Re: [PATCH 2/3] perf trace: Update eval_flag() flags array tomatch interrupt.h

From: Ingo Molnar
Date: Sun Oct 11 2009 - 04:55:24 EST



* Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote:

> On Tue, Oct 06, 2009 at 05:19:00PM +0200, Frederic Weisbecker wrote:
> > Yeah. We may want to do that by including trace/events/irq.h
> > and then use the show_softirq_name() macro defined there.
> >
> > The rest of the header can be wrapped through no-op macros and
> > stub includes.
>
> No, not at all. Performance tracing tools really should not be
> dependent on the kernel source. This kind of creep is exactly what I
> feared from putting the perf source in the kernel tree.

And you were full of it back then and you are full of it now as well.

Of course tools/perf/ can be dependent on the kernel source, as long as
it's all exposed cleanly. Runtime exposure of information is better of
course in many cases, but there's a balance to be stricken.

We already have deep and good dependencies between kernel code and
tools/perf: for example we use the kernel's list.h and lib/rbtree.c in
perf and those facilities are God-sent over user-space crap that for
example Glist is.

I tend to agree that softirq names might make sense to expose runtime as
well, but that is totally independent of your _idiotic_ argument that
this issue somehow talks against perf being part of the kernel source.

Really, give up that argument already - or if not, please engage in an
open, honest exchange about it. These drip-drip attacks you are doing,
without actually having the balls to argue your technical position are
somewhat annoying.

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/