[dpdk-dev,3/5] eventdev: add ring structure for events

Message ID 20170607133620.275801-4-bruce.richardson@intel.com (mailing list archive)
State Superseded, archived
Headers

Checks

Context Check Description
ci/checkpatch warning coding style issues
ci/Intel-compilation success Compilation OK

Commit Message

Bruce Richardson June 7, 2017, 1:36 p.m. UTC
  Add in a new rte_event_ring structure type and functions to allow events to
be passed core to core. This is needed because the standard rte_ring type
only works on pointers, while for events, we want to copy the entire, 16B
events themselves - not just pointers to them. The code makes extensive use
of the functions already defined in rte_ring.h

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 lib/Makefile                                 |   2 +-
 lib/librte_eventdev/Makefile                 |   2 +
 lib/librte_eventdev/rte_event_ring.c         | 207 ++++++++++++++++++
 lib/librte_eventdev/rte_event_ring.h         | 312 +++++++++++++++++++++++++++
 lib/librte_eventdev/rte_eventdev_version.map |   9 +
 5 files changed, 531 insertions(+), 1 deletion(-)
 create mode 100644 lib/librte_eventdev/rte_event_ring.c
 create mode 100644 lib/librte_eventdev/rte_event_ring.h
  

Comments

Jerin Jacob June 12, 2017, 5:15 a.m. UTC | #1
-----Original Message-----
> Date: Wed, 7 Jun 2017 14:36:18 +0100
> From: Bruce Richardson <bruce.richardson@intel.com>
> To: dev@dpdk.org
> CC: olivier.matz@6wind.com, jerin.jacob@caviumnetworks.com, Bruce
>  Richardson <bruce.richardson@intel.com>
> Subject: [PATCH 3/5] eventdev: add ring structure for events
> X-Mailer: git-send-email 2.9.4
> 
> Add in a new rte_event_ring structure type and functions to allow events to
> be passed core to core. This is needed because the standard rte_ring type
> only works on pointers, while for events, we want to copy the entire, 16B
> events themselves - not just pointers to them. The code makes extensive use
> of the functions already defined in rte_ring.h
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>


Thomas,

Should this series applied through dpdk/master or dpdk-next-eventdev/master?

Bruce,
__rte_always_inline macro is now part of master. Good to replace with force_inline.
  
Bruce Richardson June 12, 2017, 8:53 a.m. UTC | #2
On Mon, Jun 12, 2017 at 10:45:47AM +0530, Jerin Jacob wrote:
> -----Original Message-----
> > Date: Wed, 7 Jun 2017 14:36:18 +0100
> > From: Bruce Richardson <bruce.richardson@intel.com>
> > To: dev@dpdk.org
> > CC: olivier.matz@6wind.com, jerin.jacob@caviumnetworks.com, Bruce
> >  Richardson <bruce.richardson@intel.com>
> > Subject: [PATCH 3/5] eventdev: add ring structure for events
> > X-Mailer: git-send-email 2.9.4
> > 
> > Add in a new rte_event_ring structure type and functions to allow events to
> > be passed core to core. This is needed because the standard rte_ring type
> > only works on pointers, while for events, we want to copy the entire, 16B
> > events themselves - not just pointers to them. The code makes extensive use
> > of the functions already defined in rte_ring.h
> > 
> > Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> 
> 
> Thomas,
> 
> Should this series applied through dpdk/master or dpdk-next-eventdev/master?
> 
> Bruce,
> __rte_always_inline macro is now part of master. Good to replace with force_inline.

Yes, good point. Thanks.

/Bruce
  
Bruce Richardson June 30, 2017, 1:24 p.m. UTC | #3
On Mon, Jun 12, 2017 at 10:45:47AM +0530, Jerin Jacob wrote:
> -----Original Message-----
> > Date: Wed, 7 Jun 2017 14:36:18 +0100
> > From: Bruce Richardson <bruce.richardson@intel.com>
> > To: dev@dpdk.org
> > CC: olivier.matz@6wind.com, jerin.jacob@caviumnetworks.com, Bruce
> >  Richardson <bruce.richardson@intel.com>
> > Subject: [PATCH 3/5] eventdev: add ring structure for events
> > X-Mailer: git-send-email 2.9.4
> > 
> > Add in a new rte_event_ring structure type and functions to allow events to
> > be passed core to core. This is needed because the standard rte_ring type
> > only works on pointers, while for events, we want to copy the entire, 16B
> > events themselves - not just pointers to them. The code makes extensive use
> > of the functions already defined in rte_ring.h
> > 
> > Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> 
> 
> Thomas,
> 
> Should this series applied through dpdk/master or dpdk-next-eventdev/master?

I'll leave that up to yourself and Thomas to sort out. My 2c. is that it
probably belongs better in the eventdev tree, especially since the rings
code doesn't see many, if any, changes on mainline anyway to conflict
with this.
I'm going to do up a V2 based on all the feedback this afternoon.

> 
> Bruce,
> __rte_always_inline macro is now part of master. Good to replace with force_inline.
  

Patch

diff --git a/lib/Makefile b/lib/Makefile
index 07e1fd0..aef584e 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -52,7 +52,7 @@  DIRS-$(CONFIG_RTE_LIBRTE_CRYPTODEV) += librte_cryptodev
 DEPDIRS-librte_cryptodev := librte_eal librte_mempool librte_ring librte_mbuf
 DEPDIRS-librte_cryptodev += librte_kvargs
 DIRS-$(CONFIG_RTE_LIBRTE_EVENTDEV) += librte_eventdev
-DEPDIRS-librte_eventdev := librte_eal
+DEPDIRS-librte_eventdev := librte_eal librte_ring
 DIRS-$(CONFIG_RTE_LIBRTE_VHOST) += librte_vhost
 DEPDIRS-librte_vhost := librte_eal librte_mempool librte_mbuf librte_ether
 DIRS-$(CONFIG_RTE_LIBRTE_HASH) += librte_hash
diff --git a/lib/librte_eventdev/Makefile b/lib/librte_eventdev/Makefile
index e06346a..0313277 100644
--- a/lib/librte_eventdev/Makefile
+++ b/lib/librte_eventdev/Makefile
@@ -42,10 +42,12 @@  CFLAGS += $(WERROR_FLAGS)
 
 # library source files
 SRCS-y += rte_eventdev.c
+SRCS-y += rte_event_ring.c
 
 # export include files
 SYMLINK-y-include += rte_eventdev.h
 SYMLINK-y-include += rte_eventdev_pmd.h
+SYMLINK-y-include += rte_event_ring.h
 
 # versioning export map
 EXPORT_MAP := rte_eventdev_version.map
diff --git a/lib/librte_eventdev/rte_event_ring.c b/lib/librte_eventdev/rte_event_ring.c
new file mode 100644
index 0000000..b14c212
--- /dev/null
+++ b/lib/librte_eventdev/rte_event_ring.c
@@ -0,0 +1,207 @@ 
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2017 Intel Corporation. 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 <sys/queue.h>
+#include <string.h>
+
+#include <rte_tailq.h>
+#include <rte_memzone.h>
+#include <rte_rwlock.h>
+#include <rte_eal_memconfig.h>
+#include "rte_event_ring.h"
+
+TAILQ_HEAD(rte_event_ring_list, rte_tailq_entry);
+
+static struct rte_tailq_elem rte_event_ring_tailq = {
+	.name = RTE_TAILQ_EVENT_RING_NAME,
+};
+EAL_REGISTER_TAILQ(rte_event_ring_tailq)
+
+int
+rte_event_ring_init(struct rte_event_ring *r, const char *name,
+	unsigned int count, unsigned int flags)
+{
+	/* compilation-time checks */
+	RTE_BUILD_BUG_ON((sizeof(struct rte_event_ring) &
+			  RTE_CACHE_LINE_MASK) != 0);
+
+	/* init the ring structure */
+	return rte_ring_init(&r->r, name, count, flags);
+}
+
+/* create the ring */
+struct rte_event_ring *
+rte_event_ring_create(const char *name, unsigned int count, int socket_id,
+		unsigned int flags)
+{
+	char mz_name[RTE_MEMZONE_NAMESIZE];
+	struct rte_event_ring *r;
+	struct rte_tailq_entry *te;
+	const struct rte_memzone *mz;
+	ssize_t ring_size;
+	int mz_flags = 0;
+	struct rte_event_ring_list *ring_list = NULL;
+	const unsigned int requested_count = count;
+	int ret;
+
+	ring_list = RTE_TAILQ_CAST(rte_event_ring_tailq.head,
+		rte_event_ring_list);
+
+	/* for an exact size ring, round up from count to a power of two */
+	if (flags & RING_F_EXACT_SZ)
+		count = rte_align32pow2(count + 1);
+	else if (!rte_is_power_of_2(count)) {
+		rte_errno = EINVAL;
+		return NULL;
+	}
+
+	ring_size = sizeof(*r) + (count * sizeof(struct rte_event));
+
+	ret = snprintf(mz_name, sizeof(mz_name), "%s%s",
+		RTE_RING_MZ_PREFIX, name);
+	if (ret < 0 || ret >= (int)sizeof(mz_name)) {
+		rte_errno = ENAMETOOLONG;
+		return NULL;
+	}
+
+	te = rte_zmalloc("RING_TAILQ_ENTRY", sizeof(*te), 0);
+	if (te == NULL) {
+		RTE_LOG(ERR, RING, "Cannot reserve memory for tailq\n");
+		rte_errno = ENOMEM;
+		return NULL;
+	}
+
+	rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
+
+	/*
+	 * reserve a memory zone for this ring. If we can't get rte_config or
+	 * we are secondary process, the memzone_reserve function will set
+	 * rte_errno for us appropriately - hence no check in this this function
+	 */
+	mz = rte_memzone_reserve(mz_name, ring_size, socket_id, mz_flags);
+	if (mz != NULL) {
+		r = mz->addr;
+		/*
+		 * no need to check return value here, we already checked the
+		 * arguments above
+		 */
+		rte_event_ring_init(r, name, requested_count, flags);
+
+		te->data = (void *) r;
+		r->r.memzone = mz;
+
+		TAILQ_INSERT_TAIL(ring_list, te, next);
+	} else {
+		r = NULL;
+		RTE_LOG(ERR, RING, "Cannot reserve memory\n");
+		rte_free(te);
+	}
+	rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
+
+	return r;
+}
+
+
+struct rte_event_ring *
+rte_event_ring_lookup(const char *name)
+{
+	struct rte_tailq_entry *te;
+	struct rte_event_ring *r = NULL;
+	struct rte_event_ring_list *ring_list;
+
+	ring_list = RTE_TAILQ_CAST(rte_event_ring_tailq.head,
+			rte_event_ring_list);
+
+	rte_rwlock_read_lock(RTE_EAL_TAILQ_RWLOCK);
+
+	TAILQ_FOREACH(te, ring_list, next) {
+		r = (struct rte_event_ring *) te->data;
+		if (strncmp(name, r->r.name, RTE_RING_NAMESIZE) == 0)
+			break;
+	}
+
+	rte_rwlock_read_unlock(RTE_EAL_TAILQ_RWLOCK);
+
+	if (te == NULL) {
+		rte_errno = ENOENT;
+		return NULL;
+	}
+
+	return r;
+}
+
+/* free the ring */
+void
+rte_event_ring_free(struct rte_event_ring *r)
+{
+	struct rte_event_ring_list *ring_list = NULL;
+	struct rte_tailq_entry *te;
+
+	if (r == NULL)
+		return;
+
+	/*
+	 * Ring was not created with rte_event_ring_create,
+	 * therefore, there is no memzone to free.
+	 */
+	if (r->r.memzone == NULL) {
+		RTE_LOG(ERR, RING,
+			"Cannot free ring (not created with rte_event_ring_create()");
+		return;
+	}
+
+	if (rte_memzone_free(r->r.memzone) != 0) {
+		RTE_LOG(ERR, RING, "Cannot free memory\n");
+		return;
+	}
+
+	ring_list = RTE_TAILQ_CAST(rte_event_ring_tailq.head,
+			rte_event_ring_list);
+	rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
+
+	/* find out tailq entry */
+	TAILQ_FOREACH(te, ring_list, next) {
+		if (te->data == (void *) r)
+			break;
+	}
+
+	if (te == NULL) {
+		rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
+		return;
+	}
+
+	TAILQ_REMOVE(ring_list, te, next);
+
+	rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
+
+	rte_free(te);
+}
diff --git a/lib/librte_eventdev/rte_event_ring.h b/lib/librte_eventdev/rte_event_ring.h
new file mode 100644
index 0000000..f7eae58
--- /dev/null
+++ b/lib/librte_eventdev/rte_event_ring.h
@@ -0,0 +1,312 @@ 
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2016-2017 Intel Corporation. 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.
+ */
+
+/**
+ * @file
+ * RTE Event Ring
+ *
+ * This provides a ring implementation for passing rte_event structures
+ * from one core to another.
+ */
+
+#ifndef _RTE_EVENT_RING_
+#define _RTE_EVENT_RING_
+
+#include <stdint.h>
+
+#include <rte_common.h>
+#include <rte_memory.h>
+#include <rte_malloc.h>
+#include <rte_ring.h>
+#include "rte_eventdev.h"
+
+#define RTE_TAILQ_EVENT_RING_NAME "RTE_EVENT_RING"
+
+#ifndef force_inline
+#define force_inline inline __attribute__((always_inline))
+#endif
+
+/**
+ * Generic ring structure for passing rte_event objects from core to core.
+ *
+ * Based on the primitives given in the rte_ring library. Designed to be
+ * used inside software eventdev implementations and by applications
+ * directly as needed.
+ */
+struct rte_event_ring {
+	struct rte_ring r;
+};
+
+/**
+ * Returns the number of events in the ring
+ *
+ * @param r
+ *   pointer to the event ring
+ * @return
+ *   the number of events in the ring
+ */
+static force_inline unsigned int
+rte_event_ring_count(const struct rte_event_ring *r)
+{
+	return rte_ring_count(&r->r);
+}
+
+/**
+ * Returns the amount of free space in the ring
+ *
+ * @param r
+ *   pointer to the event ring
+ * @return
+ *   the number of free slots in the ring, i.e. the number of events that
+ *   can be successfully enqueued before dequeue must be called
+ */
+static force_inline unsigned int
+rte_event_ring_free_count(const struct rte_event_ring *r)
+{
+	return rte_ring_free_count(&r->r);
+}
+
+/**
+ * Enqueue a set of events onto a ring
+ *
+ * Note: this API enqueues by copying the events themselves onto the ring,
+ * rather than just placing a pointer to each event onto the ring. This
+ * means that statically-allocated events can safely be enqueued by this
+ * API.
+ *
+ * @param r
+ *   pointer to the event ring
+ * @param events
+ *   pointer to an array of struct rte_event objects
+ * @param n
+ *   number of events in the array to enqueue
+ * @param free_space
+ *   if non-null, is updated to indicate the amount of free space in the
+ *   ring once the enqueue has completed.
+ * @return
+ *   the number of elements, n', enqueued to the ring, 0 <= n' <= n
+ */
+static force_inline unsigned int
+rte_event_ring_enqueue_burst(struct rte_event_ring *r,
+		const struct rte_event *events,
+		unsigned int n, uint16_t *free_space)
+{
+	uint32_t prod_head, prod_next;
+	uint32_t free_entries;
+
+	n = __rte_ring_move_prod_head(&r->r, r->r.prod.single, n,
+			RTE_RING_QUEUE_VARIABLE,
+			&prod_head, &prod_next, &free_entries);
+	if (n == 0)
+		goto end;
+
+	ENQUEUE_PTRS(&r->r, &r[1], prod_head, events, n, struct rte_event);
+	rte_smp_wmb();
+
+	update_tail(&r->r.prod, prod_head, prod_next, 1);
+end:
+	if (free_space != NULL)
+		*free_space = free_entries - n;
+	return n;
+}
+
+/**
+ * Dequeue a set of events from a ring
+ *
+ * Note: this API does not work with pointers to events, rather it copies
+ * the events themselves to the destination ``events`` buffer.
+ *
+ * @param r
+ *   pointer to the event ring
+ * @param events
+ *   pointer to an array to hold the struct rte_event objects
+ * @param n
+ *   number of events that can be held in the ``events`` array
+ * @param available
+ *   if non-null, is updated to indicate the number of events remaining in
+ *   the ring once the dequeue has completed
+ * @return
+ *   the number of elements, n', dequeued from the ring, 0 <= n' <= n
+ */
+static force_inline unsigned int
+rte_event_ring_dequeue_burst(struct rte_event_ring *r,
+		struct rte_event *events,
+		unsigned int n, uint16_t *available)
+{
+	uint32_t cons_head, cons_next;
+	uint32_t entries;
+
+	n = __rte_ring_move_cons_head(&r->r, r->r.cons.single, n,
+			RTE_RING_QUEUE_VARIABLE,
+			&cons_head, &cons_next, &entries);
+	if (n == 0)
+		goto end;
+
+	DEQUEUE_PTRS(&r->r, &r[1], cons_head, events, n, struct rte_event);
+	rte_smp_rmb();
+
+	update_tail(&r->r.cons, cons_head, cons_next, 1);
+
+end:
+	if (available != NULL)
+		*available = entries - n;
+	return n;
+}
+
+/*
+ * Initializes an already-allocated ring structure
+ *
+ * @param r
+ *   pointer to the ring memory to be initialized
+ * @param name
+ *   name to be given to the ring
+ * @param count
+ *   the number of elements to be stored in the ring. If the flag
+ *   ``RING_F_EXACT_SZ`` is not set, this must be a power of 2, and the actual
+ *   usable space in the ring will be ``count - 1`` entries. If the flag
+ *   ``RING_F_EXACT_SZ`` is set, the this can be any value up to the ring size
+ *   limit - 1, and the usable space will be exactly that requested.
+ * @param flags
+ *   An OR of the following:
+ *    - RING_F_SP_ENQ: If this flag is set, the default behavior when
+ *      using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ *      is "single-producer". Otherwise, it is "multi-producers".
+ *    - RING_F_SC_DEQ: If this flag is set, the default behavior when
+ *      using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ *      is "single-consumer". Otherwise, it is "multi-consumers".
+ *    - RING_F_EXACT_SZ: If this flag is set, the ``count`` parameter is to
+ *      be taken as the exact usable size of the ring, and as such does not
+ *      need to be a power of 2. The underlying ring memory should be a
+ *      power-of-2 size greater than the count value.
+ * @return
+ *   0 on success, or a negative value on error.
+ */
+int
+rte_event_ring_init(struct rte_event_ring *r, const char *name,
+	unsigned int count, unsigned int flags);
+
+/*
+ * Create an event ring structure
+ *
+ * This function allocates memory and initializes an event ring inside that
+ * memory.
+ *
+ * @param name
+ *   name to be given to the ring
+ * @param count
+ *   the number of elements to be stored in the ring. If the flag
+ *   ``RING_F_EXACT_SZ`` is not set, this must be a power of 2, and the actual
+ *   usable space in the ring will be ``count - 1`` entries. If the flag
+ *   ``RING_F_EXACT_SZ`` is set, the this can be any value up to the ring size
+ *   limit - 1, and the usable space will be exactly that requested.
+ * @param socket_id
+ *   The *socket_id* argument is the socket identifier in case of
+ *   NUMA. The value can be *SOCKET_ID_ANY* if there is no NUMA
+ *   constraint for the reserved zone.
+ * @param flags
+ *   An OR of the following:
+ *    - RING_F_SP_ENQ: If this flag is set, the default behavior when
+ *      using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ *      is "single-producer". Otherwise, it is "multi-producers".
+ *    - RING_F_SC_DEQ: If this flag is set, the default behavior when
+ *      using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ *      is "single-consumer". Otherwise, it is "multi-consumers".
+ *    - RING_F_EXACT_SZ: If this flag is set, the ``count`` parameter is to
+ *      be taken as the exact usable size of the ring, and as such does not
+ *      need to be a power of 2. The underlying ring memory should be a
+ *      power-of-2 size greater than the count value.
+ * @return
+ *   On success, the pointer to the new allocated ring. NULL on error with
+ *    rte_errno set appropriately. Possible errno values include:
+ *    - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
+ *    - E_RTE_SECONDARY - function was called from a secondary process instance
+ *    - EINVAL - count provided is not a power of 2
+ *    - ENOSPC - the maximum number of memzones has already been allocated
+ *    - EEXIST - a memzone with the same name already exists
+ *    - ENOMEM - no appropriate memory area found in which to create memzone
+ */
+struct rte_event_ring *
+rte_event_ring_create(const char *name, unsigned int count, int socket_id,
+		unsigned int flags);
+
+/**
+ * Search for an event ring based on its name
+ *
+ * @param name
+ *   The name of the ring.
+ * @return
+ *   The pointer to the ring matching the name, or NULL if not found,
+ *   with rte_errno set appropriately. Possible rte_errno values include:
+ *    - ENOENT - required entry not available to return.
+ */
+struct rte_event_ring *
+rte_event_ring_lookup(const char *name);
+
+/**
+ * De-allocate all memory used by the ring.
+ *
+ * @param r
+ *   Ring to free
+ */
+void
+rte_event_ring_free(struct rte_event_ring *r);
+
+/**
+ * Return the size of the event ring.
+ *
+ * @param r
+ *   A pointer to the ring structure.
+ * @return
+ *   The size of the data store used by the ring.
+ *   NOTE: this is not the same as the usable space in the ring. To query that
+ *   use ``rte_ring_get_capacity()``.
+ */
+static inline unsigned int
+rte_event_ring_get_size(const struct rte_event_ring *r)
+{
+	return rte_ring_get_size(&r->r);
+}
+
+/**
+ * Return the number of elements which can be stored in the event ring.
+ *
+ * @param r
+ *   A pointer to the ring structure.
+ * @return
+ *   The usable size of the ring.
+ */
+static inline unsigned int
+rte_event_ring_get_capacity(const struct rte_event_ring *r)
+{
+	return rte_ring_get_capacity(&r->r);
+}
+#endif
diff --git a/lib/librte_eventdev/rte_eventdev_version.map b/lib/librte_eventdev/rte_eventdev_version.map
index 1fa6b33..4c48e5f 100644
--- a/lib/librte_eventdev/rte_eventdev_version.map
+++ b/lib/librte_eventdev/rte_eventdev_version.map
@@ -42,3 +42,12 @@  DPDK_17.05 {
 
 	local: *;
 };
+
+DPDK_17.08 {
+	global:
+
+	rte_event_ring_create;
+	rte_event_ring_free;
+	rte_event_ring_init;
+	rte_event_ring_lookup;
+} DPDK_17.05;