[RFC] ethdev: add group set miss actions API

[Tomer Shmilovich <tshmilovich@nvidia.com>]

Introduce new group set miss actions API:
rte_flow_group_set_miss_actions().

A group's miss actions are a set of actions to be performed
in case of a miss on a group, i.e. when a packet didn't hit any flow
rules in the group.

Currently, the expected behavior in this case is undefined.
In order to achieve such functionality, a user can add a flow rule
that matches on all traffic with the lowest priority in the group -
this is not explicit however, and can be overridden by another flow rule
with a lower priority.

This new API function allows a user to set a group's miss actions in an
explicit way.

Signed-off-by: Tomer Shmilovich <tshmilovich@nvidia.com>
---
 doc/guides/prog_guide/rte_flow.rst | 30 +++++++++++++++++++++++++
 lib/ethdev/rte_flow.c              | 22 +++++++++++++++++++
 lib/ethdev/rte_flow.h              | 35 ++++++++++++++++++++++++++++++
 lib/ethdev/rte_flow_driver.h       |  7 ++++++
 lib/ethdev/version.map             |  3 +++
 5 files changed, 97 insertions(+)

diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
index 5bc998a433..590d2a770e 100644
--- a/doc/guides/prog_guide/rte_flow.rst
+++ b/doc/guides/prog_guide/rte_flow.rst
@@ -3758,6 +3758,36 @@ Information about the number of available resources can be retrieved via
                      struct rte_flow_queue_info *queue_info,
                      struct rte_flow_error *error);
 
+Group Miss Actions
+~~~~~~~~~~~~~~~~~~
+
+In an application, many flow rules share common group attributes, meaning they can be grouped and
+classified together. A user can explicitly specify a set of actions performed on a packet when it
+did not match any flows rules in a group using the following API:
+
+.. code-block:: c
+
+      int
+      rte_flow_group_set_miss_actions(uint16_t port_id,
+                                      uint32_t group_id,
+                                      const struct rte_flow_group_attr *attr,
+                                      const struct rte_flow_action actions[],
+                                      struct rte_flow_error *error);
+
+For example, to configure a RTE_FLOW_TYPE_JUMP action as a miss action for ingress group 1:
+
+.. code-block:: c
+
+      struct rte_flow_group_attr attr = {.ingress = 1};
+      struct rte_flow_action act[] = {
+      /* Setting miss actions to jump to group 3 */
+          [0] = {.type = RTE_FLOW_ACTION_TYPE_JUMP,
+                 .conf = &(struct rte_flow_action_jump){.group = 3}},
+          [1] = {.type = RTE_FLOW_ACTION_TYPE_END},
+      };
+      struct rte_flow_error err;
+      rte_flow_group_set_miss_actions(port, 1, &attr, act, &err);
+
 Flow templates
 ~~~~~~~~~~~~~~
 
diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c
index 271d854f78..a98d87265f 100644
--- a/lib/ethdev/rte_flow.c
+++ b/lib/ethdev/rte_flow.c
@@ -1973,6 +1973,28 @@ rte_flow_template_table_destroy(uint16_t port_id,
 				  NULL, rte_strerror(ENOTSUP));
 }
 
+int
+rte_flow_group_set_miss_actions(uint16_t port_id,
+				uint32_t group_id,
+				const struct rte_flow_group_attr *attr,
+				const struct rte_flow_action actions[],
+				struct rte_flow_error *error)
+{
+	struct rte_eth_dev *dev = &rte_eth_devices[port_id];
+	const struct rte_flow_ops *ops = rte_flow_ops_get(port_id, error);
+
+	if (unlikely(!ops))
+		return -rte_errno;
+	if (likely(!!ops->group_set_miss_actions)) {
+		return flow_err(port_id,
+				ops->group_set_miss_actions(dev, group_id, attr, actions, error),
+				error);
+	}
+	return rte_flow_error_set(error, ENOTSUP,
+				  RTE_FLOW_ERROR_TYPE_UNSPECIFIED,
+				  NULL, rte_strerror(ENOTSUP));
+}
+
 struct rte_flow *
 rte_flow_async_create(uint16_t port_id,
 		      uint32_t queue_id,
diff --git a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h
index 86ed98c562..2d4fd49eb7 100644
--- a/lib/ethdev/rte_flow.h
+++ b/lib/ethdev/rte_flow.h
@@ -129,6 +129,12 @@ struct rte_flow_attr {
 	uint32_t reserved:29; /**< Reserved, must be zero. */
 };
 
+struct rte_flow_group_attr {
+	uint32_t ingress:1;
+	uint32_t egress:1;
+	uint32_t transfer:1;
+};
+
 /**
  * Matching pattern item types.
  *
@@ -5839,6 +5845,35 @@ rte_flow_template_table_destroy(uint16_t port_id,
 		struct rte_flow_template_table *template_table,
 		struct rte_flow_error *error);
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Set group miss actions.
+ *
+ * @param port_id
+ *   Port identifier of Ethernet device.
+ * @param group_id
+ *   Identifier of a group to set miss actions for.
+ * @param attr
+ *   Group attributes.
+ * @param actions
+ *   List of group miss actions.
+ * @param[out] error
+ *   Perform verbose error reporting if not NULL.
+ *   PMDs initialize this structure in case of error only.
+ *
+ * @return
+ *   0 on success, a negative errno value otherwise and rte_errno is set.
+ */
+__rte_experimental
+int
+rte_flow_group_set_miss_actions(uint16_t port_id,
+				uint32_t group_id,
+				const struct rte_flow_group_attr *attr,
+				const struct rte_flow_action actions[],
+				struct rte_flow_error *error);
+
 /**
  * @warning
  * @b EXPERIMENTAL: this API may change without prior notice.
diff --git a/lib/ethdev/rte_flow_driver.h b/lib/ethdev/rte_flow_driver.h
index f9fb01b8a2..3ced086c47 100644
--- a/lib/ethdev/rte_flow_driver.h
+++ b/lib/ethdev/rte_flow_driver.h
@@ -227,6 +227,13 @@ struct rte_flow_ops {
 		(struct rte_eth_dev *dev,
 		 struct rte_flow_template_table *template_table,
 		 struct rte_flow_error *err);
+	/** See rte_flow_group_set_miss_actions() */
+	int (*group_set_miss_actions)
+		(struct rte_eth_dev *dev,
+		 uint32_t group_id,
+		 const struct rte_flow_group_attr *attr,
+		 const struct rte_flow_action actions[],
+		 struct rte_flow_error *err);
 	/** See rte_flow_async_create() */
 	struct rte_flow *(*async_create)
 		(struct rte_eth_dev *dev,
diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map
index fc492ee839..bdd41ecb5e 100644
--- a/lib/ethdev/version.map
+++ b/lib/ethdev/version.map
@@ -312,6 +312,9 @@ EXPERIMENTAL {
 	rte_flow_async_action_list_handle_query_update;
 	rte_flow_async_actions_update;
 	rte_flow_restore_info_dynflag;
+
+	# added in 23.11
+	rte_flow_group_set_miss_actions;
 };
 
 INTERNAL {
-- 
2.34.1