RFR: 8298853: JvmtiVTMSTransitionDisabler should support disabling one virtual thread transitions [v3]

[Serguei Spitsyn]

On Tue, 20 Dec 2022 10:22:03 GMT, Serguei Spitsyn <sspitsyn at openjdk.org> wrote:

>> This can be a separate RFE if the reason for it being a nosafepoint lock no longer holds. It would be cleaner to use a normal safepoint checking lock than to artificially make the thread safepoint-safe before using it.
>
> Agreed. I was thinking about a separate RFE. I started seeing some failures in the S/R related tests with the removed `ThreadBlockInVM` and `_no_safepoint_check_flag`. Need to investigated why. Otherwise, it seems to be working well.

As I see there can be some problems with the JVMTI Suspend/Resume but it is worth to investigate anyway.
So, I've filed an RFE:
[JDK-8299240](https://bugs.openjdk.org/browse/JDK-8299240): rank of JvmtiVTMSTransition_lock can be safepoint

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PR: https://git.openjdk.org/jdk/pull/11690