RFR: 8365190: Remove LockingMode related code from share

[Fredrik Bredberg]

On Thu, 4 Sep 2025 02:18:38 GMT, David Holmes <dholmes at openjdk.org> wrote:

>> Since the integration of [JDK-8359437](https://bugs.openjdk.org/browse/JDK-8359437) the `LockingMode` flag can no longer be set by the user. After that, a number of PRs has been integrated which has removed all `LockingMode` related code from all platforms (except from zero, which is done in this PR).
>> 
>> This PR removes `LockingMode` related code from the shared (non-platform specific) files. It also removes the `LockingMode` variable itself.
>> 
>> Passes tier1-tier5 with no added problems.
>
> src/hotspot/share/runtime/basicLock.hpp line 53:
> 
>> 51:   static int displaced_header_offset_in_bytes() { return metadata_offset_in_bytes(); }
>> 52: 
>> 53:   // For lightweight locking
> 
> If the following are for lightweight locking then what are the two previous for?

For something old and soon forgotten. :)
After I had integrated some platforms I realized that this was no longer needed, but since I want to keep this PR clean of platform changes, I have added this to the [next cleanup](https://bugs.openjdk.org/browse/JDK-8365191).

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PR Review Comment: https://git.openjdk.org/jdk/pull/27041#discussion_r2321540639