RFR: 8062771: Core reflection should use final fields whenever possible

[Joel Borggrén-Franck]

Hi Peter,

Yes, please file a separate issue and a RFR.

cheers
/Joel

On 10 nov 2014, at 17:13, Peter Levart <peter.levart at gmail.com> wrote:

> On 11/07/2014 11:48 PM, Martin Buchholz wrote:
>> Hi Joel,
>> 
>> Thanks for volunteering.  I foisted all I have in
>> 
>> https://bugs.openjdk.java.net/browse/JDK-8064391
>> 
>> I volunteer to be your reviewer for the backports.
> 
> Hi Martin,
> 
> Sorry I haven't checked this earlier, but there are still some data races left-behind:
> 
> http://cr.openjdk.java.net/~plevart/jdk9-dev/GenericsReflectionRaces/webrev.01/
> 
> Mainly the fact that lazy initialization uses arrays which are published unsafely.
> 
> Would this need a separate issue. For example: "Core reflection should use volatile fields whenever necessary" ?
> 
> 
> Regards, Peter
> 
>> 
>> On Fri, Nov 7, 2014 at 1:36 PM, Joel Borggrén-Franck
>> <joel.franck at oracle.com> wrote:
>>> Hi Martin,
>>> 
>>> Thanks for the clarification.
>>> 
>>> On 6 nov 2014, at 20:51, Martin Buchholz <martinrb at google.com> wrote:
>>> 
>>>> Hi Joel,
>>>> 
>>>> On Thu, Nov 6, 2014 at 2:48 AM, Joel Borggrén-Franck
>>>> <joel.franck at oracle.com> wrote:
>>>>> Hi,
>>>>> 
>>>>> I’m having a hard time following this thread, which webrev has been updated, for which release, fixing which issue?
>>>> I am submitting the changeset for JDK-8062771, adding the finals and
>>>> the (failed reproduction) test.
>>>> Hopefully there will be followon changes to add even more thread safety.
>>>> 
>>> Great.
>>> 
>>> Are we sure the accidental fix of making ClassRepository volatile is good on all platforms? I can’t establish the happens before relations that would prove the fix but then again I’m not an expert on concurrency.
>>> 
>>>>> Martin, as far as I can see you are the only one of us who has replied to this thread who is a jdk7u committer (or reviewer).
>>>> I am entirely in favor of having more reviewers.
>>>> 
>>>> We are not planning to push these into jdk7u or jdk8u ourselves, but
>>>> we are willing to help anyone who wants to take on that task.  Joel,
>>>> are you volunteering?
>>>> We believe all versions of stock openjdk still have (rarely seen)
>>>> thread safety issues in core reflection. We have applied changes
>>>> locally at Google to fix those.
>>>> 
>>> I’ll take care of 8u, and I can hunt down someone to fix this in 7u if we can find a suitable reviewer (sigh).
>>> 
>>> cheers
>>> /Joel
>>> 
>>> 
>