[PATCH RFC 0/2] Add linux/ppc64 support for Hotspot serviceability agent to read core files

[Vladimir Kozlov]

Volker or Goetz, can you help Maynard to create bugs and prepare webrevs 
on cr.openjdk for these 3 changes?

Thanks,
Vladimir

On 11/14/14 10:09 AM, Maynard Johnson wrote:
> When Hotspot SA tools jmap, jstack, and jsadebugd are run against a core file, they fail with the following runtime exception:
>
>       OS/CPU combination linux/ppc64 not yet supported
>
> I will post a patch set that adds this support.  The patch set consists of the following patches:
>
> PATCH 1/2: Updates to non-Java files to support linux/ppc64 Hotspot SA with core files
>
> PATCH 2/2: New PPC64 class files (and updates to generic files) to support linux/ppc64 Hotspot SA with core files
>
> These two patches apply cleanly to a November 13 pull of the jdk9-dev upstream sources.
>
> ------------
> Open issues:
> ------------
>    1) The jstack tool does not print a stack entry for the 'main()' method of the Java
>       workload (attached) under test.  For example:
>
>       (Note:  Addresses and method signatures elided for brevity.)
>
>         Thread 24358: (state = IN_JAVA, current Java SP = null
>         )
>          - java.lang.String.getChars(...) @bci=58, line=814, pc=..., Method*=... (Compiled frame; ... imprecise)
>          - test.run_test() @bci=80, line=33, pc=..., Method*=... (Compiled frame)
>       ==> (Expect an entry for test.main() here)
>
>    2) The jstack tool sometimes prints what appears to be two complete stacks for the Java workload. For example:
>
>         Thread 24779: (state = IN_JAVA, current Java SP = null
>         )
>          - java.lang.String.getChars(...) @bci=58, line=814, pc=..., Method*=... (Compiled frame; ... imprecise)
>          - test.run_test() @bci=80, line=33, pc=..., Method*=... (Compiled frame)
>          - test.get_my_chars(...) @bci=39, line=15, pc=..., Method*=... (Compiled frame)
>          - test.run_test() @bci=92, line=34, pc=..., Method*=... (Compiled frame)
>
>         Again, the 'test.main' method is missing, but there's also the anomaly of the
>         test.run_test' method showing up twice in the stack, implying that it is called
>         by 'test.get_my_chars' at line 15.  But that that is not accurate. In fact, run_test
>         does call String.getChars at line 33 *and* it calls test.get_my_chars at line 34 --
>         but these are totally distinct call graphs.  Somehow, we are seeing these two distinct
>         stacks in the core file, which seems impossible.
>
> ---------
>
> Any help offered on these two open issues would be greatly appreciated.
>
> -Maynard
>