Re: [PATCH 0/11] LTTng-core (basic tracing infrastructure) 0.5.108

Ingo Molnar
2006-09-14T20:09:37Z

* Tim Bird <tim.bird@am.sony.com> wrote:

> > that's not true, and this is the important thing that i believe you
> > are missing. A dynamic tracepoint is _detached_ from the normal
> > source code and thus is zero maintainance overhead. You dont have to
> > maintain it during normal development - only if you need it. You
> > dont see the dynamic tracepoints in the source code.
>
> It's only zero maintenance overhead for you. Someone has to maintain
> it. The party line for years has been that in-tree maintenance is
> easier than out-of-tree maintenance.

There's a third option, and that's the one i'm advocating: adding the
tracepoint rules to the kernel, but in a _detached_ form from the actual
source code.

yes, someone has to maintain it, but that will be a detached effort, on
a low-frequency as-needed basis. It doesnt slow down or hinder
high-frequency fast prototyping work, it does not impact the source code
visually, and it does not make reading the code harder. Furthermore,
while a single broken LTT tracepoint prevents the kernel from building
at all, a single broken dynamic rule just wont be inserted into the
kernel. All the other rules are still very much intact.

Ingo