[dpdk-dev] [PATCH v2 2/6] examples/exception_path: remove example from DPDK

[Ciara Power <ciara.power@intel.com>]

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

The example app shows the use of TUN/TAP with DPDK, but DPDK has a built-in
TAP PMD, so this example is obsolete and so can be removed.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Hemant Agrawal <hemant.agrawal@nxp.com>
---
 MAINTAINERS                                 |   3 -
 doc/guides/sample_app_ug/exception_path.rst | 281 ----------
 doc/guides/sample_app_ug/index.rst          |   1 -
 examples/Makefile                           |   1 -
 examples/exception_path/Makefile            |  57 --
 examples/exception_path/main.c              | 589 --------------------
 examples/exception_path/meson.build         |  11 -
 examples/meson.build                        |   2 +-
 8 files changed, 1 insertion(+), 944 deletions(-)
 delete mode 100644 doc/guides/sample_app_ug/exception_path.rst
 delete mode 100644 examples/exception_path/Makefile
 delete mode 100644 examples/exception_path/main.c
 delete mode 100644 examples/exception_path/meson.build

diff --git a/MAINTAINERS b/MAINTAINERS
index b3d9aaddd..330a4d77d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1427,9 +1427,6 @@ Other Example Applications
 F: examples/ethtool/
 F: doc/guides/sample_app_ug/ethtool.rst
 
-F: examples/exception_path/
-F: doc/guides/sample_app_ug/exception_path.rst
-
 M: Marko Kovacevic <marko.kovacevic@intel.com>
 F: examples/fips_validation/
 F: doc/guides/sample_app_ug/fips_validation.rst
diff --git a/doc/guides/sample_app_ug/exception_path.rst b/doc/guides/sample_app_ug/exception_path.rst
deleted file mode 100644
index a5590870c..000000000
--- a/doc/guides/sample_app_ug/exception_path.rst
+++ /dev/null
@@ -1,281 +0,0 @@
-..  SPDX-License-Identifier: BSD-3-Clause
-    Copyright(c) 2010-2014 Intel Corporation.
-
-Exception Path Sample Application
-=================================
-
-The Exception Path sample application is a simple example that demonstrates the use of the DPDK
-to set up an exception path for packets to go through the Linux* kernel.
-This is done by using virtual TAP network interfaces.
-These can be read from and written to by the DPDK application and
-appear to the kernel as a standard network interface.
-
-Overview
---------
-
-The application creates two threads for each NIC port being used.
-One thread reads from the port and writes the data unmodified to a thread-specific TAP interface.
-The second thread reads from a TAP interface and writes the data unmodified to the NIC port.
-
-The packet flow through the exception path application is as shown in the following figure.
-
-.. _figure_exception_path_example:
-
-.. figure:: img/exception_path_example.*
-
-   Packet Flow
-
-
-To make throughput measurements, kernel bridges must be setup to forward data between the bridges appropriately.
-
-Compiling the Application
--------------------------
-
-To compile the sample application see :doc:`compiling`.
-
-The application is located in the ``exception_path`` sub-directory.
-
-Running the Application
------------------------
-
-The application requires a number of command line options:
-
-.. code-block:: console
-
-    .build/exception_path [EAL options] -- -p PORTMASK -i IN_CORES -o OUT_CORES
-
-where:
-
-*   -p PORTMASK: A hex bitmask of ports to use
-
-*   -i IN_CORES: A hex bitmask of cores which read from NIC
-
-*   -o OUT_CORES: A hex bitmask of cores which write to NIC
-
-Refer to the *DPDK Getting Started Guide* for general information on running applications
-and the Environment Abstraction Layer (EAL) options.
-
-The number of bits set in each bitmask must be the same.
-The coremask -c or the corelist -l parameter of the EAL options should include IN_CORES and OUT_CORES.
-The same bit must not be set in IN_CORES and OUT_CORES.
-The affinities between ports and cores are set beginning with the least significant bit of each mask, that is,
-the port represented by the lowest bit in PORTMASK is read from by the core represented by the lowest bit in IN_CORES,
-and written to by the core represented by the lowest bit in OUT_CORES.
-
-For example to run the application with two ports and four cores:
-
-.. code-block:: console
-
-    ./build/exception_path -l 0-3 -n 4 -- -p 3 -i 3 -o c
-
-Getting Statistics
-~~~~~~~~~~~~~~~~~~
-
-While the application is running, statistics on packets sent and
-received can be displayed by sending the SIGUSR1 signal to the application from another terminal:
-
-.. code-block:: console
-
-    killall -USR1 exception_path
-
-The statistics can be reset by sending a SIGUSR2 signal in a similar way.
-
-Explanation
------------
-
-The following sections provide some explanation of the code.
-
-Initialization
-~~~~~~~~~~~~~~
-
-Setup of the mbuf pool, driver and queues is similar to the setup done in the :ref:`l2_fwd_app_real_and_virtual`.
-In addition, the TAP interfaces must also be created.
-A TAP interface is created for each lcore that is being used.
-The code for creating the TAP interface is as follows:
-
-.. code-block:: c
-
-    /*
-     *   Create a tap network interface, or use existing one with same name.
-     *   If name[0]='\0' then a name is automatically assigned and returned in name.
-     */
-
-    static int tap_create(char *name)
-    {
-        struct ifreq ifr;
-        int fd, ret;
-
-        fd = open("/dev/net/tun", O_RDWR);
-        if (fd < 0)
-            return fd;
-
-        memset(&ifr, 0, sizeof(ifr));
-
-        /* TAP device without packet information */
-
-        ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
-        if (name && *name)
-            rte_snprinf(ifr.ifr_name, IFNAMSIZ, name);
-
-        ret = ioctl(fd, TUNSETIFF, (void *) &ifr);
-
-        if (ret < 0) {
-            close(fd);
-            return ret;
-
-        }
-
-        if (name)
-            snprintf(name, IFNAMSIZ, ifr.ifr_name);
-
-        return fd;
-    }
-
-The other step in the initialization process that is unique to this sample application
-is the association of each port with two cores:
-
-*   One core to read from the port and write to a TAP interface
-
-*   A second core to read from a TAP interface and write to the port
-
-This is done using an array called port_ids[], which is indexed by the lcore IDs.
-The population of this array is shown below:
-
-.. code-block:: c
-
-    tx_port = 0;
-    rx_port = 0;
-
-    RTE_LCORE_FOREACH(i) {
-        if (input_cores_mask & (1ULL << i)) {
-            /* Skip ports that are not enabled */
-            while ((ports_mask & (1 << rx_port)) == 0) {
-                rx_port++;
-                if (rx_port > (sizeof(ports_mask) * 8))
-                    goto fail; /* not enough ports */
-            }
-            port_ids[i] = rx_port++;
-        } else if (output_cores_mask & (1ULL << i)) {
-            /* Skip ports that are not enabled */
-            while ((ports_mask & (1 << tx_port)) == 0) {
-                tx_port++;
-                if (tx_port > (sizeof(ports_mask) * 8))
-                   goto fail; /* not enough ports */
-            }
-            port_ids[i] = tx_port++;
-        }
-   }
-
-Packet Forwarding
-~~~~~~~~~~~~~~~~~
-
-After the initialization steps are complete, the main_loop() function is run on each lcore.
-This function first checks the lcore_id against the user provided input_cores_mask and output_cores_mask to see
-if this core is reading from or writing to a TAP interface.
-
-For the case that reads from a NIC port, the packet reception is the same as in the L2 Forwarding sample application
-(see :ref:`l2_fwd_app_rx_tx_packets`).
-The packet transmission is done by calling write() with the file descriptor of the appropriate TAP interface
-and then explicitly freeing the mbuf back to the pool.
-
-..  code-block:: c
-
-    /* Loop forever reading from NIC and writing to tap */
-
-    for (;;) {
-        struct rte_mbuf *pkts_burst[PKT_BURST_SZ];
-        unsigned i;
-
-        const unsigned nb_rx = rte_eth_rx_burst(port_ids[lcore_id], 0, pkts_burst, PKT_BURST_SZ);
-
-        lcore_stats[lcore_id].rx += nb_rx;
-
-        for (i = 0; likely(i < nb_rx); i++) {
-            struct rte_mbuf *m = pkts_burst[i];
-            int ret = write(tap_fd, rte_pktmbuf_mtod(m, void*),
-
-            rte_pktmbuf_data_len(m));
-            rte_pktmbuf_free(m);
-            if (unlikely(ret<0))
-                lcore_stats[lcore_id].dropped++;
-            else
-                lcore_stats[lcore_id].tx++;
-        }
-    }
-
-For the other case that reads from a TAP interface and writes to a NIC port,
-packets are retrieved by doing a read() from the file descriptor of the appropriate TAP interface.
-This fills in the data into the mbuf, then other fields are set manually.
-The packet can then be transmitted as normal.
-
-.. code-block:: c
-
-    /* Loop forever reading from tap and writing to NIC */
-
-    for (;;) {
-        int ret;
-        struct rte_mbuf *m = rte_pktmbuf_alloc(pktmbuf_pool);
-
-        if (m == NULL)
-            continue;
-
-        ret = read(tap_fd, m->pkt.data, MAX_PACKET_SZ); lcore_stats[lcore_id].rx++;
-        if (unlikely(ret < 0)) {
-            FATAL_ERROR("Reading from %s interface failed", tap_name);
-        }
-
-        m->pkt.nb_segs = 1;
-        m->pkt.next = NULL;
-        m->pkt.data_len = (uint16_t)ret;
-
-        ret = rte_eth_tx_burst(port_ids[lcore_id], 0, &m, 1);
-        if (unlikely(ret < 1)) {
-            rte_pktmuf_free(m);
-            lcore_stats[lcore_id].dropped++;
-        }
-        else {
-            lcore_stats[lcore_id].tx++;
-        }
-    }
-
-To set up loops for measuring throughput, TAP interfaces can be connected using bridging.
-The steps to do this are described in the section that follows.
-
-Managing TAP Interfaces and Bridges
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The Exception Path sample application creates TAP interfaces with names of the format tap_dpdk_nn,
-where nn is the lcore ID. These TAP interfaces need to be configured for use:
-
-.. code-block:: console
-
-    ifconfig tap_dpdk_00 up
-
-To set up a bridge between two interfaces so that packets sent to one interface can be read from another,
-use the brctl tool:
-
-.. code-block:: console
-
-    brctl addbr "br0"
-    brctl addif br0 tap_dpdk_00
-    brctl addif br0 tap_dpdk_03
-    ifconfig br0 up
-
-The TAP interfaces created by this application exist only when the application is running,
-so the steps above need to be repeated each time the application is run.
-To avoid this, persistent TAP interfaces can be created using openvpn:
-
-.. code-block:: console
-
-    openvpn --mktun --dev tap_dpdk_00
-
-If this method is used, then the steps above have to be done only once and
-the same TAP interfaces can be reused each time the application is run.
-To remove bridges and persistent TAP interfaces, the following commands are used:
-
-.. code-block:: console
-
-    ifconfig br0 down
-    brctl delbr br0
-    openvpn --rmtun --dev tap_dpdk_00
-
diff --git a/doc/guides/sample_app_ug/index.rst b/doc/guides/sample_app_ug/index.rst
index f23f8f59e..076346a60 100644
--- a/doc/guides/sample_app_ug/index.rst
+++ b/doc/guides/sample_app_ug/index.rst
@@ -12,7 +12,6 @@ Sample Applications User Guides
     compiling
     cmd_line
     ethtool
-    exception_path
     hello_world
     skeleton
     rxtx_callbacks
diff --git a/examples/Makefile b/examples/Makefile
index de11dd487..c756497d1 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -17,7 +17,6 @@ ifeq ($(CONFIG_RTE_LIBRTE_POWER),y)
 DIRS-$(CONFIG_RTE_LIBRTE_DISTRIBUTOR) += distributor
 endif
 DIRS-y += ethtool
-DIRS-y += exception_path
 DIRS-$(CONFIG_RTE_LIBRTE_EFD) += server_node_efd
 DIRS-$(CONFIG_RTE_LIBRTE_CRYPTODEV) += fips_validation
 DIRS-$(CONFIG_RTE_LIBRTE_FLOW_CLASSIFY) += flow_classify
diff --git a/examples/exception_path/Makefile b/examples/exception_path/Makefile
deleted file mode 100644
index 90c7f133a..000000000
--- a/examples/exception_path/Makefile
+++ /dev/null
@@ -1,57 +0,0 @@
-# SPDX-License-Identifier: BSD-3-Clause
-# Copyright(c) 2010-2014 Intel Corporation
-
-# binary name
-APP = exception_path
-
-# all source are stored in SRCS-y
-SRCS-y := main.c
-
-# Build using pkg-config variables if possible
-ifeq ($(shell pkg-config --exists libdpdk && echo 0),0)
-
-all: shared
-.PHONY: shared static
-shared: build/$(APP)-shared
-	ln -sf $(APP)-shared build/$(APP)
-static: build/$(APP)-static
-	ln -sf $(APP)-static build/$(APP)
-
-PKGCONF=pkg-config --define-prefix
-
-PC_FILE := $(shell $(PKGCONF) --path libdpdk)
-CFLAGS += -O3 $(shell $(PKGCONF) --cflags libdpdk)
-LDFLAGS_SHARED = $(shell $(PKGCONF) --libs libdpdk)
-LDFLAGS_STATIC = -Wl,-Bstatic $(shell $(PKGCONF) --static --libs libdpdk)
-
-build/$(APP)-shared: $(SRCS-y) Makefile $(PC_FILE) | build
-	$(CC) $(CFLAGS) $(SRCS-y) -o $@ $(LDFLAGS) $(LDFLAGS_SHARED)
-
-build/$(APP)-static: $(SRCS-y) Makefile $(PC_FILE) | build
-	$(CC) $(CFLAGS) $(SRCS-y) -o $@ $(LDFLAGS) $(LDFLAGS_STATIC)
-
-build:
-	@mkdir -p $@
-
-.PHONY: clean
-clean:
-	rm -f build/$(APP) build/$(APP)-static build/$(APP)-shared
-	test -d build && rmdir -p build || true
-
-else
-
-ifeq ($(RTE_SDK),)
-$(error "Please define RTE_SDK environment variable")
-endif
-
-# Default target, detect a build directory, by looking for a path with a .config
-RTE_TARGET ?= $(notdir $(abspath $(dir $(firstword $(wildcard $(RTE_SDK)/*/.config)))))
-
-include $(RTE_SDK)/mk/rte.vars.mk
-
-CFLAGS += -O3
-CFLAGS += $(WERROR_FLAGS)
-
-include $(RTE_SDK)/mk/rte.extapp.mk
-
-endif
diff --git a/examples/exception_path/main.c b/examples/exception_path/main.c
deleted file mode 100644
index 0d79e5a24..000000000
--- a/examples/exception_path/main.c
+++ /dev/null
@@ -1,589 +0,0 @@
-/* SPDX-License-Identifier: BSD-3-Clause
- * Copyright(c) 2010-2014 Intel Corporation
- */
-
-#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 <net/if.h>
-#ifdef RTE_EXEC_ENV_LINUX
-#include <linux/if_tun.h>
-#endif
-#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_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_debug.h>
-#include <rte_ether.h>
-#include <rte_ethdev.h>
-#include <rte_mempool.h>
-#include <rte_mbuf.h>
-#include <rte_string_fns.h>
-#include <rte_cycles.h>
-
-#ifndef APP_MAX_LCORE
-#if (RTE_MAX_LCORE > 64)
-#define APP_MAX_LCORE 64
-#else
-#define APP_MAX_LCORE RTE_MAX_LCORE
-#endif
-#endif
-
-/* Macros for printing using RTE_LOG */
-#define RTE_LOGTYPE_APP RTE_LOGTYPE_USER1
-#define FATAL_ERROR(fmt, args...)       rte_exit(EXIT_FAILURE, fmt "\n", ##args)
-#define PRINT_INFO(fmt, args...)        RTE_LOG(INFO, APP, fmt "\n", ##args)
-
-/* Max ports than can be used (each port is associated with two lcores) */
-#define MAX_PORTS               (APP_MAX_LCORE / 2)
-
-/* 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
-
-/* 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                  1024
-
-/* Number of TX ring descriptors */
-#define NB_TXD                  1024
-
-/*
- * RX and TX Prefetch, Host, and Write-back threshold values should be
- * carefully set for optimal performance. Consult the network
- * controller's datasheet and supporting DPDK documentation for guidance
- * on how these parameters should be set.
- */
-
-/* Options for configuring ethernet port */
-static struct rte_eth_conf port_conf = {
-	.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;
-
-/* Mask of cores that read from NIC and write to tap */
-static uint64_t input_cores_mask = 0;
-
-/* Mask of cores that read from tap and write to NIC */
-static uint64_t output_cores_mask = 0;
-
-/* Array storing port_id that is associated with each lcore */
-static uint16_t port_ids[APP_MAX_LCORE];
-
-/* Structure type for recording lcore-specific stats */
-struct stats {
-	uint64_t rx;
-	uint64_t tx;
-	uint64_t dropped;
-} __rte_cache_aligned;
-
-/* Array of lcore-specific stats */
-static struct stats lcore_stats[APP_MAX_LCORE];
-
-/* Print out statistics on packets handled */
-static void
-print_stats(void)
-{
-	unsigned i;
-
-	printf("\n**Exception-Path example application statistics**\n"
-	       "=======  ======  ============  ============  ===============\n"
-	       " Lcore    Port            RX            TX    Dropped on TX\n"
-	       "-------  ------  ------------  ------------  ---------------\n");
-	RTE_LCORE_FOREACH(i) {
-		/* limit ourselves to application supported cores only */
-		if (i >= APP_MAX_LCORE)
-			break;
-		printf("%6u %7u %13"PRIu64" %13"PRIu64" %16"PRIu64"\n",
-		       i, (unsigned)port_ids[i],
-		       lcore_stats[i].rx, lcore_stats[i].tx,
-		       lcore_stats[i].dropped);
-	}
-	printf("=======  ======  ============  ============  ===============\n");
-}
-
-/* Custom handling of signals to handle stats */
-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(&lcore_stats, 0, sizeof(lcore_stats));
-		printf("\n**Statistics have been reset**\n");
-		return;
-	}
-}
-
-#ifdef RTE_EXEC_ENV_LINUX
-/*
- * Create a tap network interface, or use existing one with same name.
- * If name[0]='\0' then a name is automatically assigned and returned in name.
- */
-static int tap_create(char *name)
-{
-	struct ifreq ifr;
-	int fd, ret;
-
-	fd = open("/dev/net/tun", O_RDWR);
-	if (fd < 0)
-		return fd;
-
-	memset(&ifr, 0, sizeof(ifr));
-
-	/* TAP device without packet information */
-	ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
-
-	if (name && *name)
-		strlcpy(ifr.ifr_name, name, IFNAMSIZ);
-
-	ret = ioctl(fd, TUNSETIFF, (void *) &ifr);
-	if (ret < 0) {
-		close(fd);
-		return ret;
-	}
-
-	if (name)
-		strlcpy(name, ifr.ifr_name, IFNAMSIZ);
-
-	return fd;
-}
-#else
-/*
- * Find a free tap network interface, or create a new one.
- * The name is automatically assigned and returned in name.
- */
-static int tap_create(char *name)
-{
-	int i, fd = -1;
-	char devname[PATH_MAX];
-
-	for (i = 0; i < 255; i++) {
-		snprintf(devname, sizeof(devname), "/dev/tap%d", i);
-		fd = open(devname, O_RDWR);
-		if (fd >= 0 || errno != EBUSY)
-			break;
-	}
-
-	if (name)
-		snprintf(name, IFNAMSIZ, "tap%d", i);
-
-	return fd;
-}
-#endif
-
-/* Main processing loop */
-static int
-main_loop(__attribute__((unused)) void *arg)
-{
-	const unsigned lcore_id = rte_lcore_id();
-	char tap_name[IFNAMSIZ];
-	int tap_fd;
-
-	if ((1ULL << lcore_id) & input_cores_mask) {
-		/* Create new tap interface */
-		snprintf(tap_name, IFNAMSIZ, "tap_dpdk_%.2u", lcore_id);
-		tap_fd = tap_create(tap_name);
-		if (tap_fd < 0)
-			FATAL_ERROR("Could not create tap interface \"%s\" (%d)",
-					tap_name, tap_fd);
-
-		PRINT_INFO("Lcore %u is reading from port %u and writing to %s",
-		           lcore_id, (unsigned)port_ids[lcore_id], tap_name);
-		fflush(stdout);
-		/* Loop forever reading from NIC and writing to tap */
-		for (;;) {
-			struct rte_mbuf *pkts_burst[PKT_BURST_SZ];
-			unsigned i;
-			const unsigned nb_rx =
-					rte_eth_rx_burst(port_ids[lcore_id], 0,
-					    pkts_burst, PKT_BURST_SZ);
-			lcore_stats[lcore_id].rx += nb_rx;
-			for (i = 0; likely(i < nb_rx); i++) {
-				struct rte_mbuf *m = pkts_burst[i];
-				/* Ignore return val from write() */
-				int ret = write(tap_fd,
-				                rte_pktmbuf_mtod(m, void*),
-				                rte_pktmbuf_data_len(m));
-				rte_pktmbuf_free(m);
-				if (unlikely(ret < 0))
-					lcore_stats[lcore_id].dropped++;
-				else
-					lcore_stats[lcore_id].tx++;
-			}
-		}
-	}
-	else if ((1ULL << lcore_id) & output_cores_mask) {
-		/* Create new tap interface */
-		snprintf(tap_name, IFNAMSIZ, "tap_dpdk_%.2u", lcore_id);
-		tap_fd = tap_create(tap_name);
-		if (tap_fd < 0)
-			FATAL_ERROR("Could not create tap interface \"%s\" (%d)",
-					tap_name, tap_fd);
-
-		PRINT_INFO("Lcore %u is reading from %s and writing to port %u",
-		           lcore_id, tap_name, (unsigned)port_ids[lcore_id]);
-		fflush(stdout);
-		/* Loop forever reading from tap and writing to NIC */
-		for (;;) {
-			int ret;
-			struct rte_mbuf *m = rte_pktmbuf_alloc(pktmbuf_pool);
-			if (m == NULL)
-				continue;
-
-			ret = read(tap_fd, rte_pktmbuf_mtod(m, void *),
-				MAX_PACKET_SZ);
-			lcore_stats[lcore_id].rx++;
-			if (unlikely(ret < 0)) {
-				FATAL_ERROR("Reading from %s interface failed",
-				            tap_name);
-			}
-			m->nb_segs = 1;
-			m->next = NULL;
-			m->pkt_len = (uint16_t)ret;
-			m->data_len = (uint16_t)ret;
-			ret = rte_eth_tx_burst(port_ids[lcore_id], 0, &m, 1);
-			if (unlikely(ret < 1)) {
-				rte_pktmbuf_free(m);
-				lcore_stats[lcore_id].dropped++;
-			}
-			else {
-				lcore_stats[lcore_id].tx++;
-			}
-		}
-	}
-	else {
-		PRINT_INFO("Lcore %u has nothing to do", lcore_id);
-		return 0;
-	}
-	/*
-	 * Tap file is closed automatically when program exits. Putting close()
-	 * here will cause the compiler to give an error about unreachable code.
-	 */
-}
-
-/* Display usage instructions */
-static void
-print_usage(const char *prgname)
-{
-	PRINT_INFO("\nUsage: %s [EAL options] -- -p PORTMASK -i IN_CORES -o OUT_CORES\n"
-	           "    -p PORTMASK: hex bitmask of ports to use\n"
-	           "    -i IN_CORES: hex bitmask of cores which read from NIC\n"
-	           "    -o OUT_CORES: hex bitmask of cores which write to NIC",
-	           prgname);
-}
-
-/* Convert string to unsigned number. 0 is returned if error occurs */
-static uint64_t
-parse_unsigned(const char *portmask)
-{
-	char *end = NULL;
-	uint64_t num;
-
-	num = strtoull(portmask, &end, 16);
-	if ((portmask[0] == '\0') || (end == NULL) || (*end != '\0'))
-		return 0;
-
-	return (uint64_t)num;
-}
-
-/* Record affinities between ports and lcores in global port_ids[] array */
-static void
-setup_port_lcore_affinities(void)
-{
-	unsigned long i;
-	uint16_t tx_port = 0;
-	uint16_t rx_port = 0;
-
-	/* Setup port_ids[] array, and check masks were ok */
-	for (i = 0; i < APP_MAX_LCORE; i++) {
-		if (!rte_lcore_is_enabled(i))
-			continue;
-		if (input_cores_mask & (1ULL << i)) {
-			/* Skip ports that are not enabled */
-			while ((ports_mask & (1 << rx_port)) == 0) {
-				rx_port++;
-				if (rx_port > (sizeof(ports_mask) * 8))
-					goto fail; /* not enough ports */
-			}
-
-			port_ids[i] = rx_port++;
-		} else if (output_cores_mask & (1ULL << (i & 0x3f))) {
-			/* Skip ports that are not enabled */
-			while ((ports_mask & (1 << tx_port)) == 0) {
-				tx_port++;
-				if (tx_port > (sizeof(ports_mask) * 8))
-					goto fail; /* not enough ports */
-			}
-
-			port_ids[i] = tx_port++;
-		}
-	}
-
-	if (rx_port != tx_port)
-		goto fail; /* uneven number of cores in masks */
-
-	if (ports_mask & (~((1 << rx_port) - 1)))
-		goto fail; /* unused ports */
-
-	return;
-fail:
-	FATAL_ERROR("Invalid core/port masks specified on command line");
-}
-
-/* Parse the arguments given in the command line of the application */
-static void
-parse_args(int argc, char **argv)
-{
-	int opt;
-	const char *prgname = argv[0];
-
-	/* Disable printing messages within getopt() */
-	opterr = 0;
-
-	/* Parse command line */
-	while ((opt = getopt(argc, argv, "i:o:p:")) != EOF) {
-		switch (opt) {
-		case 'i':
-			input_cores_mask = parse_unsigned(optarg);
-			break;
-		case 'o':
-			output_cores_mask = parse_unsigned(optarg);
-			break;
-		case 'p':
-			ports_mask = parse_unsigned(optarg);
-			break;
-		default:
-			print_usage(prgname);
-			FATAL_ERROR("Invalid option specified");
-		}
-	}
-
-	/* Check that options were parsed ok */
-	if (input_cores_mask == 0) {
-		print_usage(prgname);
-		FATAL_ERROR("IN_CORES not specified correctly");
-	}
-	if (output_cores_mask == 0) {
-		print_usage(prgname);
-		FATAL_ERROR("OUT_CORES not specified correctly");
-	}
-	if (ports_mask == 0) {
-		print_usage(prgname);
-		FATAL_ERROR("PORTMASK not specified correctly");
-	}
-
-	setup_port_lcore_affinities();
-}
-
-/* Initialise a single port on an Ethernet device */
-static void
-init_port(uint16_t port)
-{
-	int ret;
-	uint16_t nb_rxd = NB_RXD;
-	uint16_t nb_txd = NB_TXD;
-	struct rte_eth_dev_info dev_info;
-	struct rte_eth_rxconf rxq_conf;
-	struct rte_eth_txconf txq_conf;
-	struct rte_eth_conf local_port_conf = port_conf;
-
-	/* Initialise device and RX/TX queues */
-	PRINT_INFO("Initialising port %u ...", port);
-	fflush(stdout);
-	rte_eth_dev_info_get(port, &dev_info);
-	if (dev_info.tx_offload_capa & DEV_TX_OFFLOAD_MBUF_FAST_FREE)
-		local_port_conf.txmode.offloads |=
-			DEV_TX_OFFLOAD_MBUF_FAST_FREE;
-	ret = rte_eth_dev_configure(port, 1, 1, &local_port_conf);
-	if (ret < 0)
-		FATAL_ERROR("Could not configure port%u (%d)", port, ret);
-
-	ret = rte_eth_dev_adjust_nb_rx_tx_desc(port, &nb_rxd, &nb_txd);
-	if (ret < 0)
-		FATAL_ERROR("Could not adjust number of descriptors for port%u (%d)",
-			    port, ret);
-
-	rxq_conf = dev_info.default_rxconf;
-	rxq_conf.offloads = local_port_conf.rxmode.offloads;
-	ret = rte_eth_rx_queue_setup(port, 0, nb_rxd,
-				rte_eth_dev_socket_id(port),
-				&rxq_conf,
-				pktmbuf_pool);
-	if (ret < 0)
-		FATAL_ERROR("Could not setup up RX queue for port%u (%d)",
-				port, ret);
-
-	txq_conf = dev_info.default_txconf;
-	txq_conf.offloads = local_port_conf.txmode.offloads;
-	ret = rte_eth_tx_queue_setup(port, 0, nb_txd,
-				rte_eth_dev_socket_id(port),
-				&txq_conf);
-	if (ret < 0)
-		FATAL_ERROR("Could not setup up TX queue for port%u (%d)",
-				port, ret);
-
-	ret = rte_eth_dev_start(port);
-	if (ret < 0)
-		FATAL_ERROR("Could not start port%u (%d)", port, ret);
-
-	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(uint32_t port_mask)
-{
-#define CHECK_INTERVAL 100 /* 100ms */
-#define MAX_CHECK_TIME 90 /* 9s (90 * 100ms) in total */
-	uint16_t portid;
-	uint8_t count, all_ports_up, print_flag = 0;
-	struct rte_eth_link link;
-
-	printf("\nChecking link status");
-	fflush(stdout);
-	for (count = 0; count <= MAX_CHECK_TIME; count++) {
-		all_ports_up = 1;
-		RTE_ETH_FOREACH_DEV(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",
-						portid, link.link_speed,
-				(link.link_duplex == ETH_LINK_FULL_DUPLEX) ?
-					("full-duplex") : ("half-duplex\n"));
-				else
-					printf("Port %d Link Down\n", 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");
-		}
-	}
-}
-
-/* Initialise ports/queues etc. and start main loop on each core */
-int
-main(int argc, char** argv)
-{
-	int ret;
-	unsigned i,high_port;
-	uint16_t nb_sys_ports, port;
-
-	/* Associate signal_hanlder function with USR signals */
-	signal(SIGUSR1, signal_handler);
-	signal(SIGUSR2, signal_handler);
-
-	/* Initialise EAL */
-	ret = rte_eal_init(argc, argv);
-	if (ret < 0)
-		FATAL_ERROR("Could not initialise EAL (%d)", ret);
-	argc -= ret;
-	argv += ret;
-
-	/* Parse application arguments (after the EAL ones) */
-	parse_args(argc, argv);
-
-	/* 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) {
-		FATAL_ERROR("Could not initialise mbuf pool");
-		return -1;
-	}
-
-	/* Get number of ports found in scan */
-	nb_sys_ports = rte_eth_dev_count_avail();
-	if (nb_sys_ports == 0)
-		FATAL_ERROR("No supported Ethernet device found");
-	/* Find highest port set in portmask */
-	for (high_port = (sizeof(ports_mask) * 8) - 1;
-			(high_port != 0) && !(ports_mask & (1 << high_port));
-			high_port--)
-		; /* empty body */
-	if (high_port > nb_sys_ports)
-		FATAL_ERROR("Port mask requires more ports than available");
-
-	/* Initialise each port */
-	RTE_ETH_FOREACH_DEV(port) {
-		/* Skip ports that are not enabled */
-		if ((ports_mask & (1 << port)) == 0) {
-			continue;
-		}
-		init_port(port);
-	}
-	check_all_ports_link_status(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;
-	}
-
-	return 0;
-}
diff --git a/examples/exception_path/meson.build b/examples/exception_path/meson.build
deleted file mode 100644
index c34e11e36..000000000
--- a/examples/exception_path/meson.build
+++ /dev/null
@@ -1,11 +0,0 @@
-# SPDX-License-Identifier: BSD-3-Clause
-# Copyright(c) 2017 Intel Corporation
-
-# meson file, for building this example as part of a main DPDK build.
-#
-# To build this example as a standalone application with an already-installed
-# DPDK instance, use 'make'
-
-sources = files(
-	'main.c'
-)
diff --git a/examples/meson.build b/examples/meson.build
index a046b74ad..4663d9dea 100644
--- a/examples/meson.build
+++ b/examples/meson.build
@@ -13,7 +13,7 @@ all_examples = [
 	'bbdev_app', 'bond',
 	'bpf', 'cmdline',
 	'distributor', 'ethtool',
-	'eventdev_pipeline', 'exception_path',
+	'eventdev_pipeline',
 	'fips_validation', 'flow_classify',
 	'flow_filtering', 'helloworld',
 	'ip_fragmentation', 'ip_pipeline',
-- 
2.17.1