RFR: 8229169: False failure of GenericTaskQueue::pop_local on architectures with weak memory model

[Doerr, Martin]

Hi Jie,

thanks for the new webrev.
 
> The writer calls GenericTaskQueue<E, F, N>::pop_global to update
> _age._top with _age.cmpxchg(newAge, oldAge) [1] .
> I think it already contains the release (or storestore) barrier semantic.
Yes. I agree.

> What do you think?
Looks reasonable to me, but somebody from GC team should also take a look.

> Here is my reproducer to debug this issue:
> http://cr.openjdk.java.net/~jiefu/8229169/reproducer/
Maybe I didn't figure out how to run it correctly. Where's the source code for ClassLoaderGenerator.class?
Did you get the error while running javac?
It didn't crash on PPC64.

Best regards,
Martin