Re: [PATCH 00/05] Linux Kernel Markers - kernel 2.6.20

Mathieu Desnoyers
2007-02-15T22:30:40Z

* Andrew Morton (akpm@linux-foundation.org) wrote:
> On 15 Feb 2007 10:28:57 -0500
> fche@redhat.com (Frank Ch. Eigler) wrote:
>
> >
> > akpm wrote:
> >
> > > [...] And what can I do with these markers? And once I've done it,
> > > are there any userspace applications I can use to get the data out
> > > in human-usable form? [...]
> >
> > The LTTng user-space programs use it today. Systemtap used to support
> > the earlier marker prototype and will be rapidly ported over to this
> > new API upon acceptance.
> >
>
> That's good.
>
> It would be beneficial if some people from those projects could spare the
> cycles to carefully review and runtime test this code.
>
LTTng is using the marker infrastructure since last november. Me and my
users have been very happy with it.

> Also, I'm not 100% clear on where we ended up with the huge
> static-vs-dynamic flamewar. Did everyone end up happy? Is this patchset a
> reasonable compromise? Or do we need a rematch?

I think the final agreement was the need for some kind of code marking
system, which I tried to implement as best as I could. It gives very
good performances while tracing (advantage of static tracing), has a
very very minimal performance and binary size impact when disabled
(advantage of dynamic tracing) and it can be activated dynamically
(advantage of dynamic tracing).

Mathieu

--
Mathieu Desnoyers
Computer Engineering Ph.D. Candidate, École Polytechnique de Montréal
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68