eventdev: add support for independent enqueue

Support for independent enqueue feature and updates Event Device
and PMD feature list.

A new capability RTE_EVENT_DEV_CAP_INDEPENDENT_ENQ is introduced. It
allows out-of-order enqueuing of RTE_EVENT_OP_FORWARD or RELEASE type
events on an event port where this capability is enabled.

To use this capability applications need to set flag
RTE_EVENT_PORT_CFG_INDEPENDENT_ENQ during port setup only if the
capability RTE_EVENT_DEV_CAP_INDEPENDENT_ENQ exists.

Signed-off-by: Abdullah Sevincer <[email protected]>
Acked-by: Mattias Rönnblom <[email protected]>
Acked-by: Jerin Jacob <[email protected]>

Author: asevince

doc/guides/eventdevs/features/default.ini

@@ -22,6 +22,7 @@ carry_flow_id              =
 maintenance_free           =
 runtime_queue_attr         =
 profile_links              =
+independent_enq            =
 
 ;
 ; Features of a default Ethernet Rx adapter.

doc/guides/prog_guide/eventdev/eventdev.rst

@@ -472,6 +472,29 @@ A flush callback can be passed to the function to handle any outstanding events.
 
         Invocation of this API does not affect the existing port configuration.
 
+Independent Enqueue Capability
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This capability applies to eventdev devices that expects all forwarded events to be
+enqueued in the same order as they are dequeued. For dropped events, their
+releases should come at the same location as the original event was expected.
+The eventdev device has this restriction as it uses the order to retrieve information about
+the original event that was sent to the CPU. This contains information like atomic
+flow ID to release the flow lock and ordered events sequence number to restore the
+original order.
+
+This capability only matters to eventdevs supporting burst mode. On ports where
+the application is going to change enqueue order,
+``RTE_EVENT_PORT_CFG_INDEPENDENT_ENQ`` support should be enabled.
+
+Example code to inform PMD that the application plans to use independent enqueue
+order on a port:
+
+    .. code-block:: c
+
+       if (capability & RTE_EVENT_DEV_CAP_INDEPENDENT_ENQ)
+         port_config = port_config | RTE_EVENT_PORT_CFG_INDEPENDENT_ENQ;
+
 Stopping the EventDev
 ~~~~~~~~~~~~~~~~~~~~~
 

doc/guides/rel_notes/release_24_11.rst

@@ -67,6 +67,14 @@ New Features
 
   The new statistics are useful for debugging and profiling.
 
+* **Updated Event Device Library for independent enqueue feature**
+
+  * Added support for independent enqueue feature. With this feature Eventdev
+    supports enqueue in any order or specifically in a different order than
+    dequeue. The feature is intended for eventdevs supporting burst mode.
+    Applications should  use ``RTE_EVENT_PORT_CFG_INDEPENDENT_ENQ`` to enable
+    the feature if the capability  ``RTE_EVENT_DEV_CAP_INDEPENDENT_ENQ`` exists.
+
 
 Removed Items
 -------------

lib/eventdev/rte_eventdev.h

@@ -446,6 +446,25 @@ struct rte_event;
  * @see RTE_SCHED_TYPE_PARALLEL
  */
 
+#define RTE_EVENT_DEV_CAP_INDEPENDENT_ENQ  (1ULL << 16)
+/**< Event device is capable of independent enqueue.
+ * A new capability, RTE_EVENT_DEV_CAP_INDEPENDENT_ENQ, will indicate that Eventdev
+ * supports the enqueue in any order or specifically in a different order than the
+ * dequeue. Eventdev PMD can either dequeue events in the changed order in which
+ * they are enqueued or restore the original order before sending them to the
+ * underlying hardware device. A flag is provided during the port configuration to
+ * inform Eventdev PMD that the application intends to use an independent enqueue
+ * order on a particular port. Note that this capability only matters for eventdevs
+ * supporting burst mode.
+ *
+ * When an implicit release is enabled on a port, Eventdev PMD will also handle
+ * the insertion of RELEASE events in place of dropped events. The independent enqueue
+ * feature only applies to FORWARD and RELEASE events. New events (op=RTE_EVENT_OP_NEW)
+ * will be dequeued in the order the application enqueues them and do not maintain
+ * any order relative to FORWARD/RELEASE events. FORWARD vs NEW relaxed ordering
+ * only applies to ports that have enabled independent enqueue feature.
+ */
+
 /* Event device priority levels */
 #define RTE_EVENT_DEV_PRIORITY_HIGHEST   0
 /**< Highest priority level for events and queues.
@@ -1072,6 +1091,18 @@ rte_event_queue_attr_set(uint8_t dev_id, uint8_t queue_id, uint32_t attr_id,
  *
  *  @see rte_event_port_setup()
  */
+#define RTE_EVENT_PORT_CFG_INDEPENDENT_ENQ   (1ULL << 5)
+/**< Flag to enable independent enqueue. Must not be set if the device
+ * is not RTE_EVENT_DEV_CAP_INDEPENDENT_ENQ capable. This feature
+ * allows an application to enqueue RTE_EVENT_OP_FORWARD or
+ * RTE_EVENT_OP_RELEASE in an order different than the order the
+ * events were dequeued from the event device, while maintaining
+ * RTE_SCHED_TYPE_ATOMIC or RTE_SCHED_TYPE_ORDERED semantics.
+ *
+ * Note that this flag only matters for Eventdevs supporting burst mode.
+ *
+ *  @see rte_event_port_setup()
+ */
 
 /** Event port configuration structure */
 struct rte_event_port_conf {