RFR 8072466: Deadlock when starting MulticastSocket and DatagramSocket

[Ivan Gerasimov]

Thank you Chris for the review!

Sincerely yours,
Ivan

On 07.09.2015 17:39, Chris Hegarty wrote:
> This looks like a nice cleanup, and fix. Thanks Ivan.
>
> -Chris.
>
> On 05/09/15 15:25, Ivan Gerasimov wrote:
>> Hi everyone!
>>
>> The fix didn't bring enough attention back in February for some reason.
>> So, I'd like to re-request a review.
>>
>> I've added a regression test, which reliably reproduces a deadlock on my
>> local Windows 7 machine.
>>
>> BUGURL: https://bugs.openjdk.java.net/browse/JDK-8072466
>> WEBREV: http://cr.openjdk.java.net/~igerasim/8072466/00/webrev/
>>
>> Sincerely yours,
>> Ivan
>>
>> On 17.02.2015 9:54, Ivan Gerasimov wrote:
>>> Can someone help review this fix please?
>>>
>>> Comments/suggestions are welcome!
>>>
>>> Sincerely yours,
>>> Ivan
>>>
>>> On 06.02.2015 20:48, Ivan Gerasimov wrote:
>>>> Hello!
>>>>
>>>> There has been a deadlock in jdk-net code noticed on Windows.
>>>>
>>>> In the bug description there's a stack snippet showing that one of
>>>> the deadlocked threads stuck in the native initialization code of
>>>> DualStackPlainDatagramSocketImpl and the other -- in initializing of
>>>> TwoStacksPlainDatagramSocketImpl.
>>>>
>>>> I suspect that the reason might be due to unordered initialization:
>>>> AbstractPlainDatagramSocketImpl, the parent of both classes above,
>>>> explicitly loads TwoStacksPlainDatagramSocketImpl from the native
>>>> init().
>>>> Thus, when both classes are being initialized concurrently, it may
>>>> end with a clash.
>>>>
>>>>
>>>> Another issue noticed by Mark Sheppard is that the Windows version of
>>>> DefaultDatagramSocketImplFactory.createDatagramSocketImpl() isn't
>>>> synchronized, but reads/modifies shared data.
>>>> Thus, I removed modification and declared all the accessed fields 
>>>> final.
>>>>
>>>> Would you please help review the proposed fix?
>>>>
>>>> BUGURL: https://bugs.openjdk.java.net/browse/JDK-8072466
>>>> WEBREV: http://cr.openjdk.java.net/~igerasim/8072466/0/webrev/
>>>>
>>>> The build went fine on all the platforms, all the tests from
>>>> (net|nio|io) passed Okay.
>>>>
>>>> Sincerely yours,
>>>> Ivan
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>
>