RFR: 8369913: Parallel: Refactor PSAdjustTask

Wed Oct 15 13:39:30 UTC 2025

Cleanup roots processing (adjusting/remapping) during the adjust-phase of full-gc, so that relevant roots are grouped together with some documentations. Also, the use of `SubTasksDone` is replaced with a `volatile bool`, which is more transparent in the context.

Test: tier1-5

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Commit messages:
 - pgc-adjust-root

Changes: https://git.openjdk.org/jdk/pull/27822/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27822&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8369913
  Stats: 41 lines in 1 file changed: 20 ins; 14 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/27822.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27822/head:pull/27822

PR: https://git.openjdk.org/jdk/pull/27822