From: Ivan Ilchenko <ivan.ilche...@oktetlabs.ru>
Document valid combinations of input arguments in accordance with
current implementation in ethdev.
Fixes: 79c913a42f0 ("ethdev: retrieve xstats by ID")
Cc: sta...@dpdk.org
Signed-off-by: Ivan Ilchenko <ivan.ilche...@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <andrew.rybche...@oktetlabs.ru>
Reviewed-by: Andy Moreton <amore...@xilinx.com>
---
lib/ethdev/rte_ethdev.h | 23 ++++++++++++++---------
1 file changed, 14 insertions(+), 9 deletions(-)
diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
index d2b27c351f..28440c46d3 100644
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -2873,12 +2873,15 @@ int rte_eth_xstats_get(uint16_t port_id, struct
rte_eth_xstat *xstats,
* The port identifier of the Ethernet device.
* @param xstats_names
* An rte_eth_xstat_name array of at least *size* elements to
- * be filled. If set to NULL, the function returns the required number
- * of elements.
+ * be filled. Must not be NULL if @p ids are specified (not NULL).
* @param ids
- * IDs array given by app to retrieve specific statistics
+ * IDs array given by app to retrieve specific statistics. May be NULL
+ * to retrieve all available statistics.
* @param size
- * The size of the xstats_names array (number of elements).
+ * If @p ids is not NULL, number of elements in the array with requested IDs
+ * and number of elements in @p xstats_names to put names in. If @p ids is
+ * NULL, number of elements in @p xstats_names to put all available
statistics
+ * names in.
* @return
* - A positive value lower or equal to size: success. The return value
* is the number of entries filled in the stats table.
@@ -2886,7 +2889,7 @@ int rte_eth_xstats_get(uint16_t port_id, struct
rte_eth_xstat *xstats,
* 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.
- * - A negative value on error (invalid port id).
+ * - A negative value on error.
*/
int
rte_eth_xstats_get_names_by_id(uint16_t port_id,
@@ -2900,13 +2903,15 @@ rte_eth_xstats_get_names_by_id(uint16_t port_id,
* The port identifier of the Ethernet device.
* @param ids
* A pointer to an ids array passed by application. This tells which
- * statistics values function should retrieve. This parameter
- * can be set to NULL if size is 0. In this case function will retrieve
+ * statistics values function should retrieve. May be NULL to retrieve
* all available statistics.
* @param values
* A pointer to a table to be filled with device statistics values.
+ * Must not be NULL if ids are specified (not NULL).
* @param size
- * The size of the ids array (number of elements).
+ * If @p ids is not NULL, number of elements in the array with requested IDs
+ * and number of elements in values to put statistics in. If @p ids is NULL,
+ * number of elements in values to put all available statistics in.
* @return
* - A positive value lower or equal to size: success. The return value
* is the number of entries filled in the stats table.
@@ -2914,7 +2919,7 @@ rte_eth_xstats_get_names_by_id(uint16_t port_id,
* 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.
- * - A negative value on error (invalid port id).
+ * - A negative value on error.
*/
int rte_eth_xstats_get_by_id(uint16_t port_id, const uint64_t *ids,
uint64_t *values, unsigned int size);
--
2.30.2
