2 * Copyright (c) 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 #include "ofproto-dpif-monitor.h"
29 #include "ofproto-dpif.h"
30 #include "ovs-thread.h"
31 #include "poll-loop.h"
37 VLOG_DEFINE_THIS_MODULE(ofproto_dpif_monitor);
39 /* Converts the time in millisecond to heap priority. */
40 #define MSEC_TO_PRIO(TIME) (LLONG_MAX - (TIME))
41 /* Converts the heap priority to time in millisecond. */
42 #define PRIO_TO_MSEC(PRIO) (LLONG_MAX - (PRIO))
44 /* Monitored port. It owns references to ofport, bfd, cfm structs. */
46 struct hmap_node hmap_node; /* In monitor_hmap. */
47 struct heap_node heap_node; /* In monitor_heap. */
48 const struct ofport_dpif *ofport; /* The corresponding ofport. */
50 struct cfm *cfm; /* Reference to cfm. */
51 struct bfd *bfd; /* Reference to bfd. */
52 uint8_t hw_addr[OFP_ETH_ALEN]; /* Hardware address. */
55 /* hmap that contains "struct mport"s. */
56 static struct hmap monitor_hmap;
58 /* heap for ordering mport based on bfd/cfm wakeup time. */
59 static struct heap monitor_heap;
61 /* The monitor thread id. */
62 static pthread_t monitor_tid;
63 /* True if the monitor thread is running. */
64 static bool monitor_running;
66 static struct seq *monitor_seq;
67 static struct latch monitor_exit_latch;
68 static struct ovs_rwlock monitor_rwlock = OVS_RWLOCK_INITIALIZER;
70 static void monitor_init(void);
71 static void *monitor_main(void *);
72 static void monitor_run(void);
74 static void mport_register(const struct ofport_dpif *, struct bfd *,
75 struct cfm *, uint8_t[ETH_ADDR_LEN])
76 OVS_REQ_WRLOCK(monitor_rwlock);
77 static void mport_unregister(const struct ofport_dpif *)
78 OVS_REQ_WRLOCK(monitor_rwlock);
79 static void mport_update(struct mport *, struct bfd *, struct cfm *,
80 uint8_t[ETH_ADDR_LEN]) OVS_REQ_WRLOCK(monitor_rwlock);
81 static struct mport *mport_find(const struct ofport_dpif *)
82 OVS_REQ_WRLOCK(monitor_rwlock);
84 /* Tries finding and returning the 'mport' from the monitor_hmap.
85 * If there is no such 'mport', returns NULL. */
87 mport_find(const struct ofport_dpif *ofport) OVS_REQ_WRLOCK(monitor_rwlock)
91 HMAP_FOR_EACH_WITH_HASH (node, hmap_node, hash_pointer(ofport, 0),
93 if (node->ofport == ofport) {
100 /* Creates a new mport and inserts it into monitor_hmap and monitor_heap,
101 * if it doesn't exist. Otherwise, just updates its fields. */
103 mport_register(const struct ofport_dpif *ofport, struct bfd *bfd,
104 struct cfm *cfm, uint8_t *hw_addr)
105 OVS_REQ_WRLOCK(monitor_rwlock)
107 struct mport *mport = mport_find(ofport);
110 mport = xzalloc(sizeof *mport);
111 mport->ofport = ofport;
112 hmap_insert(&monitor_hmap, &mport->hmap_node, hash_pointer(ofport, 0));
113 heap_insert(&monitor_heap, &mport->heap_node, 0);
115 mport_update(mport, bfd, cfm, hw_addr);
118 /* Removes mport from monitor_hmap and monitor_heap and frees it. */
120 mport_unregister(const struct ofport_dpif *ofport)
121 OVS_REQ_WRLOCK(monitor_rwlock)
123 struct mport *mport = mport_find(ofport);
126 mport_update(mport, NULL, NULL, NULL);
127 hmap_remove(&monitor_hmap, &mport->hmap_node);
128 heap_remove(&monitor_heap, &mport->heap_node);
133 /* Updates the fields of an existing mport struct. */
135 mport_update(struct mport *mport, struct bfd *bfd, struct cfm *cfm,
136 uint8_t hw_addr[ETH_ADDR_LEN]) OVS_REQ_WRLOCK(monitor_rwlock)
140 if (mport->cfm != cfm) {
141 cfm_unref(mport->cfm);
142 mport->cfm = cfm_ref(cfm);
144 if (mport->bfd != bfd) {
145 bfd_unref(mport->bfd);
146 mport->bfd = bfd_ref(bfd);
148 if (hw_addr && memcmp(mport->hw_addr, hw_addr, ETH_ADDR_LEN)) {
149 memcpy(mport->hw_addr, hw_addr, ETH_ADDR_LEN);
151 /* If bfd/cfm is added or reconfigured, move the mport on top of the heap
152 * and wakes up the monitor thread. */
153 if (mport->bfd || mport->cfm) {
154 heap_change(&monitor_heap, &mport->heap_node, LLONG_MAX);
155 seq_change(monitor_seq);
160 /* Initializes the global variables. This will only run once. */
164 static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
166 if (ovsthread_once_start(&once)) {
167 hmap_init(&monitor_hmap);
168 monitor_seq = seq_create();
169 ovsthread_once_done(&once);
173 /* The 'main' function for the monitor thread. */
175 monitor_main(void * args OVS_UNUSED)
177 set_subprogram_name("monitor");
178 VLOG_INFO("monitor thread created");
179 while (!latch_is_set(&monitor_exit_latch)) {
180 uint64_t seq = seq_read(monitor_seq);
183 latch_wait(&monitor_exit_latch);
184 seq_wait(monitor_seq, seq);
187 VLOG_INFO("monitor thread terminated");
191 /* Checks the sending of control packets on mports that have timed out.
192 * Sends the control packets if needed. Executes bfd and cfm periodic
193 * functions (run, wait) on those mports. */
197 uint32_t stub[512 / 4];
198 long long int prio_now;
199 struct ofpbuf packet;
201 ofpbuf_use_stub(&packet, stub, sizeof stub);
202 ovs_rwlock_rdlock(&monitor_rwlock);
203 prio_now = MSEC_TO_PRIO(time_msec());
204 /* Peeks the top of heap and checks if we should run this mport. */
205 while (!heap_is_empty(&monitor_heap)
206 && heap_max(&monitor_heap)->priority >= prio_now) {
207 long long int next_wake_time;
210 mport = CONTAINER_OF(heap_max(&monitor_heap), struct mport, heap_node);
211 if (mport->cfm && cfm_should_send_ccm(mport->cfm)) {
212 ofpbuf_clear(&packet);
213 cfm_compose_ccm(mport->cfm, &packet, mport->hw_addr);
214 ofproto_dpif_send_packet(mport->ofport, &packet);
216 if (mport->bfd && bfd_should_send_packet(mport->bfd)) {
217 ofpbuf_clear(&packet);
218 bfd_put_packet(mport->bfd, &packet, mport->hw_addr);
219 ofproto_dpif_send_packet(mport->ofport, &packet);
223 cfm_wait(mport->cfm);
227 bfd_wait(mport->bfd);
229 /* Computes the next wakeup time for this mport. */
230 next_wake_time = MIN(bfd_wake_time(mport->bfd), cfm_wake_time(mport->cfm));
231 heap_change(&monitor_heap, heap_max(&monitor_heap),
232 MSEC_TO_PRIO(next_wake_time));
235 /* Waits on the earliest next wakeup time. */
236 if (!heap_is_empty(&monitor_heap)) {
237 poll_timer_wait_until(PRIO_TO_MSEC(heap_max(&monitor_heap)->priority));
239 ovs_rwlock_unlock(&monitor_rwlock);
240 ofpbuf_uninit(&packet);
244 /* Creates the mport in monitor module if either bfd or cfm
245 * is configured. Otherwise, deletes the mport.
246 * Also checks whether the monitor thread should be started
249 ofproto_dpif_monitor_port_update(const struct ofport_dpif *ofport,
250 struct bfd *bfd, struct cfm *cfm,
251 uint8_t hw_addr[ETH_ADDR_LEN])
254 ovs_rwlock_wrlock(&monitor_rwlock);
256 mport_unregister(ofport);
258 mport_register(ofport, bfd, cfm, hw_addr);
260 ovs_rwlock_unlock(&monitor_rwlock);
262 /* If the monitor thread is not running and the hmap
263 * is not empty, starts it. If it is and the hmap is empty,
265 if (!monitor_running && !hmap_is_empty(&monitor_hmap)) {
266 latch_init(&monitor_exit_latch);
267 xpthread_create(&monitor_tid, NULL, monitor_main, NULL);
268 monitor_running = true;
269 } else if (monitor_running && hmap_is_empty(&monitor_hmap)) {
270 latch_set(&monitor_exit_latch);
271 xpthread_join(monitor_tid, NULL);
272 latch_destroy(&monitor_exit_latch);
273 monitor_running = false;