RFR: JDK-8152690: main thread does not have native thread name

Yasumasa Suenaga yasuenag at gmail.com
Tue Apr 26 09:22:52 UTC 2016


Hi David,

> I thought about being able to save/restore the original pending exception but could not see a simple way to restore it - ie just by poking it back into the thread's pending exception field. The problem with using env->Throw is that it acts like the initial throwing of the exception and will have a number of side-effects that then get doubled up:
> - logging statements (UL and Event logging)
> - OOM counting

Thanks, I understood.

>>> so note that we are potentially calling DetachCurrentThread with an
>>> exception pending - which is prohibited by JNI**, but which we
>>> actually rely on for desired operation as DetachCurrentThread calls
>>> thread->exit() which performs uncaught exception handling (ie it
>>> prints the exception message and stacktrace) and then clears the
>>> exception! (Hence DestroyJavaVM is not called with any pending
>>> exceptions.)

I think we can call uncaught exception handler before calling DestroyJavaVM().
I added it in new webrev for jdk:

   http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.08/hotspot/
   http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.08/jdk/

DispatchUncaughtException() in java.c emulates uncaught exception handler
call in JavaThread::exit().
I think this patch can provide the solution for our issue.

Could you check it?


Thanks,

Yasumasa


On 2016/04/26 14:16, David Holmes wrote:
> On 26/04/2016 1:11 PM, Yasumasa Suenaga wrote:
>> Hi David, Kumar,
>>
>> I think that we should evacuate original exception before DestroyJavaVM
>> thread name is set.
>>
>>    http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.07/hotspot/
>>    http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.07/jdk/
>>
>> I added it to LEAVE macro in new webrev.
>
> BTW: in the LEAVE macro, stylistically all the code should be in the do { } while(false); loop. I overlooked that initially.
>
>> I tested it with following code. It works fine.
>>
>> -------------
>> public void main(String[] args){
>>    throw new RuntimeException("test");
>> }
>> -------------
>>
>> What do you think about it?
>
> I thought about being able to save/restore the original pending exception but could not see a simple way to restore it - ie just by poking it back into the thread's pending exception field. The problem with using env->Throw is that it acts like the initial throwing of the exception and will have a number of side-effects that then get doubled up:
> - logging statements (UL and Event logging)
> - OOM counting
>
> I'm not sure whether that is acceptable or not
>
> That aside you should check if orig_throwable is non-null before clearing to avoid an unnecessary JNI call.
>
> Also "Resume original exception" -> "Restore any original exception"
>
> Thanks,
> David
> -----
>
>>
>> Thanks,
>>
>> Yasumasa
>>
>>
>> On 2016/04/26 11:16, David Holmes wrote:
>>> Hi Yasumasa, Kumar,
>>>
>>> Turns out this change breaks the behaviour of the launcher in the case
>>> that main() completes by throwing an exception.
>>>
>>> What we have in the launcher is:
>>>
>>>     (*env)->CallStaticVoidMethod(env, mainClass, mainID, mainArgs);
>>>     ret = (*env)->ExceptionOccurred(env) == NULL ? 0 : 1;
>>>     LEAVE();
>>>
>>> where LEAVE would have expanded to:
>>>
>>>         if ((*vm)->DetachCurrentThread(vm) != JNI_OK) { \
>>>             JLI_ReportErrorMessage(JVM_ERROR2); \
>>>             ret = 1; \
>>>         } \
>>>         if (JNI_TRUE) { \
>>>             (*vm)->DestroyJavaVM(vm); \
>>>             return ret; \
>>>         } \
>>>
>>> so note that we are potentially calling DetachCurrentThread with an
>>> exception pending - which is prohibited by JNI**, but which we
>>> actually rely on for desired operation as DetachCurrentThread calls
>>> thread->exit() which performs uncaught exception handling (ie it
>>> prints the exception message and stacktrace) and then clears the
>>> exception! (Hence DestroyJavaVM is not called with any pending
>>> exceptions.)
>>>
>>> **JNI spec needs to be modified here.
>>>
>>> With the current change we have now inserted the following at the
>>> start of LEAVE:
>>>
>>>         SetNativeThreadName(env, "DestroyJavaVM");  \
>>>         if ((*env)->ExceptionOccurred(env)) { \
>>>             (*env)->ExceptionClear(env);                           \
>>>         } \
>>>
>>> this has two unintended consequences:
>>>
>>> 1. SetNativeThreadName itself calls a number of JNI methods, with the
>>> exception pending - which is not permitted. So straight away where we
>>> have:
>>>
>>>    NULL_CHECK(cls = FindBootStrapClass(env, "java/lang/Thread"));
>>>
>>> FindBootStrapClass calls JVM_FindClassFromBootLoader, which make calls
>>> using the VM's CHECK_NULL macro - which checks for a pending exception
>>> (which it finds) and returns NULL. So the jli NULL_CHECK macro then
>>> reports a JNI error:
>>>
>>> Error: A JNI error has occurred, please check your installation and
>>> try again
>>>
>>>
>>> 2. There is no longer an exception from main() for DetachCurrentThread
>>> to report, so we exit with a return code of 1 as required, but don't
>>> report the exception message/stacktrace.
>>>
>>> I don't see a reasonable solution for this other than abandoning the
>>> attempt to change the name from "main" to "DestroyJavaVM" - which if
>>> we can't do, I question the utility of setting the name in the first
>>> place (while it might be useful in some circumstances [when main() is
>>> running] it will cause confusion in others [when main() has exited]).
>>>
>>> David
>>> -----
>>>
>>> On 25/04/2016 3:47 PM, David Holmes wrote:
>>>> Looks good to me.
>>>>
>>>> I'll sponsor this "tomorrow".
>>>>
>>>> Thanks,
>>>> David
>>>>
>>>> On 23/04/2016 11:24 PM, Yasumasa Suenaga wrote:
>>>>> Hi Kumar,
>>>>>
>>>>> Thank you for your comment!
>>>>> I've fixed them and uploaded new webrev. Could you review again?
>>>>>
>>>>>    http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.06/hotspot/
>>>>>    http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.06/jdk/
>>>>>
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Yasumasa
>>>>>
>>>>>
>>>>> On 2016/04/23 1:14, Kumar Srinivasan wrote:
>>>>>>
>>>>>> Also a couple of minor suggestions:
>>>>>>
>>>>>> - * Set native thread name as possible.
>>>>>> + * Set native thread name if possible.
>>>>>>
>>>>>>
>>>>>> +      /*
>>>>>> -       * We can clear pending exception because exception at this
>>>>>> point
>>>>>> -       * is not critical.
>>>>>> +       */
>>>>>>
>>>>>> +      /*
>>>>>> +       * Clear non critical pending exceptions at this point.
>>>>>> +       */
>>>>>>
>>>>>> Thanks
>>>>>> Kumar
>>>>>>
>>>>>>> Hi,
>>>>>>>
>>>>>>> This is in the wrong place:
>>>>>>>
>>>>>>> 1715     if ((*env)->ExceptionOccurred(env)) {
>>>>>>> 1716       /*
>>>>>>> 1717        * We can clear pending exception because exception at
>>>>>>> this point
>>>>>>> 1718        * is not critical.
>>>>>>> 1719        */
>>>>>>> 1720       (*env)->ExceptionClear(env);
>>>>>>> 1721     }
>>>>>>>
>>>>>>> This above needs to be after
>>>>>>>  391     SetNativeThreadName(env, "main");
>>>>>>>  392
>>>>>>>
>>>>>>> Here is why, supposing 1704 through 1711, returns a NULL,
>>>>>>> but have also encountered an exception. In which case
>>>>>>> the method SetNativeThreadName will return to the caller, as
>>>>>>> if nothing has happened, because NULL_CHECK simply checks for NULL
>>>>>>> and returns to the caller. This will cause the caller to enter
>>>>>>> the VM with exceptions.
>>>>>>>
>>>>>>> Kumar
>>>>>>>
>>>>>>>
>>>>>>> On 4/22/2016 5:11 AM, Yasumasa Suenaga wrote:
>>>>>>>> Hi David,
>>>>>>>>
>>>>>>>>> I don't think we need to report the exception, but can just ignore
>>>>>>>>> it. Either way we have to clear the exception before continuing.
>>>>>>>>
>>>>>>>> I've fixed it in new webrev:
>>>>>>>>
>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.05/hotspot/
>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.05/jdk/
>>>>>>>>
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>>
>>>>>>>> Yasumasa
>>>>>>>>
>>>>>>>>
>>>>>>>> On 2016/04/22 15:33, David Holmes wrote:
>>>>>>>>> On 22/04/2016 1:36 PM, Yasumasa Suenaga wrote:
>>>>>>>>>> Hi all,
>>>>>>>>>>
>>>>>>>>>> I have uploaded webrev.04 as below.
>>>>>>>>>> Could you review again?
>>>>>>>>>>
>>>>>>>>>>  >  - hotspot:
>>>>>>>>>>  >
>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.04/hotspot/
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Looks fine.
>>>>>>>>>
>>>>>>>>>>  >
>>>>>>>>>>  >  - jdk:
>>>>>>>>>>  > http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.04/jdk/
>>>>>>>>>
>>>>>>>>> As per private email (but repeated here on the record) in java.c:
>>>>>>>>>
>>>>>>>>> 715     if ((*env)->ExceptionOccurred(env)) {
>>>>>>>>> 1716       JLI_ReportExceptionDescription(env);
>>>>>>>>> 1717     }
>>>>>>>>>
>>>>>>>>> I don't think we need to report the exception, but can just ignore
>>>>>>>>> it. Either way we have to clear the exception before continuing.
>>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>> David
>>>>>>>>>
>>>>>>>>>> Thanks,
>>>>>>>>>>
>>>>>>>>>> Yasumasa
>>>>>>>>>>
>>>>>>>>>> 2016/04/19 22:43 "Yasumasa Suenaga" <yasuenag at gmail.com
>>>>>>>>>> <mailto:yasuenag at gmail.com>>:
>>>>>>>>>>  >
>>>>>>>>>>  > Hi David,
>>>>>>>>>>  >
>>>>>>>>>>  > Thank you for your comment.
>>>>>>>>>>  > I uploaded new webrev. Could you review again?
>>>>>>>>>>  >
>>>>>>>>>>  >  - hotspot:
>>>>>>>>>>  >
>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.04/hotspot/
>>>>>>>>>>
>>>>>>>>>>  >
>>>>>>>>>>  >  - jdk:
>>>>>>>>>>  > http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.04/jdk/
>>>>>>>>>>  >
>>>>>>>>>>  >
>>>>>>>>>>  >> That aside I'm not sure why you do this so late in the
>>>>>>>>>> process, I
>>>>>>>>>> would have done it immediately after here:
>>>>>>>>>>  >
>>>>>>>>>>  >
>>>>>>>>>>  > I think that native thread name ("main") should be set just
>>>>>>>>>> before
>>>>>>>>>>  > main method call.
>>>>>>>>>>  > However, main thread is already started, so I moved it as you
>>>>>>>>>> suggested.
>>>>>>>>>>  >
>>>>>>>>>>  >
>>>>>>>>>>  >> One thing I dislike about the current structure is that we
>>>>>>>>>> have to
>>>>>>>>>> go from char* to java.lang.String to call setNativeName which then
>>>>>>>>>> calls
>>>>>>>>>> JVM_SetNativeThreadName which converts the j.l.String back to a
>>>>>>>>>> char* !
>>>>>>>>>>  >
>>>>>>>>>>  >
>>>>>>>>>>  > SoI proposed to export new JVM function to set native thread
>>>>>>>>>> name with
>>>>>>>>>>  > const char *.
>>>>>>>>>>  >
>>>>>>>>>>  >
>>>>>>>>>>  > Thanks,
>>>>>>>>>>  >
>>>>>>>>>>  > Yasumasa
>>>>>>>>>>  >
>>>>>>>>>>  >
>>>>>>>>>>  >
>>>>>>>>>>  > On 2016/04/19 14:04, David Holmes wrote:
>>>>>>>>>>  >>
>>>>>>>>>>  >> Hi Yasumasa,
>>>>>>>>>>  >>
>>>>>>>>>>  >> Thanks for persevering with this to get it into the current
>>>>>>>>>> form.
>>>>>>>>>> Sorry I haven't been able to do a detailed review until now.
>>>>>>>>>>  >>
>>>>>>>>>>  >> On 19/04/2016 9:28 AM, Yasumasa Suenaga wrote:
>>>>>>>>>>  >>>
>>>>>>>>>>  >>> Hi Gerard,
>>>>>>>>>>  >>>
>>>>>>>>>>  >>> 2016/04/19 3:14 "Gerard Ziemski" <gerard.ziemski at oracle.com
>>>>>>>>>> <mailto:gerard.ziemski at oracle.com>
>>>>>>>>>>  >>> <mailto:gerard.ziemski at oracle.com
>>>>>>>>>> <mailto:gerard.ziemski at oracle.com>>>:
>>>>>>>>>>  >>>  >
>>>>>>>>>>  >>>  > hi Yasumasa,
>>>>>>>>>>  >>>  >
>>>>>>>>>>  >>>  > Nice work. I have 2 questions:
>>>>>>>>>>  >>>  >
>>>>>>>>>>  >>>  > ========
>>>>>>>>>>  >>>  > File: java.c
>>>>>>>>>>  >>>  >
>>>>>>>>>>  >>>  > #1 Shouldn’t we be checking for
>>>>>>>>>> “(*env)->ExceptionOccurred(env)”
>>>>>>>>>>  >>> after every single JNI call? In this example instead of
>>>>>>>>>> NULL_CHECK,
>>>>>>>>>>  >>> should we be using CHECK_EXCEPTION_NULL_LEAVE macro?
>>>>>>>>>>  >>>
>>>>>>>>>>  >>> It is not critical if we encounter error at JNI function call
>>>>>>>>>> because
>>>>>>>>>>  >>> we cannot set native thread name only.
>>>>>>>>>>  >>> So I think that we do not need to leave from launcher
>>>>>>>>>> process.
>>>>>>>>>>  >>
>>>>>>>>>>  >>
>>>>>>>>>>  >> I agree we do not need to abort if an exception occurs (and in
>>>>>>>>>> fact
>>>>>>>>>> I don't think an exception is even possible from this code),
>>>>>>>>>> but we
>>>>>>>>>> should ensure any pending exception is cleared before any
>>>>>>>>>> futher JNI
>>>>>>>>>> calls might be made. Note that NULL_CHECK is already used
>>>>>>>>>> extensively
>>>>>>>>>> throughout the launcher code - so if this usage is wrong then it
>>>>>>>>>> is all
>>>>>>>>>> wrong! More on this code below ...
>>>>>>>>>>  >>
>>>>>>>>>>  >> Other comments:
>>>>>>>>>>  >>
>>>>>>>>>>  >> hotspot/src/share/vm/prims/jvm.cpp
>>>>>>>>>>  >>
>>>>>>>>>>  >> Please add a comment to the method now that you removed the
>>>>>>>>>> internal
>>>>>>>>>> comment:
>>>>>>>>>>  >>
>>>>>>>>>>  >> // Sets the native thread name for a JavaThread. If
>>>>>>>>>> specifically
>>>>>>>>>>  >> // requested JNI-attached threads can also have their native
>>>>>>>>>> name set;
>>>>>>>>>>  >> // otherwise we do not modify JNI-attached threads as it may
>>>>>>>>>> interfere
>>>>>>>>>>  >> // with the application that created them.
>>>>>>>>>>  >>
>>>>>>>>>>  >> ---
>>>>>>>>>>  >>
>>>>>>>>>>  >> jdk/src/java.base/share/classes/java/lang/Thread.java
>>>>>>>>>>  >>
>>>>>>>>>>  >> Please add the following comments:
>>>>>>>>>>  >>
>>>>>>>>>>  >> +            // Don't modify JNI-attached threads
>>>>>>>>>>  >>               setNativeName(name, false);
>>>>>>>>>>  >>
>>>>>>>>>>  >> + // May be called directly via JNI or reflection (when
>>>>>>>>>> permitted) to
>>>>>>>>>>  >> + // allow JNI-attached threads to set their native name
>>>>>>>>>>  >>   private native void setNativeName(String name, boolean
>>>>>>>>>> allowAttachedThread);
>>>>>>>>>>  >>
>>>>>>>>>>  >> ---
>>>>>>>>>>  >>
>>>>>>>>>>  >> jd/src/java.base/share/native/libjli/java.c
>>>>>>>>>>  >>
>>>>>>>>>>  >> 328 #define LEAVE() \
>>>>>>>>>>  >> 329     SetNativeThreadName(env, "DestroyJavaVM"); \
>>>>>>>>>>  >>
>>>>>>>>>>  >> I was going to suggest this be set later, but realized we have
>>>>>>>>>> to be
>>>>>>>>>> attached to do this and that happens inside DestroyJavaVM. :)
>>>>>>>>>>  >>
>>>>>>>>>>  >> +     /* Set native thread name. */
>>>>>>>>>>  >> +     SetNativeThreadName(env, "main");
>>>>>>>>>>  >>
>>>>>>>>>>  >> The comment is redundant given the name of the method. That
>>>>>>>>>> aside
>>>>>>>>>> I'm not sure why you do this so late in the process, I would have
>>>>>>>>>> done
>>>>>>>>>> it immediately after here:
>>>>>>>>>>  >>
>>>>>>>>>>  >>   386     if (!InitializeJVM(&vm, &env, &ifn)) {
>>>>>>>>>>  >>   387         JLI_ReportErrorMessage(JVM_ERROR1);
>>>>>>>>>>  >>   388         exit(1);
>>>>>>>>>>  >>   389     }
>>>>>>>>>>  >>   +       SetNativeThreadName(env, "main");
>>>>>>>>>>  >>
>>>>>>>>>>  >>
>>>>>>>>>>  >> + /**
>>>>>>>>>>  >> +  * Set native thread name as possible.
>>>>>>>>>>  >> +  */
>>>>>>>>>>  >>
>>>>>>>>>>  >> Other than the as->if change I'm unclear where the "possible"
>>>>>>>>>> bit
>>>>>>>>>> comes into play - why would it not be possible?
>>>>>>>>>>  >>
>>>>>>>>>>  >> 1705     NULL_CHECK(cls = FindBootStrapClass(env,
>>>>>>>>>> "java/lang/Thread"));
>>>>>>>>>>  >> 1706     NULL_CHECK(currentThreadID =
>>>>>>>>>> (*env)->GetStaticMethodID(env,
>>>>>>>>>> cls,
>>>>>>>>>>  >> 1707 "currentThread",
>>>>>>>>>> "()Ljava/lang/Thread;"));
>>>>>>>>>>  >> 1708     NULL_CHECK(currentThread =
>>>>>>>>>> (*env)->CallStaticObjectMethod(env, cls,
>>>>>>>>>>  >> 1709 currentThreadID));
>>>>>>>>>>  >> 1710     NULL_CHECK(setNativeNameID = (*env)->GetMethodID(env,
>>>>>>>>>> cls,
>>>>>>>>>>  >> 1711 "setNativeName",
>>>>>>>>>> "(Ljava/lang/String;Z)V"));
>>>>>>>>>>  >> 1712     NULL_CHECK(nameString = (*env)->NewStringUTF(env,
>>>>>>>>>> name));
>>>>>>>>>>  >> 1713     (*env)->CallVoidMethod(env, currentThread,
>>>>>>>>>> setNativeNameID,
>>>>>>>>>>  >> 1714                            nameString, JNI_TRUE);
>>>>>>>>>>  >>
>>>>>>>>>>  >> As above NULL_CHECK is fine here, but we should check for and
>>>>>>>>>> clear
>>>>>>>>>> any pending exception after CallVoidMethod.
>>>>>>>>>>  >>
>>>>>>>>>>  >> One thing I dislike about the current structure is that we
>>>>>>>>>> have to
>>>>>>>>>> go from char* to java.lang.String to call setNativeName which then
>>>>>>>>>> calls
>>>>>>>>>> JVM_SetNativeThreadName which converts the j.l.String back to a
>>>>>>>>>> char* !
>>>>>>>>>> Overall I wonder about the affect on startup cost. But if there
>>>>>>>>>> is an
>>>>>>>>>> issue we can revisit this.
>>>>>>>>>>  >>
>>>>>>>>>>  >> Thanks,
>>>>>>>>>>  >> David
>>>>>>>>>>  >> -----
>>>>>>>>>>  >>
>>>>>>>>>>  >>
>>>>>>>>>>  >>>  > #2 Should the comment for “SetNativeThreadName” be “Set
>>>>>>>>>> native
>>>>>>>>>> thread
>>>>>>>>>>  >>> name if possible.” not "Set native thread name as possible.”?
>>>>>>>>>>  >>>
>>>>>>>>>>  >>> Sorry for my bad English :-)
>>>>>>>>>>  >>>
>>>>>>>>>>  >>> Thanks,
>>>>>>>>>>  >>>
>>>>>>>>>>  >>> Yasumasa
>>>>>>>>>>  >>>
>>>>>>>>>>  >>>  > cheers
>>>>>>>>>>  >>>  >
>>>>>>>>>>  >>>  > > On Apr 16, 2016, at 4:29 AM, Yasumasa Suenaga
>>>>>>>>>> <yasuenag at gmail.com <mailto:yasuenag at gmail.com>
>>>>>>>>>>  >>> <mailto:yasuenag at gmail.com <mailto:yasuenag at gmail.com>>>
>>>>>>>>>> wrote:
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > > Hi David,
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > > I uploaded new webrev:
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > > - hotspot:
>>>>>>>>>>  >>>  > >
>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.03/hotspot/
>>>>>>>>>>
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > > - jdk:
>>>>>>>>>>  >>>  > >
>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.03/jdk/
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > >> it won't work unless you change the semantics of
>>>>>>>>>> setName so I'm
>>>>>>>>>>  >>> not sure what you were thinking here. To take advantage of an
>>>>>>>>>> arg
>>>>>>>>>> taking
>>>>>>>>>>  >>> JVM_SetNativThreadName you would need to call it directly as
>>>>>>>>>> no Java
>>>>>>>>>>  >>> code will call it . ???
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > > I added a flag for setting native thread name to
>>>>>>>>>> JNI-attached
>>>>>>>>>> thread.
>>>>>>>>>>  >>>  > > This change can set native thread name if main thread
>>>>>>>>>> changes to
>>>>>>>>>>  >>> JNI-attached thread.
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > > Thanks,
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > > Yasumasa
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > >
>>>>>>>>>>  >>>  > > On 2016/04/16 16:11, David Holmes wrote:
>>>>>>>>>>  >>>  > >> On 16/04/2016 3:27 PM, Yasumasa Suenaga wrote:
>>>>>>>>>>  >>>  > >>> Hi David,
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>>> That change in behaviour may be a problem, it
>>>>>>>>>> could be
>>>>>>>>>> considered a
>>>>>>>>>>  >>>  > >>>> regression that setName stops setting the native
>>>>>>>>>> thread
>>>>>>>>>> main, even
>>>>>>>>>>  >>>  > >>>> though we never really intended it to work in the
>>>>>>>>>> first place.
>>>>>>>>>>  >>> :( Such
>>>>>>>>>>  >>>  > >>>> a change needs to go through CCC.
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> I understood.
>>>>>>>>>>  >>>  > >>> Can I send CCC request?
>>>>>>>>>>  >>>  > >>> (I'm jdk 9 commiter, but I'm not employee at Oracle.)
>>>>>>>>>>  >>>  > >>
>>>>>>>>>>  >>>  > >> Sorry you can't file a CCC request, you would need a
>>>>>>>>>> sponsor for
>>>>>>>>>>  >>> that. But at this stage I don't think I agree with the
>>>>>>>>>> proposed change
>>>>>>>>>>  >>> because of the change in behaviour - there's no way to
>>>>>>>>>> restore the
>>>>>>>>>>  >>> "broken" behaviour.
>>>>>>>>>>  >>>  > >>
>>>>>>>>>>  >>>  > >>> I want to continue to discuss about it on JDK-8154331
>>>>>>>>>> [1].
>>>>>>>>>>  >>>  > >>
>>>>>>>>>>  >>>  > >> Okay we can do that.
>>>>>>>>>>  >>>  > >>
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>>> Further, we expect the launcher to use the supported
>>>>>>>>>> JNI
>>>>>>>>>>  >>> interface (as
>>>>>>>>>>  >>>  > >>>> other processes would), not the internal JVM
>>>>>>>>>> interface that
>>>>>>>>>>  >>> exists for
>>>>>>>>>>  >>>  > >>>> the JDK sources to communicate with the JVM.
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> I think that we do not use JVM interface if we add new
>>>>>>>>>> method in
>>>>>>>>>>  >>>  > >>> LauncherHelper as below:
>>>>>>>>>>  >>>  > >>> ----------------
>>>>>>>>>>  >>>  > >>> diff -r f02139a1ac84
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>> src/java.base/share/classes/sun/launcher/LauncherHelper.java
>>>>>>>>>>  >>>  > >>> ---
>>>>>>>>>> a/src/java.base/share/classes/sun/launcher/LauncherHelper.java
>>>>>>>>>>  >>>  > >>> Wed Apr 13 14:19:30 2016 +0000
>>>>>>>>>>  >>>  > >>> +++
>>>>>>>>>> b/src/java.base/share/classes/sun/launcher/LauncherHelper.java
>>>>>>>>>>  >>>  > >>> Sat Apr 16 11:25:53 2016 +0900
>>>>>>>>>>  >>>  > >>> @@ -960,4 +960,8 @@
>>>>>>>>>>  >>>  > >>>          else
>>>>>>>>>>  >>>  > >>>              return md.toNameAndVersion() + " (" + loc
>>>>>>>>>> + ")";
>>>>>>>>>>  >>>  > >>>      }
>>>>>>>>>>  >>>  > >>> +
>>>>>>>>>>  >>>  > >>> +    static void setNativeThreadName(String name) {
>>>>>>>>>>  >>>  > >>> + Thread.currentThread().setName(name);
>>>>>>>>>>  >>>  > >>> +    }
>>>>>>>>>>  >>>  > >>
>>>>>>>>>>  >>>  > >> You could also make that call via JNI directly, so not
>>>>>>>>>> sure the
>>>>>>>>>>  >>> helper adds much here. But it won't work unless you change
>>>>>>>>>> the
>>>>>>>>>> semantics
>>>>>>>>>>  >>> of setName so I'm not sure what you were thinking here. To
>>>>>>>>>> take
>>>>>>>>>>  >>> advantage of an arg taking JVM_SetNativThreadName you would
>>>>>>>>>> need to
>>>>>>>>>> call
>>>>>>>>>>  >>> it directly as no Java code will call it . ???
>>>>>>>>>>  >>>  > >>
>>>>>>>>>>  >>>  > >> David
>>>>>>>>>>  >>>  > >> -----
>>>>>>>>>>  >>>  > >>
>>>>>>>>>>  >>>  > >>>  }
>>>>>>>>>>  >>>  > >>> diff -r f02139a1ac84
>>>>>>>>>> src/java.base/share/native/libjli/java.c
>>>>>>>>>>  >>>  > >>> --- a/src/java.base/share/native/libjli/java.c    Wed
>>>>>>>>>> Apr 13
>>>>>>>>>> 14:19:30
>>>>>>>>>>  >>>  > >>> 2016 +0000
>>>>>>>>>>  >>>  > >>> +++ b/src/java.base/share/native/libjli/java.c    Sat
>>>>>>>>>> Apr 16
>>>>>>>>>> 11:25:53
>>>>>>>>>>  >>>  > >>> 2016 +0900
>>>>>>>>>>  >>>  > >>> @@ -125,6 +125,7 @@
>>>>>>>>>>  >>>  > >>>  static void PrintUsage(JNIEnv* env, jboolean
>>>>>>>>>> doXUsage);
>>>>>>>>>>  >>>  > >>>  static void ShowSettings(JNIEnv* env, char
>>>>>>>>>> *optString);
>>>>>>>>>>  >>>  > >>>  static void ListModules(JNIEnv* env, char
>>>>>>>>>> *optString);
>>>>>>>>>>  >>>  > >>> +static void SetNativeThreadName(JNIEnv* env, char
>>>>>>>>>> *name);
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>>  static void SetPaths(int argc, char **argv);
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> @@ -325,6 +326,7 @@
>>>>>>>>>>  >>>  > >>>   * mainThread.isAlive() to work as expected.
>>>>>>>>>>  >>>  > >>>   */
>>>>>>>>>>  >>>  > >>>  #define LEAVE() \
>>>>>>>>>>  >>>  > >>> + SetNativeThreadName(env, "DestroyJavaVM"); \
>>>>>>>>>>  >>>  > >>>      do { \
>>>>>>>>>>  >>>  > >>>          if ((*vm)->DetachCurrentThread(vm) != JNI_OK)
>>>>>>>>>> { \
>>>>>>>>>>  >>>  > >>> JLI_ReportErrorMessage(JVM_ERROR2); \
>>>>>>>>>>  >>>  > >>> @@ -488,6 +490,9 @@
>>>>>>>>>>  >>>  > >>>      mainArgs = CreateApplicationArgs(env, argv,
>>>>>>>>>> argc);
>>>>>>>>>>  >>>  > >>> CHECK_EXCEPTION_NULL_LEAVE(mainArgs);
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> +    /* Set native thread name. */
>>>>>>>>>>  >>>  > >>> + SetNativeThreadName(env, "main");
>>>>>>>>>>  >>>  > >>> +
>>>>>>>>>>  >>>  > >>>      /* Invoke main method. */
>>>>>>>>>>  >>>  > >>> (*env)->CallStaticVoidMethod(env, mainClass, mainID,
>>>>>>>>>> mainArgs);
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> @@ -1686,6 +1691,22 @@
>>>>>>>>>>  >>>  > >>>                                   joptString);
>>>>>>>>>>  >>>  > >>>  }
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> +/**
>>>>>>>>>>  >>>  > >>> + * Set native thread name as possible.
>>>>>>>>>>  >>>  > >>> + */
>>>>>>>>>>  >>>  > >>> +static void
>>>>>>>>>>  >>>  > >>> +SetNativeThreadName(JNIEnv *env, char *name)
>>>>>>>>>>  >>>  > >>> +{
>>>>>>>>>>  >>>  > >>> +    jmethodID setNativeThreadNameID;
>>>>>>>>>>  >>>  > >>> +    jstring nameString;
>>>>>>>>>>  >>>  > >>> +    jclass cls = GetLauncherHelperClass(env);
>>>>>>>>>>  >>>  > >>> +    NULL_CHECK(cls);
>>>>>>>>>>  >>>  > >>> + NULL_CHECK(setNativeThreadNameID =
>>>>>>>>>>  >>> (*env)->GetStaticMethodID(env, cls,
>>>>>>>>>>  >>>  > >>> + "setNativeThreadName", "(Ljava/lang/String;)V"));
>>>>>>>>>>  >>>  > >>> +    NULL_CHECK(nameString = (*env)->NewStringUTF(env,
>>>>>>>>>> name));
>>>>>>>>>>  >>>  > >>> + (*env)->CallStaticVoidMethod(env, cls,
>>>>>>>>>> setNativeThreadNameID,
>>>>>>>>>>  >>>  > >>> nameString);
>>>>>>>>>>  >>>  > >>> +}
>>>>>>>>>>  >>>  > >>> +
>>>>>>>>>>  >>>  > >>>  /*
>>>>>>>>>>  >>>  > >>>   * Prints default usage or the Xusage message, see
>>>>>>>>>>  >>>  > >>> sun.launcher.LauncherHelper.java
>>>>>>>>>>  >>>  > >>>   */
>>>>>>>>>>  >>>  > >>> ----------------
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> So I want to add new arg to JVM_SetNativeThreadName().
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>>> However this is still a change to the exported JVM
>>>>>>>>>> interface and so
>>>>>>>>>>  >>>  > >>>> has to be approved.
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> Do you mean that this change needs CCC?
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> Thanks,
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> Yasumasa
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> [1]
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>
>>>>>>>>>> http://mail.openjdk.java.net/pipermail/hotspot-runtime-dev/2016-April/019034.html
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>>
>>>>>>>>>>  >>>  > >>> On 2016/04/16 7:26, David Holmes wrote:
>>>>>>>>>>  >>>  > >>>> On 15/04/2016 11:20 PM, Yasumasa Suenaga wrote:
>>>>>>>>>>  >>>  > >>>>> Hi David,
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>>> I think it is a bug based on the comment here:
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> JavaThread(bool is_attaching_via_jni = false); //
>>>>>>>>>> for main
>>>>>>>>>>  >>> thread and
>>>>>>>>>>  >>>  > >>>>>> JNI attached threads
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>> I filed it to JBS as JDK-8154331.
>>>>>>>>>>  >>>  > >>>>> I will send review request to hotspot-runtime-dev.
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>>> Though that will introduce a change in behaviour by
>>>>>>>>>> itself as
>>>>>>>>>>  >>> setName
>>>>>>>>>>  >>>  > >>>>>> will no longer set the native name for the main
>>>>>>>>>> thread.
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>> I know.
>>>>>>>>>>  >>>  > >>>>
>>>>>>>>>>  >>>  > >>>> That change in behaviour may be a problem, it
>>>>>>>>>> could be
>>>>>>>>>> considered a
>>>>>>>>>>  >>>  > >>>> regression that setName stops setting the native
>>>>>>>>>> thread
>>>>>>>>>> main, even
>>>>>>>>>>  >>>  > >>>> though we never really intended it to work in the
>>>>>>>>>> first place.
>>>>>>>>>>  >>> :( Such
>>>>>>>>>>  >>>  > >>>> a change needs to go through CCC.
>>>>>>>>>>  >>>  > >>>>
>>>>>>>>>>  >>>  > >>>>> I checked changeset history.
>>>>>>>>>>  >>>  > >>>>> JVM_SetNativeThreadName() was introduced in
>>>>>>>>>> JDK-7098194,
>>>>>>>>>> and it is
>>>>>>>>>>  >>>  > >>>>> backported JDK 8.
>>>>>>>>>>  >>>  > >>>>
>>>>>>>>>>  >>>  > >>>> Yes this all came in as part of the OSX port in 7u2.
>>>>>>>>>>  >>>  > >>>>
>>>>>>>>>>  >>>  > >>>>> However, this function seems to be called from
>>>>>>>>>>  >>> Thread#setNativeName()
>>>>>>>>>>  >>>  > >>>>> only.
>>>>>>>>>>  >>>  > >>>>> In addition, Thread#setNativeName() is private
>>>>>>>>>> method.
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>> Thus I think that we can add an argument to
>>>>>>>>>>  >>> JVM_SetNativeThreadName()
>>>>>>>>>>  >>>  > >>>>> for force setting.
>>>>>>>>>>  >>>  > >>>>> (e.g. "bool forced")
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>> It makes a change of JVM API.
>>>>>>>>>>  >>>  > >>>>> However, this function is NOT public, so I think we
>>>>>>>>>> can
>>>>>>>>>> add one
>>>>>>>>>>  >>> more
>>>>>>>>>>  >>>  > >>>>> argument.
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>> What do you think about this?
>>>>>>>>>>  >>>  > >>>>> If it is accepted, we can set native thread name
>>>>>>>>>> from Java
>>>>>>>>>>  >>> launcher.
>>>>>>>>>>  >>>  > >>>>
>>>>>>>>>>  >>>  > >>>> The private/public aspect of the Java API is not
>>>>>>>>>> really at
>>>>>>>>>>  >>> issue. Yes
>>>>>>>>>>  >>>  > >>>> we would add another arg to the JVM function to allow
>>>>>>>>>> it to
>>>>>>>>>> apply to
>>>>>>>>>>  >>>  > >>>> JNI-attached threads as well (I'd prefer the arg
>>>>>>>>>> reflect that
>>>>>>>>>>  >>> not just
>>>>>>>>>>  >>>  > >>>> "force"). However this is still a change to the
>>>>>>>>>> exported JVM
>>>>>>>>>>  >>> interface
>>>>>>>>>>  >>>  > >>>> and so has to be approved. Further, we expect the
>>>>>>>>>> launcher to
>>>>>>>>>>  >>> use the
>>>>>>>>>>  >>>  > >>>> supported JNI interface (as other processes would),
>>>>>>>>>> not the
>>>>>>>>>> internal
>>>>>>>>>>  >>>  > >>>> JVM interface that exists for the JDK sources to
>>>>>>>>>> communicate
>>>>>>>>>>  >>> with the
>>>>>>>>>>  >>>  > >>>> JVM.
>>>>>>>>>>  >>>  > >>>>
>>>>>>>>>>  >>>  > >>>> David
>>>>>>>>>>  >>>  > >>>> -----
>>>>>>>>>>  >>>  > >>>>
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>> Yasumasa
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>>
>>>>>>>>>>  >>>  > >>>>> On 2016/04/15 19:16, David Holmes wrote:
>>>>>>>>>>  >>>  > >>>>>> Hi Yasumasa,
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> On 15/04/2016 6:53 PM, Yasumasa Suenaga wrote:
>>>>>>>>>>  >>>  > >>>>>>> Hi David,
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>> The fact that the "main" thread is not tagged as
>>>>>>>>>> being a
>>>>>>>>>>  >>> JNI-attached
>>>>>>>>>>  >>>  > >>>>>>>> thread seems accidental to me
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>> Should I file it to JBS?
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> I think it is a bug based on the comment here:
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> JavaThread(bool is_attaching_via_jni = false); //
>>>>>>>>>> for main
>>>>>>>>>>  >>> thread and
>>>>>>>>>>  >>>  > >>>>>> JNI attached threads
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> Though that will introduce a change in behaviour by
>>>>>>>>>> itself as
>>>>>>>>>>  >>> setName
>>>>>>>>>>  >>>  > >>>>>> will no longer set the native name for the main
>>>>>>>>>> thread.
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>>> I think that we can fix as below:
>>>>>>>>>>  >>>  > >>>>>>> ---------------
>>>>>>>>>>  >>>  > >>>>>>> diff -r 52aa0ee93b32
>>>>>>>>>> src/share/vm/runtime/thread.cpp
>>>>>>>>>>  >>>  > >>>>>>> --- a/src/share/vm/runtime/thread.cpp   Thu Apr 14
>>>>>>>>>> 13:31:11
>>>>>>>>>>  >>> 2016 +0200
>>>>>>>>>>  >>>  > >>>>>>> +++ b/src/share/vm/runtime/thread.cpp   Fri Apr 15
>>>>>>>>>> 17:50:10
>>>>>>>>>>  >>> 2016 +0900
>>>>>>>>>>  >>>  > >>>>>>> @@ -3592,7 +3592,7 @@
>>>>>>>>>>  >>>  > >>>>>>>  #endif // INCLUDE_JVMCI
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>    // Attach the main thread to this os thread
>>>>>>>>>>  >>>  > >>>>>>> - JavaThread* main_thread = new JavaThread();
>>>>>>>>>>  >>>  > >>>>>>> + JavaThread* main_thread = new JavaThread(true);
>>>>>>>>>>  >>>  > >>>>>>> main_thread->set_thread_state(_thread_in_vm);
>>>>>>>>>>  >>>  > >>>>>>> main_thread->initialize_thread_current();
>>>>>>>>>>  >>>  > >>>>>>>    // must do this before set_active_handles
>>>>>>>>>>  >>>  > >>>>>>> @@ -3776,6 +3776,9 @@
>>>>>>>>>>  >>>  > >>>>>>>    // Notify JVMTI agents that VM initialization
>>>>>>>>>> is complete
>>>>>>>>>>  >>> - nop if
>>>>>>>>>>  >>>  > >>>>>>> no agents.
>>>>>>>>>>  >>>  > >>>>>>> JvmtiExport::post_vm_initialized();
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>> +  // Change attach status to "attached"
>>>>>>>>>>  >>>  > >>>>>>> + main_thread->set_done_attaching_via_jni();
>>>>>>>>>>  >>>  > >>>>>>> +
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> I think we can do this straight after the
>>>>>>>>>> JavaThread
>>>>>>>>>> constructor.
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>>>    if (TRACE_START() != JNI_OK) {
>>>>>>>>>>  >>>  > >>>>>>> vm_exit_during_initialization("Failed to start
>>>>>>>>>> tracing
>>>>>>>>>>  >>>  > >>>>>>> backend.");
>>>>>>>>>>  >>>  > >>>>>>>    }
>>>>>>>>>>  >>>  > >>>>>>> ---------------
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>> If it wants to name its native threads then it is
>>>>>>>>>> free
>>>>>>>>>> to do so,
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>> Currently, JVM_SetNativeThreadName() cannot change
>>>>>>>>>> native
>>>>>>>>>>  >>> thread name
>>>>>>>>>>  >>>  > >>>>>>> when the caller thread is JNI-attached thread.
>>>>>>>>>>  >>>  > >>>>>>> However, I think that it should be changed if Java
>>>>>>>>>> developer
>>>>>>>>>>  >>> calls
>>>>>>>>>>  >>>  > >>>>>>> Thread#setName() explicitly.
>>>>>>>>>>  >>>  > >>>>>>> It is not the same of changing native thread
>>>>>>>>>> name at
>>>>>>>>>>  >>>  > >>>>>>> Threads::create_vm().
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>> If it is allowed, I want to fix
>>>>>>>>>> SetNativeThreadName() as
>>>>>>>>>> below.
>>>>>>>>>>  >>>  > >>>>>>> What do you think about this?
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> The decision to not change the name of JNI-attached
>>>>>>>>>> threads was a
>>>>>>>>>>  >>>  > >>>>>> deliberate one** - this functionality originated
>>>>>>>>>> with the OSX
>>>>>>>>>>  >>> port and
>>>>>>>>>>  >>>  > >>>>>> it was reported that the initial feedback with this
>>>>>>>>>> feature was to
>>>>>>>>>>  >>>  > >>>>>> ensure it didn't mess with thread names that had
>>>>>>>>>> been set by
>>>>>>>>>>  >>> the host
>>>>>>>>>>  >>>  > >>>>>> process. If we do as you propose then we will just
>>>>>>>>>> have an
>>>>>>>>>>  >>>  > >>>>>> inconsistency for people to complain about: "why
>>>>>>>>>> does my
>>>>>>>>>>  >>> native thread
>>>>>>>>>>  >>>  > >>>>>> only have a name if I call
>>>>>>>>>> cur.setName(cur.getName()) ?"
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> ** If you follow the bugs and related
>>>>>>>>>> discussions on
>>>>>>>>>> this, the
>>>>>>>>>>  >>>  > >>>>>> semantics and limitations (truncation, current
>>>>>>>>>> thread only,
>>>>>>>>>>  >>> non-JNI
>>>>>>>>>>  >>>  > >>>>>> threads only) of setting the native thread name
>>>>>>>>>> were supposed
>>>>>>>>>>  >>> to be
>>>>>>>>>>  >>>  > >>>>>> documented in the release notes - but as far as I
>>>>>>>>>> can see
>>>>>>>>>> that
>>>>>>>>>>  >>> never
>>>>>>>>>>  >>>  > >>>>>> happened. :(
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> My position on this remains that if it is desirable
>>>>>>>>>> for
>>>>>>>>>> the main
>>>>>>>>>>  >>>  > >>>>>> thread (and DestroyJavaVM thread) to have native
>>>>>>>>>> names
>>>>>>>>>> then the
>>>>>>>>>>  >>>  > >>>>>> launcher needs to be setting them using the
>>>>>>>>>> available
>>>>>>>>>> platform
>>>>>>>>>>  >>> APIs.
>>>>>>>>>>  >>>  > >>>>>> Unfortunately this is complicated - as evidenced by
>>>>>>>>>> the VM
>>>>>>>>>>  >>> code for
>>>>>>>>>>  >>>  > >>>>>> this - due to the need to verify API availability.
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> Any change in behaviour in relation to
>>>>>>>>>> Thread.setName would
>>>>>>>>>>  >>> have to go
>>>>>>>>>>  >>>  > >>>>>> through our CCC process I think. But a change in
>>>>>>>>>> the launcher
>>>>>>>>>>  >>> would
>>>>>>>>>>  >>>  > >>>>>> not.
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> Sorry.
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>> David
>>>>>>>>>>  >>>  > >>>>>> -----
>>>>>>>>>>  >>>  > >>>>>>
>>>>>>>>>>  >>>  > >>>>>>> ---------------
>>>>>>>>>>  >>>  > >>>>>>> --- a/src/share/vm/prims/jvm.cpp        Thu Apr 14
>>>>>>>>>> 13:31:11
>>>>>>>>>>  >>> 2016 +0200
>>>>>>>>>>  >>>  > >>>>>>> +++ b/src/share/vm/prims/jvm.cpp        Fri Apr 15
>>>>>>>>>> 17:50:10
>>>>>>>>>>  >>> 2016 +0900
>>>>>>>>>>  >>>  > >>>>>>> @@ -3187,7 +3187,7 @@
>>>>>>>>>>  >>>  > >>>>>>> JavaThread* thr =
>>>>>>>>>> java_lang_Thread::thread(java_thread);
>>>>>>>>>>  >>>  > >>>>>>>    // Thread naming only supported for the current
>>>>>>>>>> thread,
>>>>>>>>>>  >>> doesn't
>>>>>>>>>>  >>>  > >>>>>>> work
>>>>>>>>>>  >>>  > >>>>>>> for
>>>>>>>>>>  >>>  > >>>>>>>    // target threads.
>>>>>>>>>>  >>>  > >>>>>>> -  if (Thread::current() == thr &&
>>>>>>>>>>  >>> !thr->has_attached_via_jni()) {
>>>>>>>>>>  >>>  > >>>>>>> +  if (Thread::current() == thr) {
>>>>>>>>>>  >>>  > >>>>>>>      // we don't set the name of an attached
>>>>>>>>>> thread to avoid
>>>>>>>>>>  >>> stepping
>>>>>>>>>>  >>>  > >>>>>>>      // on other programs
>>>>>>>>>>  >>>  > >>>>>>>      const char *thread_name =
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>
>>>>>>>>>> java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>> ---------------
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>> Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>
>>>>>>>>>>  >>>  > >>>>>>> On 2016/04/15 13:32, David Holmes wrote:
>>>>>>>>>>  >>>  > >>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>> On 15/04/2016 1:11 AM, Yasumasa Suenaga wrote:
>>>>>>>>>>  >>>  > >>>>>>>>> Roger,
>>>>>>>>>>  >>>  > >>>>>>>>> Thanks for your comment!
>>>>>>>>>>  >>>  > >>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>> David,
>>>>>>>>>>  >>>  > >>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>> I'll wait to see what Kumar thinks about
>>>>>>>>>> this. I
>>>>>>>>>> don't like
>>>>>>>>>>  >>>  > >>>>>>>>>>>> exposing
>>>>>>>>>>  >>>  > >>>>>>>>>>>> a new JVM function this way.
>>>>>>>>>>  >>>  > >>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>> I tried to call Thread#setName() after
>>>>>>>>>> initializing VM
>>>>>>>>>> (before
>>>>>>>>>>  >>>  > >>>>>>>>> calling
>>>>>>>>>>  >>>  > >>>>>>>>> main method),
>>>>>>>>>>  >>>  > >>>>>>>>> I could set native thread name.
>>>>>>>>>>  >>>  > >>>>>>>>> However, DestroyJavaVM() calls
>>>>>>>>>> AttachCurrentThread().
>>>>>>>>>> So we
>>>>>>>>>>  >>> can't
>>>>>>>>>>  >>>  > >>>>>>>>> set
>>>>>>>>>>  >>>  > >>>>>>>>> native thread name for DestroyJavaVM.
>>>>>>>>>>  >>>  > >>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>> Right - I came to the same realization earlier
>>>>>>>>>> this
>>>>>>>>>> morning.
>>>>>>>>>>  >>> Which,
>>>>>>>>>>  >>>  > >>>>>>>> unfortunately, takes me back to the basic premise
>>>>>>>>>> here that
>>>>>>>>>>  >>> we don't
>>>>>>>>>>  >>>  > >>>>>>>> set the name of threads not created by the JVM.
>>>>>>>>>> The fact
>>>>>>>>>>  >>> that the
>>>>>>>>>>  >>>  > >>>>>>>> "main" thread is not tagged as being a
>>>>>>>>>> JNI-attached
>>>>>>>>>> thread seems
>>>>>>>>>>  >>>  > >>>>>>>> accidental to me - so JVM_SetNativeThreadName is
>>>>>>>>>> only
>>>>>>>>>> working by
>>>>>>>>>>  >>>  > >>>>>>>> accident for the initial attach, and can't be
>>>>>>>>>> used for the
>>>>>>>>>>  >>>  > >>>>>>>> DestroyJavaVM part - which leaves the thread
>>>>>>>>>> inconsistently
>>>>>>>>>>  >>> named at
>>>>>>>>>>  >>>  > >>>>>>>> the native level.
>>>>>>>>>>  >>>  > >>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>> I'm afraid my view here is that the launcher has
>>>>>>>>>> to be
>>>>>>>>>>  >>> treated like
>>>>>>>>>>  >>>  > >>>>>>>> any other process that might host a JVM. If it
>>>>>>>>>> wants to
>>>>>>>>>> name its
>>>>>>>>>>  >>>  > >>>>>>>> native threads then it is free to do so, but I
>>>>>>>>>> would not be
>>>>>>>>>>  >>> exporting
>>>>>>>>>>  >>>  > >>>>>>>> a function from the JVM to do that - it would
>>>>>>>>>> have to
>>>>>>>>>> use the OS
>>>>>>>>>>  >>>  > >>>>>>>> specific API's for that on a platform-by-platform
>>>>>>>>>> basis.
>>>>>>>>>>  >>>  > >>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>> Sorry.
>>>>>>>>>>  >>>  > >>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>> David
>>>>>>>>>>  >>>  > >>>>>>>> -----
>>>>>>>>>>  >>>  > >>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>> Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>> On 2016/04/14 23:24, Roger Riggs wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>> Hi,
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>> Comments:
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>> jvm.h:  The function names are too similar but
>>>>>>>>>> perform
>>>>>>>>>>  >>> different
>>>>>>>>>>  >>>  > >>>>>>>>>> functions:
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>> -JVM_SetNativeThreadName0 vs
>>>>>>>>>> JVM_SetNativeThreadName
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>> -  The first function applies to the current
>>>>>>>>>> thread, the
>>>>>>>>>>  >>> second
>>>>>>>>>>  >>>  > >>>>>>>>>> one a
>>>>>>>>>>  >>>  > >>>>>>>>>> specific java thread.
>>>>>>>>>>  >>>  > >>>>>>>>>> It would seem useful for there to be a comment
>>>>>>>>>> somewhere
>>>>>>>>>>  >>> about
>>>>>>>>>>  >>>  > >>>>>>>>>> what
>>>>>>>>>>  >>>  > >>>>>>>>>> the new function does.
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>> windows/native/libjli/java_md.c: line 408
>>>>>>>>>> casts to
>>>>>>>>>> (void*)
>>>>>>>>>>  >>>  > >>>>>>>>>> instead of
>>>>>>>>>>  >>>  > >>>>>>>>>> (SetNativeThreadName0_t)
>>>>>>>>>>  >>>  > >>>>>>>>>>    as is done on unix and mac.
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>> - macosx/native/libjli/java_md_macosx.c:
>>>>>>>>>>  >>>  > >>>>>>>>>> - 737: looks wrong to
>>>>>>>>>> overwriteifn->GetCreatedJavaVMs
>>>>>>>>>>  >>> used at
>>>>>>>>>>  >>>  > >>>>>>>>>> line 730
>>>>>>>>>>  >>>  > >>>>>>>>>> - 738  Incorrect indentation; if possible keep
>>>>>>>>>> the cast
>>>>>>>>>>  >>> on the
>>>>>>>>>>  >>>  > >>>>>>>>>> same
>>>>>>>>>>  >>>  > >>>>>>>>>> line as dlsym...
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>> $.02, Roger
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>> On 4/14/2016 9:32 AM, Yasumasa Suenaga wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>> That is an interesting question which I
>>>>>>>>>> haven't had
>>>>>>>>>> time to
>>>>>>>>>>  >>>  > >>>>>>>>>>>> check -
>>>>>>>>>>  >>>  > >>>>>>>>>>>> sorry. If the main thread is considered a
>>>>>>>>>> JNI-attached
>>>>>>>>>>  >>> thread
>>>>>>>>>>  >>>  > >>>>>>>>>>>> then
>>>>>>>>>>  >>>  > >>>>>>>>>>>> my suggestion wont work. If it isn't then my
>>>>>>>>>> suggestion
>>>>>>>>>>  >>> should
>>>>>>>>>>  >>>  > >>>>>>>>>>>> work
>>>>>>>>>>  >>>  > >>>>>>>>>>>> (but it means we have an inconsistency in our
>>>>>>>>>> treatment of
>>>>>>>>>>  >>>  > >>>>>>>>>>>> JNI-attached threads :( )
>>>>>>>>>>  >>>  > >>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>> I ran following program on JDK 9 EA b112,
>>>>>>>>>> and I
>>>>>>>>>> confirmed
>>>>>>>>>>  >>> native
>>>>>>>>>>  >>>  > >>>>>>>>>>> thread name (test) was set.
>>>>>>>>>>  >>>  > >>>>>>>>>>> ---------
>>>>>>>>>>  >>>  > >>>>>>>>>>> public class Sleep{
>>>>>>>>>>  >>>  > >>>>>>>>>>>  public static void main(String[] args) throws
>>>>>>>>>> Exception{
>>>>>>>>>>  >>>  > >>>>>>>>>>> Thread.currentThread().setName("test");
>>>>>>>>>>  >>>  > >>>>>>>>>>> Thread.sleep(3600000);
>>>>>>>>>>  >>>  > >>>>>>>>>>>  }
>>>>>>>>>>  >>>  > >>>>>>>>>>> }
>>>>>>>>>>  >>>  > >>>>>>>>>>> ---------
>>>>>>>>>>  >>>  > >>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>> I'll wait to see what Kumar thinks about
>>>>>>>>>> this. I
>>>>>>>>>> don't like
>>>>>>>>>>  >>>  > >>>>>>>>>>>> exposing
>>>>>>>>>>  >>>  > >>>>>>>>>>>> a new JVM function this way.
>>>>>>>>>>  >>>  > >>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>> I will update webrev after hearing Kumar's
>>>>>>>>>> comment.
>>>>>>>>>>  >>>  > >>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>> Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>> On 2016/04/14 21:32, David Holmes wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>> On 14/04/2016 1:52 PM, Yasumasa Suenaga
>>>>>>>>>> wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> Hi,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> On 2016/04/14 9:34, David Holmes wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> Hi,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> On 14/04/2016 1:28 AM, Yasumasa Suenaga
>>>>>>>>>> wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> Hi David,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> Thanks for your comment.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> I exported new JVM function to set native
>>>>>>>>>> thread
>>>>>>>>>>  >>> name, and JLI
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> uses it
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> in new webrev.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> First the launcher belongs to another
>>>>>>>>>> team so
>>>>>>>>>>  >>> core-libs will
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> need to
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> review and approve this (in particular
>>>>>>>>>> Kumar) -
>>>>>>>>>> now cc'd.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> Thanks!
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> I'm waiting to review :-)
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> Personally I would have used a Java
>>>>>>>>>> upcall to
>>>>>>>>>>  >>> Thread.setName
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> rather
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> than exporting JVM_SetNativeThreadName. No
>>>>>>>>>> hotspot changes
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> needed in
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> that case.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> As I wrote [1] in JBS, I changed to use
>>>>>>>>>> Thread#setName() in
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> Thread#init(),
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> but I could not change native thread name.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>> At Thread.init time the thread is not alive,
>>>>>>>>>> which is
>>>>>>>>>>  >>> why the
>>>>>>>>>>  >>>  > >>>>>>>>>>>> native
>>>>>>>>>>  >>>  > >>>>>>>>>>>> name is not set.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> I guess that caller of main() is JNI
>>>>>>>>>> attached thread.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>> That is an interesting question which I
>>>>>>>>>> haven't had
>>>>>>>>>> time to
>>>>>>>>>>  >>>  > >>>>>>>>>>>> check -
>>>>>>>>>>  >>>  > >>>>>>>>>>>> sorry. If the main thread is considered a
>>>>>>>>>> JNI-attached
>>>>>>>>>>  >>> thread
>>>>>>>>>>  >>>  > >>>>>>>>>>>> then
>>>>>>>>>>  >>>  > >>>>>>>>>>>> my suggestion wont work. If it isn't then my
>>>>>>>>>> suggestion
>>>>>>>>>>  >>> should
>>>>>>>>>>  >>>  > >>>>>>>>>>>> work
>>>>>>>>>>  >>>  > >>>>>>>>>>>> (but it means we have an inconsistency in our
>>>>>>>>>> treatment of
>>>>>>>>>>  >>>  > >>>>>>>>>>>> JNI-attached threads :( )
>>>>>>>>>>  >>>  > >>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>> I'll wait to see what Kumar thinks about
>>>>>>>>>> this. I
>>>>>>>>>> don't like
>>>>>>>>>>  >>>  > >>>>>>>>>>>> exposing
>>>>>>>>>>  >>>  > >>>>>>>>>>>> a new JVM function this way.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>>>> David
>>>>>>>>>>  >>>  > >>>>>>>>>>>> -----
>>>>>>>>>>  >>>  > >>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> Thus I think that we have to provide a
>>>>>>>>>> function to set
>>>>>>>>>>  >>> native
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> thread name.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>> [1]
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>
>>>>>>>>>> https://bugs.openjdk.java.net/browse/JDK-8152690?focusedCommentId=13926851&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13926851
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>> David
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> Could you review again?
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> - hotspot:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>
>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.02/hotspot/
>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> - jdk:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>
>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.02/jdk/
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>> On 2016/04/13 22:00, David Holmes wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> I'll answer on this original thread as
>>>>>>>>>> well ...
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> Hi Yasumasa,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> Please see my updates to the bug (sorry
>>>>>>>>>> have
>>>>>>>>>> been on
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> vacation).
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> This
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> needs to be done in the launcher to be
>>>>>>>>>> correct
>>>>>>>>>> as we
>>>>>>>>>>  >>> do not
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> set the
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> name of threads that attach via JNI,
>>>>>>>>>> which
>>>>>>>>>> includes the
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> "main"
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> thread.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> David
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>> On 31/03/2016 9:49 AM, Yasumasa Suenaga
>>>>>>>>>> wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>> Thanks Robbin,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>> I'm waiting a sponsor and more reviewer
>>>>>>>>>> :-)
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>> Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>> 2016/03/31 5:58 "Robbin Ehn"
>>>>>>>>>> <robbin.ehn at oracle.com <mailto:robbin.ehn at oracle.com>
>>>>>>>>>>  >>> <mailto:robbin.ehn at oracle.com
>>>>>>>>>> <mailto:robbin.ehn at oracle.com>>>:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>> FYI: I'm not a Reviewer.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>> /Robbin
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>> On 03/30/2016 10:55 PM, Robbin Ehn
>>>>>>>>>> wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>> Thanks, looks good.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>> /Robbin
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>> On 03/30/2016 03:47 PM, Yasumasa
>>>>>>>>>> Suenaga wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>> Hi,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>> I uploaded new webrev.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>> Could you review it?
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.01/
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>> Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>> On 2016/03/30 19:10, Robbin Ehn
>>>>>>>>>> wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>> Hi,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>> On 03/30/2016 11:41 AM, Yasumasa
>>>>>>>>>> Suenaga
>>>>>>>>>> wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Hi Robbin,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> 2016/03/30 18:22 "Robbin Ehn"
>>>>>>>>>>  >>> <robbin.ehn at oracle.com <mailto:robbin.ehn at oracle.com>
>>>>>>>>>> <mailto:robbin.ehn at oracle.com <mailto:robbin.ehn at oracle.com>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> <mailto:robbin.ehn at oracle.com
>>>>>>>>>> <mailto:robbin.ehn at oracle.com>
>>>>>>>>>>  >>> <mailto:robbin.ehn at oracle.com
>>>>>>>>>> <mailto:robbin.ehn at oracle.com>>>>:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > Hi Yasumasa,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > On 03/25/2016 12:48 AM, Yasumasa
>>>>>>>>>> Suenaga wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> Hi Robbin,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> 2016/03/25 1:51 "Robbin Ehn"
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> <robbin.ehn at oracle.com
>>>>>>>>>> <mailto:robbin.ehn at oracle.com>
>>>>>>>>>>  >>> <mailto:robbin.ehn at oracle.com <mailto:robbin.ehn at oracle.com>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> <mailto:robbin.ehn at oracle.com
>>>>>>>>>> <mailto:robbin.ehn at oracle.com>
>>>>>>>>>>  >>> <mailto:robbin.ehn at oracle.com
>>>>>>>>>> <mailto:robbin.ehn at oracle.com>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> <mailto:robbin.ehn at oracle.com
>>>>>>>>>> <mailto:robbin.ehn at oracle.com>
>>>>>>>>>>  >>> <mailto:robbin.ehn at oracle.com <mailto:robbin.ehn at oracle.com>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> <mailto:robbin.ehn at oracle.com
>>>>>>>>>> <mailto:robbin.ehn at oracle.com>
>>>>>>>>>>  >>> <mailto:robbin.ehn at oracle.com
>>>>>>>>>> <mailto:robbin.ehn at oracle.com>>>>>:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > Hi Yasumasa,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > I'm not sure why you don't
>>>>>>>>>> set it:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > diff -r ded6ef79c770
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> src/share/vm/runtime/thread.cpp
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > ---
>>>>>>>>>> a/src/share/vm/runtime/thread.cpp   Thu
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Mar 24
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> 13:09:16 2016
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> +0000
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > +++
>>>>>>>>>> b/src/share/vm/runtime/thread.cpp   Thu
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Mar 24
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> 17:40:09 2016
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> +0100
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > @@ -3584,6 +3584,7 @@
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >    JavaThread* main_thread =
>>>>>>>>>> new
>>>>>>>>>>  >>> JavaThread();
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>>  >>> main_thread->set_thread_state(_thread_in_vm);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>> main_thread->initialize_thread_current();
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > +
>>>>>>>>>>  >>> main_thread->set_native_thread_name("main");
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >    // must do this before
>>>>>>>>>>  >>> set_active_handles
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>> main_thread->record_stack_base_and_size();
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>
>>>>>>>>>> main_thread->set_active_handles(JNIHandleBlock::allocate_block());
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > here instead? Am I missing
>>>>>>>>>> something?
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> Native thread name is the same
>>>>>>>>>> to thread
>>>>>>>>>>  >>> name in
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Thread
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> class.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> It is set in c'tor in Thread or
>>>>>>>>>> setName().
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> If you create new thread in Java
>>>>>>>>>> app,
>>>>>>>>>> native
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> thread
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> name
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> will be
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> set at
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> startup. However, main thread is
>>>>>>>>>> already
>>>>>>>>>>  >>> starte
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> in VM.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> Thread name for "main" is set in
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> create_initial_thread().
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> I think that the place of
>>>>>>>>>> setting
>>>>>>>>>> thrrad name
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> should
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> be the
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> same.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > Yes, I see your point. But then
>>>>>>>>>> something like
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> this is
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> nicer, no?
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > ---
>>>>>>>>>> a/src/share/vm/runtime/thread.cpp
>>>>>>>>>>   Tue
>>>>>>>>>>  >>> Mar 29
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> 09:43:05
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> 2016
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> +0200
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > +++
>>>>>>>>>> b/src/share/vm/runtime/thread.cpp
>>>>>>>>>>   Wed
>>>>>>>>>>  >>> Mar 30
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> 10:51:12
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> 2016
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> +0200
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > @@ -981,6 +981,7 @@
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >  // Creates the initial Thread
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >  static oop
>>>>>>>>>> create_initial_thread(Handle
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> thread_group,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> JavaThread*
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> thread,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > TRAPS) {
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > +  static const char*
>>>>>>>>>> initial_thread_name =
>>>>>>>>>>  >>> "main";
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >    Klass* k =
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>
>>>>>>>>>> SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(),
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> true,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> CHECK_NULL);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >    instanceKlassHandle klass
>>>>>>>>>> (THREAD, k);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >    instanceHandle thread_oop =
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>> klass->allocate_instance_handle(CHECK_NULL);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > @@ -988,8 +989,10 @@
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>> java_lang_Thread::set_thread(thread_oop(),
>>>>>>>>>>  >>> thread);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>> java_lang_Thread::set_priority(thread_oop(),
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> NormPriority);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>> thread->set_threadObj(thread_oop());
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > -
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > -  Handle string =
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>> java_lang_String::create_from_str("main",
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> CHECK_NULL);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > +
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > +
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>> thread->set_native_thread_name(initial_thread_name);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > +
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > +  Handle string =
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>> java_lang_String::create_from_str(initial_thread_name,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> CHECK_NULL);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >    JavaValue result(T_VOID);
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > JavaCalls::call_special(&result,
>>>>>>>>>> thread_oop,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Okay, I will upload new webrev
>>>>>>>>>> later.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>> Thanks!
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > The launcher seem to name
>>>>>>>>>> itself
>>>>>>>>>> 'java' and
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> naming
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> this
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> thread
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> just
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > 'main' is confusing to me.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > E.g. so main thread of the
>>>>>>>>>> process
>>>>>>>>>> (and
>>>>>>>>>>  >>> thus
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> the
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> process) is
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> 'java' but
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > first JavaThread is 'main'.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> The native main thread in the
>>>>>>>>>> process
>>>>>>>>>> is not
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> JavaThread.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> It is
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> waiting
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> for ending of Java main thread
>>>>>>>>>> with
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> pthread_join().
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> set_native_thread_name() is for
>>>>>>>>>>  >>> JavaThread. So I
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> think that
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> we do
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> not
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> need to call it for native main
>>>>>>>>>> thread.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > Not sure if we can change it
>>>>>>>>>> anyhow, since
>>>>>>>>>>  >>> we want
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> java and
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> native
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> name to be the same and java thread
>>>>>>>>>> name
>>>>>>>>>> might
>>>>>>>>>>  >>> have
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> some
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> dependents.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > The name is visible in e.g.
>>>>>>>>>> /proc.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > $ ps H -C java -o 'pid tid comm'
>>>>>>>>>> | head -4
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >   PID   TID COMMAND
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >  6423  6423 java
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >  6423  6424 main
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >  6423  6425 GC Thread#0
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > It would be nice with something
>>>>>>>>>> like
>>>>>>>>>> 'Java Main
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Thread'.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> I do not think so.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Native main thread might not be a
>>>>>>>>>> Java
>>>>>>>>>>  >>> launcher - e.g.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Apache
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> commons-daemon, JNI application,
>>>>>>>>>> etc.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> If you want to change native main
>>>>>>>>>> thread
>>>>>>>>>> name,
>>>>>>>>>>  >>> I think
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> that we
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> have to
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> change Java launcher code.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Should I include it in new webrev?
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>> No
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>> Thanks again!
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>> /Robbin
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > Thanks
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> > /Robbin
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >> Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > Thanks!
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > /Robbin
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > On 03/24/2016 03:26 PM,
>>>>>>>>>> Yasumasa
>>>>>>>>>>  >>> Suenaga wrote:
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > Hi all,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > HotSpot for Linux will set
>>>>>>>>>> thread
>>>>>>>>>>  >>> name via
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> pthread_setname_np().
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > However, main thread
>>>>>>>>>> does not
>>>>>>>>>> have it.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > All JavaThread have native
>>>>>>>>>> name,
>>>>>>>>>> and main
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> thread is
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> JavaThread.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > For consistency, main
>>>>>>>>>> thread
>>>>>>>>>> should have
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> native
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> thread
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> name.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > I uploaded a webrev. Could
>>>>>>>>>> you
>>>>>>>>>> review it?
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>> http://cr.openjdk.java.net/~ysuenaga/JDK-8152690/webrev.00/
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > I cannot access JPRT.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > So I need a sponsor.
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > Thanks,
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > > Yasumasa
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>  > >
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>> >>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>  >>>  > >>>>>>>>>>
>>>>>>>>>>  >>>  >
>>>>>>>>>>  >>>
>>>>>>>>>>
>>>>>>>
>>>>>>



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