Re: [RFC 0/6] perf probe: Attempt to improve C++ probing

[Masami Hiramatsu <mhiramat@kernel.org>]

On Mon, 14 May 2018 12:19:34 +0800
Holger Freyther <automatic+kernel@freyther.de> wrote:

> From: Holger Hans Peter Freyther <holgar+kernel@google.com>
> 
> Currently perf probe -x app --funcs will list and demangle C++ functions
> but the other probe actions can't work with them. When asking probe to not
> demangle it will not list any of the application symbols creating the
> impression that there are no symbols at all.
> 
> Make --funcs --no-demangle list all C++ functions and modify the handling
> for listing code, variables and adding the uprobe work with the demangled
> C++ function name.
> 
> I tried to keep this as minimal as possible but having to keep the dso in
> the debuginfo and passing it everywhere to be able to demangle the linkage
> name isn't pretty (and for C++ demangling the struct dso is not of much
> use. Maybe having a static "empty" dso could avoid a lot of the changes).
> 
> Maybe the easiest first patch is to default to --no-demangle and change
> the DEFAULT_FUNC_FILTER to not include mangled C++ symbols. The remaining
> tooling would work then.
> 
> This has seen very little testing outside the following commands.
> 
> My test set includes:
> 
>  ./perf probe -x . -L "std::vector<int, std::allocator<int> >::at"
>  ./perf probe -x . -L "std::vector<int, std::allocator<int> >::at:2-3"
> 
>  ./perf probe -x . -V "std::vector<int, std::allocator<int> >::at"
>  ./perf probe -x . -V "std::vector<int, std::allocator<int> >::at:2"
>  ./perf probe -x . -V "std::vector<int, std::allocator<int> >::size%return"

OK, this series looks good to me :)

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
for this series.

Arnaldo, could you pull this series?

Thank you!


-- 
Masami Hiramatsu <mhiramat@kernel.org>