RFR: 8334147: Shenandoah: Avoid taking lock for disabled free set logging [v4]

[William Kemper]

> Not clean. Backport to only take lock for logging when log level is enabled.

William Kemper has updated the pull request incrementally with two additional commits since the last revision:

 - Take lock when updating capacity and used for generational mode
 - 8341554: Shenandoah: Missing heap lock when updating usage for soft ref policy
   
   Reviewed-by: kdnilsen, ysr

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

Changes:
  - all: https://git.openjdk.org/shenandoah-jdk21u/pull/113/files
  - new: https://git.openjdk.org/shenandoah-jdk21u/pull/113/files/275e76d9..36af3a6f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=shenandoah-jdk21u&pr=113&range=03
 - incr: https://webrevs.openjdk.org/?repo=shenandoah-jdk21u&pr=113&range=02-03

  Stats: 14 lines in 2 files changed: 6 ins; 0 del; 8 mod
  Patch: https://git.openjdk.org/shenandoah-jdk21u/pull/113.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah-jdk21u.git pull/113/head:pull/113

PR: https://git.openjdk.org/shenandoah-jdk21u/pull/113