[14] RFR 8235829: graal crashes with Zombie.java test

[Robbin Ehn]

Hi Coleen,

I looked at v2:
http://cr.openjdk.java.net/~coleenp/2019/8235829.01/webrev

Seems good.

But we do a lot of work to keep the nmethod alive while in queue.
Instead we should try copy the data from nmethod and enqueue this copy.
Thus not having to keep the nmethod alive.
Not for this change-set, but a potential future simplification.

Thanks, Robbin

On 12/16/19 12:41 PM, coleen.phillimore at oracle.com wrote:
> Summary: Start ServiceThread before compiler threads, and run nmethod barriers 
> for zgc before adding to the service thread queue, or posting the events on the 
> java thread queue.
> 
> See bug for description of the problems found with the new Zombie.java test.
> 
> open webrev at http://cr.openjdk.java.net/~coleenp/2019/8235829.01/webrev
> bug link https://bugs.openjdk.java.net/browse/JDK-8235829
> 
> Ran tier1 all platforms, and tier2-8 testing, as well as rerunning original test 
> failure from bug https://bugs.openjdk.java.net/browse/JDK-8173361.
> 
> Thanks,
> Coleen