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

Ingo Molnar
2006-09-16T08:29:57Z

* Roman Zippel <zippel@linux-m68k.org> wrote:

> > > > > This is simply not true, at the source level you can remove a
> > > > > static tracepoint as easily as a dynamic tracepoint, the
> > > > > effect of the missing trace information is the same either way.
> > > >
> > > > this is not true. I gave you one example already a few mails ago
> > > > [...]
> > >
> > > Function attributes also doesn't provide information local to the
> > > function.
> >
> > of course, but where does the above tracepoint i quoted use
> > information local to the function? A fair number of markups use
> > global functions because, surprise, alot of interesting activity
> > happens along global functions. So a healthy reduction in markups
> > can be achieved.
>
> But not completely, which is the whole point.

the point was what you said above, which i claimed and still claim to be
false: "at the source level you can remove a static tracepoint as easily
as a dynamic tracepoint, the effect of the missing trace information is
the same either way."

Your point is still incorrect. I gave you an example of how half of the
tracepoints could be removed under a dynamic scheme - while they couldnt
be removed under a static scheme. Hence that directly contradicts your
contention that "you can remove a static tracepoint as easily as a
dynamic tracepoint". Nothing more, nothing less. I just pointed out the
point in your thinking that i believe to be incorrect.

Reality is that you can remove a dynamic tracepoint much easier, due to
the fundamental flexibility of dynamic tracers. While with static
tracers, every tracepoint has to be _somewhere_ in the source code,
otherwise people like you will complain just like you did in this mail:
"you make life more difficult for static tracers for no reason".

You can concede my point or you can dispute that argument - but what you
did above was neither: you snipped all the quotations and you claimed a
totally new point. (which new point i never argued with: _of course_ i
never claimed that __trace function attributes can remove _all_ markups.
They can "only" remove half of them.)

Ingo