8366980: TestTransparentHugePagesHeap.java fails when run with -UseCompressedOops

[stefank]

The new test TestTransparentHugePagesHeap.java added in JDK-8366434 fails when run with -UseCompressedOops.

The reason for this is that the address printed as the start of the heap in the pagesize logging is not the start of the mapping. So we fail to find the mapping when scanning the SMAPS file.

There reason why this happens is that Linux has merged the memory area for the heap with some other memory. Sometimes it is the marking bitmaps and sometimes it's just malloc that mapped some memory.

I propose that we change the test to find the smaps memory area that contains the start address of the heap and verify that that area is THP eligible.

I'm using BigInteger to represent the parsed addresses to skip having to deal with negative values in longs.

Tested locally with the reproducer. I'm also testing with tier1 and the tier that found this issue.

The fix is localized in TestTransparentHugePagesHeap.java so that it can easily be incorporated into a backport of JDK-8366434.

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Issue

• JDK-8366980: TestTransparentHugePagesHeap.java fails when run with -UseCompressedOops (Bug - P3)

Reviewers

• Axel Boldt-Christmas (@xmas92 - Reviewer)
• Thomas Schatzl (@tschatzl - Reviewer)

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[bridgekeeper]

👋 Welcome back stefank! 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]

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

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

8366980: TestTransparentHugePagesHeap.java fails when run with -UseCompressedOops

Reviewed-by: aboldtch, tschatzl

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At the time when this comment was updated there had been 37 new commits pushed to the master branch:

• 0aee7bf: 8367048: RISC-V: Correct pipeline descriptions of the architecture
• 4ec63e8: 8366850: Test com/sun/jdi/JdbStopInNotificationThreadTest.java failed
• 81a1e8e: 8364936: Shenandoah: Switch nmethod entry barriers to conc_instruction_and_data_patch
• ... and 34 more: https://git.openjdk.org/jdk/compare/ceacf6f7852514dc9877cfe284f9550c179d913a...master

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[mlbridge]

Webrevs

• 01: Full - Incremental (97187a81)
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[xmas92]

lgtm.

[stefank]

Thanks for the reviews!
/integrate

[openjdk]

Going to push as commit 703d930.
Since your change was applied there have been 67 commits pushed to the master branch:

• 4d4e51c: 8365483: Test sun/rmi/runtime/Log/6409194/NoConsoleOutput.java sometimes fails
• edae355: 8246325: Add DRYRUN facility to SetupExecute
• 33244c8: 8344030: Improved handling of TOOLCHAIN_PATH
• ... and 64 more: https://git.openjdk.org/jdk/compare/ceacf6f7852514dc9877cfe284f9550c179d913a...master

Your commit was automatically rebased without conflicts.

[openjdk]

@stefank Pushed as commit 703d930.

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