- * callback can use these values to decide which mbufs should be
- * enqueued to the event device. If the return value of the callback
- * is less than nb_mbuf then the SW adapter uses the return value to
- * enqueue enq_mbuf[] to the event device.
+ * callback can use these values to decide which events are
+ * enqueued to the event device by the SW adapter. The callback may
+ * also enqueue events internally using its own event port. The SW
+ * adapter populates the event information based on the Rx queue
+ * configuration in the adapter. The callback can modify the this event
+ * information for the events to be enqueued by the SW adapter.
+ *
+ * The callback return value is the number of events from the
+ * beginning of the event array that are to be enqueued by
+ * the SW adapter. It is the callback's responsibility to arrange
+ * these events at the beginning of the array, if these events are
+ * not contiguous in the original array. The *nb_dropped* parameter is
+ * a pointer to the number of events dropped by the callback, this
+ * number is used by the adapter to indicate the number of dropped packets
+ * as part of its statistics.