From stern@rowland.harvard.edu Fri May 4 08:54:51 2007 Date: Fri, 4 May 2007 11:54:50 -0400 (EDT) From: Alan Stern To: Greg KH Subject: [PATCH 10/16] USB: remove "locktree" routine from the hub driver Message-ID: 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 Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 48 +----------------------------------------------- 1 file changed, 1 insertion(+), 47 deletions(-) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -982,49 +982,6 @@ hub_ioctl(struct usb_interface *intf, un } -/* 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; @@ -2582,10 +2539,7 @@ 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;