8365571: GenShen: PLAB promotions may remain disabled for evacuation threads

[earthling-amzn]

Mutators and GC workers have old generation LABs for promotions and old generation evacuations. Priority is given to old evacuations by using a promotion budget. Once the promotion budget is exhausted, a thread local flag is set to disable further promotions (the LAB can still be used for old evacuations). This thread local flag is meant to be cleared to allow all threads to resume promotions on the next cycle. However, this flag is only reset for workers that perform thread root evacuations, which may not be the same workers that perform subsequent evacuations. This patch clears the flag for all threads when their LABs are retired at the end of evacuation.

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Issue

• JDK-8365571: GenShen: PLAB promotions may remain disabled for evacuation threads (Bug - P4)

Reviewers

• Kelvin Nilsen (@kdnilsen - Committer)
• Y. Srinivas Ramakrishna (@ysramakrishna - Reviewer)
• Aleksey Shipilev (@shipilev - Reviewer)

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[openjdk]

@earthling-amzn This change now passes all automated pre-integration checks.

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8365571: GenShen: PLAB promotions may remain disabled for evacuation threads

Reviewed-by: kdnilsen, ysr, shade

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At the time when this comment was updated there had been 14 new commits pushed to the master branch:

• e3aeebe: 8365468: EagerJVMCI should only apply to the CompilerBroker JVMCI runtime
• 6fb6f3d: 8361638: java.lang.classfile.CodeBuilder.CatchBuilder should not throw IllegalArgumentException for representable exception handlers
• 44b19c0: 8365532: java/lang/module/ModuleReader/ModuleReaderTest.testImage fails
• ... and 11 more: https://git.openjdk.org/jdk/compare/e320162815d529bc65cd058b34ec39d60d032ce7...master

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[mlbridge]

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[kdnilsen]

Thank you for much improved code structure, and for fixing this bug.

Would be nice to share any improved performance results with this fix in place.

[earthling-amzn]

@ysramakrishna - the performance test results show no regressions. The level of detail we need to see the effect of the changes isn't enabled by default in the release testing.

/integrate

[openjdk]

Going to push as commit 08db4b9.
Since your change was applied there have been 19 commits pushed to the master branch:

• dbae90c: 8364723: Sort share/interpreter includes
• 059b49b: 8365244: Some test control variables are undocumented in doc/testing.md
• b6d5f49: 8365296: Build failure with Clang due to -Wformat warning after JDK-8364611
• ... and 16 more: https://git.openjdk.org/jdk/compare/e320162815d529bc65cd058b34ec39d60d032ce7...master

Your commit was automatically rebased without conflicts.

[openjdk]

@earthling-amzn Pushed as commit 08db4b9.

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