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

[Yasumasa Suenaga]

Hi Dmitry,

I'll look closely to the fix.

Thanks!

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

My change will not print error message(s) on the target VM side.


Yasumasa


On 2016/09/05 22:46, Dmitry Samersoff wrote:

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" <yasue...@gmail.com
<mailto:yasue...@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