tree 5c7748849e797445e502ab6dea03bd6c36ad781e
parent 0ad45b33c58dca60dec7e1fb44766753bc4a7a38
author Masami Hiramatsu <mhiramat@kernel.org> 1474644916 +0900
committer Arnaldo Carvalho de Melo <acme@redhat.com> 1475158628 -0300

perf probe: Fix to cut off incompatible chars from group name

Cut off the characters which can not use for group name of uprobes
when making it based on executable filename.

For example, if the exec name is libstdc++.so, without this fix
perf probe generates "probe_libstdc++" as the group name, but
it is failed to set because '+' can not be used for group name.

With this fix perf accepts only alphabet, number or '_' for group
name, thus perf generates "probe_libstdc" as the group name.

E.g. with this fix, you can see the event name has no "+".
  ----
  $ ./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
  ----

Committer note:

Before this fix:

  # perf probe -x /usr/lib64/libstdc++.so.6 is_open
  Failed to write event: Invalid argument
    Error: Failed to add events.
  #

After the fix:

  # perf probe -x /usr/lib64/libstdc++.so.6 is_open
  Added new events:
    probe_libstdc:is_open (on is_open in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_1 (on is_open in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_2 (on is_open in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_3 (on is_open in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_4 (on is_open in /usr/lib64/libstdc++.so.6.0.22)

  You can now use it in all perf tools, such as:

	  perf record -e probe_libstdc:is_open_4 -aR sleep 1

  # perf probe -l probe_libstdc:*
    probe_libstdc:is_open (on is_open@libstdc++-v3/include/fstream in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_1 (on is_open@libstdc++-v3/include/fstream in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_2 (on is_open@libstdc++-v3/include/fstream in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_3 (on is_open@src/c++98/basic_file.cc in /usr/lib64/libstdc++.so.6.0.22)
    probe_libstdc:is_open_4 (on stdio_filebuf:5@include/ext/stdio_filebuf.h in /usr/lib64/libstdc++.so.6.0.22)
  #

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/147464491667.29804.9553638175441827970.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>