RFR: 8229012: When single stepping, the debug agent can cause the thread to remain in interpreter mode after single stepping completes [v2]

[Chris Plummer]

> When doing a  STEP_OVER, the debug agent does a NotifyFramePop() on the current frame as a safety net. After the STEP_OVER completes, the NotifyFramePop() is usually still in place. This keeps the thread in interp_only mode, which hurts performance. JVMTI has added a new ClearAllFramePops() API to allow clearing of the NotifyFramePop() and normal performance to resume.
> 
> Testing:
> 
> - [x] Tier1 CI
> - [x] Tier2 CI svc testing
> - [x] Tier3 CI svc testing
> - [x] Tier5 CI svc testing
> - [x] ran all svc test 10 times each on all supported platforms

Chris Plummer has updated the pull request incrementally with one additional commit since the last revision:

  Some minor cleanup.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/23182/files
  - new: https://git.openjdk.org/jdk/pull/23182/files/65ad54ad..2dc7a362

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23182&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23182&range=00-01

  Stats: 6 lines in 2 files changed: 0 ins; 1 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/23182.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23182/head:pull/23182

PR: https://git.openjdk.org/jdk/pull/23182