USB: Export URB statistics for powertop

powertop currently tracks interrupts generated by uhci, ehci, and ohci,
but it has no way of telling which USB device to blame USB bus activity on.
This patch exports the number of URBs that are submitted for a given device.
Cat the file 'urbnum' in /sys/bus/usb/devices/.../

Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 2c79aa6..3dd997d 100644 (file)
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1176,6 +1176,7 @@ int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
         */
        usb_get_urb(urb);
        atomic_inc(&urb->use_count);
+       atomic_inc(&urb->dev->urbnum);
        usbmon_urb_submit(&hcd->self, urb);
 
        /* NOTE requirements on root-hub callers (usbfs and the hub
@@ -1197,6 +1198,7 @@ int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
                urb->hcpriv = NULL;
                INIT_LIST_HEAD(&urb->urb_list);
                atomic_dec(&urb->use_count);
+               atomic_dec(&urb->dev->urbnum);
                if (urb->reject)
                        wake_up(&usb_kill_urb_queue);
                usb_put_urb(urb);

diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index e025902..b04afd0 100644 (file)
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -169,6 +169,16 @@ show_quirks(struct device *dev, struct device_attribute *attr, char *buf)
 }
 static DEVICE_ATTR(quirks, S_IRUGO, show_quirks, NULL);
 
+static ssize_t
+show_urbnum(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct usb_device *udev;
+
+       udev = to_usb_device(dev);
+       return sprintf(buf, "%d\n", atomic_read(&udev->urbnum));
+}
+static DEVICE_ATTR(urbnum, S_IRUGO, show_urbnum, NULL);
+
 
 #if defined(CONFIG_USB_PERSIST) || defined(CONFIG_USB_SUSPEND)
 static const char power_group[] = "power";
@@ -458,6 +468,7 @@ static struct attribute *dev_attrs[] = {
        &dev_attr_bConfigurationValue.attr,
        &dev_attr_bmAttributes.attr,
        &dev_attr_bMaxPower.attr,
+       &dev_attr_urbnum.attr,
        /* device attributes */
        &dev_attr_idVendor.attr,
        &dev_attr_idProduct.attr,

diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 8121edb..c99938d 100644 (file)
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -266,6 +266,7 @@ usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
        dev->dev.dma_mask = bus->controller->dma_mask;
        set_dev_node(&dev->dev, dev_to_node(bus->controller));
        dev->state = USB_STATE_ATTACHED;
+       atomic_set(&dev->urbnum, 0);
 
        INIT_LIST_HEAD(&dev->ep0.urb_list);
        dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;

diff --git a/include/linux/usb.h b/include/linux/usb.h
index e5b35e0..c10935f 100644 (file)
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -415,6 +415,7 @@ struct usb_device {
 
        int pm_usage_cnt;               /* usage counter for autosuspend */
        u32 quirks;                     /* quirks of the whole device */
+       atomic_t urbnum;                /* number of URBs submitted for the whole device */
 
 #ifdef CONFIG_PM
        struct delayed_work autosuspend; /* for delayed autosuspends */