RFR: 8273915: Create 'nosafepoint' rank [v3]

[Ioi Lam]

On Mon, 20 Sep 2021 20:16:03 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

>> Partition safepoint checking and nonchecking lock ranks. The nonchecking locks are always lower ranked than the safepoint checking locks because they cannot block.
>> 
>> This moves some leaf locks to 'nosafepoint' rank and corrects relative ranking.
>> 
>> Tested with tier1-6 and built and run tier1 tests with shenandoah locally.
>
> Coleen Phillimore has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Add comment and change enum name to Rank.

LGTM

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Marked as reviewed by iklam (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/5550