8232592: <Unknown compiled code> is shown in jstack mixed mode

[Yasumasa Suenaga]

Thanks Chris and Paul!

Yasumasa

On 2019/10/23 5:29, Hohensee, Paul wrote:
> +1. Thanks, Chris and Yasumasa.
> 
> Paul
> 
> On 10/22/19, 1:02 PM, "serviceability-dev on behalf of Chris Plummer" <serviceability-dev-bounces at openjdk.java.net on behalf of chris.plummer at oracle.com> wrote:
> 
>      Hi Yasumasa,
>      
>      Looks good.
>      
>      thanks,
>      
>      Chris
>      
>      On 10/21/19 7:02 PM, Yasumasa Suenaga wrote:
>      > Hi Chris,
>      >
>      > Thanks for your comment! I uploaded new webrev:
>      >
>      >   http://cr.openjdk.java.net/~ysuenaga/JDK-8232592/webrev.01/
>      >
>      >
>      >> So what does it mean if it is an NMethod but is not native and names
>      >> != null. Should this ever happen? It seems odd that we don't print
>      >> out the frame type in this case, and also don't call printUnknown().
>      >
>      > I guess it might happen when call nmethod from JNI.
>      > It would be handled as valid compiled code.
>      >
>      > ```
>      >  166                       // print java frames, if any
>      >  167                       if (names != null && names.length != 0) {
>      >  168                          // print java frame(s)
>      >  169                          for (int i = 0; i < names.length; i++) {
>      >  170                              out.println(names[i]);
>      >  171                          }
>      >  172                       }
>      >  ```
>      >
>      >
>      > Thanks,
>      >
>      > Yasumasa
>      >
>      >
>      > On 2019/10/22 2:25, Chris Plummer wrote:
>      >> Hi Yasumasa,
>      >>
>      >> The call to getJavaNames() is not needed if the method is native. It
>      >> should be moved into the else block:
>      >>
>      >>                              if (cb.isNMethod()) {
>      >>                                 if (cb.isNativeMethod()) {
>      >> out.print(((CompiledMethod)cb).getMethod().externalNameAndSignature());
>      >>                                    long diff = pc.minus(cb.codeBegin());
>      >>                                    if (diff != 0L) {
>      >>                                      out.print(" + 0x" +
>      >> Long.toHexString(diff));
>      >>                                    }
>      >>                                    out.println(" (Native method)");
>      >>                                 } else {
>      >>                                     names = getJavaNames(th,
>      >> f.localVariableBase());
>      >>                                     if (names == null || names.length
>      >> == 0) {
>      >>                                         // just print compiled code,
>      >> if can't determine method
>      >> out.println("<Unknown compiled code>");
>      >>                                     }
>      >>                                 }
>      >>                              } else if (cb.isBufferBlob()) {
>      >>
>      >> So what does it mean if it is an NMethod but is not native and names
>      >> != null. Should this ever happen? It seems odd that we don't print
>      >> out the frame type in this case, and also don't call printUnknown().
>      >>
>      >> thanks,
>      >>
>      >> Chris
>      >>
>      >> On 10/18/19 1:38 AM, Yasumasa Suenaga wrote:
>      >>> Hi all,
>      >>>
>      >>> Please review this change.
>      >>>
>      >>>   JBS: https://bugs.openjdk.java.net/browse/JDK-8232592
>      >>>   webrev: http://cr.openjdk.java.net/~ysuenaga/JDK-8232592/webrev.00/
>      >>>
>      >>> I run `jhsdb jstack --mixed` to JShellToolProvider process, then I
>      >>> saw <Unknown compiled code>
>      >>> in the stack as below:
>      >>>
>      >>> ```
>      >>> "process reaper" #13 daemon prio=10 tid=0x00007f959c328000
>      >>> nid=0x1285 runnable [0x00007f9578025000]
>      >>>    java.lang.Thread.State: RUNNABLE
>      >>>    JavaThread state: _thread_in_native
>      >>> 0x00007f95a27c5596 __waitpid + 0x56
>      >>> 0x00007f958c601d79 <Unknown compiled code>
>      >>> 0x00007f9585c5b4ac * java.lang.ProcessHandleImpl$1.run() bci:8
>      >>> line:138 (Compiled frame)
>      >>> ```
>      >>>
>      >>> 0x7f958c601d79 is native method. jstack mixed mode should handle it.
>      >>> This patch passed all tests on submit repo
>      >>> (mach5-one-ysuenaga-JDK-8232592-20191018-0600-6011163).
>      >>>
>      >>>
>      >>> Thanks,
>      >>>
>      >>> Yasumasa
>      >>
>      
>      
>