RFR: 8229517: Support for optional asynchronous/buffered logging [v8]

[Xin Liu]

> This patch provides a buffer to store asynchrounous messages and flush them to
> underlying files periodically.

Xin Liu has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 18 additional commits since the last revision:

 - Refactor LogAsyncFlusher::abort()
   
   This change makes sure LogAsyncFlusher::abort() is lock-less.
   Therefore, it's not subject to mutex rank issue. Newly added
   gtest(mutex_lock_access_leaf)  may deliberately trigger SIGSEGV
   while holding access rank mutex, so abort() must be lockless.
 - Merge branch 'master' into JDK-8229517
 - Fix a race condition bug on LogAsyncFlusher termination.
   
   I saw intermitent crashes of java with the following arguments.
   -Xlog:'all=trace:file=hotspot-x.log:level,tags:filecount=0,async=true' --version
   
   The root cause is that there is a race condition between main thread _exit and
   LogAsyncFlusher::run. This patch added a synchronization using
   Terminator_lock in LogAsyncFlusher::terminate. This guranatees that no
   log entry will emit when main thread is exiting.
 - Resolve rank conflict between tty_lock and LogAsyncFlusher's _lock.
   
   LogAsyncFlusher::_lock ranks Mutex::tty on purpose, which is same as tty_lock.
   Ideally, they are orthogonal. In reality, it's possible that a thread emits logs
   to a log file while (mistakenly) holding tty_lock. ttyUnlocker is placed in enqueue
   member functions to resolve conflicts betwen them.
   
   This patch fixed the jtreg test: runtime/logging/RedefineClasses.java and the
   full brunt logging -Xlog:'all:file=hotspot.log::async=true'
 - Remove LogAsyncInterval completely
   
   It was used as a timeout parameter of the monitor. Now the monitor is waked up
   when the occupancy of asynclog buffer is more 3/4.
 - Support Jcmd pid VM.log disable
   
   This patch also supports to add a new output dynamically. If
   output_option specifies async=true, the new output will use
   asynchronous writing.
   
   Currently jcmd VM.log prohibts users from changing established
   output_options in runtime. users can disable them all and then
   recreate them with the new output_options.
 - Fix build issue with `--disable-precompiled-headers`
 - Inject the number of dropped messages since last dumpping.
   
   Each LogOutput has an independent counter. The out-of-band message
   "[number] messages dropped..." will be dumped into its corresponding
   LogOutput.
 - Revert "fix runtime/logging/RedefineClasses.java crashed with -XX:+AsyncLogging"
   
   This reverts commit 81b2a0cb2a6cf57b1cd0baacdf8c0419f14819b4.
   
   This problem is sidetracked by JDK-8265102.
 - fix runtime/logging/RedefineClasses.java crashed with -XX:+AsyncLogging
   
   nmethod::print(outputStream* st) should not obtain tty_lock by assuming
   st is defaultStream. It could be logStream as well.
   
   Currently, AyncLogFlusher::_lock has the same rank of tty_lock.
   https://issues.amazon.com/issues/JVM-563
 - ... and 8 more: https://git.openjdk.java.net/jdk/compare/5e87deb4...4cf4a57f

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/3135/files
  - new: https://git.openjdk.java.net/jdk/pull/3135/files/2bd104ff..4cf4a57f

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3135&range=07
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3135&range=06-07

  Stats: 124746 lines in 3715 files changed: 70137 ins; 41702 del; 12907 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3135.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3135/head:pull/3135

PR: https://git.openjdk.java.net/jdk/pull/3135