RFR: 8291714: Implement a Multi-Reader Single-Writer mutex for Hotspot [v5]

[Johan Sjölén]

On Tue, 30 Aug 2022 00:13:35 GMT, David Holmes <dholmes at openjdk.org> wrote:

>To be clear, you will only ever get a null if someone passes it in explicitly as Thread::current_or_null() should never be able to return null in the contexts you would use this RWL.

Context: UL uses static initialization for LogTagSets, these use the RWLock and as such our thread system isn't initialized yet. It's not strictly necessary, as we can re-write things to not require this.

Edit: Perhaps the right decision is to simply delay the initialization of LogTagSets.

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

PR: https://git.openjdk.org/jdk/pull/9838