review request for JDK-8013461 There is a symbol AsyncGetCallTrace in libjvm.symbols that does not exist in minimal/libjvm.a when DEBUG_LEVEL == release

[JOSEPH PROVINO]

On 5/21/2013 4:00 PM, Oleg Mazurov wrote:
> Though formally not part of the Solaris Studio team any more here is 
> my opinion based on my recollection of how I implemented interaction 
> with the JVM via AsyncGetCallTrace.
> It's looked up using dlsym. If the symbol is not there Java callstack 
> collection is shut down. I understand in your case even JVMTI is not 
> there so the dlsym call will not be made.
> From that perspective there is no difference whether the symbol is 
> present and returns an error code or not present at all.

Oleg, then it sounds like what we have will work.

Thanks for the quick reply.

joe

>
>     -- Oleg
>
> On 5/21/2013 12:19 PM, JOSEPH PROVINO wrote:
>>
>> On 5/21/2013 3:16 PM, serguei.spitsyn at oracle.com wrote:
>>> On 5/21/13 11:26 AM, JOSEPH PROVINO wrote:
>>>>
>>>> On 5/21/2013 2:23 PM, Staffan Larsen wrote:
>>>>> On 21 maj 2013, at 17:35, JOSEPH PROVINO 
>>>>> <joseph.provino at oracle.com> wrote:
>>>>>
>>>>>> On 5/21/2013 3:06 AM, David Holmes wrote:
>>>>>>> Hi Staffan,
>>>>>>>
>>>>>>> On 21/05/2013 4:49 PM, Staffan Larsen wrote:
>>>>>>>> On 21 maj 2013, at 04:34, David Holmes 
>>>>>>>> <David.Holmes at oracle.com> wrote:
>>>>>>>>
>>>>>>>>> <added servicability>
>>>>>>>>>
>>>>>>>>> Hi Joe,
>>>>>>>>>
>>>>>>>>> As I have previously stated you copied the struct definitions 
>>>>>>>>> instead of moving them outside the ifdef.
>>>>>>>>>
>>>>>>>>> Serviceability folk: we are particularly interested in whether 
>>>>>>>>> the use of ticks_no_class_load is deemed appropriate in this 
>>>>>>>>> situation. Who will be consuming this value?
>>>>>>>> Since you have opted for the simple fix of having an exported 
>>>>>>>> but non-functional AsyncGetCallTrace instead of actually 
>>>>>>>> removing the symbol from the symbol files (which is the 
>>>>>>>> proposed solution in the bug report),
>>>>>>> That would be a simpler solution semantically but the only way I 
>>>>>>> can see to do that is to use a text replacement mechanism in the 
>>>>>>> build files - as is done for the dynamic vtable symbols. I find 
>>>>>>> that less appealing than simply exporting an interface that is 
>>>>>>> configured to report an error (which is essentially what all the 
>>>>>>> optional interfaces do under the minimal VM).
>>>>>>>
>>>>>>>> I would like you to include a comment about this in the source. 
>>>>>>>> Right now it's very unclear why there is an exported function 
>>>>>>>> that only returns an error.
>>>>>>>>
>>>>>>>> As to the appropriate return value, I don't know. The only 
>>>>>>>> caller should be the Sun Studio profiler,
>>>> Does anyone know where to find instructions on how to run the 
>>>> collector which would get the error return value?
>>>>>>>>   and I'm not sure how it will handle this case if ever run. 
>>>>>>>> The possible return values aren't very well documented.
>>>>>>> I guess we need to try and run it to find out.
>>>>>> Okay, do either of you feel strongly about how this should be 
>>>>>> fixed -- return an error or remove the symbol?
>>>>> No, I don't feel strongly either way, but a comment in the code 
>>>>> would be nice.
>>>> How much effort should I put into finding out what Sun Studio 
>>>> profiler does when it gets -1?
>>>
>>> Let's ask the Solaris Studio guys directly.
>>> I'm adding Oleg to the mailing list.
>>>
>>> Oleg,
>>>
>>> Could you, please, share your view on this problem?
>>
>> In particular what will the Sun Studio Profiler collector do if it 
>> gets the error
>>
>> trace->num_frames = ticks_no_class_load; // -1
>>
>> Thanks.
>>
>> joe
>>
>>>
>>>
>>> Thanks,
>>> Serguei
>>>
>>>
>>>
>>>
>>>>
>>>> joe
>>>>
>>>>>
>>>>> Thanks,
>>>>> /Staffan
>>>>>
>>>>>
>>>>>> joe
>>>>>>
>>>>>>> Thanks,
>>>>>>> David
>>>>>>>
>>>>>>>> /Staffan
>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>> David
>>>>>>>>>
>>>>>>>>> On 21/05/2013 5:10 AM, JOSEPH PROVINO wrote:
>>>>>>>>>> The change is to include forte.cpp in the minimal jvm but to
>>>>>>>>>> conditionalize the code so that
>>>>>>>>>> only AsyncGetCallTrace() is defined with the minimal jvm.
>>>>>>>>>>
>>>>>>>>>> Webrev is here: 
>>>>>>>>>> http://cr.openjdk.java.net/~jprovino/8013461/webrev.00/
>>>>>>>>>>
>>>>>>>>>>   * JDK-8013461 
>>>>>>>>>> <https://jbs.oracle.com/bugs/browse/JDK-8013461>There is
>>>>>>>>>>     a symbol AsyncGetCallTrace in libjvm.symbols that does 
>>>>>>>>>> not exist in
>>>>>>>>>>     minimal/libjvm.a when DEBUG_LEVEL == release
>>>>>>>>>> <https://jbs.oracle.com/bugs/browse/JDK-8013461>
>>>>>>>>>>
>>>>>>>>>> Thanks.
>>>>>>>>>>
>>>>>>>>>> joe
>>>>>>>>>>
>>>>>>>>>>
>>>>
>>>
>>
>