8257151: ZGC: Simplify ZVerify

[stefank]

ZVerify has a few oddities:

1. The comment and the parameter name don't match.

void ZVerify::before_zoperation() {
  // Verify strong roots
  ZStatTimerDisable disable;
  roots(false /* verify_strong */, false /* verify_weaks */);
}

This is caused by a name clash between the layers:

roots_strong(bool verify_fixed
roots(bool verify_strong
roots_and_objects(bool verify_strong

2. Both usages of roots_and_objects pass true as the verify_strong argument:

void ZVerify::after_mark() {
  // Verify all strong roots and strong references
  ZStatTimerDisable disable;
  roots_and_objects(true /* verify_strong */, false /* verify_weaks */);
}

void ZVerify::after_weak_processing() {
  // Verify all roots and all references
  ZStatTimerDisable disable;
  roots_and_objects(true /* verify_strong */, true /* verify_weaks */);
}

The proposal is to remove the middle layers and be more explicit at the call sites.

---

Progress

• Change must not contain extraneous whitespace
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• Change must be properly reviewed

Testing

	Linux x64	Linux x86	Windows x64	macOS x64
Build	⏳ (2/2 running)	⏳ (2/2 running)	⏳ (2/2 running)	⏳ (2/2 running)

Issue

• JDK-8257151: ZGC: Simplify ZVerify

Reviewers

• Per Liden (@pliden - Reviewer)
• Erik Österlund (@fisk - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/1449/head:pull/1449
$ git checkout pull/1449

[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 The following label will be automatically applied to this pull request:

• hotspot-gc

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[mlbridge]

Webrevs

• 00: Full (2d12b14)

[pliden]

Looks good.

[openjdk]

@stefank 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:

8257151: ZGC: Simplify ZVerify

Reviewed-by: pliden, eosterlund

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 5 new commits pushed to the master branch:

• bf66d73: 8257073: ZGC: Try forward object before retaining page
• 1b3aa3a: 8256831: MIPS Zero builds fail with undefined __atomic_compare_exchange_8
• 734d3c3: 8256862: Several java/foreign tests fail on x86_32 platforms
• 7946c94: 8257082: ZGC: Clean up ZRuntimeWorkers and ZWorkers
• f6d6a07: 8256938: Improve remembered set sampling task scheduling

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
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.

[fisk]

Looks good.

[stefank]

Thanks for reviewing!
/integrate

[openjdk]

@stefank Since your change was applied there have been 5 commits pushed to the master branch:

• bf66d73: 8257073: ZGC: Try forward object before retaining page
• 1b3aa3a: 8256831: MIPS Zero builds fail with undefined __atomic_compare_exchange_8
• 734d3c3: 8256862: Several java/foreign tests fail on x86_32 platforms
• 7946c94: 8257082: ZGC: Clean up ZRuntimeWorkers and ZWorkers
• f6d6a07: 8256938: Improve remembered set sampling task scheduling

Your commit was automatically rebased without conflicts.

Pushed as commit 0a5de50.

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