[dpdk-dev] [PATCH v4 04/10] rawdev: support for extended stats

[Shreyansh Jain <shreyansh.jain@nxp.com>]

Generic rawdev library cannot define a pre-defined set of stats
for devices which are yet to be defined.

This patch introduces the xstats support for rawdev so that any
implementation can create its own statistics.

Signed-off-by: Shreyansh Jain <shreyansh.jain@nxp.com>
---
 lib/librte_rawdev/rte_rawdev.c           |  75 ++++++++++++++++++++++
 lib/librte_rawdev/rte_rawdev.h           | 105 +++++++++++++++++++++++++++++++
 lib/librte_rawdev/rte_rawdev_pmd.h       |  72 +++++++++++++++++++++
 lib/librte_rawdev/rte_rawdev_version.map |   4 ++
 4 files changed, 256 insertions(+)

diff --git a/lib/librte_rawdev/rte_rawdev.c b/lib/librte_rawdev/rte_rawdev.c
index a6d937c34..d6c284554 100644
--- a/lib/librte_rawdev/rte_rawdev.c
+++ b/lib/librte_rawdev/rte_rawdev.c
@@ -245,6 +245,81 @@ rte_rawdev_dump(uint16_t dev_id, FILE *f)
 	return (*dev->dev_ops->dump)(dev, f);
 }
 
+static int
+xstats_get_count(uint16_t dev_id)
+{
+	struct rte_rawdev *dev = &rte_rawdevs[dev_id];
+
+	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->xstats_get_names, -ENOTSUP);
+	return (*dev->dev_ops->xstats_get_names)(dev, NULL, 0);
+}
+
+int __rte_experimental
+rte_rawdev_xstats_names_get(uint16_t dev_id,
+		struct rte_rawdev_xstats_name *xstats_names,
+		unsigned int size)
+{
+	const struct rte_rawdev *dev;
+	int cnt_expected_entries;
+
+	RTE_RAWDEV_VALID_DEVID_OR_ERR_RET(dev_id, -ENODEV);
+
+	cnt_expected_entries = xstats_get_count(dev_id);
+
+	if (xstats_names == NULL || cnt_expected_entries < 0 ||
+	    (int)size < cnt_expected_entries || size <= 0)
+		return cnt_expected_entries;
+
+	dev = &rte_rawdevs[dev_id];
+
+	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->xstats_get_names, -ENOTSUP);
+	return (*dev->dev_ops->xstats_get_names)(dev, xstats_names, size);
+}
+
+/* retrieve rawdev extended statistics */
+int __rte_experimental
+rte_rawdev_xstats_get(uint16_t dev_id,
+		      const unsigned int ids[],
+		      uint64_t values[],
+		      unsigned int n)
+{
+	RTE_RAWDEV_VALID_DEVID_OR_ERR_RET(dev_id, -ENODEV);
+	const struct rte_rawdev *dev = &rte_rawdevs[dev_id];
+
+	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->xstats_get, -ENOTSUP);
+	return (*dev->dev_ops->xstats_get)(dev, ids, values, n);
+}
+
+uint64_t __rte_experimental
+rte_rawdev_xstats_by_name_get(uint16_t dev_id,
+			      const char *name,
+			      unsigned int *id)
+{
+	RTE_RAWDEV_VALID_DEVID_OR_ERR_RET(dev_id, 0);
+	const struct rte_rawdev *dev = &rte_rawdevs[dev_id];
+	unsigned int temp = -1;
+
+	if (id != NULL)
+		*id = (unsigned int)-1;
+	else
+		id = &temp; /* driver never gets a NULL value */
+
+	/* implemented by driver */
+	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->xstats_get_by_name, -ENOTSUP);
+	return (*dev->dev_ops->xstats_get_by_name)(dev, name, id);
+}
+
+int __rte_experimental
+rte_rawdev_xstats_reset(uint16_t dev_id,
+			const uint32_t ids[], uint32_t nb_ids)
+{
+	RTE_RAWDEV_VALID_DEVID_OR_ERR_RET(dev_id, -EINVAL);
+	struct rte_rawdev *dev = &rte_rawdevs[dev_id];
+
+	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->xstats_reset, -ENOTSUP);
+	return (*dev->dev_ops->xstats_reset)(dev, ids, nb_ids);
+}
+
 int __rte_experimental
 rte_rawdev_start(uint16_t dev_id)
 {
diff --git a/lib/librte_rawdev/rte_rawdev.h b/lib/librte_rawdev/rte_rawdev.h
index 3820ff08d..28bf9e0ff 100644
--- a/lib/librte_rawdev/rte_rawdev.h
+++ b/lib/librte_rawdev/rte_rawdev.h
@@ -420,6 +420,111 @@ rte_rawdev_dequeue_buffers(uint16_t dev_id,
 			   unsigned int count,
 			   rte_rawdev_obj_t context);
 
+/** Maximum name length for extended statistics counters */
+#define RTE_RAW_DEV_XSTATS_NAME_SIZE 64
+
+/**
+ * A name-key lookup element for extended statistics.
+ *
+ * This structure is used to map between names and ID numbers
+ * for extended ethdev statistics.
+ */
+struct rte_rawdev_xstats_name {
+	char name[RTE_RAW_DEV_XSTATS_NAME_SIZE];
+};
+
+/**
+ * Retrieve names of extended statistics of a raw device.
+ *
+ * @param dev_id
+ *   The identifier of the raw device.
+ * @param[out] xstats_names
+ *   Block of memory to insert names into. Must be at least size in capacity.
+ *   If set to NULL, function returns required capacity.
+ * @param size
+ *   Capacity of xstats_names (number of names).
+ * @return
+ *   - positive value lower or equal to size: success. The return value
+ *     is the number of entries filled in the stats table.
+ *   - positive value higher than size: error, the given statistics table
+ *     is too small. The return value corresponds to the size that should
+ *     be given to succeed. The entries in the table are not valid and
+ *     shall not be used by the caller.
+ *   - negative value on error:
+ *        -ENODEV for invalid *dev_id*
+ *        -ENOTSUP if the device doesn't support this function.
+ */
+int __rte_experimental
+rte_rawdev_xstats_names_get(uint16_t dev_id,
+			    struct rte_rawdev_xstats_name *xstats_names,
+			    unsigned int size);
+
+/**
+ * Retrieve extended statistics of a raw device.
+ *
+ * @param dev_id
+ *   The identifier of the device.
+ * @param ids
+ *   The id numbers of the stats to get. The ids can be got from the stat
+ *   position in the stat list from rte_rawdev_get_xstats_names(), or
+ *   by using rte_rawdev_get_xstats_by_name()
+ * @param[out] values
+ *   The values for each stats request by ID.
+ * @param n
+ *   The number of stats requested
+ * @return
+ *   - positive value: number of stat entries filled into the values array
+ *   - negative value on error:
+ *        -ENODEV for invalid *dev_id*
+ *        -ENOTSUP if the device doesn't support this function.
+ */
+int __rte_experimental
+rte_rawdev_xstats_get(uint16_t dev_id,
+		      const unsigned int ids[],
+		      uint64_t values[],
+		      unsigned int n);
+
+/**
+ * Retrieve the value of a single stat by requesting it by name.
+ *
+ * @param dev_id
+ *   The identifier of the device
+ * @param name
+ *   The stat name to retrieve
+ * @param[out] id
+ *   If non-NULL, the numerical id of the stat will be returned, so that further
+ *   requests for the stat can be got using rte_rawdev_xstats_get, which will
+ *   be faster as it doesn't need to scan a list of names for the stat.
+ *   If the stat cannot be found, the id returned will be (unsigned)-1.
+ * @return
+ *   - positive value or zero: the stat value
+ *   - negative value: -EINVAL if stat not found, -ENOTSUP if not supported.
+ */
+uint64_t __rte_experimental
+rte_rawdev_xstats_by_name_get(uint16_t dev_id,
+			      const char *name,
+			      unsigned int *id);
+
+/**
+ * Reset the values of the xstats of the selected component in the device.
+ *
+ * @param dev_id
+ *   The identifier of the device
+ * @param ids
+ *   Selects specific statistics to be reset. When NULL, all statistics
+ *   will be reset. If non-NULL, must point to array of at least
+ *   *nb_ids* size.
+ * @param nb_ids
+ *   The number of ids available from the *ids* array. Ignored when ids is NULL.
+ * @return
+ *   - zero: successfully reset the statistics to zero
+ *   - negative value: -EINVAL invalid parameters, -ENOTSUP if not supported.
+ */
+int __rte_experimental
+rte_rawdev_xstats_reset(uint16_t dev_id,
+			const uint32_t ids[],
+			uint32_t nb_ids);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/librte_rawdev/rte_rawdev_pmd.h b/lib/librte_rawdev/rte_rawdev_pmd.h
index fe9cc6722..abc7c15c5 100644
--- a/lib/librte_rawdev/rte_rawdev_pmd.h
+++ b/lib/librte_rawdev/rte_rawdev_pmd.h
@@ -353,6 +353,69 @@ typedef int (*rawdev_set_attr_t)(struct rte_rawdev *dev,
 				 const char *attr_name,
 				 const uint64_t attr_value);
 
+/**
+ * Retrieve a set of statistics from device.
+ * Note: Being a raw device, the stats are specific to the device being
+ * implemented thus represented as xstats.
+ *
+ * @param dev
+ *   Raw device pointer
+ * @param ids
+ *   The stat ids to retrieve
+ * @param values
+ *   The returned stat values
+ * @param n
+ *   The number of id values and entries in the values array
+ * @return
+ *   The number of stat values successfully filled into the values array
+ */
+typedef int (*rawdev_xstats_get_t)(const struct rte_rawdev *dev,
+		const unsigned int ids[], uint64_t values[], unsigned int n);
+
+/**
+ * Resets the statistic values in xstats for the device.
+ */
+typedef int (*rawdev_xstats_reset_t)(struct rte_rawdev *dev,
+		const uint32_t ids[],
+		uint32_t nb_ids);
+
+/**
+ * Get names of extended stats of an raw device
+ *
+ * @param dev
+ *   Raw device pointer
+ * @param xstats_names
+ *   Array of name values to be filled in
+ * @param size
+ *   Number of values in the xstats_names array
+ * @return
+ *   When size >= the number of stats, return the number of stat values filled
+ *   into the array.
+ *   When size < the number of available stats, return the number of stats
+ *   values, and do not fill in any data into xstats_names.
+ */
+typedef int (*rawdev_xstats_get_names_t)(const struct rte_rawdev *dev,
+		struct rte_rawdev_xstats_name *xstats_names,
+		unsigned int size);
+
+/**
+ * Get value of one stats and optionally return its id
+ *
+ * @param dev
+ *   Raw device pointer
+ * @param name
+ *   The name of the stat to retrieve
+ * @param id
+ *   Pointer to an unsigned int where we store the stat-id.
+ *   This pointer may be null if the id is not required.
+ * @return
+ *   The value of the stat, or (uint64_t)-1 if the stat is not found.
+ *   If the stat is not found, the id value will be returned as (unsigned)-1,
+ *   if id pointer is non-NULL
+ */
+typedef uint64_t (*rawdev_xstats_get_by_name_t)(const struct rte_rawdev *dev,
+						const char *name,
+						unsigned int *id);
 /** Rawdevice operations function pointer table */
 struct rte_rawdev_ops {
 	/**< Get device info. */
@@ -388,6 +451,15 @@ struct rte_rawdev_ops {
 	rawdev_get_attr_t attr_get;
 	/**< Set an attribute managed by the implementation */
 	rawdev_set_attr_t attr_set;
+
+	/**< Get extended device statistics. */
+	rawdev_xstats_get_t xstats_get;
+	/**< Get names of extended stats. */
+	rawdev_xstats_get_names_t xstats_get_names;
+	/**< Get one value by name. */
+	rawdev_xstats_get_by_name_t xstats_get_by_name;
+	/**< Reset the statistics values in xstats. */
+	rawdev_xstats_reset_t xstats_reset;
 };
 
 /**
diff --git a/lib/librte_rawdev/rte_rawdev_version.map b/lib/librte_rawdev/rte_rawdev_version.map
index bafe2c5de..469b78d81 100644
--- a/lib/librte_rawdev/rte_rawdev_version.map
+++ b/lib/librte_rawdev/rte_rawdev_version.map
@@ -19,6 +19,10 @@ EXPERIMENTAL {
 	rte_rawdev_socket_id;
 	rte_rawdev_start;
 	rte_rawdev_stop;
+	rte_rawdev_xstats_by_name_get;
+	rte_rawdev_xstats_get;
+	rte_rawdev_xstats_names_get;
+	rte_rawdev_xstats_reset;
 	rte_rawdevs;
 
 	local: *;
-- 
2.14.1