RFR: 8314629: Generational ZGC: Clearing All SoftReferences log line lacks GCId

[Guoxiong Li]

Hi all,

This patch adds the GCId to the log of soft reference policy. I move the related code to the start of the old generational GC which needs  to add a parameter `ZDriverRequest` in the method `ZDriverMajor::collect_old`. An alternative, which doesn't need to add a parameter, is only moving the related code to the start of the major GC, concretely the method `ZDriverMajor::gc`. But considering the references only be cleared in old generational GC, I make such decision. Waiting for your opinion on it.

Thanks for taking the time to review.

Best Regards,
-- Guoxiong

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Commit messages:
 - JDK-8314629: Generational ZGC: Clearing All SoftReferences log line lacks GCId

Changes: https://git.openjdk.org/jdk/pull/17196/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17196&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8314629
  Stats: 13 lines in 2 files changed: 5 ins; 4 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/17196.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17196/head:pull/17196

PR: https://git.openjdk.org/jdk/pull/17196