RFR: 8286893: G1: Recent card set coarsening statistics wrong [v4]

[tqxia]

> Looking at G1CardSet::print_coarsen_stats() the recent coarsening stats are calculated by:
> 
> current total coarsening - coarsening happened in previous (the one before the latest) GC cycle
> 
> but should be
> 
> current total coarsening - previous total coarsening
> 
> 
> 
> A sample output after the commit:
> GC(71) Coarsening (recent): Inline->AoC 62300 (202) AoC->Howl 6879 (163) Howl->Full 0 (0) Inline->AoC 52757 (123) AoC->BitMap 3750 (498) BitMap->Full 0 (0)
> GC(71) Coarsening (all): Inline->AoC 7032200 (8895) AoC->Howl 2167925 (13809) Howl->Full 0 (0) Inline->AoC 16892632 (11060) AoC->BitMap 300358 (32143) BitMap->Full 0 (0)
> GC(72) Coarsening (recent): Inline->AoC 61664 (87) AoC->Howl 6430 (70) Howl->Full 0 (0) Inline->AoC 49677 (30) AoC->BitMap 3358 (179) BitMap->Full 0 (0)
> GC(72) Coarsening (all): Inline->AoC 7093864 (8982) AoC->Howl 2174355 (13879) Howl->Full 0 (0) Inline->AoC 16942309 (11090) AoC->BitMap 303716 (32322) BitMap->Full 0 (0)
> GC(74) Coarsening (recent): Inline->AoC 807201 (57) AoC->Howl 13360 (48) Howl->Full 0 (0) Inline->AoC 94560 (30) AoC->BitMap 29545 (190) BitMap->Full 0 (0)
> GC(74) Coarsening (all): Inline->AoC 7901065 (9039) AoC->Howl 2187715 (13927) Howl->Full 0 (0) Inline->AoC 17036869 (11120) AoC->BitMap 333261 (32512) BitMap->Full 0 (0)
> GC(75) Coarsening (recent): Inline->AoC 137571 (258) AoC->Howl 70042 (659) Howl->Full 0 (0) Inline->AoC 543734 (461) AoC->BitMap 5747 (937) BitMap->Full 0 (0)
> GC(75) Coarsening (all): Inline->AoC 8038636 (9297) AoC->Howl 2257757 (14586) Howl->Full 0 (0) Inline->AoC 17580603 (11581) AoC->BitMap 339008 (33449) BitMap->Full 0 (0)
> 
> 
> 
> Testing: tier1

tqxia has refreshed the contents of this pull request, and previous commits have been removed. The incremental views will show differences compared to the previous content of the PR. The pull request contains one new commit since the last revision:

  8286893: G1: Recent card set coarsening statistics wrong

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8785/files
  - new: https://git.openjdk.java.net/jdk/pull/8785/files/c61b2c8d..2c8bb0aa

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8785&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8785&range=02-03

  Stats: 3 lines in 2 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8785.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8785/head:pull/8785

PR: https://git.openjdk.java.net/jdk/pull/8785