eventdev-ethdev connections and ``rte_service_run_state_set()`` to enable the
service function if one exists.
+.. Note::
+
+ The eventdev to which the event_eth_rx_adapter is connected needs to
+ be started before calling rte_event_eth_rx_adapter_start().
+
Getting Adapter Statistics
~~~~~~~~~~~~~~~~~~~~~~~~~~
if the callback is supported, and the counts maintained by the service function,
if one exists. The service function also maintains a count of cycles for which
it was not able to enqueue to the event device.
+
+Interrupt Based Rx Queues
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The service core function is typically set up to poll ethernet Rx queues for
+packets. Certain queues may have low packet rates and it would be more
+efficient to enable the Rx queue interrupt and read packets after receiving
+the interrupt.
+
+The servicing_weight member of struct rte_event_eth_rx_adapter_queue_conf
+is applicable when the adapter uses a service core function. The application
+has to enable Rx queue interrupts when configuring the ethernet device
+using the ``rte_eth_dev_configure()`` function and then use a servicing_weight
+of zero when adding the Rx queue to the adapter.
+
+The adapter creates a thread blocked on the interrupt, on an interrupt this
+thread enqueues the port id and the queue id to a ring buffer. The adapter
+service function dequeues the port id and queue id from the ring buffer,
+invokes the ``rte_eth_rx_burst()`` to receive packets on the queue and
+converts the received packets to events in the same manner as packets
+received on a polled Rx queue. The interrupt thread is affinitized to the same
+CPUs as the lcores of the Rx adapter service function, if the Rx adapter
+service function has not been mapped to any lcores, the interrupt thread
+is mapped to the main lcore.
+
+Rx Callback for SW Rx Adapter
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+For SW based packet transfers, i.e., when the
+``RTE_EVENT_ETH_RX_ADAPTER_CAP_INTERNAL_PORT`` is not set in the adapter's
+capabilities flags for a particular ethernet device, the service function
+temporarily enqueues mbufs to an event buffer before batch enqueuing these
+to the event device. If the buffer fills up, the service function stops
+dequeuing packets from the ethernet device. The application may want to
+monitor the buffer fill level and instruct the service function to selectively
+enqueue packets to the event device. The application may also use some other
+criteria to decide which packets should enter the event device even when
+the event buffer fill level is low. The
+``rte_event_eth_rx_adapter_cb_register()`` function allow the application
+to register a callback that selects which packets to enqueue to the event
+device.
+
+Rx event vectorization
+~~~~~~~~~~~~~~~~~~~~~~
+
+The event devices, ethernet device pairs which support the capability
+``RTE_EVENT_ETH_RX_ADAPTER_CAP_EVENT_VECTOR`` can aggregate packets based on
+flow characteristics and generate a ``rte_event`` containing ``rte_event_vector``
+whose event type is either ``RTE_EVENT_TYPE_ETHDEV_VECTOR`` or
+``RTE_EVENT_TYPE_ETH_RX_ADAPTER_VECTOR``.
+The aggregation size and timeout are configurable at a queue level and the
+maximum, minimum vector sizes and timeouts vary based on the device capability
+and can be queried using ``rte_event_eth_rx_adapter_vector_limits_get``.
+The Rx adapter additionally might include useful data such as ethernet device
+port and queue identifier in the ``rte_event_vector::port`` and
+``rte_event_vector::queue`` and mark ``rte_event_vector::attr_valid`` as true.
+
+A loop processing ``rte_event_vector`` containing mbufs is shown below.
+
+.. code-block:: c
+
+ event = rte_event_dequeue_burst(event_dev, event_port, &event,
+ 1, 0);
+ if (!event)
+ continue;
+
+ switch (ev.event_type) {
+ case RTE_EVENT_TYPE_ETH_RX_ADAPTER_VECTOR:
+ case RTE_EVENT_TYPE_ETHDEV_VECTOR:
+ struct rte_mbufs **mbufs;
+
+ mbufs = (struct rte_mbufs **)ev[i].vec->mbufs;
+ for (i = 0; i < ev.vec->nb_elem; i++) {
+ /* Process each mbuf. */
+ }
+ break;
+ case ...
+ ...
+ }
+
+Rx event vectorization for SW Rx adapter
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+For SW based event vectorization, i.e., when the
+``RTE_EVENT_ETH_RX_ADAPTER_CAP_INTERNAL_PORT`` is not set in the adapter's
+capabilities flags for a particular ethernet device, the service function
+creates a single event vector flow for all the mbufs arriving on the given
+Rx queue.
+The 20-bit event flow identifier is set to 12-bits of Rx queue identifier
+and 8-bits of ethernet device identifier.
+Flow identifier is formatted as follows:
+
+.. code-block:: console
+
+ 19 12,11 0
+ +---------+--------------+
+ | port_id | queue_id |
+ +---------+--------------+
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