[openib-general] [PATCH v3 0/6] Tranport Neutral Verbs Proposal.

[James Lentini]

On Mon, 7 Aug 2006, Krishna Kumar2 wrote:

> Hi James,
>  
> > Are the rdmav_ versions intended to be generic or are they intended
> > for use with the native communications managers (IB CM and iWARP CM)?
> 
> It is true that the rdmav_ version is generic. But using the rdmav_ 
> routines means knowing the type of transport interface (eg, I need 
> to do ibv_modify_qp, etc). 

Is there a benefit to having rdmav_create_qp() take generic 
parameters if the application needs to understand the type of QP (IB, 
iWARP, etc.) created and the transport specific communication manager 
calls that are needed to manipulate it?

Would it make more sense if the QP create command was also transport 
specific?

> Using CMA makes that invisible as the application does an 
> rdma_create_id, create_qp, bind/listen/connect, etc, and then 
> proceeds to post wr 's to the qp using ibv_post_send(), etc.
> 
> > Is there a way that the differences could be made clearer? Could one 
> > be eliminated?
> 
> If I understand right, the CMA interface was designed and added to 
> let the application use the IB/iwarp devices without knowing the 
> underlying interface. 

Correct.

> So it would not make sense to remove this interface (and definitely 
> not the rdmav_() interfaces as that is used by rdma_() interface).

We should definitely keep both intefaces.