Re: [PATCH] x86: add the debugfs interface for the sysprof tool

From: John Levon
Date: Sun Feb 24 2008 - 11:34:19 EST


On Sun, Feb 24, 2008 at 08:10:02AM -0500, Theodore Tso wrote:

> > Firstly, the distributions should have set this up automatically. That
> > they don't is a distributor bug. The sheer madness of Linux not leaving
> > a vmlinux file in a stable known location is hardly something oprofile
> > can be blamed for.
>
> Wrong Answer. People who write userspace helpers *have* to do the
> work of the distro's. It's a bad, bad, bad, Bad, BAD idea to leave it
> up to the distributions. It means that some distributions won't get
> it right; other distributions will do it in different ways, making it
> harder for users to switch between distro's and making it harder for
> people to write distribution-neutral HOWTO's.

Hi Ted. I would have loved to have fixed it myself, or had one of the
other oprofile contributors do so. Unfortunately I have no control over
what the distributions do. For example:

https://bugzilla.redhat.com/show_bug.cgi?id=139767

> There are plenty of things that can be done, including using search
> paths to try to find vmlinuz; or maybe even proposing a new standard
> such as say for example /lib/modules/`uname -r`/vmlinux being a

At the time when I was trying to fix this, I wasn't aware of any way to
propose a new standard and get distributions to follow it - is there
some way now? Informally I discussed this problem several times with
many people without any resolution. As regards searching informal paths,
this is extremely risky - get the wrong vmlinux and we end up with
inaccurate results, which is worse than no results.

> The abdication of responsibility and the lack of trying to solve the
> usability issues is one of the things that really worries me about
> *all* of Linux's RAS tools. We can and should do better! And it's
> really embarassing that the RAS maintainers seem (I assume you are one
> of the oprofile maintainers), seem to be blaming this on the victims,
> the people who are complaining about using *your* tool. Yes, it's a

I'm not abdicating responsibility: I no longer maintain oprofile,
haven't for a long time, and the other contributors don't have any real
time to spend on it either. I'm well aware there are improvements to be
made: when I (and others) had time, this stuff was improving massively
with each release. When Soren et al had a need for a simple tool + GUI,
they should have helped out with this: it's simply good engineering to
not duplicate efforts. I didn't even get a /single/ email.

regards,
john
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