8266497: Remove unnecessary EMCP liveness indication

[coleenp]

Marking running_emcp for Method* is unnecessary. We can set/clear breakpoints in all old emcp methods because they're not deallocated until none are running. See longer explanation in the CR.

Tested with tier1-6, tiers 7,8 are running and 98% passing.

---

Progress

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Issue

• JDK-8266497: Remove unnecessary EMCP liveness indication

Reviewers

• Ioi Lam (@iklam - Reviewer)
• David Holmes (@dholmes-ora - Reviewer)
• Serguei Spitsyn (@sspitsyn - Reviewer)

Reviewing

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (c1c1a7b2)

[coleenp]

/label remove hotspot
/label add hotspot-runtime

[openjdk]

@coleenp
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[openjdk]

@coleenp
The hotspot-runtime label was successfully added.

[iklam]

Looks reasonable to me.

[openjdk]

@coleenp 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:

8266497: Remove unnecessary EMCP liveness indication

Reviewed-by: iklam, dholmes, sspitsyn

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

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

• b172555: 8266171: -Warray-bounds happens in imageioJPEG.c
• 8bcebe7: 8265505: findsym does not work on remote debug server
• b88785d: 8266038: Move newAddress() to JVMDebugger
• 2c53654: 8266179: [macos] jpackage should specify architecture for produced pkg files
• d282799: 8255566: Add size validation when parsing values from VersionProps
• 61365d5: 8266465: Add wildcard to JTwork/JTreport exclude in jib-profiles.js
• f00b70e: 8266527: RandomTestCoverage.java failing due to API removal
• c53dee7: 8266227: Fix help text for --mac-signing-keychain
• 80323b7: 8261169: Upgrade HarfBuzz to the latest 2.8.0
• 9c4efdd: 8263124: Missed initialization of baselineY in sun.font.StrikeMetrics
• ... and 4 more: https://git.openjdk.java.net/jdk/compare/05e601748a35de02a33721199a00a3d6c335c6d9...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[coleenp]

Thanks Ioi, and thanks for updating the description.

[dholmes-ora]

Hi Coleen,

Seems reasonable. Nice simplification too!

Thanks,
David

[sspitsyn]

Hi Coleen,

This looks good to me in general.
I'm a little bit puzzled why the check emcp_method_count != 0 is needed at the line:
4005 if (emcp_method_count != 0 && obsolete_method_count != 0 &&

Suppose, the emcp_method_count is equal to 0.
Then do we really want to skip marking all the methods of this InstanceKlass as obsolete?
Most likely, I'm missing something.

Thanks,
Serguei

[coleenp]

@sspitsyn I think you're right here. If all the newly old methods are obsolete, then we should mark all the methods in the previous versions as obsolete and not skip this. I'll file an issue to investigate this because it's always been this way (and could use a test also). It's too risky to change here. Thanks for the code review!

[coleenp]

Thanks for the code review, David.
/integrate

[openjdk]

@coleenp Since your change was applied there have been 25 commits pushed to the master branch:

• 6ba911d: 8266498: Make debug ps() call print_stack
• ef0f693: 8266499: Delete dead code in aarch64.ad
• 71d0858: 8266522: Shenandoah: Shenandoah LRB calls wrong runtime barrier on aarch64
• 0ac84d1: 8266506: [aix] Treat mapping attempt too close to BRK as a mapping error
• 02cdd6e: 8266419: [aix] in mmap mode, os::attempt_reserve_memory_at() fails to handle wrong mapping address
• 250b45a: 8266222: [aix] In mmap-mode, partial releases with os::release_memory may trash internal bookkeeping
• 65ce4d2: 8266491: Remove resolve and obj_equals leftovers from BarrierSetAssembler
• a8046c9: 8266436: Synthetic constructor trees have non-null return type
• c9873c4: 8260621: (jrtfs) ThreadLocal memory leak in ImageBufferCache when using jrtfs
• 82768d9: 8221503: vmTestbase/nsk/jdb/eval/eval001/eval001.java fails with: com.sun.jdi.InvalidTypeException: Can't assign double[][][] to double[][][]
• ... and 15 more: https://git.openjdk.java.net/jdk/compare/05e601748a35de02a33721199a00a3d6c335c6d9...master

Your commit was automatically rebased without conflicts.

Pushed as commit a05e8e2.

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[sspitsyn]

Thanks, Coleen! I agree, it is better to file a new bug.