RFR: 8351655: Optimize ObjectMonitor::unlink_after_acquire() [v3]

[Fredrik Bredberg]

On Fri, 21 Mar 2025 09:23:35 GMT, Fredrik Bredberg <fbredberg at openjdk.org> wrote:

>> This PR implements an optimization of `ObjectMonitor::unlink_after_acquire()`. If it's possible it only converts the first part (the singly linked part) of the `entry_list` into a doubly linked list and leave the _entry_list_tail pointer untouched. 
>> 
>> It has passed tier1-tier8 tests.
>
> Fredrik Bredberg has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Second update after review

Thanks for the reviews. I'll integrate after the weekend.

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PR Comment: https://git.openjdk.org/jdk/pull/24078#issuecomment-2743561750