Re: [RFC PATCH]debugfs:Fix terminology inconsistency of dir nameto mount debugfs filesystem.

From: Greg KH
Date: Tue May 26 2009 - 17:02:59 EST

On Tue, May 26, 2009 at 04:44:49PM -0400, Steven Rostedt wrote:
> On Tue, 26 May 2009, GeunSik Lim wrote:
> >
> >
> > Hi all,
> >
> > I want to hear your opinions about this proposal for consistency of
> > mount directory to mount debugfs filesystem that need by ftrace infrastructure.
> > Um... I appended "RFC" word in the subject because this mail is my proposal just.
> >
> >
> > commit 1766a83645706100b1829bb422f852ec757c6f4b
> > Author: GeunSik,Lim <leemgs1@xxxxxxxxx>
> > Date: Tue May 26 13:49:23 2009 +0900
> >
> > Fix terminology inconsistency of dir name to mount debugfs filesystem.
> >
> > Many developers use "/debug/" directory name to mount debugfs filesystem
> > for ftrace according to ./Documentation/tracers/ftrace.txt file.
> >
> > But, two directory names(ex:/debug/, /debugfs/) is existed in kernel source
> > like ftrace, DRM, Wireless, Network[sky2]files to mount debugfs filesystem.
> > I think that we don't have to select either "/debug/" directory name or
> > "/debugfs/" directory name for terminology consistency.
> >
> > debugfs means debug filesystem for debugging easy to use by greg kroah
> > hartman. "/debug/" name is suitable as directory name of debugfs for
> > tracing using ftrace like "/sys/" of sysfs(system filesystem).
> > -debugfs related reference:
> >
> > Fix inconsistency of directory name according to duplicated expression
> > to mount debugfs.
> >
> > Signed-off-by: GeunSik Lim <geunsik.lim@xxxxxxxxxxx>
> I'm guilty of using both /debug and /debugfs in comments. In practice, I
> only use /debug.
> But...
> The filesystem Nazi's out there will argue that the proper place to mount
> the debugfs filesystem is /sys/kernel/debug. I personally find that
> location annoying.


When I created debugfs, I was told that I had to pick a place to mount
it so that everyone could write scripts that "knew" where it would be.

So we picked /sys/kernel/debug/ and the code creates the mount point to
put it there. Now distros actually mount debugfs at that location.

So, now you don't like this? After it's become a standard? Ick.

Becides, /debug/ is pretty presumptious, it's as if debugging the kernel
is a system-wide thing :)

So please, don't use /debug/ use the standard, defined, and ACTUALLY
USED BY DISTROS TODAY mount point of /sys/kernel/debug/

If you want to create your own symlink from /debug/ to that location to
make it easier to type, feel free, but do not hard code any scripts to
use that location, or they are going to break.


greg k-h
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