Re: [PATCH v1] ethdev: add direction info when creating the transfer table

[Thomas Monjalon <thomas@monjalon.net>]

15/09/2022 09:47, Ivan Malov:
> As I said, match criteria belong in flow pattern. I recognise the
> importance of the problem that you're looking to solve. It's very
> good that you care to address it, but what this patch tries to do
> is to add more match criteria in the form of new attributes with
> rather questionable names... There's a room for improvement.
> 
> When I say that new features should not confuse readers, I mean
> a very basic thing: readers know that match criteria all sit
> in the pattern. And they refer to the pattern item enum in
> the code and in documentation to learn about criteria,
> while "struct rte_flow_attr" is an unusual place from
> which to learn about match criteria.
> 
> > We should get a conclusion and reflect in the commit changes&logs, and it's easy for others to absorb.
> 
> Yes, but before we get to that, perhaps it pays to hear
> more feedback from other reviewers. Thomas? Ori? Andrew?

Sorry I did not read all.
I think the main question is about the use of attributes.
I refer to this commit of Ivan last year which was agreed:

    ethdev: deprecate direction attributes in transfer flows
    
    Attributes "ingress" and "egress" can only apply unambiguosly
    to non-"transfer" flows. In "transfer" flows, the standpoint
    is effectively shifted to the embedded switch. There can be
    many different endpoints connected to the switch, so the
    use of "ingress" / "egress" does not shed light on which
    endpoints precisely can be considered as traffic sources.
    
    Add relevant deprecation notices and suggest the use of precise
    traffic source items (PORT_REPRESENTOR and REPRESENTED_PORT).
    
    Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
    Acked-by: Ori Kam <orika@nvidia.com>
    Acked-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
    Acked-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>

So +1 for using only pattern items as matching criteria.