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

[serguei.spitsyn at oracle.com]

Hi Chris,

Good catch.
I agree, for consistency the enqueue_event() is better to follow the 
JvmtiDeferredEventQueue::enqueue() to avoid slowdebug minimal build 
failures.

New patch is:

diff --git a/src/hotspot/share/prims/jvmtiThreadState.hpp 
b/src/hotspot/share/prims/jvmtiThreadState.hpp
--- a/src/hotspot/share/prims/jvmtiThreadState.hpp
+++ b/src/hotspot/share/prims/jvmtiThreadState.hpp
@@ -396,7 +396,7 @@
    void set_should_post_on_exceptions(bool val) { 
_thread->set_should_post_on_exceptions_flag(val ? JNI_TRUE : JNI_FALSE); }

    // Thread local event queue, which doesn't require taking the 
Service_lock.
-  void enqueue_event(JvmtiDeferredEvent* event);
+  void enqueue_event(JvmtiDeferredEvent* event) NOT_JVMTI_RETURN;
    void post_events(JvmtiEnv* env);
    void run_nmethod_entry_barriers();
  };

Thanks,
Serguei

On 1/6/20 6:39 PM, Chris Plummer wrote:
> 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
>>>
>>
>>
>
>