On Sun, Sep 14, 2014 at 11:16 AM, Roadstar Runner <[email protected]>
wrote:

> I have also noticed some strange behavior with ResourceDefaultOwner. If a
> module calls Resource.request() in  Boot.booted(), 
> ResourceDefaultOwner.requested()
> is signaled before the resource is granted to the default owner
>

by default on power up, after initialization, the default owner owns the
resource, by default.   It doesn't actually get granted on the way up.


>
> On Sun, Sep 14, 2014 at 12:59 PM, Eric Decker <[email protected]> wrote:
>
>>
>>
>> On Sun, Sep 14, 2014 at 7:28 AM, Roadstar Runner <[email protected]>
>> wrote:
>>
>>> But if thee is no default owner for the resource, then the system could
>>> be locked because module 2 will never get the resource. I was under the
>>> impression that if a call to Resouce.request() returns SUCCESS , then
>>> either granted or requested will have to be signaled so that the resource
>>> is  actually shared.
>>>
>>
>> It is my understanding that if Resource.request() returns SUCCESS than
>> one is guaranteed that .granted will eventually be signalled.   (Not either
>> .granted or .requested).
>>
>> .requested will only be delivered after a module owns a resource and
>> another module requests the resource.
>>
>> Also if module2 has the resource, releases it and immediately requests it
>>> again before module 1 is granted the resource...we will lock up the system
>>>
>>
>> I have to verify this (currently working on it), but what currently
>> happens (with FCFSArbiter) is Module2 will be granted the resource again.
>> So the system doesn't lock up but the proper behaviour doesn't occur.
>> Queue discipline isn't properly honored.
>>
>>
>> --
>> Eric B. Decker
>> Senior (over 50 :-) Researcher
>>
>>
>


-- 
Eric B. Decker
Senior (over 50 :-) Researcher
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