[PATCH v4] usb: create usb_debug_root for gadget only

Greg Kroah-Hartman gregkh at linuxfoundation.org
Tue Jun 4 01:24:07 PDT 2019


On Tue, Jun 04, 2019 at 10:47:55AM +0300, Felipe Balbi wrote:
> 
> Hi,
> 
> Greg Kroah-Hartman <gregkh at linuxfoundation.org> 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



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