int (*port_query_by_name)(const struct dpif *dpif, const char *devname,
struct dpif_port *port);
- /* Returns one greater than the largest port number accepted in flow
- * actions. */
- odp_port_t (*get_max_ports)(const struct dpif *dpif);
-
/* Returns the Netlink PID value to supply in OVS_ACTION_ATTR_USERSPACE
* actions as the OVS_USERSPACE_ATTR_PID attribute's value, for use in
- * flows whose packets arrived on port 'port_no'.
+ * flows whose packets arrived on port 'port_no'. In the case where the
+ * provider allocates multiple Netlink PIDs to a single port, it may use
+ * 'hash' to spread load among them. The caller need not use a particular
+ * hash function; a 5-tuple hash is suitable.
+ *
+ * (The datapath implementation might use some different hash function for
+ * distributing packets received via flow misses among PIDs. This means
+ * that packets received via flow misses might be reordered relative to
+ * packets received via userspace actions. This is not ordinarily a
+ * problem.)
*
* A 'port_no' of UINT32_MAX should be treated as a special case. The
* implementation should return a reserved PID, not allocated to any port,
*
* A dpif provider that doesn't have meaningful Netlink PIDs can use NULL
* for this function. This is equivalent to always returning 0. */
- uint32_t (*port_get_pid)(const struct dpif *dpif, odp_port_t port_no);
+ uint32_t (*port_get_pid)(const struct dpif *dpif, odp_port_t port_no,
+ uint32_t hash);
/* Attempts to begin dumping the ports in a dpif. On success, returns 0
* and initializes '*statep' with any data needed for iteration. On
* packets. */
int (*flow_flush)(struct dpif *dpif);
- /* Attempts to begin dumping the flows in a dpif. On success, returns 0
- * and initializes '*statep' with any data needed for iteration. On
- * failure, returns a positive errno value. */
- int (*flow_dump_start)(const struct dpif *dpif, void **statep);
+ /* Allocates thread-local state for use with the function 'flow_dump_next'.
+ * On return, initializes '*statep' with any private data needed for
+ * iteration. */
+ void (*flow_dump_state_init)(void **statep);
- /* Attempts to retrieve another flow from 'dpif' for 'state', which was
- * initialized by a successful call to the 'flow_dump_start' function for
- * 'dpif'. On success, updates the output parameters as described below
- * and returns 0. Returns EOF if the end of the flow table has been
- * reached, or a positive errno value on error. This function will not be
- * called again once it returns nonzero within a given iteration (but the
- * 'flow_dump_done' function will be called afterward).
+ /* Attempts to begin dumping the flows in a dpif. On success, returns 0
+ * and initializes '*iterp' with any shared data needed for iteration.
+ * On failure, returns a positive errno value. */
+ int (*flow_dump_start)(const struct dpif *dpif, void **iterp);
+
+ /* Attempts to retrieve another flow from 'dpif' for 'iter', using
+ * 'state' for storage. 'iter' must have been initialized by a successful
+ * call to the 'flow_dump_start' function for 'dpif'. 'state' must have
+ * been initialised with a call to the 'flow_dump_state_init' function for
+ * 'dpif.
+ *
+ * On success, updates the output parameters as described below and returns
+ * 0. Returns EOF if the end of the flow table has been reached, or a
+ * positive errno value on error. Multiple threads may use the same 'dpif'
+ * and 'iter' with this function, but all other parameters must be
+ * different for each thread. If this function returns non-zero,
+ * subsequent calls with the same arguments will also return non-zero.
*
* On success:
*
* All of the returned data is owned by 'dpif', not by the caller, and the
* caller must not modify or free it. 'dpif' must guarantee that it
* remains accessible and unchanging until at least the next call to
- * 'flow_dump_next' or 'flow_dump_done' for 'state'. */
- int (*flow_dump_next)(const struct dpif *dpif, void *state,
+ * 'flow_dump_next' or 'flow_dump_done' for 'iter' and 'state'. */
+ int (*flow_dump_next)(const struct dpif *dpif, void *iter, void *state,
const struct nlattr **key, size_t *key_len,
const struct nlattr **mask, size_t *mask_len,
const struct nlattr **actions, size_t *actions_len,
const struct dpif_flow_stats **stats);
- /* Releases resources from 'dpif' for 'state', which was initialized by a
- * successful call to the 'flow_dump_start' function for 'dpif'. */
- int (*flow_dump_done)(const struct dpif *dpif, void *state);
+ /* Determines whether the next call to 'flow_dump_next' with 'state' will
+ * modify or free the keys that it previously returned. 'state' must have
+ * been initialized by a call to 'flow_dump_state_init' for 'dpif'.
+ *
+ * 'dpif' guarantees that data returned by flow_dump_next() will remain
+ * accessible and unchanging until the next call. This function provides a
+ * way for callers to determine whether that guarantee extends beyond the
+ * next call.
+ *
+ * Returns true if the next call to flow_dump_next() is expected to be
+ * destructive to previously returned keys for 'state', false otherwise. */
+ bool (*flow_dump_next_may_destroy_keys)(void *state);
+
+ /* Releases resources from 'dpif' for 'iter', which was initialized by a
+ * successful call to the 'flow_dump_start' function for 'dpif'. Callers
+ * must ensure that this function is called once within a given iteration,
+ * as the final flow dump operation. */
+ int (*flow_dump_done)(const struct dpif *dpif, void *iter);
+
+ /* Releases 'state' which was initialized by a call to the
+ * 'flow_dump_state_init' function for this 'dpif'. */
+ void (*flow_dump_state_uninit)(void *statep);
/* Performs the 'execute->actions_len' bytes of actions in
- * 'execute->actions' on the Ethernet frame specified in 'execute->packet'
- * taken from the flow specified in the 'execute->key_len' bytes of
- * 'execute->key'. ('execute->key' is mostly redundant with
- * 'execute->packet', but it contains some metadata that cannot be
- * recovered from 'execute->packet', such as tunnel and in_port.) */
- int (*execute)(struct dpif *dpif, const struct dpif_execute *execute);
+ * 'execute->actions' on the Ethernet frame in 'execute->packet'
+ * and on the packet metadata in 'execute->md'.
+ * May modify both packet and metadata. */
+ int (*execute)(struct dpif *dpif, struct dpif_execute *execute);
/* Executes each of the 'n_ops' operations in 'ops' on 'dpif', in the order
* in which they are specified, placing each operation's results in the
* updating flows as necessary if it does this. */
int (*recv_set)(struct dpif *dpif, bool enable);
+ /* Refreshes the poll loops and Netlink sockets associated to each port,
+ * when the number of upcall handlers (upcall receiving thread) is changed
+ * to 'n_handlers' and receiving packets for 'dpif' is enabled by
+ * recv_set().
+ *
+ * Since multiple upcall handlers can read upcalls simultaneously from
+ * 'dpif', each port can have multiple Netlink sockets, one per upcall
+ * handler. So, handlers_set() is responsible for the following tasks:
+ *
+ * When receiving upcall is enabled, extends or creates the
+ * configuration to support:
+ *
+ * - 'n_handlers' Netlink sockets for each port.
+ *
+ * - 'n_handlers' poll loops, one for each upcall handler.
+ *
+ * - registering the Netlink sockets for the same upcall handler to
+ * the corresponding poll loop.
+ * */
+ int (*handlers_set)(struct dpif *dpif, uint32_t n_handlers);
+
/* Translates OpenFlow queue ID 'queue_id' (in host byte order) into a
* priority value used for setting packet priority. */
int (*queue_to_priority)(const struct dpif *dpif, uint32_t queue_id,
uint32_t *priority);
- /* Polls for an upcall from 'dpif'. If successful, stores the upcall into
- * '*upcall', using 'buf' for storage. Should only be called if 'recv_set'
- * has been used to enable receiving packets from 'dpif'.
- *
- * The implementation should point 'upcall->packet' and 'upcall->key' into
- * data in the caller-provided 'buf'. If necessary to make room, the
- * implementation may expand the data in 'buf'. (This is hardly a great
- * way to do things but it works out OK for the dpif providers that exist
- * so far.)
+ /* Polls for an upcall from 'dpif' for an upcall handler. Since there
+ * can be multiple poll loops (see ->handlers_set()), 'handler_id' is
+ * needed as index to identify the corresponding poll loop. If
+ * successful, stores the upcall into '*upcall', using 'buf' for
+ * storage. Should only be called if 'recv_set' has been used to enable
+ * receiving packets from 'dpif'.
+ *
+ * The implementation should point 'upcall->key' and 'upcall->userdata'
+ * (if any) into data in the caller-provided 'buf'. The implementation may
+ * also use 'buf' for storing the data of 'upcall->packet'. If necessary
+ * to make room, the implementation may reallocate the data in 'buf'.
+ *
+ * The caller owns the data of 'upcall->packet' and may modify it. If
+ * packet's headroom is exhausted as it is manipulated, 'upcall->packet'
+ * will be reallocated. This requires the data of 'upcall->packet' to be
+ * released with ofpbuf_uninit() before 'upcall' is destroyed. However,
+ * when an error is returned, the 'upcall->packet' may be uninitialized
+ * and should not be released.
*
* This function must not block. If no upcall is pending when it is
* called, it should return EAGAIN without blocking. */
- int (*recv)(struct dpif *dpif, struct dpif_upcall *upcall,
- struct ofpbuf *buf);
-
- /* Arranges for the poll loop to wake up when 'dpif' has a message queued
- * to be received with the recv member function. */
- void (*recv_wait)(struct dpif *dpif);
+ int (*recv)(struct dpif *dpif, uint32_t handler_id,
+ struct dpif_upcall *upcall, struct ofpbuf *buf);
+
+ /* Arranges for the poll loop for an upcall handler to wake up when 'dpif'
+ * has a message queued to be received with the recv member functions.
+ * Since there can be multiple poll loops (see ->handlers_set()),
+ * 'handler_id' is needed as index to identify the corresponding poll loop.
+ * */
+ void (*recv_wait)(struct dpif *dpif, uint32_t handler_id);
/* Throws away any queued upcalls that 'dpif' currently has ready to
* return. */