Re: [Dle-develop] [PATCH -tip 0/8] perf-probe updates

[Ingo M. <mi...@el...>]

* Masami Hiramatsu <mhi...@re...> wrote:

> Hi Ingo,
> 
> I made several usability updates and added --del option
> for perf-probe. I think most of basic functions are implemented.
> I'm planning to support checking build-id next, because it
> can prevent users to use old vmlinux for debuginfo analysis.
> 
> Here are the todo list I have (most of them had been requested
> on LKML). I'd like to share this list with other developers
> who are interested in.
> 
> Short-term TODOs:
>   - Support checking kernel Build-ID
> 
> Long-term TODOs (future features):
>   - Support --line option to show which lines user can probe
>   - Support lazy string matching(glob?) for selecting probing
>     line
>   - Support sys_perf_counter_open (for non-root users)
>   - Support tracing static variables (non global)
>   - Support variable types from debuginfo (e.g. char, int, ...)
>   - Support fields of data structures (var->field)
>   - Support array (var[N])
>   - Support dynamic array-indexing (var[var2])
>   - Support string/dynamic arrays (*var, var[N..M])
>   - Support force type-casting ((type)var)
>   - Support the type of return value
> 
> Miscs:
>   - Support glob expression with --del option (like --del "*")
>   - Support event/group name specifying for new events
>   - Better support for probes on modules
>   - Symbol search by libelf/kallsyms
>   - Move onto libdw/libdwfl
>   - Storing file name/line number information in the
>     kernel for listing events
>   
> 
> Thank you,
> 
> ---
> 
> Masami Hiramatsu (8):
>       perf probe: Update perf-probe document
>       perf probe: Support --del option
>       trace-kprobe: Support delete probe syntax
>       perf probe: Support vmlinux on cwd by default
>       perf probe: Remove event suffix number _0
>       perf probe: Fix add-probe command syntax without --add option
>       perf probe: Change probe-added message more user-friendly
>       perf probe: Change event list format
> 
> 
>  kernel/trace/trace_kprobe.c             |   37 +++++++--
>  tools/perf/Documentation/perf-probe.txt |   21 ++++-
>  tools/perf/builtin-probe.c              |   76 ++++++++++++++++---
>  tools/perf/util/probe-event.c           |  122 ++++++++++++++++++++++++++++---
>  tools/perf/util/probe-event.h           |    1 
>  5 files changed, 217 insertions(+), 40 deletions(-)

Applied - thanks Masami!

These are very nice enhancements. I tried out the new features and they 
worked well, and the use of the tool is intuitive.

One hickup is that -d/--del does not appear to be working yet:

  # perf probe -l
  probe:schedule                           (on schedule)

  # perf probe -d probe:schedule
  Fatal: Failed to write event: Invalid argument

	Ingo