[9] RFR(S): 8005873: JRuby test_respond_to.rb asserts with: MT-unsafe modification of inline cache

[Tobias Hartmann]

Hi Vladimir,

On 02.06.2014 19:38, Vladimir Ivanov wrote:
> On 6/2/14 9:23 PM, Christian Thalinger wrote:
>>
>> On Jun 2, 2014, at 6:29 AM, Vladimir Ivanov 
>> <vladimir.x.ivanov at oracle.com> wrote:
>>
>>> Tobias, I'll take care of it.
>>
>> Are you also taking care of the backports?
> Yes. I'll backport into 8u myself and for 7 I'll ask help from 
> Sustaining.

Thank you!

Best,
Tobias

>
> Best regards,
> Vladimir Ivanov
>>
>>>
>>> Best regards,
>>> Vladimir Ivanov
>>>
>>> On 6/2/14 10:04 AM, Tobias Hartmann wrote:
>>>>
>>>> On 28.05.2014 12:48, Vladimir Ivanov wrote:
>>>>> Looks good.
>>>>>
>>>>> It should be safe to sync on MTF instance since it's not accessible
>>>>> outside (MTF and MT.form() are package-private).
>>>>>
>>>>> Best regards,
>>>>> Vladimir Ivanov
>>>>
>>>> Thank you, Vladimir.
>>>>
>>>> Could someone please push the patch?
>>>>
>>>> Thanks,
>>>> Tobias
>>>>
>>>>>
>>>>> On 5/28/14 1:49 PM, Tobias Hartmann wrote:
>>>>>> Hi,
>>>>>>
>>>>>> thanks everyone for the feedback!
>>>>>>
>>>>>> @Remi: I agree with Paul. This is not a problem because if the 
>>>>>> normal
>>>>>> read sees an outdated null value, a new LambdaForm is created and
>>>>>> setCachedLambdaForm(...) is executed. This will guarantee that the
>>>>>> non-null value is seen and used. The unnecessary creation of a new
>>>>>> LamdaForm is not a problem either.
>>>>>>
>>>>>> @John: I added the code that you suggested to simulate CAS. 
>>>>>> Please find
>>>>>> the new webrev at:
>>>>>>
>>>>>> http://cr.openjdk.java.net/~anoll/8005873/webrev.02/
>>>>>>
>>>>>> Sorry for the delay, I was on vacation.
>>>>>>
>>>>>> Thanks,
>>>>>> Tobias
>>>>>>
>>>>>> On 19.05.2014 20:31, John Rose wrote:
>>>>>>> On May 16, 2014, at 4:56 AM, Tobias Hartmann
>>>>>>> <tobias.hartmann at oracle.com> wrote:
>>>>>>>
>>>>>>>> Is it sufficient then to use synchronized (lambdaForms) { ... } in
>>>>>>>> setCachedLambdaForm(..) and a normal read in cachedLambdaForm(..)?
>>>>>>> Yes, that is how I see it.  The fast path is a racy non-volatile 
>>>>>>> read
>>>>>>> of a safely-published structure.
>>>>>>>
>>>>>>> (If safe publication via arrays were broken, java.lang.String 
>>>>>>> would be
>>>>>>> broken.  But the JMM is carefully designed to support safe 
>>>>>>> publication
>>>>>>> of array elements, and through array elements.)
>>>>>>>
>>>>>>> — John
>>>>>>
>>>>
>>