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authorSergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>2015-02-18 14:58:13 +0000
committerThomas Monjalon <thomas.monjalon@6wind.com>2015-02-18 16:52:05 +0100
commitb70b56032bff9d647c3bedcad7bdba9ca30bb85a (patch)
treeddece0ea4f08d6c5666e4d03e935e5f359459400 /lib/librte_reorder
parentc07691ae10894bb6bf284fed75829b95844eacdb (diff)
downloaddpdk-b70b56032bff9d647c3bedcad7bdba9ca30bb85a.zip
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reorder: new library
This library provides reordering capability for out of order mbufs based on a sequence number in the mbuf structure. Signed-off-by: Reshma Pattan <reshma.pattan@intel.com> Signed-off-by: Richardson Bruce <bruce.richardson@intel.com> Signed-off-by: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Declan Doherty <declan.doherty@intel.com>
Diffstat (limited to 'lib/librte_reorder')
-rw-r--r--lib/librte_reorder/Makefile54
-rw-r--r--lib/librte_reorder/rte_reorder.c416
-rw-r--r--lib/librte_reorder/rte_reorder.h181
-rw-r--r--lib/librte_reorder/rte_reorder_version.map13
4 files changed, 664 insertions, 0 deletions
diff --git a/lib/librte_reorder/Makefile b/lib/librte_reorder/Makefile
new file mode 100644
index 0000000..0c01de1
--- /dev/null
+++ b/lib/librte_reorder/Makefile
@@ -0,0 +1,54 @@
+# 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_SDK)/mk/rte.vars.mk
+
+# library name
+LIB = librte_reorder.a
+
+CFLAGS += -O3
+CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR)
+
+EXPORT_MAP := rte_reorder_version.map
+
+LIBABIVER := 1
+
+# all source are stored in SRCS-y
+SRCS-$(CONFIG_RTE_LIBRTE_REORDER) := rte_reorder.c
+
+# install this header file
+SYMLINK-$(CONFIG_RTE_LIBRTE_REORDER)-include := rte_reorder.h
+
+# this lib depends upon:
+DEPDIRS-$(CONFIG_RTE_LIBRTE_REORDER) += lib/librte_mbuf
+DEPDIRS-$(CONFIG_RTE_LIBRTE_REORDER) += lib/librte_eal
+
+include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/lib/librte_reorder/rte_reorder.c b/lib/librte_reorder/rte_reorder.c
new file mode 100644
index 0000000..42d2a47
--- /dev/null
+++ b/lib/librte_reorder/rte_reorder.c
@@ -0,0 +1,416 @@
+/*-
+ * 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 <inttypes.h>
+#include <string.h>
+
+#include <rte_log.h>
+#include <rte_mbuf.h>
+#include <rte_memzone.h>
+#include <rte_eal_memconfig.h>
+#include <rte_errno.h>
+#include <rte_tailq.h>
+#include <rte_malloc.h>
+
+#include "rte_reorder.h"
+
+TAILQ_HEAD(rte_reorder_list, rte_tailq_entry);
+
+#define NO_FLAGS 0
+#define RTE_REORDER_PREFIX "RO_"
+#define RTE_REORDER_NAMESIZE 32
+
+/* Macros for printing using RTE_LOG */
+#define RTE_LOGTYPE_REORDER RTE_LOGTYPE_USER1
+
+/* A generic circular buffer */
+struct cir_buffer {
+ unsigned int size; /**< Number of entries that can be stored */
+ unsigned int mask; /**< [buffer_size - 1]: used for wrap-around */
+ unsigned int head; /**< insertion point in buffer */
+ unsigned int tail; /**< extraction point in buffer */
+ struct rte_mbuf **entries;
+} __rte_cache_aligned;
+
+/* The reorder buffer data structure itself */
+struct rte_reorder_buffer {
+ char name[RTE_REORDER_NAMESIZE];
+ uint32_t min_seqn; /**< Lowest seq. number that can be in the buffer */
+ unsigned int memsize; /**< memory area size of reorder buffer */
+ struct cir_buffer ready_buf; /**< temp buffer for dequeued entries */
+ struct cir_buffer order_buf; /**< buffer used to reorder entries */
+} __rte_cache_aligned;
+
+static void
+rte_reorder_free_mbufs(struct rte_reorder_buffer *b);
+
+struct rte_reorder_buffer *
+rte_reorder_init(struct rte_reorder_buffer *b, unsigned int bufsize,
+ const char *name, unsigned int size)
+{
+ const unsigned int min_bufsize = sizeof(*b) +
+ (2 * size * sizeof(struct rte_mbuf *));
+
+ if (b == NULL) {
+ RTE_LOG(ERR, REORDER, "Invalid reorder buffer parameter:"
+ " NULL\n");
+ rte_errno = EINVAL;
+ return NULL;
+ }
+ if (!rte_is_power_of_2(size)) {
+ RTE_LOG(ERR, REORDER, "Invalid reorder buffer size"
+ " - Not a power of 2\n");
+ rte_errno = EINVAL;
+ return NULL;
+ }
+ if (name == NULL) {
+ RTE_LOG(ERR, REORDER, "Invalid reorder buffer name ptr:"
+ " NULL\n");
+ rte_errno = EINVAL;
+ return NULL;
+ }
+ if (bufsize < min_bufsize) {
+ RTE_LOG(ERR, REORDER, "Invalid reorder buffer memory size: %u, "
+ "minimum required: %u\n", bufsize, min_bufsize);
+ rte_errno = EINVAL;
+ return NULL;
+ }
+
+ memset(b, 0, bufsize);
+ snprintf(b->name, sizeof(b->name), "%s", name);
+ b->memsize = bufsize;
+ b->order_buf.size = b->ready_buf.size = size;
+ b->order_buf.mask = b->ready_buf.mask = size - 1;
+ b->ready_buf.entries = (void *)&b[1];
+ b->order_buf.entries = RTE_PTR_ADD(&b[1],
+ size * sizeof(b->ready_buf.entries[0]));
+
+ return b;
+}
+
+struct rte_reorder_buffer*
+rte_reorder_create(const char *name, unsigned socket_id, unsigned int size)
+{
+ struct rte_reorder_buffer *b = NULL;
+ struct rte_tailq_entry *te;
+ struct rte_reorder_list *reorder_list;
+ const unsigned int bufsize = sizeof(struct rte_reorder_buffer) +
+ (2 * size * sizeof(struct rte_mbuf *));
+
+ /* check that we have an initialised tail queue */
+ reorder_list = RTE_TAILQ_LOOKUP_BY_IDX(RTE_TAILQ_REORDER, rte_reorder_list);
+ if (!reorder_list) {
+ rte_errno = E_RTE_NO_TAILQ;
+ return NULL;
+ }
+
+ /* Check user arguments. */
+ if (!rte_is_power_of_2(size)) {
+ RTE_LOG(ERR, REORDER, "Invalid reorder buffer size"
+ " - Not a power of 2\n");
+ rte_errno = EINVAL;
+ return NULL;
+ }
+ if (name == NULL) {
+ RTE_LOG(ERR, REORDER, "Invalid reorder buffer name ptr:"
+ " NULL\n");
+ rte_errno = EINVAL;
+ return NULL;
+ }
+
+ rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
+
+ /* guarantee there's no existing */
+ TAILQ_FOREACH(te, reorder_list, next) {
+ b = (struct rte_reorder_buffer *) te->data;
+ if (strncmp(name, b->name, RTE_REORDER_NAMESIZE) == 0)
+ break;
+ }
+ if (te != NULL)
+ goto exit;
+
+ /* allocate tailq entry */
+ te = rte_zmalloc("REORDER_TAILQ_ENTRY", sizeof(*te), 0);
+ if (te == NULL) {
+ RTE_LOG(ERR, REORDER, "Failed to allocate tailq entry\n");
+ rte_errno = ENOMEM;
+ b = NULL;
+ goto exit;
+ }
+
+ /* Allocate memory to store the reorder buffer structure. */
+ b = rte_zmalloc_socket("REORDER_BUFFER", bufsize, 0, socket_id);
+ if (b == NULL) {
+ RTE_LOG(ERR, REORDER, "Memzone allocation failed\n");
+ rte_errno = ENOMEM;
+ rte_free(te);
+ } else {
+ rte_reorder_init(b, bufsize, name, size);
+ te->data = (void *)b;
+ TAILQ_INSERT_TAIL(reorder_list, te, next);
+ }
+
+exit:
+ rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
+ return b;
+}
+
+void
+rte_reorder_reset(struct rte_reorder_buffer *b)
+{
+ char name[RTE_REORDER_NAMESIZE];
+
+ rte_reorder_free_mbufs(b);
+ snprintf(name, sizeof(name), "%s", b->name);
+ /* No error checking as current values should be valid */
+ rte_reorder_init(b, b->memsize, name, b->order_buf.size);
+}
+
+static void
+rte_reorder_free_mbufs(struct rte_reorder_buffer *b)
+{
+ unsigned i;
+
+ /* Free up the mbufs of order buffer & ready buffer */
+ for (i = 0; i < b->order_buf.size; i++) {
+ if (b->order_buf.entries[i])
+ rte_pktmbuf_free(b->order_buf.entries[i]);
+ if (b->ready_buf.entries[i])
+ rte_pktmbuf_free(b->ready_buf.entries[i]);
+ }
+}
+
+void
+rte_reorder_free(struct rte_reorder_buffer *b)
+{
+ struct rte_reorder_list *reorder_list;
+ struct rte_tailq_entry *te;
+
+ /* Check user arguments. */
+ if (b == NULL)
+ return;
+
+ /* check that we have an initialised tail queue */
+ reorder_list = RTE_TAILQ_LOOKUP_BY_IDX(RTE_TAILQ_REORDER, rte_reorder_list);
+ if (!reorder_list) {
+ rte_errno = E_RTE_NO_TAILQ;
+ return;
+ }
+
+ rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
+
+ /* find our tailq entry */
+ TAILQ_FOREACH(te, reorder_list, next) {
+ if (te->data == (void *) b)
+ break;
+ }
+ if (te == NULL) {
+ rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
+ return;
+ }
+
+ TAILQ_REMOVE(reorder_list, te, next);
+
+ rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
+
+ rte_reorder_free_mbufs(b);
+
+ rte_free(b);
+ rte_free(te);
+}
+
+struct rte_reorder_buffer *
+rte_reorder_find_existing(const char *name)
+{
+ struct rte_reorder_buffer *b = NULL;
+ struct rte_tailq_entry *te;
+ struct rte_reorder_list *reorder_list;
+
+ /* check that we have an initialised tail queue */
+ reorder_list = RTE_TAILQ_LOOKUP_BY_IDX(RTE_TAILQ_REORDER, rte_reorder_list);
+ if (!reorder_list) {
+ rte_errno = E_RTE_NO_TAILQ;
+ return NULL;
+ }
+
+ rte_rwlock_read_lock(RTE_EAL_TAILQ_RWLOCK);
+ TAILQ_FOREACH(te, reorder_list, next) {
+ b = (struct rte_reorder_buffer *) te->data;
+ if (strncmp(name, b->name, RTE_REORDER_NAMESIZE) == 0)
+ break;
+ }
+ rte_rwlock_read_unlock(RTE_EAL_TAILQ_RWLOCK);
+
+ if (te == NULL) {
+ rte_errno = ENOENT;
+ return NULL;
+ }
+
+ return b;
+}
+
+static unsigned
+rte_reorder_fill_overflow(struct rte_reorder_buffer *b, unsigned n)
+{
+ /*
+ * 1. Move all ready entries that fit to the ready_buf
+ * 2. check if we meet the minimum needed (n).
+ * 3. If not, then skip any gaps and keep moving.
+ * 4. If at any point the ready buffer is full, stop
+ * 5. Return the number of positions the order_buf head has moved
+ */
+
+ struct cir_buffer *order_buf = &b->order_buf,
+ *ready_buf = &b->ready_buf;
+
+ unsigned int order_head_adv = 0;
+
+ /*
+ * move at least n packets to ready buffer, assuming ready buffer
+ * has room for those packets.
+ */
+ while (order_head_adv < n &&
+ ((ready_buf->head + 1) & ready_buf->mask) != ready_buf->tail) {
+
+ /* if we are blocked waiting on a packet, skip it */
+ if (order_buf->entries[order_buf->head] == NULL) {
+ order_buf->head = (order_buf->head + 1) & order_buf->mask;
+ order_head_adv++;
+ }
+
+ /* Move all ready entries that fit to the ready_buf */
+ while (order_buf->entries[order_buf->head] != NULL) {
+ ready_buf->entries[ready_buf->head] =
+ order_buf->entries[order_buf->head];
+
+ order_buf->entries[order_buf->head] = NULL;
+ order_head_adv++;
+
+ order_buf->head = (order_buf->head + 1) & order_buf->mask;
+
+ if (((ready_buf->head + 1) & ready_buf->mask) == ready_buf->tail)
+ break;
+
+ ready_buf->head = (ready_buf->head + 1) & ready_buf->mask;
+ }
+ }
+
+ b->min_seqn += order_head_adv;
+ /* Return the number of positions the order_buf head has moved */
+ return order_head_adv;
+}
+
+int
+rte_reorder_insert(struct rte_reorder_buffer *b, struct rte_mbuf *mbuf)
+{
+ uint32_t offset, position;
+ struct cir_buffer *order_buf = &b->order_buf;
+
+ /*
+ * calculate the offset from the head pointer we need to go.
+ * The subtraction takes care of the sequence number wrapping.
+ * For example (using 16-bit for brevity):
+ * min_seqn = 0xFFFD
+ * mbuf_seqn = 0x0010
+ * offset = 0x0010 - 0xFFFD = 0x13
+ */
+ offset = mbuf->seqn - b->min_seqn;
+
+ /*
+ * action to take depends on offset.
+ * offset < buffer->size: the mbuf fits within the current window of
+ * sequence numbers we can reorder. EXPECTED CASE.
+ * offset > buffer->size: the mbuf is outside the current window. There
+ * are a number of cases to consider:
+ * 1. The packet sequence is just outside the window, then we need
+ * to see about shifting the head pointer and taking any ready
+ * to return packets out of the ring. If there was a delayed
+ * or dropped packet preventing drains from shifting the window
+ * this case will skip over the dropped packet instead, and any
+ * packets dequeued here will be returned on the next drain call.
+ * 2. The packet sequence number is vastly outside our window, taken
+ * here as having offset greater than twice the buffer size. In
+ * this case, the packet is probably an old or late packet that
+ * was previously skipped, so just enqueue the packet for
+ * immediate return on the next drain call, or else return error.
+ */
+ if (offset < b->order_buf.size) {
+ position = (order_buf->head + offset) & order_buf->mask;
+ order_buf->entries[position] = mbuf;
+ } else if (offset < 2 * b->order_buf.size) {
+ if (rte_reorder_fill_overflow(b, offset + 1 - order_buf->size)
+ < (offset + 1 - order_buf->size)) {
+ /* Put in handling for enqueue straight to output */
+ rte_errno = ENOSPC;
+ return -1;
+ }
+ offset = mbuf->seqn - b->min_seqn;
+ position = (order_buf->head + offset) & order_buf->mask;
+ order_buf->entries[position] = mbuf;
+ } else {
+ /* Put in handling for enqueue straight to output */
+ rte_errno = ERANGE;
+ return -1;
+ }
+ return 0;
+}
+
+unsigned int
+rte_reorder_drain(struct rte_reorder_buffer *b, struct rte_mbuf **mbufs,
+ unsigned max_mbufs)
+{
+ unsigned int drain_cnt = 0;
+
+ struct cir_buffer *order_buf = &b->order_buf,
+ *ready_buf = &b->ready_buf;
+
+ /* Try to fetch requested number of mbufs from ready buffer */
+ while ((drain_cnt < max_mbufs) && (ready_buf->tail != ready_buf->head)) {
+ mbufs[drain_cnt++] = ready_buf->entries[ready_buf->tail];
+ ready_buf->tail = (ready_buf->tail + 1) & ready_buf->mask;
+ }
+
+ /*
+ * If requested number of buffers not fetched from ready buffer, fetch
+ * remaining buffers from order buffer
+ */
+ while ((drain_cnt < max_mbufs) &&
+ (order_buf->entries[order_buf->head] != NULL)) {
+ mbufs[drain_cnt++] = order_buf->entries[order_buf->head];
+ order_buf->entries[order_buf->head] = NULL;
+ b->min_seqn++;
+ order_buf->head = (order_buf->head + 1) & order_buf->mask;
+ }
+
+ return drain_cnt;
+}
diff --git a/lib/librte_reorder/rte_reorder.h b/lib/librte_reorder/rte_reorder.h
new file mode 100644
index 0000000..8300bf0
--- /dev/null
+++ b/lib/librte_reorder/rte_reorder.h
@@ -0,0 +1,181 @@
+/*-
+ * 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 _RTE_REORDER_H_
+#define _RTE_REORDER_H_
+
+/**
+ * @file
+ * RTE reorder
+ *
+ * Reorder library is a component which is designed to
+ * provide ordering of out of ordered packets based on
+ * sequence number present in mbuf.
+ *
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct rte_reorder_buffer;
+
+/**
+ * Create a new reorder buffer instance
+ *
+ * Allocate memory and initialize a new reorder buffer in that
+ * memory, returning the reorder buffer pointer to the user
+ *
+ * @param name
+ * The name to be given to the reorder buffer instance.
+ * @param socket_id
+ * The NUMA node on which the memory for the reorder buffer
+ * instance is to be reserved.
+ * @param size
+ * Max number of elements that can be stored in the reorder buffer
+ * @return
+ * The initialized reorder buffer instance, or NULL on error
+ * On error case, rte_errno will be set appropriately:
+ * - ENOMEM - no appropriate memory area found in which to create memzone
+ * - EINVAL - invalid parameters
+ */
+struct rte_reorder_buffer *
+rte_reorder_create(const char *name, unsigned socket_id, unsigned int size);
+
+/**
+ * Initializes given reorder buffer instance
+ *
+ * @param b
+ * Reorder buffer instance to initialize
+ * @param bufsize
+ * Size of the reorder buffer
+ * @param name
+ * The name to be given to the reorder buffer
+ * @param size
+ * Number of elements that can be stored in reorder buffer
+ * @return
+ * The initialized reorder buffer instance, or NULL on error
+ * On error case, rte_errno will be set appropriately:
+ * - EINVAL - invalid parameters
+ */
+struct rte_reorder_buffer *
+rte_reorder_init(struct rte_reorder_buffer *b, unsigned int bufsize,
+ const char *name, unsigned int size);
+
+/**
+ * Find an existing reorder buffer instance
+ * and return a pointer to it.
+ *
+ * @param name
+ * Name of the reorder buffer instacne as passed to rte_reorder_create()
+ * @return
+ * Pointer to reorder buffer instance or NULL if object not found with rte_errno
+ * set appropriately. Possible rte_errno values include:
+ * - ENOENT - required entry not available to return.
+ * - E_RTE_NO_TAILQ - no tailq list could be got for the
+ * reorder instance list
+ */
+struct rte_reorder_buffer *
+rte_reorder_find_existing(const char *name);
+
+/**
+ * Reset the given reorder buffer instance with initial values.
+ *
+ * @param b
+ * Reorder buffer instance which has to be reset
+ */
+void
+rte_reorder_reset(struct rte_reorder_buffer *b);
+
+/**
+ * Free reorder buffer instance.
+ *
+ * @param b
+ * reorder buffer instance
+ * @return
+ * None
+ */
+void
+rte_reorder_free(struct rte_reorder_buffer *b);
+
+/**
+ * Insert given mbuf in reorder buffer in its correct position
+ *
+ * The given mbuf is to be reordered relative to other mbufs in the system.
+ * The mbuf must contain a sequence number which is then used to place
+ * the buffer in the correct position in the reorder buffer. Reordered
+ * packets can later be taken from the buffer using the rte_reorder_drain()
+ * API.
+ *
+ * @param b
+ * Reorder buffer where the mbuf has to be inserted.
+ * @param mbuf
+ * mbuf of packet that needs to be inserted in reorder buffer.
+ * @return
+ * 0 on success
+ * -1 on error
+ * On error case, rte_errno will be set appropriately:
+ * - ENOSPC - Cannot move existing mbufs from reorder buffer to accommodate
+ * ealry mbuf, but it can be accomodated by performing drain and then insert.
+ * - ERANGE - Too early or late mbuf which is vastly out of range of expected
+ * window should be ingnored without any handling.
+ */
+int
+rte_reorder_insert(struct rte_reorder_buffer *b, struct rte_mbuf *mbuf);
+
+/**
+ * Fetch reordered buffers
+ *
+ * Returns a set of in-order buffers from the reorder buffer structure. Gaps
+ * may be present in the sequence numbers of the mbuf if packets have been
+ * delayed too long before reaching the reorder window, or have been previously
+ * dropped by the system.
+ *
+ * @param b
+ * Reorder buffer instance from which packets are to be drained
+ * @param mbufs
+ * array of mbufs where reordered packets will be inserted from reorder buffer
+ * @param max_mbufs
+ * the number of elements in the mbufs array.
+ * @return
+ * number of mbuf pointers written to mbufs. 0 <= N < max_mbufs.
+ */
+unsigned int
+rte_reorder_drain(struct rte_reorder_buffer *b, struct rte_mbuf **mbufs,
+ unsigned max_mbufs);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_REORDER_H_ */
diff --git a/lib/librte_reorder/rte_reorder_version.map b/lib/librte_reorder/rte_reorder_version.map
new file mode 100644
index 0000000..0a8a54d
--- /dev/null
+++ b/lib/librte_reorder/rte_reorder_version.map
@@ -0,0 +1,13 @@
+DPDK_2.0 {
+ global:
+
+ rte_reorder_create;
+ rte_reorder_init;
+ rte_reorder_find_existing;
+ rte_reorder_reset;
+ rte_reorder_free;
+ rte_reorder_insert;
+ rte_reorder_drain;
+
+ local: *;
+};