RFR 8215047: Task terminators do not complete termination in consistent state

[Zhengyu Gu]

Ping!

In addition to hotspot_gc tests (+/- UseOWSTTaskTerminator) on Linux 64, 
also ran vmTestbase_vm_gc (+/- UseOWSTTaskterminator) and submit tests.

Thanks,

-Zhengyu

On 1/3/19 10:49 AM, zgu at redhat.com wrote:
> Threads that enter termination protocol, should always see the same
> termination result, terminated or aborted. And terminator should
> always complete in one of two following states:
> 
> Terminated: _offered_termination == _n_threads (all threads arrived and
> terminated)
> Aborted:   _offered_termination = 0 (none of threads completed)
> 
> Current implementation does not guarantee that, so that, it can leave
> terminator in inconsistent states. The inconsistent states can trigger
> assertion failure when reset the terminator for reuse (vs.
> reset_for_reuse() method)
>   
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8215047
> Webrev: http://cr.openjdk.java.net/~zgu/JDK-8215047/webrev.00/index.htm
> l
> 
> Test:
> 
>    hotspot_gc on Linux x64 (fastdebug and release)
> 
> Thanks,
> 
> -Zhengyu
>