On Mon, 19 Sep 2016 11:54:02 +0200 Jiri Olsa <jo...@redhat.com> wrote:
> hi, > Thomas reported failure to add an uprobe on libstdc++.so.6 like: > > [jolsa@krava perf]$ sudo ./perf probe -x /usr/lib64/libstdc++.so.6 > 'std::ostream::flush' > Semantic error :There is non-digit char in line number. > Error: Command Parse Error. Ah, I should start adding mangling support on perf probe... > it does not work also if I use the mangled name like: > > [jolsa@krava perf]$ sudo ./perf probe -x /usr/lib64/libstdc++.so.6 > '_ZSt5flushIwSt11char_traitsIwEERSt13basic_ostreamIT_T0_ES6_' > Probe point '_ZSt5flushIwSt11char_traitsIwEERSt13basic_ostreamIT_T0_ES6_' not > found. > Error: Failed to add events. Hmm, could you try to find mangled symbol from the library as below? ./perf probe -x /usr/lib64/libstdc++.so.6 -F \* And also try to do adding probe with -v option again? In my case, I could find the mangled symbol, but failed to setup the probe... $ sudo ./perf probe -x /usr/lib/x86_64-linux-gnu/libstdc++.so.6 -v _ZSt5flushIwSt11char_traitsIwEERSt13basic_ostreamIT_T0_ES6_ probe-definition(0): _ZSt5flushIwSt11char_traitsIwEERSt13basic_ostreamIT_T0_ES6_ symbol:_ZSt5flushIwSt11char_traitsIwEERSt13basic_ostreamIT_T0_ES6_ file:(null) line:0 offset:0 return:0 lazy:(null) 0 arguments symbol:catch file:(null) line:0 offset:0 return:0 lazy:(null) symbol:throw file:(null) line:0 offset:0 return:0 lazy:(null) symbol:rethrow file:(null) line:0 offset:0 return:0 lazy:(null) Could not open debuginfo. Try to use symbols. Opening /sys/kernel/debug/tracing//uprobe_events write=1 Writing event: p:probe_libstdc++/_ZSt5flushIwSt11char_traitsIwEERSt13basic_ostreamIT_T0_ES6_ /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21:0x1114c0 Failed to write event: Invalid argument Error: Failed to add events. Reason: Invalid argument (Code: -22) dmsg -k said; [143725.339609] Failed to allocate trace_uprobe.(-22) [143725.339612] Failed to parse address or file. It seems we need to fix trace_uprobe.c at least. Thank you! -- Masami Hiramatsu <mhira...@kernel.org>
