RFR: 8189440: Event tracing macros for allocation and weak oops processing

[Erik Gahlin]

Hi David,

> Hi Erik,
>
> On 18/10/2017 12:34 PM, Erik Gahlin wrote:
>> Hi,
>>
>> Could I have a review of a change that adds two macros to be used 
>> with event-based JVM tracing.
>>
>> Bug:
>> https://bugs.openjdk.java.net/browse/JDK-8189440
>>
>> Webrev:
>> http://cr.openjdk.java.net/~egahlin/8189440_0
>
> Reviewed - though all somewhat mysterious in isolation :(
>
Thanks for the review!

Sorry about the mysterious part.

> My only real query is in jniHandles.cpp:
>
>    JvmtiExport::weak_oops_do(is_alive, f);
> +  TRACE_WEAK_OOPS_DO(is_alive, f);
>
> Can't/shouldn't the tracing be done inside weak_oops_do?
>
Stefan Karlsson has a change out for review and if integrated before 
this one, I will move the TRACE_WEAK_OOPS_DO into weak_oops_do in 
weakProcessor.cpp.

Thanks
Erik