RFR: 8158985: [JVMCI] access to HotSpotJVMCIRuntime.vmEventListeners must be thread safe

[Doug Simon]

I should go to bed! ;-)

Fixed in the webrev.

> On 08 Jun 2016, at 01:15, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:
> 
> +                    for (HotSpotVMEventListener vmEventListener : ServiceLoader.load(HotSpotVMEventListener.class)) {
> +                        vmEventListeners.add(vmEventListener);
> 
> should be listeners.add(vmEventListener);
> 
> +                    }
> +                    vmEventListeners = listeners;
> 
> 
> On 6/7/16 4:04 PM, Doug Simon wrote:
>> Thanks for the suggestion - I updated the webrev with the suggested change.
>> 
>>> On 08 Jun 2016, at 00:18, Igor Veresov <igor.veresov at oracle.com> wrote:
>>> 
>>> It seems possible that the callers of getVmEventListeners() would be able to see a partially formed list, right?
>>> May be delay assignment to vmEventListeners until the list is fully formed?
>>> 
>>> igor
>>> 
>>>> On Jun 7, 2016, at 3:03 PM, Doug Simon <doug.simon at oracle.com> wrote:
>>>> 
>>>> https://bugs.openjdk.java.net/browse/JDK-8158985
>>>> http://cr.openjdk.java.net/~dnsimon/8158985/
>>>> 
>>>> -Doug
>>> 
>>