rte flow for arp packet with dpdk - dpdk

Question

Is there a way using rte_flow to send arp and ndp packet to specific rx queue with dpdk
In the rte_flow_item_type I don’t see an entry for arp or ndp
For ipv4 I did the following way
pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH;
pattern[0].spec = NULL;
pattern[1].type = RTE_FLOW_ITEM_TYPE_IPV4;
pattern[1].spec = NULL;
What do i ned to do for arp and ndp? There is no RTE_FLOW_ITEM_TYPE_ARP
Dpdk version: 19.11
NIC: mlx5, 100G mellanox card,

Answer 1

Since v18.05-rc1, there has been item type RTE_FLOW_ITEM_TYPE_ARP_ETH_IPV4. That being said, it might be unsupported by the PMD in question.
Consider matching on the EtherType field instead:
#include <rte_byteorder.h>
#include <rte_ether.h>
#include <rte_flow.h>
struct rte_flow_item_eth item_eth_mask = {};
struct rte_flow_item_eth item_eth_spec = {};
item_eth_spec.hdr.ether_type = RTE_BE16(RTE_ETHER_TYPE_ARP);
item_eth_mask.hdr.ether_type = RTE_BE16(0xFFFF);
pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH;
pattern[0].mask = &item_eth_mask;
pattern[0].spec = &item_eth_spec;
In what comes to NDP, perhaps it pays to check out RTE_FLOW_ITEM_TYPE_ICMP6_ND_*. Again, these might be unsupported by the PMD in question. If that is the case, consider the use of RTE_FLOW_ITEM_TYPE_ICMP6 to redirect all of ICMPv6 to the dedicated queue.

Answer 2

The default queue (with RSS disabled) for no match packet for all vendor PMD are queue 0. Expect for TAP PMD where multiple RX queue is supported by OS.
Since you have mentioned the DPDK version is 19.11, the best option is to make use rte_flow_item_eth to filter desired ether type. That is in DPDK 19.11
struct rte_flow_item_eth {
struct rte_ether_addr dst; /**< Destination MAC. */
struct rte_ether_addr src; /**< Source MAC. */
rte_be16_t type; /**< EtherType or TPID. */
};
so using the following code snippet you can achieve packet type steering to desired queue
struct rte_flow_attr attr = { .ingress = 1 };
struct rte_flow_item pattern[10];
struct rte_flow_action actions[10];
struct rte_flow_action_queue actionqueue = { .index = 1 };
struct rte_flow_item_eth eth;
struct rte_flow_item_vlan vlan;
struct rte_flow_item_ipv4 ipv4;
struct rte_flow *flow;
struct rte_flow_error error;
struct rte_flow_item_eth item_eth_mask;
struct rte_flow_item_eth item_eth_spec;
/* memset item_eth_mask and item_eth_spec to 0 */
item_eth_spec.hdr.ether_type = RTE_BE16(RTE_ETHER_TYPE_ARP);
item_eth_mask.hdr.ether_type = 0xFFFF;
/* setting the eth to pass all packets */
pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH;
pattern[0].spec = ð
pattern[0].last = &item_eth_mask;
pattern[0].mask = &item_eth_spec;
/* end the pattern array */
pattern[1].type = RTE_FLOW_ITEM_TYPE_END;
actions[0].type = RTE_FLOW_ACTION_TYPE_QUEUE;
actions[0].conf = &actionqueue;
actions[1].type = RTE_FLOW_ACTION_TYPE_END;
/* validate and create the flow rule */
if (!rte_flow_validate(port, &attr, pattern, actions, &error))
flow = rte_flow_create(port, &attr, pattern, actions, &error);
else
printf("rte_flow err %s\n", error.message);
note: this fails on Intel X710 and E810 NIC as it support VLAn+IP+UDP|TCP|SCTP+Inner.