[dpdk-dev] [PATCH] doc: announce flow API matching pattern struct changes

[Ferruh Yigit]

On 11/23/2020 1:50 PM, Andrew Rybchenko wrote:
> On 11/23/20 4:40 PM, Ferruh Yigit wrote:
>> Proposing to replace protocol header fields in the ``rte_flow_item_*``
>> structures with the protocol structs, like:
>>
>> Current ``struct rte_flow_item_eth``,
>>
>> struct rte_flow_item_eth {
>> 	struct rte_ether_addr dst;
>> 	struct rte_ether_addr src;
>> 	rte_be16_t type;
>> 	uint32_t has_vlan:1;
>> 	uint32_t reserved:31;
>> }
>>
>> will become
>>
>> struct rte_flow_item_eth {
>> 	struct rte_ether_hdr hdr;
>> 	uint32_t has_vlan:1;
>> 	uint32_t reserved:31;
>> }
>>
>> This is both for documenting the intention and to be sure
>> ``rte_flow_item_*`` always starts with complete protocol header.
>>
>> Already many ``rte_flow_item_*`` structs implemented to have protocol
>> struct, target is convert all to this usage.
>>
>> Signed-off-by: Ferruh Yigit <ferruh.yigit at intel.com>
> 
> Acked-by: Andrew Rybchenko <andrew.rybchenko at oktetlabs.ru>
> 
> a minor note below
> 
>> ---
>> Cc: Thomas Monjalon <thomas at monjalon.net>
>> Cc: Andrew Rybchenko <andrew.rybchenko at oktetlabs.ru>
>> Cc: Ori Kam <orika at nvidia.com>
>> ---
>>   doc/guides/rel_notes/deprecation.rst | 7 +++++++
>>   1 file changed, 7 insertions(+)
>>
>> diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
>> index 96986fabd598..a2fa0c196472 100644
>> --- a/doc/guides/rel_notes/deprecation.rst
>> +++ b/doc/guides/rel_notes/deprecation.rst
>> @@ -88,6 +88,13 @@ Deprecation Notices
>>     will be limited to maximum 256 queues.
>>     Also compile time flag ``RTE_ETHDEV_QUEUE_STAT_CNTRS`` will be removed.
>>   
>> +* ethdev: The flow API matching pattern structures, ``struct rte_flow_item_*``,
>> +  should start with relevant protocol header.
>> +  Some matching pattern structures implements this by duplicating protocol header
>> +  fields in the struct. To clarify the intention and to be sure protocol header
>> +  is intact, will replace those fields with relevant protocol header struct.
>> +  Target is v21.02 release and this should not change the ABI.
>> +
>>   * sched: To allow more traffic classes, flexible mapping of pipe queues to
>>     traffic classes, and subport level configuration of pipes and queues
>>     changes will be made to macros, data structures and API functions defined
>>
> 
> Just want to highlight that even API could be kept using
> unnamed union for hdr and unnamed structure for existing
> protocol header fields.
> 

Then we may never clean the protocol header fields out of it,
yes this will impact the user but I believe the impact is small and trivial,
I prefer replacing fields with protocol struct.