8316229: Enhance class initialization logging

[dholmes-ora]

This change adds some additional debug logging to the class linking and initialization process. It was useful in diagnosing the deadlock described by:

https://bugs.openjdk.org/browse/JDK-8316469

See the example output in JBS issue.

The changes are mostly uncontroversial but I needed to expose a way to access the init thread's name, which can't use the regular name() method as the safety check doesn't recognise the calling context as being safe.

Testing:

• manual examination of logging output
• ran the only test that enables class+init logging: runtime/logging/ClassInitializationTest.java (no change as expected)
• tiers1-3 sanity

Thanks.

---

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-8316229: Enhance class initialization logging (Enhancement - P4)

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer)
• Coleen Phillimore (@coleenp - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/15809/head:pull/15809
$ git checkout pull/15809

Update a local copy of the PR:
$ git checkout pull/15809
$ git pull https://git.openjdk.org/jdk.git pull/15809/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 15809

View PR using the GUI difftool:
$ git pr show -t 15809

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/15809.diff

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[mlbridge]

Webrevs

• 01: Full - Incremental (d7530af0)
• 00: Full (8db375eb)

[shipilev]

This looks good, I have only stylistic questions/suggestions.

[dholmes-ora]

Thanks for looking at this @shipilev !

[openjdk]

@dholmes-ora 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:

8316229: Enhance class initialization logging

Reviewed-by: shade, coleenp

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 97 new commits pushed to the master branch:

• 242eeae: 8286757: adlc tries to build with /pathmap but without /experimental:deterministic
• b275bdd: 8308995: Update Network IO JFR events to be static mirror events
• e1870d3: 8316411: compiler/compilercontrol/TestConflictInlineCommands.java fails intermittent with force inline by CompileCommand missing
• ec74194: 8316546: Backout JDK-8315932: runtime/InvocationTests spend a lot of time on dependency verification
• 2568188: 8316547: Use JUnit.dir jtreg property with jpackage JUnit tests
• 833a828: 8315876: Open source several Swing CSS related tests
• 7ce5bd1: 8316468: os::write incorrectly handles partial write
• d19e017: 8315951: Open source several Swing HTMLEditorKit related tests
• 62c0a1b: 8315883: Open source several Swing JToolbar tests
• 0c97246: 8311113: Remove invalid pointer cast and clean up setLabel() in awt_MenuItem.cpp
• ... and 87 more: https://git.openjdk.org/jdk/compare/23fab1181b6a053efc4661d5a10caa90b109aa06...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.

[coleenp]

This looks reasonable. I like the variable for log_is_enabled, keeps it from being less intrusive.
Edit: too intrusive.

[dholmes-ora]

Thanks for the reviews @shipilev and @coleenp !

/integrate

[openjdk]

Going to push as commit 8412479.
Since your change was applied there have been 108 commits pushed to the master branch:

• c04c9ea: 8316627: JViewport Test headless failure
• 5cacf21: 8316156: ByteArrayInputStream.transferTo causes MaxDirectMemorySize overflow
• 3461c7b: 8316532: Native library copying in BuildMicrobenchmark.gmk cause dups on macOS
• 3301fb1: 8315869: UseHeavyMonitors not used
• 54028e7: 8316562: serviceability/sa/jmap-hprof/JMapHProfLargeHeapTest.java times out after JDK-8314829
• 7c991cc: 8296246: Update Unicode Data Files to Version 15.1.0
• a021dbc: 8316149: Open source several Swing JTree JViewport KeyboardManager tests
• 455cfae: 8315880: change LockingMode default from LM_LEGACY to LM_LIGHTWEIGHT
• 9e00949: 8316427: Duplicated code for {obj,type}ArrayKlass::array_klass
• c43ebd3: 8315981: Opensource five more random Swing tests
• ... and 98 more: https://git.openjdk.org/jdk/compare/23fab1181b6a053efc4661d5a10caa90b109aa06...master

Your commit was automatically rebased without conflicts.

[openjdk]

@dholmes-ora Pushed as commit 8412479.

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