8279488: ProcessBuilder inherits contextClassLoader when spawning a process reaper thread

[RogerRiggs]

The thread factory used to create the process reaper threads unnecessarily inherits the callers thread context classloader.
The result is retention of the class loader.

The thread factory used for the pool of process reaper threads is modified to use an InnocuousThread with a given stacksize.
The test verifies that the process reaper threads have a null context classloader.

---

Progress

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Issue

• JDK-8279488: ProcessBuilder inherits contextClassLoader when spawning a process reaper thread

Reviewers

• Alan Bateman (@AlanBateman - Reviewer)

Reviewing

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[bridgekeeper]

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[openjdk]

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[mlbridge]

Webrevs

• 01: Full - Incremental (fd3faa9d)
• 00: Full (3e64a424)

[RogerRiggs]

@AlanBateman Can you take a look at this use of InnocuousThread. Thanks

[RogerRiggs]

Please review this use of InnocuousThread. Tnx

[bridgekeeper]

@RogerRiggs This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[RogerRiggs]

Please Review.

[RogerRiggs]

@AlanBateman Please review and approve

[openjdk]

@RogerRiggs 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:

8279488: ProcessBuilder inherits contextClassLoader when spawning a process reaper thread

Reviewed-by: alanb

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 824 new commits pushed to the master branch:

• a577656: 8282943: Unused weird key in compiler.properties
• 7f2a3ca: 8281561: Disable http DIGEST mechanism with MD5 and SHA-1 by default
• 0c472c8: 8283756: (zipfs) ZipFSOutputStreamTest.testOutputStream should only check inflated bytes
• d6fa8b0: 8283469: Don't use memset to initialize members in FileMapInfo and fix memory leak
• 8567266: 8283683: Make ThreadLocalRandom a final class
• f4eaa16: 8283728: jdk.hotspot.agent: Wrong location for RISCV64ThreadContext.java
• cdef087: 8283727: P11KeyGenerator has import statement with two semicolons after JDK-8267319
• 7f12537: 8283558: Parallel: Pass PSIsAliveClosure to ReferenceProcessor constructor
• 66f1da1: 8281222: ciTypeFlow::profiled_count fails "assert(0 <= i && i < _len) failed: illegal index"
• c2c0cb2: 8282668: HotSpot Style Guide should permit unrestricted unions
• ... and 814 more: https://git.openjdk.java.net/jdk/compare/fef8f2d30004ea75c663752ae6c61b214fb8abc8...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.

[RogerRiggs]

/integrate

[openjdk]

Going to push as commit f0282d7.
Since your change was applied there have been 824 commits pushed to the master branch:

• a577656: 8282943: Unused weird key in compiler.properties
• 7f2a3ca: 8281561: Disable http DIGEST mechanism with MD5 and SHA-1 by default
• 0c472c8: 8283756: (zipfs) ZipFSOutputStreamTest.testOutputStream should only check inflated bytes
• d6fa8b0: 8283469: Don't use memset to initialize members in FileMapInfo and fix memory leak
• 8567266: 8283683: Make ThreadLocalRandom a final class
• f4eaa16: 8283728: jdk.hotspot.agent: Wrong location for RISCV64ThreadContext.java
• cdef087: 8283727: P11KeyGenerator has import statement with two semicolons after JDK-8267319
• 7f12537: 8283558: Parallel: Pass PSIsAliveClosure to ReferenceProcessor constructor
• 66f1da1: 8281222: ciTypeFlow::profiled_count fails "assert(0 <= i && i < _len) failed: illegal index"
• c2c0cb2: 8282668: HotSpot Style Guide should permit unrestricted unions
• ... and 814 more: https://git.openjdk.java.net/jdk/compare/fef8f2d30004ea75c663752ae6c61b214fb8abc8...master

Your commit was automatically rebased without conflicts.

[openjdk]

@RogerRiggs Pushed as commit f0282d7.

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