8283710: JVMTI: Use BitSet for object marking

[rkennke]

This is a backport of JDK-8283710 to 17u.

There have been contextual differences around the declaration of _bitset and corresponding contextual differences in the constructor: the field _dead_objects did not exist in jdk19, but does exist in jdk17u. There also have been differences in the large block that has been removed (the whole of ObjectMarker and related code). Other than that, the backport has been clean and straightforward.

Testing:

• tier1
• tier2
• serviceability/jvmti
• serviceability/jdwp
• vmTestbase/nsk/jvmti
• vmTestbase/msk/jdwp

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8283710: JVMTI: Use BitSet for object marking (Enhancement - P4)

Reviewers

• Paul Hohensee (@phohensee - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk17u-dev.git pull/1602/head:pull/1602
$ git checkout pull/1602

Update a local copy of the PR:
$ git checkout pull/1602
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/1602/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 1602

View PR using the GUI difftool:
$ git pr show -t 1602

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk17u-dev/pull/1602.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back rkennke! 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]

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

[mlbridge]

Webrevs

• 01: Full - Incremental (770f70cd)
• 00: Full (28702844)

[phohensee]

GHA failure is a known RISC-V issue.

[openjdk]

@rkennke 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:

8283710: JVMTI: Use BitSet for object marking

Reviewed-by: phh

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 16 new commits pushed to the master branch:

• bf70c43: 8302161: Upgrade jQuery UI to version 1.13.2
• 504ec27: 8305670: Performance regression in LockSupport.unpark with lots of idle threads
• e8a8a2d: 8292683: Remove BadKeyUsageTest.java from Problem List
• 68b3f47: 8275662: remove test/lib/sun/hotspot
• 4f4e042: 8281717: Cover logout method for several LoginModule
• baf2841: 8303279: C2: crash in SubTypeCheckNode::sub() at IGVN split if
• c2543ea: 8276333: jdk/jfr/event/oldobject/TestLargeRootSet.java failed "assert(!contains(edge->reference())) failed: invariant"
• 34da7e2: 8275415: Prepare Leak Profiler for Lilliput
• eb7900a: 8306881: Update FreeType to 2.13.0
• 95a89ed: 8286623: Bundle zlib by default with JDK on macos aarch64
• ... and 6 more: https://git.openjdk.org/jdk17u-dev/compare/a19156d9ebfb5e0838ded6328a28df3e26981c14...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.

[RealCLanger]

I will run this through our nigthlies to verify...