[PATCH 2/3] test: add event dispatcher test suite

["Mattias Rönnblom" <mattias.ronnblom@ericsson.com>]

Add unit tests for the event dispatcher.

--

PATCH:
 o Extend test to cover often-used handler optimization feature.
RFC v4:
 o Adapt to non-const events in process function prototype.

Signed-off-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
---
 app/test/meson.build             |   1 +
 app/test/test_event_dispatcher.c | 861 +++++++++++++++++++++++++++++++
 2 files changed, 862 insertions(+)
 create mode 100644 app/test/test_event_dispatcher.c

diff --git a/app/test/meson.build b/app/test/meson.build
index b9b5432496..fac3b6b88b 100644
--- a/app/test/meson.build
+++ b/app/test/meson.build
@@ -50,6 +50,7 @@ test_sources = files(
         'test_errno.c',
         'test_ethdev_link.c',
         'test_event_crypto_adapter.c',
+        'test_event_dispatcher.c',
         'test_event_eth_rx_adapter.c',
         'test_event_ring.c',
         'test_event_timer_adapter.c',
diff --git a/app/test/test_event_dispatcher.c b/app/test/test_event_dispatcher.c
new file mode 100644
index 0000000000..356ef8df44
--- /dev/null
+++ b/app/test/test_event_dispatcher.c
@@ -0,0 +1,861 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2023 Ericsson AB
+ */
+
+#include "test.h"
+
+#include <stdatomic.h>
+
+#include <rte_bus_vdev.h>
+#include <rte_event_dispatcher.h>
+#include <rte_eventdev.h>
+#include <rte_random.h>
+#include <rte_service.h>
+
+#define NUM_WORKERS 3
+
+#define NUM_PORTS (NUM_WORKERS + 1)
+#define WORKER_PORT_ID(worker_idx) (worker_idx)
+#define DRIVER_PORT_ID (NUM_PORTS - 1)
+
+#define NUM_SERVICE_CORES NUM_WORKERS
+
+/* Eventdev */
+#define NUM_QUEUES 8
+#define LAST_QUEUE_ID (NUM_QUEUES - 1)
+#define MAX_EVENTS 4096
+#define NEW_EVENT_THRESHOLD (MAX_EVENTS / 2)
+#define DEQUEUE_BURST_SIZE 32
+#define ENQUEUE_BURST_SIZE 32
+
+#define NUM_EVENTS 10000000
+#define NUM_FLOWS 16
+
+#define DSW_VDEV "event_dsw0"
+
+struct app_queue {
+	uint8_t queue_id;
+	uint64_t sn[NUM_FLOWS];
+	int dispatcher_reg_id;
+};
+
+struct test_app {
+	uint8_t event_dev_id;
+	uint8_t dispatcher_id;
+	uint32_t dispatcher_service_id;
+
+	unsigned int service_lcores[NUM_SERVICE_CORES];
+
+	int never_match_reg_id;
+	uint64_t never_match_count;
+	uint64_t never_process_count;
+
+	struct app_queue queues[NUM_QUEUES];
+
+	bool running;
+
+	atomic_int completed_events;
+	atomic_int errors;
+};
+
+#define RETURN_ON_ERROR(rc) \
+	do {					\
+		if (rc != TEST_SUCCESS)		\
+			return rc;		\
+	} while (0)
+
+static struct test_app *
+test_app_create(void)
+{
+	int i;
+	struct test_app *app;
+
+	app = calloc(1, sizeof(struct test_app));
+
+	if (app == NULL)
+		return NULL;
+
+	for (i = 0; i < NUM_QUEUES; i++)
+		app->queues[i].queue_id = i;
+
+	return app;
+}
+
+static void
+test_app_free(struct test_app *app)
+{
+	free(app);
+}
+
+static int
+test_app_create_vdev(struct test_app *app)
+{
+	int rc;
+
+	rc = rte_vdev_init(DSW_VDEV, NULL);
+	if (rc < 0)
+		return TEST_SKIPPED;
+
+	rc = rte_event_dev_get_dev_id(DSW_VDEV);
+
+	app->event_dev_id = (uint8_t)rc;
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_destroy_vdev(struct test_app *app)
+{
+	int rc;
+
+	rc = rte_event_dev_close(app->event_dev_id);
+	TEST_ASSERT_SUCCESS(rc, "Error while closing event device");
+
+	rc = rte_vdev_uninit(DSW_VDEV);
+	TEST_ASSERT_SUCCESS(rc, "Error while uninitializing virtual device");
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_setup_event_dev(struct test_app *app)
+{
+	int rc;
+	int i;
+
+	rc = test_app_create_vdev(app);
+	if (rc < 0)
+		return rc;
+
+	struct rte_event_dev_config config = {
+		.nb_event_queues = NUM_QUEUES,
+		.nb_event_ports = NUM_PORTS,
+		.nb_events_limit = MAX_EVENTS,
+		.nb_event_queue_flows = 64,
+		.nb_event_port_dequeue_depth = DEQUEUE_BURST_SIZE,
+		.nb_event_port_enqueue_depth = ENQUEUE_BURST_SIZE
+	};
+
+	rc = rte_event_dev_configure(app->event_dev_id, &config);
+
+	TEST_ASSERT_SUCCESS(rc, "Unable to configure event device");
+
+	struct rte_event_queue_conf queue_config = {
+		.priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
+		.schedule_type = RTE_SCHED_TYPE_ATOMIC,
+		.nb_atomic_flows = 64
+	};
+
+	for (i = 0; i < NUM_QUEUES; i++) {
+		uint8_t queue_id = i;
+
+		rc = rte_event_queue_setup(app->event_dev_id, queue_id,
+					   &queue_config);
+
+		TEST_ASSERT_SUCCESS(rc, "Unable to setup queue %d", queue_id);
+	}
+
+	struct rte_event_port_conf port_config = {
+		.new_event_threshold = NEW_EVENT_THRESHOLD,
+		.dequeue_depth = DEQUEUE_BURST_SIZE,
+		.enqueue_depth = ENQUEUE_BURST_SIZE
+	};
+
+	for (i = 0; i < NUM_PORTS; i++) {
+		uint8_t event_port_id = i;
+
+		rc = rte_event_port_setup(app->event_dev_id, event_port_id,
+					  &port_config);
+		TEST_ASSERT_SUCCESS(rc, "Failed to create event port %d",
+				    event_port_id);
+
+		if (event_port_id == DRIVER_PORT_ID)
+			continue;
+
+		rc = rte_event_port_link(app->event_dev_id, event_port_id,
+					 NULL, NULL, 0);
+
+		TEST_ASSERT_EQUAL(rc, NUM_QUEUES, "Failed to link port %d",
+				  event_port_id);
+	}
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_teardown_event_dev(struct test_app *app)
+{
+	return test_app_destroy_vdev(app);
+}
+
+static int
+test_app_start_event_dev(struct test_app *app)
+{
+	int rc;
+
+	rc = rte_event_dev_start(app->event_dev_id);
+	TEST_ASSERT_SUCCESS(rc, "Unable to start event device");
+
+	return TEST_SUCCESS;
+}
+
+static void
+test_app_stop_event_dev(struct test_app *app)
+{
+	rte_event_dev_stop(app->event_dev_id);
+}
+
+static int
+test_app_create_dispatcher(struct test_app *app)
+{
+	int rc;
+
+	app->dispatcher_id = rte_rand_max(256);
+
+	rc = rte_event_dispatcher_create(app->dispatcher_id,
+					 app->event_dev_id);
+
+	TEST_ASSERT_SUCCESS(rc, "Unable to create event dispatcher");
+
+	rc = rte_event_dispatcher_service_id_get(app->dispatcher_id,
+						 &app->dispatcher_service_id);
+	TEST_ASSERT_SUCCESS(rc, "Unable to get event dispatcher service ID");
+
+	rc = rte_service_set_stats_enable(app->dispatcher_service_id, 1);
+
+	TEST_ASSERT_SUCCESS(rc, "Unable to enable event dispatcher service "
+			    "stats");
+
+	rc = rte_service_runstate_set(app->dispatcher_service_id, 1);
+	TEST_ASSERT_SUCCESS(rc, "Error disabling dispatcher service");
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_free_dispatcher(struct test_app *app)
+{
+	int rc;
+
+	rc = rte_service_runstate_set(app->dispatcher_service_id, 0);
+	TEST_ASSERT_SUCCESS(rc, "Error disabling dispatcher service");
+
+	rte_event_dispatcher_free(app->dispatcher_id);
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_bind_ports(struct test_app *app)
+{
+	int i;
+
+	for (i = 0; i < NUM_WORKERS; i++) {
+		unsigned int lcore_id = app->service_lcores[i];
+
+		int rc = rte_event_dispatcher_bind_port_to_lcore(
+			app->dispatcher_id, WORKER_PORT_ID(i),
+			DEQUEUE_BURST_SIZE, 0, lcore_id
+		);
+
+		TEST_ASSERT_SUCCESS(rc, "Unable to bind event device port %d "
+				    "to lcore %d", WORKER_PORT_ID(i),
+				    lcore_id);
+	}
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_unbind_ports(struct test_app *app)
+{
+	int i;
+
+	for (i = 0; i < NUM_WORKERS; i++) {
+		unsigned int lcore_id = app->service_lcores[i];
+
+		int rc = rte_event_dispatcher_unbind_port_from_lcore(
+			app->dispatcher_id,
+			WORKER_PORT_ID(i),
+			lcore_id
+		);
+
+		TEST_ASSERT_SUCCESS(rc, "Unable to unbind event device port %d "
+				    "from lcore %d", WORKER_PORT_ID(i),
+				    lcore_id);
+	}
+
+	return TEST_SUCCESS;
+}
+
+static bool
+match_queue(const struct rte_event *event, void *cb_data)
+{
+	uintptr_t queue_id = (uintptr_t)cb_data;
+
+	return event->queue_id == queue_id;
+}
+
+static int
+test_app_get_worker_index(struct test_app *app, unsigned int lcore_id)
+{
+	int i;
+
+	for (i = 0; i < NUM_SERVICE_CORES; i++)
+		if (app->service_lcores[i] == lcore_id)
+			return i;
+
+	return -1;
+}
+
+static int
+test_app_get_worker_port(struct test_app *app, unsigned int lcore_id)
+{
+	int worker;
+
+	worker = test_app_get_worker_index(app, lcore_id);
+
+	if (worker < 0)
+		return -1;
+
+	return WORKER_PORT_ID(worker);
+}
+
+static void
+test_app_queue_note_error(struct test_app *app)
+{
+	atomic_fetch_add_explicit(&app->errors, 1, memory_order_relaxed);
+}
+
+static void
+test_app_process_queue(uint8_t p_event_dev_id, uint8_t p_event_port_id,
+		       struct rte_event *in_events, uint16_t num,
+		       void *cb_data)
+{
+	struct app_queue *app_queue = cb_data;
+	struct test_app *app = container_of(app_queue, struct test_app,
+					    queues[app_queue->queue_id]);
+	unsigned int lcore_id = rte_lcore_id();
+	bool intermediate_queue = app_queue->queue_id != LAST_QUEUE_ID;
+	int event_port_id;
+	uint16_t i;
+	struct rte_event out_events[num];
+
+	event_port_id = test_app_get_worker_port(app, lcore_id);
+
+	if (event_port_id < 0 || p_event_dev_id != app->event_dev_id ||
+	    p_event_port_id != event_port_id) {
+		test_app_queue_note_error(app);
+		return;
+	}
+
+	for (i = 0; i < num; i++) {
+		const struct rte_event *in_event = &in_events[i];
+		struct rte_event *out_event = &out_events[i];
+		uint64_t sn = in_event->u64;
+		uint64_t expected_sn;
+
+		if (in_event->queue_id != app_queue->queue_id) {
+			test_app_queue_note_error(app);
+			return;
+		}
+
+		expected_sn = app_queue->sn[in_event->flow_id]++;
+
+		if (expected_sn != sn) {
+			test_app_queue_note_error(app);
+			return;
+		}
+
+		if (intermediate_queue)
+			*out_event = (struct rte_event) {
+				.queue_id = in_event->queue_id + 1,
+				.flow_id = in_event->flow_id,
+				.sched_type = RTE_SCHED_TYPE_ATOMIC,
+				.op = RTE_EVENT_OP_FORWARD,
+				.priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
+				.u64 = sn
+			};
+	}
+
+	if (intermediate_queue) {
+		uint16_t n = 0;
+
+		do {
+			n += rte_event_enqueue_forward_burst(p_event_dev_id,
+							     p_event_port_id,
+							     out_events + n,
+							     num - n);
+		} while (n != num);
+	} else
+		atomic_fetch_add_explicit(&app->completed_events, num,
+					  memory_order_relaxed);
+}
+
+static bool
+never_match(const struct rte_event *event __rte_unused, void *cb_data)
+{
+	uint64_t *count = cb_data;
+
+	(*count)++;
+
+	return false;
+}
+
+static void
+test_app_never_process(uint8_t event_dev_id __rte_unused,
+		       uint8_t event_port_id __rte_unused,
+		       struct rte_event *in_events __rte_unused,
+		       uint16_t num, void *cb_data)
+{
+	uint64_t *count = cb_data;
+
+	(*count) += num;
+}
+
+static int
+test_app_register_callbacks(struct test_app *app)
+{
+	int i;
+
+	app->never_match_reg_id =
+		rte_event_dispatcher_register(app->dispatcher_id,
+					      never_match,
+					      &app->never_match_count,
+					      test_app_never_process,
+					      &app->never_process_count);
+
+	TEST_ASSERT(app->never_match_reg_id >= 0, "Unable to register "
+		    "never-match handler");
+
+	for (i = 0; i < NUM_QUEUES; i++) {
+		struct app_queue *app_queue = &app->queues[i];
+		uintptr_t queue_id = app_queue->queue_id;
+		int reg_id;
+
+		reg_id = rte_event_dispatcher_register(app->dispatcher_id,
+						       match_queue,
+						       (void *)queue_id,
+						       test_app_process_queue,
+						       app_queue);
+
+		TEST_ASSERT(reg_id >= 0, "Unable to register consumer "
+			    "callback for queue %d", i);
+
+		app_queue->dispatcher_reg_id = reg_id;
+	}
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_unregister_callback(struct test_app *app, uint8_t queue_id)
+{
+	int reg_id = app->queues[queue_id].dispatcher_reg_id;
+
+	if (reg_id < 0) /* unregistered already */
+		return 0;
+
+	int rc = rte_event_dispatcher_unregister(app->dispatcher_id, reg_id);
+
+	TEST_ASSERT_SUCCESS(rc, "Unable to unregister consumer "
+			    "callback for queue %d", queue_id);
+
+	app->queues[queue_id].dispatcher_reg_id = -1;
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_unregister_callbacks(struct test_app *app)
+{
+	int i;
+
+	for (i = 0; i < NUM_QUEUES; i++) {
+		int rc;
+
+		rc = test_app_unregister_callback(app, i);
+		RETURN_ON_ERROR(rc);
+	}
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_start_dispatcher(struct test_app *app)
+{
+	int rc;
+
+	rc = rte_event_dispatcher_start(app->dispatcher_id);
+
+	TEST_ASSERT_SUCCESS(rc, "Unable to start the event dispatcher");
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_stop_dispatcher(struct test_app *app)
+{
+	int rc;
+
+	rc = rte_event_dispatcher_stop(app->dispatcher_id);
+
+	TEST_ASSERT_SUCCESS(rc, "Unable to stop the event dispatcher");
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_setup_service_core(struct test_app *app, unsigned int lcore_id)
+{
+	int rc;
+
+	rc = rte_service_lcore_add(lcore_id);
+	TEST_ASSERT_SUCCESS(rc, "Unable to make lcore %d an event dispatcher "
+			    "service core", lcore_id);
+
+	rc = rte_service_map_lcore_set(app->dispatcher_service_id, lcore_id, 1);
+	TEST_ASSERT_SUCCESS(rc, "Unable to map event dispatcher service");
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_setup_service_cores(struct test_app *app)
+{
+	int i;
+	int lcore_id = -1;
+
+	for (i = 0; i < NUM_SERVICE_CORES; i++) {
+		lcore_id = rte_get_next_lcore(lcore_id, 1, 0);
+
+		TEST_ASSERT(lcore_id != RTE_MAX_LCORE,
+			    "Too few lcores. Needs at least %d worker lcores",
+			    NUM_SERVICE_CORES);
+
+		app->service_lcores[i] = lcore_id;
+	}
+
+	for (i = 0; i < NUM_SERVICE_CORES; i++) {
+		int rc;
+
+		rc = test_app_setup_service_core(app, app->service_lcores[i]);
+
+		RETURN_ON_ERROR(rc);
+	}
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_teardown_service_core(struct test_app *app, unsigned int lcore_id)
+{
+	int rc;
+
+	rc = rte_service_map_lcore_set(app->dispatcher_service_id, lcore_id, 0);
+	TEST_ASSERT_SUCCESS(rc, "Unable to unmap event dispatcher service");
+
+	rc = rte_service_lcore_del(lcore_id);
+	TEST_ASSERT_SUCCESS(rc, "Unable change role of service lcore %d",
+			    lcore_id);
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_teardown_service_cores(struct test_app *app)
+{
+	int i;
+
+	for (i = 0; i < NUM_SERVICE_CORES; i++) {
+		unsigned int lcore_id = app->service_lcores[i];
+		int rc;
+
+		rc = test_app_teardown_service_core(app, lcore_id);
+
+		RETURN_ON_ERROR(rc);
+	}
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_start_service_cores(struct test_app *app)
+{
+	int i;
+
+	for (i = 0; i < NUM_SERVICE_CORES; i++) {
+		unsigned int lcore_id = app->service_lcores[i];
+		int rc;
+
+		rc = rte_service_lcore_start(lcore_id);
+		TEST_ASSERT_SUCCESS(rc, "Unable to start service lcore %d",
+				    lcore_id);
+
+		RETURN_ON_ERROR(rc);
+	}
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_stop_service_cores(struct test_app *app)
+{
+	int i;
+
+	for (i = 0; i < NUM_SERVICE_CORES; i++) {
+		unsigned int lcore_id = app->service_lcores[i];
+		int rc;
+
+		rc = rte_service_lcore_stop(lcore_id);
+		TEST_ASSERT_SUCCESS(rc, "Unable to stop service lcore %d",
+				    lcore_id);
+
+		RETURN_ON_ERROR(rc);
+	}
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_app_start(struct test_app *app)
+{
+	int rc;
+
+	rc = test_app_start_event_dev(app);
+	RETURN_ON_ERROR(rc);
+
+	rc = test_app_start_service_cores(app);
+	RETURN_ON_ERROR(rc);
+
+	rc = test_app_start_dispatcher(app);
+
+	app->running = true;
+
+	return rc;
+}
+
+static int
+test_app_stop(struct test_app *app)
+{
+	int rc;
+
+	rc = test_app_stop_dispatcher(app);
+	RETURN_ON_ERROR(rc);
+
+	test_app_stop_service_cores(app);
+	RETURN_ON_ERROR(rc);
+
+	test_app_stop_event_dev(app);
+	RETURN_ON_ERROR(rc);
+
+	app->running = false;
+
+	return TEST_SUCCESS;
+}
+
+struct test_app *test_app;
+
+static int
+test_setup(void)
+{
+	int rc;
+
+	test_app = test_app_create();
+	TEST_ASSERT(test_app != NULL, "Unable to allocate memory");
+
+	rc = test_app_setup_event_dev(test_app);
+	RETURN_ON_ERROR(rc);
+
+	rc = test_app_create_dispatcher(test_app);
+
+	rc = test_app_setup_service_cores(test_app);
+	RETURN_ON_ERROR(rc);
+
+	rc = test_app_register_callbacks(test_app);
+	RETURN_ON_ERROR(rc);
+
+	rc = test_app_bind_ports(test_app);
+
+	return rc;
+}
+
+static void test_teardown(void)
+{
+	if (test_app->running)
+		test_app_stop(test_app);
+
+	test_app_teardown_service_cores(test_app);
+
+	test_app_unregister_callbacks(test_app);
+
+	test_app_unbind_ports(test_app);
+
+	test_app_free_dispatcher(test_app);
+
+	test_app_teardown_event_dev(test_app);
+
+	test_app_free(test_app);
+
+	test_app = NULL;
+}
+
+static int
+test_app_get_completed_events(struct test_app *app)
+{
+	return atomic_load_explicit(&app->completed_events,
+				    memory_order_relaxed);
+}
+
+static int
+test_app_get_errors(struct test_app *app)
+{
+	return atomic_load_explicit(&app->errors, memory_order_relaxed);
+}
+
+static int
+test_basic(void)
+{
+	int rc;
+	int i;
+
+	rc = test_app_start(test_app);
+	RETURN_ON_ERROR(rc);
+
+	uint64_t sns[NUM_FLOWS] = { 0 };
+
+	for (i = 0; i < NUM_EVENTS;) {
+		struct rte_event events[ENQUEUE_BURST_SIZE];
+		int left;
+		int batch_size;
+		int j;
+		uint16_t n = 0;
+
+		batch_size = 1 + rte_rand_max(ENQUEUE_BURST_SIZE);
+		left = NUM_EVENTS - i;
+
+		batch_size = RTE_MIN(left, batch_size);
+
+		for (j = 0; j < batch_size; j++) {
+			struct rte_event *event = &events[j];
+			uint64_t sn;
+			uint32_t flow_id;
+
+			flow_id = rte_rand_max(NUM_FLOWS);
+
+			sn = sns[flow_id]++;
+
+			*event = (struct rte_event) {
+				.queue_id = 0,
+				.flow_id = flow_id,
+				.sched_type = RTE_SCHED_TYPE_ATOMIC,
+				.op = RTE_EVENT_OP_NEW,
+				.priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
+				.u64 = sn
+			};
+		}
+
+		while (n < batch_size)
+			n += rte_event_enqueue_new_burst(test_app->event_dev_id,
+							 DRIVER_PORT_ID,
+							 events + n,
+							 batch_size - n);
+
+		i += batch_size;
+	}
+
+	while (test_app_get_completed_events(test_app) != NUM_EVENTS)
+		rte_event_maintain(test_app->event_dev_id, DRIVER_PORT_ID, 0);
+
+	rc = test_app_get_errors(test_app);
+	TEST_ASSERT(rc == 0, "%d errors occurred", rc);
+
+	rc = test_app_stop(test_app);
+	RETURN_ON_ERROR(rc);
+
+	struct rte_event_dispatcher_stats stats;
+	rc = rte_event_dispatcher_stats_get(test_app->dispatcher_id,
+					    &stats);
+
+	TEST_ASSERT_EQUAL(stats.ev_drop_count, 0, "Drop count is not zero");
+	TEST_ASSERT_EQUAL(stats.ev_dispatch_count, NUM_EVENTS * NUM_QUEUES,
+			  "Invalid dispatch count");
+	TEST_ASSERT(stats.poll_count > 0, "Poll count is zero");
+
+	TEST_ASSERT_EQUAL(test_app->never_process_count, 0, "Never-match "
+			  "handler's process function has been called");
+
+	/*
+	 * The event dispatcher should call often-matching match functions
+	 * more often, and thus this never-matching match function should
+	 * be called relatively infrequently.
+	 */
+	TEST_ASSERT(test_app->never_match_count <
+		    (stats.ev_dispatch_count / 4),
+		    "Never-matching match function called suspiciously often");
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_drop(void)
+{
+	int rc;
+	uint8_t unhandled_queue = 1;
+	struct rte_event_dispatcher_stats stats;
+
+	rc = test_app_start(test_app);
+	RETURN_ON_ERROR(rc);
+
+	rc = test_app_unregister_callback(test_app, unhandled_queue);
+	RETURN_ON_ERROR(rc);
+
+	struct rte_event event = {
+	    .queue_id = unhandled_queue,
+	    .flow_id = 0,
+	    .sched_type = RTE_SCHED_TYPE_ATOMIC,
+	    .op = RTE_EVENT_OP_NEW,
+	    .priority = RTE_EVENT_DEV_PRIORITY_NORMAL,
+	    .u64 = 0
+	};
+
+	do {
+		rc = rte_event_enqueue_burst(test_app->event_dev_id,
+					     DRIVER_PORT_ID, &event, 1);
+	} while (rc == 0);
+
+	do {
+		rc = rte_event_dispatcher_stats_get(test_app->dispatcher_id,
+						    &stats);
+		RETURN_ON_ERROR(rc);
+
+		rte_event_maintain(test_app->event_dev_id, DRIVER_PORT_ID, 0);
+	} while (stats.ev_drop_count == 0 && stats.ev_dispatch_count == 0);
+
+	rc = test_app_stop(test_app);
+	RETURN_ON_ERROR(rc);
+
+	TEST_ASSERT_EQUAL(stats.ev_drop_count, 1, "Drop count is not one");
+	TEST_ASSERT_EQUAL(stats.ev_dispatch_count, 0,
+			  "Dispatch count is not zero");
+	TEST_ASSERT(stats.poll_count > 0, "Poll count is zero");
+
+	return TEST_SUCCESS;
+}
+
+static struct unit_test_suite test_suite = {
+	.suite_name = "Event dispatcher test suite",
+	.unit_test_cases = {
+		TEST_CASE_ST(test_setup, test_teardown, test_basic),
+		TEST_CASE_ST(test_setup, test_teardown, test_drop),
+		TEST_CASES_END()
+	}
+};
+
+static int
+test_event_dispatcher(void)
+{
+	return unit_test_suite_runner(&test_suite);
+}
+
+REGISTER_TEST_COMMAND(event_dispatcher_autotest, test_event_dispatcher);
-- 
2.34.1