Re: [PATCH v4 3.0-rc2-tip 20/22] 20: perf: perf interface for uprobes

Srikar Dronamraju
2011-06-07T16:13:12Z

* Arnaldo Carvalho de Melo <acme@infradead.org> [2011-06-07 11:21:16]:

> Em Tue, Jun 07, 2011 at 07:08:53PM +0530, Ananth N Mavinakayanahalli escreveu:
> > On Tue, Jun 07, 2011 at 09:30:39AM -0400, Christoph Hellwig wrote:
> > > On Tue, Jun 07, 2011 at 06:32:16PM +0530, Srikar Dronamraju wrote:
> > > > Enhances perf probe to user space executables and libraries.
> > > > Provides very basic support for uprobes.
>
> > > Nice. Does this require full debug info for symbolic probes,
> > > or can it also work with simple symbolc information?
>
> > It works only with symbol information for now.
> > It doesn't (yet) know how to use debuginfo :-)
>
> 'perf probe' uses perf symbol library, so it really don't have to know
> from where symbol resolution information is obtained, only if it needs
> things that are _just_ on debuginfo, such as line information, etc.
>
> But then that is also already supported in 'perf probe'.
>
> Or is there something else in particular you're thinking?
>

What Ananth was saying was that perf probe for uprobes still has to take
advantage of tracing using line number; Also it is still restricted to
showing only register contents and we still have to add support for variables. I know that perf symbol library has support for that
just that we have to enable it for uprobes.

--
Thanks and Regards
Srikar