On Thu, 30 Jun 2022 12:08:19 GMT, Сергей Цыпанов <[email protected]> wrote:
>> If there are two threads calling `Executable.hasRealParameterData()` under
>> race and the first one writes into volatile `Executable.parameters` field
>> (doing _releasing store_) and the second thread reads non-null value from
>> the same field (doing acquiring read) then it must read exactly the same
>> value written into `hasRealParameterData` within `privateGetParameters()`.
>> The reason for this is that we assign `hasRealParameterData` before
>> _releasing store_.
>>
>> In the opposite case (_acquiring read_ reads null) the second thread writes
>> the value itself and returns it from the method so there is no change in
>> behavior.
>
> Сергей Цыпанов has updated the pull request incrementally with one additional
> commit since the last revision:
>
> 8288327: Inline privateGetParameters()
Changes requested by plevart (Reviewer).
src/java.base/share/classes/java/lang/reflect/Executable.java line 457:
> 455: private transient @Stable ParameterData parameterData;
> 456:
> 457: record ParameterData(@Stable Parameter[] parameters, boolean isReal)
> {}
Record fields are implicitly "trusted final", which means they don't need
@Stable annotation:
https://github.com/openjdk/jdk/blob/124c63c17c897404e3c5c3615d6727303e4f3d06/src/hotspot/share/ci/ciField.cpp#L240
-------------
PR: https://git.openjdk.org/jdk/pull/9143
