[jdk21u-dev] RFR: 8322846: Running with -Djdk.tracePinnedThreads set can hang

[Aleksey Shipilev]

Fixes the hang with the diagnostic option. 

Additional testing:
 - [x] New test fails without the fix, passes with it
 - [ ] Linux AArch64 server fastdebug, `all`

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Commit messages:
 - Backport faa9c6909dda635eb008b9dada6e06fca47c17d6

Changes: https://git.openjdk.org/jdk21u-dev/pull/270/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=270&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8322846
  Stats: 128 lines in 3 files changed: 100 ins; 12 del; 16 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/270.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/270/head:pull/270

PR: https://git.openjdk.org/jdk21u-dev/pull/270