8273381: Assert in PtrQueueBufferAllocatorTest.stress_free_list_allocator_vm

[kimbarrett]

Please review this fix of the test, eliminating a race that could
unexpectedly leave buffers in the "completed" list after all the threads
have shut down.

Testing:
mach5 tier1

---

Progress

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Issue

• JDK-8273381: Assert in PtrQueueBufferAllocatorTest.stress_free_list_allocator_vm

Reviewers

• Stefan Johansson (@kstefanj - Reviewer)
• Thomas Schatzl (@tschatzl - Reviewer)

Reviewing

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[mlbridge]

Webrevs

• 00: Full (c7177c5d)

[kstefanj]

Lgtm

[openjdk]

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

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

8273381: Assert in PtrQueueBufferAllocatorTest.stress_free_list_allocator_vm

Reviewed-by: sjohanss, tschatzl

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At the time when this comment was updated there had been 1 new commit pushed to the master branch:

• a5080ef: 8272564: Incorrect attribution of method invocations of Object methods on interfaces

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[tschatzl]

Lgtm apart from the mentioned (imho) comment inaccuracy.

[tschatzl]

s/avoid/handle/ (or something similar).

The change does not eliminate (or avoids) the race, but handles the (not logic-breaking) results of the race.

[tschatzl]

Suggested change

	// To avoid a race that could leave buffers in the list after this
	// To handle a benign race that could leave buffers in the list after this

[kimbarrett]

The race involved is not a benign data race, it's a logic race that's not at all benign. I could describe the race in more detail if you want.

[tschatzl]

I meant "benign" wrt to what is actually tested (functionality of the ptrqueuebuffer), but you are right about that my suggestion is the wrong wording. Just leave it as is then.

Thomas

[kimbarrett]

Thanks for reviews @kstefanj and @tschatzl .

[kimbarrett]

/integrate

[openjdk]

Going to push as commit c80a612.
Since your change was applied there have been 26 commits pushed to the master branch:

• 9759fcb: 8274496: Use String.contains() instead of String.indexOf() in java.desktop
• cdf8930: 8274625: Search field placeholder behavior
• df125f6: 8273410: IR verification framework fails with "Should find method name in validIrRulesMap"
• c74726d: 8274730: AArch64: AES/GCM acceleration is broken by the fix for JDK-8273297
• 2faced0: 8274738: ZGC: Use relaxed atomic load when reading bits in the live map
• 8a4d2b4: 8274680: Remove unnecessary conversion to String in java.desktop
• 986ee5d: 8274670: Improve version string handling in SA
• df7b0c7: 8274715: Implement forEach in Collections.CopiesList
• d4e8712: 8274797: ProblemList resourcehogs/serviceability/sa/TestHeapDumpForLargeArray.java on macosx-x64
• 4726267: 8274642: jdk/jshell/CommandCompletionTest.java fails with NoSuchElementException after JDK-8271287
• ... and 16 more: https://git.openjdk.java.net/jdk/compare/a914ee72167f642b76b1c1cdddd7ff0698d061cc...master

Your commit was automatically rebased without conflicts.

[openjdk]

@kimbarrett Pushed as commit c80a612.

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