8360540: nmethod entry barriers of new nmethods should be disarmed

[rm-gh-8]

Backporting JDK-8360540: nmethod entry barriers of new nmethods should be disarmed

This PR addresses an optimization gap where nmethod entry barriers are unnecessarily executed for new methods in non-ZGC/non-ShenandoahGC collectors. Since JDK-8290025, all GCs use nmethod entry barriers, but only ZGC and ShenandoahGC properly disarm these barriers for new nmethods before first execution. The fix adds disarm calls for other GCs to match ZGC/ShenandoahGC behavior.

This backport has internal demand.

Ran related tests on linux-x64, linux-aarch64, macos-aarch64 and windows-x64:

make test TEST=test/hotspot/jtreg/vmTestbase/gc

Results attached:

linux-x64-specific-test.log
macos-aarch64-specific-test.log
windows-x64-specific-test.log
linux-aarch64-specific-test.log

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Progress

• Change must not contain extraneous whitespace
• JDK-8360540 needs maintainer approval
• Commit message must refer to an issue

Warning

 ⚠️ Found leading lowercase letter in issue title for 8360540: nmethod entry barriers of new nmethods should be disarmed

Issue

• JDK-8360540: nmethod entry barriers of new nmethods should be disarmed (Enhancement - P3 - Requested)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/140/head:pull/140
$ git checkout pull/140

Update a local copy of the PR:
$ git checkout pull/140
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/140/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 140

View PR using the GUI difftool:
$ git pr show -t 140

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/140.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

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[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

⚠️ @rm-gh-8 This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (aedbdcde)

[rm-gh-8]

/approval request for backport of JDK-8360540: nmethod entry barriers of new nmethods should be disarmed

The fix adds disarm calls for other GCs (G1, Parallel, Serial) to match ZGC/ShenandoahGC behavior.

This backport has internal demand.

Medium-high risk - Incorrect disarming could affect GC safety or concurrent collection correctness.

[openjdk]

@rm-gh-8
8360540: The approval request has been created successfully.

[rm-gh-8]

Please note that https://bugs.openjdk.org/browse/JDK-8365976 will need to follow this PR.

[rm-gh-8]

When JDK-8360540 is merged, G1 full garbage collection no longer marks nmethods that are currently on the stack, which could lead to premature code eviction issues, so a dependent PR is needed