Re: condition variable cleanup and subtransactions

On Thu, Dec 21, 2017 at 6:46 AM, Thomas Munro
<thomas(dot)munro(at)enterprisedb(dot)com> wrote:
> On Fri, Dec 22, 2017 at 12:00 AM, Andres Freund <andres(at)anarazel(dot)de> wrote:
>> Oh. This seems to be a condition variable bug independent of PHJ. The
>> problem is that the DSM segment etc all get cleaned up in
>> *subtransaction* abort.
>>
>> Afaict it's a bug that AbortTransaction() does
>> ConditionVariableCancelSleep() but AbortSubTransaction() does not,
>> despite the latter releasing dsm segments via
>> ResourceOwnerRelease(RESOURCE_RELEASE_BEFORE_LOCKS).
>>
>> Adding that seems to fix the crash.
>>
>> This seems like something we need to backpatch.
>
> Agreed. That affects any user of condition variables inside DSM
> segments, including the released Parallel Index Scan and Parallel
> Bitmap Heap Scan code.

Fixed.

--
Robert Haas
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