Re: [PATCH perf/core 0/4] perf-probe fixes for C++

From: Jiri Olsa
Date: Sun Sep 25 2016 - 07:14:35 EST


On Sat, Sep 24, 2016 at 12:34:47AM +0900, Masami Hiramatsu wrote:
> Hi,
>
> Here is a series of patches for fixing several issues when
> probing on C++ binaries.
>
> - Ignore inlined function definition if it has no instance [1/4]
> - Skip (inlined/normal) functions which entry address is 0 [2/4]
> - Cut off the filename for group name if it includes characters
> which can not be used for C symbol name [3/4]
> - Search mangled symbol name from debuginfo [4/4]
>
> So, with this series, perf-probe can handle "mangled symbol" or
> "method name" as below;
> ----
> $ ./perf probe -x /usr/lib64/libstdc++.so.6 \
> -D _ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv
> p:probe_libstdc/_ZNKSt15basic_fstreamXXIwSt11char_traitsIwEE7is_openEv
> /usr/lib64/libstdc++.so.6.0.22:0x8ca60
>
> $ ./perf probe -x /usr/lib64/libstdc++.so.6 -D is_open
> p:probe_libstdc/is_open /usr/lib64/libstdc++.so.6.0.22:0x8ca80
> p:probe_libstdc/is_open_1 /usr/lib64/libstdc++.so.6.0.22:0x8ca70
> p:probe_libstdc/is_open_2 /usr/lib64/libstdc++.so.6.0.22:0x8ca60
> p:probe_libstdc/is_open_3 /usr/lib64/libstdc++.so.6.0.22:0xb0ad0
> p:probe_libstdc/is_open_4 /usr/lib64/libstdc++.so.6.0.22:0xecca9
> ----
>
> Jiri and Thomas, could you try this if you need it?

tried examples from changelogs and it works for me

Tested-by: Jiri Olsa <jolsa@xxxxxxxxxx>

thanks,
jirka

>
> TODO:
> - Support demangled method name(in short), like std::basic_fstream::is_open.
>
> Thank you,
>
> ---
>
> Masami Hiramatsu (4):
> perf-probe: Ignore the error of finding inline instance
> perf-probe: Skip if the function address is 0
> perf-probe: Fix to cut off incompatible chars from group name
> perf-probe: Match linkage name with mangled name
>
>
> tools/perf/util/dwarf-aux.c | 28 ++++++++++++++++++++++++++--
> tools/perf/util/dwarf-aux.h | 3 +++
> tools/perf/util/probe-event.c | 10 +++++++---
> tools/perf/util/probe-finder.c | 17 ++++++++++++++---
> 4 files changed, 50 insertions(+), 8 deletions(-)
>
> --
> Masami Hiramatsu