[ofa-general] MLX HCA: CQ request notification for multiple completions not implemented?

[Dotan Barak]

Hi.

Yicheng Jia wrote:
>
> Hi Folks,
>
> I'm trying to use CQ Event notification for multiple completions 
> (ARM_N) according to Mellanox Lx III user manual for scatter/gathering 
> RDMA. However I couldn't find it in current MLX driver. It seems to me 
> that only ARM_NEXT and ARM_SOLICIT are implemented. So if there are 
> multiple work requests, I have to use "poll_cq" to synchronously wait 
> until all the requests are done, is it correct? Is there a way to do 
> asynchronous multiple send by subscribing for a ARM_N event?
You are right: the low level drivers of Mellanox devices doesn't support 
ARM-N
(This feature is supported by the devices, but it wasn't implemented in 
the low level drivers).

You are right, in order to read all of the completions you need to use 
poll_cq.

By the way: Do you have you have to create a completion for any WR?
(if you are using one QP, this will maybe solve your problem).

Dotan