8320687: sun.jvmstat.monitor.MonitoredHost.getMonitoredHost() throws unexpected exceptions when invoked concurrently

[satyenme]

Backporting JDK-8320687: sun.jvmstat.monitor.MonitoredHost.getMonitoredHost() throws unexpected exceptions when invoked concurrently. The fix proposes to guard the usage of the shared ServiceLoader instance through the monitoredHosts object monitor. Adds test. Ran GHA Sanity Checks, local Tier 1, 2, and 3, and new test/jdk/sun/jvmstat/monitor/MonitoredVm/ConcurrentGetMonitoredHost.java tests. Patch is almost clean (copyright header is slightly different).

---

Progress

• JDK-8320687 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8320687: sun.jvmstat.monitor.MonitoredHost.getMonitoredHost() throws unexpected exceptions when invoked concurrently (Bug - P4 - Approved)

Reviewing

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$ git fetch https://git.openjdk.org/jdk17u-dev.git pull/3531/head:pull/3531
$ git checkout pull/3531

Update a local copy of the PR:
$ git checkout pull/3531
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/3531/head

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Checkout this PR locally:
$ git pr checkout 3531

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https://git.openjdk.org/jdk17u-dev/pull/3531.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back ssubramaniam! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@satyenme 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:

8320687: sun.jvmstat.monitor.MonitoredHost.getMonitoredHost() throws unexpected exceptions when invoked concurrently

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 117 new commits pushed to the master branch:

• d132468: 8325680: Uninitialised memory in deleteGSSCB of GSSLibStub.c:179
• 18d5503: 8321479: java -D-D crashes
• 6b4fe75: 8314120: Add tests for FileDescriptor.sync
• ... and 114 more: https://git.openjdk.org/jdk17u-dev/compare/96e8c5652053e4ee424d73834dc55d97838c6eea...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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[openjdk]

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

[openjdk]

⚠️ @satyenme 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 (83dc516d)

[satyenme]

/approval request for backport. Guards the usage of the shared ServiceLoader instance through the monitoredHosts object monitor to avoid sun.jvmstat.monitor.MonitoredHost.getMonitoredHost() throwing unexpected exceptions when invoked concurrently.

Risk: Low. Tip change was merged in December 2023 and adds a test to confirm correct functionality.

Testing:

• GHA Sanity Checks
• Tier 1, 2, and 3 tests locally

[openjdk]

@satyenme
8320687: The approval request has been created successfully.

[satyenme]

/integrate

[openjdk]

@satyenme
Your change (at version 83dc516) is now ready to be sponsored by a Committer.

[phohensee]

/sponsor

[openjdk]

Going to push as commit f153824.
Since your change was applied there have been 121 commits pushed to the master branch:

• bd69dee: 8319690: [AArch64] C2 compilation hits offset_ok_for_immed: assert "c2 compiler bug"
• 2636676: 8318700: MacOS Zero cannot run gtests due to wrong JVM path
• 1133187: 8314236: Overflow in Collections.rotate
• ... and 118 more: https://git.openjdk.org/jdk17u-dev/compare/96e8c5652053e4ee424d73834dc55d97838c6eea...master

Your commit was automatically rebased without conflicts.

[openjdk]

@phohensee @satyenme Pushed as commit f153824.

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

[GoeLin]

Hi @phohensee @satyenme

Your patch breaks testing. The test you submitted uses Java that can not be compiled with 17. Please fix or back out asap!

You are supposed to run tests included in the change before you do a backport!!! You claim you did so, so why is the syntax wrong?

  try (ExecutorService executor = Executors.newCachedThreadPool()) {
                         ^
(ExecutorService cannot be converted to AutoCloseable)

1 error
result: Failed. Compilation failed: Compilation failed

[GoeLin]

@phohensee @satyenme, any comments?

[phohensee]

Apologies for not running the test myself and causing a problem. Shall I resubmit?

[phohensee]

See #3593.

[GoeLin]

Yes, you can resubmit it. No objections if everything works :)

[phohensee]

Thanks, @GoeLin, looks like it does :)