/*
- * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* "internal" (for a simulated port used to connect to the TCP/IP stack),
* and "gre" (for a GRE tunnel).
*
- * - A Netlink PID (see "Upcall Queuing and Ordering" below).
+ * - A Netlink PID for each upcall reading thread (see "Upcall Queuing and
+ * Ordering" below).
*
* The dpif interface has functions for adding and deleting ports. When a
* datapath implements these (e.g. as the Linux and netdev datapaths do), then
* connection consists of two flows with 1-ms latency to set up each one.
*
* To receive upcalls, a client has to enable them with dpif_recv_set(). A
- * datapath should generally support multiple clients at once (e.g. so that one
- * may run "ovs-dpctl show" or "ovs-dpctl dump-flows" while "ovs-vswitchd" is
- * also running) but need not support multiple clients enabling upcalls at
- * once.
+ * datapath should generally support being opened multiple times (e.g. so that
+ * one may run "ovs-dpctl show" or "ovs-dpctl dump-flows" while "ovs-vswitchd"
+ * is also running) but need not support more than one of these clients
+ * enabling upcalls at once.
*
*
* Upcall Queuing and Ordering
* PID in "action" upcalls is that dpif_port_get_pid() returns a constant value
* and all upcalls are appended to a single queue.
*
- * The ideal behavior is:
+ * The preferred behavior is:
*
* - Each port has a PID that identifies the queue used for "miss" upcalls
* on that port. (Thus, if each port has its own queue for "miss"
*
* - Upcalls that specify the "special" Netlink PID are queued separately.
*
+ * Multiple threads may want to read upcalls simultaneously from a single
+ * datapath. To support multiple threads well, one extends the above preferred
+ * behavior:
+ *
+ * - Each port has multiple PIDs. The datapath distributes "miss" upcalls
+ * across the PIDs, ensuring that a given flow is mapped in a stable way
+ * to a single PID.
+ *
+ * - For "action" upcalls, the thread can specify its own Netlink PID or
+ * other threads' Netlink PID of the same port for offloading purpose
+ * (e.g. in a "round robin" manner).
+ *
*
* Packet Format
* =============
* thread-safe: they may be called from different threads only on
* different dpif objects.
*
- * - Functions that operate on struct dpif_port_dump or struct
- * dpif_flow_dump are conditionally thread-safe with respect to those
- * objects. That is, one may dump ports or flows from any number of
- * threads at once, but each thread must use its own struct dpif_port_dump
- * or dpif_flow_dump.
+ * - dpif_flow_dump_next() is conditionally thread-safe: It may be called
+ * from different threads with the same 'struct dpif_flow_dump', but all
+ * other parameters must be different for each thread.
+ *
+ * - dpif_flow_dump_done() is conditionally thread-safe: All threads that
+ * share the same 'struct dpif_flow_dump' must have finished using it.
+ * This function must then be called exactly once for a particular
+ * dpif_flow_dump to finish the corresponding flow dump operation.
+ *
+ * - Functions that operate on 'struct dpif_port_dump' are conditionally
+ * thread-safe with respect to those objects. That is, one may dump ports
+ * from any number of threads at once, but each thread must use its own
+ * struct dpif_port_dump.
*/
#ifndef DPIF_H
#define DPIF_H 1
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
+#include "netdev.h"
#include "ofpbuf.h"
#include "openflow/openflow.h"
-#include "netdev.h"
+#include "packets.h"
#include "util.h"
#ifdef __cplusplus
uint64_t n_missed; /* Number of flow table misses. */
uint64_t n_lost; /* Number of misses not sent to userspace. */
uint64_t n_flows; /* Number of flows present. */
- uint64_t n_masks; /* Number of mega flow masks. */
uint64_t n_mask_hit; /* Number of mega flow masks visited for
flow table matches. */
+ uint32_t n_masks; /* Number of mega flow masks. */
};
int dpif_get_dp_stats(const struct dpif *, struct dpif_dp_stats *);
struct dpif_port *);
int dpif_port_get_name(struct dpif *, odp_port_t port_no,
char *name, size_t name_size);
-uint32_t dpif_port_get_pid(const struct dpif *, odp_port_t port_no);
+uint32_t dpif_port_get_pid(const struct dpif *, odp_port_t port_no,
+ uint32_t hash);
struct dpif_port_dump {
const struct dpif *dpif;
int dpif_flow_get(const struct dpif *,
const struct nlattr *key, size_t key_len,
struct ofpbuf **actionsp, struct dpif_flow_stats *);
-
-struct dpif_flow_dump {
- const struct dpif *dpif;
- int error;
- void *state;
-};
-void dpif_flow_dump_start(struct dpif_flow_dump *, const struct dpif *);
-bool dpif_flow_dump_next(struct dpif_flow_dump *,
- 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 **);
-int dpif_flow_dump_done(struct dpif_flow_dump *);
\f
-/* Packet operations. */
-
-int dpif_execute(struct dpif *,
- const struct nlattr *key, size_t key_len,
- const struct nlattr *actions, size_t actions_len,
- struct ofpbuf *, bool needs_help);
+/* Flow dumping interface
+ * ======================
+ *
+ * This interface allows iteration through all of the flows currently installed
+ * in a datapath. It is somewhat complicated by two requirements:
+ *
+ * - Efficient support for dumping flows in parallel from multiple threads.
+ *
+ * - Allow callers to avoid making unnecessary copies of data returned by
+ * the interface across several flows in cases where the dpif
+ * implementation has to maintain a copy of that information anyhow.
+ * (That is, allow the client visibility into any underlying batching as
+ * part of its own batching.)
+ *
+ *
+ * Usage
+ * -----
+ *
+ * 1. Call dpif_flow_dump_create().
+ * 2. In each thread that participates in the dump (which may be just a single
+ * thread if parallelism isn't important):
+ * (a) Call dpif_flow_dump_thread_create().
+ * (b) Call dpif_flow_dump_next() repeatedly until it returns 0.
+ * (c) Call dpif_flow_dump_thread_destroy().
+ * 3. Call dpif_flow_dump_destroy().
+ *
+ * All error reporting is deferred to the call to dpif_flow_dump_destroy().
+ */
+struct dpif_flow_dump *dpif_flow_dump_create(const struct dpif *);
+int dpif_flow_dump_destroy(struct dpif_flow_dump *);
+
+struct dpif_flow_dump_thread *dpif_flow_dump_thread_create(
+ struct dpif_flow_dump *);
+void dpif_flow_dump_thread_destroy(struct dpif_flow_dump_thread *);
+
+/* A datapath flow as dumped by dpif_flow_dump_next(). */
+struct dpif_flow {
+ const struct nlattr *key; /* Flow key, as OVS_KEY_ATTR_* attrs. */
+ size_t key_len; /* 'key' length in bytes. */
+ const struct nlattr *mask; /* Flow mask, as OVS_KEY_ATTR_* attrs. */
+ size_t mask_len; /* 'mask' length in bytes. */
+ const struct nlattr *actions; /* Actions, as OVS_ACTION_ATTR_ */
+ size_t actions_len; /* 'actions' length in bytes. */
+ struct dpif_flow_stats stats; /* Flow statistics. */
+};
+int dpif_flow_dump_next(struct dpif_flow_dump_thread *,
+ struct dpif_flow *flows, int max_flows);
\f
/* Operation batching interface.
*
struct dpif_execute {
/* Raw support for execute passed along to the provider. */
- const struct nlattr *key; /* Partial flow key (only for metadata). */
- size_t key_len; /* Length of 'key' in bytes. */
const struct nlattr *actions; /* Actions to execute on packet. */
size_t actions_len; /* Length of 'actions' in bytes. */
struct ofpbuf *packet; /* Packet to execute. */
+ struct pkt_metadata md; /* Packet metadata. */
/* Some dpif providers do not implement every action. The Linux kernel
* datapath, in particular, does not implement ARP field modification.
bool needs_help;
};
+int dpif_execute(struct dpif *, struct dpif_execute *);
+
struct dpif_op {
enum dpif_op_type type;
int error;
};
int dpif_recv_set(struct dpif *, bool enable);
-int dpif_recv(struct dpif *, struct dpif_upcall *, struct ofpbuf *);
+int dpif_handlers_set(struct dpif *, uint32_t n_handlers);
+int dpif_recv(struct dpif *, uint32_t handler_id, struct dpif_upcall *,
+ struct ofpbuf *);
void dpif_recv_purge(struct dpif *);
-void dpif_recv_wait(struct dpif *);
+void dpif_recv_wait(struct dpif *, uint32_t handler_id);
\f
/* Miscellaneous. */
projects / cascardo / ovs.git / blobdiff