RFR: 8256265: G1: Improve parallelism in regions that failed evacuation [v5]

[Thomas Schatzl]

On Tue, 13 Sep 2022 16:00:05 GMT, Thomas Schatzl <tschatzl at openjdk.org> wrote:

>> Hi all,
>> 
>>   can I have reviews on this change that makes the evacuation failure remove forwards phase split the work across threads within regions?
>> 
>> This work is a continuation of PR#7047 from @Hamlin-Li and latest improvements from @albertnetymk in that thread. This is reflected in the first commit, I added a fair amount of changes to fix bugs and streamline the code.  
>> 
>> Testing: tier1-8 with G1EvacuationFailureALot enabled, tier1-5 as is
>
> Thomas Schatzl has updated the pull request incrementally with two additional commits since the last revision:
> 
>  - clear_bitmap_for_region() -> clear_mark_data_for_region()
>  - ayang review 3

The last commit prospectively renames `clear_bitmap_for_region()`.

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

PR: https://git.openjdk.org/jdk/pull/9980