[jdk21u] RFR: 8316337: (bf) Concurrency issue in DirectByteBuffer.Deallocator

Fri Oct 6 18:57:30 UTC 2023

Clean backport to improve safety. Records are available in JDK 21, so the whole thing works.

Additional testing:
  - [x] macos-aarch64-server-fastdebug, `java/nio`

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Commit messages:
 - Backport cf74b8c2a32f33019a13ce80b6667da502cc6722

Changes: https://git.openjdk.org/jdk21u/pull/231/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=231&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8316337
  Stats: 53 lines in 3 files changed: 5 ins; 19 del; 29 mod
  Patch: https://git.openjdk.org/jdk21u/pull/231.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/231/head:pull/231

PR: https://git.openjdk.org/jdk21u/pull/231