Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 28 Apr 2021 19:37:11 +0300
From:   Ido Schimmel <idosch@idosch.org>
To:     Pavel Balaev <balaevpa@infotecs.ru>
Cc:     netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        David Ahern <dsahern@kernel.org>,
        Shuah Khan <shuah@kernel.org>,
        Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        Ido Schimmel <idosch@nvidia.com>
Subject: Re: [PATCH v6 net-next 3/3] selftests/net/forwarding: configurable
 seed tests
Message-ID: <YImPN7C/5BXRv6uC@shredder.lan>
References: <YIlWbxO+AFZAFww7@rnd>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <YIlWbxO+AFZAFww7@rnd>
Precedence: bulk

On Wed, Apr 28, 2021 at 03:34:55PM +0300, Pavel Balaev wrote:
> Test equal and different seed values for IPv4/IPv6
> multipath routing.

The test does not follow the usual convention of forwarding tests that
are expected to be run with both veth pairs and loop backed physical
devices. See: tools/testing/selftests/net/forwarding/README (and
existing tests for reference)

This approach allows us to test both the software and hardware data paths.

You can construct a test where you have multiple VRFs instead of
multiple namespaces. These VRFs emulate your hosts and routers. Send
multiple flows from one host and check the distribution across the
multiple paths connecting your two routers. Change the seed, expect a
different distribution. Go back to original seed and expect the original
distribution.