The current extended ethernet statistics fetching involve doing several
string operations, which causes performance issues if there are lots of
statistics and/or network interfaces. This patch changes the xstats
functions to instead use a numeric identifier rather than a string, and
adds the ability to retrieve identifier-to-string mappings.
Signed-off-by: Remy Horton <remy.horton at intel.com>
---
doc/guides/prog_guide/poll_mode_drv.rst | 25 +++++++--
lib/librte_ether/rte_ethdev.c | 93 ++++++++++++++++++++++++++++++---
lib/librte_ether/rte_ethdev.h | 41 +++++++++++++++
lib/librte_ether/rte_ether_version.map | 6 +++
4 files changed, 153 insertions(+), 12 deletions(-)
diff --git a/doc/guides/prog_guide/poll_mode_drv.rst
b/doc/guides/prog_guide/poll_mode_drv.rst
index 7698692..802fb8f 100644
--- a/doc/guides/prog_guide/poll_mode_drv.rst
+++ b/doc/guides/prog_guide/poll_mode_drv.rst
@@ -299,10 +299,27 @@ Extended Statistics API
~~~~~~~~~~~~~~~~~~~~~~~
The extended statistics API allows each individual PMD to expose a unique set
-of statistics. The client of the API provides an array of
-``struct rte_eth_xstats`` type. Each ``struct rte_eth_xstats`` contains a
-string and value pair. The amount of xstats exposed, and position of the
-statistic in the array must remain constant during runtime.
+of statistics. Accessing these from application programs is done via two
+functions:
+
+* ``rte_eth_xstats_get``: Fills in an array of ``struct rte_eth_xstat``
+ with extended statistics.
+* ``rte_eth_xstats_get_names``: Fills in an array of
+ ``struct rte_eth_xstat_name`` with extended statistic name lookup
+ information.
+
+Each ``struct rte_eth_xstat`` contains an identifier and value pair, and
+each ``struct rte_eth_xstat_name`` contains an identifier and string pair.
+Each identifier within ``struct rte_eth_xstat`` must have a corresponding
+entry in ``struct rte_eth_xstat_name`` with a matching identifier. These
+identifiers, as well as the number of extended statistic exposed, must
+remain constant during runtime.
+
+Note that extended statistic identifiers are driver-specific, and hence
+might not be the same for different ports. Although it is expected that
+drivers will make the identifiers used within ``struct rte_eth_xstat`` and
+``struct rte_eth_xstat_name`` entries match the entries' array index, this
+property should not be relied on by applications for lookups.
A naming scheme exists for the strings exposed to clients of the API. This is
to allow scraping of the API for statistics of interest. The naming scheme uses
diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index e148028..98e5efb 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -1502,6 +1502,85 @@ rte_eth_stats_reset(uint8_t port_id)
dev->data->rx_mbuf_alloc_failed = 0;
}
+static int
+get_xstats_count(uint8_t port_id)
+{
+ struct rte_eth_dev *dev;
+ int count;
+
+ RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
+ dev = &rte_eth_devices[port_id];
+ if (dev->dev_ops->xstats_get_names != NULL) {
+ count = (*dev->dev_ops->xstats_get_names)(dev, NULL, 0);
+ if (count < 0)
+ return count;
+ } else
+ count = 0;
+ count += RTE_NB_STATS;
+ count += dev->data->nb_rx_queues * RTE_NB_RXQ_STATS;
+ count += dev->data->nb_tx_queues * RTE_NB_TXQ_STATS;
+ return count;
+}
+
+int
+rte_eth_xstats_get_names(uint8_t port_id,
+ struct rte_eth_xstat_name *xstats_names,
+ unsigned size)
+{
+ struct rte_eth_dev *dev;
+ int cnt_used_entries;
+ int cnt_expected_entries;
+ uint32_t idx, id_queue;
+
+ cnt_expected_entries = get_xstats_count(port_id);
+ if (xstats_names == NULL || cnt_expected_entries < 0 ||
+ (int)size < cnt_expected_entries)
+ return cnt_expected_entries;
+
+ /* port_id checked in get_xstats_count() */
+ dev = &rte_eth_devices[port_id];
+ if (dev->dev_ops->xstats_get_names != NULL) {
+ cnt_used_entries = (*dev->dev_ops->xstats_get_names)(
+ dev, xstats_names, size);
+ if (cnt_used_entries < 0)
+ return cnt_used_entries;
+ } else
+ /* Driver itself does not support extended stats, but
+ * still have basic stats.
+ */
+ cnt_used_entries = 0;
+
+ for (idx = 0; idx < RTE_NB_STATS; idx++) {
+ xstats_names[cnt_used_entries].id = cnt_used_entries;
+ snprintf(xstats_names[cnt_used_entries].name,
+ sizeof(xstats_names[0].name),
+ "%s", rte_stats_strings[idx].name);
+ cnt_used_entries++;
+ }
+ for (id_queue = 0; id_queue < dev->data->nb_rx_queues; id_queue++) {
+ for (idx = 0; idx < RTE_NB_RXQ_STATS; idx++) {
+ xstats_names[cnt_used_entries].id = cnt_used_entries;
+ snprintf(xstats_names[cnt_used_entries].name,
+ sizeof(xstats_names[0].name),
+ "rx_q%u%s",
+ id_queue, rte_rxq_stats_strings[idx].name);
+ cnt_used_entries++;
+ }
+
+ }
+ for (id_queue = 0; id_queue < dev->data->nb_tx_queues; id_queue++) {
+ for (idx = 0; idx < RTE_NB_TXQ_STATS; idx++) {
+ xstats_names[cnt_used_entries].id = cnt_used_entries;
+ snprintf(xstats_names[cnt_used_entries].name,
+ sizeof(xstats_names[0].name),
+ "tx_q%u%s",
+ id_queue, rte_txq_stats_strings[idx].name);
+ cnt_used_entries++;
+ }
+ }
+ return cnt_used_entries;
+}
+
/* retrieve ethdev extended statistics */
int
rte_eth_xstats_get(uint8_t port_id, struct rte_eth_xstats *xstats,
@@ -1546,8 +1625,8 @@ rte_eth_xstats_get(uint8_t port_id, struct rte_eth_xstats
*xstats,
stats_ptr = RTE_PTR_ADD(ð_stats,
rte_stats_strings[i].offset);
val = *stats_ptr;
- snprintf(xstats[count].name, sizeof(xstats[count].name),
- "%s", rte_stats_strings[i].name);
+ xstats[count].name[0] = '\0';
+ xstats[count].id = count + xcount;
xstats[count++].value = val;
}
@@ -1558,9 +1637,8 @@ rte_eth_xstats_get(uint8_t port_id, struct rte_eth_xstats
*xstats,
rte_rxq_stats_strings[i].offset +
q * sizeof(uint64_t));
val = *stats_ptr;
- snprintf(xstats[count].name, sizeof(xstats[count].name),
- "rx_q%u_%s", q,
- rte_rxq_stats_strings[i].name);
+ xstats[count].name[0] = '\0';
+ xstats[count].id = count + xcount;
xstats[count++].value = val;
}
}
@@ -1572,9 +1650,8 @@ rte_eth_xstats_get(uint8_t port_id, struct rte_eth_xstats
*xstats,
rte_txq_stats_strings[i].offset +
q * sizeof(uint64_t));
val = *stats_ptr;
- snprintf(xstats[count].name, sizeof(xstats[count].name),
- "tx_q%u_%s", q,
- rte_txq_stats_strings[i].name);
+ xstats[count].name[0] = '\0';
+ xstats[count].id = count + xcount;
xstats[count++].value = val;
}
}
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index 2757510..5de86b8 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -916,9 +916,21 @@ struct rte_eth_txq_info {
*/
struct rte_eth_xstats {
char name[RTE_ETH_XSTATS_NAME_SIZE];
+ uint64_t id;
uint64_t value;
};
+/**
+ * A name-key lookup element for extended statistics.
+ *
+ * This structure is used to map between names and ID numbers
+ * for extended ethernet statistics.
+ */
+struct rte_eth_xstat_name {
+ char name[RTE_ETH_XSTATS_NAME_SIZE];
+ uint64_t id;
+};
+
#define ETH_DCB_NUM_TCS 8
#define ETH_MAX_VMDQ_POOL 64
@@ -1054,6 +1066,10 @@ typedef int (*eth_xstats_get_t)(struct rte_eth_dev *dev,
typedef void (*eth_xstats_reset_t)(struct rte_eth_dev *dev);
/**< @internal Reset extended stats of an Ethernet device. */
+typedef int (*eth_xstats_get_names_t)(struct rte_eth_dev *dev,
+ struct rte_eth_xstat_name *xstats_names, unsigned size);
+/**< @internal Get names of extended stats of an Ethernet device. */
+
typedef int (*eth_queue_stats_mapping_set_t)(struct rte_eth_dev *dev,
uint16_t queue_id,
uint8_t stat_idx,
@@ -1401,6 +1417,8 @@ struct eth_dev_ops {
eth_stats_reset_t stats_reset; /**< Reset generic device
statistics. */
eth_xstats_get_t xstats_get; /**< Get extended device
statistics. */
eth_xstats_reset_t xstats_reset; /**< Reset extended device
statistics. */
+ eth_xstats_get_names_t xstats_get_names;
+ /**< Get names of extended statistics. */
eth_queue_stats_mapping_set_t queue_stats_mapping_set;
/**< Configure per queue stat counter mapping. */
eth_dev_infos_get_t dev_infos_get; /**< Get device info. */
@@ -2253,6 +2271,29 @@ int rte_eth_stats_get(uint8_t port_id, struct
rte_eth_stats *stats);
void rte_eth_stats_reset(uint8_t port_id);
/**
+ * Retrieve names of extended statistics of an Ethernet device.
+ *
+ * @param port_id
+ * The port identifier of the Ethernet device.
+ * @param 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 (invalid port id)
+ */
+int rte_eth_xstats_get_names(uint8_t port_id,
+ struct rte_eth_xstat_name *xstats_names,
+ unsigned size);
+
+/**
* Retrieve extended statistics of an Ethernet device.
*
* @param port_id
diff --git a/lib/librte_ether/rte_ether_version.map
b/lib/librte_ether/rte_ether_version.map
index 214ecc7..722b4d6 100644
--- a/lib/librte_ether/rte_ether_version.map
+++ b/lib/librte_ether/rte_ether_version.map
@@ -132,3 +132,9 @@ DPDK_16.04 {
rte_eth_tx_buffer_set_err_callback;
} DPDK_2.2;
+
+DPDK_16.07 {
+ global:
+
+ rte_eth_xstats_get_names;
+} DPDK_16.04;
--
2.5.5
