RFR (S): 8009232: Improve stats gathering code for reference processor

[Jesper Wilhelmsson]

Looks good!

Minor nit:
EventGCReferenceProcessing probably should be called EventGCReferenceStatistics

Fix it'n'ship it! :-)
/Jesper


On 5/3/13 10:36 AM, Erik Helin wrote:
> All,
>
> based on internal feedback, I've updated the change.
>
> The ReferenceProcessorStats class is now no longer a C++ "friend" with the
> ReferenceProcessor class. Furthermore, the method
> ReferenceProcessor::process_discovered_reflist now returns the number of
> discovered references.
>
> I have also renamed GCTrace::report_gc_reference_processing to
> GCTrace::report_gc_reference_stats and
> GCTrace::send_gc_reference_processing_event to
> GCTrace::send_gc_reference_stats_event. This was done because the name
> of the event was previously changed from vm/gc/reference/processing to
> vm/gc/reference/statistics.
>
> New webrev:
> http://cr.openjdk.java.net/~ehelin/8009232/webrev.01/
>
> Thanks,
> Erik
>
> On 03/01/2013 12:34 PM, Erik Helin wrote:
>> Hi all,
>>
>> this change refactors the way the reference processing statistics are
>> being collected from the reference processor.
>>
>> Summary:
>> Before, the statistics were collected by calling
>> ReferenceProcessor::collect_statistics immediately after a call to
>> ReferenceProcessor::process_discovered_references. With this change, the
>> method process_discovered_references instead returns
>> the statistics.
>>
>> The benefit is that there is now no need to keep track of an internal
>> state in ReferenceProcessor since the ReferenceProcessorStats can be put
>> on the stack in process_discovered_references. Furthermore, the code is
>> more maintainable, since the old code required the calls to
>> process_discovered_references and collect_statistics to go "hand in
>> hand". Now, one only has to care about the call to
>> process_discovered_references.
>>
>> Webrev:
>> http://cr.openjdk.java.net/~ehelin/8009232/webrev.00/
>>
>> Bug:
>> https://jbs.oracle.com/bugs/browse/JDK-8009232
>>
>> Testing:
>> JPRT
>>
>> Thanks,
>> Erik
>