8289439: Clarify relationship between ThreadStart/ThreadEnd and can_support_virtual_threads capability

[AlanBateman]

The description of the ThreadStart/End events in the JVM TI spec needs rewording to make it clearer when these events are sent for virtual threads and when VirtualThreadXXX events are sent instead.

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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
• Change requires a CSR request to be approved

Issues

• JDK-8289439: Clarify relationship between ThreadStart/ThreadEnd and can_support_virtual_threads capability
• JDK-8289574: Clarify relationship between ThreadStart/ThreadEnd and can_support_virtual_threads capability (CSR)

Reviewers

• David Holmes (@dholmes-ora - Reviewer)
• Daniel D. Daugherty (@dcubed-ojdk - Reviewer)
• Serguei Spitsyn (@sspitsyn - Reviewer)
• Chris Plummer (@plummercj - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk19 pull/94/head:pull/94
$ git checkout pull/94

Update a local copy of the PR:
$ git checkout pull/94
$ git pull https://git.openjdk.org/jdk19 pull/94/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 94

View PR using the GUI difftool:
$ git pr show -t 94

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk19/pull/94.diff

[bridgekeeper]

👋 Welcome back alanb! 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]

@AlanBateman The following labels will be automatically applied to this pull request:

• hotspot
• serviceability

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing lists. If you would like to change these labels, use the /label pull request command.

[AlanBateman]

/label remove hotspot

[openjdk]

@AlanBateman
The hotspot label was successfully removed.

[AlanBateman]

/csr

[openjdk]

@AlanBateman has indicated that a compatibility and specification (CSR) request is needed for this pull request.

@AlanBateman please create a CSR request for issue JDK-8289439 with the correct fix version. This pull request cannot be integrated until the CSR request is approved.

[mlbridge]

Webrevs

• 00: Full (e8f91aee)

[dholmes-ora]

This seems fine to me.

[dcubed-ojdk]

Thumbs up.

[sspitsyn]

Looks good.
Thanks,
Serguei

[openjdk]

@AlanBateman 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:

8289439: Clarify relationship between ThreadStart/ThreadEnd and can_support_virtual_threads capability

Reviewed-by: dholmes, dcubed, sspitsyn, cjplummer

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 17 new commits pushed to the master branch:

• 0b6fd48: 8288128: S390X: Fix crashes after JDK-8284161 (Virtual Threads)
• 30e134e: 8289091: move oop safety check from SharedRuntime::get_java_tid() to JavaThread::threadObj()
• 29ea642: 8287847: Fatal Error when suspending virtual thread after it has terminated
• f640fc5: 8067757: Incorrect HTML generation for copied javadoc with multiple @throws tags
• 0dff327: 8289569: [test] java/lang/ProcessBuilder/Basic.java fails on Alpine/musl
• 1a27164: 8287851: C2 crash: assert(t->meet(t0) == t) failed: Not monotonic
• 5b5bc6c: 8287672: jtreg test com/sun/jndi/ldap/LdapPoolTimeoutTest.java fails intermittently in nightly run
• dc4edd3: 8289183: jdk.jfr.consumer.RecordedThread.getId references Thread::getId, should be Thread::threadId
• c4dcce4: 8289619: JVMTI SelfSuspendDisablerTest.java failed with RuntimeException: Test FAILED: Unexpected thread state
• f5cdaba: 8245268: -Xcomp is missing from java launcher documentation
• ... and 7 more: https://git.openjdk.org/jdk19/compare/c20b3aa9c5ada4c87b3421fbc3290f4d6a4706ac...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.

[AlanBateman]

/integrate

[openjdk]

Going to push as commit b3a0e48.
Since your change was applied there have been 17 commits pushed to the master branch:

• 0b6fd48: 8288128: S390X: Fix crashes after JDK-8284161 (Virtual Threads)
• 30e134e: 8289091: move oop safety check from SharedRuntime::get_java_tid() to JavaThread::threadObj()
• 29ea642: 8287847: Fatal Error when suspending virtual thread after it has terminated
• f640fc5: 8067757: Incorrect HTML generation for copied javadoc with multiple @throws tags
• 0dff327: 8289569: [test] java/lang/ProcessBuilder/Basic.java fails on Alpine/musl
• 1a27164: 8287851: C2 crash: assert(t->meet(t0) == t) failed: Not monotonic
• 5b5bc6c: 8287672: jtreg test com/sun/jndi/ldap/LdapPoolTimeoutTest.java fails intermittently in nightly run
• dc4edd3: 8289183: jdk.jfr.consumer.RecordedThread.getId references Thread::getId, should be Thread::threadId
• c4dcce4: 8289619: JVMTI SelfSuspendDisablerTest.java failed with RuntimeException: Test FAILED: Unexpected thread state
• f5cdaba: 8245268: -Xcomp is missing from java launcher documentation
• ... and 7 more: https://git.openjdk.org/jdk19/compare/c20b3aa9c5ada4c87b3421fbc3290f4d6a4706ac...master

Your commit was automatically rebased without conflicts.

[openjdk]

@AlanBateman Pushed as commit b3a0e48.

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