USB: remove "locktree" routine from the hub driver

This patch (as892) removes the "locktree" routine from the hub driver.
It currently is used in only one place, by a single kernel thread;
hence it isn't doing any good.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 7020230..9464eb5 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -982,49 +982,6 @@ hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 }
 
 
-/* grab device/port lock, returning index of that port (zero based).
- * protects the upstream link used by this device from concurrent
- * tree operations like suspend, resume, reset, and disconnect, which
- * apply to everything downstream of a given port.
- */
-static int locktree(struct usb_device *udev)
-{
-       int                     t;
-       struct usb_device       *hdev;
-
-       if (!udev)
-               return -ENODEV;
-
-       /* root hub is always the first lock in the series */
-       hdev = udev->parent;
-       if (!hdev) {
-               usb_lock_device(udev);
-               return 0;
-       }
-
-       /* on the path from root to us, lock everything from
-        * top down, dropping parent locks when not needed
-        */
-       t = locktree(hdev);
-       if (t < 0)
-               return t;
-
-       /* everything is fail-fast once disconnect
-        * processing starts
-        */
-       if (udev->state == USB_STATE_NOTATTACHED) {
-               usb_unlock_device(hdev);
-               return -ENODEV;
-       }
-
-       /* when everyone grabs locks top->bottom,
-        * non-overlapping work may be concurrent
-        */
-       usb_lock_device(udev);
-       usb_unlock_device(hdev);
-       return udev->portnum;
-}
-
 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 {
        int i;
@@ -2594,10 +2551,7 @@ static void hub_events(void)
 
                /* Lock the device, then check to see if we were
                 * disconnected while waiting for the lock to succeed. */
-               if (locktree(hdev) < 0) {
-                       usb_put_intf(intf);
-                       continue;
-               }
+               usb_lock_device(hdev);
                if (hub != usb_get_intfdata(intf))
                        goto loop;