[jdk17u-dev] RFR: 8305403: Shenandoah evacuation workers may deadlock

[William Kemper]

This is a backport of https://github.com/openjdk/jdk/pull/13309. It was not clean, but the conflict was trivial to resolve.

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Commit messages:
 - Backport 793da60ee833d09db0f6f14b50a7cbd7f4549e3b

Changes: https://git.openjdk.org/jdk17u-dev/pull/1242/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1242&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305403
  Stats: 39 lines in 6 files changed: 1 ins; 33 del; 5 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1242.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1242/head:pull/1242

PR: https://git.openjdk.org/jdk17u-dev/pull/1242