Re: [PATCH v3 3/3] examples/l3fwd-graph: add IPv6 lookup and rewrite support

[Nithin Dabilpuram <nithind1988@gmail.com>]

Acked-by: Nithin Dabilpuram <ndabilpuram@marvell.com>

On Wed, May 31, 2023 at 5:08 PM Amit Prakash Shukla
<amitprakashs@marvell.com> wrote:
>
> From: Sunil Kumar Kori <skori@marvell.com>
>
> Similar to ipv4, to support IPv6 lookup and rewrite node
> routes and rewrite data needs to be added.
>
> Patch adds routes for ipv6 to validate ip6_lookup node
> and  rewrite data to validate ip6_rewrite node.
>
> Signed-off-by: Sunil Kumar Kori <skori@marvell.com>
> Signed-off-by: Amit Prakash Shukla <amitprakashs@marvell.com>
> ---
> v2:
> - Performance related changes
>
> v3:
> - Removing redundant dynamic variable
>
>  doc/guides/sample_app_ug/l3_forward_graph.rst | 40 ++++++----
>  examples/l3fwd-graph/main.c                   | 77 ++++++++++++++++++-
>  2 files changed, 98 insertions(+), 19 deletions(-)
>
> diff --git a/doc/guides/sample_app_ug/l3_forward_graph.rst b/doc/guides/sample_app_ug/l3_forward_graph.rst
> index 585ac8c898..23f86e4785 100644
> --- a/doc/guides/sample_app_ug/l3_forward_graph.rst
> +++ b/doc/guides/sample_app_ug/l3_forward_graph.rst
> @@ -12,7 +12,8 @@ Overview
>  --------
>
>  The application demonstrates the use of the graph framework and graph nodes
> -``ethdev_rx``, ``ip4_lookup``, ``ip4_rewrite``, ``ethdev_tx`` and ``pkt_drop`` in DPDK to
> +``ethdev_rx``, ``pkt_cls``, ``ip4_lookup``/``ip6_lookup``,
> +``ip4_rewrite``/``ip6_rewrite``, ``ethdev_tx`` and ``pkt_drop`` in DPDK to
>  implement packet forwarding.
>
>  The initialization is very similar to those of the :doc:`l3_forward`.
> @@ -24,13 +25,15 @@ TTL update and finally Tx is implemented inside graph nodes. These nodes are
>  interconnected in graph framework. Application main loop needs to walk over
>  graph using ``rte_graph_walk()`` with graph objects created one per worker lcore.
>
> -The lookup method is as per implementation of ``ip4_lookup`` graph node.
> +The lookup method is as per implementation of ``ip4_lookup``/``ip6_lookup`` graph node.
>  The ID of the output interface for the input packet is the next hop returned by
>  the LPM lookup. The set of LPM rules used by the application is statically
> -configured and provided to ``ip4_lookup`` graph node and ``ip4_rewrite`` graph node
> -using node control API ``rte_node_ip4_route_add()`` and ``rte_node_ip4_rewrite_add()``.
> +configured and provided to ``ip4_lookup``/``ip6_lookup`` graph node and
> +``ip4_rewrite``/``ip6_rewrite`` graph node using node control API
> +``rte_node_ip4_route_add()``/``rte_node_ip6_route_add`` and
> +``rte_node_ip4_rewrite_add()``/``rte_node_ip6_rewrite_add``.
>
> -In the sample application, only IPv4 forwarding is supported as of now.
> +In the sample application, IPv4 and IPv6 forwarding is supported.
>
>  Compiling the Application
>  -------------------------
> @@ -149,8 +152,8 @@ lead to the clone of ``ethdev_rx`` and ``ethdev_tx`` nodes as ``ethdev_rx-X-Y``
>  In case of ``ethdev_tx-X`` nodes, tx queue id assigned per instance of the node
>  is same as graph id.
>
> -These cloned nodes along with existing static nodes such as ``ip4_lookup`` and
> -``ip4_rewrite`` will be used in graph creation to associate node's to lcore
> +These cloned nodes along with existing static nodes such as ``ip4_lookup``/``ip6_lookup``
> +and ``ip4_rewrite``/``ip6_rewrite`` will be used in graph creation to associate node's to lcore
>  specific graph object.
>
>  .. literalinclude:: ../../../examples/l3fwd-graph/main.c
> @@ -186,20 +189,21 @@ Forwarding data(Route, Next-Hop) addition
>  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
>  Once graph objects are created, node specific info like routes and rewrite
> -headers will be provided run-time using ``rte_node_ip4_route_add()`` and
> -``rte_node_ip4_rewrite_add()`` API.
> +headers will be provided run-time using ``rte_node_ip4_route_add()``/
> +``rte_node_ip6_route_add`` and ``rte_node_ip4_rewrite_add()``/``rte_node_ip6_rewrite_add``
> +API.
>
>  .. note::
>
> -    Since currently ``ip4_lookup`` and ``ip4_rewrite`` nodes don't support
> -    lock-less mechanisms(RCU, etc) to add run-time forwarding data like route and
> -    rewrite data, forwarding data is added before packet processing loop is
> -    launched on worker lcore.
> +    Since currently ``ip4_lookup``/``ip6_lookup`` and ``ip4_rewrite``/``ip6_rewrite``
> +    nodes don't support lock-less mechanisms(RCU, etc) to add run-time forwarding
> +    data like route and rewrite data, forwarding data is added before packet
> +    processing loop is launched on worker lcore.
>
>  .. literalinclude:: ../../../examples/l3fwd-graph/main.c
>      :language: c
> -    :start-after: Add route to ip4 graph infra. 8<
> -    :end-before: >8 End of adding route to ip4 graph infa.
> +    :start-after: Add routes and rewrite data to graph infra. 8<
> +    :end-before: >8 End of adding routes and rewrite data to graph infa.
>      :dedent: 1
>
>  Packet Forwarding using Graph Walk
> @@ -215,8 +219,10 @@ specific graph object that was already created.
>
>      rte_graph_walk() will walk over all the sources nodes i.e ``ethdev_rx-X-Y``
>      associated with a given graph and Rx the available packets and enqueue them
> -    to the following node ``ip4_lookup`` which then will enqueue them to ``ip4_rewrite``
> -    node if LPM lookup succeeds. ``ip4_rewrite`` node then will update Ethernet header
> +    to the following node ``pkt_cls`` which based on the packet type will enqueue
> +    them to ``ip4_lookup``/``ip6_lookup`` which then will enqueue them to
> +    ``ip4_rewrite``/``ip6_rewrite`` node if LPM lookup succeeds.
> +    ``ip4_rewrite``/``ip6_rewrite`` node then will update Ethernet header
>      as per next-hop data and transmit the packet via port 'Z' by enqueuing
>      to ``ethdev_tx-Z`` node instance in its graph object.
>
> diff --git a/examples/l3fwd-graph/main.c b/examples/l3fwd-graph/main.c
> index 5feeab4f0f..0c82e24513 100644
> --- a/examples/l3fwd-graph/main.c
> +++ b/examples/l3fwd-graph/main.c
> @@ -27,9 +27,11 @@
>  #include <rte_launch.h>
>  #include <rte_lcore.h>
>  #include <rte_log.h>
> +#include <rte_lpm6.h>
>  #include <rte_mempool.h>
>  #include <rte_node_eth_api.h>
>  #include <rte_node_ip4_api.h>
> +#include <rte_node_ip6_api.h>
>  #include <rte_per_lcore.h>
>  #include <rte_string_fns.h>
>  #include <rte_vect.h>
> @@ -142,6 +144,12 @@ struct ipv4_l3fwd_lpm_route {
>         uint8_t if_out;
>  };
>
> +struct ipv6_l3fwd_lpm_route {
> +       uint8_t ip[RTE_LPM6_IPV6_ADDR_SIZE];
> +       uint8_t depth;
> +       uint8_t if_out;
> +};
> +
>  #define IPV4_L3FWD_LPM_NUM_ROUTES                                              \
>         (sizeof(ipv4_l3fwd_lpm_route_array) /                                  \
>          sizeof(ipv4_l3fwd_lpm_route_array[0]))
> @@ -153,6 +161,28 @@ static struct ipv4_l3fwd_lpm_route ipv4_l3fwd_lpm_route_array[] = {
>         {RTE_IPV4(198, 18, 6, 0), 24, 6}, {RTE_IPV4(198, 18, 7, 0), 24, 7},
>  };
>
> +#define IPV6_L3FWD_LPM_NUM_ROUTES                                              \
> +       (sizeof(ipv6_l3fwd_lpm_route_array) /                                  \
> +        sizeof(ipv6_l3fwd_lpm_route_array[0]))
> +static struct ipv6_l3fwd_lpm_route ipv6_l3fwd_lpm_route_array[] = {
> +       {{0x20, 0x01, 0xdb, 0x08, 0x12, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +       0x00}, 48, 0},
> +       {{0x20, 0x01, 0xdb, 0x08, 0x12, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +       0x01}, 48, 1},
> +       {{0x20, 0x01, 0xdb, 0x08, 0x12, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +       0x02}, 48, 2},
> +       {{0x20, 0x01, 0xdb, 0x08, 0x12, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +       0x03}, 48, 3},
> +       {{0x20, 0x01, 0xdb, 0x08, 0x12, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +       0x04}, 48, 4},
> +       {{0x20, 0x01, 0xdb, 0x08, 0x12, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +       0x05}, 48, 5},
> +       {{0x20, 0x01, 0xdb, 0x08, 0x12, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +       0x06}, 48, 6},
> +       {{0x20, 0x01, 0xdb, 0x08, 0x12, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> +       0x02}, 48, 7},
> +};
> +
>  static int
>  check_lcore_params(void)
>  {
> @@ -1128,7 +1158,7 @@ main(int argc, char **argv)
>         memset(&rewrite_data, 0, sizeof(rewrite_data));
>         rewrite_len = sizeof(rewrite_data);
>
> -       /* Add route to ip4 graph infra. 8< */
> +       /* Add routes and rewrite data to graph infra. 8< */
>         for (i = 0; i < IPV4_L3FWD_LPM_NUM_ROUTES; i++) {
>                 char route_str[INET6_ADDRSTRLEN * 4];
>                 char abuf[INET6_ADDRSTRLEN];
> @@ -1172,7 +1202,50 @@ main(int argc, char **argv)
>                 RTE_LOG(INFO, L3FWD_GRAPH, "Added route %s, next_hop %u\n",
>                         route_str, i);
>         }
> -       /* >8 End of adding route to ip4 graph infa. */
> +
> +       for (i = 0; i < IPV6_L3FWD_LPM_NUM_ROUTES; i++) {
> +               char route_str[INET6_ADDRSTRLEN * 4];
> +               char abuf[INET6_ADDRSTRLEN];
> +               struct in6_addr in6;
> +               uint32_t dst_port;
> +
> +               /* Skip unused ports */
> +               if ((1 << ipv6_l3fwd_lpm_route_array[i].if_out &
> +                    enabled_port_mask) == 0)
> +                       continue;
> +
> +               dst_port = ipv6_l3fwd_lpm_route_array[i].if_out;
> +
> +               memcpy(in6.s6_addr, ipv6_l3fwd_lpm_route_array[i].ip, RTE_LPM6_IPV6_ADDR_SIZE);
> +               snprintf(route_str, sizeof(route_str), "%s / %d (%d)",
> +                        inet_ntop(AF_INET6, &in6, abuf, sizeof(abuf)),
> +                        ipv6_l3fwd_lpm_route_array[i].depth,
> +                        ipv6_l3fwd_lpm_route_array[i].if_out);
> +
> +               /* Use route index 'i' as next hop id */
> +               ret = rte_node_ip6_route_add(ipv6_l3fwd_lpm_route_array[i].ip,
> +                       ipv6_l3fwd_lpm_route_array[i].depth, i,
> +                       RTE_NODE_IP6_LOOKUP_NEXT_REWRITE);
> +
> +               if (ret < 0)
> +                       rte_exit(EXIT_FAILURE,
> +                                "Unable to add ip6 route %s to graph\n",
> +                                route_str);
> +
> +               memcpy(rewrite_data, val_eth + dst_port, rewrite_len);
> +
> +               /* Add next hop rewrite data for id 'i' */
> +               ret = rte_node_ip6_rewrite_add(i, rewrite_data,
> +                                              rewrite_len, dst_port);
> +               if (ret < 0)
> +                       rte_exit(EXIT_FAILURE,
> +                                "Unable to add next hop %u for "
> +                                "route %s\n", i, route_str);
> +
> +               RTE_LOG(INFO, L3FWD_GRAPH, "Added route %s, next_hop %u\n",
> +                       route_str, i);
> +       }
> +       /* >8 End of adding routes and rewrite data to graph infa. */
>
>         /* Launch per-lcore init on every worker lcore */
>         rte_eal_mp_remote_launch(graph_main_loop, NULL, SKIP_MAIN);
> --
> 2.25.1
>