From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 2 Oct 2018 09:11:44 -0400 From: Steven Rostedt To: Jani Nikula Message-ID: <20181002091144.48f4e27f@gandalf.local.home> In-Reply-To: <87va6kkagg.fsf@intel.com> References: <20181001140402.0799a8f0@gandalf.local.home> <87va6kkagg.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Ksummit-discuss@lists.linuxfoundation.org Subject: Re: [Ksummit-discuss] [MAINTAINERS SUMMIT] Moving debugfs file systems into sysfs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 02 Oct 2018 11:40:47 +0300 Jani Nikula wrote: > On Mon, 01 Oct 2018, Steven Rostedt wrote: > > At Kernel Recipes, I talked with some people that have mature > > interfaces in the debugfs directory, but they can not access them on > > systems that have debugfs disabled. What would be the process to have > > these systems move out of debugfs? Should they create their own fs and > > be mounted in /sys/kernel, with a dedicated directory if the file system > > is enabled in the kernel (I had tracefs do that). > > > > Is this something we should discuss at Maintainers Summit? What is the > > process for mature debugfs directories? What's the justification to > > have them moved? Is there a better answer for this? > > I have a semi-related topic, hopefully not a complete thread > hijack... ;) > > I think module parameters should primarily be viewed as debug knobs > rather than ABI. Things should just work instead of requiring the user > to tweak module parameters. Of course, there's the whole spectrum > between ABI and "unsafe" module parameters, and parameters get added for > a plethora of reasons. > > However, all module parameters show up in sysfs instead of, say, > debugfs. Many debug options otherwise suitable for debugfs alone are > added as module parameters because of the convenience; with just a few > lines you can add the module parameter, get the sysfs, and have the > value be set before probe. There's nothing that compares, really. You mean to select some of the parameters to be debugfs knobs? (obviously we don't want all of them there). > > I suppose primarily I'd like to find a convenient way to move module > parameters to debugfs, so the other way round than Steven. Do others > struggle with this? Any ideas, thoughts, pointers? > I haven't had any issues, personally. -- Steve