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Message-ID: <6a55956e-4218-4e11-4d7b-841761430a42@arm.com>
Date:   Tue, 25 Apr 2023 12:03:28 +0100
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Subject: Re: [PATCH 2/7] perf tools: Add util function for overriding user set
 config values
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To:     Arnaldo Carvalho de Melo <acme@kernel.org>
Cc:     Adrian Hunter <adrian.hunter@intel.com>,
        linux-perf-users@vger.kernel.org, coresight@lists.linaro.org,
        shy828301@gmail.com, denik@google.com,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Mike Leach <mike.leach@linaro.org>,
        Leo Yan <leo.yan@linaro.org>,
        John Garry <john.g.garry@oracle.com>,
        Will Deacon <will@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Ian Rogers <irogers@google.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20230424134748.228137-1-james.clark@arm.com>
 <20230424134748.228137-3-james.clark@arm.com>
 <a7940a4a-fc62-17ca-834b-73628a54cc2a@intel.com>
 <ZEbAS2yx2fguW60w@kernel.org>
From:   James Clark <james.clark@arm.com>
In-Reply-To: <ZEbAS2yx2fguW60w@kernel.org>
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On 24/04/2023 18:45, Arnaldo Carvalho de Melo wrote:
> Em Mon, Apr 24, 2023 at 06:36:14PM +0300, Adrian Hunter escreveu:
>> On 24/04/23 16:47, James Clark wrote:
>>> There is some duplicated code to only override config values if they
>>> haven't already been set by the user so make a util function for this.
>>>
>>> Signed-off-by: James Clark <james.clark@arm.com>
>>
>> One minor comment, nevertheless:
>>
>> Acked-by: Adrian Hunter <adrian.hunter@intel.com>
> 
> I just moved to  evsel__set_config_if_unset() to util/pmu.c, next to
> some other evsel__ functions to not break the python.so binding, before
> I was getting:
> 
> [acme@quaco perf-tools-next]$ perf test -v python
> Couldn't bump rlimit(MEMLOCK), failures may take place when creating BPF maps, etc
>  19: 'import perf' in python                                         :
> --- start ---
> test child forked, pid 500086
> python usage test: "echo "import sys ; sys.path.append('/tmp/build/perf-tools-next/python'); import perf" | '/usr/bin/python3' "
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> ImportError: /tmp/build/perf-tools-next/python/perf.cpython-311-x86_64-linux-gnu.so: undefined symbol: perf_pmu__format_bits
> test child finished with -1
> ---- end ----
> 'import perf' in python: FAILED!
> [acme@quaco perf-tools-next]$
> 
> Please run 'perf test' and 'make -C tools/perf build-test' prior to
> sending pull requests,
> 
> Thanks, applied.
> 

Ah sorry! I ran it from an in source build and got the python import
error so I ignored that test. I see the new error if I run it from
tools/perf instead.

Interestingly with an out of source build it doesn't matter which cwd
you run the Python test from because $OUTPUT is an absolute path.
Normally I do an out of source build, but the Coresight tests don't
currently work with that. Which I will submit another fix for...

I don't know if it's worth getting rid of that edge by making sure
PYTHONPATH is always absolute even for in source builds or if it will
break something else like a make install? It's because of this line:

  -DPYTHONPATH="BUILD_STR($(OUTPUT)python)"

Will make sure that they all pass next time. I also sent a fix for the
build-test target on my platform.

> - Arnaldo
>