Summary:
- port D64010 to dragonwell
- print the detail time when doing root processing in generational heap collection

Test Plan:
hotspot/test/gc/TestPrintGCRootsTraceTime.java
hotspot/test/gc/

Reviewers: 传胜

Differential Revision: https://aone.alibaba-inc.com/code/D851700

Summary:
- Port D65580 to dragonwell
- Print the young generation histogram once after parnew gc with the manageable flag: PrintYoungGenHistoAfterParNewGC

Test Plan: hotspot/test/gc/parNew/testPrintYoungGenHisto.sh

Reviewers: 传胜

Differential Revision: https://aone.alibaba-inc.com/code/D849729

Reviewed-by: kbarrett, brutisso
Contributed-by: jwha@google.com

8075210: Refactor strong root processing in order to allow G1 to evolve separately from GenCollectedHeap
Summary: Create a G1RootProcessor and move SharedHeap root processing to GenCollectedHeap
Reviewed-by: brutisso, tschatzl, ehelin

8075210: Refactor strong root processing in order to allow G1 to evolve separately from GenCollectedHeap
Summary: Create a G1RootProcessor and move SharedHeap root processing to GenCollectedHeap
Reviewed-by: brutisso, tschatzl, ehelin

Reviewed-by: brutisso, tschatzl

Summary: Removed all write barriers during reference processing and added explicit write barriers when iterating through the discovered list.
Reviewed-by: pliden, jmasa, tschatzl

Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com

8043029: Change 8037816 breaks HS build with older GCC versions which don't support diagnostic pragmas
8043164: Format warning in traceStream.hpp
Summary: Backport of main fix + two corrections, enables clang compilation, turns on format attributes, corrects/mutes warnings
Reviewed-by: kvn, coleenp, iveresov, twisti

Reviewed-by: tschatzl, mgerdin, jmasa

Reviewed-by: dholmes, kvn, stefank, twisti

Reviewed-by: jwilhelm, ehelin, tschatzl

Summary: Refactor the strong root processing to avoid using a boolean in addition to the ScanOption enum.
Reviewed-by: stefank, tschatzl, ehelin, jmasa

Reviewed-by: dholmes, egahlin

Summary: Enable CHECK_UNHANDLED_OOPS in fastdebug builds across all supported platforms.
Reviewed-by: coleenp, hseigel, dholmes, stefank, twisti, ihse, rdurbin
Contributed-by: lois.foltan@oracle.com

Reviewed-by: jmasa, ehelin

Reviewed-by: acorn, coleenp, sla
Contributed-by: NKaren Kinnear &lt;karen.kinnear@oracle.com&gt;, Bengt Rutisson &lt;bengt.rutisson@oracle.com&gt;, Calvin Cheung &lt;calvin.cheung@oracle.com&gt;, Erik Gahlin &lt;erik.gahlin@oracle.com&gt;, Erik Helin &lt;erik.helin@oracle.com&gt;, Jesper Wilhelmsson &lt;jesper.wilhelmsson@oracle.com&gt;, Keith McGuigan &lt;keith.mcguigan@oracle.com&gt;, Mattias Tobiasson &lt;mattias.tobiasson@oracle.com&gt;, Markus Gronlund &lt;markus.gronlund@oracle.com&gt;, Mikael Auno &lt;mikael.auno@oracle.com&gt;, Nils Eliasson &lt;nils.eliasson@oracle.com&gt;, Nils Loodin &lt;nils.loodin@oracle.com&gt;, Rickard Backman &lt;rickard.backman@oracle.com&gt;, Staffan Larsen &lt;staffan.larsen@oracle.com&gt;, Stefan Karlsson &lt;stefan.karlsson@oracle.com&gt;, Yekaterina Kantserova <yekaterina.kantserova@oracle.com>

Reviewed-by: ysr, johnc, jwilhelm

8005396: Use ParNew with only one thread instead of DefNew as default for CMS on single CPU machines
Reviewed-by: jmasa, jcoomes

Summary: Divide by zero error, if ParallelGCThreads is 0, when adjusting the PLAB size.
Reviewed-by: jmasa, jcoomes

Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: Njmasa &lt;jon.masamitsu@oracle.com&gt;, stefank &lt;stefan.karlsson@oracle.com&gt;, mgerdin &lt;mikael.gerdin@oracle.com&gt;, never <tom.rodriguez@oracle.com>

Summary: Employ PLABStats instances to record information about survivor and old PLABs, and use the recorded stats to adjust the sizes of survivor and old PLABS.
Reviewed-by: johnc, ysr
Contributed-by: NBrandon Mitchell <brandon@twitter.com>

7151532: DCmd for hotspot native memory tracking
Summary: Implementation of native memory tracking phase 1, which tracks VM native memory usage, and related DCmd
Reviewed-by: acorn, coleenp, fparain

Reviewed-by: mgerdin, johnc

Summary: Replace calls to os::javaTimeMillis() that are used to update the milliseconds since the last GC to an equivalent that uses a monotonically non-decreasing time source.
Reviewed-by: ysr, jmasa

Summary: Change variables representing the number of GC workers to uint from int and size_t.  Change the parameter in work(int i) to work(uint worker_id).
Reviewed-by: brutisso, tonyp

Summary: Select number of GC threads dynamically based on heap usage and number of Java threads
Reviewed-by: johnc, ysr, jcoomes

Summary: Use _max_num_q = max(discovery_degree, processing_degree), and let balance_queues() redistribute from discovery_degree to processing_degree of queues. This should also allow a more dynamic and flexible parallelism policy in the future.
Reviewed-by: jmasa, johnc

Summary: Age bits need not enter the mark-word preservation calculus; also affected, in addition to CMS, per CR synopsis above, were ParNew (but not DefNew), ParallelScavenge and G1, albeit to a lesser degree than CMS.
Reviewed-by: tonyp, johnc

Summary: Replaced MakeDeps and the includeDB files with more standardized solutions.
Reviewed-by: coleenp, kvn, kamg

Summary: Deprecated HandlePromotionFailure, removing the ability to turn off that feature, did away with one epoch look-ahead when deciding if a scavenge is likely to fail, relying on current data.
Reviewed-by: jmasa, johnc, poonam

6942771: SEGV in ParScanThreadState::take_from_overflow_stack
Reviewed-by: apetrusenko, ysr, pbk

Summary: Associate number of GC workers with the workgang as opposed to the task.
Reviewed-by: johnc, ysr

Reviewed-by: tonyp

Reviewed-by: ysr

Reviewed-by: tonyp, ysr

Summary: Change all the Sun copyrights to Oracle copyright
Reviewed-by: ohair

Summary: Ensure a full GC that clears SoftReferences before throwing an out-of-memory
Reviewed-by: ysr, jcoomes

Summary: Autonomic per-worker free block cache sizing, tunable coalition policies, fixes to per-size block statistics, retuned gain and bandwidth of some feedback loop filters to allow quicker reactivity to abrupt changes in ambient demand, and other heuristics to reduce fragmentation of the CMS old gen. Also tightened some assertions, including those related to locking.
Reviewed-by: jmasa

Summary: Make a special root-list for those few nmethods which might contain non-perm oops.
Reviewed-by: twisti, kvn, never, jmasa, ysr