[dpdk-dev] [PATCH v4 5/6] net/ark: generalize meta data between FPGA and PMD

[Ferruh Yigit]

On 3/10/2021 3:02 PM, Ed Czeck wrote:
> On Tue, Mar 9, 2021 at 12:36 PM Ferruh Yigit <ferruh.yigit at intel.com> wrote:
>>
>> On 3/9/2021 4:08 PM, Ed Czeck wrote:
>>> In this commit we generalize the movement of user-specified
>>> meta data between mbufs and FPGA AXIS tuser fields using
>>> user-defined hook functions.
>>>
>>> - Previous use of PMD dynfields are removed
>>> - Hook function added to ark_user_ext
>>> - Add hook function calls in Rx and Tx paths
>>> - Update guide with example of hook function use
>>> - Add release notes
>>>
>>> Signed-off-by: Ed Czeck <ed.czeck at atomicrules.com>
>>> ---
>>> v3:
>>> - split function rename to separate commit
>>>
>>> v4:
>>> - reorder patches renaming before adding
>>
>> <...>
>>
>>> diff --git a/drivers/net/ark/version.map b/drivers/net/ark/version.map
>>> index 954bea679..4a76d1d52 100644
>>> --- a/drivers/net/ark/version.map
>>> +++ b/drivers/net/ark/version.map
>>> @@ -1,10 +1,3 @@
>>>    DPDK_21 {
>>>        local: *;
>>>    };
>>> -
>>> -EXPERIMENTAL {
>>> -     global:
>>> -
>>> -     rte_pmd_ark_tx_userdata_dynfield_offset;
>>> -     rte_pmd_ark_rx_userdata_dynfield_offset;
>>> -};
>>>
>>
>> Since there is no more public APIs by driver, I think it should stop installing
>> the header, and remove it from 'meson.build' file, and remove the header from
>> API documentation, 'doc/api/doxy-api-index.md'.
>>
>> I can see the header needs to be used by the extension developer, but that is
>> still kind of PMD, the public headers are installed for the application developers.
>>
>> Still there is a desire to install the required headers for PMD developers, as
>> far as I know Bruce is working on it, cc'ed. This header can be installed as
>> part of that effort.
>>
>> Thanks,
>> ferruh
> 
> The function prototypes in the header are required by the extension
> developer, hence
> they need to be accessible in an installed file. Placing them in
> rte_pmd-ark.h seems
> like the existing solution. If there is a better location or solution
> for publishing these
> definitions, I have not found it yet. Please advise if I should change
> this in some way.
> 

I slightly remember we had same discussion before.

Installed public headers are for application usage, but for ark PMD the header 
is for the PMD extension development. Currently there is no similar usage or 
requirement.

'rte_pmd-ark.h' seems installed last release because of the public object it had 
for dynamic mbuf, which should be accessed by application. Now since those 
objects are gone and the content of the header is changed, it is not for 
applications anymore, hence I think it shouldn't be installed.

As far as I can see the PMD extensions are very much related to the FPGA 
implementation, so the header is not for everyone to use to develop new code, I 
expect whoever needs the 'rte_pmd-ark.h' should have the source code already, 
instead of using the header from installed system path.

I think overall it is good to add doxygen comments and dpdk prefix to the 
extension symbols, but still they shouldn't be part of the API documentation.