[openib-general] Re: [PATCH] [uCM] user specified context in CM events + new test program

[Steve Wooding]

Thanks for clarifying that, Sean.

Cheers,

Steve.

Sean Hefty wrote:

> Steve Wooding wrote:
>
>> I've just starting looking into IB connection establishment and I was 
>> wondering what the ib_cm_init_qp_attr() function actually does. 
>> Studying the MindShare IB book, it talks about exchanging the QPNs, 
>> pSNs etc., via the REQ and REP messages. However, looking at your 
>> cmpost.c example, I see, for exmaple, that in the req handler the 
>> event containing the REQ message is never actually used when modyfing 
>> the QP to RTR. The ib_cm_init_qp_attr() function is used instead. 
>> Does the info in the REQ message get read in kernel space?
>
>
> The kernel CM stores the information used in the establishment of a 
> connection.  It then formats the QP attribute structure for the user.  
> This avoids every app from having to store these same values and 
> format the QP attribute structure.
>
> - Sean
>