Re: [RFC] perf tools: Filter out hidden symbols from labels

Namhyung Kim
2019-01-16T04:37:43Z

Hi,

On Tue, Jan 15, 2019 at 01:35:40PM -0300, Arnaldo Carvalho de Melo wrote:
> Em Tue, Jan 15, 2019 at 04:13:16PM +0000, Nick Clifton escreveu:
> > Hi Jiri,
> >
> > > When perf is built with annobin plugin (RHEL8 build) extra symbols
> > > are added to its binary:
> >
> > A bit of background for those wondering why annobin is creating
> > these symbols: Annobin is a plugin for gcc that records data
> > about how object file were built. It is specifically designed
> > to be able to cope with files that are built using multiple
> > different sets of optimization options. (Eg because of #pragma
> > directives or function specific optimization attributes). It
> > generates notes to cover each compiled region of code, and it
> > needs the symbols in order to be able to determine exactly which
> > areas in a linked binary were compiled with which options.
>
> Humm, it would be nice for perf annotate to show those options when one
> navigates the annotation, something like press some hotkey and see the
> optimization flags used. Is there any library that gets those
> annotations and put them in some linked list that we could use in
> tools/perf/?

If it's just an ELF note, we could parse it directly.

https://developers.redhat.com/blog/2018/02/20/annobin-storing-information-binaries/

Thanks,
Namhyung