Re: [PATCH v5 0/7] Avoid parsing tracepoint format just for id

[Namhyung Kim <namhyung@kernel.org>]

On Mon, Nov 18, 2024 at 02:53:38PM -0800, Ian Rogers wrote:
> The tracepoint format isn't needed to open an event, just the id for
> the config value. Refactor the use of evsel->tp_format to use an
> accessor that will lazily construct its value. In evsel__newtp_idx
> read the id so the config value can be set up/used.
> 
> This allows tracepoints to be used without libtraceevent in a number
> of tests. Other functionality is enabled without libtracevent, such as
> mapping a tracepoint id back to its name. There may be some
> performance benefit to code using tracepoints but not using the format
> information.
> 
> v5. Add perf env fixed found by Namhyung.
> v4. Rebase due to conflict with 9ac98662dbd3 ("perf: event: Remove deadcode")
> v3. Whitespace changes, Arnaldo.
> v2. Add additional error checking/handling in evsel__tp_format.
> 
> Ian Rogers (7):
>   perf env: Ensure failure broken topology file reads are always -1
>     encoded
>   tool api fs: Correctly encode errno for read/write open failures
>   perf trace-event: Constify print arguments
>   perf trace-event: Always build trace-event-info.c
>   perf evsel: Add/use accessor for tp_format
>   perf evsel: Allow evsel__newtp without libtraceevent
>   perf tests: Enable tests disabled due to tracepoint parsing

Reviewed-by: Namhyung Kim <namhyung@kernel.org>

Thanks,
Namhyung

> 
>  tools/lib/api/fs/fs.c                         |   6 +-
>  tools/perf/builtin-kmem.c                     |  12 +-
>  tools/perf/builtin-kwork.c                    |   3 +-
>  tools/perf/builtin-record.c                   |   2 -
>  tools/perf/builtin-script.c                   |   9 +-
>  tools/perf/builtin-trace.c                    |  79 +++++++++----
>  tools/perf/tests/Build                        |   6 +-
>  tools/perf/tests/builtin-test.c               |   2 -
>  tools/perf/tests/parse-events.c               |  25 +---
>  tools/perf/util/Build                         |   2 +-
>  tools/perf/util/data-convert-bt.c             |  10 +-
>  tools/perf/util/data-convert-json.c           |   8 +-
>  tools/perf/util/env.c                         |   9 +-
>  tools/perf/util/evsel.c                       | 110 +++++++++++++-----
>  tools/perf/util/evsel.h                       |   9 +-
>  tools/perf/util/evsel_fprintf.c               |   4 +-
>  tools/perf/util/parse-events.c                |  16 +--
>  tools/perf/util/perf_event_attr_fprintf.c     |   4 -
>  .../util/scripting-engines/trace-event-perl.c |   3 +-
>  .../scripting-engines/trace-event-python.c    |   3 +-
>  tools/perf/util/sort.c                        |  33 ++++--
>  tools/perf/util/trace-event-parse.c           |   2 +-
>  tools/perf/util/trace-event-scripting.c       |  10 +-
>  tools/perf/util/trace-event.h                 |   2 +-
>  24 files changed, 220 insertions(+), 149 deletions(-)
> 
> -- 
> 2.47.0.338.g60cca15819-goog
>