Re: [PATCH v4 27/27] IB/Verbs: Cleanup rdma_node_get_transport()

[Tom Tucker <tom@opengridcomputing.com>]

On 4/16/15 8:45 AM, Michael Wang wrote:
>
> On 04/16/2015 03:42 PM, Hal Rosenstock wrote:
>> On 4/16/2015 9:41 AM, Michael Wang wrote:
>>>
>>> On 04/16/2015 03:36 PM, Hal Rosenstock wrote:
>>> [snip]
>>>>> -EXPORT_SYMBOL(rdma_node_get_transport);
>>>>> -
>>>>>   enum rdma_link_layer rdma_port_get_link_layer(struct ib_device *device, u8 port_num)
>>>>>   {
>>>>>   	if (device->get_link_layer)
>>>>> diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
>>>>> index 262bf44..f9ef479 100644
>>>>> --- a/include/rdma/ib_verbs.h
>>>>> +++ b/include/rdma/ib_verbs.h
>>>>> @@ -84,9 +84,6 @@ enum rdma_transport_type {
>>>>>   	RDMA_TRANSPORT_IBOE,
>>>>>   };
>>>>>   
>>>>> -__attribute_const__ enum rdma_transport_type
>>>>> -rdma_node_get_transport(enum rdma_node_type node_type);
>>>>> -
>>>>>   enum rdma_link_layer {
>>>>>   	IB_LINK_LAYER_UNSPECIFIED,
>>>> Is IB_LINK_LAYER_UNSPECIFIED still possible ?
>>> Actually it's impossible in kernel at first, all those who implemented the callback
>>> won't return UNSPECIFIED, others all have the correct transport type (otherwise BUG())
>>> and won't result UNSPECIFIED :-)
>> Should it be removed from this enum somewhere in this patch series
>> (perhaps early on) ?
I don't think it's ever been 'possible.' It's purpose is to catch 
initialized errors where the transport fails to initialize it's 
transport type. So for example,

provider = calloc(1, sizeof *provider)

If 0 is a valid link layer type, then you wouldn't catch these kinds of 
errors.

Tom
> It was still directly used by helper like ib_modify_qp_is_ok() as indicator, may be
> better in another following patch to reform those part :-)
>
> Regards,
> Michael Wang
>
>> -- Hal
>>
>>> Regards,
>>> Michael Wang
>>>
>>>>>   	IB_LINK_LAYER_INFINIBAND,