Re: [PATCH] trace2 tests: guard pthread test with "PTHREAD"

From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Nov 25, 2022, 08:05 UTC
Message-ID: <221125.867czjo3ud.gmgdl@evledraar.gmail.com>
In-Reply-To: <xmqqilj3edtr.fsf@gitster.g>

On Fri, Nov 25 2022, Junio C Hamano wrote:

Show 18 quoted lines

> Ævar Arnfjörð Bjarmason  <avarab@gmail.com> writes:
>
>> Since 81071626ba1 (trace2: add global counter mechanism, 2022-10-24)
>> these tests have been failing when git is compiled with NO_PTHREADS=Y,
>> which is always the case e.g. if 'uname -s' is "NONSTOP_KERNEL".
>>
>> Reported-by: Randall S. Becker <randall.becker@nexbridge.ca>
>> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
>> ---
>>  t/t0211-trace2-perf.sh | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> Makes sense, to sweep the immediate breakage under prerequisite.
>
> But why would a global counter need threading?  I know that the
> counters can optionally report per-thread stats, but that is
> optional and it would still be useful if we can count events in a
> single-threaded program, no?

That was my thought as well, but these tests are specifically testing how it interacts with threading. The counter mechanism works in general without threading.

The test descriptions don't help, and should really say that they're to do with threading in particular, but I wanted to keep this as small as possible for rc[12] and the final, so I didn't fix that while-at-it.