Fwd: RFR: 8233375: JFR emergency dump do not recover thread state

[Yasumasa Suenaga]

On 2019/11/04 7:38, David Holmes wrote:
> On 4/11/2019 2:22 am, Markus Gronlund wrote:
>> Hi Yasumasa,
>>
>> I think you can simplify it to something like this:
>>
>> http://cr.openjdk.java.net/~mgronlun/8233375/webrev/
> 
> That is more like I had envisaged for this. Reusing existing thread-state transition code is preferable to adding more custom code that directly manipulates thread-state.

I do not agree with this change.

VMError::report_and_die() has "Thread* thread" in its arguments. So Thread::current() might be different with it.
In addition, ThreadInVMfromUnknown uses transition_from_native() to change the thread state.
It checks (and manipulates?) something which relates to safepoint.

Thus I added ThreadInVMForJFR to new my webrev.


Thanks,

Yasumasa


> Thanks,
> David
> 
>> Thanks
>> Markus
>>
>> -----Original Message-----
>> From: Yasumasa Suenaga <suenaga at oss.nttdata.com>
>> Sent: den 2 november 2019 16:57
>> To: hotspot-jfr-dev at openjdk.java.net; hotspot-runtime-dev at openjdk.java.net
>> Cc: David Holmes <david.holmes at oracle.com>; yasuenag at gmail.com; Markus Gronlund <markus.gronlund at oracle.com>
>> Subject: Re: Fwd: RFR: 8233375: JFR emergency dump do not recover thread state
>>
>> Hi,
>>
>> Markus commented in JBS this change should be kept local to JFR.
>> So I updated webrev. Could you review it?
>>
>>     http://cr.openjdk.java.net/~ysuenaga/JDK-8233375/webrev.01/
>>
>> This change passed all tests on submit repo (mach5-one-ysuenaga-JDK-8233375-1-20191102-1354-6373703).
>>
>>
>> Thanks,
>>
>> Yasumasa
>>
>>
>> On 2019/11/01 18:41, Yasumasa Suenaga wrote:
>>> Forward to hotspot-runtime-dev.
>>>
>>> As David commented in JBS, it may need to be fixed in JFR code.
>>> But I'm not unclear why thread state is not recover.
>>>
>>> I'd like to hear about this from JFR folks.
>>> If it is just a bug in JFR, I will create a patch which recover it in JFR code.
>>>
>>>
>>> Thanks,
>>>
>>> Yasumasa
>>>
>>>
>>> -------- Forwarded Message --------
>>> Subject: RFR: 8233375: JFR emergency dump do not recover thread state
>>> Date: Fri, 1 Nov 2019 17:08:42 +0900
>>> From: Yasumasa Suenaga <suenaga at oss.nttdata.com>
>>> To: hotspot-jfr-dev at openjdk.java.net
>>> CC: yasuenag at gmail.com <yasuenag at gmail.com>
>>>
>>> Hi all,
>>>
>>> Please review this change:
>>>
>>>     JBS: https://bugs.openjdk.java.net/browse/JDK-8233375
>>>     webrev: http://cr.openjdk.java.net/~ysuenaga/JDK-8233375/webrev.00/
>>>
>>> If JFR is running when JVM crashes, JFR will dump data to hs_err_pid<PID>.jfr .
>>> It would perform in prepare_for_emergency_dump().
>>> However this function transits thread state to "_thread_in_vm".
>>>
>>> This change has been tested on submit repo as mach5-one-ysuenaga-JDK-8233375-20191101-0651-6334762.
>>> It failed at compiler/types/correctness/CorrectnessTest.java
>>> However this test is for JIT compiler, and related issue has been reported as JDK-8225620.
>>> So I think this patch can go through.
>>>
>>>
>>> Thanks,
>>>
>>> Yasumasa