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72b06300 1/*
7aec165d 2 * Copyright (c) 2009, 2010, 2011 Nicira Networks.
f1588b1f 3 * Copyright (c) 2009 InMon Corp.
72b06300
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4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18#include <config.h>
19#include "ofproto-sflow.h"
20#include <inttypes.h>
21#include <stdlib.h>
22#include "collectors.h"
23#include "dpif.h"
24#include "compiler.h"
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25#include "hash.h"
26#include "hmap.h"
72b06300 27#include "netdev.h"
cdee00fd 28#include "netlink.h"
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29#include "ofpbuf.h"
30#include "ofproto.h"
26233bb4 31#include "packets.h"
72b06300 32#include "poll-loop.h"
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33#include "sflow_api.h"
34#include "socket-util.h"
35#include "timeval.h"
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36#include "vlog.h"
37
d98e6007 38VLOG_DEFINE_THIS_MODULE(sflow);
5136ce49 39
72b06300 40struct ofproto_sflow_port {
0cc96e48 41 struct hmap_node hmap_node; /* In struct ofproto_sflow's "ports" hmap. */
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42 struct netdev *netdev; /* Underlying network device, for stats. */
43 SFLDataSource_instance dsi; /* sFlow library's notion of port number. */
0cc96e48 44 uint16_t odp_port; /* ODP port number. */
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45};
46
47struct ofproto_sflow {
48 struct ofproto *ofproto;
49 struct collectors *collectors;
50 SFLAgent *sflow_agent;
51 struct ofproto_sflow_options *options;
52 struct dpif *dpif;
53 time_t next_tick;
54 size_t n_flood, n_all;
0cc96e48 55 struct hmap ports; /* Contains "struct ofproto_sflow_port"s. */
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56};
57
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58static void ofproto_sflow_del_port__(struct ofproto_sflow *,
59 struct ofproto_sflow_port *);
60
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61#define RECEIVER_INDEX 1
62
63static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
64
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65static bool
66nullable_string_is_equal(const char *a, const char *b)
67{
68 return a ? b && !strcmp(a, b) : !b;
69}
70
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71static bool
72ofproto_sflow_options_equal(const struct ofproto_sflow_options *a,
73 const struct ofproto_sflow_options *b)
74{
81e2083f 75 return (sset_equals(&a->targets, &b->targets)
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76 && a->sampling_rate == b->sampling_rate
77 && a->polling_interval == b->polling_interval
78 && a->header_len == b->header_len
79 && a->sub_id == b->sub_id
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80 && nullable_string_is_equal(a->agent_device, b->agent_device)
81 && nullable_string_is_equal(a->control_ip, b->control_ip));
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82}
83
84static struct ofproto_sflow_options *
85ofproto_sflow_options_clone(const struct ofproto_sflow_options *old)
86{
87 struct ofproto_sflow_options *new = xmemdup(old, sizeof *old);
81e2083f 88 sset_clone(&new->targets, &old->targets);
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89 new->agent_device = old->agent_device ? xstrdup(old->agent_device) : NULL;
90 new->control_ip = old->control_ip ? xstrdup(old->control_ip) : NULL;
91 return new;
92}
93
94static void
95ofproto_sflow_options_destroy(struct ofproto_sflow_options *options)
96{
97 if (options) {
81e2083f 98 sset_destroy(&options->targets);
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99 free(options->agent_device);
100 free(options->control_ip);
101 free(options);
102 }
103}
104
105/* sFlow library callback to allocate memory. */
106static void *
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107sflow_agent_alloc_cb(void *magic OVS_UNUSED, SFLAgent *agent OVS_UNUSED,
108 size_t bytes)
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109{
110 return calloc(1, bytes);
111}
112
113/* sFlow library callback to free memory. */
114static int
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115sflow_agent_free_cb(void *magic OVS_UNUSED, SFLAgent *agent OVS_UNUSED,
116 void *obj)
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117{
118 free(obj);
119 return 0;
120}
121
122/* sFlow library callback to report error. */
123static void
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124sflow_agent_error_cb(void *magic OVS_UNUSED, SFLAgent *agent OVS_UNUSED,
125 char *msg)
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126{
127 VLOG_WARN("sFlow agent error: %s", msg);
128}
129
130/* sFlow library callback to send datagram. */
131static void
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132sflow_agent_send_packet_cb(void *os_, SFLAgent *agent OVS_UNUSED,
133 SFLReceiver *receiver OVS_UNUSED, u_char *pkt,
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134 uint32_t pktLen)
135{
136 struct ofproto_sflow *os = os_;
137 collectors_send(os->collectors, pkt, pktLen);
138}
139
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140static struct ofproto_sflow_port *
141ofproto_sflow_find_port(const struct ofproto_sflow *os, uint16_t odp_port)
142{
143 struct ofproto_sflow_port *osp;
144
4e8e4213 145 HMAP_FOR_EACH_IN_BUCKET (osp, hmap_node,
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146 hash_int(odp_port, 0), &os->ports) {
147 if (osp->odp_port == odp_port) {
148 return osp;
149 }
150 }
151 return NULL;
152}
153
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154static void
155sflow_agent_get_counters(void *os_, SFLPoller *poller,
156 SFL_COUNTERS_SAMPLE_TYPE *cs)
157{
158 struct ofproto_sflow *os = os_;
159 SFLCounters_sample_element elem;
160 struct ofproto_sflow_port *osp;
161 SFLIf_counters *counters;
162 struct netdev_stats stats;
163 enum netdev_flags flags;
164 uint32_t current;
165
0cc96e48 166 osp = ofproto_sflow_find_port(os, poller->bridgePort);
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167 if (!osp) {
168 return;
169 }
170
171 elem.tag = SFLCOUNTERS_GENERIC;
172 counters = &elem.counterBlock.generic;
173 counters->ifIndex = SFL_DS_INDEX(poller->dsi);
174 counters->ifType = 6;
175 if (!netdev_get_features(osp->netdev, &current, NULL, NULL, NULL)) {
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176 /* The values of ifDirection come from MAU MIB (RFC 2668): 0 = unknown,
177 1 = full-duplex, 2 = half-duplex, 3 = in, 4=out */
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178 counters->ifSpeed = netdev_features_to_bps(current);
179 counters->ifDirection = (netdev_features_is_full_duplex(current)
180 ? 1 : 2);
181 } else {
182 counters->ifSpeed = 100000000;
b6dab095 183 counters->ifDirection = 0;
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184 }
185 if (!netdev_get_flags(osp->netdev, &flags) && flags & NETDEV_UP) {
72b06300 186 counters->ifStatus = 1; /* ifAdminStatus up. */
85da620e 187 if (netdev_get_carrier(osp->netdev)) {
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188 counters->ifStatus |= 2; /* ifOperStatus us. */
189 }
190 } else {
191 counters->ifStatus = 0; /* Down. */
192 }
193
194 /* XXX
195 1. Is the multicast counter filled in?
196 2. Does the multicast counter include broadcasts?
197 3. Does the rx_packets counter include multicasts/broadcasts?
198 */
199 netdev_get_stats(osp->netdev, &stats);
200 counters->ifInOctets = stats.rx_bytes;
201 counters->ifInUcastPkts = stats.rx_packets;
202 counters->ifInMulticastPkts = stats.multicast;
203 counters->ifInBroadcastPkts = -1;
204 counters->ifInDiscards = stats.rx_dropped;
205 counters->ifInErrors = stats.rx_errors;
206 counters->ifInUnknownProtos = -1;
207 counters->ifOutOctets = stats.tx_bytes;
208 counters->ifOutUcastPkts = stats.tx_packets;
209 counters->ifOutMulticastPkts = -1;
210 counters->ifOutBroadcastPkts = -1;
211 counters->ifOutDiscards = stats.tx_dropped;
212 counters->ifOutErrors = stats.tx_errors;
213 counters->ifPromiscuousMode = 0;
214
215 SFLADD_ELEMENT(cs, &elem);
216 sfl_poller_writeCountersSample(poller, cs);
217}
218
219/* Obtains an address to use for the local sFlow agent and stores it into
220 * '*agent_addr'. Returns true if successful, false on failure.
221 *
222 * The sFlow agent address should be a local IP address that is persistent and
223 * reachable over the network, if possible. The IP address associated with
224 * 'agent_device' is used if it has one, and otherwise 'control_ip', the IP
225 * address used to talk to the controller. */
226static bool
227sflow_choose_agent_address(const char *agent_device, const char *control_ip,
228 SFLAddress *agent_addr)
229{
230 struct in_addr in4;
231
232 memset(agent_addr, 0, sizeof *agent_addr);
233 agent_addr->type = SFLADDRESSTYPE_IP_V4;
234
235 if (agent_device) {
236 struct netdev *netdev;
237
a4af0040 238 if (!netdev_open_default(agent_device, &netdev)) {
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239 int error = netdev_get_in4(netdev, &in4, NULL);
240 netdev_close(netdev);
241 if (!error) {
242 goto success;
243 }
244 }
245 }
246
247 if (control_ip && !lookup_ip(control_ip, &in4)) {
248 goto success;
249 }
250
251 VLOG_ERR("could not determine IP address for sFlow agent");
252 return false;
253
254success:
6506f45c 255 agent_addr->address.ip_v4.addr = (OVS_FORCE uint32_t) in4.s_addr;
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256 return true;
257}
258
259void
260ofproto_sflow_clear(struct ofproto_sflow *os)
261{
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262 if (os->sflow_agent) {
263 sfl_agent_release(os->sflow_agent);
264 os->sflow_agent = NULL;
265 }
266 collectors_destroy(os->collectors);
267 os->collectors = NULL;
268 ofproto_sflow_options_destroy(os->options);
269 os->options = NULL;
270
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271 /* Turn off sampling to save CPU cycles. */
272 dpif_set_sflow_probability(os->dpif, 0);
273}
274
275bool
276ofproto_sflow_is_enabled(const struct ofproto_sflow *os)
277{
278 return os->collectors != NULL;
279}
280
281struct ofproto_sflow *
282ofproto_sflow_create(struct dpif *dpif)
283{
284 struct ofproto_sflow *os;
285
286 os = xcalloc(1, sizeof *os);
287 os->dpif = dpif;
288 os->next_tick = time_now() + 1;
0cc96e48 289 hmap_init(&os->ports);
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290 return os;
291}
292
293void
294ofproto_sflow_destroy(struct ofproto_sflow *os)
295{
296 if (os) {
0cc96e48 297 struct ofproto_sflow_port *osp, *next;
32d9dc11 298
72b06300 299 ofproto_sflow_clear(os);
4e8e4213 300 HMAP_FOR_EACH_SAFE (osp, next, hmap_node, &os->ports) {
0cc96e48 301 ofproto_sflow_del_port__(os, osp);
32d9dc11 302 }
0cc96e48 303 hmap_destroy(&os->ports);
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304 free(os);
305 }
306}
307
308static void
309ofproto_sflow_add_poller(struct ofproto_sflow *os,
310 struct ofproto_sflow_port *osp, uint16_t odp_port)
311{
312 SFLPoller *poller = sfl_agent_addPoller(os->sflow_agent, &osp->dsi, os,
313 sflow_agent_get_counters);
314 sfl_poller_set_sFlowCpInterval(poller, os->options->polling_interval);
315 sfl_poller_set_sFlowCpReceiver(poller, RECEIVER_INDEX);
316 sfl_poller_set_bridgePort(poller, odp_port);
317}
318
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319static void
320ofproto_sflow_add_sampler(struct ofproto_sflow *os,
5586445e 321 struct ofproto_sflow_port *osp)
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322{
323 SFLSampler *sampler = sfl_agent_addSampler(os->sflow_agent, &osp->dsi);
5586445e
NM
324 sfl_sampler_set_sFlowFsPacketSamplingRate(sampler, os->options->sampling_rate);
325 sfl_sampler_set_sFlowFsMaximumHeaderSize(sampler, os->options->header_len);
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326 sfl_sampler_set_sFlowFsReceiver(sampler, RECEIVER_INDEX);
327}
328
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329void
330ofproto_sflow_add_port(struct ofproto_sflow *os, uint16_t odp_port,
331 const char *netdev_name)
332{
333 struct ofproto_sflow_port *osp;
334 struct netdev *netdev;
335 uint32_t ifindex;
336 int error;
337
338 ofproto_sflow_del_port(os, odp_port);
339
340 /* Open network device. */
a4af0040 341 error = netdev_open_default(netdev_name, &netdev);
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342 if (error) {
343 VLOG_WARN_RL(&rl, "failed to open network device \"%s\": %s",
344 netdev_name, strerror(error));
345 return;
346 }
347
348 /* Add to table of ports. */
349 osp = xmalloc(sizeof *osp);
350 osp->netdev = netdev;
351 ifindex = netdev_get_ifindex(netdev);
352 if (ifindex <= 0) {
353 ifindex = (os->sflow_agent->subId << 16) + odp_port;
354 }
355 SFL_DS_SET(osp->dsi, 0, ifindex, 0);
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356 osp->odp_port = odp_port;
357 hmap_insert(&os->ports, &osp->hmap_node, hash_int(odp_port, 0));
72b06300 358
5586445e 359 /* Add poller and sampler. */
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360 if (os->sflow_agent) {
361 ofproto_sflow_add_poller(os, osp, odp_port);
5586445e 362 ofproto_sflow_add_sampler(os, osp);
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363 }
364}
365
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366static void
367ofproto_sflow_del_port__(struct ofproto_sflow *os,
368 struct ofproto_sflow_port *osp)
369{
370 if (os->sflow_agent) {
371 sfl_agent_removePoller(os->sflow_agent, &osp->dsi);
372 sfl_agent_removeSampler(os->sflow_agent, &osp->dsi);
373 }
374 netdev_close(osp->netdev);
375 hmap_remove(&os->ports, &osp->hmap_node);
376 free(osp);
377}
378
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379void
380ofproto_sflow_del_port(struct ofproto_sflow *os, uint16_t odp_port)
381{
0cc96e48 382 struct ofproto_sflow_port *osp = ofproto_sflow_find_port(os, odp_port);
72b06300 383 if (osp) {
0cc96e48 384 ofproto_sflow_del_port__(os, osp);
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385 }
386}
387
388void
389ofproto_sflow_set_options(struct ofproto_sflow *os,
390 const struct ofproto_sflow_options *options)
391{
392 struct ofproto_sflow_port *osp;
72b06300 393 bool options_changed;
72b06300 394 SFLReceiver *receiver;
72b06300
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395 SFLAddress agentIP;
396 time_t now;
72b06300 397
81e2083f 398 if (sset_is_empty(&options->targets) || !options->sampling_rate) {
a68813c3
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399 /* No point in doing any work if there are no targets or nothing to
400 * sample. */
401 ofproto_sflow_clear(os);
402 return;
403 }
404
72b06300
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405 options_changed = (!os->options
406 || !ofproto_sflow_options_equal(options, os->options));
407
408 /* Configure collectors if options have changed or if we're shortchanged in
409 * collectors (which indicates that opening one or more of the configured
410 * collectors failed, so that we should retry). */
411 if (options_changed
81e2083f 412 || collectors_count(os->collectors) < sset_count(&options->targets)) {
72b06300 413 collectors_destroy(os->collectors);
02ef592c
BP
414 collectors_create(&options->targets, SFL_DEFAULT_COLLECTOR_PORT,
415 &os->collectors);
72b06300 416 if (os->collectors == NULL) {
a68813c3
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417 VLOG_WARN_RL(&rl, "no collectors could be initialized, "
418 "sFlow disabled");
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419 ofproto_sflow_clear(os);
420 return;
421 }
422 }
423
424 /* Avoid reconfiguring if options didn't change. */
425 if (!options_changed) {
426 return;
427 }
428 ofproto_sflow_options_destroy(os->options);
429 os->options = ofproto_sflow_options_clone(options);
430
431 /* Choose agent IP address. */
432 if (!sflow_choose_agent_address(options->agent_device,
433 options->control_ip, &agentIP)) {
434 ofproto_sflow_clear(os);
435 return;
436 }
437
438 /* Create agent. */
439 VLOG_INFO("creating sFlow agent %d", options->sub_id);
440 if (os->sflow_agent) {
441 sfl_agent_release(os->sflow_agent);
442 }
443 os->sflow_agent = xcalloc(1, sizeof *os->sflow_agent);
c73814a3 444 now = time_wall();
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445 sfl_agent_init(os->sflow_agent,
446 &agentIP,
447 options->sub_id,
448 now, /* Boot time. */
449 now, /* Current time. */
450 os, /* Pointer supplied to callbacks. */
451 sflow_agent_alloc_cb,
452 sflow_agent_free_cb,
453 sflow_agent_error_cb,
454 sflow_agent_send_packet_cb);
455
456 receiver = sfl_agent_addReceiver(os->sflow_agent);
e53df206 457 sfl_receiver_set_sFlowRcvrOwner(receiver, "Open vSwitch sFlow");
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458 sfl_receiver_set_sFlowRcvrTimeout(receiver, 0xffffffff);
459
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460 /* Set the sampling_rate down in the datapath. */
461 dpif_set_sflow_probability(os->dpif,
462 MAX(1, UINT32_MAX / options->sampling_rate));
463
56fd8edf 464 /* Add samplers and pollers for the currently known ports. */
4e8e4213 465 HMAP_FOR_EACH (osp, hmap_node, &os->ports) {
0cc96e48 466 ofproto_sflow_add_poller(os, osp, osp->odp_port);
5586445e 467 ofproto_sflow_add_sampler(os, osp);
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468 }
469}
470
c1e98da1
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471static int
472ofproto_sflow_odp_port_to_ifindex(const struct ofproto_sflow *os,
473 uint16_t odp_port)
474{
0cc96e48 475 struct ofproto_sflow_port *osp = ofproto_sflow_find_port(os, odp_port);
c1e98da1
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476 return osp ? SFL_DS_INDEX(osp->dsi) : 0;
477}
478
72b06300 479void
856081f6
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480ofproto_sflow_received(struct ofproto_sflow *os,
481 const struct dpif_upcall *upcall,
482 const struct flow *flow)
72b06300
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483{
484 SFL_FLOW_SAMPLE_TYPE fs;
485 SFLFlow_sample_element hdrElem;
486 SFLSampled_header *header;
487 SFLFlow_sample_element switchElem;
56fd8edf 488 SFLSampler *sampler;
cdee00fd 489 unsigned int left;
856081f6 490 struct nlattr *a;
cdee00fd 491 size_t n_outputs;
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492
493 /* Build a flow sample */
494 memset(&fs, 0, sizeof fs);
856081f6 495 fs.input = ofproto_sflow_odp_port_to_ifindex(os, flow->in_port);
72b06300 496 fs.output = 0; /* Filled in correctly below. */
856081f6 497 fs.sample_pool = upcall->sample_pool;
72b06300 498
56fd8edf
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499 /* We are going to give it to the sampler that represents this input port.
500 * By implementing "ingress-only" sampling like this we ensure that we
501 * never have to offer the same sample to more than one sampler. */
502 sampler = sfl_agent_getSamplerByIfIndex(os->sflow_agent, fs.input);
503 if (!sampler) {
504 VLOG_WARN_RL(&rl, "no sampler for input ifIndex (%"PRIu32")",
505 fs.input);
506 return;
507 }
508
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509 /* Sampled header. */
510 memset(&hdrElem, 0, sizeof hdrElem);
511 hdrElem.tag = SFLFLOW_HEADER;
512 header = &hdrElem.flowType.header;
513 header->header_protocol = SFLHEADER_ETHERNET_ISO8023;
c62caaa3
NM
514 /* The frame_length should include the Ethernet FCS (4 bytes),
515 but it has already been stripped, so we need to add 4 here. */
856081f6 516 header->frame_length = upcall->packet->size + 4;
c62caaa3
NM
517 /* Ethernet FCS stripped off. */
518 header->stripped = 4;
856081f6
BP
519 header->header_length = MIN(upcall->packet->size,
520 sampler->sFlowFsMaximumHeaderSize);
521 header->header_bytes = upcall->packet->data;
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522
523 /* Add extended switch element. */
524 memset(&switchElem, 0, sizeof(switchElem));
525 switchElem.tag = SFLFLOW_EX_SWITCH;
856081f6
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526 switchElem.flowType.sw.src_vlan = vlan_tci_to_vid(flow->vlan_tci);
527 switchElem.flowType.sw.src_priority = vlan_tci_to_pcp(flow->vlan_tci);
f9727d74
NM
528 /* Initialize the output VLAN and priority to be the same as the input,
529 but these fields can be overriden below if affected by an action. */
530 switchElem.flowType.sw.dst_vlan = switchElem.flowType.sw.src_vlan;
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531 switchElem.flowType.sw.dst_priority = switchElem.flowType.sw.src_priority;
532
533 /* Figure out the output ports. */
534 n_outputs = 0;
856081f6 535 NL_ATTR_FOR_EACH_UNSAFE (a, left, upcall->actions, upcall->actions_len) {
cdee00fd 536 ovs_be16 tci;
72b06300 537
cdee00fd 538 switch (nl_attr_type(a)) {
7aec165d 539 case ODP_ACTION_ATTR_OUTPUT:
cdee00fd
BP
540 fs.output = ofproto_sflow_odp_port_to_ifindex(os,
541 nl_attr_get_u32(a));
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542 n_outputs++;
543 break;
544
7aec165d 545 case ODP_ACTION_ATTR_SET_DL_TCI:
cdee00fd 546 tci = nl_attr_get_be16(a);
27bcf966
BP
547 switchElem.flowType.sw.dst_vlan = vlan_tci_to_vid(tci);
548 switchElem.flowType.sw.dst_priority = vlan_tci_to_pcp(tci);
72b06300
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549 break;
550
551 default:
552 break;
553 }
554 }
46b47a41
BP
555
556 /* Set output port, as defined by http://www.sflow.org/sflow_version_5.txt
557 (search for "Input/output port information"). */
216114e0
BP
558 if (!n_outputs) {
559 /* This value indicates that the packet was dropped for an unknown
560 * reason. */
561 fs.output = 0x40000000 | 256;
562 } else if (n_outputs > 1 || !fs.output) {
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563 /* Setting the high bit means "multiple output ports". */
564 fs.output = 0x80000000 | n_outputs;
565 }
566
567 /* Submit the flow sample to be encoded into the next datagram. */
568 SFLADD_ELEMENT(&fs, &hdrElem);
569 SFLADD_ELEMENT(&fs, &switchElem);
570 sfl_sampler_writeFlowSample(sampler, &fs);
571}
572
72b06300
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573void
574ofproto_sflow_run(struct ofproto_sflow *os)
575{
576 if (ofproto_sflow_is_enabled(os)) {
577 time_t now = time_now();
578 if (now >= os->next_tick) {
c73814a3 579 sfl_agent_tick(os->sflow_agent, time_wall());
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580 os->next_tick = now + 1;
581 }
582 }
583}
584
585void
586ofproto_sflow_wait(struct ofproto_sflow *os)
587{
588 if (ofproto_sflow_is_enabled(os)) {
7cf8b266 589 poll_timer_wait_until(os->next_tick * 1000LL);
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590 }
591}