8334769: Shenandoah: Move CodeCache_lock close to its use in ShenandoahConcurrentNMethodIterator

[zhengyu123]

ShenandoahConcurrentNMethodIterator requires CodeCache_lock at begin and end of iteration.

Currently, the CodeCache_lock is acquired by their callers, which is not very obvious and readable. Let's move the lock inside the methods.

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Issue

• JDK-8334769: Shenandoah: Move CodeCache_lock close to its use in ShenandoahConcurrentNMethodIterator (Enhancement - P4)

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer)
• William Kemper (@earthling-amzn - Committer)
• Kelvin Nilsen (@kdnilsen - Author)

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[openjdk]

@zhengyu123 This change now passes all automated pre-integration checks.

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

8334769: Shenandoah: Move CodeCache_lock close to its use in ShenandoahConcurrentNMethodIterator

Reviewed-by: shade, wkemper, kdnilsen

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 38 new commits pushed to the master branch:

• b5d5896: 8335108: Build error after JDK-8333658 due to class templates
• 5883a20: 8334437: De-duplicate ProxyMethod list creation
• 8591eff: 8332103: since-checker - Add missing @ since tags to java.desktop
• 8374d16: 8335006: C2 SuperWord: add JMH benchmark VectorLoadToStoreForwarding.java
• 4ffc5e6: 8326705: Test CertMsgCheck.java fails to find alert certificate_required
• efb905e: 8334618: ubsan: support setting additional ubsan check options
• b2ac725: 8327380: Add tests for Shenandoah barrier expansion optimization
• f23295e: 8334600: TEST java/net/MulticastSocket/IPMulticastIF.java fails on linux-aarch64
• 741a0f3: 8334241: Adjust API docs side bar dimensions
• 4ce8822: 8334037: Local class creation in lambda in pre-construction context crashes javac
• ... and 28 more: https://git.openjdk.org/jdk/compare/5ac2149b7bde947886533bf5996d977bb8ec66f1...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.

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• hotspot-gc
• shenandoah

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[mlbridge]

Webrevs

• 00: Full (78ec7bb1)

[shipilev]

Agree, it looks cleaner that way, and has a symmetry with how ShenandoahCodeRootsIterator does it.

[shipilev]

@kdnilsen @earthling-amzn might need to take a look.

[earthling-amzn]

Looks good to me.

[kdnilsen]

Thanks.

[zhengyu123]

/integrate

Thanks, @shipilev @earthling-amzn and @kdnilsen

[openjdk]

Going to push as commit 4ebb771.
Since your change was applied there have been 40 commits pushed to the master branch:

• 817edcb: 8331411: Shenandoah: Reconsider spinning duration in ShenandoahLock
• bffc848: 8333755: NumberFormat integer only parsing breaks when format has suffix
• b5d5896: 8335108: Build error after JDK-8333658 due to class templates
• 5883a20: 8334437: De-duplicate ProxyMethod list creation
• 8591eff: 8332103: since-checker - Add missing @ since tags to java.desktop
• 8374d16: 8335006: C2 SuperWord: add JMH benchmark VectorLoadToStoreForwarding.java
• 4ffc5e6: 8326705: Test CertMsgCheck.java fails to find alert certificate_required
• efb905e: 8334618: ubsan: support setting additional ubsan check options
• b2ac725: 8327380: Add tests for Shenandoah barrier expansion optimization
• f23295e: 8334600: TEST java/net/MulticastSocket/IPMulticastIF.java fails on linux-aarch64
• ... and 30 more: https://git.openjdk.org/jdk/compare/5ac2149b7bde947886533bf5996d977bb8ec66f1...master

Your commit was automatically rebased without conflicts.

[openjdk]

@zhengyu123 Pushed as commit 4ebb771.

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