[RESEND 1/2] ethdev: add new API to get RSS hash algorithm by name

[Jie Hai <haijie1@huawei.com>]

This patch supports conversion from names to hash algorithm
(see RTE_ETH_HASH_FUNCTION_XXX).

Signed-off-by: Jie Hai <haijie1@huawei.com>
Reviewed-by: Huisong Li <lihuisong@huawei.com>
---
 doc/guides/rel_notes/release_24_03.rst |  5 +++++
 lib/ethdev/rte_ethdev.c                | 15 +++++++++++++++
 lib/ethdev/rte_ethdev.h                | 20 ++++++++++++++++++++
 lib/ethdev/version.map                 |  3 +++
 4 files changed, 43 insertions(+)

diff --git a/doc/guides/rel_notes/release_24_03.rst b/doc/guides/rel_notes/release_24_03.rst
index e9c9717706a0..bd84875d4f17 100644
--- a/doc/guides/rel_notes/release_24_03.rst
+++ b/doc/guides/rel_notes/release_24_03.rst
@@ -55,6 +55,11 @@ New Features
      Also, make sure to start the actual text at the margin.
      =======================================================
 
+* **Improved support of RSS hash algorithm.**
+
+  * Added new function ``rte_eth_find_rss_algo`` to get RSS hash
+    algorithm by its name.
+
 
 Removed Items
 -------------
diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index 3858983fcc80..c0398d945502 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -4826,6 +4826,21 @@ rte_eth_dev_rss_algo_name(enum rte_eth_hash_function rss_algo)
 	return name;
 }
 
+int
+rte_eth_find_rss_algo(const char *name, uint32_t *algo)
+{
+	unsigned int i;
+
+	for (i = 0; i < RTE_DIM(rte_eth_dev_rss_algo_names); i++) {
+		if (strcmp(name, rte_eth_dev_rss_algo_names[i].name) == 0) {
+			*algo = rte_eth_dev_rss_algo_names[i].algo;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
 int
 rte_eth_dev_udp_tunnel_port_add(uint16_t port_id,
 				struct rte_eth_udp_tunnel *udp_tunnel)
diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
index 77331ce6525e..3bde5c4c17a6 100644
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -4667,6 +4667,26 @@ __rte_experimental
 const char *
 rte_eth_dev_rss_algo_name(enum rte_eth_hash_function rss_algo);
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change, or be removed, without prior notice.
+ *
+ *  Get RSS hash algorithm by its name.
+ *
+ * @param name
+ *   RSS hash algorithm.
+ *
+ * @param algo
+ *   return the RSS hash algorithm found, @see rte_eth_hash_function.
+ *
+ * @return
+ *   - (0) if successful.
+ *   - (-EINVAL) if not found.
+ */
+__rte_experimental
+int
+rte_eth_find_rss_algo(const char *name, uint32_t *algo);
+
 /**
  * Add UDP tunneling port for a type of tunnel.
  *
diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map
index 5c4917c020dc..a050baab0fe7 100644
--- a/lib/ethdev/version.map
+++ b/lib/ethdev/version.map
@@ -316,6 +316,9 @@ EXPERIMENTAL {
 	rte_eth_recycle_rx_queue_info_get;
 	rte_flow_group_set_miss_actions;
 	rte_flow_calc_table_hash;
+
+	# added in 24.03
+	rte_eth_find_rss_algo;
 };
 
 INTERNAL {
-- 
2.30.0