RFR: 8369622: GlobalChunkPoolMutex needs to be recursive

[David Holmes]

On Mon, 13 Oct 2025 18:14:56 GMT, Zhengyu Gu <zgu at openjdk.org> wrote:

>> src/hotspot/share/memory/arena.cpp line 55:
>> 
>>> 53:       PlatformMutex::lock();
>>> 54:       _owner = t;
>>> 55:     }
>> 
>> As per the comment:
>> 
>> // For many calls, the current thread has not
>> // been created so we cannot use Mutex.
>> 
>> this ownership test won't allow for recursive use in those circumstances. So we have slightly odd semantics here that the mutex is recursive for attached threads but not for un-attached. For this specialised usecase maybe we can tolerate that.
>
> I don't see how it can work without recursion count ...

Doh! Yep Zhengyu is right.

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PR Review Comment: https://git.openjdk.org/jdk/pull/27759#discussion_r2427927714