Re: [RFC PATCH 03/16] ib/mad: Add check for jumbo MADs support on a device

[Or Gerlitz <ogerlitz-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>]

On 11/13/2014 9:54 PM, ira.weiny-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org wrote:

> Add a device capability flag for OPA devices to signal their support of "jumbo"
> MADs.
>
> Check for IB_DEVICE_JUMBO_MAD_SUPPORT in the device capabilities and if
> supported mark the special QPs created.

Ira,

Few comments here, the device capability is OK, specifically if it helps 
for the mad
layer logic to be simpler and/or more robust.

You should add device attribute telling what is the size of MADs 
supported by the
device, I think the IBTA mandated 256Band in the OPA case, the driver 
will fill there 2k.

You can't just state that (jumbo == 2k) and go to complete design/changes
which use this hard-coded assumption. You need to see how to re-spin 
this series
w.o this assumption.

I find it very annoying that upper level drivers replicate in different 
ways elements
from the IB device attributes returned by ib_query_device. I met that in 
multiple
drivers and upcoming designs for which I do code review. Are you up to 
come up
with a patch that caches the device attributes on the device structure? 
if not,
I can do that.. and have your code to see it.

Also, I would go and unify (squash) this patch and the preceding one.


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