RFR: 8336685: Shenandoah: Remove experimental incremental update mode [v2]

[Aleksey Shipilev]

On Wed, 24 Jul 2024 19:31:04 GMT, William Kemper <wkemper at openjdk.org> wrote:

>> We've reason to believe that this mode is very rarely used and its maintenance has become a burden for future development.
>> 
>> ## Testing
>> * hotspot_gc_shenandoah
>> * dacapo
>> * diluvian
>> * extremem
>> * hyperalloc
>> * specjbb2015
>> * specjvm2008
>
> William Kemper has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Remove unintentional new line

I like this. Consider another thing to clean up:

src/hotspot/share/gc/shenandoah/shenandoahConcurrentMark.cpp line 122:

> 120: 
> 121:       ShenandoahMarkRefsClosure<GENERATION> mark_cl(q, rp);
> 122:       ShenandoahSATBAndRemarkThreadsClosure tc(satb_mq_set, nullptr);

Looks like `ShenandoahSATBAndRemarkThreadsClosure` can be considerably simplified, now that we do not pass any closure to it.

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Marked as reviewed by shade (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/20316#pullrequestreview-2198733772
PR Review Comment: https://git.openjdk.org/jdk/pull/20316#discussion_r1691098698