RFR: 8261759: ZGC: ZWorker Threads Continue Marking After System.exit() called [v4]

[Per Liden]

On Mon, 26 Apr 2021 11:50:48 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

>> Per Liden has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Add comment to macro
>
> Marked as reviewed by ayang (Committer).

Thanks @albertnetymk and @kstefanj for reviewing!

-------------

PR: https://git.openjdk.java.net/jdk/pull/3453