RFR (S) 8224151: Test vmTestbase/nsk/sysdict/vm/stress/chain/chain007/chain007.java might hang with release binaries

[Erik Österlund]

Hi Coleen,

Could you please add Atomic::load() on the CLD::next getter used by the 
iterator? No need for new webrev. Should remove the lock on the reader 
side in the future by making the unloading list use a different next 
pointer. Then the reader side locking won't really do anything for us.

Thanks,
/Erik

On 2019-06-06 03:53, coleen.phillimore at oracle.com wrote:
> Summary: Fix deadlock on ClassLoaderDataGraph_lock and g1 
> clear_claimed_marks.
> 
> Thank you to Stefan for finding the deadlock and Thomas for suggestions 
> on the fix, plus text for comments.
> 
> Tested with this test 100s of times, tier1-3 and tier6 almost complete.
> 
> open webrev at http://cr.openjdk.java.net/~coleenp/2019/8224151.01/webrev
> bug link https://bugs.openjdk.java.net/browse/JDK-8224151
> 
> Thanks,
> Coleen