Re: [PATCH v2 bpf 1/5] net: ethtool: add xdp properties flag set

From: Marek Majtyka <alardam@gmail.com>
To: Jakub Kicinski <kuba@kernel.org>
Cc: "Toke Høiland-Jørgensen" <toke@redhat.com>,
	"Saeed Mahameed" <saeed@kernel.org>,
	"David Ahern" <dsahern@gmail.com>,
	"Maciej Fijalkowski" <maciej.fijalkowski@intel.com>,
	"John Fastabend" <john.fastabend@gmail.com>,
	"Jesper Dangaard Brouer" <jbrouer@redhat.com>,
	"Daniel Borkmann" <daniel@iogearbox.net>,
	"Maciej Fijalkowski" <maciejromanfijalkowski@gmail.com>,
	"Björn Töpel" <bjorn.topel@intel.com>,
	"Andrii Nakryiko" <andrii.nakryiko@gmail.com>,
	"Jonathan Lemon" <jonathan.lemon@gmail.com>,
	"Alexei Starovoitov" <ast@kernel.org>,
	"Network Development" <netdev@vger.kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	hawk@kernel.org, bpf <bpf@vger.kernel.org>,
	intel-wired-lan <intel-wired-lan@lists.osuosl.org>,
	"Karlsson, Magnus" <magnus.karlsson@intel.com>,
	jeffrey.t.kirsher@intel.com
Subject: Re: [PATCH v2 bpf 1/5] net: ethtool: add xdp properties flag set
Date: Wed, 3 Feb 2021 13:50:59 +0100	[thread overview]
Message-ID: <CAAOQfrGqcsn3wu5oxzHYxtE8iK3=gFdTka5HSh5Fe9Hc6HWRWA@mail.gmail.com> (raw)
In-Reply-To: <20210202113456.30cfe21e@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>

On Tue, Feb 2, 2021 at 8:34 PM Jakub Kicinski <kuba@kernel.org> wrote:
>
> On Tue, 02 Feb 2021 13:05:34 +0100 Toke Høiland-Jørgensen wrote:
> > Marek Majtyka <alardam@gmail.com> writes:
> >
> > > Thanks Toke,
> > >
> > > In fact, I was waiting for a single confirmation, disagreement or
> > > comment. I have it now. As there are no more comments, I am getting
> > > down to work right away.
> >
> > Awesome! And sorry for not replying straight away - I hate it when I
> > send out something myself and receive no replies, so I suppose I should
> > get better at not doing that myself :)
> >
> > As for the inclusion of the XDP_BASE / XDP_LIMITED_BASE sets (which I
> > just realised I didn't reply to), I am fine with defining XDP_BASE as a
> > shortcut for TX/ABORTED/PASS/DROP, but think we should skip
> > XDP_LIMITED_BASE and instead require all new drivers to implement the
> > full XDP_BASE set straight away. As long as we're talking about
> > features *implemented* by the driver, at least; i.e., it should still be
> > possible to *deactivate* XDP_TX if you don't want to use the HW
> > resources, but I don't think there's much benefit from defining the
> > LIMITED_BASE set as a shortcut for this mode...
>
> I still have mixed feelings about these flags. The first step IMO
> should be adding validation tests. I bet^W pray every vendor has
> validation tests but since they are not unified we don't know what
> level of interoperability we're achieving in practice. That doesn't
> matter for trivial feature like base actions, but we'll inevitably
> move on to defining more advanced capabilities and the question of
> "what supporting X actually mean" will come up (3 years later, when
> we don't remember ourselves).

I am a bit confused now. Did you mean validation tests of those XDP
flags, which I am working on or some other validation tests?
What should these tests verify? Can you please elaborate more on the
topic, please - just a few sentences how are you see it?