[openib-general][PATCH][kdapl]: evd upcall policy implementation

[Guy German]

Hi,

>> Are you suggesting that enabling the CQ upcall will not trigger the
>> CQ upcall, if completions happened before enabling?
>> I don't think this is the case, but I'm not 100% sure...
> 
> That is my assumption of how it works. This is how other
> verbs APIs have worked in the past.

Please see InfiniHost MT23108 Programmer's Reference Manual
p 102 section 9.4.1

If completions are posted to the CQ (after the reporting of a completion event) but still not consumed by the software,
events will be generated immediately after request for notification is executed. Subscribe for event is implemented by
writing the CQ doorbell with the request notification command to the appropriate UAR page, and passing as a parameter
to the command the consumer index to be polled.

(found by Or G.)

>> As I mentioned before, and regardless to this issue, I still believe
>> that the right order should be:
>>>>  call kDAPL upcall
>>>>  (conditionally) enable CQ upcall
>> We can't have interrupts if the consumer disabled the upcall
>> policy... 
> 
> I agree that we should not request interrupts if the consumer disabled
> the upcall policy.

Guy