perf pmu-events: Parallelize JSON and metric pre-computation in jevents.py

Browse source

Currently, jevents.py parses hundreds of JSON event and metric files
sequentially across all CPU architectures during Kbuild startup,
taking ~3.5 seconds of single-core execution time.

Refactor jevents.py to pre-populate its internal JSON AST cache in
parallel across all available CPU cores using
ProcessPoolExecutor. First gather all the paths with ftw and
collect_json, then spawn _parallel_read_json_events that starts
workers to just read the json events. Define the worker process
initializer _init_worker so that _arch_std_events is available under
spawn multiprocessing semantics.

This accelerates the JSON parsing phase by over 10x (from ~3.0s down
to ~290ms), reducing overall jevents.py execution time by 3.5x (from
~3.56s down to ~1.03s).

Tested-by: James Clark <james.clark@linaro.org>
Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

...

This commit is contained in:

Ian Rogers 2026-07-22 10:31:38 -07:00 • committed by Namhyung Kim

parent 1fa8d81be1

commit eaab2eb09d

1 changed files with 32 additions and 4 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

36

tools/perf/pmu-events/jevents.py

View file