[dpdk-dev] [PATCH v7 1/6] lib: add information metrics library

[Remy Horton <remy.horton@intel.com>]

This patch adds a new information metric library that allows other
modules to register named metrics and update their values. It is
intended to be independent of ethdev, rather than mixing ethdev
and non-ethdev information in xstats.

Signed-off-by: Remy Horton <remy.horton@intel.com>
---
 MAINTAINERS                                |   5 +
 config/common_base                         |   5 +
 doc/api/doxy-api-index.md                  |   1 +
 doc/api/doxy-api.conf                      |   1 +
 doc/guides/rel_notes/release_17_02.rst     |   8 +
 lib/Makefile                               |   1 +
 lib/librte_metrics/Makefile                |  51 +++++
 lib/librte_metrics/rte_metrics.c           | 310 +++++++++++++++++++++++++++++
 lib/librte_metrics/rte_metrics.h           | 223 +++++++++++++++++++++
 lib/librte_metrics/rte_metrics_version.map |  13 ++
 mk/rte.app.mk                              |   2 +
 11 files changed, 620 insertions(+)
 create mode 100644 lib/librte_metrics/Makefile
 create mode 100644 lib/librte_metrics/rte_metrics.c
 create mode 100644 lib/librte_metrics/rte_metrics.h
 create mode 100644 lib/librte_metrics/rte_metrics_version.map

diff --git a/MAINTAINERS b/MAINTAINERS
index 9645c9b..4a19497 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -596,6 +596,11 @@ F: lib/librte_jobstats/
 F: examples/l2fwd-jobstats/
 F: doc/guides/sample_app_ug/l2_forward_job_stats.rst
 
+Metrics
+M: Remy Horton <remy.horton@intel.com>
+F: lib/librte_metrics/
+F: doc/guides/sample_app_ug/keep_alive.rst
+
 
 Test Applications
 -----------------
diff --git a/config/common_base b/config/common_base
index 8e9dcfa..0eb3866 100644
--- a/config/common_base
+++ b/config/common_base
@@ -593,3 +593,8 @@ CONFIG_RTE_APP_TEST_RESOURCE_TAR=n
 CONFIG_RTE_TEST_PMD=y
 CONFIG_RTE_TEST_PMD_RECORD_CORE_CYCLES=n
 CONFIG_RTE_TEST_PMD_RECORD_BURST_STATS=n
+
+#
+# Compile the device metrics library
+#
+CONFIG_RTE_LIBRTE_METRICS=y
diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
index 72d59b2..94f0f69 100644
--- a/doc/api/doxy-api-index.md
+++ b/doc/api/doxy-api-index.md
@@ -150,4 +150,5 @@ There are many libraries, so their headers may be grouped by topics:
   [common]             (@ref rte_common.h),
   [ABI compat]         (@ref rte_compat.h),
   [keepalive]          (@ref rte_keepalive.h),
+  [Device Metrics]     (@ref rte_metrics.h),
   [version]            (@ref rte_version.h)
diff --git a/doc/api/doxy-api.conf b/doc/api/doxy-api.conf
index b340fcf..194b670 100644
--- a/doc/api/doxy-api.conf
+++ b/doc/api/doxy-api.conf
@@ -50,6 +50,7 @@ INPUT                   = doc/api/doxy-api-index.md \
                           lib/librte_mbuf \
                           lib/librte_mempool \
                           lib/librte_meter \
+                          lib/librte_metrics \
                           lib/librte_net \
                           lib/librte_pdump \
                           lib/librte_pipeline \
diff --git a/doc/guides/rel_notes/release_17_02.rst b/doc/guides/rel_notes/release_17_02.rst
index d445d64..4fca29b 100644
--- a/doc/guides/rel_notes/release_17_02.rst
+++ b/doc/guides/rel_notes/release_17_02.rst
@@ -34,6 +34,12 @@ New Features
 
      Refer to the previous release notes for examples.
 
+   * **Added information metric library.**
+
+     A library that allows information metrics to be added and update. It is
+     intended to provide a reporting mechanism that is independent of the
+     ethdev library.
+
      This section is a comment. do not overwrite or remove it.
      Also, make sure to start the actual text at the margin.
      =========================================================
@@ -161,6 +167,7 @@ The libraries prepended with a plus sign were incremented in this version.
 .. code-block:: diff
 
      librte_acl.so.2
+   + librte_bitratestats.so.1
      librte_cfgfile.so.2
      librte_cmdline.so.2
      librte_cryptodev.so.2
@@ -176,6 +183,7 @@ The libraries prepended with a plus sign were incremented in this version.
      librte_mbuf.so.2
      librte_mempool.so.2
      librte_meter.so.1
+   + librte_metrics.so.1
      librte_net.so.1
      librte_pdump.so.1
      librte_pipeline.so.3
diff --git a/lib/Makefile b/lib/Makefile
index 990f23a..5d85dcf 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -58,6 +58,7 @@ DIRS-$(CONFIG_RTE_LIBRTE_TABLE) += librte_table
 DIRS-$(CONFIG_RTE_LIBRTE_PIPELINE) += librte_pipeline
 DIRS-$(CONFIG_RTE_LIBRTE_REORDER) += librte_reorder
 DIRS-$(CONFIG_RTE_LIBRTE_PDUMP) += librte_pdump
+DIRS-$(CONFIG_RTE_LIBRTE_METRICS) += librte_metrics
 
 ifeq ($(CONFIG_RTE_EXEC_ENV_LINUXAPP),y)
 DIRS-$(CONFIG_RTE_LIBRTE_KNI) += librte_kni
diff --git a/lib/librte_metrics/Makefile b/lib/librte_metrics/Makefile
new file mode 100644
index 0000000..8d6e23a
--- /dev/null
+++ b/lib/librte_metrics/Makefile
@@ -0,0 +1,51 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2016 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_metrics.a
+
+CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR)
+
+EXPORT_MAP := rte_metrics_version.map
+
+LIBABIVER := 1
+
+# all source are stored in SRCS-y
+SRCS-$(CONFIG_RTE_LIBRTE_METRICS) := rte_metrics.c
+
+# Install header file
+SYMLINK-$(CONFIG_RTE_LIBRTE_METRICS)-include += rte_metrics.h
+
+DEPDIRS-$(CONFIG_RTE_LIBRTE_METRICS) += lib/librte_eal
+
+include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/lib/librte_metrics/rte_metrics.c b/lib/librte_metrics/rte_metrics.c
new file mode 100644
index 0000000..5072f4d
--- /dev/null
+++ b/lib/librte_metrics/rte_metrics.c
@@ -0,0 +1,310 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2016 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 <string.h>
+#include <sys/queue.h>
+
+#include <rte_common.h>
+#include <rte_malloc.h>
+#include <rte_metrics.h>
+#include <rte_lcore.h>
+#include <rte_memzone.h>
+#include <rte_spinlock.h>
+
+#define RTE_METRICS_MAX_METRICS 256
+#define RTE_METRICS_MEMZONE_NAME "RTE_METRICS"
+
+/**
+ * Internal stats metadata and value entry.
+ *
+ * @internal
+ * @param name
+ *   Name of metric
+ * @param value
+ *   Current value for metric
+ * @param idx_next_set
+ *   Index of next root element (zero for none)
+ * @param idx_next_metric
+ *   Index of next metric in set (zero for none)
+ *
+ * Only the root of each set needs idx_next_set but since it has to be
+ * assumed that number of sets could equal total number of metrics,
+ * having a separate set metadata table doesn't save any memory.
+ */
+struct rte_metrics_meta_s {
+	char name[RTE_METRICS_MAX_NAME_LEN];
+	uint64_t value[RTE_MAX_ETHPORTS];
+	uint64_t nonport_value;
+	uint16_t idx_next_set;
+	uint16_t idx_next_stat;
+};
+
+/**
+ * Internal stats info structure.
+ *
+ * @internal
+ * @param idx_last_set
+ *   Index of last metadata entry with valid data. This value is
+ *   not valid if cnt_stats is zero.
+ * @param cnt_stats
+ *   Number of metrics.
+ * @param metadata
+ *   Stat data memory block.
+ *
+ * Offsets into metadata are used instead of pointers because ASLR
+ * means that having the same physical addresses in different
+ * processes is not guaranteed.
+ */
+struct rte_metrics_data_s {
+	uint16_t idx_last_set;
+	uint16_t cnt_stats;
+	struct rte_metrics_meta_s metadata[RTE_METRICS_MAX_METRICS];
+	rte_spinlock_t lock;
+};
+
+void
+rte_metrics_init(void)
+{
+	struct rte_metrics_data_s *stats;
+	const struct rte_memzone *memzone;
+
+	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
+		return;
+
+	memzone = rte_memzone_lookup(RTE_METRICS_MEMZONE_NAME);
+	if (memzone != NULL)
+		return;
+	memzone = rte_memzone_reserve(RTE_METRICS_MEMZONE_NAME,
+		sizeof(struct rte_metrics_data_s), rte_socket_id(), 0);
+	if (memzone == NULL)
+		rte_exit(EXIT_FAILURE, "Unable to allocate stats memzone\n");
+	stats = memzone->addr;
+	memset(stats, 0, sizeof(struct rte_metrics_data_s));
+	rte_spinlock_init(&stats->lock);
+}
+
+int
+rte_metrics_reg_metric(const char *name)
+{
+	const char * const list_names[] = {name};
+
+	return rte_metrics_reg_metrics(list_names, 1);
+}
+
+int
+rte_metrics_reg_metrics(const char * const *names, uint16_t cnt_names)
+{
+	struct rte_metrics_meta_s *entry;
+	struct rte_metrics_data_s *stats;
+	const struct rte_memzone *memzone;
+	uint16_t idx_name;
+	uint16_t idx_base;
+
+	/* Some sanity checks */
+	if (cnt_names < 1 || names == NULL)
+		return -EINVAL;
+
+	rte_metrics_init();
+	memzone = rte_memzone_lookup(RTE_METRICS_MEMZONE_NAME);
+	if (memzone == NULL)
+		return -EIO;
+	stats = memzone->addr;
+
+	if (stats->cnt_stats + cnt_names >= RTE_METRICS_MAX_METRICS)
+		return -ENOMEM;
+
+	rte_spinlock_lock(&stats->lock);
+
+	/* Overwritten later if this is actually first set.. */
+	stats->metadata[stats->idx_last_set].idx_next_set = stats->cnt_stats;
+
+	stats->idx_last_set = idx_base = stats->cnt_stats;
+
+	for (idx_name = 0; idx_name < cnt_names; idx_name++) {
+		entry = &stats->metadata[idx_name + stats->cnt_stats];
+		strncpy(entry->name, names[idx_name],
+			RTE_METRICS_MAX_NAME_LEN);
+		memset(entry->value, 0, sizeof(entry->value));
+		entry->idx_next_stat = idx_name + stats->cnt_stats + 1;
+	}
+	entry->idx_next_stat = 0;
+	entry->idx_next_set = 0;
+	stats->cnt_stats += cnt_names;
+
+	rte_spinlock_unlock(&stats->lock);
+
+	return idx_base;
+}
+
+int
+rte_metrics_update_metric(int port_id, uint16_t key, const uint64_t value)
+{
+	return rte_metrics_update_metrics(port_id, key, &value, 1);
+}
+
+int
+rte_metrics_update_metrics(int port_id,
+	uint16_t key,
+	const uint64_t *values,
+	uint32_t count)
+{
+	struct rte_metrics_meta_s *entry;
+	struct rte_metrics_data_s *stats;
+	const struct rte_memzone *memzone;
+	uint16_t idx_metric;
+	uint16_t idx_value;
+	uint16_t cnt_setsize;
+
+	if (port_id != RTE_METRICS_GLOBAL &&
+			(port_id < 0 || port_id > RTE_MAX_ETHPORTS))
+		return -EINVAL;
+
+	rte_metrics_init();
+	memzone = rte_memzone_lookup(RTE_METRICS_MEMZONE_NAME);
+	if (memzone == NULL)
+		return -EIO;
+	stats = memzone->addr;
+
+	rte_spinlock_lock(&stats->lock);
+	idx_metric = key;
+	cnt_setsize = 1;
+	while (idx_metric < stats->cnt_stats) {
+		entry = &stats->metadata[idx_metric];
+		if (entry->idx_next_stat == 0)
+			break;
+		cnt_setsize++;
+		idx_metric++;
+	}
+	/* Check update does not cross set border */
+	if (count > cnt_setsize) {
+		rte_spinlock_unlock(&stats->lock);
+		return -ERANGE;
+	}
+
+	if (port_id == RTE_METRICS_GLOBAL)
+		for (idx_value = 0; idx_value < count; idx_value++) {
+			idx_metric = key + idx_value;
+			stats->metadata[idx_metric].nonport_value =
+				values[idx_value];
+		}
+	else
+		for (idx_value = 0; idx_value < count; idx_value++) {
+			idx_metric = key + idx_value;
+			stats->metadata[idx_metric].value[port_id] =
+				values[idx_value];
+		}
+	rte_spinlock_unlock(&stats->lock);
+	return 0;
+}
+
+int
+rte_metrics_get_names(struct rte_metric_name *names,
+	uint16_t capacity)
+{
+	struct rte_metrics_data_s *stats;
+	const struct rte_memzone *memzone;
+	uint16_t idx_name;
+	int return_value;
+
+	memzone = rte_memzone_lookup(RTE_METRICS_MEMZONE_NAME);
+	/* If not allocated, fail silently */
+	if (memzone == NULL)
+		return 0;
+
+	stats = memzone->addr;
+	rte_spinlock_lock(&stats->lock);
+	if (names != NULL) {
+		if (capacity < stats->cnt_stats) {
+			return_value = stats->cnt_stats;
+			rte_spinlock_unlock(&stats->lock);
+			return return_value;
+		}
+		for (idx_name = 0; idx_name < stats->cnt_stats; idx_name++)
+			strncpy(names[idx_name].name,
+				stats->metadata[idx_name].name,
+				RTE_METRICS_MAX_NAME_LEN);
+	}
+	return_value = stats->cnt_stats;
+	rte_spinlock_unlock(&stats->lock);
+	return return_value;
+}
+
+int
+rte_metrics_get_values(int port_id,
+	struct rte_metric_value *values,
+	uint16_t capacity)
+{
+	struct rte_metrics_meta_s *entry;
+	struct rte_metrics_data_s *stats;
+	const struct rte_memzone *memzone;
+	uint16_t idx_name;
+	int return_value;
+
+	if (port_id != RTE_METRICS_GLOBAL &&
+			(port_id < 0 || port_id > RTE_MAX_ETHPORTS))
+		return -EINVAL;
+
+	memzone = rte_memzone_lookup(RTE_METRICS_MEMZONE_NAME);
+	/* If not allocated, fail silently */
+	if (memzone == NULL)
+		return 0;
+	stats = memzone->addr;
+	rte_spinlock_lock(&stats->lock);
+
+	if (values != NULL) {
+		if (capacity < stats->cnt_stats) {
+			return_value = stats->cnt_stats;
+			rte_spinlock_unlock(&stats->lock);
+			return return_value;
+		}
+		if (port_id == RTE_METRICS_GLOBAL)
+			for (idx_name = 0;
+					idx_name < stats->cnt_stats;
+					idx_name++) {
+				entry = &stats->metadata[idx_name];
+				values[idx_name].key = idx_name;
+				values[idx_name].value = entry->nonport_value;
+			}
+		else
+			for (idx_name = 0;
+					idx_name < stats->cnt_stats;
+					idx_name++) {
+				entry = &stats->metadata[idx_name];
+				values[idx_name].key = idx_name;
+				values[idx_name].value = entry->value[port_id];
+			}
+	}
+	return_value = stats->cnt_stats;
+	rte_spinlock_unlock(&stats->lock);
+	return return_value;
+}
diff --git a/lib/librte_metrics/rte_metrics.h b/lib/librte_metrics/rte_metrics.h
new file mode 100644
index 0000000..fd82af9
--- /dev/null
+++ b/lib/librte_metrics/rte_metrics.h
@@ -0,0 +1,223 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2016 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.
+ */
+
+/**
+ * @file
+ *
+ * RTE Metrics module
+ *
+ * Metric information is populated using a push model, where the
+ * information provider calls an update function on the relevant
+ * metrics. Currently only bulk querying of metrics is supported.
+ */
+
+#ifndef _RTE_METRICS_H_
+#define _RTE_METRICS_H_
+
+/** Maximum length of metric name (including null-terminator) */
+#define RTE_METRICS_MAX_NAME_LEN 64
+
+/**
+ * Global (rather than port-specific) metric.
+ *
+ * When used instead of port number by rte_metrics_update_metric()
+ * or rte_metrics_update_metric(), the global metrics, which are
+ * not associated with any specific port, are updated.
+ */
+#define RTE_METRICS_GLOBAL -1
+
+
+/**
+ * A name-key lookup for metrics.
+ *
+ * An array of this structure is returned by rte_metrics_get_names().
+ * The struct rte_eth_stats references these names via their array index.
+ */
+struct rte_metric_name {
+	/** String describing metric */
+	char name[RTE_METRICS_MAX_NAME_LEN];
+};
+
+
+/**
+ * Metric value structure.
+ *
+ * This structure is used by rte_metrics_get_values() to return metrics,
+ * which are statistics that are not generated by PMDs. It maps a name key,
+ * which corresponds to an index in the array returned by
+ * rte_metrics_get_names().
+ */
+struct rte_metric_value {
+	/** Numeric identifier of metric. */
+	uint16_t key;
+	/** Value for metric */
+	uint64_t value;
+};
+
+
+/**
+ * Initializes metric module. This only has to be explicitly called if you
+ * intend to use rte_metrics_reg_metric() or rte_metrics_reg_metrics() from a
+ * secondary process. This function must be called from a primary process.
+ */
+void rte_metrics_init(void);
+
+/**
+ * Register a metric, making it available as a reporting parameter.
+ *
+ * Registering a metric is the way third-parties declare a parameter
+ * that they wish to be reported. Once registered, the associated
+ * numeric key can be obtained via rte_metrics_get_names(), which
+ * is required for updating said metric's value.
+ *
+ * @param name
+ *   Metric name
+ *
+ * @return
+ *  - Zero or positive: Success
+ *  - Negative: Failure
+ */
+int rte_metrics_reg_metric(const char *name);
+
+/**
+ * Register a set of metrics.
+ *
+ * This is a bulk version of rte_metrics_reg_metrics() and aside from
+ * handling multiple keys at once is functionally identical.
+ *
+ * @param names
+ *   List of metric names
+ *
+ * @param cnt_names
+ *   Number of metrics in set
+ *
+ * @return
+ *  - Zero or positive: Success
+ *  - Negative: Failure
+ */
+int rte_metrics_reg_metrics(const char * const *names, uint16_t cnt_names);
+
+/**
+ * Get metric name-key lookup table.
+ *
+ * @param names
+ *   A struct rte_metric_name array of at least *capacity* in size to
+ *   receive key names. If this is NULL, function returns the required
+ *   number of elements for this array.
+ *
+ * @param capacity
+ *   Size (number of elements) of struct rte_metric_name array.
+ *   Disregarded if names is NULL.
+ *
+ * @return
+ *   - Positive value above capacity: error, *names* is too small.
+ *     Return value is required size.
+ *   - Positive value equal or less than capacity: Success. Return
+ *     value is number of elements filled in.
+ *   - Negative value: error.
+ */
+int rte_metrics_get_names(
+	struct rte_metric_name *names,
+	uint16_t capacity);
+
+/**
+ * Get metric value table.
+ *
+ * @param port_id
+ *   Port id to query
+ *
+ * @param values
+ *   A struct rte_metric_value array of at least *capacity* in size to
+ *   receive metric ids and values. If this is NULL, function returns
+ *   the required number of elements for this array.
+ *
+ * @param capacity
+ *   Size (number of elements) of struct rte_metric_value array.
+ *   Disregarded if names is NULL.
+ *
+ * @return
+ *   - Positive value above capacity: error, *values* is too small.
+ *     Return value is required size.
+ *   - Positive value equal or less than capacity: Success. Return
+ *     value is number of elements filled in.
+ *   - Negative value: error.
+ */
+int rte_metrics_get_values(
+	int port_id,
+	struct rte_metric_value *values,
+	uint16_t capacity);
+
+/**
+ * Updates a metric
+ *
+ * @param port_id
+ *   Port to update metrics for
+ * @param key
+ *   Id of metric to update
+ * @param value
+ *   New value
+ *
+ * @return
+ *   - -EIO if unable to access shared metrics memory
+ *   - Zero on success
+ */
+int rte_metrics_update_metric(
+	int port_id,
+	uint16_t key,
+	const uint64_t value);
+
+/**
+ * Updates a metric set. Note that it is an error to try to
+ * update across a set boundary.
+ *
+ * @param port_id
+ *   Port to update metrics for
+ * @param key
+ *   Base id of metrics set to update
+ * @param values
+ *   Set of new values
+ * @param count
+ *   Number of new values
+ *
+ * @return
+ *   - -ERANGE if count exceeds metric set size
+ *   - -EIO if upable to access shared metrics memory
+ *   - Zero on success
+ */
+int rte_metrics_update_metrics(
+	int port_id,
+	uint16_t key,
+	const uint64_t *values,
+	uint32_t count);
+
+#endif
diff --git a/lib/librte_metrics/rte_metrics_version.map b/lib/librte_metrics/rte_metrics_version.map
new file mode 100644
index 0000000..f904814
--- /dev/null
+++ b/lib/librte_metrics/rte_metrics_version.map
@@ -0,0 +1,13 @@
+DPDK_17.02 {
+	global:
+
+	rte_metrics_get_names;
+	rte_metrics_get_values;
+	rte_metrics_init;
+	rte_metrics_reg_metric;
+	rte_metrics_reg_metrics;
+	rte_metrics_update_metric;
+	rte_metrics_update_metrics;
+
+	local: *;
+};
diff --git a/mk/rte.app.mk b/mk/rte.app.mk
index f75f0e2..40fcf33 100644
--- a/mk/rte.app.mk
+++ b/mk/rte.app.mk
@@ -98,6 +98,8 @@ _LDLIBS-$(CONFIG_RTE_LIBRTE_RING)           += -lrte_ring
 _LDLIBS-$(CONFIG_RTE_LIBRTE_EAL)            += -lrte_eal
 _LDLIBS-$(CONFIG_RTE_LIBRTE_CMDLINE)        += -lrte_cmdline
 _LDLIBS-$(CONFIG_RTE_LIBRTE_CFGFILE)        += -lrte_cfgfile
+_LDLIBS-$(CONFIG_RTE_LIBRTE_METRICS)        += -lrte_metrics
+
 
 _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_BOND)       += -lrte_pmd_bond
 _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_XENVIRT)    += -lrte_pmd_xenvirt -lxenstore
-- 
2.5.5