RFR: 8315462: [REDO] runtime/NMT/SummarySanityCheck.java failed with "Total committed (MMMMMM) did not match the summarized committed (NNNNNN)" [v3]

[Afshin Zafari]

> When taking snapshot of malloc entries, other threads may update the items that already copied so change their corresponding sum/count. To make the sum/count values be consistent with whatever copied, they are calculated during copy and then set explicitly if any mismatch detected.
> The function body is also moved to cpp file.  
> 
> ### Tests
> mach5 tiers 1-5 all platforms.

Afshin Zafari has updated the pull request incrementally with three additional commits since the last revision:

 - Merge branch '_8315462'
 - merge master
 - comments applied.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/16237/files
  - new: https://git.openjdk.org/jdk/pull/16237/files/a1014001..354c6ca5

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=16237&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16237&range=01-02

  Stats: 9304 lines in 370 files changed: 1220 ins; 6641 del; 1443 mod
  Patch: https://git.openjdk.org/jdk/pull/16237.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16237/head:pull/16237

PR: https://git.openjdk.org/jdk/pull/16237