[jdk21u-dev] RFR: 8331405: Shenandoah: Optimize ShenandoahLock with TTAS

[Xiaolong Peng]

Hi all,

This pull request contains a backport of commit [c4fe5bf9](https://github.com/openjdk/jdk/commit/c4fe5bf90c2d368c29714de63a90eca444fb3ece) from the [openjdk/jdk](https://git.openjdk.org/jdk) repository, is is preparation of next backport for https://bugs.openjdk.org/browse/JDK-8331411.

The commit being backported was authored by Aleksey Shipilev on 2 May 2024 and was reviewed by Zhengyu Gu and Y. Srinivas Ramakrishna.


Additional tests:
- [x] `make clean test CONF=macosx-aarch64-server-fastdebug TEST=hotspot_gc_shenandoah`:

Test summary
==============================
   TEST                                              TOTAL  PASS  FAIL ERROR   
   jtreg:test/hotspot/jtreg:hotspot_gc_shenandoah      261   261     0     0   
==============================
TEST SUCCESS



Thanks!

-------------

Commit messages:
 - Backport c4fe5bf90c2d368c29714de63a90eca444fb3ece

Changes: https://git.openjdk.org/jdk21u-dev/pull/842/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=842&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8331405
  Stats: 2 lines in 1 file changed: 1 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/842.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/842/head:pull/842

PR: https://git.openjdk.org/jdk21u-dev/pull/842