-/*
- * Recirculation
- * =============
- *
- * Recirculation is a technique to allow a frame to re-enter the packet
- * processing path for one or multiple times to achieve more flexible packet
- * processing in the data path. MPLS handling and selecting bond slave port
- * of a bond ports.
- *
- * Data path and user space interface
- * -----------------------------------
- *
- * Two new fields, recirc_id and dp_hash, are added to the current flow data
- * structure. They are both of type uint32_t. In addition, a new action,
- * RECIRC, are added.
- *
- * The value recirc_id is used to distinguish a packet from multiple
- * iterations of recirculation. A packet initially received is considered of
- * having recirc_id of 0. Recirc_id is managed by the user space, opaque to
- * the data path.
- *
- * On the other hand, dp_hash can only be computed by the data path, opaque to
- * the user space. In fact, user space may not able to recompute the hash
- * value. The dp_hash value should be wildcarded when for a newly received
- * packet. RECIRC action specifies whether the hash is computed. If computed,
- * how many fields to be included in the hash computation. The computed hash
- * value is stored into the dp_hash field prior to recirculation.
- *
- * The RECIRC action computes and set the dp_hash field, set the recirc_id
- * field and then reprocess the packet as if it was received on the same input
- * port. RECIRC action works like a function call; actions listed behind the
- * RECIRC action will be executed after its execution. RECIRC action can be
- * nested, data path implementation limits the number of recirculation executed
- * to prevent unreasonable nesting depth or infinite loop.
- *
- * Both flow fields and the RECIRC action are exposed as open flow fields via
- * Nicira extensions.
- *
- * Post recirculation flow
- * ------------------------
- *
- * At the open flow level, post recirculation rules are always hidden from the
- * controller. They are installed in table 254 which is set up as a hidden
- * table during boot time. Those rules are managed by the local user space
- * program only.
- *
- * To speed up the classifier look up process, recirc_id is always reflected
- * into the metadata field, since recirc_id is required to be exactly matched.
- *
- * Classifier look up always starts with table 254. A post recirculation flow
- * lookup should find its hidden rule within this table. On the other hand, A
- * newly received packet should miss all post recirculation rules because its
- * recirc_id is zero, then hit a pre-installed lower priority rule to redirect
- * classifier to look up starting from table 0:
- *
- * * , actions=resubmit(,0)
- *
- * Post recirculation data path flows are managed like other data path flows.
- * They are created on demand. Miss handling, stats collection and revalidation
- * work the same way as regular flows.
- */