hg: jdk8u/jdk8u-dev/jdk: 8202788: Explicitly reclaim cached thread-local direct buffers at thread exit

[zgu at redhat.com]

Changeset: 5977420ebb51
Author:    plevart
Date:      2018-06-22 17:56 +0200
URL:       https://hg.openjdk.java.net/jdk8u/jdk8u-dev/jdk/rev/5977420ebb51

8202788: Explicitly reclaim cached thread-local direct buffers at thread exit
Summary: Add internal TerminatingThreadLocal and use it to free cached thread-local direct buffers and nio-fs native buffers
Reviewed-by: tonyp, alanb

! src/share/classes/java/lang/Thread.java
! src/share/classes/java/lang/ThreadLocal.java
+ src/share/classes/jdk/internal/misc/TerminatingThreadLocal.java
! src/share/classes/sun/nio/ch/Util.java
! src/share/classes/sun/nio/fs/NativeBuffers.java
+ test/java/nio/channels/FileChannel/TempDirectBuffersReclamation.java
+ test/jdk/internal/misc/TerminatingThreadLocal/TestTerminatingThreadLocal.java
! test/sun/nio/ch/TestMaxCachedBufferSize.java