Received-SPF: pass (google.com: domain of linux-kernel+bounces-35199-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
Message-ID: <089e43c5-1e0e-4c6e-9b91-827b01012b23@intel.com>
Date: Tue, 23 Jan 2024 13:32:19 +0200
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH 0/1] tools: perf: Expose sample ID / stream ID to python
 scripts
Content-Language: en-US
To: Ben Gainey <ben.gainey@arm.com>, linux-perf-users@vger.kernel.org,
 linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Cc: peterz@infradead.org, mingo@redhat.com, acme@kernel.org,
 mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org,
 namhyung@kernel.org, irogers@google.com, will@kernel.org
References: <20240123103137.1890779-1-ben.gainey@arm.com>
From: Adrian Hunter <adrian.hunter@intel.com>
Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki,
 Business Identity Code: 0357606 - 4, Domiciled in Helsinki
In-Reply-To: <20240123103137.1890779-1-ben.gainey@arm.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit

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(-)
>