8372652: Re-enable LocalRandom clinit after monitor pinning improvements

[vish-chan]

This PR re-enables LocalRandom clinit after monitor pinning improvements.
Enabling this one would start printing random seeds, which is useful for test debugging.

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Progress

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Issue

• JDK-8372652: Re-enable LocalRandom clinit after monitor pinning improvements (Enhancement - P4)

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back vish-chan! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@vish-chan This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8372652: Re-enable LocalRandom clinit after monitor pinning improvements

Reviewed-by: shade

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At the time when this comment was updated there had been 218 new commits pushed to the master branch:

• 0c6d1b9: 8371759: Add missing @OverRide annotations in com.sun.imageio package
• 195b36f: 8372702: sun/security/pkcs11/tls/fips/FipsModeTLS.java does not compile after JDK-8367096
• f1d90b8: 8372134: ThreadLocalRandom no longer overrides nextGaussian
• ... and 215 more: https://git.openjdk.org/jdk/compare/00f2c38e373f5ae58ad6593cc7b9d53b9596eb17...master

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[openjdk]

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[vish-chan]

/label hotspot

[openjdk]

@vish-chan
The hotspot label was successfully added.

[mlbridge]

Webrevs

• 00: Full (8a82bacc)

[shipilev]

Looks fine to me. I suspect this one from @AlanBateman's Loom integration, maybe it was literally his addition? :)

[shipilev]

Also, you need to run the affected tests for extra safety. Looks like the entirety of vmTestbase needs to pass: make test TEST=vmTestbase/.

[AlanBateman]

Looks fine to me. I suspect this one from @AlanBateman's Loom integration, maybe it was literally his addition? :)

JEP 425 had many contributors, here's the original commit in the loom repo in 2020 from Leonid:
openjdk/loom@d6a26a5

The recent work for JDK 26 allows virtual threads to preempt/unmount while waiting for another thread to initialize a class but they do not allow a virtual thread to unmount while executing a class initializer (as there are VM frames on the stack).

I think I would need more context to know if the change proposed here is okay.

[vish-chan]

@shipilev jtreg:test/hotspot/jtreg/vmTestbase are passing locally.

[AlanBateman]

You'll need to test with JTREG_TEST_THREAD_FACTORY=Virtual to see if there are issues.

[vish-chan]

@AlanBateman I'm assuming running JTREG_TEST_THREAD_FACTORY=Virtual make test TEST=vmTestbase/ is enough?

[AlanBateman]

@AlanBateman I'm assuming running JTREG_TEST_THREAD_FACTORY=Virtual make test TEST=vmTestbase/ is enough?

I'll defer to @lmesnik for guidance on this.

[lmesnik]

Unfortunately, there are might be failure of execution vmTestbase/withJTREG_TEST_THREAD_FACTORY=Virtual`. So it enough ensure the your fix doesn't create new failures and timeouts.