[dpdk-dev] [PATCH v3] examples/skeleton: very simple code for packet forwarding

[Thomas Monjalon <thomas.monjalon@6wind.com>]

From: Bruce Richardson <bruce.richardson@intel.com>

This is a very simple example app for doing packet forwarding with the
Intel DPDK. It's designed to serve as a start point for people new to
the Intel DPDK and who want to develop a new app.

Therefore it's meant to:
* have as good a performance out-of-the-box as possible, using the
  best-known settings for configuring the PMDs, so that any new apps can
  be based off it.
* be kept as short as possible to make it easy to understand it and get
  started with it.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---

v3 changes:
- rename skeleton_app/ to skeleton/
- add in examples Makefile
- fix default target to native
- reword header guard
- rename rxRings to rx_rings and txRings to tx_rings

 examples/Makefile                |   1 +
 examples/{ => skeleton}/Makefile |  52 ++++-------
 examples/skeleton/basicfwd.c     | 183 +++++++++++++++++++++++++++++++++++++++
 examples/skeleton/basicfwd.h     |  46 ++++++++++
 4 files changed, 249 insertions(+), 33 deletions(-)
 copy examples/{ => skeleton}/Makefile (60%)
 create mode 100644 examples/skeleton/basicfwd.c
 create mode 100644 examples/skeleton/basicfwd.h

diff --git a/examples/Makefile b/examples/Makefile
index 121dab4..8055297 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -61,6 +61,7 @@ DIRS-y += netmap_compat/bridge
 DIRS-$(CONFIG_RTE_LIBRTE_METER) += qos_meter
 DIRS-$(CONFIG_RTE_LIBRTE_SCHED) += qos_sched
 DIRS-y += quota_watermark
+DIRS-y += skeleton
 DIRS-y += timer
 DIRS-$(CONFIG_RTE_LIBRTE_VHOST) += vhost
 DIRS-$(CONFIG_RTE_LIBRTE_XEN_DOM0) += vhost_xen
diff --git a/examples/Makefile b/examples/skeleton/Makefile
similarity index 60%
copy from examples/Makefile
copy to examples/skeleton/Makefile
index 121dab4..4a5d99f 100644
--- a/examples/Makefile
+++ b/examples/skeleton/Makefile
@@ -1,6 +1,7 @@
 #   BSD LICENSE
 #
-#   Copyright(c) 2014 6WIND S.A.
+#   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
@@ -12,7 +13,7 @@
 #       notice, this list of conditions and the following disclaimer in
 #       the documentation and/or other materials provided with the
 #       distribution.
-#     * Neither the name of 6WIND S.A. nor the names of its
+#     * 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.
 #
@@ -32,40 +33,25 @@ ifeq ($(RTE_SDK),)
 $(error "Please define RTE_SDK environment variable")
 endif
 
-# Default target, can be overriden by command line or environment
+# Default target, can be overridden by command line or environment
 RTE_TARGET ?= x86_64-native-linuxapp-gcc
 
 include $(RTE_SDK)/mk/rte.vars.mk
 
-DIRS-y += cmdline
-ifneq ($(ICP_ROOT),)
-DIRS-y += dpdk_qat
+# binary name
+APP = basicfwd
+
+# all source are stored in SRCS-y
+SRCS-y := basicfwd.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
-DIRS-y += exception_path
-DIRS-y += helloworld
-DIRS-y += ip_pipeline
-DIRS-y += ip_reassembly
-DIRS-$(CONFIG_RTE_MBUF_REFCNT) += ip_fragmentation
-DIRS-$(CONFIG_RTE_MBUF_REFCNT) += ipv4_multicast
-DIRS-$(CONFIG_RTE_LIBRTE_KNI) += kni
-DIRS-y += l2fwd
-DIRS-$(CONFIG_RTE_LIBRTE_IVSHMEM) += l2fwd-ivshmem
-DIRS-y += l3fwd
-DIRS-$(CONFIG_RTE_LIBRTE_ACL) += l3fwd-acl
-DIRS-$(CONFIG_RTE_LIBRTE_POWER) += l3fwd-power
-DIRS-y += l3fwd-vf
-DIRS-y += link_status_interrupt
-DIRS-y += load_balancer
-DIRS-y += multi_process
-DIRS-y += netmap_compat/bridge
-DIRS-$(CONFIG_RTE_LIBRTE_METER) += qos_meter
-DIRS-$(CONFIG_RTE_LIBRTE_SCHED) += qos_sched
-DIRS-y += quota_watermark
-DIRS-y += timer
-DIRS-$(CONFIG_RTE_LIBRTE_VHOST) += vhost
-DIRS-$(CONFIG_RTE_LIBRTE_XEN_DOM0) += vhost_xen
-DIRS-y += vmdq
-DIRS-y += vmdq_dcb
-DIRS-$(CONFIG_RTE_LIBRTE_DISTRIBUTOR) += distributor
 
-include $(RTE_SDK)/mk/rte.extsubdir.mk
+EXTRA_CFLAGS += -O3 -g -Wfatal-errors
+
+include $(RTE_SDK)/mk/rte.extapp.mk
diff --git a/examples/skeleton/basicfwd.c b/examples/skeleton/basicfwd.c
new file mode 100644
index 0000000..ef8f90c
--- /dev/null
+++ b/examples/skeleton/basicfwd.c
@@ -0,0 +1,183 @@
+/*-
+ *   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 <rte_eal.h>
+#include <rte_ethdev.h>
+#include <rte_cycles.h>
+#include <rte_lcore.h>
+#include <rte_mbuf.h>
+#include "basicfwd.h"
+
+#define RX_RING_SIZE 128
+#define TX_RING_SIZE 512
+
+#define NUM_MBUFS 8191
+#define MBUF_SIZE (1600 + sizeof(struct rte_mbuf) + RTE_PKTMBUF_HEADROOM)
+#define MBUF_CACHE_SIZE 250
+#define BURST_SIZE 32
+
+static const struct rte_eth_conf port_conf_default = {
+	.rxmode = { .max_rx_pkt_len = ETHER_MAX_LEN, },
+};
+
+/*
+ * 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 rx_rings = 1, tx_rings = 1;
+	int retval;
+	uint16_t q;
+
+	if (port >= rte_eth_dev_count())
+		return -1;
+
+	retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
+	if (retval != 0)
+		return retval;
+
+	for (q = 0; q < rx_rings; q++) {
+		retval = rte_eth_rx_queue_setup(port, q, RX_RING_SIZE,
+				rte_eth_dev_socket_id(port), NULL, mbuf_pool);
+		if (retval < 0)
+			return retval;
+	}
+
+	for (q = 0; q < tx_rings; q++) {
+		retval = rte_eth_tx_queue_setup(port, q, TX_RING_SIZE,
+				rte_eth_dev_socket_id(port), NULL);
+		if (retval < 0)
+			return retval;
+	}
+
+	retval  = rte_eth_dev_start(port);
+	if (retval < 0)
+		return retval;
+
+	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;
+}
+
+/*
+ * Main thread that does the work, reading from INPUT_PORT
+ * and writing to OUTPUT_PORT
+ */
+static  __attribute__((noreturn)) void
+lcore_main(void)
+{
+	const uint8_t nb_ports = rte_eth_dev_count();
+	uint8_t port;
+	for (port = 0; port < nb_ports; port++)
+		if (rte_eth_dev_socket_id(port) > 0 &&
+				rte_eth_dev_socket_id(port) !=
+						(int)rte_socket_id())
+			printf("WARNING, port %u is on remote NUMA node to "
+					"polling thread.\n\tPerformance will "
+					"not be optimal.\n", port);
+
+	printf("\nCore %u forwarding packets. [Ctrl+C to quit]\n",
+			rte_lcore_id());
+	for (;;) {
+		for (port = 0; port < nb_ports; port++) {
+			struct rte_mbuf *bufs[BURST_SIZE];
+			const uint16_t nb_rx = rte_eth_rx_burst(port, 0,
+					bufs, BURST_SIZE);
+			if (unlikely(nb_rx == 0))
+				continue;
+			const uint16_t nb_tx = rte_eth_tx_burst(port ^ 1, 0,
+					bufs, nb_rx);
+			if (unlikely(nb_tx < nb_rx)) {
+				uint16_t buf;
+				for (buf = nb_tx; buf < nb_rx; buf++)
+					rte_pktmbuf_free(bufs[buf]);
+			}
+		}
+	}
+}
+
+/* Main function, does initialisation and calls the per-lcore functions */
+int
+MAIN(int argc, char *argv[])
+{
+	struct rte_mempool *mbuf_pool;
+	unsigned nb_ports;
+	uint8_t portid;
+
+	/* 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;
+
+	nb_ports = rte_eth_dev_count();
+	if (nb_ports < 2 || (nb_ports & 1))
+		rte_exit(EXIT_FAILURE, "Error: number of ports must be even\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");
+
+	/* initialize all ports */
+	for (portid = 0; portid < nb_ports; portid++)
+		if (port_init(portid, mbuf_pool) != 0)
+			rte_exit(EXIT_FAILURE, "Cannot init port %"PRIu8"\n",
+					portid);
+
+	if (rte_lcore_count() > 1)
+		printf("\nWARNING: Too much enabled lcores - App uses only 1 lcore\n");
+
+	/* call lcore_main on master core only */
+	lcore_main();
+	return 0;
+}
diff --git a/examples/skeleton/basicfwd.h b/examples/skeleton/basicfwd.h
new file mode 100644
index 0000000..3797b5d
--- /dev/null
+++ b/examples/skeleton/basicfwd.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 BASICFWD_H
+#define BASICFWD_H
+
+
+#ifdef RTE_EXEC_ENV_BAREMETAL
+#define MAIN _main
+#else
+#define MAIN main
+#endif
+
+int MAIN(int argc, char *argv[]);
+
+#endif /* BASICFWD_H */
-- 
2.1.3