RFR: 8298059: Linked stack watermarks don't support nesting [v3]

[David Holmes]

On Tue, 6 Dec 2022 13:23:29 GMT, Erik Österlund <eosterlund at openjdk.org> wrote:

>> The KeepStackGCProcessedMark facility used to ensure a thread (possibly remote) remains fully processed in its scope, has not yet had to support nesting. As it turns out, they can now nest after JDK-8294924. So this patch adds support for nesting. Tested ZGC specific tests tier 1-8, general testing 1-3 and manually tested the two tests that failed and got problem listed.
>
> Erik Österlund has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Change from mtInternal to mtThread

Though now I'm looking at the full file, it is hard to tell how this new code interacts with the existing code that already utilises the lock.

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PR: https://git.openjdk.org/jdk/pull/11530