RFR: 8334904: Add some perf counters to monitor the usage of VM locks [v2]

[Calvin Cheung]

> Adding a few perf counters to monitor the usage of VM locks. The counters include hold time, wait time, and number of events. They can be enabled via `-Xlog:pref+vmlocks`.
> 
> Please refer to the [comment](https://bugs.openjdk.org/browse/JDK-8334904?focusedId=14684322&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14684322) in the bug report for an example output.
> 
> Passed tiers 1 - 4 testing.

Calvin Cheung has updated the pull request incrementally with one additional commit since the last revision:

  @dholmes-ora comments

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Changes:
  - all: https://git.openjdk.org/jdk/pull/19954/files
  - new: https://git.openjdk.org/jdk/pull/19954/files/c5488ab2..fc98e45c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19954&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19954&range=00-01

  Stats: 40 lines in 6 files changed: 9 ins; 5 del; 26 mod
  Patch: https://git.openjdk.org/jdk/pull/19954.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19954/head:pull/19954

PR: https://git.openjdk.org/jdk/pull/19954