RFR: 8337511: Implement JEP 404: Generational Shenandoah (Experimental) [v8]

[William Kemper]

On Thu, 21 Nov 2024 09:14:57 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

>> William Kemper has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 524 commits:
>> 
>>  - Merge remote-tracking branch 'shenandoah/master' into great-genshen-pr-redux
>>  - 8344670: GenShen: Use concurrent worker session for concurrent mark phase
>>    
>>    Reviewed-by: kdnilsen
>>  - 8344640: GenShen: Reuse existing card mark barrier function when dropping references
>>    
>>    Reviewed-by: shade, ysr
>>  - 8344592: GenShen: Remove unnecessary comments and changes
>>    
>>    Reviewed-by: kdnilsen
>>  - 8344263: GenShen: Reduce extraneous log messages at INFO level
>>    
>>    Reviewed-by: ysr, shade
>>  - 8344638: GenShen: Verifier should not touch claim token
>>    
>>    Reviewed-by: shade
>>  - Merge
>>  - 8344320: GenShen: Possible null pointer usage in shGenerationalHeap
>>    
>>    Reviewed-by: wkemper, ysr
>>  - 8344321: GenShen: Fix various sonar scan warnings
>>    
>>    Reviewed-by: kdnilsen, shade
>>  - 8344264: GenShen: Improve comments and method names
>>    
>>    Reviewed-by: shade
>>  - ... and 514 more: https://git.openjdk.org/jdk/compare/95a00f8a...7ab16403
>
> src/hotspot/share/gc/shenandoah/shenandoahHeap.hpp line 134:
> 
>> 132:   bool is_thread_safe() override { return true; }
>> 133: };
>> 134: 
> 
> This looks like belonging in one of the `*closures.hpp` header.

https://bugs.openjdk.org/browse/JDK-8344779

> src/hotspot/share/gc/shenandoah/shenandoahHeap.hpp line 754:
> 
>> 752:   oop try_evacuate_object(oop src, Thread* thread, ShenandoahHeapRegion* from_region, ShenandoahAffiliation target_gen);
>> 753: public:
>> 754: 
> 
> I think this new line should be before `public:`

Sneaking this into: https://bugs.openjdk.org/browse/JDK-8344779

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/21273#discussion_r1852709552
PR Review Comment: https://git.openjdk.org/jdk/pull/21273#discussion_r1852711083