[dpdk-dev] [PATCH v5] distributor_app: new sample app

[reshmapa <reshma.pattan@intel.com>]

From: Reshma Pattan <reshma.pattan@intel.com>

A new sample app that shows the usage of the distributor library. This
app works as follows:

* An RX thread runs which pulls packets from each ethernet port in turn
  and passes those packets to worker using a distributor component.
* The workers take the packets in turn, and determine the output port
  for those packets using basic l2forwarding doing an xor on the source
  port id.
* The RX thread takes the returned packets from the workers and enqueue
  those packets into an rte_ring structure.
* A TX thread pulls the packets off the rte_ring structure and then
  sends each packet out the output port specified previously by the worker
* Command-line option support provided only for portmask.

v5 change:
* Handled gracefull shutdown of rx and tx threads upon SIGINT.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Signed-off-by: Reshma Pattan <reshma.pattan@intel.com>
---
 examples/Makefile                 |    1 +
 examples/distributor_app/Makefile |   57 ++++
 examples/distributor_app/main.c   |  600 +++++++++++++++++++++++++++++++++++++
 examples/distributor_app/main.h   |   46 +++
 4 files changed, 704 insertions(+), 0 deletions(-)
 create mode 100644 examples/distributor_app/Makefile
 create mode 100644 examples/distributor_app/main.c
 create mode 100644 examples/distributor_app/main.h

diff --git a/examples/Makefile b/examples/Makefile
index 6245f83..2ba82b0 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -66,5 +66,6 @@ DIRS-y += vhost
 DIRS-$(CONFIG_RTE_LIBRTE_XEN_DOM0) += vhost_xen
 DIRS-y += vmdq
 DIRS-y += vmdq_dcb
+DIRS-$(CONFIG_RTE_LIBRTE_DISTRIBUTOR) += distributor_app
 
 include $(RTE_SDK)/mk/rte.extsubdir.mk
diff --git a/examples/distributor_app/Makefile b/examples/distributor_app/Makefile
new file mode 100644
index 0000000..6a5bada
--- /dev/null
+++ b/examples/distributor_app/Makefile
@@ -0,0 +1,57 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+#   All rights reserved.
+#
+#   Redistribution and use in source and binary forms, with or without
+#   modification, are permitted provided that the following conditions
+#   are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in
+#       the documentation and/or other materials provided with the
+#       distribution.
+#     * Neither the name of Intel Corporation nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+#   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+#   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+#   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+#   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+#   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+#   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+#   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+#   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+#   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ifeq ($(RTE_SDK),)
+$(error "Please define RTE_SDK environment variable")
+endif
+
+# Default target, can be overriden by command line or environment
+RTE_TARGET ?= x86_64-native-linuxapp-gcc
+
+include $(RTE_SDK)/mk/rte.vars.mk
+
+# binary name
+APP = distributor_app
+
+# all source are stored in SRCS-y
+SRCS-y := main.c
+
+CFLAGS += $(WERROR_FLAGS)
+
+# workaround for a gcc bug with noreturn attribute
+# http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12603
+ifeq ($(CONFIG_RTE_TOOLCHAIN_GCC),y)
+CFLAGS_main.o += -Wno-return-type
+endif
+
+EXTRA_CFLAGS += -O3 -Wfatal-errors
+
+include $(RTE_SDK)/mk/rte.extapp.mk
diff --git a/examples/distributor_app/main.c b/examples/distributor_app/main.c
new file mode 100644
index 0000000..b6fa063
--- /dev/null
+++ b/examples/distributor_app/main.c
@@ -0,0 +1,600 @@
+/*-
+ *   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 <stdint.h>
+#include <inttypes.h>
+#include <unistd.h>
+#include <signal.h>
+#include <getopt.h>
+
+#include <rte_eal.h>
+#include <rte_ethdev.h>
+#include <rte_cycles.h>
+#include <rte_malloc.h>
+#include <rte_debug.h>
+#include <rte_distributor.h>
+
+#include "main.h"
+
+#define RX_RING_SIZE 256
+#define RX_FREE_THRESH 32
+#define RX_PTHRESH 8
+#define RX_HTHRESH 8
+#define RX_WTHRESH 0
+
+#define TX_RING_SIZE 512
+#define TX_FREE_THRESH 32
+#define TX_PTHRESH 32
+#define TX_HTHRESH 0
+#define TX_WTHRESH 0
+#define TX_RSBIT_THRESH 32
+#define TX_Q_FLAGS (ETH_TXQ_FLAGS_NOMULTSEGS | ETH_TXQ_FLAGS_NOVLANOFFL |\
+	ETH_TXQ_FLAGS_NOXSUMSCTP | ETH_TXQ_FLAGS_NOXSUMUDP | \
+	ETH_TXQ_FLAGS_NOXSUMTCP)
+
+#define NUM_MBUFS ((64*1024)-1)
+#define MBUF_SIZE (2048 + sizeof(struct rte_mbuf) + RTE_PKTMBUF_HEADROOM)
+#define MBUF_CACHE_SIZE 250
+#define BURST_SIZE 32
+#define RTE_RING_SZ 1024
+
+/* uncommnet below line to enable debug logs */
+/* #define DEBUG */
+
+#ifdef DEBUG
+#define LOG_LEVEL RTE_LOG_DEBUG
+#define LOG_DEBUG(log_type, fmt, args...) do {	\
+	RTE_LOG(DEBUG, log_type, fmt, ##args)		\
+} while (0)
+#else
+#define LOG_LEVEL RTE_LOG_INFO
+#define LOG_DEBUG(log_type, fmt, args...) do {} while (0)
+#endif
+
+#define RTE_LOGTYPE_DISTRAPP RTE_LOGTYPE_USER1
+
+/* mask of enabled ports */
+static uint32_t enabled_port_mask = 0;
+volatile uint8_t quit_signal = 0;
+
+static volatile struct app_stats {
+	struct {
+		uint64_t rx_pkts;
+		uint64_t returned_pkts;
+		uint64_t enqueued_pkts;
+	} rx __rte_cache_aligned;
+
+	struct {
+		uint64_t dequeue_pkts;
+		uint64_t tx_pkts;
+	} tx __rte_cache_aligned;
+} app_stats;
+
+static const struct rte_eth_conf port_conf_default = {
+	.rxmode = {
+		.mq_mode = ETH_MQ_RX_RSS,
+		.max_rx_pkt_len = ETHER_MAX_LEN,
+		.split_hdr_size = 0,
+		.header_split   = 0, /**< Header Split disabled */
+		.hw_ip_checksum = 0, /**< IP checksum offload enabled */
+		.hw_vlan_filter = 0, /**< VLAN filtering disabled */
+		.jumbo_frame    = 0, /**< Jumbo Frame Support disabled */
+		.hw_strip_crc   = 0, /**< CRC stripped by hardware */
+	},
+	.txmode = {
+		.mq_mode = ETH_MQ_TX_NONE,
+	},
+	.lpbk_mode = 0,
+	.rx_adv_conf = {
+			.rss_conf = {
+				.rss_hf = ETH_RSS_IPV4 | ETH_RSS_IPV6 |
+					ETH_RSS_IPV4_TCP | ETH_RSS_IPV4_UDP |
+					ETH_RSS_IPV6_TCP | ETH_RSS_IPV6_UDP,
+			}
+	},
+};
+
+static const struct rte_eth_rxconf rx_conf_default = {
+	.rx_thresh = {
+		.pthresh = RX_PTHRESH,
+		.hthresh = RX_HTHRESH,
+		.wthresh = RX_WTHRESH,
+	},
+	.rx_free_thresh = RX_FREE_THRESH,
+	.rx_drop_en = 0,
+};
+
+static const struct rte_eth_txconf tx_conf_default = {
+	.tx_thresh = {
+		.pthresh = TX_PTHRESH,
+		.hthresh = TX_HTHRESH,
+		.wthresh = TX_WTHRESH,
+	},
+	.tx_free_thresh = TX_FREE_THRESH,
+	.tx_rs_thresh = TX_RSBIT_THRESH,
+	.txq_flags = TX_Q_FLAGS
+
+};
+
+struct output_buffer {
+	unsigned count;
+	struct rte_mbuf *mbufs[BURST_SIZE];
+};
+
+/*
+ * Initialises a given port using global settings and with the rx buffers
+ * coming from the mbuf_pool passed as parameter
+ */
+static inline int
+port_init(uint8_t port, struct rte_mempool *mbuf_pool)
+{
+	struct rte_eth_conf port_conf = port_conf_default;
+	const uint16_t rxRings = 1, txRings = rte_lcore_count() - 1;
+	int retval;
+	uint16_t q;
+
+	if (port >= rte_eth_dev_count())
+		return -1;
+
+	retval = rte_eth_dev_configure(port, rxRings, txRings, &port_conf);
+	if (retval != 0)
+		return retval;
+
+	for (q = 0; q < rxRings; q++) {
+		retval = rte_eth_rx_queue_setup(port, q, RX_RING_SIZE,
+						rte_eth_dev_socket_id(port),
+						&rx_conf_default, mbuf_pool);
+		if (retval < 0)
+			return retval;
+	}
+
+	for (q = 0; q < txRings; q++) {
+		retval = rte_eth_tx_queue_setup(port, q, TX_RING_SIZE,
+						rte_eth_dev_socket_id(port),
+						&tx_conf_default);
+		if (retval < 0)
+			return retval;
+	}
+
+	retval  = rte_eth_dev_start(port);
+	if (retval < 0)
+		return retval;
+
+	struct rte_eth_link link;
+	rte_eth_link_get_nowait(port, &link);
+	if (!link.link_status) {
+		sleep(1);
+		rte_eth_link_get_nowait(port, &link);
+	}
+
+	if (!link.link_status) {
+		printf("Link down on port %"PRIu8"\n", port);
+		return 0;
+	}
+
+	struct ether_addr addr;
+	rte_eth_macaddr_get(port, &addr);
+	printf("Port %u MAC: %02"PRIx8" %02"PRIx8" %02"PRIx8
+			" %02"PRIx8" %02"PRIx8" %02"PRIx8"\n",
+			(unsigned)port,
+			addr.addr_bytes[0], addr.addr_bytes[1],
+			addr.addr_bytes[2], addr.addr_bytes[3],
+			addr.addr_bytes[4], addr.addr_bytes[5]);
+
+	rte_eth_promiscuous_enable(port);
+
+	return 0;
+}
+
+struct lcore_params {
+	unsigned worker_id;
+	struct rte_distributor *d;
+	struct rte_ring *r;
+};
+
+static int
+lcore_rx(struct lcore_params *p)
+{
+	struct rte_distributor *d = p->d;
+	struct rte_ring *r = p->r;
+	const uint8_t nb_ports = rte_eth_dev_count();
+	const int socket_id = rte_socket_id();
+	uint8_t port;
+
+	for (port = 0; port < nb_ports; port++) {
+		/* skip ports that are not enabled */
+		if ((enabled_port_mask & (1 << port)) == 0)
+			continue;
+
+		if (rte_eth_dev_socket_id(port) > 0 &&
+				rte_eth_dev_socket_id(port) != socket_id)
+			printf("WARNING, port %u is on remote NUMA node to "
+					"RX thread.\n\tPerformance will not "
+					"be optimal.\n", port);
+	}
+
+	printf("\nCore %u doing packet RX.\n", rte_lcore_id());
+	port = 0;
+	while (!quit_signal) {
+		/* skip ports that are not enabled */
+		if ((enabled_port_mask & (1 << port)) == 0) {
+			if (++port == nb_ports)
+				port = 0;
+			continue;
+		}
+		struct rte_mbuf *bufs[BURST_SIZE*2];
+		const uint16_t nb_rx = rte_eth_rx_burst(port, 0, bufs,
+				BURST_SIZE);
+		app_stats.rx.rx_pkts += nb_rx;
+
+		rte_distributor_process(d, bufs, nb_rx);
+		const uint16_t nb_ret = rte_distributor_returned_pkts(d,
+				bufs, BURST_SIZE*2);
+		app_stats.rx.returned_pkts += nb_ret;
+		if (unlikely(nb_ret == 0))
+			continue;
+
+		uint16_t sent = rte_ring_enqueue_burst(r, (void *)bufs, nb_ret);
+		app_stats.rx.enqueued_pkts += sent;
+		if (unlikely(sent < nb_ret)) {
+			LOG_DEBUG(DISTRAPP, "%s:Packet loss due to full ring\n", __func__);
+			while (sent < nb_ret)
+				rte_pktmbuf_free(bufs[sent++]);
+		}
+		if (++port == nb_ports)
+			port = 0;
+	}
+}
+
+static inline void
+flush_one_port(struct output_buffer *outbuf, uint8_t outp)
+{
+	unsigned nb_tx = rte_eth_tx_burst(outp, 0, outbuf->mbufs,
+			outbuf->count);
+	app_stats.tx.tx_pkts += nb_tx;
+
+	if (unlikely(nb_tx < outbuf->count)) {
+		LOG_DEBUG(DISTRAPP, "%s:Packet loss with tx_burst\n", __func__);
+		do {
+			rte_pktmbuf_free(outbuf->mbufs[nb_tx]);
+		} while (++nb_tx < outbuf->count);
+	}
+	outbuf->count = 0;
+}
+
+static inline void
+flush_all_ports(struct output_buffer *tx_buffers, uint8_t nb_ports)
+{
+	uint8_t outp;
+	for (outp = 0; outp < nb_ports; outp++) {
+		/* skip ports that are not enabled */
+		if ((enabled_port_mask & (1 << outp)) == 0)
+			continue;
+
+		if (tx_buffers[outp].count == 0)
+			continue;
+
+		flush_one_port(&tx_buffers[outp], outp);
+	}
+}
+
+static int
+lcore_tx(struct rte_ring *in_r)
+{
+	static struct output_buffer tx_buffers[RTE_MAX_ETHPORTS];
+	const uint8_t nb_ports = rte_eth_dev_count();
+	const int socket_id = rte_socket_id();
+	uint8_t port;
+
+	for (port = 0; port < nb_ports; port++) {
+		/* skip ports that are not enabled */
+		if ((enabled_port_mask & (1 << port)) == 0)
+			continue;
+
+		if (rte_eth_dev_socket_id(port) > 0 &&
+				rte_eth_dev_socket_id(port) != socket_id)
+			printf("WARNING, port %u is on remote NUMA node to "
+					"TX thread.\n\tPerformance will not "
+					"be optimal.\n", port);
+	}
+
+	printf("\nCore %u doing packet TX.\n", rte_lcore_id());
+	while (!quit_signal) {
+		for (port = 0; port < nb_ports; port++) {
+			/* skip ports that are not enabled */
+			if ((enabled_port_mask & (1 << port)) == 0)
+				continue;
+
+			struct rte_mbuf *bufs[BURST_SIZE];
+			const uint16_t nb_rx = rte_ring_dequeue_burst(in_r,
+					(void *)bufs, BURST_SIZE);
+			app_stats.tx.dequeue_pkts += nb_rx;
+
+			/* if we get no traffic, flush anything we have */
+			if (unlikely(nb_rx == 0)) {
+				flush_all_ports(tx_buffers, nb_ports);
+				continue;
+			}
+
+			/* for traffic we receive, queue it up for transmit */
+			uint16_t i;
+			_mm_prefetch(bufs[0], 0);
+			_mm_prefetch(bufs[1], 0);
+			_mm_prefetch(bufs[2], 0);
+			for (i = 0; i < nb_rx; i++) {
+				struct output_buffer *outbuf;
+				uint8_t outp;
+				_mm_prefetch(bufs[i + 3], 0);
+				/* workers should update in_port to hold the
+				 * output port value */
+				outp = bufs[i]->port;
+				/* skip ports that are not enabled */
+				if ((enabled_port_mask & (1 << outp)) == 0)
+					continue;
+
+				outbuf = &tx_buffers[outp];
+				outbuf->mbufs[outbuf->count++] = bufs[i];
+				if (outbuf->count == BURST_SIZE)
+					flush_one_port(outbuf, outp);
+			}
+		}
+	}
+}
+
+static __attribute__((noreturn)) void
+lcore_worker(struct lcore_params *p)
+{
+	struct rte_distributor *d = p->d;
+	const unsigned id = p->worker_id;
+	/* for single port, xor_val will be zero so we won't modify the output
+	 * port, otherwise we send traffic from 0 to 1, 2 to 3, and vice versa
+	 */
+	const unsigned xor_val = (rte_eth_dev_count() > 1);
+	struct rte_mbuf *buf = NULL;
+
+	printf("\nCore %u acting as worker core.\n", rte_lcore_id());
+	for (;;) {
+		buf = rte_distributor_get_pkt(d, id, buf);
+		buf->port ^= xor_val;
+	}
+}
+
+static void
+int_handler(int sig_num)
+{
+	struct rte_eth_stats eth_stats;
+	unsigned i;
+
+	printf("Exiting on signal %d\n", sig_num);
+
+	printf("\nRX thread stats:\n");
+	printf(" - Received:    %"PRIu64"\n", app_stats.rx.rx_pkts);
+	printf(" - Processed:   %"PRIu64"\n", app_stats.rx.returned_pkts);
+	printf(" - Enqueued:    %"PRIu64"\n", app_stats.rx.enqueued_pkts);
+
+	printf("\nTX thread stats:\n");
+	printf(" - Dequeued:    %"PRIu64"\n", app_stats.tx.dequeue_pkts);
+	printf(" - Transmitted: %"PRIu64"\n", app_stats.tx.tx_pkts);
+
+	for (i = 0; i < rte_eth_dev_count(); i++) {
+		rte_eth_stats_get(i, &eth_stats);
+		printf("\nPort %u stats:\n", i);
+		printf(" - Pkts in:   %"PRIu64"\n", eth_stats.ipackets);
+		printf(" - Pkts out:  %"PRIu64"\n", eth_stats.opackets);
+		printf(" - In Errs:   %"PRIu64"\n", eth_stats.ierrors);
+		printf(" - Out Errs:  %"PRIu64"\n", eth_stats.oerrors);
+		printf(" - Mbuf Errs: %"PRIu64"\n", eth_stats.rx_nombuf);
+	}
+	quit_signal = 1;
+}
+
+/* display usage */
+static void
+print_usage(const char *prgname)
+{
+	printf("%s [EAL options] -- -p PORTMASK\n"
+			"  -p PORTMASK: hexadecimal bitmask of ports to configure\n",
+			prgname);
+}
+
+static int
+parse_portmask(const char *portmask)
+{
+	char *end = NULL;
+	unsigned long pm;
+
+	/* parse hexadecimal string */
+	pm = strtoul(portmask, &end, 16);
+	if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0'))
+		return -1;
+
+	if (pm == 0)
+		return -1;
+
+	return pm;
+}
+
+/* Parse the argument given in the command line of the application */
+static int
+parse_args(int argc, char **argv)
+{
+	int opt;
+	char **argvopt;
+	int option_index;
+	char *prgname = argv[0];
+	static struct option lgopts[] = {
+		{NULL, 0, 0, 0}
+	};
+
+	argvopt = argv;
+
+	while ((opt = getopt_long(argc, argvopt, "p:",
+			lgopts, &option_index)) != EOF) {
+
+		switch (opt) {
+			/* portmask */
+			case 'p':
+				enabled_port_mask = parse_portmask(optarg);
+				if (enabled_port_mask == 0) {
+					printf("invalid portmask\n");
+					print_usage(prgname);
+					return -1;
+				}
+				break;
+
+			default:
+				print_usage(prgname);
+				return -1;
+		}
+	}
+
+if (optind <= 1) {
+	print_usage(prgname);
+	return -1;
+}
+
+	argv[optind-1] = prgname;
+
+	optind = 0; /* reset getopt lib */
+	return 0;
+}
+
+/* Main function, does initialization and calls the per-lcore functions */
+int
+MAIN(int argc, char *argv[])
+{
+	struct rte_mempool *mbuf_pool;
+	struct rte_distributor *d;
+	struct rte_ring *output_ring;
+	unsigned lcore_id, worker_id = 0;
+	unsigned nb_ports;
+	uint8_t portid;
+	uint8_t nb_ports_available;
+
+	/* catch ctrl-c so we can print on exit */
+	signal(SIGINT, int_handler);
+
+	/* init EAL */
+	int ret = rte_eal_init(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Error with EAL initialization\n");
+	argc -= ret;
+	argv += ret;
+
+	/* parse application arguments (after the EAL ones) */
+	ret = parse_args(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Invalid distributor parameters\n");
+
+	if (rte_lcore_count() < 3)
+		rte_exit(EXIT_FAILURE, "Error, This application needs at "
+				"least 3 logical cores to run:\n"
+				"1 lcore for packet RX and distribution\n"
+				"1 lcore for packet TX\n"
+				"and at least 1 lcore for worker threads\n");
+
+	if (rte_eal_pci_probe() != 0)
+		rte_exit(EXIT_FAILURE, "Error with PCI probing\n");
+
+	nb_ports = rte_eth_dev_count();
+	if (nb_ports == 0)
+		rte_exit(EXIT_FAILURE, "Error: no ethernet ports detected\n");
+	if (nb_ports != 1 && (nb_ports & 1))
+		rte_exit(EXIT_FAILURE, "Error: number of ports must be even, except "
+				"when using a single port\n");
+
+	mbuf_pool = rte_mempool_create("MBUF_POOL", NUM_MBUFS * nb_ports,
+			MBUF_SIZE, MBUF_CACHE_SIZE,
+			sizeof(struct rte_pktmbuf_pool_private),
+			rte_pktmbuf_pool_init, NULL,
+			rte_pktmbuf_init, NULL,
+			rte_socket_id(), 0);
+	if (mbuf_pool == NULL)
+		rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
+
+	nb_ports_available = nb_ports;
+
+	/* initialize all ports */
+	for (portid = 0; portid < nb_ports; portid++) {
+		/* skip ports that are not enabled */
+		if ((enabled_port_mask & (1 << portid)) == 0) {
+			printf("\nSkipping disabled port %d\n", portid);
+			nb_ports_available--;
+			continue;
+		}
+		/* init port */
+		printf("Initializing port %u... done\n", (unsigned) portid);
+
+		if (port_init(portid, mbuf_pool) != 0)
+			rte_exit(EXIT_FAILURE, "Cannot initialize port %"PRIu8"\n",
+					portid);
+	}
+
+	if (!nb_ports_available) {
+		rte_exit(EXIT_FAILURE,
+				"All available ports are disabled. Please set portmask.\n");
+	}
+
+	d = rte_distributor_create("PKT_DIST", rte_socket_id(),
+			rte_lcore_count() - 2);
+	if (d == NULL)
+		rte_exit(EXIT_FAILURE, "Cannot create distributor\n");
+
+	/* scheduler ring is read only by the transmitter core, but written to
+	 * by multiple threads
+	 */
+	output_ring = rte_ring_create("Output_ring", RTE_RING_SZ,
+			rte_socket_id(), RING_F_SC_DEQ);
+	if (output_ring == NULL)
+		rte_exit(EXIT_FAILURE, "Cannot create output ring\n");
+
+	RTE_LCORE_FOREACH_SLAVE(lcore_id) {
+		if (worker_id == rte_lcore_count() - 2)
+			rte_eal_remote_launch((lcore_function_t *)lcore_tx,
+					output_ring, lcore_id);
+		else {
+			struct lcore_params *p =
+					rte_malloc(NULL, sizeof(*p), 0);
+			if (!p)
+				rte_panic("malloc failure\n");
+			*p = (struct lcore_params){worker_id, d, output_ring};
+			rte_eal_remote_launch((lcore_function_t *)lcore_worker,
+					p, lcore_id);
+		}
+		worker_id++;
+	}
+	/* call lcore_main on master core only */
+	struct lcore_params p = { 0, d, output_ring };
+	lcore_rx(&p);
+	return 0;
+}
diff --git a/examples/distributor_app/main.h b/examples/distributor_app/main.h
new file mode 100644
index 0000000..2682d15
--- /dev/null
+++ b/examples/distributor_app/main.h
@@ -0,0 +1,46 @@
+/*-
+ *   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.
+ */
+
+#ifndef _MAIN_H_
+#define _MAIN_H_
+
+
+#ifdef RTE_EXEC_ENV_BAREMETAL
+#define MAIN _main
+#else
+#define MAIN main
+#endif
+
+int MAIN(int argc, char *argv[]);
+
+#endif /* ifndef _MAIN_H_ */
-- 
1.7.4.1