RFR: 8350605: assert(!heap->is_uncommit_in_progress()) failed: Cannot uncommit bitmaps while resetting them [v3]

[William Kemper]

> The protocol which is meant to prevent regions from being uncommitted while their bitmaps are being reset may fail. This happens when the control thread attempts to wait for the uncommit thread to finish, but the uncommit thread has not yet indicated that it has started.
> 
> ## Testing
> GHA, Dacapo, Extremem, Heapothesys, Diluvian, SpecJBB2015, SpecJVM2008 (with and without stress flags, asserts). Also have run the JTREG test that failed this assertion over 10K times (and counting).

William Kemper has updated the pull request incrementally with one additional commit since the last revision:

  Comment tweak

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Changes:
  - all: https://git.openjdk.org/jdk/pull/23760/files
  - new: https://git.openjdk.org/jdk/pull/23760/files/b194db8f..1c32c0e3

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23760&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23760&range=01-02

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/23760.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23760/head:pull/23760

PR: https://git.openjdk.org/jdk/pull/23760