
+/**
+ * wakeup_source_sysfs_add - Add wakeup_source attributes to sysfs.
+ * @parent: Device given wakeup source is associated with (or NULL if virtual).
+ * @ws: Wakeup source to be added in sysfs.
+ */
+int wakeup_source_sysfs_add(struct device *parent, struct wakeup_source *ws)
+{
+ struct device *dev;
+ int id;
+
+ id = ida_alloc(&wakeup_ida, GFP_KERNEL);
+ if (id < 0)
+ return id;
+ ws->id = id;
+
+ dev = device_create_with_groups(wakeup_class, parent, MKDEV(0, 0), ws,
+ wakeup_source_groups, "ws%d",
+ ws->id);
+ if (IS_ERR(dev)) {
+ ida_free(&wakeup_ida, ws->id);
+ return PTR_ERR(dev);
+ }
+
+ ws->dev = dev;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(wakeup_source_sysfs_add);
+
+/**
+ * wakeup_source_sysfs_remove - Remove wakeup_source attributes from sysfs.
+ * @ws: Wakeup source to be removed from sysfs.
+ */
+void wakeup_source_sysfs_remove(struct wakeup_source *ws)
+{
+ device_unregister(ws->dev);
+ ida_simple_remove(&wakeup_ida, ws->id);
+}
+EXPORT_SYMBOL_GPL(wakeup_source_sysfs_remove);
+
+static int __init wakeup_sources_sysfs_init(void)
+{
+ wakeup_class = class_create(THIS_MODULE, "wakeup");
+
+ return PTR_ERR_OR_ZERO(wakeup_class);
+}
+
+postcore_initcall(wakeup_sources_sysfs_init);
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index d7f1f5011fac..c4159bcc05d9 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1459,13 +1459,13 @@ static int ep_create_wakeup_source(struct epitem *epi)
struct wakeup_source *ws;
if (!epi->ep->ws) {
- epi->ep->ws = wakeup_source_register("eventpoll");
+ epi->ep->ws = wakeup_source_register(NULL, "eventpoll");
if (!epi->ep->ws)
return -ENOMEM;
}
name = epi->ffd.file->f_path.dentry->d_name.name;
- ws = wakeup_source_register(name);
+ ws = wakeup_source_register(NULL, name);
if (!ws)
return -ENOMEM;
diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h
index 91027602d137..f39f768389c8 100644
--- a/include/linux/pm_wakeup.h
+++ b/include/linux/pm_wakeup.h
@@ -21,6 +21,7 @@ struct wake_irq;
* struct wakeup_source - Representation of wakeup sources
*
* @name: Name of the wakeup source
+ * @id: Wakeup source id
* @entry: Wakeup source list entry
* @lock: Wakeup source lock
* @wakeirq: Optional device specific wakeirq
@@ -35,11 +36,13 @@ struct wake_irq;
* @relax_count: Number of times the wakeup source was deactivated.
* @expire_count: Number of times the wakeup source's timeout has expired.
* @wakeup_count: Number of times the wakeup source might abort suspend.
+ * @dev: Struct device for sysfs statistics about the wakeup source.
* @active: Status of the wakeup source.
* @autosleep_enabled: Autosleep is active, so update @prevent_sleep_time.
*/
struct wakeup_source {
const char *name;
+ int id;
struct list_head entry;
spinlock_t lock;
struct wake_irq *wakeirq;
@@ -55,6 +58,7 @@ struct wakeup_source {
unsigned long relax_count;
unsigned long expire_count;
unsigned long wakeup_count;
+ struct device *dev;
bool active:1;
bool autosleep_enabled:1;
};
@@ -86,7 +90,8 @@ 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 struct wakeup_source *wakeup_source_register(struct device *dev,
+ 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);
@@ -100,6 +105,11 @@ extern void pm_relax(struct device *dev);
extern void pm_wakeup_ws_event(struct wakeup_source *ws, unsigned int msec,
bool hard);
extern void pm_wakeup_dev_event(struct device *dev, unsigned int msec, bool
hard);
+/* drivers/base/power/wakeup_stats.c */
+extern int wakeup_source_sysfs_add(struct device *parent,
+ struct wakeup_source *ws);
+extern void wakeup_source_sysfs_remove(struct wakeup_source *ws);
+
#else /* !CONFIG_PM_SLEEP */
static inline void device_set_wakeup_capable(struct device *dev, bool capable)
@@ -126,7 +136,8 @@ 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)
+static inline struct wakeup_source *wakeup_source_register(struct device *dev,
+ const char *name)
{
return NULL;
}
diff --git a/kernel/power/autosleep.c b/kernel/power/autosleep.c
index 41e83a779e19..9af5a50d3489 100644
--- a/kernel/power/autosleep.c
+++ b/kernel/power/autosleep.c
@@ -116,7 +116,7 @@ int pm_autosleep_set_state(suspend_state_t state)
int __init pm_autosleep_init(void)
{
- autosleep_ws = wakeup_source_register("autosleep");
+ autosleep_ws = wakeup_source_register(NULL, "autosleep");
if (!autosleep_ws)
return -ENOMEM;
diff --git a/kernel/power/wakelock.c b/kernel/power/wakelock.c
index 4210152e56f0..826fcd97647a 100644
--- a/kernel/power/wakelock.c
+++ b/kernel/power/wakelock.c
@@ -122,6 +122,7 @@ static void __wakelocks_gc(struct work_struct *work)
if (!active) {
wakeup_source_remove(&wl->ws);
+ wakeup_source_sysfs_remove(&wl->ws);
rb_erase(&wl->node, &wakelocks_tree);
list_del(&wl->lru);
kfree(wl->name);
@@ -153,6 +154,7 @@ static struct wakelock *wakelock_lookup_add(const char
*name, size_t len,
struct rb_node **node = &wakelocks_tree.rb_node;
struct rb_node *parent = *node;
struct wakelock *wl;
+ int ret;
while (*node) {
int diff;
@@ -189,6 +191,14 @@ static struct wakelock *wakelock_lookup_add(const char
*name, size_t len,
}
wl->ws.name = wl->name;
wl->ws.last_time = ktime_get();
+
+ ret = wakeup_source_sysfs_add(NULL, &wl->ws);
+ if (ret) {
+ kfree(wl->name);
+ kfree(wl);
+ return ERR_PTR(ret);
+ }
+
wakeup_source_add(&wl->ws);
rb_link_node(&wl->node, parent, node);
rb_insert_color(&wl->node, &wakelocks_tree);
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 57518efc3810..93b382d9701c 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -97,7 +97,7 @@ static int alarmtimer_rtc_add_device(struct device *dev,
if (!device_may_wakeup(rtc->dev.parent))
return -1;
- __ws = wakeup_source_register("alarmtimer");
+ __ws = wakeup_source_register(dev, "alarmtimer");
spin_lock_irqsave(&rtcdev_lock, flags);
if (!rtcdev) {
--
2.22.0.709.g102302147b-goog
