RFR: 8298276: JFR: Update NMT events to make use of common periodic timestamp feature [v2]

[Erik Gahlin]

> Could I have review of a change that ensures NMT events use the same timestamp.
> 
> Testing: tier1, tier2, jdk/jdk/jfr/*
> 
> Thanks
> Erik

Erik Gahlin has updated the pull request incrementally with one additional commit since the last revision:

  Make get_usage static

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/12564/files
  - new: https://git.openjdk.org/jdk/pull/12564/files/387c8087..8256a8e5

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12564&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12564&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/12564.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12564/head:pull/12564

PR: https://git.openjdk.org/jdk/pull/12564