Commit 15123006 authored by Sarah Sharp's avatar Sarah Sharp Committed by Greg Kroah-Hartman
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USB: Export suspend statistics



This patch exports two statistics to userspace:
/sys/bus/usb/device/.../power/connected_duration
/sys/bus/usb/device/.../power/active_duration

connected_duration is the total time (in msec) that the device has
been connected.  active_duration is the total time the device has not
been suspended.  With these two statistics, tools like PowerTOP can
calculate the percentage time that a device is active, i.e. not
suspended or auto-suspended.

Users can also use the active_duration to check if a device is actually
autosuspended.  Currently, they can set power/level to auto and
power/autosuspend to a positive timeout, but there's no way to know from
userspace if a device was actually autosuspended without looking at the
dmesg output.  These statistics will be useful in creating an automated
userspace script to test autosuspend for USB devices.
Signed-off-by: default avatarSarah Sharp <sarah.a.sharp@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 228426ed
......@@ -1034,8 +1034,10 @@ static void recursively_mark_NOTATTACHED(struct usb_device *udev)
if (udev->children[i])
recursively_mark_NOTATTACHED(udev->children[i]);
}
if (udev->state == USB_STATE_SUSPENDED)
if (udev->state == USB_STATE_SUSPENDED) {
udev->discon_suspended = 1;
udev->active_duration -= jiffies;
}
udev->state = USB_STATE_NOTATTACHED;
}
......@@ -1084,6 +1086,12 @@ void usb_set_device_state(struct usb_device *udev,
else
device_init_wakeup(&udev->dev, 0);
}
if (udev->state == USB_STATE_SUSPENDED &&
new_state != USB_STATE_SUSPENDED)
udev->active_duration -= jiffies;
else if (new_state == USB_STATE_SUSPENDED &&
udev->state != USB_STATE_SUSPENDED)
udev->active_duration += jiffies;
udev->state = new_state;
} else
recursively_mark_NOTATTACHED(udev);
......
......@@ -248,6 +248,41 @@ static void remove_persist_attributes(struct device *dev)
#ifdef CONFIG_USB_SUSPEND
static ssize_t
show_connected_duration(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev = to_usb_device(dev);
return sprintf(buf, "%u\n",
jiffies_to_msecs(jiffies - udev->connect_time));
}
static DEVICE_ATTR(connected_duration, S_IRUGO, show_connected_duration, NULL);
/*
* If the device is resumed, the last time the device was suspended has
* been pre-subtracted from active_duration. We add the current time to
* get the duration that the device was actually active.
*
* If the device is suspended, the active_duration is up-to-date.
*/
static ssize_t
show_active_duration(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev = to_usb_device(dev);
int duration;
if (udev->state != USB_STATE_SUSPENDED)
duration = jiffies_to_msecs(jiffies + udev->active_duration);
else
duration = jiffies_to_msecs(udev->active_duration);
return sprintf(buf, "%u\n", duration);
}
static DEVICE_ATTR(active_duration, S_IRUGO, show_active_duration, NULL);
static ssize_t
show_autosuspend(struct device *dev, struct device_attribute *attr, char *buf)
{
......@@ -365,12 +400,26 @@ static int add_power_attributes(struct device *dev)
rc = sysfs_add_file_to_group(&dev->kobj,
&dev_attr_level.attr,
power_group);
if (rc == 0)
rc = sysfs_add_file_to_group(&dev->kobj,
&dev_attr_connected_duration.attr,
power_group);
if (rc == 0)
rc = sysfs_add_file_to_group(&dev->kobj,
&dev_attr_active_duration.attr,
power_group);
}
return rc;
}
static void remove_power_attributes(struct device *dev)
{
sysfs_remove_file_from_group(&dev->kobj,
&dev_attr_active_duration.attr,
power_group);
sysfs_remove_file_from_group(&dev->kobj,
&dev_attr_connected_duration.attr,
power_group);
sysfs_remove_file_from_group(&dev->kobj,
&dev_attr_level.attr,
power_group);
......
......@@ -339,6 +339,8 @@ usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
mutex_init(&dev->pm_mutex);
INIT_DELAYED_WORK(&dev->autosuspend, usb_autosuspend_work);
dev->autosuspend_delay = usb_autosuspend_delay * HZ;
dev->connect_time = jiffies;
dev->active_duration = -jiffies;
#endif
if (root_hub) /* Root hub always ok [and always wired] */
dev->authorized = 1;
......
......@@ -419,12 +419,15 @@ struct usb_device {
u32 quirks; /* quirks of the whole device */
atomic_t urbnum; /* number of URBs submitted for the whole device */
unsigned long active_duration; /* total time device is not suspended */
#ifdef CONFIG_PM
struct delayed_work autosuspend; /* for delayed autosuspends */
struct mutex pm_mutex; /* protects PM operations */
unsigned long last_busy; /* time of last use */
int autosuspend_delay; /* in jiffies */
unsigned long connect_time; /* time device was first connected */
unsigned auto_pm:1; /* autosuspend/resume in progress */
unsigned do_remote_wakeup:1; /* remote wakeup should be enabled */
......
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