RFR(XXS): 8236124: Minimal VM slowdebug build failed after JDK-8212160

[Chris Plummer]

Hi Serguei,

JvmtiDeferredEventQueue::enqueue() is a NOP for minimal builds, so it 
can be called even for minimalVM builds:

   void enqueue(JvmtiDeferredEvent event) NOT_JVMTI_RETURN;

The changes for JDK-8212160 seem to have put some wrapper code around 
its use, resulting in ServiceThread::enqueue_deferred_event() and 
JvmtiThreadState::enqueue_event() being added. Shouldn't NOP 
implementations also have been done for them?

thanks,

Chris

On 1/6/20 6:35 PM, Chris Plummer wrote:
> Hold your horses. I have questions. Working on them now. Please don't 
> push.
>
> thanks,
>
> Chris
>
> On 1/6/20 6:29 PM, coleen.phillimore at oracle.com wrote:
>> This looks trivial.  Thank you for fixing it.
>> Coleen
>>
>> On 1/6/20 9:18 PM, serguei.spitsyn at oracle.com wrote:
>>> Please, review a trivial fix for bug:
>>>   https://bugs.openjdk.java.net/browse/JDK-8236124
>>>
>>> Patch suggested by A. Shipilev:
>>>
>>> diff --git a/src/hotspot/share/code/nmethod.cpp 
>>> b/src/hotspot/share/code/nmethod.cpp
>>> --- a/src/hotspot/share/code/nmethod.cpp
>>> +++ b/src/hotspot/share/code/nmethod.cpp
>>> @@ -1601,7 +1601,7 @@
>>>        ServiceThread::enqueue_deferred_event(&event);
>>>      } else {
>>>        // This enters the nmethod barrier outside in the caller.
>>> -      state->enqueue_event(&event);
>>> +      JVMTI_ONLY(state->enqueue_event(&event));
>>>      }
>>>    }
>>>  }
>>>
>>>
>>> Summary:
>>>   The slowdebug build was broken by the fix of JDK-8212160 which 
>>> introduced new function: enqueue_event().
>>>   The fix is to call it only if the JVM TI is enabled.
>>>
>>> Testing:
>>>   Ran slowdebug build locally.
>>>
>>> Thanks,
>>> Serguei
>>
>
>