Re: [PATCH 0/1] tools: perf: Expose sample ID / stream ID to python scripts

From: Adrian Hunter
Date: Tue Jan 23 2024 - 06:32:43 EST


On 23/01/24 12:31, Ben Gainey wrote:
> This patch modifies the perf python scripting engine so that the ID and
> STREAM_ID are exposed as part of the sample so that they may be
> correlated to the corresponding throttle/unthrottle event (for example).
>
> NB: For scripts where perf_db_export_mode = True, this may be a breaking
> change depending on how the script is constructed. Each field is passed
> to `sample_table` as an argument so any script that is written as:
>
> def sample_table(db_id, evsel_id, machine_id, ..., cyc_cnt, flags)
>
> will now fail due to the changed number of arguments with:
>
> TypeError: sample_table() takes 25 positional arguments but 27 were given
>
> Scripts that use:
>
> def sample_table(*args)
>
> or some variation thereof will not be affected.

That is documented in tools/perf/Documentation/db-export.txt. It was
anticipated that more arguments could be added, so that should be OK.

>
> When `perf_db_export_mode = False`, the script should be unaffected as
> all the arguments are inserted into a dictionary.
>
> The export-to-xxx.py scripts use the (..., *x) form so are not affected.
>
>
> Ben Gainey (1):
> tools: perf: Expose sample ID / stream ID to python scripts
>
> tools/perf/Documentation/perf-script-python.txt | 4 ++--
> tools/perf/util/scripting-engines/trace-event-python.c | 8 +++++++-
> 2 files changed, 9 insertions(+), 3 deletions(-)
>