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67337c4a MD |
1 | // SPDX-License-Identifier: MIT |
2 | /* | |
3 | * Copyright 2022 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
4 | */ | |
5 | ||
6 | #include <side/trace.h> | |
7 | #include <string.h> | |
b1bf768c | 8 | #include <assert.h> |
67337c4a MD |
9 | |
10 | #include "rcu.h" | |
11 | #include "list.h" | |
12 | ||
13 | /* Top 8 bits reserved for kernel tracer use. */ | |
14 | #if SIDE_BITS_PER_LONG == 64 | |
15 | # define SIDE_EVENT_ENABLED_KERNEL_MASK 0xFF00000000000000ULL | |
16 | # define SIDE_EVENT_ENABLED_KERNEL_USER_EVENT_MASK 0x8000000000000000ULL | |
17 | ||
18 | /* Allow 2^56 tracer references on an event. */ | |
19 | # define SIDE_EVENT_ENABLED_USER_MASK 0x00FFFFFFFFFFFFFFULL | |
20 | #else | |
21 | # define SIDE_EVENT_ENABLED_KERNEL_MASK 0xFF000000UL | |
22 | # define SIDE_EVENT_ENABLED_KERNEL_USER_EVENT_MASK 0x80000000UL | |
23 | ||
24 | /* Allow 2^24 tracer references on an event. */ | |
25 | # define SIDE_EVENT_ENABLED_USER_MASK 0x00FFFFFFUL | |
26 | #endif | |
27 | ||
28 | struct side_events_register_handle { | |
29 | struct side_list_node node; | |
30 | struct side_event_description **events; | |
31 | uint32_t nr_events; | |
32 | }; | |
33 | ||
34 | struct side_tracer_handle { | |
35 | struct side_list_node node; | |
36 | void (*cb)(enum side_tracer_notification notif, | |
37 | struct side_event_description **events, uint32_t nr_events, void *priv); | |
38 | void *priv; | |
39 | }; | |
40 | ||
867b4725 MD |
41 | struct side_callback { |
42 | union { | |
43 | void (*call)(const struct side_event_description *desc, | |
44 | const struct side_arg_vec *side_arg_vec, | |
45 | void *priv); | |
46 | void (*call_variadic)(const struct side_event_description *desc, | |
47 | const struct side_arg_vec *side_arg_vec, | |
48 | const struct side_arg_dynamic_struct *var_struct, | |
49 | void *priv); | |
50 | } u; | |
51 | void *priv; | |
92c377f9 | 52 | void *key; |
867b4725 MD |
53 | }; |
54 | ||
67337c4a MD |
55 | static struct side_rcu_gp_state rcu_gp; |
56 | ||
57 | /* | |
58 | * Lazy initialization for early use within library constructors. | |
59 | */ | |
60 | static bool initialized; | |
61 | /* | |
62 | * Do not register/unregister any more events after destructor. | |
63 | */ | |
64 | static bool finalized; | |
65 | ||
66 | /* | |
67 | * Recursive mutex to allow tracer callbacks to use the side API. | |
68 | */ | |
69 | static pthread_mutex_t side_lock = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP; | |
70 | ||
71 | static DEFINE_SIDE_LIST_HEAD(side_events_list); | |
72 | static DEFINE_SIDE_LIST_HEAD(side_tracer_list); | |
73 | ||
74be90b7 MD |
74 | /* |
75 | * Callback filter key for state dump. | |
76 | */ | |
77 | static __thread void *filter_key; | |
78 | ||
67337c4a MD |
79 | /* |
80 | * The empty callback has a NULL function callback pointer, which stops | |
81 | * iteration on the array of callbacks immediately. | |
82 | */ | |
867b4725 | 83 | const char side_empty_callback[sizeof(struct side_callback)]; |
67337c4a | 84 | |
74be90b7 MD |
85 | static |
86 | void _side_call(const struct side_event_state *event_state, const struct side_arg_vec *side_arg_vec, void *key) | |
67337c4a MD |
87 | { |
88 | struct side_rcu_read_state rcu_read_state; | |
b2a84b9f | 89 | const struct side_event_state_0 *es0; |
67337c4a MD |
90 | const struct side_callback *side_cb; |
91 | uintptr_t enabled; | |
92 | ||
93 | if (side_unlikely(finalized)) | |
94 | return; | |
95 | if (side_unlikely(!initialized)) | |
96 | side_init(); | |
b2a84b9f MD |
97 | if (side_unlikely(event_state->version != 0)) |
98 | abort(); | |
49aea3ef | 99 | es0 = side_container_of(event_state, const struct side_event_state_0, parent); |
7269a8a3 | 100 | assert(!(es0->desc->flags & SIDE_EVENT_FLAG_VARIADIC)); |
b2a84b9f | 101 | enabled = __atomic_load_n(&es0->enabled, __ATOMIC_RELAXED); |
67337c4a MD |
102 | if (side_unlikely(enabled & SIDE_EVENT_ENABLED_KERNEL_USER_EVENT_MASK)) { |
103 | // TODO: call kernel write. | |
104 | } | |
105 | side_rcu_read_begin(&rcu_gp, &rcu_read_state); | |
92c377f9 MD |
106 | for (side_cb = side_rcu_dereference(es0->callbacks); side_cb->u.call != NULL; side_cb++) { |
107 | /* A NULL key is always a match. */ | |
108 | if (key && side_cb->key && side_cb->key != key) | |
109 | continue; | |
7269a8a3 | 110 | side_cb->u.call(es0->desc, side_arg_vec, side_cb->priv); |
92c377f9 | 111 | } |
67337c4a MD |
112 | side_rcu_read_end(&rcu_gp, &rcu_read_state); |
113 | } | |
114 | ||
92c377f9 MD |
115 | void side_call(const struct side_event_state *event_state, const struct side_arg_vec *side_arg_vec) |
116 | { | |
74be90b7 | 117 | _side_call(event_state, side_arg_vec, NULL); |
92c377f9 MD |
118 | } |
119 | ||
74be90b7 MD |
120 | void side_call_key(const struct side_event_state *event_state, const struct side_arg_vec *side_arg_vec) |
121 | { | |
122 | _side_call(event_state, side_arg_vec, filter_key); | |
123 | } | |
124 | ||
125 | static | |
126 | void _side_call_variadic(const struct side_event_state *event_state, | |
67337c4a | 127 | const struct side_arg_vec *side_arg_vec, |
92c377f9 MD |
128 | const struct side_arg_dynamic_struct *var_struct, |
129 | void *key) | |
67337c4a MD |
130 | { |
131 | struct side_rcu_read_state rcu_read_state; | |
b2a84b9f | 132 | const struct side_event_state_0 *es0; |
67337c4a MD |
133 | const struct side_callback *side_cb; |
134 | uintptr_t enabled; | |
135 | ||
136 | if (side_unlikely(finalized)) | |
137 | return; | |
138 | if (side_unlikely(!initialized)) | |
139 | side_init(); | |
b2a84b9f MD |
140 | if (side_unlikely(event_state->version != 0)) |
141 | abort(); | |
49aea3ef | 142 | es0 = side_container_of(event_state, const struct side_event_state_0, parent); |
7269a8a3 | 143 | assert(es0->desc->flags & SIDE_EVENT_FLAG_VARIADIC); |
b2a84b9f | 144 | enabled = __atomic_load_n(&es0->enabled, __ATOMIC_RELAXED); |
67337c4a MD |
145 | if (side_unlikely(enabled & SIDE_EVENT_ENABLED_KERNEL_USER_EVENT_MASK)) { |
146 | // TODO: call kernel write. | |
147 | } | |
148 | side_rcu_read_begin(&rcu_gp, &rcu_read_state); | |
92c377f9 MD |
149 | for (side_cb = side_rcu_dereference(es0->callbacks); side_cb->u.call_variadic != NULL; side_cb++) { |
150 | /* A NULL key is always a match. */ | |
151 | if (key && side_cb->key && side_cb->key != key) | |
152 | continue; | |
7269a8a3 | 153 | side_cb->u.call_variadic(es0->desc, side_arg_vec, var_struct, side_cb->priv); |
92c377f9 | 154 | } |
67337c4a MD |
155 | side_rcu_read_end(&rcu_gp, &rcu_read_state); |
156 | } | |
157 | ||
92c377f9 MD |
158 | void side_call_variadic(const struct side_event_state *event_state, |
159 | const struct side_arg_vec *side_arg_vec, | |
160 | const struct side_arg_dynamic_struct *var_struct) | |
161 | { | |
74be90b7 MD |
162 | _side_call_variadic(event_state, side_arg_vec, var_struct, NULL); |
163 | } | |
164 | ||
165 | void side_call_variadic_key(const struct side_event_state *event_state, | |
166 | const struct side_arg_vec *side_arg_vec, | |
167 | const struct side_arg_dynamic_struct *var_struct) | |
168 | { | |
169 | _side_call_variadic(event_state, side_arg_vec, var_struct, filter_key); | |
92c377f9 MD |
170 | } |
171 | ||
67337c4a MD |
172 | static |
173 | const struct side_callback *side_tracer_callback_lookup( | |
174 | const struct side_event_description *desc, | |
92c377f9 | 175 | void *call, void *priv, void *key) |
67337c4a | 176 | { |
0b9e59d6 | 177 | struct side_event_state *event_state = side_ptr_get(desc->state); |
b2a84b9f | 178 | const struct side_event_state_0 *es0; |
67337c4a MD |
179 | const struct side_callback *cb; |
180 | ||
b2a84b9f MD |
181 | if (side_unlikely(event_state->version != 0)) |
182 | abort(); | |
49aea3ef | 183 | es0 = side_container_of(event_state, const struct side_event_state_0, parent); |
7269a8a3 | 184 | for (cb = es0->callbacks; cb->u.call != NULL; cb++) { |
92c377f9 | 185 | if ((void *) cb->u.call == call && cb->priv == priv && cb->key == key) |
67337c4a MD |
186 | return cb; |
187 | } | |
188 | return NULL; | |
189 | } | |
190 | ||
191 | static | |
192 | int _side_tracer_callback_register(struct side_event_description *desc, | |
92c377f9 | 193 | void *call, void *priv, void *key) |
67337c4a | 194 | { |
0b9e59d6 | 195 | struct side_event_state *event_state; |
67337c4a | 196 | struct side_callback *old_cb, *new_cb; |
b2a84b9f | 197 | struct side_event_state_0 *es0; |
67337c4a MD |
198 | int ret = SIDE_ERROR_OK; |
199 | uint32_t old_nr_cb; | |
200 | ||
201 | if (!call) | |
202 | return SIDE_ERROR_INVAL; | |
203 | if (finalized) | |
204 | return SIDE_ERROR_EXITING; | |
205 | if (!initialized) | |
206 | side_init(); | |
207 | pthread_mutex_lock(&side_lock); | |
0b9e59d6 | 208 | event_state = side_ptr_get(desc->state); |
b2a84b9f MD |
209 | if (side_unlikely(event_state->version != 0)) |
210 | abort(); | |
49aea3ef | 211 | es0 = side_container_of(event_state, struct side_event_state_0, parent); |
3cac1780 | 212 | old_nr_cb = es0->nr_callbacks; |
67337c4a MD |
213 | if (old_nr_cb == UINT32_MAX) { |
214 | ret = SIDE_ERROR_INVAL; | |
215 | goto unlock; | |
216 | } | |
217 | /* Reject duplicate (call, priv) tuples. */ | |
92c377f9 | 218 | if (side_tracer_callback_lookup(desc, call, priv, key)) { |
67337c4a MD |
219 | ret = SIDE_ERROR_EXIST; |
220 | goto unlock; | |
221 | } | |
7269a8a3 | 222 | old_cb = (struct side_callback *) es0->callbacks; |
67337c4a MD |
223 | /* old_nr_cb + 1 (new cb) + 1 (NULL) */ |
224 | new_cb = (struct side_callback *) calloc(old_nr_cb + 2, sizeof(struct side_callback)); | |
225 | if (!new_cb) { | |
226 | ret = SIDE_ERROR_NOMEM; | |
227 | goto unlock; | |
228 | } | |
229 | memcpy(new_cb, old_cb, old_nr_cb); | |
230 | if (desc->flags & SIDE_EVENT_FLAG_VARIADIC) | |
231 | new_cb[old_nr_cb].u.call_variadic = | |
232 | (side_tracer_callback_variadic_func) call; | |
233 | else | |
234 | new_cb[old_nr_cb].u.call = | |
235 | (side_tracer_callback_func) call; | |
236 | new_cb[old_nr_cb].priv = priv; | |
92c377f9 | 237 | new_cb[old_nr_cb].key = key; |
f60d8121 | 238 | /* High order bits are already zeroed. */ |
7269a8a3 | 239 | side_rcu_assign_pointer(es0->callbacks, new_cb); |
67337c4a MD |
240 | side_rcu_wait_grace_period(&rcu_gp); |
241 | if (old_nr_cb) | |
242 | free(old_cb); | |
3cac1780 | 243 | es0->nr_callbacks++; |
67337c4a MD |
244 | /* Increment concurrently with kernel setting the top bits. */ |
245 | if (!old_nr_cb) | |
b2a84b9f | 246 | (void) __atomic_add_fetch(&es0->enabled, 1, __ATOMIC_RELAXED); |
67337c4a MD |
247 | unlock: |
248 | pthread_mutex_unlock(&side_lock); | |
249 | return ret; | |
250 | } | |
251 | ||
252 | int side_tracer_callback_register(struct side_event_description *desc, | |
253 | side_tracer_callback_func call, | |
92c377f9 | 254 | void *priv, void *key) |
67337c4a MD |
255 | { |
256 | if (desc->flags & SIDE_EVENT_FLAG_VARIADIC) | |
257 | return SIDE_ERROR_INVAL; | |
92c377f9 | 258 | return _side_tracer_callback_register(desc, (void *) call, priv, key); |
67337c4a MD |
259 | } |
260 | ||
261 | int side_tracer_callback_variadic_register(struct side_event_description *desc, | |
262 | side_tracer_callback_variadic_func call_variadic, | |
92c377f9 | 263 | void *priv, void *key) |
67337c4a MD |
264 | { |
265 | if (!(desc->flags & SIDE_EVENT_FLAG_VARIADIC)) | |
266 | return SIDE_ERROR_INVAL; | |
92c377f9 | 267 | return _side_tracer_callback_register(desc, (void *) call_variadic, priv, key); |
67337c4a MD |
268 | } |
269 | ||
270 | static int _side_tracer_callback_unregister(struct side_event_description *desc, | |
92c377f9 | 271 | void *call, void *priv, void *key) |
67337c4a | 272 | { |
0b9e59d6 | 273 | struct side_event_state *event_state; |
67337c4a MD |
274 | struct side_callback *old_cb, *new_cb; |
275 | const struct side_callback *cb_pos; | |
b2a84b9f | 276 | struct side_event_state_0 *es0; |
67337c4a MD |
277 | uint32_t pos_idx; |
278 | int ret = SIDE_ERROR_OK; | |
279 | uint32_t old_nr_cb; | |
280 | ||
281 | if (!call) | |
282 | return SIDE_ERROR_INVAL; | |
283 | if (finalized) | |
284 | return SIDE_ERROR_EXITING; | |
285 | if (!initialized) | |
286 | side_init(); | |
287 | pthread_mutex_lock(&side_lock); | |
0b9e59d6 | 288 | event_state = side_ptr_get(desc->state); |
b2a84b9f MD |
289 | if (side_unlikely(event_state->version != 0)) |
290 | abort(); | |
49aea3ef | 291 | es0 = side_container_of(event_state, struct side_event_state_0, parent); |
92c377f9 | 292 | cb_pos = side_tracer_callback_lookup(desc, call, priv, key); |
67337c4a MD |
293 | if (!cb_pos) { |
294 | ret = SIDE_ERROR_NOENT; | |
295 | goto unlock; | |
296 | } | |
3cac1780 | 297 | old_nr_cb = es0->nr_callbacks; |
7269a8a3 | 298 | old_cb = (struct side_callback *) es0->callbacks; |
67337c4a MD |
299 | if (old_nr_cb == 1) { |
300 | new_cb = (struct side_callback *) &side_empty_callback; | |
301 | } else { | |
7269a8a3 | 302 | pos_idx = cb_pos - es0->callbacks; |
67337c4a MD |
303 | /* Remove entry at pos_idx. */ |
304 | /* old_nr_cb - 1 (removed cb) + 1 (NULL) */ | |
305 | new_cb = (struct side_callback *) calloc(old_nr_cb, sizeof(struct side_callback)); | |
306 | if (!new_cb) { | |
307 | ret = SIDE_ERROR_NOMEM; | |
308 | goto unlock; | |
309 | } | |
310 | memcpy(new_cb, old_cb, pos_idx); | |
311 | memcpy(&new_cb[pos_idx], &old_cb[pos_idx + 1], old_nr_cb - pos_idx - 1); | |
312 | } | |
f60d8121 | 313 | /* High order bits are already zeroed. */ |
7269a8a3 | 314 | side_rcu_assign_pointer(es0->callbacks, new_cb); |
67337c4a MD |
315 | side_rcu_wait_grace_period(&rcu_gp); |
316 | free(old_cb); | |
3cac1780 | 317 | es0->nr_callbacks--; |
67337c4a MD |
318 | /* Decrement concurrently with kernel setting the top bits. */ |
319 | if (old_nr_cb == 1) | |
b2a84b9f | 320 | (void) __atomic_add_fetch(&es0->enabled, -1, __ATOMIC_RELAXED); |
67337c4a MD |
321 | unlock: |
322 | pthread_mutex_unlock(&side_lock); | |
323 | return ret; | |
324 | } | |
325 | ||
326 | int side_tracer_callback_unregister(struct side_event_description *desc, | |
327 | side_tracer_callback_func call, | |
92c377f9 | 328 | void *priv, void *key) |
67337c4a MD |
329 | { |
330 | if (desc->flags & SIDE_EVENT_FLAG_VARIADIC) | |
331 | return SIDE_ERROR_INVAL; | |
92c377f9 | 332 | return _side_tracer_callback_unregister(desc, (void *) call, priv, key); |
67337c4a MD |
333 | } |
334 | ||
335 | int side_tracer_callback_variadic_unregister(struct side_event_description *desc, | |
336 | side_tracer_callback_variadic_func call_variadic, | |
92c377f9 | 337 | void *priv, void *key) |
67337c4a MD |
338 | { |
339 | if (!(desc->flags & SIDE_EVENT_FLAG_VARIADIC)) | |
340 | return SIDE_ERROR_INVAL; | |
92c377f9 | 341 | return _side_tracer_callback_unregister(desc, (void *) call_variadic, priv, key); |
67337c4a MD |
342 | } |
343 | ||
344 | struct side_events_register_handle *side_events_register(struct side_event_description **events, uint32_t nr_events) | |
345 | { | |
346 | struct side_events_register_handle *events_handle = NULL; | |
347 | struct side_tracer_handle *tracer_handle; | |
348 | ||
349 | if (finalized) | |
350 | return NULL; | |
351 | if (!initialized) | |
352 | side_init(); | |
353 | events_handle = (struct side_events_register_handle *) | |
354 | calloc(1, sizeof(struct side_events_register_handle)); | |
355 | if (!events_handle) | |
356 | return NULL; | |
357 | events_handle->events = events; | |
358 | events_handle->nr_events = nr_events; | |
359 | ||
360 | pthread_mutex_lock(&side_lock); | |
361 | side_list_insert_node_tail(&side_events_list, &events_handle->node); | |
362 | side_list_for_each_entry(tracer_handle, &side_tracer_list, node) { | |
363 | tracer_handle->cb(SIDE_TRACER_NOTIFICATION_INSERT_EVENTS, | |
364 | events, nr_events, tracer_handle->priv); | |
365 | } | |
366 | pthread_mutex_unlock(&side_lock); | |
367 | //TODO: call event batch register ioctl | |
368 | return events_handle; | |
369 | } | |
370 | ||
371 | static | |
372 | void side_event_remove_callbacks(struct side_event_description *desc) | |
373 | { | |
0b9e59d6 | 374 | struct side_event_state *event_state = side_ptr_get(desc->state); |
b2a84b9f | 375 | struct side_event_state_0 *es0; |
67337c4a | 376 | struct side_callback *old_cb; |
3cac1780 | 377 | uint32_t nr_cb; |
67337c4a | 378 | |
b2a84b9f MD |
379 | if (side_unlikely(event_state->version != 0)) |
380 | abort(); | |
49aea3ef | 381 | es0 = side_container_of(event_state, struct side_event_state_0, parent); |
3cac1780 MD |
382 | nr_cb = es0->nr_callbacks; |
383 | if (!nr_cb) | |
384 | return; | |
7269a8a3 | 385 | old_cb = (struct side_callback *) es0->callbacks; |
b2a84b9f | 386 | (void) __atomic_add_fetch(&es0->enabled, -1, __ATOMIC_RELAXED); |
67337c4a MD |
387 | /* |
388 | * Setting the state back to 0 cb and empty callbacks out of | |
389 | * caution. This should not matter because instrumentation is | |
390 | * unreachable. | |
391 | */ | |
3cac1780 | 392 | es0->nr_callbacks = 0; |
7269a8a3 | 393 | side_rcu_assign_pointer(es0->callbacks, &side_empty_callback); |
67337c4a MD |
394 | /* |
395 | * No need to wait for grace period because instrumentation is | |
396 | * unreachable. | |
397 | */ | |
398 | free(old_cb); | |
399 | } | |
400 | ||
401 | /* | |
402 | * Unregister event handle. At this point, all side events in that | |
403 | * handle should be unreachable. | |
404 | */ | |
405 | void side_events_unregister(struct side_events_register_handle *events_handle) | |
406 | { | |
407 | struct side_tracer_handle *tracer_handle; | |
408 | uint32_t i; | |
409 | ||
410 | if (!events_handle) | |
411 | return; | |
412 | if (finalized) | |
413 | return; | |
414 | if (!initialized) | |
415 | side_init(); | |
416 | pthread_mutex_lock(&side_lock); | |
417 | side_list_remove_node(&events_handle->node); | |
418 | side_list_for_each_entry(tracer_handle, &side_tracer_list, node) { | |
419 | tracer_handle->cb(SIDE_TRACER_NOTIFICATION_REMOVE_EVENTS, | |
420 | events_handle->events, events_handle->nr_events, | |
421 | tracer_handle->priv); | |
422 | } | |
423 | for (i = 0; i < events_handle->nr_events; i++) { | |
424 | struct side_event_description *event = events_handle->events[i]; | |
425 | ||
426 | /* Skip NULL pointers */ | |
427 | if (!event) | |
428 | continue; | |
429 | side_event_remove_callbacks(event); | |
430 | } | |
431 | pthread_mutex_unlock(&side_lock); | |
432 | //TODO: call event batch unregister ioctl | |
433 | free(events_handle); | |
434 | } | |
435 | ||
436 | struct side_tracer_handle *side_tracer_event_notification_register( | |
437 | void (*cb)(enum side_tracer_notification notif, | |
438 | struct side_event_description **events, uint32_t nr_events, void *priv), | |
439 | void *priv) | |
440 | { | |
441 | struct side_tracer_handle *tracer_handle; | |
442 | struct side_events_register_handle *events_handle; | |
443 | ||
444 | if (finalized) | |
445 | return NULL; | |
446 | if (!initialized) | |
447 | side_init(); | |
448 | tracer_handle = (struct side_tracer_handle *) | |
449 | calloc(1, sizeof(struct side_tracer_handle)); | |
450 | if (!tracer_handle) | |
451 | return NULL; | |
452 | pthread_mutex_lock(&side_lock); | |
453 | tracer_handle->cb = cb; | |
454 | tracer_handle->priv = priv; | |
455 | side_list_insert_node_tail(&side_tracer_list, &tracer_handle->node); | |
456 | side_list_for_each_entry(events_handle, &side_events_list, node) { | |
457 | cb(SIDE_TRACER_NOTIFICATION_INSERT_EVENTS, | |
458 | events_handle->events, events_handle->nr_events, priv); | |
459 | } | |
460 | pthread_mutex_unlock(&side_lock); | |
461 | return tracer_handle; | |
462 | } | |
463 | ||
464 | void side_tracer_event_notification_unregister(struct side_tracer_handle *tracer_handle) | |
465 | { | |
466 | struct side_events_register_handle *events_handle; | |
467 | ||
468 | if (finalized) | |
469 | return; | |
470 | if (!initialized) | |
471 | side_init(); | |
472 | pthread_mutex_lock(&side_lock); | |
473 | side_list_for_each_entry(events_handle, &side_events_list, node) { | |
474 | tracer_handle->cb(SIDE_TRACER_NOTIFICATION_REMOVE_EVENTS, | |
475 | events_handle->events, events_handle->nr_events, | |
476 | tracer_handle->priv); | |
477 | } | |
478 | side_list_remove_node(&tracer_handle->node); | |
479 | pthread_mutex_unlock(&side_lock); | |
be787080 | 480 | free(tracer_handle); |
67337c4a MD |
481 | } |
482 | ||
483 | void side_init(void) | |
484 | { | |
485 | if (initialized) | |
486 | return; | |
487 | side_rcu_gp_init(&rcu_gp); | |
488 | initialized = true; | |
489 | } | |
490 | ||
491 | /* | |
492 | * side_exit() is executed from a library destructor. It can be called | |
493 | * explicitly at application exit as well. Concurrent side API use is | |
494 | * not expected at that point. | |
495 | */ | |
496 | void side_exit(void) | |
497 | { | |
498 | struct side_events_register_handle *handle, *tmp; | |
499 | ||
500 | if (finalized) | |
501 | return; | |
502 | side_list_for_each_entry_safe(handle, tmp, &side_events_list, node) | |
503 | side_events_unregister(handle); | |
504 | side_rcu_gp_exit(&rcu_gp); | |
505 | finalized = true; | |
506 | } |