RFR (S): 8151614: Improve logging in concurrent mark code

[sangheon]

Hi Thomas,

Looks nice especially for combining logging and trace event.
Thanks for cleaning up this.

One minor comment, could you update the copyright in logPrefix.hpp 
before pushing?

Sangheon


On 03/10/2016 09:02 AM, Thomas Schatzl wrote:
> Hi all,
>
>    can I have reviews for this change that improves the logging code for
> concurrent mark by:
>
> - removes the need to have two scoped objects, one for logging, one for
> JFR for every phase
> - tries to make the phase names correspond to method names
> - add a "marking" tag to marking related log messages
> - removes a duplicate log message ("Restart for overflow") at different
> levels
>
> CR:
> https://bugs.openjdk.java.net/browse/JDK-8151614
> Webrev:
> http://cr.openjdk.java.net/~tschatzl/8151614/webrev/
> Testing:
> jprt
>
>
> Thanks,
>    Thomas