RFR: 8318757: VM_ThreadDump asserts in interleaved ObjectMonitor::deflate_monitor calls [v7]

[Aleksey Shipilev]

On Fri, 10 Nov 2023 08:19:32 GMT, Stefan Karlsson <stefank at openjdk.org> wrote:

>> A safepointed monitor deflation pass can run interleaved with a paused async monitor deflation pass. The code is not written to handle that situation and asserts when it finds a DEFLATER_MARKER in the owner field. @pchilano also found other issues with having to monitor deflation passes interleaved. More info below ...
>
> Stefan Karlsson has updated the pull request incrementally with three additional commits since the last revision:
> 
>  - Remove the limit for deflation requests
>  - Remove reinitialization in test
>  - Update comments

This looks good to me. I have cosmetic comments about the tests.

test/hotspot/jtreg/runtime/Monitor/ConcurrentDeflation.java line 46:

> 44:     public static void main(String[] args) throws Exception {
> 45:         Thread thread_dumper  = new Thread(() -> dumpThreads());
> 46:         thread_dumper.start();

Here and later, the Java style is `threadDumper`, etc.

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Marked as reviewed by shade (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/16519#pullrequestreview-1724721135
PR Review Comment: https://git.openjdk.org/jdk/pull/16519#discussion_r1389360671