RFR: 8369622: GlobalChunkPoolMutex is recursively locked during error handling [v2]

[David Holmes]

On Tue, 21 Oct 2025 13:52:14 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

>> This change disables recursive locking for the ChunkPoolLocker during error handling for NMT callers.  The patch is written by Johan as an alternative to supporting another recursive locker for this lock.
>> Tested with tier1-4, tier5 on aarch64 (product and debug).
>
> Coleen Phillimore has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Add assert, fix access modifiers and add Afshin's test.

A couple of nitty suggestions but nothing essential.

src/hotspot/share/memory/arena.cpp line 53:

> 51:     _locked = true;
> 52:   } else {
> 53:     precond(ls == LockStrategy::Try);

Nit: this isn't really a "precond", it is just an assert.

src/hotspot/share/memory/arena.hpp line 44:

> 42:   enum class LockStrategy { Lock, Try };
> 43:  private:
> 44:   bool _locked;

Nit: if you place this first you can save one of the "public"s.

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

Marked as reviewed by dholmes (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/27869#pullrequestreview-3364108739
PR Review Comment: https://git.openjdk.org/jdk/pull/27869#discussion_r2450751142
PR Review Comment: https://git.openjdk.org/jdk/pull/27869#discussion_r2450753191