RFR: 8262910: Cleanup THREAD/TRAPS/naming and typing issues in ObjectMonitor and related code [v4]

[Daniel D.Daugherty]

On Fri, 5 Mar 2021 04:59:02 GMT, David Holmes <dholmes at openjdk.org> wrote:

>> ObjectMonitors can only be used by JavaThreads (modulo some interactions with hashcodes and deflation) but we use "Thread*" almost everywhere mainly due to use of TRAPS (and TRAPS will itself use JavaThread once JDK-8252685 is done). Also some uses of TRAPS in the API's are wrong as, for example, monitor entry can never throw an exception.
>> 
>> So this cleanup tackles:
>> - remove incorrect use of TRAPS
>> - change "Thread*" to "JavaThread*" where applicable
>> - don't use THREAD for things not related to exception processing
>> - standardise the naming so that we have "JavaThread* current" rather a mix if Self/THREAD/jt etc.
>> - remove unnecessary as_Java_thread() conversions
>> - other misc cleanup I noticed in some functions
>> 
>> The cleanup is predominantly in objectMonitor.* and synchronizer.* but with a fan out to the users of those APIs. No attempt is made to cleanup the callers beyond ensuring we have a suitable JavaThread reference for the calls. 
>> 
>> Thanks,
>> David
>
> David Holmes has updated the pull request incrementally with three additional commits since the last revision:
> 
>  - Fix typo
>  - Fixed up BiasedLocking code in ObjectSynchronizer::enter
>  - iFixed alignment in macro

Thumbs up.

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Marked as reviewed by dcubed (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/2802