RFR: 8341630: G1: Adopt PartialArrayState to consolidate marking stack in concurrent marking

[Thomas Schatzl]

On Thu, 15 Jan 2026 10:23:40 GMT, Ivan Walulya <iwalulya at openjdk.org> wrote:

> Hi,
> 
> Please review this change which adopts the `PartialArrayState` mechanism for G1 concurrent marking.
> 
> The `PartialArrayState` mechanism can push multiple continuations to the task queues, so it also solves the single-continuation limitation issue in [JDK-8167480](https://bugs.openjdk.org/browse/JDK-8167480).
> 
> Testing: Mach5 Tier 1-3.

lgtm.

src/hotspot/share/gc/g1/g1ConcurrentMark.cpp line 679:

> 677: }
> 678: #endif
> 679: 

Extra newline.

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Marked as reviewed by tschatzl (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/29249#pullrequestreview-3670387477
PR Review Comment: https://git.openjdk.org/jdk/pull/29249#discussion_r2698117149