RFR: 8244679: JVM/TI GetCurrentContendedMonitor/contmon001 failed due to "(IsSameObject#3) unexpected monitor object: 0x000000562336DBA8" [v2]

[Serguei Spitsyn]

On Thu, 12 Nov 2020 08:11:10 GMT, Robbin Ehn <rehn at openjdk.org> wrote:

>> As the stack trace in the bug shows, we cannot load classes, since we may take a monitor.
>> Resulting in an unexpected result to GetCurrentContendedMonitor().
>> Trying to use some decent primitive, e.g. Wicket/Semaphore/.., without being implementation dependent means we must warm up every possible scenario, since it may use a new class.
>> Instead I here just use sleep + volatile for the barriers.
>> 
>> I cannot reproduce with these changes.
>> 
>> Chewing through T6 as most issues have been seen there - passed.
>
> Robbin Ehn has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fixed comment

Robbin, thank you for nice analysis in the the bug report.
The fix looks good.
Thanks,
Serguei

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Marked as reviewed by sspitsyn (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/1177