Re: [dpdk-dev] [PATCH v2 2/3] examples/l3fwd: use IP reserved addresses for EM mode

[David Marchand <david.marchand@redhat.com>]

On Sun, Aug 2, 2020 at 8:17 PM <pbhagavatula@marvell.com> wrote:
>
> From: Pavan Nikhilesh <pbhagavatula@marvell.com>
>
> The l3fwd example should use the reserved IPv4/v6 reserved address
> ranges defined in RFC5735 and RFC5180 and RFC863 discard protocol for
> the port number in the exact match mode of L3 forwarding.
>
> Signed-off-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
> ---
>  examples/l3fwd/l3fwd_em.c | 87 ++++++++++++++++++++++++++-------------
>  1 file changed, 59 insertions(+), 28 deletions(-)

Would such a change affect current users?
If so, please add a release note update.


I see DTS uses l3fwd.
If the change has an impact, probably worth reporting it on the dts ml.


>
> diff --git a/examples/l3fwd/l3fwd_em.c b/examples/l3fwd/l3fwd_em.c
> index fdbee70b4..481b6dcce 100644
> --- a/examples/l3fwd/l3fwd_em.c
> +++ b/examples/l3fwd/l3fwd_em.c
[snip]
> @@ -429,7 +460,7 @@ populate_ipv4_many_flow_into_table(const struct rte_hash *h,
>                 switch (i & (NUMBER_PORT_USED - 1)) {
>                 case 0:
>                         entry = ipv4_l3fwd_em_route_array[0];
> -                       entry.key.ip_dst = RTE_IPV4(101, c, b, a);
> +                       entry.key.ip_dst = RTE_IPV4(9, c, b, a);
>                         break;
>                 case 1:
>                         entry = ipv4_l3fwd_em_route_array[1];
> @@ -437,11 +468,11 @@ populate_ipv4_many_flow_into_table(const struct rte_hash *h,
>                         break;
>                 case 2:
>                         entry = ipv4_l3fwd_em_route_array[2];
> -                       entry.key.ip_dst = RTE_IPV4(111, c, b, a);
> +                       entry.key.ip_dst = RTE_IPV4(91, c, b, a);
>                         break;
>                 case 3:
>                         entry = ipv4_l3fwd_em_route_array[3];
> -                       entry.key.ip_dst = RTE_IPV4(211, c, b, a);
> +                       entry.key.ip_dst = RTE_IPV4(29, c, b, a);
>                         break;
>                 };
>                 convert_ipv4_5tuple(&entry.key, &newkey);

Why such 9, 91, 29 values? Do they have special properties?

-- 
David Marchand