Commit | Line | Data |
---|---|---|
d0b96690 DG |
1 | /* |
2 | * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com> | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify it | |
5 | * under the terms of the GNU General Public License, version 2 only, as | |
6 | * published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
11 | * more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License along with | |
14 | * this program; if not, write to the Free Software Foundation, Inc., 51 | |
15 | * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
16 | */ | |
17 | #define _GNU_SOURCE | |
18 | #include <assert.h> | |
19 | ||
20 | #include <common/common.h> | |
21 | #include "ust-registry.h" | |
22 | ||
23 | /* | |
24 | * Hash table match function for event in the registry. | |
25 | */ | |
26 | static int ht_match_event(struct cds_lfht_node *node, const void *_key) | |
27 | { | |
28 | struct ust_registry_event *event; | |
29 | const struct ust_registry_event *key; | |
30 | ||
31 | assert(node); | |
32 | assert(_key); | |
33 | ||
34 | event = caa_container_of(node, struct ust_registry_event, node.node); | |
35 | assert(event); | |
36 | key = _key; | |
37 | ||
38 | /* It has to be a perfect match. */ | |
39 | if (strncmp(event->name, key->name, sizeof(event->name)) != 0) { | |
40 | goto no_match; | |
41 | } | |
42 | ||
43 | /* It has to be a perfect match. */ | |
44 | if (strncmp(event->signature, key->signature, | |
45 | strlen(event->signature) != 0)) { | |
46 | goto no_match; | |
47 | } | |
48 | ||
49 | /* Match */ | |
50 | return 1; | |
51 | ||
52 | no_match: | |
53 | return 0; | |
54 | } | |
55 | ||
56 | /* | |
57 | * Allocate event and initialize it. This does NOT set a valid event id from a | |
58 | * registry. | |
59 | */ | |
60 | static struct ust_registry_event *alloc_event(int session_objd, | |
61 | int channel_objd, char *name, char *sig, size_t nr_fields, | |
62 | struct ustctl_field *fields, int loglevel, char *model_emf_uri) | |
63 | { | |
64 | struct ust_registry_event *event = NULL; | |
65 | ||
66 | event = zmalloc(sizeof(*event)); | |
67 | if (!event) { | |
68 | PERROR("zmalloc ust registry event"); | |
69 | goto error; | |
70 | } | |
71 | ||
72 | event->session_objd = session_objd; | |
73 | event->channel_objd = channel_objd; | |
74 | /* Allocated by ustctl. */ | |
75 | event->signature = sig; | |
76 | event->nr_fields = nr_fields; | |
77 | event->fields = fields; | |
78 | event->loglevel = loglevel; | |
79 | event->model_emf_uri = model_emf_uri; | |
80 | if (name) { | |
81 | /* Copy event name and force NULL byte. */ | |
82 | strncpy(event->name, name, sizeof(event->name)); | |
83 | event->name[sizeof(event->name) - 1] = '\0'; | |
84 | } | |
85 | lttng_ht_node_init_str(&event->node, event->name); | |
86 | ||
87 | error: | |
88 | return event; | |
89 | } | |
90 | ||
91 | /* | |
92 | * Free event data structure. This does NOT delete it from any hash table. It's | |
93 | * safe to pass a NULL pointer. This shoudl be called inside a call RCU if the | |
94 | * event is previously deleted from a rcu hash table. | |
95 | */ | |
96 | static void destroy_event(struct ust_registry_event *event) | |
97 | { | |
98 | if (!event) { | |
99 | return; | |
100 | } | |
101 | ||
102 | free(event->fields); | |
103 | free(event->model_emf_uri); | |
104 | free(event->signature); | |
105 | free(event); | |
106 | } | |
107 | ||
108 | /* | |
109 | * Destroy event function call of the call RCU. | |
110 | */ | |
111 | static void destroy_event_rcu(struct rcu_head *head) | |
112 | { | |
113 | struct lttng_ht_node_str *node = | |
114 | caa_container_of(head, struct lttng_ht_node_str, head); | |
115 | struct ust_registry_event *event = | |
116 | caa_container_of(node, struct ust_registry_event, node); | |
117 | ||
118 | destroy_event(event); | |
119 | } | |
120 | ||
121 | /* | |
122 | * Find an event using the name and signature in the given registry. RCU read | |
123 | * side lock MUST be acquired before calling this function and as long as the | |
124 | * event reference is kept by the caller. | |
125 | * | |
126 | * On success, the event pointer is returned else NULL. | |
127 | */ | |
128 | struct ust_registry_event *ust_registry_find_event( | |
129 | struct ust_registry_channel *chan, char *name, char *sig) | |
130 | { | |
131 | struct lttng_ht_node_str *node; | |
132 | struct lttng_ht_iter iter; | |
133 | struct ust_registry_event *event = NULL; | |
134 | struct ust_registry_event key; | |
135 | ||
136 | assert(chan); | |
137 | assert(name); | |
138 | assert(sig); | |
139 | ||
140 | /* Setup key for the match function. */ | |
141 | strncpy(key.name, name, sizeof(key.name)); | |
142 | key.name[sizeof(key.name) - 1] = '\0'; | |
143 | key.signature = sig; | |
144 | ||
145 | cds_lfht_lookup(chan->ht->ht, chan->ht->hash_fct(name, lttng_ht_seed), | |
146 | chan->ht->match_fct, &key, &iter.iter); | |
147 | node = lttng_ht_iter_get_node_str(&iter); | |
148 | if (!node) { | |
149 | goto end; | |
150 | } | |
151 | event = caa_container_of(node, struct ust_registry_event, node); | |
152 | ||
153 | end: | |
154 | return event; | |
155 | } | |
156 | ||
157 | /* | |
158 | * Create a ust_registry_event from the given parameters and add it to the | |
159 | * registry hash table. If event_id is valid, it is set with the newly created | |
160 | * event id. | |
161 | * | |
162 | * On success, return 0 else a negative value. The created event MUST be unique | |
163 | * so on duplicate entry -EINVAL is returned. On error, event_id is untouched. | |
164 | * | |
165 | * Should be called with session registry mutex held. | |
166 | */ | |
167 | int ust_registry_create_event(struct ust_registry_session *session, | |
45893984 DG |
168 | uint64_t chan_key, int session_objd, int channel_objd, char *name, |
169 | char *sig, size_t nr_fields, struct ustctl_field *fields, int loglevel, | |
d0b96690 DG |
170 | char *model_emf_uri, uint32_t *event_id) |
171 | { | |
172 | int ret; | |
173 | struct cds_lfht_node *nptr; | |
174 | struct ust_registry_event *event = NULL; | |
45893984 | 175 | struct ust_registry_channel *chan; |
d0b96690 DG |
176 | |
177 | assert(session); | |
d0b96690 DG |
178 | assert(name); |
179 | assert(sig); | |
180 | ||
181 | /* | |
182 | * This should not happen but since it comes from the UST tracer, an | |
183 | * external party, don't assert and simply validate values. | |
184 | */ | |
185 | if (session_objd < 0 || channel_objd < 0) { | |
186 | ret = -EINVAL; | |
187 | goto error; | |
188 | } | |
189 | ||
45893984 DG |
190 | rcu_read_lock(); |
191 | ||
192 | chan = ust_registry_channel_find(session, chan_key); | |
193 | if (!chan) { | |
194 | ret = -EINVAL; | |
195 | goto error_unlock; | |
196 | } | |
197 | ||
d0b96690 DG |
198 | /* Check if we've reached the maximum possible id. */ |
199 | if (ust_registry_is_max_id(chan->used_event_id)) { | |
200 | ret = -ENOENT; | |
45893984 | 201 | goto error_unlock; |
d0b96690 DG |
202 | } |
203 | ||
204 | event = alloc_event(session_objd, channel_objd, name, sig, nr_fields, | |
205 | fields, loglevel, model_emf_uri); | |
206 | if (!event) { | |
207 | ret = -ENOMEM; | |
45893984 | 208 | goto error_unlock; |
d0b96690 DG |
209 | } |
210 | ||
211 | event->id = ust_registry_get_next_event_id(chan); | |
212 | ||
213 | DBG3("UST registry creating event with event: %s, sig: %s, id: %u, " | |
214 | "chan_objd: %u, sess_objd: %u", event->name, event->signature, | |
215 | event->id, event->channel_objd, event->session_objd); | |
216 | ||
d0b96690 DG |
217 | /* |
218 | * This is an add unique with a custom match function for event. The node | |
219 | * are matched using the event name and signature. | |
220 | */ | |
221 | nptr = cds_lfht_add_unique(chan->ht->ht, chan->ht->hash_fct(event->node.key, | |
222 | lttng_ht_seed), chan->ht->match_fct, event, &event->node.node); | |
223 | if (nptr != &event->node.node) { | |
224 | ERR("UST registry create event add unique failed for event: %s, " | |
225 | "sig: %s, id: %u, chan_objd: %u, sess_objd: %u", event->name, | |
226 | event->signature, event->id, event->channel_objd, | |
227 | event->session_objd); | |
228 | ret = -EINVAL; | |
229 | goto error_unlock; | |
230 | } | |
231 | ||
232 | /* Set event id if user wants it. */ | |
233 | if (event_id) { | |
234 | *event_id = event->id; | |
235 | } | |
d0b96690 DG |
236 | |
237 | /* Append to metadata */ | |
238 | ret = ust_metadata_event_statedump(session, chan, event); | |
239 | if (ret) { | |
240 | ERR("Error appending event metadata (errno = %d)", ret); | |
45893984 | 241 | rcu_read_unlock(); |
d0b96690 DG |
242 | return ret; |
243 | } | |
244 | ||
45893984 | 245 | rcu_read_unlock(); |
d0b96690 DG |
246 | return 0; |
247 | ||
248 | error_unlock: | |
249 | rcu_read_unlock(); | |
250 | error: | |
251 | destroy_event(event); | |
252 | return ret; | |
253 | } | |
254 | ||
255 | /* | |
256 | * For a given event in a registry, delete the entry and destroy the event. | |
257 | * This MUST be called within a RCU read side lock section. | |
258 | */ | |
259 | void ust_registry_destroy_event(struct ust_registry_channel *chan, | |
260 | struct ust_registry_event *event) | |
261 | { | |
262 | int ret; | |
263 | struct lttng_ht_iter iter; | |
264 | ||
265 | assert(chan); | |
266 | assert(event); | |
267 | ||
268 | /* Delete the node first. */ | |
269 | iter.iter.node = &event->node.node; | |
270 | ret = lttng_ht_del(chan->ht, &iter); | |
271 | assert(!ret); | |
272 | ||
273 | call_rcu(&event->node.head, destroy_event_rcu); | |
274 | ||
275 | return; | |
276 | } | |
277 | ||
d0b96690 DG |
278 | /* |
279 | * Destroy every element of the registry and free the memory. This does NOT | |
280 | * free the registry pointer since it might not have been allocated before so | |
281 | * it's the caller responsability. | |
282 | * | |
283 | * This MUST be called within a RCU read side lock section. | |
284 | */ | |
45893984 | 285 | static void destroy_channel(struct ust_registry_channel *chan) |
d0b96690 DG |
286 | { |
287 | struct lttng_ht_iter iter; | |
288 | struct ust_registry_event *event; | |
289 | ||
290 | assert(chan); | |
291 | ||
292 | /* Destroy all event associated with this registry. */ | |
293 | cds_lfht_for_each_entry(chan->ht->ht, &iter.iter, event, node.node) { | |
294 | /* Delete the node from the ht and free it. */ | |
295 | ust_registry_destroy_event(chan, event); | |
296 | } | |
297 | lttng_ht_destroy(chan->ht); | |
45893984 DG |
298 | |
299 | free(chan); | |
d0b96690 DG |
300 | } |
301 | ||
302 | /* | |
303 | * Initialize registry with default values. | |
304 | */ | |
45893984 DG |
305 | int ust_registry_channel_add(struct ust_registry_session *session, |
306 | uint64_t key) | |
307 | { | |
308 | int ret = 0; | |
309 | struct ust_registry_channel *chan; | |
310 | ||
311 | assert(session); | |
312 | ||
313 | chan = zmalloc(sizeof(*chan)); | |
314 | if (!chan) { | |
315 | PERROR("zmalloc ust registry channel"); | |
316 | ret = -ENOMEM; | |
317 | goto error; | |
318 | } | |
319 | ||
320 | chan->ht = lttng_ht_new(0, LTTNG_HT_TYPE_STRING); | |
321 | if (!chan->ht) { | |
322 | ret = -ENOMEM; | |
323 | goto error; | |
324 | } | |
325 | ||
326 | /* Set custom match function. */ | |
327 | chan->ht->match_fct = ht_match_event; | |
328 | ||
329 | rcu_read_lock(); | |
330 | lttng_ht_node_init_u64(&chan->node, key); | |
331 | lttng_ht_add_unique_u64(session->channels, &chan->node); | |
332 | rcu_read_unlock(); | |
333 | ||
334 | error: | |
335 | return ret; | |
336 | } | |
337 | ||
338 | /* | |
339 | * Find a channel in the given registry. RCU read side lock MUST be acquired | |
340 | * before calling this function and as long as the event reference is kept by | |
341 | * the caller. | |
342 | * | |
343 | * On success, the pointer is returned else NULL. | |
344 | */ | |
345 | struct ust_registry_channel *ust_registry_channel_find( | |
346 | struct ust_registry_session *session, uint64_t key) | |
347 | { | |
348 | struct lttng_ht_node_u64 *node; | |
349 | struct lttng_ht_iter iter; | |
350 | struct ust_registry_channel *chan = NULL; | |
351 | ||
352 | assert(session); | |
353 | assert(session->channels); | |
354 | ||
355 | lttng_ht_lookup(session->channels, &key, &iter); | |
356 | node = lttng_ht_iter_get_node_u64(&iter); | |
357 | if (!node) { | |
358 | goto end; | |
359 | } | |
360 | chan = caa_container_of(node, struct ust_registry_channel, node); | |
361 | ||
362 | end: | |
363 | return chan; | |
364 | } | |
365 | ||
366 | /* | |
367 | * Remove channel using key from registry and free memory. | |
368 | */ | |
369 | void ust_registry_channel_del_free(struct ust_registry_session *session, | |
370 | uint64_t key) | |
371 | { | |
372 | struct lttng_ht_iter iter; | |
373 | struct ust_registry_channel *chan; | |
374 | ||
375 | assert(session); | |
376 | ||
377 | rcu_read_lock(); | |
378 | chan = ust_registry_channel_find(session, key); | |
379 | if (!chan) { | |
380 | goto end; | |
381 | } | |
382 | ||
383 | iter.iter.node = &chan->node.node; | |
384 | lttng_ht_del(session->channels, &iter); | |
385 | ||
386 | destroy_channel(chan); | |
387 | ||
388 | end: | |
389 | rcu_read_unlock(); | |
390 | return; | |
391 | } | |
392 | ||
393 | /* | |
394 | * Initialize registry with default values and set the newly allocated session | |
395 | * pointer to sessionp. | |
396 | * | |
397 | * Return 0 on success and sessionp is set or else return -1 and sessionp is | |
398 | * kept untouched. | |
399 | */ | |
400 | int ust_registry_session_init(struct ust_registry_session **sessionp, | |
d0b96690 DG |
401 | struct ust_app *app, |
402 | uint32_t bits_per_long, | |
403 | uint32_t uint8_t_alignment, | |
404 | uint32_t uint16_t_alignment, | |
405 | uint32_t uint32_t_alignment, | |
406 | uint32_t uint64_t_alignment, | |
407 | uint32_t long_alignment, | |
408 | int byte_order) | |
409 | { | |
410 | int ret; | |
45893984 | 411 | struct ust_registry_session *session; |
d0b96690 | 412 | |
45893984 DG |
413 | assert(sessionp); |
414 | assert(app); | |
d0b96690 | 415 | |
45893984 DG |
416 | session = zmalloc(sizeof(*session)); |
417 | if (!session) { | |
418 | PERROR("zmalloc ust registry session"); | |
419 | goto error; | |
420 | } | |
d0b96690 DG |
421 | |
422 | pthread_mutex_init(&session->lock, NULL); | |
423 | session->bits_per_long = bits_per_long; | |
424 | session->uint8_t_alignment = uint8_t_alignment; | |
425 | session->uint16_t_alignment = uint16_t_alignment; | |
426 | session->uint32_t_alignment = uint32_t_alignment; | |
427 | session->uint64_t_alignment = uint64_t_alignment; | |
428 | session->long_alignment = long_alignment; | |
429 | session->byte_order = byte_order; | |
430 | ||
45893984 DG |
431 | session->channels = lttng_ht_new(0, LTTNG_HT_TYPE_U64); |
432 | if (!session->channels) { | |
433 | goto error; | |
434 | } | |
435 | ||
d0b96690 DG |
436 | ret = lttng_uuid_generate(session->uuid); |
437 | if (ret) { | |
438 | ERR("Failed to generate UST uuid (errno = %d)", ret); | |
439 | goto error; | |
440 | } | |
441 | ||
442 | pthread_mutex_lock(&session->lock); | |
443 | ret = ust_metadata_session_statedump(session, app); | |
444 | pthread_mutex_unlock(&session->lock); | |
445 | if (ret) { | |
446 | ERR("Failed to generate session metadata (errno = %d)", ret); | |
447 | goto error; | |
448 | } | |
449 | ||
45893984 DG |
450 | *sessionp = session; |
451 | ||
d0b96690 DG |
452 | return 0; |
453 | ||
454 | error: | |
455 | return -1; | |
456 | } | |
457 | ||
458 | /* | |
459 | * Destroy session registry. This does NOT free the given pointer since it | |
460 | * might get passed as a reference. The registry lock should NOT be acquired. | |
461 | */ | |
462 | void ust_registry_session_destroy(struct ust_registry_session *reg) | |
463 | { | |
464 | int ret; | |
45893984 DG |
465 | struct lttng_ht_iter iter; |
466 | struct ust_registry_channel *chan; | |
d0b96690 DG |
467 | |
468 | /* On error, EBUSY can be returned if lock. Code flow error. */ | |
469 | ret = pthread_mutex_destroy(®->lock); | |
470 | assert(!ret); | |
471 | ||
45893984 DG |
472 | rcu_read_lock(); |
473 | /* Destroy all event associated with this registry. */ | |
474 | cds_lfht_for_each_entry(reg->channels->ht, &iter.iter, chan, node.node) { | |
475 | /* Delete the node from the ht and free it. */ | |
476 | ret = lttng_ht_del(reg->channels, &iter); | |
477 | assert(!ret); | |
478 | destroy_channel(chan); | |
479 | } | |
480 | lttng_ht_destroy(reg->channels); | |
481 | rcu_read_unlock(); | |
482 | ||
d0b96690 DG |
483 | free(reg->metadata); |
484 | } |