Re: [dpdk-dev] [PATCH] ethdev: add L2TPv3 header to flow API

["Sexton, Rory" <rory.sexton@intel.com>]

Hi Ori,

> One general question why do we want to support only v3 and not also v2?
l2tpv3 is more widely used as a tunneling protocol hence it's inclusion.
A specific example is the cable industry where DOCSIS cable traffic is encapsulated using depi and uepi protocols which both make use of l2tpv3 session ids.
Directing flows based on l2tpv3 can be very useful in these cases.

Some more comments inline below.

Rory

>> diff --git a/lib/librte_ethdev/rte_flow.h 
>> b/lib/librte_ethdev/rte_flow.h index 452d359a1..5ee055c28 100644
>> --- a/lib/librte_ethdev/rte_flow.h
>> +++ b/lib/librte_ethdev/rte_flow.h
>> @@ -510,6 +510,16 @@ enum rte_flow_item_type {
>>  	 * See struct rte_flow_item_tag.
>>  	 */
>>  	RTE_FLOW_ITEM_TYPE_TAG,
>> +
>> +	/*
>
>Missing *. It should be /**
>

Will correct this in another version of this patch.

>> +/**
>> + * RTE_FLOW_ITEM_TYPE_L2TPV3.
>> + *
>> + * Matches a L2TPv3 header.
>> + */
>> +struct rte_flow_item_l2tpv3 {
>> +	rte_be32_t session_id; /**< Session ID. */ };
>
>Does it make sense that in future we will want to match on the T / L / ver / Ns / Nr?
>
>Please also consider that any change will be ABI / API breakage, which will be allowed only next year. 
>

I don't foresee us wanting to match on any of the other fields, T / L / ver / Ns/ Nr.
The session id would typically be the only field of interest in the l2tpv3 header.