Adding upstream version 14.2.21.upstream/14.2.21upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

14 files changed, 1416 insertions, 0 deletions

diff --git a/src/seastar/dpdk/examples/quota_watermark/Makefile b/src/seastar/dpdk/examples/quota_watermark/Makefile
new file mode 100644
index 00000000..17fe473b
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/Makefile
@@ -0,0 +1,44 @@
+#   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 $(RTE_SDK)/mk/rte.vars.mk
+
+DIRS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += qw
+DIRS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += qwctl
+
+include $(RTE_SDK)/mk/rte.extsubdir.mk
diff --git a/src/seastar/dpdk/examples/quota_watermark/include/conf.h b/src/seastar/dpdk/examples/quota_watermark/include/conf.h
new file mode 100644
index 00000000..bdc3bbed
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/include/conf.h
@@ -0,0 +1,48 @@
+/*-
+ *   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 _CONF_H_
+#define _CONF_H_
+
+#define RING_SIZE 1024
+#define MAX_PKT_QUOTA 64
+
+#define RX_DESC_PER_QUEUE   128
+#define TX_DESC_PER_QUEUE   512
+
+#define MBUF_DATA_SIZE     RTE_MBUF_DEFAULT_BUF_SIZE
+#define MBUF_PER_POOL 8192
+
+#define QUOTA_WATERMARK_MEMZONE_NAME "qw_global_vars"
+
+#endif /* _CONF_H_ */
diff --git a/src/seastar/dpdk/examples/quota_watermark/qw/Makefile b/src/seastar/dpdk/examples/quota_watermark/qw/Makefile
new file mode 100644
index 00000000..fac9328d
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qw/Makefile
@@ -0,0 +1,50 @@
+#   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 = qw
+
+# all source are stored in SRCS-y
+SRCS-y := args.c init.c main.c
+
+CFLAGS += -O3 -DQW_SOFTWARE_FC
+CFLAGS += $(WERROR_FLAGS)
+
+include $(RTE_SDK)/mk/rte.extapp.mk
diff --git a/src/seastar/dpdk/examples/quota_watermark/qw/args.c b/src/seastar/dpdk/examples/quota_watermark/qw/args.c
new file mode 100644
index 00000000..6ba77bc0
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qw/args.c
@@ -0,0 +1,107 @@
+/*-
+ *   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 <unistd.h>
+
+#include <rte_common.h>
+#include <rte_lcore.h>
+
+#include "args.h"
+
+
+unsigned int portmask = 0;
+
+
+static void
+usage(const char *prgname)
+{
+	fprintf(stderr, "Usage: %s [EAL args] -- -p <portmask>\n"
+			"-p PORTMASK: hexadecimal bitmask of NIC ports to configure\n",
+			prgname);
+}
+
+static unsigned long
+parse_portmask(const char *portmask_str)
+{
+	return strtoul(portmask_str, NULL, 16);
+}
+
+static void
+check_core_count(void)
+{
+	if (rte_lcore_count() < 3)
+		rte_exit(EXIT_FAILURE,
+				"At least 3 cores need to be passed in the coremask\n");
+}
+
+static void
+check_portmask_value(unsigned int portmask)
+{
+	unsigned int port_nb = 0;
+
+	port_nb = __builtin_popcount(portmask);
+
+	if (port_nb == 0)
+		rte_exit(EXIT_FAILURE,
+				"At least 2 ports need to be passed in the portmask\n");
+
+	if (port_nb % 2 != 0)
+		rte_exit(EXIT_FAILURE,
+				"An even number of ports is required in the portmask\n");
+}
+
+int
+parse_qw_args(int argc, char **argv)
+{
+	int opt;
+
+	while ((opt = getopt(argc, argv, "h:p:")) != -1) {
+		switch (opt) {
+		case 'h':
+			usage(argv[0]);
+			break;
+		case 'p':
+			portmask = parse_portmask(optarg);
+			break;
+		default:
+			usage(argv[0]);
+		}
+	}
+
+	check_core_count();
+	check_portmask_value(portmask);
+
+	return 0;
+}
diff --git a/src/seastar/dpdk/examples/quota_watermark/qw/args.h b/src/seastar/dpdk/examples/quota_watermark/qw/args.h
new file mode 100644
index 00000000..d6d4fb62
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qw/args.h
@@ -0,0 +1,41 @@
+/*-
+ *   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 _ARGS_H_
+#define _ARGS_H_
+
+extern unsigned int portmask;
+
+int parse_qw_args(int argc, char **argv);
+
+#endif /* _ARGS_H_ */
diff --git a/src/seastar/dpdk/examples/quota_watermark/qw/init.c b/src/seastar/dpdk/examples/quota_watermark/qw/init.c
new file mode 100644
index 00000000..b6264fcf
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qw/init.c
@@ -0,0 +1,178 @@
+/*-
+ *   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 <fcntl.h>
+#include <unistd.h>
+#include <sys/mman.h>
+
+#include <rte_eal.h>
+
+#include <rte_common.h>
+#include <rte_errno.h>
+#include <rte_ethdev.h>
+#include <rte_memzone.h>
+#include <rte_ring.h>
+#include <rte_string_fns.h>
+
+#include "args.h"
+#include "init.h"
+#include "main.h"
+#include "../include/conf.h"
+
+
+static const struct rte_eth_conf port_conf = {
+		.rxmode = {
+			.split_hdr_size = 0,
+			.header_split   = 0, /**< Header Split disabled */
+			.hw_ip_checksum = 0, /**< IP csum offload disabled */
+			.hw_vlan_filter = 0, /**< VLAN filtering disabled */
+			.jumbo_frame    = 0, /**< Jumbo Frame disabled */
+			.hw_strip_crc   = 1, /**< CRC stripped by hardware */
+		},
+		.txmode = {
+			.mq_mode = ETH_DCB_NONE,
+		},
+};
+
+static struct rte_eth_fc_conf fc_conf = {
+		.mode       = RTE_FC_TX_PAUSE,
+		.high_water = 80 * 510 / 100,
+		.low_water  = 60 * 510 / 100,
+		.pause_time = 1337,
+		.send_xon   = 0,
+};
+
+
+void configure_eth_port(uint8_t port_id)
+{
+	int ret;
+
+	rte_eth_dev_stop(port_id);
+
+	ret = rte_eth_dev_configure(port_id, 1, 1, &port_conf);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Cannot configure port %u (error %d)\n",
+				(unsigned int) port_id, ret);
+
+	/* Initialize the port's RX queue */
+	ret = rte_eth_rx_queue_setup(port_id, 0, RX_DESC_PER_QUEUE,
+			rte_eth_dev_socket_id(port_id),
+			NULL,
+			mbuf_pool);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE,
+				"Failed to setup RX queue on port %u (error %d)\n",
+				(unsigned int) port_id, ret);
+
+	/* Initialize the port's TX queue */
+	ret = rte_eth_tx_queue_setup(port_id, 0, TX_DESC_PER_QUEUE,
+			rte_eth_dev_socket_id(port_id),
+			NULL);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE,
+				"Failed to setup TX queue on port %u (error %d)\n",
+				(unsigned int) port_id, ret);
+
+	/* Initialize the port's flow control */
+	ret = rte_eth_dev_flow_ctrl_set(port_id, &fc_conf);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE,
+				"Failed to setup hardware flow control on port %u (error %d)\n",
+				(unsigned int) port_id, ret);
+
+	/* Start the port */
+	ret = rte_eth_dev_start(port_id);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Failed to start port %u (error %d)\n",
+				(unsigned int) port_id, ret);
+
+	/* Put it in promiscuous mode */
+	rte_eth_promiscuous_enable(port_id);
+}
+
+void
+init_dpdk(void)
+{
+	if (rte_eth_dev_count() < 2)
+		rte_exit(EXIT_FAILURE, "Not enough ethernet port available\n");
+}
+
+void init_ring(int lcore_id, uint8_t port_id)
+{
+	struct rte_ring *ring;
+	char ring_name[RTE_RING_NAMESIZE];
+
+	snprintf(ring_name, RTE_RING_NAMESIZE,
+			"core%d_port%d", lcore_id, port_id);
+	ring = rte_ring_create(ring_name, RING_SIZE, rte_socket_id(),
+			RING_F_SP_ENQ | RING_F_SC_DEQ);
+
+	if (ring == NULL)
+		rte_exit(EXIT_FAILURE, "%s\n", rte_strerror(rte_errno));
+
+	*high_watermark = 80 * RING_SIZE / 100;
+
+	rings[lcore_id][port_id] = ring;
+}
+
+void
+pair_ports(void)
+{
+	uint8_t i, j;
+
+	/* Pair ports with their "closest neighbour" in the portmask */
+	for (i = 0; i < RTE_MAX_ETHPORTS; i++)
+		if (is_bit_set(i, portmask))
+			for (j = (uint8_t) (i + 1); j < RTE_MAX_ETHPORTS; j++)
+				if (is_bit_set(j, portmask)) {
+					port_pairs[i] = j;
+					port_pairs[j] = i;
+					i = j;
+					break;
+				}
+}
+
+void
+setup_shared_variables(void)
+{
+	const struct rte_memzone *qw_memzone;
+
+	qw_memzone = rte_memzone_reserve(QUOTA_WATERMARK_MEMZONE_NAME,
+			3 * sizeof(int), rte_socket_id(), 0);
+	if (qw_memzone == NULL)
+		rte_exit(EXIT_FAILURE, "%s\n", rte_strerror(rte_errno));
+
+	quota = qw_memzone->addr;
+	low_watermark = (unsigned int *) qw_memzone->addr + 1;
+	high_watermark = (unsigned int *) qw_memzone->addr + 2;
+}
diff --git a/src/seastar/dpdk/examples/quota_watermark/qw/init.h b/src/seastar/dpdk/examples/quota_watermark/qw/init.h
new file mode 100644
index 00000000..6d0af3ab
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qw/init.h
@@ -0,0 +1,43 @@
+/*-
+ *   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 _INIT_H_
+#define _INIT_H_
+
+void configure_eth_port(uint8_t port_id);
+void init_dpdk(void);
+void init_ring(int lcore_id, uint8_t port_id);
+void pair_ports(void);
+void setup_shared_variables(void);
+
+#endif /* _INIT_H_ */
diff --git a/src/seastar/dpdk/examples/quota_watermark/qw/main.c b/src/seastar/dpdk/examples/quota_watermark/qw/main.c
new file mode 100644
index 00000000..d4fcfde4
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qw/main.c
@@ -0,0 +1,392 @@
+/*-
+ *   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 <rte_eal.h>
+
+#include <rte_common.h>
+#include <rte_debug.h>
+#include <rte_errno.h>
+#include <rte_ethdev.h>
+#include <rte_launch.h>
+#include <rte_lcore.h>
+#include <rte_log.h>
+#include <rte_mbuf.h>
+#include <rte_ring.h>
+
+#include <rte_byteorder.h>
+
+#include "args.h"
+#include "main.h"
+#include "init.h"
+#include "../include/conf.h"
+
+
+#ifdef QW_SOFTWARE_FC
+#define SEND_PAUSE_FRAME(port_id, duration) send_pause_frame(port_id, duration)
+#else
+#define SEND_PAUSE_FRAME(port_id, duration) do { } while(0)
+#endif
+
+#define ETHER_TYPE_FLOW_CONTROL 0x8808
+
+struct ether_fc_frame {
+	uint16_t opcode;
+	uint16_t param;
+} __attribute__((__packed__));
+
+
+int *quota;
+unsigned int *low_watermark;
+unsigned int *high_watermark;
+
+uint8_t port_pairs[RTE_MAX_ETHPORTS];
+
+struct rte_ring *rings[RTE_MAX_LCORE][RTE_MAX_ETHPORTS];
+struct rte_mempool *mbuf_pool;
+
+
+static void send_pause_frame(uint8_t port_id, uint16_t duration)
+{
+	struct rte_mbuf *mbuf;
+	struct ether_fc_frame *pause_frame;
+	struct ether_hdr *hdr;
+	struct ether_addr mac_addr;
+
+	RTE_LOG_DP(DEBUG, USER1,
+			"Sending PAUSE frame (duration=%d) on port %d\n",
+			duration, port_id);
+
+	/* Get a mbuf from the pool */
+	mbuf = rte_pktmbuf_alloc(mbuf_pool);
+	if (unlikely(mbuf == NULL))
+		return;
+
+	/* Prepare a PAUSE frame */
+	hdr = rte_pktmbuf_mtod(mbuf, struct ether_hdr *);
+	pause_frame = (struct ether_fc_frame *) &hdr[1];
+
+	rte_eth_macaddr_get(port_id, &mac_addr);
+	ether_addr_copy(&mac_addr, &hdr->s_addr);
+
+	void *tmp = &hdr->d_addr.addr_bytes[0];
+	*((uint64_t *)tmp) = 0x010000C28001ULL;
+
+	hdr->ether_type = rte_cpu_to_be_16(ETHER_TYPE_FLOW_CONTROL);
+
+	pause_frame->opcode = rte_cpu_to_be_16(0x0001);
+	pause_frame->param  = rte_cpu_to_be_16(duration);
+
+	mbuf->pkt_len  = 60;
+	mbuf->data_len = 60;
+
+	rte_eth_tx_burst(port_id, 0, &mbuf, 1);
+}
+
+/**
+ * Get the previous enabled lcore ID
+ *
+ * @param lcore_id
+ *   The current lcore ID.
+ * @return
+ *   The previous enabled lcore_id or -1 if not found.
+ */
+static unsigned int
+get_previous_lcore_id(unsigned int lcore_id)
+{
+	int i;
+
+	for (i = lcore_id - 1; i >= 0; i--)
+		if (rte_lcore_is_enabled(i))
+			return i;
+
+	return -1;
+}
+
+/**
+ * Get the last enabled lcore ID
+ *
+ * @return
+ *   The last enabled lcore_id.
+ */
+static unsigned int
+get_last_lcore_id(void)
+{
+	int i;
+
+	for (i = RTE_MAX_LCORE; i >= 0; i--)
+		if (rte_lcore_is_enabled(i))
+			return i;
+
+	return 0;
+}
+
+static void
+receive_stage(__attribute__((unused)) void *args)
+{
+	int i, ret;
+
+	uint8_t port_id;
+	uint16_t nb_rx_pkts;
+
+	unsigned int lcore_id;
+	unsigned int free;
+
+	struct rte_mbuf *pkts[MAX_PKT_QUOTA];
+	struct rte_ring *ring;
+	enum ring_state ring_state[RTE_MAX_ETHPORTS] = { RING_READY };
+
+	lcore_id = rte_lcore_id();
+
+	RTE_LOG(INFO, USER1,
+			"%s() started on core %u\n", __func__, lcore_id);
+
+	while (1) {
+
+		/* Process each port round robin style */
+		for (port_id = 0; port_id < RTE_MAX_ETHPORTS; port_id++) {
+
+			if (!is_bit_set(port_id, portmask))
+				continue;
+
+			ring = rings[lcore_id][port_id];
+
+			if (ring_state[port_id] != RING_READY) {
+				if (rte_ring_count(ring) > *low_watermark)
+					continue;
+				else
+					ring_state[port_id] = RING_READY;
+			}
+
+			/* Enqueue received packets on the RX ring */
+			nb_rx_pkts = rte_eth_rx_burst(port_id, 0, pkts,
+					(uint16_t) *quota);
+			ret = rte_ring_enqueue_bulk(ring, (void *) pkts,
+					nb_rx_pkts, &free);
+			if (RING_SIZE - free > *high_watermark) {
+				ring_state[port_id] = RING_OVERLOADED;
+				send_pause_frame(port_id, 1337);
+			}
+
+			if (ret == 0) {
+
+				/*
+				 * Return  mbufs to the pool,
+				 * effectively dropping packets
+				 */
+				for (i = 0; i < nb_rx_pkts; i++)
+					rte_pktmbuf_free(pkts[i]);
+			}
+		}
+	}
+}
+
+static void
+pipeline_stage(__attribute__((unused)) void *args)
+{
+	int i, ret;
+	int nb_dq_pkts;
+
+	uint8_t port_id;
+
+	unsigned int lcore_id, previous_lcore_id;
+	unsigned int free;
+
+	void *pkts[MAX_PKT_QUOTA];
+	struct rte_ring *rx, *tx;
+	enum ring_state ring_state[RTE_MAX_ETHPORTS] = { RING_READY };
+
+	lcore_id = rte_lcore_id();
+	previous_lcore_id = get_previous_lcore_id(lcore_id);
+
+	RTE_LOG(INFO, USER1,
+			"%s() started on core %u - processing packets from core %u\n",
+			__func__, lcore_id, previous_lcore_id);
+
+	while (1) {
+
+		for (port_id = 0; port_id < RTE_MAX_ETHPORTS; port_id++) {
+
+			if (!is_bit_set(port_id, portmask))
+				continue;
+
+			tx = rings[lcore_id][port_id];
+			rx = rings[previous_lcore_id][port_id];
+
+			if (ring_state[port_id] != RING_READY) {
+				if (rte_ring_count(tx) > *low_watermark)
+					continue;
+				else
+					ring_state[port_id] = RING_READY;
+			}
+
+			/* Dequeue up to quota mbuf from rx */
+			nb_dq_pkts = rte_ring_dequeue_burst(rx, pkts,
+					*quota, NULL);
+			if (unlikely(nb_dq_pkts < 0))
+				continue;
+
+			/* Enqueue them on tx */
+			ret = rte_ring_enqueue_bulk(tx, pkts,
+					nb_dq_pkts, &free);
+			if (RING_SIZE - free > *high_watermark)
+				ring_state[port_id] = RING_OVERLOADED;
+
+			if (ret == 0) {
+
+				/*
+				 * Return  mbufs to the pool,
+				 * effectively dropping packets
+				 */
+				for (i = 0; i < nb_dq_pkts; i++)
+					rte_pktmbuf_free(pkts[i]);
+			}
+		}
+	}
+}
+
+static void
+send_stage(__attribute__((unused)) void *args)
+{
+	uint16_t nb_dq_pkts;
+
+	uint8_t port_id;
+	uint8_t dest_port_id;
+
+	unsigned int lcore_id, previous_lcore_id;
+
+	struct rte_ring *tx;
+	struct rte_mbuf *tx_pkts[MAX_PKT_QUOTA];
+
+	lcore_id = rte_lcore_id();
+	previous_lcore_id = get_previous_lcore_id(lcore_id);
+
+	RTE_LOG(INFO, USER1,
+			"%s() started on core %u - processing packets from core %u\n",
+			__func__, lcore_id, previous_lcore_id);
+
+	while (1) {
+
+		/* Process each ring round robin style */
+		for (port_id = 0; port_id < RTE_MAX_ETHPORTS; port_id++) {
+
+			if (!is_bit_set(port_id, portmask))
+				continue;
+
+			dest_port_id = port_pairs[port_id];
+			tx = rings[previous_lcore_id][port_id];
+
+			if (rte_ring_empty(tx))
+				continue;
+
+			/* Dequeue packets from tx and send them */
+			nb_dq_pkts = (uint16_t) rte_ring_dequeue_burst(tx,
+					(void *) tx_pkts, *quota, NULL);
+			rte_eth_tx_burst(dest_port_id, 0, tx_pkts, nb_dq_pkts);
+
+			/* TODO: Check if nb_dq_pkts == nb_tx_pkts? */
+		}
+	}
+}
+
+int
+main(int argc, char **argv)
+{
+	int ret;
+	unsigned int lcore_id, master_lcore_id, last_lcore_id;
+
+	uint8_t port_id;
+
+	rte_log_set_global_level(RTE_LOG_INFO);
+
+	ret = rte_eal_init(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Cannot initialize EAL\n");
+
+	argc -= ret;
+	argv += ret;
+
+	init_dpdk();
+	setup_shared_variables();
+
+	*quota = 32;
+	*low_watermark = 60 * RING_SIZE / 100;
+
+	last_lcore_id   = get_last_lcore_id();
+	master_lcore_id = rte_get_master_lcore();
+
+	/* Parse the application's arguments */
+	ret = parse_qw_args(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Invalid quota/watermark argument(s)\n");
+
+	/* Create a pool of mbuf to store packets */
+	mbuf_pool = rte_pktmbuf_pool_create("mbuf_pool", MBUF_PER_POOL, 32, 0,
+			MBUF_DATA_SIZE, rte_socket_id());
+	if (mbuf_pool == NULL)
+		rte_panic("%s\n", rte_strerror(rte_errno));
+
+	for (port_id = 0; port_id < RTE_MAX_ETHPORTS; port_id++)
+		if (is_bit_set(port_id, portmask)) {
+			configure_eth_port(port_id);
+			init_ring(master_lcore_id, port_id);
+		}
+
+	pair_ports();
+
+	/*
+	 * Start pipeline_connect() on all the available slave lcores
+	 * but the last
+	 */
+	for (lcore_id = 0 ; lcore_id < last_lcore_id; lcore_id++) {
+		if (rte_lcore_is_enabled(lcore_id) &&
+				lcore_id != master_lcore_id) {
+
+			for (port_id = 0; port_id < RTE_MAX_ETHPORTS; port_id++)
+				if (is_bit_set(port_id, portmask))
+					init_ring(lcore_id, port_id);
+
+			/* typecast is a workaround for GCC 4.3 bug */
+			rte_eal_remote_launch((int (*)(void *))pipeline_stage,
+					NULL, lcore_id);
+		}
+	}
+
+	/* Start send_stage() on the last slave core */
+	/* typecast is a workaround for GCC 4.3 bug */
+	rte_eal_remote_launch((int (*)(void *))send_stage, NULL, last_lcore_id);
+
+	/* Start receive_stage() on the master core */
+	receive_stage(NULL);
+
+	return 0;
+}
diff --git a/src/seastar/dpdk/examples/quota_watermark/qw/main.h b/src/seastar/dpdk/examples/quota_watermark/qw/main.h
new file mode 100644
index 00000000..8c8e3116
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qw/main.h
@@ -0,0 +1,60 @@
+/*-
+ *   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_
+
+#include "../include/conf.h"
+
+enum ring_state {
+	RING_READY,
+	RING_OVERLOADED,
+};
+
+extern int *quota;
+extern unsigned int *low_watermark;
+extern unsigned int *high_watermark;
+
+extern uint8_t port_pairs[RTE_MAX_ETHPORTS];
+
+extern struct rte_ring *rings[RTE_MAX_LCORE][RTE_MAX_ETHPORTS];
+extern struct rte_mempool *mbuf_pool;
+
+
+static inline int
+is_bit_set(int i, unsigned int mask)
+{
+	return (1 << i) & mask;
+}
+
+#endif /* _MAIN_H_ */
diff --git a/src/seastar/dpdk/examples/quota_watermark/qwctl/Makefile b/src/seastar/dpdk/examples/quota_watermark/qwctl/Makefile
new file mode 100644
index 00000000..1ca2f1e9
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qwctl/Makefile
@@ -0,0 +1,50 @@
+#   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 = qwctl
+
+# all source are stored in SRCS-y
+SRCS-y := commands.c qwctl.c
+
+CFLAGS += -O3
+CFLAGS += $(WERROR_FLAGS)
+
+include $(RTE_SDK)/mk/rte.extapp.mk
diff --git a/src/seastar/dpdk/examples/quota_watermark/qwctl/commands.c b/src/seastar/dpdk/examples/quota_watermark/qwctl/commands.c
new file mode 100644
index 00000000..5cac0e17
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qwctl/commands.c
@@ -0,0 +1,225 @@
+/*-
+ *   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 <stdint.h>
+#include <string.h>
+#include <termios.h>
+
+#include <cmdline_rdline.h>
+#include <cmdline_parse.h>
+#include <cmdline_parse_num.h>
+#include <cmdline_parse_string.h>
+#include <cmdline.h>
+
+#include <rte_ring.h>
+
+#include "qwctl.h"
+#include "../include/conf.h"
+
+
+/**
+ * help command
+ */
+
+struct cmd_help_tokens {
+	cmdline_fixed_string_t verb;
+};
+
+cmdline_parse_token_string_t cmd_help_verb =
+		TOKEN_STRING_INITIALIZER(struct cmd_help_tokens, verb, "help");
+
+static void
+cmd_help_handler(__attribute__((unused)) void *parsed_result,
+		struct cmdline *cl,
+		__attribute__((unused)) void *data)
+{
+	cmdline_printf(cl, "Available commands:\n"
+			"- help\n"
+			"- set  [ring_name|variable] <value>\n"
+			"- show [ring_name|variable]\n"
+			"\n"
+			"Available variables:\n"
+			"- low_watermark\n"
+			"- quota\n"
+			"- ring names follow the core%%u_port%%u format\n");
+}
+
+cmdline_parse_inst_t cmd_help = {
+		.f = cmd_help_handler,
+		.data = NULL,
+		.help_str = "show help",
+		.tokens = {
+				(void *) &cmd_help_verb,
+				NULL,
+		},
+};
+
+
+/**
+ * set command
+ */
+
+struct cmd_set_tokens {
+	cmdline_fixed_string_t verb;
+	cmdline_fixed_string_t variable;
+	uint32_t value;
+};
+
+cmdline_parse_token_string_t cmd_set_verb =
+		TOKEN_STRING_INITIALIZER(struct cmd_set_tokens, verb, "set");
+
+cmdline_parse_token_string_t cmd_set_variable =
+		TOKEN_STRING_INITIALIZER(struct cmd_set_tokens, variable, NULL);
+
+cmdline_parse_token_num_t cmd_set_value =
+		TOKEN_NUM_INITIALIZER(struct cmd_set_tokens, value, UINT32);
+
+static void
+cmd_set_handler(__attribute__((unused)) void *parsed_result,
+		struct cmdline *cl,
+		__attribute__((unused)) void *data)
+{
+	struct cmd_set_tokens *tokens = parsed_result;
+	struct rte_ring *ring;
+
+	if (!strcmp(tokens->variable, "quota")) {
+
+		if (tokens->value > 0 && tokens->value <= MAX_PKT_QUOTA)
+			*quota = tokens->value;
+		else
+			cmdline_printf(cl, "quota must be between 1 and %u\n",
+					MAX_PKT_QUOTA);
+	}
+
+	else if (!strcmp(tokens->variable, "low_watermark")) {
+
+		if (tokens->value <= 100)
+			*low_watermark = tokens->value * RING_SIZE / 100;
+		else
+			cmdline_printf(cl,
+					"low_watermark must be between 0%% and 100%%\n");
+	}
+
+	else {
+
+		ring = rte_ring_lookup(tokens->variable);
+		if (ring == NULL)
+			cmdline_printf(cl, "Cannot find ring \"%s\"\n",
+					tokens->variable);
+		else
+			if (tokens->value >= *low_watermark * 100 / RING_SIZE
+					&& tokens->value <= 100)
+				*high_watermark = tokens->value *
+						RING_SIZE / 100;
+			else
+				cmdline_printf(cl,
+					"ring high watermark must be between %u%% and 100%%\n",
+					*low_watermark * 100 / RING_SIZE);
+	}
+}
+
+cmdline_parse_inst_t cmd_set = {
+		.f = cmd_set_handler,
+		.data = NULL,
+		.help_str = "Set a variable value",
+		.tokens = {
+				(void *) &cmd_set_verb,
+				(void *) &cmd_set_variable,
+				(void *) &cmd_set_value,
+				NULL,
+		},
+};
+
+
+/**
+ * show command
+ */
+
+struct cmd_show_tokens {
+	cmdline_fixed_string_t verb;
+	cmdline_fixed_string_t variable;
+};
+
+cmdline_parse_token_string_t cmd_show_verb =
+		TOKEN_STRING_INITIALIZER(struct cmd_show_tokens, verb, "show");
+
+cmdline_parse_token_string_t cmd_show_variable =
+		TOKEN_STRING_INITIALIZER(struct cmd_show_tokens,
+				variable, NULL);
+
+
+static void
+cmd_show_handler(__attribute__((unused)) void *parsed_result,
+		struct cmdline *cl,
+		__attribute__((unused)) void *data)
+{
+	struct cmd_show_tokens *tokens = parsed_result;
+	struct rte_ring *ring;
+
+	if (!strcmp(tokens->variable, "quota"))
+		cmdline_printf(cl, "Global quota: %d\n", *quota);
+
+	else if (!strcmp(tokens->variable, "low_watermark"))
+		cmdline_printf(cl, "Global low_watermark: %u\n",
+				*low_watermark);
+
+	else {
+
+		ring = rte_ring_lookup(tokens->variable);
+		if (ring == NULL)
+			cmdline_printf(cl, "Cannot find ring \"%s\"\n",
+					tokens->variable);
+		else
+			rte_ring_dump(stdout, ring);
+	}
+}
+
+cmdline_parse_inst_t cmd_show = {
+		.f = cmd_show_handler,
+		.data = NULL,
+		.help_str = "Show a variable value",
+		.tokens = {
+				(void *) &cmd_show_verb,
+				(void *) &cmd_show_variable,
+				NULL,
+		},
+};
+
+
+cmdline_parse_ctx_t qwctl_ctx[] = {
+		(cmdline_parse_inst_t *)&cmd_help,
+		(cmdline_parse_inst_t *)&cmd_set,
+		(cmdline_parse_inst_t *)&cmd_show,
+		NULL,
+};
diff --git a/src/seastar/dpdk/examples/quota_watermark/qwctl/commands.h b/src/seastar/dpdk/examples/quota_watermark/qwctl/commands.h
new file mode 100644
index 00000000..c010941d
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qwctl/commands.h
@@ -0,0 +1,41 @@
+/*-
+ *   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 _COMMANDS_H_
+#define _COMMANDS_H_
+
+#include <cmdline_parse.h>
+
+extern cmdline_parse_ctx_t qwctl_ctx[];
+
+#endif /* _COMMANDS_H_ */
diff --git a/src/seastar/dpdk/examples/quota_watermark/qwctl/qwctl.c b/src/seastar/dpdk/examples/quota_watermark/qwctl/qwctl.c
new file mode 100644
index 00000000..18ec17a1
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qwctl/qwctl.c
@@ -0,0 +1,96 @@
+/*-
+ *   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 <fcntl.h>
+#include <stdio.h>
+#include <termios.h>
+#include <unistd.h>
+#include <sys/mman.h>
+
+#include <rte_eal.h>
+
+#include <rte_log.h>
+#include <rte_memzone.h>
+
+#include <cmdline_rdline.h>
+#include <cmdline_parse.h>
+#include <cmdline_socket.h>
+#include <cmdline.h>
+
+
+#include "qwctl.h"
+#include "commands.h"
+#include "../include/conf.h"
+
+
+int *quota;
+unsigned int *low_watermark;
+unsigned int *high_watermark;
+
+
+static void
+setup_shared_variables(void)
+{
+	const struct rte_memzone *qw_memzone;
+
+	qw_memzone = rte_memzone_lookup(QUOTA_WATERMARK_MEMZONE_NAME);
+	if (qw_memzone == NULL)
+		rte_exit(EXIT_FAILURE, "Couldn't find memzone\n");
+
+	quota = qw_memzone->addr;
+	low_watermark = (unsigned int *) qw_memzone->addr + 1;
+	high_watermark = (unsigned int *) qw_memzone->addr + 2;
+}
+
+int main(int argc, char **argv)
+{
+	int ret;
+	struct cmdline *cl;
+
+	rte_log_set_global_level(RTE_LOG_INFO);
+
+	ret = rte_eal_init(argc, argv);
+	if (ret < 0)
+		rte_exit(EXIT_FAILURE, "Cannot initialize EAL\n");
+
+	setup_shared_variables();
+
+	cl = cmdline_stdin_new(qwctl_ctx, "qwctl> ");
+	if (cl == NULL)
+		rte_exit(EXIT_FAILURE, "Cannot create cmdline instance\n");
+
+	cmdline_interact(cl);
+	cmdline_stdin_exit(cl);
+
+	return 0;
+}
diff --git a/src/seastar/dpdk/examples/quota_watermark/qwctl/qwctl.h b/src/seastar/dpdk/examples/quota_watermark/qwctl/qwctl.h
new file mode 100644
index 00000000..545914b3
--- /dev/null
+++ b/src/seastar/dpdk/examples/quota_watermark/qwctl/qwctl.h
@@ -0,0 +1,41 @@
+/*-
+ *   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_
+
+extern int *quota;
+extern unsigned int *low_watermark;
+extern unsigned int *high_watermark;
+
+#endif /* _MAIN_H_ */