JDK-8303071: Memory leaks in libjdwp

[jcking]

Fix minor memory leaks in libjdwp.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
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• Commit message must refer to an issue

Issue

• JDK-8303071: Memory leaks in libjdwp

Reviewers

• Serguei Spitsyn (@sspitsyn - Reviewer)

Reviewing

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[openjdk]

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[mlbridge]

Webrevs

• 01: Full - Incremental (a2417376)
• 00: Full (00c5140a)

[sspitsyn]

It looks good.
Thank you for taking care about it.
Thanks,
Serguei

[openjdk]

@jcking 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:

8303071: Memory leaks in libjdwp

Reviewed-by: 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 36 new commits pushed to the master branch:

• fcaf871: 8302028: Port fdlibm atan2 to Java
• 07e976a: 8303081: Serial: Remove unused VM_MarkSweep
• 8de841d: 8302667: Improve message format when failing to load symbols or libraries
• f893d23: 8303024: (fs) WindowsFileSystem.supportedFileAttributeViews can use Set.of
• d7ada66: 8303084: G1 Heap region liveness verification has inverted return value
• 5d7e7e2: 8302760: Improve liveness/remembered set verification for G1
• b0e0f37: 8303067: G1: Remove unimplemented G1FullGCScope::heap_transition
• 1a62a12: 8302880: Fix includes in g1ConcurrentMarkObjArrayProcessor files
• ee37af4: 8302975: Remove redundant mark verification during G1 Full GC
• 83bea26: 8300575: JVMTI support when using alternative virtual thread implementation
• ... and 26 more: https://git.openjdk.org/jdk/compare/10b4cc9eb49c14a6be03b3f53e97037529169ed1...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.

[jcking]

Tests look unrelated and seem to be failing in other PRs.

[jcking]

/integrate

[openjdk]

Going to push as commit 2cf8b86.
Since your change was applied there have been 40 commits pushed to the master branch:

• f113b04: 8302927: Unproblemlist Fuzz.java from ProblemList-zgc.txt again
• 1bab93b: 8303073: (bf) Temporarily reinstate private DirectByteBuffer(long, int) constructor
• 221f346: 8303047: avoid NULL after 8301661
• 23e9d9d: 8302811: NMT.random_reallocs_vm fails if NMT is off
• fcaf871: 8302028: Port fdlibm atan2 to Java
• 07e976a: 8303081: Serial: Remove unused VM_MarkSweep
• 8de841d: 8302667: Improve message format when failing to load symbols or libraries
• f893d23: 8303024: (fs) WindowsFileSystem.supportedFileAttributeViews can use Set.of
• d7ada66: 8303084: G1 Heap region liveness verification has inverted return value
• 5d7e7e2: 8302760: Improve liveness/remembered set verification for G1
• ... and 30 more: https://git.openjdk.org/jdk/compare/10b4cc9eb49c14a6be03b3f53e97037529169ed1...master

Your commit was automatically rebased without conflicts.

[openjdk]

@jcking Pushed as commit 2cf8b86.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

[dholmes-ora]

Just a sanity check here. That memory was allocated using *callback->alloc not jvmtiAllocate - is it correct to release with jvmtiDeallocate?

[jcking]

callback->alloc is jvmtiAllocate and callback->free is jvmtiDeallocate. It is setup in transport.c, which is also the one which frees. So it is fine in this case.

[dholmes-ora]

Thanks! Now I can join the dots there.

[plummercj]

Approved.

@jcking In the future please wait for a second review before pushing any hotspot related changes unless the reviewer agrees that the changes are trivial. thanks.