From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261904AbULKBkH (ORCPT ); Fri, 10 Dec 2004 20:40:07 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261906AbULKBkH (ORCPT ); Fri, 10 Dec 2004 20:40:07 -0500 Received: from mail.kroah.org ([69.55.234.183]:29071 "EHLO perch.kroah.org") by vger.kernel.org with ESMTP id S261904AbULKBj7 (ORCPT ); Fri, 10 Dec 2004 20:39:59 -0500 Date: Fri, 10 Dec 2004 17:39:30 -0800 From: Greg KH To: David Brownell Cc: linux-usb-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [linux-usb-devel] [RFC PATCH] debugfs - yet another in-kernel file system Message-ID: <20041211013930.GB12846@kroah.com> References: <20041210005055.GA17822@kroah.com> <200412101729.01155.david-b@pacbell.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200412101729.01155.david-b@pacbell.net> User-Agent: Mutt/1.5.6i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 10, 2004 at 05:29:01PM -0800, David Brownell wrote: > On Thursday 09 December 2004 4:50 pm, Greg KH wrote: > > What if there was a in-kernel filesystem that was explicitly just for > > putting debugging stuff? ?Some place other than proc and sysfs, and that > > was easier than both of them to use. ?Yet it needed to also be able to > > handle complex stuff like seq file and raw file_ops if needed. > > The problem with sysfs here is: no seq_file support. > Otherwise it solves the basic "where to put the debug > files associated with "device X" or "driver Y" problems > in a good non-confusing way: there are directories > already set up for devices and for drivers. Yes, but that's a design decision for sysfs. no seq_file support is a feature, not a shortcoming :) > The problem with procfs here is that it doesn't have > such a naming solution: there's no automatic mapping > betwen a /proc/driver/...file and its device, or vice > versa. That issue is shared with debugfs. Agreed. > Couldn't debugfs just be a thin shim on top of sysfs, > adding seq_file support? Or on top of procfs, adding > device/driver naming domains, and maybe file-per-value > read/write support for drivers that want them? Ick. > What I'd really want out of a debug file API is to resolve > the naming issues, work with seq_file, and "softly and > silently vanish away". I think this patch has the last > two, but not the first one! I considered adding a kobject as a paramater to the debugfs interface. The file created would be equal to the path that the kobject has. Would that work for you? thanks, greg k-h