In addition, one or more kernel NIC interfaces are allocated for each
of the configured ports according to the command line parameters.
-The code for allocating the kernel NIC interfaces for a specific port is as follows:
-
-.. code-block:: c
-
- static int
- kni_alloc(uint16_t port_id)
- {
- uint8_t i;
- struct rte_kni *kni;
- struct rte_kni_conf conf;
- struct kni_port_params **params = kni_port_params_array;
-
- if (port_id >= RTE_MAX_ETHPORTS || !params[port_id])
- return -1;
-
- params[port_id]->nb_kni = params[port_id]->nb_lcore_k ? params[port_id]->nb_lcore_k : 1;
-
- for (i = 0; i < params[port_id]->nb_kni; i++) {
-
- /* Clear conf at first */
-
- memset(&conf, 0, sizeof(conf));
- if (params[port_id]->nb_lcore_k) {
- snprintf(conf.name, RTE_KNI_NAMESIZE, "vEth%u_%u", port_id, i);
- conf.core_id = params[port_id]->lcore_k[i];
- conf.force_bind = 1;
- } else
- snprintf(conf.name, RTE_KNI_NAMESIZE, "vEth%u", port_id);
- conf.group_id = (uint16_t)port_id;
- conf.mbuf_size = MAX_PACKET_SZ;
-
- /*
- * The first KNI device associated to a port
- * is the master, for multiple kernel thread
- * environment.
- */
-
- if (i == 0) {
- struct rte_kni_ops ops;
- struct rte_eth_dev_info dev_info;
-
- memset(&dev_info, 0, sizeof(dev_info)); rte_eth_dev_info_get(port_id, &dev_info);
-
- conf.addr = dev_info.pci_dev->addr;
- conf.id = dev_info.pci_dev->id;
-
- /* Get the interface default mac address */
- rte_eth_macaddr_get(port_id, (struct ether_addr *)&conf.mac_addr);
-
- memset(&ops, 0, sizeof(ops));
-
- ops.port_id = port_id;
- ops.change_mtu = kni_change_mtu;
- ops.config_network_if = kni_config_network_interface;
- ops.config_mac_address = kni_config_mac_address;
-
- kni = rte_kni_alloc(pktmbuf_pool, &conf, &ops);
- } else
- kni = rte_kni_alloc(pktmbuf_pool, &conf, NULL);
-
- if (!kni)
- rte_exit(EXIT_FAILURE, "Fail to create kni for "
- "port: %d\n", port_id);
-
- params[port_id]->kni[i] = kni;
- }
- return 0;
- }
+The code for allocating the kernel NIC interfaces for a specific port is
+in the function ``kni_alloc``.
The other step in the initialization process that is unique to this sample application
is the association of each port with lcores for RX, TX and kernel threads.
* Other lcores for pinning the kernel threads on one by one
-This is done by using the`kni_port_params_array[]` array, which is indexed by the port ID.
-The code is as follows:
-
-.. code-block:: console
-
- static int
- parse_config(const char *arg)
- {
- const char *p, *p0 = arg;
- char s[256], *end;
- unsigned size;
- enum fieldnames {
- FLD_PORT = 0,
- FLD_LCORE_RX,
- FLD_LCORE_TX,
- _NUM_FLD = KNI_MAX_KTHREAD + 3,
- };
- int i, j, nb_token;
- char *str_fld[_NUM_FLD];
- unsigned long int_fld[_NUM_FLD];
- uint16_t port_id, nb_kni_port_params = 0;
-
- memset(&kni_port_params_array, 0, sizeof(kni_port_params_array));
-
- while (((p = strchr(p0, '(')) != NULL) && nb_kni_port_params < RTE_MAX_ETHPORTS) {
- p++;
- if ((p0 = strchr(p, ')')) == NULL)
- goto fail;
-
- size = p0 - p;
-
- if (size >= sizeof(s)) {
- printf("Invalid config parameters\n");
- goto fail;
- }
-
- snprintf(s, sizeof(s), "%.*s", size, p);
- nb_token = rte_strsplit(s, sizeof(s), str_fld, _NUM_FLD, ',');
-
- if (nb_token <= FLD_LCORE_TX) {
- printf("Invalid config parameters\n");
- goto fail;
- }
-
- for (i = 0; i < nb_token; i++) {
- errno = 0;
- int_fld[i] = strtoul(str_fld[i], &end, 0);
- if (errno != 0 || end == str_fld[i]) {
- printf("Invalid config parameters\n");
- goto fail;
- }
- }
-
- i = 0;
- port_id = (uint8_t)int_fld[i++];
-
- if (port_id >= RTE_MAX_ETHPORTS) {
- printf("Port ID %u could not exceed the maximum %u\n", port_id, RTE_MAX_ETHPORTS);
- goto fail;
- }
-
- if (kni_port_params_array[port_id]) {
- printf("Port %u has been configured\n", port_id);
- goto fail;
- }
-
- kni_port_params_array[port_id] = (struct kni_port_params*)rte_zmalloc("KNI_port_params", sizeof(struct kni_port_params), RTE_CACHE_LINE_SIZE);
- kni_port_params_array[port_id]->port_id = port_id;
- kni_port_params_array[port_id]->lcore_rx = (uint8_t)int_fld[i++];
- kni_port_params_array[port_id]->lcore_tx = (uint8_t)int_fld[i++];
-
- if (kni_port_params_array[port_id]->lcore_rx >= RTE_MAX_LCORE || kni_port_params_array[port_id]->lcore_tx >= RTE_MAX_LCORE) {
- printf("lcore_rx %u or lcore_tx %u ID could not "
- "exceed the maximum %u\n",
- kni_port_params_array[port_id]->lcore_rx, kni_port_params_array[port_id]->lcore_tx, RTE_MAX_LCORE);
- goto fail;
- }
-
- for (j = 0; i < nb_token && j < KNI_MAX_KTHREAD; i++, j++)
- kni_port_params_array[port_id]->lcore_k[j] = (uint8_t)int_fld[i];
- kni_port_params_array[port_id]->nb_lcore_k = j;
- }
-
- print_config();
-
- return 0;
-
- fail:
-
- for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
- if (kni_port_params_array[i]) {
- rte_free(kni_port_params_array[i]);
- kni_port_params_array[i] = NULL;
- }
- }
-
- return -1;
-
- }
+This is done by using the ``kni_port_params_array[]`` array, which is indexed by the port ID.
+The code is in the function ``parse_config``.
Packet Forwarding
~~~~~~~~~~~~~~~~~
This function first checks the lcore_id against the user provided lcore_rx and lcore_tx
to see if this lcore is reading from or writing to kernel NIC interfaces.
-For the case that reads from a NIC port and writes to the kernel NIC interfaces,
+For the case that reads from a NIC port and writes to the kernel NIC interfaces (``kni_ingress``),
the packet reception is the same as in L2 Forwarding sample application
(see :ref:`l2_fwd_app_rx_tx_packets`).
The packet transmission is done by sending mbufs into the kernel NIC interfaces by rte_kni_tx_burst().
The KNI library automatically frees the mbufs after the kernel successfully copied the mbufs.
-.. code-block:: c
-
- /**
- * Interface to burst rx and enqueue mbufs into rx_q
- */
-
- static void
- kni_ingress(struct kni_port_params *p)
- {
- uint8_t i, nb_kni, port_id;
- unsigned nb_rx, num;
- struct rte_mbuf *pkts_burst[PKT_BURST_SZ];
-
- if (p == NULL)
- return;
-
- nb_kni = p->nb_kni;
- port_id = p->port_id;
-
- for (i = 0; i < nb_kni; i++) {
- /* Burst rx from eth */
- nb_rx = rte_eth_rx_burst(port_id, 0, pkts_burst, PKT_BURST_SZ);
- if (unlikely(nb_rx > PKT_BURST_SZ)) {
- RTE_LOG(ERR, APP, "Error receiving from eth\n");
- return;
- }
-
- /* Burst tx to kni */
- num = rte_kni_tx_burst(p->kni[i], pkts_burst, nb_rx);
- kni_stats[port_id].rx_packets += num;
- rte_kni_handle_request(p->kni[i]);
-
- if (unlikely(num < nb_rx)) {
- /* Free mbufs not tx to kni interface */
- kni_burst_free_mbufs(&pkts_burst[num], nb_rx - num);
- kni_stats[port_id].rx_dropped += nb_rx - num;
- }
- }
- }
-
-For the other case that reads from kernel NIC interfaces and writes to a physical NIC port, packets are retrieved by reading
-mbufs from kernel NIC interfaces by `rte_kni_rx_burst()`.
+For the other case that reads from kernel NIC interfaces
+and writes to a physical NIC port (``kni_egress``),
+packets are retrieved by reading mbufs from kernel NIC interfaces by ``rte_kni_rx_burst()``.
The packet transmission is the same as in the L2 Forwarding sample application
(see :ref:`l2_fwd_app_rx_tx_packets`).
-.. code-block:: c
-
- /**
- * Interface to dequeue mbufs from tx_q and burst tx
- */
-
- static void
-
- kni_egress(struct kni_port_params *p)
- {
- uint8_t i, nb_kni, port_id;
- unsigned nb_tx, num;
- struct rte_mbuf *pkts_burst[PKT_BURST_SZ];
-
- if (p == NULL)
- return;
-
- nb_kni = p->nb_kni;
- port_id = p->port_id;
-
- for (i = 0; i < nb_kni; i++) {
- /* Burst rx from kni */
- num = rte_kni_rx_burst(p->kni[i], pkts_burst, PKT_BURST_SZ);
- if (unlikely(num > PKT_BURST_SZ)) {
- RTE_LOG(ERR, APP, "Error receiving from KNI\n");
- return;
- }
-
- /* Burst tx to eth */
-
- nb_tx = rte_eth_tx_burst(port_id, 0, pkts_burst, (uint16_t)num);
-
- kni_stats[port_id].tx_packets += nb_tx;
-
- if (unlikely(nb_tx < num)) {
- /* Free mbufs not tx to NIC */
- kni_burst_free_mbufs(&pkts_burst[nb_tx], num - nb_tx);
- kni_stats[port_id].tx_dropped += num - nb_tx;
- }
- }
- }
-
Callbacks for Kernel Requests
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- ``config_mac_address``
- ``config_promiscusity``
-
-
-.. code-block:: c
-
- static struct rte_kni_ops kni_ops = {
- .change_mtu = kni_change_mtu,
- .config_network_if = kni_config_network_interface,
- .config_mac_address = kni_config_mac_address,
- .config_promiscusity = kni_config_promiscusity,
- };
-
- /* Callback for request of changing MTU */
-
- static int
- kni_change_mtu(uint16_t port_id, unsigned new_mtu)
- {
- int ret;
- struct rte_eth_conf conf;
-
- RTE_LOG(INFO, APP, "Change MTU of port %d to %u\n", port_id, new_mtu);
-
- /* Stop specific port */
-
- rte_eth_dev_stop(port_id);
-
- memcpy(&conf, &port_conf, sizeof(conf));
-
- /* Set new MTU */
-
- if (new_mtu > ETHER_MAX_LEN)
- conf.rxmode.jumbo_frame = 1;
- else
- conf.rxmode.jumbo_frame = 0;
-
- /* mtu + length of header + length of FCS = max pkt length */
-
- conf.rxmode.max_rx_pkt_len = new_mtu + KNI_ENET_HEADER_SIZE + KNI_ENET_FCS_SIZE;
-
- ret = rte_eth_dev_configure(port_id, 1, 1, &conf);
- if (ret < 0) {
- RTE_LOG(ERR, APP, "Fail to reconfigure port %d\n", port_id);
- return ret;
- }
-
- /* Restart specific port */
-
- ret = rte_eth_dev_start(port_id);
- if (ret < 0) {
- RTE_LOG(ERR, APP, "Fail to restart port %d\n", port_id);
- return ret;
- }
-
- return 0;
- }
-
- /* Callback for request of configuring network interface up/down */
-
- static int
- kni_config_network_interface(uint16_t port_id, uint8_t if_up)
- {
- int ret = 0;
-
- RTE_LOG(INFO, APP, "Configure network interface of %d %s\n",
-
- port_id, if_up ? "up" : "down");
-
- if (if_up != 0) {
- /* Configure network interface up */
- rte_eth_dev_stop(port_id);
- ret = rte_eth_dev_start(port_id);
- } else /* Configure network interface down */
- rte_eth_dev_stop(port_id);
-
- if (ret < 0)
- RTE_LOG(ERR, APP, "Failed to start port %d\n", port_id);
- return ret;
- }
-
- /* Callback for request of configuring device mac address */
-
- static int
- kni_config_mac_address(uint16_t port_id, uint8_t mac_addr[])
- {
- .....
- }
-
- /* Callback for request of configuring promiscuous mode */
-
- static int
- kni_config_promiscusity(uint16_t port_id, uint8_t to_on)
- {
- .....
- }
git.droids-corp.org / dpdk.git / commitdiff