Request for review: 8006757: Refactor Socket and File I/O tracing

[Claes Redestad]

Hi all,

  this is a refactoring of the I/O trace instrumentation that's going into JDK
7u14. The fix is only applicable to jdk7 since the corresponding code does not yet
exist in jdk8.

Bug: 8006757: Refactor Socket and File I/O tracing
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8006757

Description: By moving all parameters to the xxEnd-methods in IoTrace, we can defer
evaluation/object allocations until we know events will be written, which may reduce
the overhead of enabling these events.

Webrev:
http://cr.openjdk.java.net/~sla/clredest/8006757/

Thanks!

/Claes