RFR: 8283520: JFR: Memory leak in dcmd_arena [v2]

[Markus Grönlund]

> Greetings,
> 
> This changeset will address the memory leak in the dcmd_arena.
> 
> Testing: jdk_jfr
> 
> Thanks to @shipilev for reporting this issue.
> 
> Thanks
> Markus

Markus Grönlund has updated the pull request incrementally with one additional commit since the last revision:

  hw thread is one-to-many javathreads

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8727/files
  - new: https://git.openjdk.java.net/jdk/pull/8727/files/0b233f39..c7a34d5d

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8727&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8727&range=00-01

  Stats: 5 lines in 1 file changed: 0 ins; 2 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8727.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8727/head:pull/8727

PR: https://git.openjdk.java.net/jdk/pull/8727