RFR: 8205577: parallel/TestPrintGCDetailsVerbose.java fails assertion

[Thomas Schatzl]

Hi,

On Wed, 2018-06-27 at 01:03 -0400, Kim Barrett wrote:
> Please review this fix of an assertion failure during ParallelGC
> young collections.
> 
> We have a task (thread) walking the code cache, copying and
> forwarding oop references in those cached nmethods containing
> scavengable (e.g. young) oops.  After the oops in an nmethod are
> processed, a second pass is made to determine whether any of the oops
> are still scavengable, removing the nmethod from the list containing
> scavengable oops.  That speeds up future collection cycles.
> 
[...]
> The solution being taken here is to change that logging to no longer
> attempt to print the object.  Printing an object while in the middle
> of a copying GC, especially one that is parallel, seems quite risky,
> so let's just not do that.

Looks good.

Thomas