PING: RFR: JDK-8164913: JVMTI.agent_load dcmd should show useful error message

[Dmitry Samersoff]

Yasumasa,

I'll look closely to the fix.

Please, notice:

1. We typically avoid printing attach error messages on
the target VM side.

2. We are in RDP1 for jdk9.

   http://mail.openjdk.java.net/pipermail/jdk9-dev/2016-August/004777.html

-Dmitry

On 2016-09-05 16:25, Yasumasa Suenaga wrote:
> PING: Could you review and sponsor it?
> 
>>       http://cr.openjdk.java.net/~ysuenaga/JDK-8164913/webrev.01/
> 
> 
> Thanks,
> 
> Yasumasa
> 
> 
> On 2016/09/01 12:47, Yasumasa Suenaga wrote:
>> Hi all,
>>
>> I think RDP1 has been started.
>> Cannot I fix this?
>>
>> This problem is that jcmd shows incorrect status when JVMTI agent
>> cannot be attached.
>> I think this problem should be fixed in 9 GA.
>> The users who want.to <http://want.to> attach JVMTI agent want to know
>> whether it succeed.
>>
>> Yasumasa
>>
>>
>> 2016/08/29 15:42 "Yasumasa Suenaga" <yasuenag at gmail.com
>> <mailto:yasuenag at gmail.com>>:
>>
>>         This comment no longer matches the code and should be deleted:
>>
>>         2412       // Agent_OnAttach executed so completion status is
>> JNI_OK
>>         2413       st->print_cr("return code: %d", result);
>>
>>
>>     Thanks David!
>>     I removed it in new webrev.
>>
>>       http://cr.openjdk.java.net/~ysuenaga/JDK-8164913/webrev.01/
>> <http://cr.openjdk.java.net/~ysuenaga/JDK-8164913/webrev.01/>
>>
>>
>>     Yasumasa
>>
>>
>>     On 2016/08/29 12:59, David Holmes wrote:
>>
>>         Hi Yasumasa,
>>
>>         On 28/08/2016 10:47 PM, Yasumasa Suenaga wrote:
>>
>>             Hi all,
>>
>>             If we try to attach invalid JVMTI agent via
>> JVMTI.agent_load dcmd, we
>>             will get
>>             "Command executed successfully". However, it implies error in
>>             JVMTIAgentLoadDCmd.
>>
>>             This message is from JCmd.java when jcmd does not receive
>> output from
>>             target VM.
>>             So we should send error message from JVMTIAgentLoadDCmd.
>>
>>             I uploaded a webrev for it. Could you review it?
>>
>>              
>> http://cr.openjdk.java.net/~ysuenaga/JDK-8164913/webrev.00/
>> <http://cr.openjdk.java.net/~ysuenaga/JDK-8164913/webrev.00/>
>>
>>
>>         This seems reasonable.
>>
>>         src/share/vm/prims/jvmtiExport.cpp
>>
>>         This comment no longer matches the code and should be deleted:
>>
>>         2412       // Agent_OnAttach executed so completion status is
>> JNI_OK
>>         2413       st->print_cr("return code: %d", result);
>>
>>         Thanks,
>>         David
>>
>>             I cannot access JPRT.
>>             So I need a sponsor.
>>
>>
>>             Thanks,
>>
>>             Yasumasa
>>


-- 
Dmitry Samersoff
Oracle Java development team, Saint Petersburg, Russia
* I would love to change the world, but they won't give me the sources.