Re: [PATCH v4] usb: create usb_debug_root for gadget only

From: Greg Kroah-Hartman
Date: Tue Jun 04 2019 - 04:28:03 EST


On Tue, Jun 04, 2019 at 10:47:55AM +0300, Felipe Balbi wrote:
>
> Hi,
>
> Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> writes:
> >> +struct dentry *usb_debugfs_init(void)
> >> +{
> >> + if (!usb_debug_root)
> >> + usb_debug_root = debugfs_create_dir("usb", NULL);
> >> +
> >> + atomic_inc(&usb_debug_root_refcnt);
> >> +
> >> + return usb_debug_root;
> >> +}
> >> +EXPORT_SYMBOL_GPL(usb_debugfs_init);
> >> +
> >> +void usb_debugfs_cleanup(void)
> >> +{
> >> + if (atomic_dec_and_test(&usb_debug_root_refcnt)) {
> >> + debugfs_remove_recursive(usb_debug_root);
> >> + usb_debug_root = NULL;
> >> + }
> >> +}
> >> +EXPORT_SYMBOL_GPL(usb_debugfs_cleanup);
> >
> > Only remove the debugfs subdir if the usbcore module is removed. Create
> > the debugfs subdir when the usbcore module is loaded. No need for any
> > reference counting of any sort at all. No need to overthink this :)
>
> There is a slight need to overthink. He wants to use the same directory
> for gadget-only builds too :-)

Again, that's fine, this file will be loaded for those builds as well,
right? Otherwise, how would this code even be present? :)

thanks,

greg k-h