Re: [net-next PATCH v1 01/11] net: flow_table: create interface for hw match/action tables

[Scott Feldman <sfeldma@gmail.com>]

On Mon, Jan 5, 2015 at 10:04 PM, John Fastabend
<john.fastabend@gmail.com> wrote:

>>> + * @uid unique identifier for table
>>> + * @source uid of parent table
>>
>>
>> Is parent table the table previous in the pipeline?  If so, what if
>> you can get to table from N different parent tables, what goes in
>> source?
>
>
> No, you can get the layout of tables from the table graph ops.
>
> Source is used when a single tcam or other implementation mechanism
> is sliced into a set of tables. The current rocker world doesn't use
> this very much at the moment because its static and I just assumed
> every table came out of the same virtual hardware namespace.
>
> A simple example world would be to come up with a set of large virtual
> TCAMs. Any given TCAM maybe sliced into a set of tables. Users may
> organize these either via some out of band configuration at init or
> power on time. In the rocker case we could specify this when we load
> qemu. For now it is just informational. But if we start allowing users
> to create delete tables at runtime it is important to "know" where the
> slices are being allocated/free'd from. The source gives you this
> information.
>
> The hardware devices I'm working on have multiple sources we can
> allocate/free tables from. The source values would provide a way to
> track down which tables are in which hardware namespaces.
>
> Hope that helps?

Got it, thanks.

Can source be encoded in tbl_id?


>> hdr or header?  pick one, probably hdr.
>
>
> hdr is shorter and doesn't lose any clarity IMO I'll use net_flow_hdr
> and net_flow_hdr_node
>
>>
>>> +       struct net_flow_tbl_node **(*ndo_flow_get_tbl_graph)(struct
>>> net_device *dev);
>>
>>
>> move this up next to get_tables
>
>
> sure also what do you think tbl instead of table.

+1 for tbl.