Commit | Line | Data |
---|---|---|
ce5aef0b MD |
1 | /* |
2 | * ltt-probes.c | |
3 | * | |
4 | * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * | |
6 | * Holds LTTng probes registry. | |
7 | * | |
8 | * Dual LGPL v2.1/GPL v2 license. | |
9 | */ | |
10 | ||
8d8a24c8 MD |
11 | #include <string.h> |
12 | #include <errno.h> | |
13 | #include <urcu/list.h> | |
1f18504e | 14 | #include <urcu/hlist.h> |
4318ae1b | 15 | #include <lttng/ust-events.h> |
a3bb4b27 | 16 | #include <assert.h> |
c8fcf224 | 17 | #include <helper.h> |
48740cab | 18 | #include <ctype.h> |
ce5aef0b | 19 | |
8165c8da | 20 | #include "ltt-tracer-core.h" |
1f18504e MD |
21 | #include "jhash.h" |
22 | #include "error.h" | |
8165c8da MD |
23 | |
24 | /* | |
17dfb34b | 25 | * probe list is protected by ust_lock()/ust_unlock(). |
8165c8da | 26 | */ |
8d8a24c8 | 27 | static CDS_LIST_HEAD(probe_list); |
ce5aef0b | 28 | |
1f18504e MD |
29 | /* |
30 | * Loglevel hash table, containing the active loglevels. | |
31 | * Protected by ust lock. | |
32 | */ | |
33 | #define LOGLEVEL_HASH_BITS 6 | |
34 | #define LOGLEVEL_TABLE_SIZE (1 << LOGLEVEL_HASH_BITS) | |
35 | static struct cds_hlist_head loglevel_table[LOGLEVEL_TABLE_SIZE]; | |
36 | ||
df854e41 MD |
37 | static |
38 | const struct lttng_probe_desc *find_provider(const char *provider) | |
39 | { | |
40 | struct lttng_probe_desc *iter; | |
41 | ||
42 | cds_list_for_each_entry(iter, &probe_list, head) { | |
43 | if (!strcmp(iter->provider, provider)) | |
44 | return iter; | |
45 | } | |
46 | return NULL; | |
47 | } | |
48 | ||
ce5aef0b MD |
49 | static |
50 | const struct lttng_event_desc *find_event(const char *name) | |
51 | { | |
52 | struct lttng_probe_desc *probe_desc; | |
53 | int i; | |
54 | ||
8d8a24c8 | 55 | cds_list_for_each_entry(probe_desc, &probe_list, head) { |
ce5aef0b | 56 | for (i = 0; i < probe_desc->nr_events; i++) { |
df854e41 MD |
57 | if (!strcmp(probe_desc->event_desc[i]->name, name)) |
58 | return probe_desc->event_desc[i]; | |
ce5aef0b MD |
59 | } |
60 | } | |
61 | return NULL; | |
62 | } | |
63 | ||
64 | int ltt_probe_register(struct lttng_probe_desc *desc) | |
65 | { | |
df854e41 | 66 | struct lttng_probe_desc *iter; |
ce5aef0b MD |
67 | int ret = 0; |
68 | int i; | |
69 | ||
17dfb34b | 70 | ust_lock(); |
df854e41 MD |
71 | if (find_provider(desc->provider)) { |
72 | ret = -EEXIST; | |
73 | goto end; | |
74 | } | |
ce5aef0b MD |
75 | /* |
76 | * TODO: This is O(N^2). Turn into a hash table when probe registration | |
77 | * overhead becomes an issue. | |
78 | */ | |
79 | for (i = 0; i < desc->nr_events; i++) { | |
df854e41 | 80 | if (find_event(desc->event_desc[i]->name)) { |
ce5aef0b MD |
81 | ret = -EEXIST; |
82 | goto end; | |
83 | } | |
84 | } | |
df854e41 MD |
85 | |
86 | /* | |
87 | * We sort the providers by struct lttng_probe_desc pointer | |
88 | * address. | |
89 | */ | |
90 | cds_list_for_each_entry_reverse(iter, &probe_list, head) { | |
91 | BUG_ON(iter == desc); /* Should never be in the list twice */ | |
92 | if (iter < desc) { | |
93 | /* We belong to the location right after iter. */ | |
94 | cds_list_add(&desc->head, &iter->head); | |
95 | goto desc_added; | |
96 | } | |
97 | } | |
98 | /* We should be added at the head of the list */ | |
8d8a24c8 | 99 | cds_list_add(&desc->head, &probe_list); |
df854e41 | 100 | desc_added: |
8165c8da MD |
101 | |
102 | /* | |
103 | * fix the events awaiting probe load. | |
104 | */ | |
105 | for (i = 0; i < desc->nr_events; i++) { | |
df854e41 | 106 | ret = pending_probe_fix_events(desc->event_desc[i]); |
8165c8da MD |
107 | assert(!ret); |
108 | } | |
ce5aef0b | 109 | end: |
17dfb34b | 110 | ust_unlock(); |
ce5aef0b MD |
111 | return ret; |
112 | } | |
ce5aef0b MD |
113 | |
114 | void ltt_probe_unregister(struct lttng_probe_desc *desc) | |
115 | { | |
17dfb34b | 116 | ust_lock(); |
8d8a24c8 | 117 | cds_list_del(&desc->head); |
17dfb34b | 118 | ust_unlock(); |
ce5aef0b | 119 | } |
ce5aef0b | 120 | |
8165c8da MD |
121 | /* |
122 | * called with UST lock held. | |
123 | */ | |
ce5aef0b MD |
124 | const struct lttng_event_desc *ltt_event_get(const char *name) |
125 | { | |
126 | const struct lttng_event_desc *event; | |
ce5aef0b | 127 | |
ce5aef0b | 128 | event = find_event(name); |
ce5aef0b MD |
129 | if (!event) |
130 | return NULL; | |
ce5aef0b MD |
131 | return event; |
132 | } | |
ce5aef0b MD |
133 | |
134 | void ltt_event_put(const struct lttng_event_desc *event) | |
135 | { | |
ce5aef0b | 136 | } |
c8fcf224 MD |
137 | |
138 | void ltt_probes_prune_event_list(struct lttng_ust_tracepoint_list *list) | |
139 | { | |
140 | struct tp_list_entry *list_entry, *tmp; | |
141 | ||
142 | cds_list_for_each_entry_safe(list_entry, tmp, &list->head, head) { | |
143 | cds_list_del(&list_entry->head); | |
144 | free(list_entry); | |
145 | } | |
146 | } | |
147 | ||
148 | /* | |
149 | * called with UST lock held. | |
150 | */ | |
151 | int ltt_probes_get_event_list(struct lttng_ust_tracepoint_list *list) | |
152 | { | |
153 | struct lttng_probe_desc *probe_desc; | |
154 | int i; | |
155 | ||
156 | CDS_INIT_LIST_HEAD(&list->head); | |
157 | cds_list_for_each_entry(probe_desc, &probe_list, head) { | |
158 | for (i = 0; i < probe_desc->nr_events; i++) { | |
159 | struct tp_list_entry *list_entry; | |
160 | ||
161 | list_entry = zmalloc(sizeof(*list_entry)); | |
162 | if (!list_entry) | |
163 | goto err_nomem; | |
164 | cds_list_add(&list_entry->head, &list->head); | |
165 | strncpy(list_entry->tp.name, | |
166 | probe_desc->event_desc[i]->name, | |
167 | LTTNG_UST_SYM_NAME_LEN); | |
168 | list_entry->tp.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0'; | |
169 | if (!probe_desc->event_desc[i]->loglevel) { | |
170 | list_entry->tp.loglevel[0] = '\0'; | |
171 | list_entry->tp.loglevel_value = 0; | |
172 | } else { | |
173 | strncpy(list_entry->tp.loglevel, | |
174 | (*probe_desc->event_desc[i]->loglevel)->identifier, | |
175 | LTTNG_UST_SYM_NAME_LEN); | |
176 | list_entry->tp.loglevel[LTTNG_UST_SYM_NAME_LEN - 1] = '\0'; | |
177 | list_entry->tp.loglevel_value = | |
178 | (*probe_desc->event_desc[i]->loglevel)->value; | |
179 | } | |
180 | } | |
181 | } | |
182 | if (cds_list_empty(&list->head)) | |
183 | list->iter = NULL; | |
184 | else | |
185 | list->iter = | |
186 | cds_list_first_entry(&list->head, struct tp_list_entry, head); | |
187 | return 0; | |
188 | ||
189 | err_nomem: | |
190 | ltt_probes_prune_event_list(list); | |
191 | return -ENOMEM; | |
192 | } | |
193 | ||
194 | /* | |
195 | * Return current iteration position, advance internal iterator to next. | |
196 | * Return NULL if end of list. | |
197 | */ | |
198 | struct lttng_ust_tracepoint_iter * | |
199 | lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list) | |
200 | { | |
201 | struct tp_list_entry *entry; | |
202 | ||
203 | if (!list->iter) | |
204 | return NULL; | |
205 | entry = list->iter; | |
206 | if (entry->head.next == &list->head) | |
207 | list->iter = NULL; | |
208 | else | |
209 | list->iter = cds_list_entry(entry->head.next, | |
210 | struct tp_list_entry, head); | |
211 | return &entry->tp; | |
212 | } | |
1f18504e MD |
213 | |
214 | /* | |
215 | * Get loglevel if the loglevel is present in the loglevel hash table. | |
216 | * Must be called with ust lock held. | |
217 | * Returns NULL if not present. | |
218 | */ | |
219 | struct loglevel_entry *get_loglevel(const char *name) | |
220 | { | |
221 | struct cds_hlist_head *head; | |
222 | struct cds_hlist_node *node; | |
223 | struct loglevel_entry *e; | |
224 | uint32_t hash = jhash(name, strlen(name), 0); | |
225 | ||
226 | head = &loglevel_table[hash & (LOGLEVEL_TABLE_SIZE - 1)]; | |
227 | cds_hlist_for_each_entry(e, node, head, hlist) { | |
228 | if (!strcmp(name, e->name)) | |
229 | return e; | |
230 | } | |
231 | return NULL; | |
232 | } | |
233 | ||
48740cab MD |
234 | struct loglevel_entry *get_loglevel_value(int64_t value) |
235 | { | |
236 | char name[LTTNG_UST_SYM_NAME_LEN]; | |
237 | int ret; | |
238 | ||
239 | ret = snprintf(name, LTTNG_UST_SYM_NAME_LEN, "%lld", (long long) value); | |
240 | if (ret < 0) | |
241 | return NULL; | |
242 | return get_loglevel(name); | |
243 | } | |
244 | ||
1f18504e MD |
245 | /* |
246 | * marshall all probes/all events and create those that fit the | |
247 | * loglevel. Add them to the events list as created. | |
248 | */ | |
249 | static | |
574a6217 MD |
250 | void _probes_create_loglevel_events(struct loglevel_entry *entry, |
251 | struct session_loglevel *loglevel) | |
1f18504e MD |
252 | { |
253 | struct lttng_probe_desc *probe_desc; | |
7ee3cc56 | 254 | struct lttng_ust_event event_param; |
1f18504e MD |
255 | int i; |
256 | ||
257 | cds_list_for_each_entry(probe_desc, &probe_list, head) { | |
258 | for (i = 0; i < probe_desc->nr_events; i++) { | |
259 | const struct tracepoint_loglevel_entry *ev_ll; | |
7ee3cc56 | 260 | const struct lttng_event_desc *event_desc; |
5e87eb4a | 261 | int match = 0; |
1f18504e | 262 | |
7ee3cc56 MD |
263 | event_desc = probe_desc->event_desc[i]; |
264 | if (!(event_desc->loglevel)) | |
1f18504e | 265 | continue; |
7ee3cc56 | 266 | ev_ll = *event_desc->loglevel; |
48740cab MD |
267 | if (isalpha(entry->name[0])) { |
268 | if (atoll(entry->name) == ev_ll->value) { | |
269 | match = 1; | |
270 | } | |
271 | } else if (!strcmp(ev_ll->identifier, entry->name)) { | |
272 | match = 1; | |
273 | } | |
274 | ||
275 | if (match) { | |
1f18504e MD |
276 | struct ltt_event *ev; |
277 | int ret; | |
278 | ||
7ee3cc56 MD |
279 | memcpy(&event_param, &loglevel->event_param, |
280 | sizeof(event_param)); | |
281 | memcpy(event_param.name, | |
282 | event_desc->name, | |
283 | sizeof(event_param.name)); | |
1f18504e MD |
284 | /* create event */ |
285 | ret = ltt_event_create(loglevel->chan, | |
7ee3cc56 | 286 | &event_param, NULL, |
1f18504e | 287 | &ev); |
7ee3cc56 MD |
288 | if (ret) { |
289 | DBG("Error creating event"); | |
1f18504e | 290 | continue; |
7ee3cc56 | 291 | } |
1f18504e MD |
292 | cds_list_add(&ev->loglevel_list, |
293 | &loglevel->events); | |
294 | } | |
1f18504e MD |
295 | } |
296 | } | |
297 | } | |
298 | ||
299 | /* | |
300 | * Add the loglevel to the loglevel hash table. Must be called with | |
301 | * ust lock held. | |
302 | */ | |
574a6217 | 303 | struct session_loglevel *add_loglevel(const char *name, |
1f18504e MD |
304 | struct ltt_channel *chan, |
305 | struct lttng_ust_event *event_param) | |
306 | { | |
307 | struct cds_hlist_head *head; | |
308 | struct cds_hlist_node *node; | |
309 | struct loglevel_entry *e; | |
574a6217 | 310 | struct session_loglevel *sl; |
1f18504e MD |
311 | size_t name_len = strlen(name) + 1; |
312 | uint32_t hash = jhash(name, name_len-1, 0); | |
574a6217 | 313 | int found = 0; |
1f18504e | 314 | |
574a6217 | 315 | /* loglevel entry */ |
1f18504e MD |
316 | head = &loglevel_table[hash & (LOGLEVEL_TABLE_SIZE - 1)]; |
317 | cds_hlist_for_each_entry(e, node, head, hlist) { | |
318 | if (!strcmp(name, e->name)) { | |
574a6217 MD |
319 | found = 1; |
320 | break; | |
321 | } | |
322 | } | |
323 | ||
324 | if (!found) { | |
325 | /* | |
326 | * Using zmalloc here to allocate a variable length element. Could | |
327 | * cause some memory fragmentation if overused. | |
328 | */ | |
329 | e = zmalloc(sizeof(struct loglevel_entry) + name_len); | |
330 | if (!e) | |
331 | return ERR_PTR(-ENOMEM); | |
332 | memcpy(&e->name[0], name, name_len); | |
333 | cds_hlist_add_head(&e->hlist, head); | |
d5201d38 | 334 | CDS_INIT_LIST_HEAD(&e->session_list); |
574a6217 MD |
335 | } |
336 | ||
337 | /* session loglevel */ | |
338 | cds_list_for_each_entry(sl, &e->session_list, session_list) { | |
339 | if (chan == sl->chan) { | |
340 | DBG("loglevel %s busy for this channel", name); | |
1f18504e MD |
341 | return ERR_PTR(-EEXIST); /* Already there */ |
342 | } | |
343 | } | |
574a6217 MD |
344 | sl = zmalloc(sizeof(struct session_loglevel)); |
345 | if (!sl) | |
1f18504e | 346 | return ERR_PTR(-ENOMEM); |
574a6217 MD |
347 | sl->chan = chan; |
348 | sl->enabled = 1; | |
349 | memcpy(&sl->event_param, event_param, sizeof(sl->event_param)); | |
d5201d38 | 350 | sl->event_param.instrumentation = LTTNG_UST_TRACEPOINT; |
574a6217 MD |
351 | CDS_INIT_LIST_HEAD(&sl->events); |
352 | cds_list_add(&sl->list, &chan->session->loglevels); | |
353 | cds_list_add(&sl->session_list, &e->session_list); | |
2981744d | 354 | sl->entry = e; |
574a6217 MD |
355 | _probes_create_loglevel_events(e, sl); |
356 | return sl; | |
1f18504e MD |
357 | } |
358 | ||
359 | /* | |
360 | * Remove the loglevel from the loglevel hash table. Must be called with | |
361 | * ust_lock held. Only called at session teardown. | |
362 | */ | |
574a6217 | 363 | void _remove_loglevel(struct session_loglevel *loglevel) |
1f18504e MD |
364 | { |
365 | struct ltt_event *ev, *tmp; | |
366 | ||
367 | /* | |
368 | * Just remove the events owned (for enable/disable) by this | |
369 | * loglevel from the list. The session teardown will take care | |
370 | * of freeing the event memory. | |
371 | */ | |
372 | cds_list_for_each_entry_safe(ev, tmp, &loglevel->events, list) { | |
373 | cds_list_del(&ev->list); | |
374 | } | |
574a6217 | 375 | cds_list_del(&loglevel->session_list); |
1f18504e | 376 | cds_list_del(&loglevel->list); |
574a6217 MD |
377 | if (cds_list_empty(&loglevel->entry->session_list)) { |
378 | cds_hlist_del(&loglevel->entry->hlist); | |
379 | free(loglevel->entry); | |
380 | } | |
1f18504e MD |
381 | free(loglevel); |
382 | } | |
383 | ||
574a6217 | 384 | int ltt_loglevel_enable(struct session_loglevel *loglevel) |
1f18504e MD |
385 | { |
386 | struct ltt_event *ev; | |
387 | int ret; | |
388 | ||
389 | if (loglevel->enabled) | |
390 | return -EEXIST; | |
391 | cds_list_for_each_entry(ev, &loglevel->events, list) { | |
392 | ret = ltt_event_enable(ev); | |
393 | if (ret) { | |
394 | DBG("Error: enable error.\n"); | |
395 | return ret; | |
396 | } | |
397 | } | |
398 | loglevel->enabled = 1; | |
399 | return 0; | |
400 | } | |
401 | ||
574a6217 | 402 | int ltt_loglevel_disable(struct session_loglevel *loglevel) |
1f18504e MD |
403 | { |
404 | struct ltt_event *ev; | |
405 | int ret; | |
406 | ||
407 | if (!loglevel->enabled) | |
408 | return -EEXIST; | |
409 | cds_list_for_each_entry(ev, &loglevel->events, list) { | |
410 | ret = ltt_event_disable(ev); | |
411 | if (ret) { | |
412 | DBG("Error: disable error.\n"); | |
413 | return ret; | |
414 | } | |
415 | } | |
416 | loglevel->enabled = 0; | |
417 | return 0; | |
418 | } |