8289538: Make G1BlockOffsetTablePart unaware of block sizes

[tschatzl]

Hi all,

can I have reviews for this change that makes G1BlockOffsetTablePart unaware of block sizes: as discussed in PR#9059/JDK-8287555 this is a good idea to make G1BlockOffsetTablePart just for "dumb" retrieval of the BOT entries, which makes the code simpler, avoiding some calling back and forth between HeapRegion and G1BlockOffsetTablePart.

There is still the wart that G1BlockOffsetTablePart::verify() needs block_size, but since it's just verification I think this is fine. An alternative suggested by @albertnetymk is to remove that method completely.

Testing: local compilation, gha, some benchmark checking that card scans/ms does not degrade

Thanks,
Thomas

---

Progress

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Issue

• JDK-8289538: Make G1BlockOffsetTablePart unaware of block sizes

Reviewers

• Albert Mingkun Yang (@albertnetymk - Reviewer) ⚠️ Review applies to 9e847fc0
• Ivan Walulya (@walulyai - Reviewer) ⚠️ Review applies to 5eddae0a

Reviewing

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Webrevs

• 04: Full - Incremental (b8595efc)
• 03: Full (d98eb3ae)
• 02: Full - Incremental (5eddae0a)
• 01: Full - Incremental (9e847fc0)
• 00: Full (c43b00e8)

[albertnetymk]

Just some minor & subjective comment.

[openjdk]

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

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8289538: Make G1BlockOffsetTablePart unaware of block sizes

Reviewed-by: ayang, iwalulya

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[walulyai]

Lgtm!

[tschatzl]

Thanks @walulyai @albertnetymk for your reviews.

/integrate

[openjdk]

Going to push as commit f7b1830.
Since your change was applied there have been 2 commits pushed to the master branch:

• 5564eff: 8289763: Remove NULL check in CDSProtectionDomain::init_security_info()
• a694e9e: 8288838: jpackage: file association additional arguments

Your commit was automatically rebased without conflicts.

[openjdk]

@tschatzl Pushed as commit f7b1830.

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