RFR (S) 8205608: Fix 'frames()' in ThreadReferenceImpl.c to prevent quadratic runtime behavior

[Volker Simonis]

Oh my good!

And I've also forgot to add Ralf as a Contributer :(:(:(

I really desperately need a vacation!

Sorry Ralf,
Volker


On Thu, Jul 26, 2018 at 11:36 AM, Volker Simonis
<volker.simonis at gmail.com> wrote:
> Hi Sergey,
>
> thanks for your help, but I've just pushed the fix now.
>
> @Thomas: sorry, I really apologize, but I've just realized that I've
> forgot to add you as a Reviewer :( I'll promise to look more carefully
> next time.
>
> Regards,
> Volker
>
>
> On Tue, Jul 24, 2018 at 6:01 PM, serguei.spitsyn at oracle.com
> <serguei.spitsyn at oracle.com> wrote:
>> Hi Ralf,
>>
>> I think, you have to consider it reviewed.
>> Sorry, I was not clear no new webrev is needed.
>>
>> Do you need a sponsor for the push?
>>
>> Thanks,
>> Serguei
>>
>>
>>
>> On 7/24/18 06:32, Schmelter, Ralf wrote:
>>>
>>> Hi all,
>>>
>>> here is the update webref with the fixed copyright:
>>> http://cr.openjdk.java.net/~simonis/webrevs/2018/8205608.v5/
>>>
>>> Best regards,
>>> Ralf
>>>
>>> -----Original Message-----
>>> From: serguei.spitsyn at oracle.com [mailto:serguei.spitsyn at oracle.com]
>>> Sent: Freitag, 20. Juli 2018 23:04
>>> To: Chris Plummer <chris.plummer at oracle.com>; Schmelter, Ralf
>>> <ralf.schmelter at sap.com>; serviceability-dev at openjdk.java.net; Stuefe,
>>> Thomas <thomas.stuefe at sap.com>
>>> Subject: Re: RFR (S) 8205608: Fix 'frames()' in ThreadReferenceImpl.c to
>>> prevent quadratic runtime behavior
>>>
>>> On 7/20/18 13:44, Chris Plummer wrote:
>>>>
>>>> On 7/20/18 1:40 PM, serguei.spitsyn at oracle.com wrote:
>>>>>
>>>>> Hi Ralf,
>>>>>
>>>>>
>>>>> On 7/20/18 07:28, Schmelter, Ralf wrote:
>>>>>>
>>>>>> Hi Sergue,
>>>>>>
>>>>>> I’ve updated the webref:
>>>>>> http://cr.openjdk.java.net/~simonis/webrevs/2018/8205608.v4/
>>>>>
>>>>> The copyright year in ThreadReferenceImpl.c still has to be 2018, not
>>>>> 2008.
>>>>>
>>>>>
>>>>> http://cr.openjdk.java.net/~simonis/webrevs/2018/8205608.v4/test/jdk/com/sun/jdi/Frames2Test.java.html
>>>>>
>>>>>
>>>>>    72             if (newDepth == -1_000) {
>>>>>    73                 // Pop some frames so there is room on the stack
>>>>> for the
>>>>>    74                 // call (including println()).
>>>>>    75                 notifyRecursionEnded();
>>>>>    76             }
>>>>>
>>>>>    I have a concern on potential issue mentioned in the comment above.
>>>>>    Should a StackOverflowError be expected here?
>>>>>
>>>>>    79         } catch (StackOverflowError e) {
>>>>>    80             // Use negative depth to indicate the recursion has
>>>>> ended.
>>>>>    81             return -1;
>>>>>    82         }
>>>>>
>>>>>    What is going to happen if the StackOverflowError was really caught
>>>>> above?
>>>>
>>>> The SOE is really caught in the above code. I returns -1, and starts
>>>> the unwinding of the stack. After 1000 frames have been popped via
>>>> returns, notifyRecursionEnded() will be called. The pops are so
>>>> notifyRecursionEnded() can be called without worry of another SOE.
>>>
>>> Got it, thanks Chris.
>>>
>>> So, I'm Okay with the fix assuming the copyright year is fixed.
>>>
>>> Thanks,
>>> Serguei
>>
>>