numam-dpdk/examples/kni/main.c

/*-
 *   BSD LICENSE
 *
 *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <inttypes.h>
#include <string.h>
#include <sys/queue.h>
#include <stdarg.h>
#include <errno.h>
#include <getopt.h>

#include <netinet/in.h>
#include <linux/if.h>
#include <linux/if_tun.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <signal.h>

#include <rte_common.h>
#include <rte_log.h>
#include <rte_memory.h>
#include <rte_memcpy.h>
#include <rte_memzone.h>
#include <rte_eal.h>
#include <rte_per_lcore.h>
#include <rte_launch.h>
#include <rte_atomic.h>
#include <rte_lcore.h>
#include <rte_branch_prediction.h>
#include <rte_interrupts.h>
#include <rte_pci.h>
#include <rte_debug.h>
#include <rte_ether.h>
#include <rte_ethdev.h>
#include <rte_log.h>
#include <rte_mempool.h>
#include <rte_mbuf.h>
#include <rte_string_fns.h>
#include <rte_cycles.h>
#include <rte_malloc.h>
#include <rte_kni.h>

/* Macros for printing using RTE_LOG */
#define RTE_LOGTYPE_APP RTE_LOGTYPE_USER1

/* Max size of a single packet */
#define MAX_PACKET_SZ           2048

/* Size of the data buffer in each mbuf */
#define MBUF_DATA_SZ (MAX_PACKET_SZ + RTE_PKTMBUF_HEADROOM)

/* Number of mbufs in mempool that is created */
#define NB_MBUF                 (8192 * 16)

/* How many packets to attempt to read from NIC in one go */
#define PKT_BURST_SZ            32

/* How many objects (mbufs) to keep in per-lcore mempool cache */
#define MEMPOOL_CACHE_SZ        PKT_BURST_SZ

/* Number of RX ring descriptors */
#define NB_RXD                  128

/* Number of TX ring descriptors */
#define NB_TXD                  512

/* Total octets in ethernet header */
#define KNI_ENET_HEADER_SIZE    14

/* Total octets in the FCS */
#define KNI_ENET_FCS_SIZE       4

#define KNI_US_PER_SECOND       1000000
#define KNI_SECOND_PER_DAY      86400

#define KNI_MAX_KTHREAD 32
/*
 * Structure of port parameters
 */
struct kni_port_params {
	uint8_t port_id;/* Port ID */
	unsigned lcore_rx; /* lcore ID for RX */
	unsigned lcore_tx; /* lcore ID for TX */
	uint32_t nb_lcore_k; /* Number of lcores for KNI multi kernel threads */
	uint32_t nb_kni; /* Number of KNI devices to be created */
	unsigned lcore_k[KNI_MAX_KTHREAD]; /* lcore ID list for kthreads */
	struct rte_kni *kni[KNI_MAX_KTHREAD]; /* KNI context pointers */
} __rte_cache_aligned;

static struct kni_port_params *kni_port_params_array[RTE_MAX_ETHPORTS];


/* Options for configuring ethernet port */
static struct rte_eth_conf port_conf = {
	.rxmode = {
		.header_split = 0,      /* Header Split disabled */
		.hw_ip_checksum = 0,    /* IP checksum offload disabled */
		.hw_vlan_filter = 0,    /* VLAN filtering disabled */
		.jumbo_frame = 0,       /* Jumbo Frame Support disabled */
		.hw_strip_crc = 1,      /* CRC stripped by hardware */
	},
	.txmode = {
		.mq_mode = ETH_MQ_TX_NONE,
	},
};

/* Mempool for mbufs */
static struct rte_mempool * pktmbuf_pool = NULL;

/* Mask of enabled ports */
static uint32_t ports_mask = 0;
/* Ports set in promiscuous mode off by default. */
static int promiscuous_on = 0;

/* Structure type for recording kni interface specific stats */
struct kni_interface_stats {
	/* number of pkts received from NIC, and sent to KNI */
	uint64_t rx_packets;

	/* number of pkts received from NIC, but failed to send to KNI */
	uint64_t rx_dropped;

	/* number of pkts received from KNI, and sent to NIC */
	uint64_t tx_packets;

	/* number of pkts received from KNI, but failed to send to NIC */
	uint64_t tx_dropped;
};

/* kni device statistics array */
static struct kni_interface_stats kni_stats[RTE_MAX_ETHPORTS];

static int kni_change_mtu(uint8_t port_id, unsigned new_mtu);
static int kni_config_network_interface(uint8_t port_id, uint8_t if_up);

static rte_atomic32_t kni_stop = RTE_ATOMIC32_INIT(0);

/* Print out statistics on packets handled */
static void
print_stats(void)
{
	uint8_t i;

	printf("\n**KNI example application statistics**\n"
	       "======  ==============  ============  ============  ============  ============\n"
	       " Port    Lcore(RX/TX)    rx_packets    rx_dropped    tx_packets    tx_dropped\n"
	       "------  --------------  ------------  ------------  ------------  ------------\n");
	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
		if (!kni_port_params_array[i])
			continue;

		printf("%7d %10u/%2u %13"PRIu64" %13"PRIu64" %13"PRIu64" "
							"%13"PRIu64"\n", i,
					kni_port_params_array[i]->lcore_rx,
					kni_port_params_array[i]->lcore_tx,
						kni_stats[i].rx_packets,
						kni_stats[i].rx_dropped,
						kni_stats[i].tx_packets,
						kni_stats[i].tx_dropped);
	}
	printf("======  ==============  ============  ============  ============  ============\n");
}

/* Custom handling of signals to handle stats and kni processing */
static void
signal_handler(int signum)
{
	/* When we receive a USR1 signal, print stats */
	if (signum == SIGUSR1) {
		print_stats();
	}

	/* When we receive a USR2 signal, reset stats */
	if (signum == SIGUSR2) {
		memset(&kni_stats, 0, sizeof(kni_stats));
		printf("\n**Statistics have been reset**\n");
		return;
	}

	/* When we receive a RTMIN or SIGINT signal, stop kni processing */
	if (signum == SIGRTMIN || signum == SIGINT){
		printf("SIGRTMIN is received, and the KNI processing is "
							"going to stop\n");
		rte_atomic32_inc(&kni_stop);
		return;
        }
}

static void
kni_burst_free_mbufs(struct rte_mbuf **pkts, unsigned num)
{
	unsigned i;

	if (pkts == NULL)
		return;

	for (i = 0; i < num; i++) {
		rte_pktmbuf_free(pkts[i]);
		pkts[i] = NULL;
	}
}

/**
 * Interface to burst rx and enqueue mbufs into rx_q
 */
static void
kni_ingress(struct kni_port_params *p)
{
	uint8_t i, port_id;
	unsigned nb_rx, num;
	uint32_t nb_kni;
	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;
		}
	}
}

/**
 * Interface to dequeue mbufs from tx_q and burst tx
 */
static void
kni_egress(struct kni_port_params *p)
{
	uint8_t i, port_id;
	unsigned nb_tx, num;
	uint32_t nb_kni;
	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;
		}
	}
}

static int
main_loop(__rte_unused void *arg)
{
	uint8_t i, nb_ports = rte_eth_dev_count();
	int32_t f_stop;
	const unsigned lcore_id = rte_lcore_id();
	enum lcore_rxtx {
		LCORE_NONE,
		LCORE_RX,
		LCORE_TX,
		LCORE_MAX
	};
	enum lcore_rxtx flag = LCORE_NONE;

	for (i = 0; i < nb_ports; i++) {
		if (!kni_port_params_array[i])
			continue;
		if (kni_port_params_array[i]->lcore_rx == (uint8_t)lcore_id) {
			flag = LCORE_RX;
			break;
		} else if (kni_port_params_array[i]->lcore_tx ==
						(uint8_t)lcore_id) {
			flag = LCORE_TX;
			break;
		}
	}

	if (flag == LCORE_RX) {
		RTE_LOG(INFO, APP, "Lcore %u is reading from port %d\n",
					kni_port_params_array[i]->lcore_rx,
					kni_port_params_array[i]->port_id);
		while (1) {
			f_stop = rte_atomic32_read(&kni_stop);
			if (f_stop)
				break;
			kni_ingress(kni_port_params_array[i]);
		}
	} else if (flag == LCORE_TX) {
		RTE_LOG(INFO, APP, "Lcore %u is writing to port %d\n",
					kni_port_params_array[i]->lcore_tx,
					kni_port_params_array[i]->port_id);
		while (1) {
			f_stop = rte_atomic32_read(&kni_stop);
			if (f_stop)
				break;
			kni_egress(kni_port_params_array[i]);
		}
	} else
		RTE_LOG(INFO, APP, "Lcore %u has nothing to do\n", lcore_id);

	return 0;
}

/* Display usage instructions */
static void
print_usage(const char *prgname)
{
	RTE_LOG(INFO, APP, "\nUsage: %s [EAL options] -- -p PORTMASK -P "
		   "[--config (port,lcore_rx,lcore_tx,lcore_kthread...)"
		   "[,(port,lcore_rx,lcore_tx,lcore_kthread...)]]\n"
		   "    -p PORTMASK: hex bitmask of ports to use\n"
		   "    -P : enable promiscuous mode\n"
		   "    --config (port,lcore_rx,lcore_tx,lcore_kthread...): "
		   "port and lcore configurations\n",
	           prgname);
}

/* Convert string to unsigned number. 0 is returned if error occurs */
static uint32_t
parse_unsigned(const char *portmask)
{
	char *end = NULL;
	unsigned long num;

	num = strtoul(portmask, &end, 16);
	if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0'))
		return 0;

	return (uint32_t)num;
}

static void
print_config(void)
{
	uint32_t i, j;
	struct kni_port_params **p = kni_port_params_array;

	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
		if (!p[i])
			continue;
		RTE_LOG(DEBUG, APP, "Port ID: %d\n", p[i]->port_id);
		RTE_LOG(DEBUG, APP, "Rx lcore ID: %u, Tx lcore ID: %u\n",
					p[i]->lcore_rx, p[i]->lcore_tx);
		for (j = 0; j < p[i]->nb_lcore_k; j++)
			RTE_LOG(DEBUG, APP, "Kernel thread lcore ID: %u\n",
							p[i]->lcore_k[j]);
	}
}

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];
	uint8_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 %d could not exceed the maximum %d\n",
						port_id, RTE_MAX_ETHPORTS);
			goto fail;
		}
		if (kni_port_params_array[port_id]) {
			printf("Port %d has been configured\n", port_id);
			goto fail;
		}
		kni_port_params_array[port_id] =
			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,
						(unsigned)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;
}

static int
validate_parameters(uint32_t portmask)
{
	uint32_t i;

	if (!portmask) {
		printf("No port configured in port mask\n");
		return -1;
	}

	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
		if (((portmask & (1 << i)) && !kni_port_params_array[i]) ||
			(!(portmask & (1 << i)) && kni_port_params_array[i]))
			rte_exit(EXIT_FAILURE, "portmask is not consistent "
				"to port ids specified in --config\n");

		if (kni_port_params_array[i] && !rte_lcore_is_enabled(\
			(unsigned)(kni_port_params_array[i]->lcore_rx)))
			rte_exit(EXIT_FAILURE, "lcore id %u for "
					"port %d receiving not enabled\n",
					kni_port_params_array[i]->lcore_rx,
					kni_port_params_array[i]->port_id);

		if (kni_port_params_array[i] && !rte_lcore_is_enabled(\
			(unsigned)(kni_port_params_array[i]->lcore_tx)))
			rte_exit(EXIT_FAILURE, "lcore id %u for "
					"port %d transmitting not enabled\n",
					kni_port_params_array[i]->lcore_tx,
					kni_port_params_array[i]->port_id);

	}

	return 0;
}

#define CMDLINE_OPT_CONFIG  "config"

/* Parse the arguments given in the command line of the application */
static int
parse_args(int argc, char **argv)
{
	int opt, longindex, ret = 0;
	const char *prgname = argv[0];
	static struct option longopts[] = {
		{CMDLINE_OPT_CONFIG, required_argument, NULL, 0},
		{NULL, 0, NULL, 0}
	};

	/* Disable printing messages within getopt() */
	opterr = 0;

	/* Parse command line */
	while ((opt = getopt_long(argc, argv, "p:P", longopts,
						&longindex)) != EOF) {
		switch (opt) {
		case 'p':
			ports_mask = parse_unsigned(optarg);
			break;
		case 'P':
			promiscuous_on = 1;
			break;
		case 0:
			if (!strncmp(longopts[longindex].name,
				     CMDLINE_OPT_CONFIG,
				     sizeof(CMDLINE_OPT_CONFIG))) {
				ret = parse_config(optarg);
				if (ret) {
					printf("Invalid config\n");
					print_usage(prgname);
					return -1;
				}
			}
			break;
		default:
			print_usage(prgname);
			rte_exit(EXIT_FAILURE, "Invalid option specified\n");
		}
	}

	/* Check that options were parsed ok */
	if (validate_parameters(ports_mask) < 0) {
		print_usage(prgname);
		rte_exit(EXIT_FAILURE, "Invalid parameters\n");
	}

	return ret;
}

/* Initialize KNI subsystem */
static void
init_kni(void)
{
	unsigned int num_of_kni_ports = 0, i;
	struct kni_port_params **params = kni_port_params_array;

	/* Calculate the maximum number of KNI interfaces that will be used */
	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
		if (kni_port_params_array[i]) {
			num_of_kni_ports += (params[i]->nb_lcore_k ?
				params[i]->nb_lcore_k : 1);
		}
	}

	/* Invoke rte KNI init to preallocate the ports */
	rte_kni_init(num_of_kni_ports);
}

/* Initialise a single port on an Ethernet device */
static void
init_port(uint8_t port)
{
	int ret;

	/* Initialise device and RX/TX queues */
	RTE_LOG(INFO, APP, "Initialising port %u ...\n", (unsigned)port);
	fflush(stdout);
	ret = rte_eth_dev_configure(port, 1, 1, &port_conf);
	if (ret < 0)
		rte_exit(EXIT_FAILURE, "Could not configure port%u (%d)\n",
		            (unsigned)port, ret);

	ret = rte_eth_rx_queue_setup(port, 0, NB_RXD,
		rte_eth_dev_socket_id(port), NULL, pktmbuf_pool);
	if (ret < 0)
		rte_exit(EXIT_FAILURE, "Could not setup up RX queue for "
				"port%u (%d)\n", (unsigned)port, ret);

	ret = rte_eth_tx_queue_setup(port, 0, NB_TXD,
		rte_eth_dev_socket_id(port), NULL);
	if (ret < 0)
		rte_exit(EXIT_FAILURE, "Could not setup up TX queue for "
				"port%u (%d)\n", (unsigned)port, ret);

	ret = rte_eth_dev_start(port);
	if (ret < 0)
		rte_exit(EXIT_FAILURE, "Could not start port%u (%d)\n",
						(unsigned)port, ret);

	if (promiscuous_on)
		rte_eth_promiscuous_enable(port);
}

/* Check the link status of all ports in up to 9s, and print them finally */
static void
check_all_ports_link_status(uint8_t port_num, uint32_t port_mask)
{
#define CHECK_INTERVAL 100 /* 100ms */
#define MAX_CHECK_TIME 90 /* 9s (90 * 100ms) in total */
	uint8_t portid, count, all_ports_up, print_flag = 0;
	struct rte_eth_link link;

	printf("\nChecking link status\n");
	fflush(stdout);
	for (count = 0; count <= MAX_CHECK_TIME; count++) {
		all_ports_up = 1;
		for (portid = 0; portid < port_num; portid++) {
			if ((port_mask & (1 << portid)) == 0)
				continue;
			memset(&link, 0, sizeof(link));
			rte_eth_link_get_nowait(portid, &link);
			/* print link status if flag set */
			if (print_flag == 1) {
				if (link.link_status)
					printf("Port %d Link Up - speed %u "
						"Mbps - %s\n", (uint8_t)portid,
						(unsigned)link.link_speed,
				(link.link_duplex == ETH_LINK_FULL_DUPLEX) ?
					("full-duplex") : ("half-duplex\n"));
				else
					printf("Port %d Link Down\n",
						(uint8_t)portid);
				continue;
			}
			/* clear all_ports_up flag if any link down */
			if (link.link_status == ETH_LINK_DOWN) {
				all_ports_up = 0;
				break;
			}
		}
		/* after finally printing all link status, get out */
		if (print_flag == 1)
			break;

		if (all_ports_up == 0) {
			printf(".");
			fflush(stdout);
			rte_delay_ms(CHECK_INTERVAL);
		}

		/* set the print_flag if all ports up or timeout */
		if (all_ports_up == 1 || count == (MAX_CHECK_TIME - 1)) {
			print_flag = 1;
			printf("done\n");
		}
	}
}

/* Callback for request of changing MTU */
static int
kni_change_mtu(uint8_t port_id, unsigned new_mtu)
{
	int ret;
	struct rte_eth_conf conf;

	if (port_id >= rte_eth_dev_count()) {
		RTE_LOG(ERR, APP, "Invalid port id %d\n", port_id);
		return -EINVAL;
	}

	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(uint8_t port_id, uint8_t if_up)
{
	int ret = 0;

	if (port_id >= rte_eth_dev_count() || port_id >= RTE_MAX_ETHPORTS) {
		RTE_LOG(ERR, APP, "Invalid port id %d\n", port_id);
		return -EINVAL;
	}

	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;
}

static int
kni_alloc(uint8_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;

			memset(&ops, 0, sizeof(ops));
			ops.port_id = port_id;
			ops.change_mtu = kni_change_mtu;
			ops.config_network_if = kni_config_network_interface;

			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;
}

static int
kni_free_kni(uint8_t port_id)
{
	uint8_t i;
	struct kni_port_params **p = kni_port_params_array;

	if (port_id >= RTE_MAX_ETHPORTS || !p[port_id])
		return -1;

	for (i = 0; i < p[port_id]->nb_kni; i++) {
		if (rte_kni_release(p[port_id]->kni[i]))
			printf("Fail to release kni\n");
		p[port_id]->kni[i] = NULL;
	}
	rte_eth_dev_stop(port_id);

	return 0;
}

/* Initialise ports/queues etc. and start main loop on each core */
int
main(int argc, char** argv)
{
	int ret;
	uint8_t nb_sys_ports, port;
	unsigned i;

	/* Associate signal_hanlder function with USR signals */
	signal(SIGUSR1, signal_handler);
	signal(SIGUSR2, signal_handler);
	signal(SIGRTMIN, signal_handler);
	signal(SIGINT, signal_handler);

	/* Initialise EAL */
	ret = rte_eal_init(argc, argv);
	if (ret < 0)
		rte_exit(EXIT_FAILURE, "Could not initialise EAL (%d)\n", ret);
	argc -= ret;
	argv += ret;

	/* Parse application arguments (after the EAL ones) */
	ret = parse_args(argc, argv);
	if (ret < 0)
		rte_exit(EXIT_FAILURE, "Could not parse input parameters\n");

	/* Create the mbuf pool */
	pktmbuf_pool = rte_pktmbuf_pool_create("mbuf_pool", NB_MBUF,
		MEMPOOL_CACHE_SZ, 0, MBUF_DATA_SZ, rte_socket_id());
	if (pktmbuf_pool == NULL) {
		rte_exit(EXIT_FAILURE, "Could not initialise mbuf pool\n");
		return -1;
	}

	/* Get number of ports found in scan */
	nb_sys_ports = rte_eth_dev_count();
	if (nb_sys_ports == 0)
		rte_exit(EXIT_FAILURE, "No supported Ethernet device found\n");

	/* Check if the configured port ID is valid */
	for (i = 0; i < RTE_MAX_ETHPORTS; i++)
		if (kni_port_params_array[i] && i >= nb_sys_ports)
			rte_exit(EXIT_FAILURE, "Configured invalid "
						"port ID %u\n", i);

	/* Initialize KNI subsystem */
	init_kni();

	/* Initialise each port */
	for (port = 0; port < nb_sys_ports; port++) {
		/* Skip ports that are not enabled */
		if (!(ports_mask & (1 << port)))
			continue;
		init_port(port);

		if (port >= RTE_MAX_ETHPORTS)
			rte_exit(EXIT_FAILURE, "Can not use more than "
				"%d ports for kni\n", RTE_MAX_ETHPORTS);

		kni_alloc(port);
	}
	check_all_ports_link_status(nb_sys_ports, ports_mask);

	/* Launch per-lcore function on every lcore */
	rte_eal_mp_remote_launch(main_loop, NULL, CALL_MASTER);
	RTE_LCORE_FOREACH_SLAVE(i) {
		if (rte_eal_wait_lcore(i) < 0)
			return -1;
	}

	/* Release resources */
	for (port = 0; port < nb_sys_ports; port++) {
		if (!(ports_mask & (1 << port)))
			continue;
		kni_free_kni(port);
	}
#ifdef RTE_LIBRTE_XEN_DOM0
	rte_kni_close();
#endif
	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 0;
}