Re: [patch 0/4] perf_counter tools: support annotation of live kernel modules

Frederic Weisbecker
2009-07-03T08:54:11Z

On Fri, Jul 03, 2009 at 10:28:44AM +0200, Mike Galbraith wrote:
> On Fri, 2009-07-03 at 10:15 +0200, Ingo Molnar wrote:
> > * Mike Galbraith <efault@gmx.de> wrote:
> >
> > > > We need to calculate and cache the objdump annotation output
> > > > once, but after that it should be pretty fast as we just display
> > > > updated counts with the same lines over and over again. No
> > > > repeated objdump runs are needed.
> > >
> > > But active files follow symbols, which change on the fly.
> > >
> > > Besides, as mentioned previously, while displayed annotation was
> > > very cool, it took a lot of display space. For me, top with the
> > > ability to emit bic-disposable mini-reports would be my primary
> > > perf tools usage. I'd only use big brothers when I needed their
> > > power/detail.
> >
> > Ok, then how about putting some sort of interactivity into perf top?
> >
> > Up and down arrows would allow the walking of the histogram, and
> > hitting enter on a symbol would show the annotated function? It
> > would be way cool and more usable and more flexible than some
> > side-channel for mini-reports.
> >
> > PowerTop has a lot of good text interactivity code that might be
> > reused. (assuming it's under a kernel compatible license?)
> >
> > There's also the 'tig' tool - an interactive tool to walk Git
> > trees/commits. If it's under a compatible license that would be a
> > nice place to look for clues too - it has a very mature and
> > well-thought-out TUI in my opinion.
>
> Cool. I love free samples to bend/spindle/mutilate :)
>
> -Mike

The same interactivity could also apply to perf report, by dynamically
expanding callchains, linking to more details with annotate, etc...