Commit | Line | Data |
---|---|---|
2691221a MD |
1 | /* |
2 | * lttng-ust-comm.c | |
3 | * | |
4 | * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca> | |
5 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
6 | * | |
7 | * This library is free software; you can redistribute it and/or | |
8 | * modify it under the terms of the GNU Lesser General Public | |
9 | * License as published by the Free Software Foundation; only | |
10 | * version 2.1 of the License. | |
11 | * | |
12 | * This library is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | * Lesser General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU Lesser General Public | |
18 | * License along with this library; if not, write to the Free Software | |
19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
20 | */ | |
21 | ||
80e2814b | 22 | #define _LGPL_SOURCE |
5e1b7b8b | 23 | #define _GNU_SOURCE |
2691221a MD |
24 | #include <sys/types.h> |
25 | #include <sys/socket.h> | |
7fc90dca MD |
26 | #include <sys/mman.h> |
27 | #include <sys/stat.h> | |
58d4b2a2 MD |
28 | #include <sys/types.h> |
29 | #include <sys/wait.h> | |
7fc90dca | 30 | #include <fcntl.h> |
2691221a MD |
31 | #include <unistd.h> |
32 | #include <errno.h> | |
d9e99d10 | 33 | #include <pthread.h> |
11ff9c7d MD |
34 | #include <semaphore.h> |
35 | #include <time.h> | |
1ea11eab | 36 | #include <assert.h> |
e822f505 | 37 | #include <signal.h> |
6f97f9c2 | 38 | #include <limits.h> |
95259bd0 | 39 | #include <urcu/uatomic.h> |
80e2814b | 40 | #include <urcu/futex.h> |
c117fb1b | 41 | #include <urcu/compiler.h> |
1ea11eab | 42 | |
4318ae1b | 43 | #include <lttng/ust-events.h> |
4318ae1b | 44 | #include <lttng/ust-abi.h> |
4318ae1b | 45 | #include <lttng/ust.h> |
7bc53e94 | 46 | #include <lttng/ust-error.h> |
74d81a6c | 47 | #include <lttng/ust-ctl.h> |
8c90a710 | 48 | #include <urcu/tls-compat.h> |
44c72f10 | 49 | #include <ust-comm.h> |
6548fca4 | 50 | #include <ust-fd.h> |
44c72f10 | 51 | #include <usterr-signal-safe.h> |
cd54f6d9 | 52 | #include <helper.h> |
44c72f10 | 53 | #include "tracepoint-internal.h" |
7dd08bec | 54 | #include "lttng-tracer-core.h" |
08114193 | 55 | #include "compat.h" |
6f97f9c2 | 56 | #include "../libringbuffer/rb-init.h" |
cf73e0fe | 57 | #include "lttng-ust-statedump.h" |
f9364363 | 58 | #include "clock.h" |
5e1b7b8b | 59 | #include "../libringbuffer/getcpu.h" |
13efba44 | 60 | #include "getenv.h" |
edaa1431 MD |
61 | |
62 | /* | |
63 | * Has lttng ust comm constructor been called ? | |
64 | */ | |
65 | static int initialized; | |
66 | ||
1ea11eab | 67 | /* |
17dfb34b MD |
68 | * The ust_lock/ust_unlock lock is used as a communication thread mutex. |
69 | * Held when handling a command, also held by fork() to deal with | |
70 | * removal of threads, and by exit path. | |
3327ac33 MD |
71 | * |
72 | * The UST lock is the centralized mutex across UST tracing control and | |
73 | * probe registration. | |
74 | * | |
75 | * ust_exit_mutex must never nest in ust_mutex. | |
d58d1454 | 76 | * |
4770bd47 MD |
77 | * ust_fork_mutex must never nest in ust_mutex. |
78 | * | |
d58d1454 MD |
79 | * ust_mutex_nest is a per-thread nesting counter, allowing the perf |
80 | * counter lazy initialization called by events within the statedump, | |
81 | * which traces while the ust_mutex is held. | |
4770bd47 MD |
82 | * |
83 | * ust_lock nests within the dynamic loader lock (within glibc) because | |
84 | * it is taken within the library constructor. | |
791bf273 MD |
85 | * |
86 | * The ust fd tracker lock nests within the ust_mutex. | |
3327ac33 MD |
87 | */ |
88 | static pthread_mutex_t ust_mutex = PTHREAD_MUTEX_INITIALIZER; | |
89 | ||
d58d1454 MD |
90 | /* Allow nesting the ust_mutex within the same thread. */ |
91 | static DEFINE_URCU_TLS(int, ust_mutex_nest); | |
92 | ||
3327ac33 MD |
93 | /* |
94 | * ust_exit_mutex protects thread_active variable wrt thread exit. It | |
95 | * cannot be done by ust_mutex because pthread_cancel(), which takes an | |
96 | * internal libc lock, cannot nest within ust_mutex. | |
97 | * | |
98 | * It never nests within a ust_mutex. | |
1ea11eab | 99 | */ |
3327ac33 | 100 | static pthread_mutex_t ust_exit_mutex = PTHREAD_MUTEX_INITIALIZER; |
1ea11eab | 101 | |
458d678c PW |
102 | /* |
103 | * ust_fork_mutex protects base address statedump tracing against forks. It | |
104 | * prevents the dynamic loader lock to be taken (by base address statedump | |
105 | * tracing) while a fork is happening, thus preventing deadlock issues with | |
106 | * the dynamic loader lock. | |
107 | */ | |
108 | static pthread_mutex_t ust_fork_mutex = PTHREAD_MUTEX_INITIALIZER; | |
109 | ||
1ea11eab MD |
110 | /* Should the ust comm thread quit ? */ |
111 | static int lttng_ust_comm_should_quit; | |
112 | ||
07b57e5e MD |
113 | /* |
114 | * This variable can be tested by applications to check whether | |
115 | * lttng-ust is loaded. They simply have to define their own | |
116 | * "lttng_ust_loaded" weak symbol, and test it. It is set to 1 by the | |
117 | * library constructor. | |
118 | */ | |
119 | int lttng_ust_loaded __attribute__((weak)); | |
120 | ||
3327ac33 | 121 | /* |
d58d1454 | 122 | * Return 0 on success, -1 if should quit. |
3327ac33 | 123 | * The lock is taken in both cases. |
d58d1454 | 124 | * Signal-safe. |
3327ac33 MD |
125 | */ |
126 | int ust_lock(void) | |
127 | { | |
d58d1454 | 128 | sigset_t sig_all_blocked, orig_mask; |
e446ad80 | 129 | int ret, oldstate; |
d58d1454 | 130 | |
e446ad80 MD |
131 | ret = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldstate); |
132 | if (ret) { | |
133 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
134 | } | |
135 | if (oldstate != PTHREAD_CANCEL_ENABLE) { | |
136 | ERR("pthread_setcancelstate: unexpected oldstate"); | |
137 | } | |
d58d1454 MD |
138 | sigfillset(&sig_all_blocked); |
139 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
140 | if (ret) { | |
141 | ERR("pthread_sigmask: %s", strerror(ret)); | |
142 | } | |
143 | if (!URCU_TLS(ust_mutex_nest)++) | |
144 | pthread_mutex_lock(&ust_mutex); | |
145 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
146 | if (ret) { | |
147 | ERR("pthread_sigmask: %s", strerror(ret)); | |
148 | } | |
3327ac33 MD |
149 | if (lttng_ust_comm_should_quit) { |
150 | return -1; | |
151 | } else { | |
152 | return 0; | |
153 | } | |
154 | } | |
155 | ||
156 | /* | |
157 | * ust_lock_nocheck() can be used in constructors/destructors, because | |
158 | * they are already nested within the dynamic loader lock, and therefore | |
159 | * have exclusive access against execution of liblttng-ust destructor. | |
d58d1454 | 160 | * Signal-safe. |
3327ac33 MD |
161 | */ |
162 | void ust_lock_nocheck(void) | |
163 | { | |
d58d1454 | 164 | sigset_t sig_all_blocked, orig_mask; |
e446ad80 | 165 | int ret, oldstate; |
d58d1454 | 166 | |
e446ad80 MD |
167 | ret = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldstate); |
168 | if (ret) { | |
169 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
170 | } | |
171 | if (oldstate != PTHREAD_CANCEL_ENABLE) { | |
172 | ERR("pthread_setcancelstate: unexpected oldstate"); | |
173 | } | |
d58d1454 MD |
174 | sigfillset(&sig_all_blocked); |
175 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
176 | if (ret) { | |
177 | ERR("pthread_sigmask: %s", strerror(ret)); | |
178 | } | |
179 | if (!URCU_TLS(ust_mutex_nest)++) | |
180 | pthread_mutex_lock(&ust_mutex); | |
181 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
182 | if (ret) { | |
183 | ERR("pthread_sigmask: %s", strerror(ret)); | |
184 | } | |
3327ac33 MD |
185 | } |
186 | ||
d58d1454 MD |
187 | /* |
188 | * Signal-safe. | |
189 | */ | |
3327ac33 MD |
190 | void ust_unlock(void) |
191 | { | |
d58d1454 | 192 | sigset_t sig_all_blocked, orig_mask; |
e446ad80 | 193 | int ret, oldstate; |
d58d1454 MD |
194 | |
195 | sigfillset(&sig_all_blocked); | |
196 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
197 | if (ret) { | |
198 | ERR("pthread_sigmask: %s", strerror(ret)); | |
199 | } | |
200 | if (!--URCU_TLS(ust_mutex_nest)) | |
201 | pthread_mutex_unlock(&ust_mutex); | |
202 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
203 | if (ret) { | |
204 | ERR("pthread_sigmask: %s", strerror(ret)); | |
205 | } | |
e446ad80 MD |
206 | ret = pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldstate); |
207 | if (ret) { | |
208 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
209 | } | |
210 | if (oldstate != PTHREAD_CANCEL_DISABLE) { | |
211 | ERR("pthread_setcancelstate: unexpected oldstate"); | |
212 | } | |
3327ac33 MD |
213 | } |
214 | ||
11ff9c7d MD |
215 | /* |
216 | * Wait for either of these before continuing to the main | |
217 | * program: | |
218 | * - the register_done message from sessiond daemon | |
219 | * (will let the sessiond daemon enable sessions before main | |
220 | * starts.) | |
221 | * - sessiond daemon is not reachable. | |
222 | * - timeout (ensuring applications are resilient to session | |
223 | * daemon problems). | |
224 | */ | |
225 | static sem_t constructor_wait; | |
950aab0c MD |
226 | /* |
227 | * Doing this for both the global and local sessiond. | |
228 | */ | |
a4416702 GAPG |
229 | enum { |
230 | sem_count_initial_value = 4, | |
231 | }; | |
232 | ||
233 | static int sem_count = sem_count_initial_value; | |
11ff9c7d | 234 | |
e8508a49 MD |
235 | /* |
236 | * Counting nesting within lttng-ust. Used to ensure that calling fork() | |
237 | * from liblttng-ust does not execute the pre/post fork handlers. | |
238 | */ | |
8c90a710 | 239 | static DEFINE_URCU_TLS(int, lttng_ust_nest_count); |
e8508a49 | 240 | |
1ea11eab MD |
241 | /* |
242 | * Info about socket and associated listener thread. | |
243 | */ | |
244 | struct sock_info { | |
11ff9c7d | 245 | const char *name; |
1ea11eab | 246 | pthread_t ust_listener; /* listener thread */ |
46050b1a | 247 | int root_handle; |
a4416702 | 248 | int registration_done; |
8d20bf54 | 249 | int allowed; |
44e073f5 | 250 | int global; |
e33f3265 | 251 | int thread_active; |
7fc90dca MD |
252 | |
253 | char sock_path[PATH_MAX]; | |
254 | int socket; | |
32ce8569 | 255 | int notify_socket; |
7fc90dca MD |
256 | |
257 | char wait_shm_path[PATH_MAX]; | |
258 | char *wait_shm_mmap; | |
37dddb65 MD |
259 | /* Keep track of lazy state dump not performed yet. */ |
260 | int statedump_pending; | |
a4416702 | 261 | int initial_statedump_done; |
1ea11eab | 262 | }; |
2691221a MD |
263 | |
264 | /* Socket from app (connect) to session daemon (listen) for communication */ | |
1ea11eab | 265 | struct sock_info global_apps = { |
11ff9c7d | 266 | .name = "global", |
44e073f5 | 267 | .global = 1, |
7fc90dca | 268 | |
46050b1a | 269 | .root_handle = -1, |
a4416702 | 270 | .registration_done = 0, |
ef4a06d9 | 271 | .allowed = 0, |
e33f3265 | 272 | .thread_active = 0, |
7fc90dca | 273 | |
32ce8569 | 274 | .sock_path = LTTNG_DEFAULT_RUNDIR "/" LTTNG_UST_SOCK_FILENAME, |
7fc90dca | 275 | .socket = -1, |
32ce8569 | 276 | .notify_socket = -1, |
7fc90dca | 277 | |
32ce8569 | 278 | .wait_shm_path = "/" LTTNG_UST_WAIT_FILENAME, |
95c25348 | 279 | |
37dddb65 | 280 | .statedump_pending = 0, |
a4416702 | 281 | .initial_statedump_done = 0, |
1ea11eab | 282 | }; |
2691221a MD |
283 | |
284 | /* TODO: allow global_apps_sock_path override */ | |
285 | ||
1ea11eab | 286 | struct sock_info local_apps = { |
11ff9c7d | 287 | .name = "local", |
44e073f5 | 288 | .global = 0, |
46050b1a | 289 | .root_handle = -1, |
a4416702 | 290 | .registration_done = 0, |
8d20bf54 | 291 | .allowed = 0, /* Check setuid bit first */ |
e33f3265 | 292 | .thread_active = 0, |
7fc90dca MD |
293 | |
294 | .socket = -1, | |
32ce8569 | 295 | .notify_socket = -1, |
95c25348 | 296 | |
37dddb65 | 297 | .statedump_pending = 0, |
a4416702 | 298 | .initial_statedump_done = 0, |
1ea11eab | 299 | }; |
2691221a | 300 | |
37ed587a MD |
301 | static int wait_poll_fallback; |
302 | ||
74d81a6c MD |
303 | static const char *cmd_name_mapping[] = { |
304 | [ LTTNG_UST_RELEASE ] = "Release", | |
305 | [ LTTNG_UST_SESSION ] = "Create Session", | |
306 | [ LTTNG_UST_TRACER_VERSION ] = "Get Tracer Version", | |
307 | ||
308 | [ LTTNG_UST_TRACEPOINT_LIST ] = "Create Tracepoint List", | |
309 | [ LTTNG_UST_WAIT_QUIESCENT ] = "Wait for Quiescent State", | |
310 | [ LTTNG_UST_REGISTER_DONE ] = "Registration Done", | |
311 | [ LTTNG_UST_TRACEPOINT_FIELD_LIST ] = "Create Tracepoint Field List", | |
312 | ||
313 | /* Session FD commands */ | |
314 | [ LTTNG_UST_CHANNEL ] = "Create Channel", | |
315 | [ LTTNG_UST_SESSION_START ] = "Start Session", | |
316 | [ LTTNG_UST_SESSION_STOP ] = "Stop Session", | |
317 | ||
318 | /* Channel FD commands */ | |
319 | [ LTTNG_UST_STREAM ] = "Create Stream", | |
320 | [ LTTNG_UST_EVENT ] = "Create Event", | |
321 | ||
322 | /* Event and Channel FD commands */ | |
323 | [ LTTNG_UST_CONTEXT ] = "Create Context", | |
324 | [ LTTNG_UST_FLUSH_BUFFER ] = "Flush Buffer", | |
325 | ||
326 | /* Event, Channel and Session commands */ | |
327 | [ LTTNG_UST_ENABLE ] = "Enable", | |
328 | [ LTTNG_UST_DISABLE ] = "Disable", | |
329 | ||
330 | /* Tracepoint list commands */ | |
331 | [ LTTNG_UST_TRACEPOINT_LIST_GET ] = "List Next Tracepoint", | |
332 | [ LTTNG_UST_TRACEPOINT_FIELD_LIST_GET ] = "List Next Tracepoint Field", | |
333 | ||
334 | /* Event FD commands */ | |
335 | [ LTTNG_UST_FILTER ] = "Create Filter", | |
75582b3a | 336 | [ LTTNG_UST_EXCLUSION ] = "Add exclusions to event", |
74d81a6c MD |
337 | }; |
338 | ||
ff517991 MD |
339 | static const char *str_timeout; |
340 | static int got_timeout_env; | |
341 | ||
7dd08bec | 342 | extern void lttng_ring_buffer_client_overwrite_init(void); |
34a91bdb | 343 | extern void lttng_ring_buffer_client_overwrite_rt_init(void); |
7dd08bec | 344 | extern void lttng_ring_buffer_client_discard_init(void); |
34a91bdb | 345 | extern void lttng_ring_buffer_client_discard_rt_init(void); |
7dd08bec MD |
346 | extern void lttng_ring_buffer_metadata_client_init(void); |
347 | extern void lttng_ring_buffer_client_overwrite_exit(void); | |
34a91bdb | 348 | extern void lttng_ring_buffer_client_overwrite_rt_exit(void); |
7dd08bec | 349 | extern void lttng_ring_buffer_client_discard_exit(void); |
34a91bdb | 350 | extern void lttng_ring_buffer_client_discard_rt_exit(void); |
7dd08bec | 351 | extern void lttng_ring_buffer_metadata_client_exit(void); |
edaa1431 | 352 | |
ef4a06d9 JR |
353 | static char *get_map_shm(struct sock_info *sock_info); |
354 | ||
405be658 MD |
355 | ssize_t lttng_ust_read(int fd, void *buf, size_t len) |
356 | { | |
357 | ssize_t ret; | |
358 | size_t copied = 0, to_copy = len; | |
359 | ||
360 | do { | |
361 | ret = read(fd, buf + copied, to_copy); | |
362 | if (ret > 0) { | |
363 | copied += ret; | |
364 | to_copy -= ret; | |
365 | } | |
366 | } while ((ret > 0 && to_copy > 0) | |
367 | || (ret < 0 && errno == EINTR)); | |
368 | if (ret > 0) { | |
369 | ret = copied; | |
370 | } | |
371 | return ret; | |
372 | } | |
3c6f6263 AM |
373 | /* |
374 | * Returns the HOME directory path. Caller MUST NOT free(3) the returned | |
375 | * pointer. | |
376 | */ | |
377 | static | |
378 | const char *get_lttng_home_dir(void) | |
379 | { | |
380 | const char *val; | |
381 | ||
6f626d28 | 382 | val = (const char *) lttng_getenv("LTTNG_HOME"); |
3c6f6263 AM |
383 | if (val != NULL) { |
384 | return val; | |
385 | } | |
6f626d28 | 386 | return (const char *) lttng_getenv("HOME"); |
3c6f6263 AM |
387 | } |
388 | ||
a903623f MD |
389 | /* |
390 | * Force a read (imply TLS fixup for dlopen) of TLS variables. | |
391 | */ | |
392 | static | |
393 | void lttng_fixup_nest_count_tls(void) | |
394 | { | |
8c90a710 | 395 | asm volatile ("" : : "m" (URCU_TLS(lttng_ust_nest_count))); |
a903623f MD |
396 | } |
397 | ||
d58d1454 MD |
398 | static |
399 | void lttng_fixup_ust_mutex_nest_tls(void) | |
400 | { | |
401 | asm volatile ("" : : "m" (URCU_TLS(ust_mutex_nest))); | |
402 | } | |
403 | ||
1556a549 MD |
404 | /* |
405 | * Fixup urcu bp TLS. | |
406 | */ | |
407 | static | |
408 | void lttng_fixup_urcu_bp_tls(void) | |
409 | { | |
410 | rcu_read_lock(); | |
411 | rcu_read_unlock(); | |
412 | } | |
413 | ||
c362addf MD |
414 | void lttng_ust_fixup_tls(void) |
415 | { | |
416 | lttng_fixup_urcu_bp_tls(); | |
417 | lttng_fixup_ringbuffer_tls(); | |
418 | lttng_fixup_vtid_tls(); | |
419 | lttng_fixup_nest_count_tls(); | |
420 | lttng_fixup_procname_tls(); | |
421 | lttng_fixup_ust_mutex_nest_tls(); | |
b6c0b199 | 422 | lttng_ust_fixup_perf_counter_tls(); |
6548fca4 | 423 | lttng_ust_fixup_fd_tracker_tls(); |
c362addf MD |
424 | } |
425 | ||
32ce8569 MD |
426 | int lttng_get_notify_socket(void *owner) |
427 | { | |
428 | struct sock_info *info = owner; | |
429 | ||
430 | return info->notify_socket; | |
431 | } | |
432 | ||
74d81a6c MD |
433 | static |
434 | void print_cmd(int cmd, int handle) | |
435 | { | |
436 | const char *cmd_name = "Unknown"; | |
437 | ||
fd67a004 MD |
438 | if (cmd >= 0 && cmd < LTTNG_ARRAY_SIZE(cmd_name_mapping) |
439 | && cmd_name_mapping[cmd]) { | |
74d81a6c MD |
440 | cmd_name = cmd_name_mapping[cmd]; |
441 | } | |
fd67a004 MD |
442 | DBG("Message Received \"%s\" (%d), Handle \"%s\" (%d)", |
443 | cmd_name, cmd, | |
74d81a6c MD |
444 | lttng_ust_obj_get_name(handle), handle); |
445 | } | |
446 | ||
ef4a06d9 JR |
447 | static |
448 | int setup_global_apps(void) | |
449 | { | |
450 | int ret = 0; | |
451 | assert(!global_apps.wait_shm_mmap); | |
452 | ||
453 | global_apps.wait_shm_mmap = get_map_shm(&global_apps); | |
454 | if (!global_apps.wait_shm_mmap) { | |
455 | WARN("Unable to get map shm for global apps. Disabling LTTng-UST global tracing."); | |
456 | global_apps.allowed = 0; | |
457 | ret = -EIO; | |
458 | goto error; | |
459 | } | |
460 | ||
461 | global_apps.allowed = 1; | |
462 | error: | |
463 | return ret; | |
464 | } | |
2691221a | 465 | static |
8d20bf54 | 466 | int setup_local_apps(void) |
2691221a | 467 | { |
ef4a06d9 | 468 | int ret = 0; |
2691221a | 469 | const char *home_dir; |
7fc90dca | 470 | uid_t uid; |
2691221a | 471 | |
ef4a06d9 JR |
472 | assert(!local_apps.wait_shm_mmap); |
473 | ||
7fc90dca | 474 | uid = getuid(); |
8d20bf54 MD |
475 | /* |
476 | * Disallow per-user tracing for setuid binaries. | |
477 | */ | |
7fc90dca | 478 | if (uid != geteuid()) { |
9ec6895c | 479 | assert(local_apps.allowed == 0); |
ef4a06d9 JR |
480 | ret = 0; |
481 | goto end; | |
8d20bf54 | 482 | } |
3c6f6263 | 483 | home_dir = get_lttng_home_dir(); |
9ec6895c MD |
484 | if (!home_dir) { |
485 | WARN("HOME environment variable not set. Disabling LTTng-UST per-user tracing."); | |
486 | assert(local_apps.allowed == 0); | |
ef4a06d9 JR |
487 | ret = -ENOENT; |
488 | goto end; | |
9ec6895c MD |
489 | } |
490 | local_apps.allowed = 1; | |
32ce8569 MD |
491 | snprintf(local_apps.sock_path, PATH_MAX, "%s/%s/%s", |
492 | home_dir, | |
493 | LTTNG_DEFAULT_HOME_RUNDIR, | |
494 | LTTNG_UST_SOCK_FILENAME); | |
495 | snprintf(local_apps.wait_shm_path, PATH_MAX, "/%s-%u", | |
496 | LTTNG_UST_WAIT_FILENAME, | |
497 | uid); | |
ef4a06d9 JR |
498 | |
499 | local_apps.wait_shm_mmap = get_map_shm(&local_apps); | |
500 | if (!local_apps.wait_shm_mmap) { | |
501 | WARN("Unable to get map shm for local apps. Disabling LTTng-UST per-user tracing."); | |
502 | local_apps.allowed = 0; | |
503 | ret = -EIO; | |
504 | goto end; | |
505 | } | |
506 | end: | |
507 | return ret; | |
2691221a MD |
508 | } |
509 | ||
ff517991 | 510 | /* |
451d66b2 | 511 | * Get socket timeout, in ms. |
28515902 | 512 | * -1: wait forever. 0: don't wait. >0: timeout, in ms. |
ff517991 MD |
513 | */ |
514 | static | |
515 | long get_timeout(void) | |
516 | { | |
517 | long constructor_delay_ms = LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS; | |
518 | ||
519 | if (!got_timeout_env) { | |
6f626d28 | 520 | str_timeout = lttng_getenv("LTTNG_UST_REGISTER_TIMEOUT"); |
ff517991 MD |
521 | got_timeout_env = 1; |
522 | } | |
523 | if (str_timeout) | |
524 | constructor_delay_ms = strtol(str_timeout, NULL, 10); | |
5cf81d53 MD |
525 | /* All negative values are considered as "-1". */ |
526 | if (constructor_delay_ms < -1) | |
527 | constructor_delay_ms = -1; | |
ff517991 MD |
528 | return constructor_delay_ms; |
529 | } | |
530 | ||
451d66b2 | 531 | /* Timeout for notify socket send and recv. */ |
ff517991 MD |
532 | static |
533 | long get_notify_sock_timeout(void) | |
534 | { | |
535 | return get_timeout(); | |
536 | } | |
537 | ||
451d66b2 MD |
538 | /* Timeout for connecting to cmd and notify sockets. */ |
539 | static | |
540 | long get_connect_sock_timeout(void) | |
541 | { | |
542 | return get_timeout(); | |
543 | } | |
544 | ||
ff517991 | 545 | /* |
28515902 | 546 | * Return values: -1: wait forever. 0: don't wait. 1: timeout wait. |
ff517991 MD |
547 | */ |
548 | static | |
549 | int get_constructor_timeout(struct timespec *constructor_timeout) | |
550 | { | |
551 | long constructor_delay_ms; | |
552 | int ret; | |
553 | ||
554 | constructor_delay_ms = get_timeout(); | |
555 | ||
556 | switch (constructor_delay_ms) { | |
557 | case -1:/* fall-through */ | |
558 | case 0: | |
559 | return constructor_delay_ms; | |
560 | default: | |
561 | break; | |
562 | } | |
563 | ||
564 | /* | |
565 | * If we are unable to find the current time, don't wait. | |
566 | */ | |
567 | ret = clock_gettime(CLOCK_REALTIME, constructor_timeout); | |
568 | if (ret) { | |
28515902 JG |
569 | /* Don't wait. */ |
570 | return 0; | |
ff517991 MD |
571 | } |
572 | constructor_timeout->tv_sec += constructor_delay_ms / 1000UL; | |
573 | constructor_timeout->tv_nsec += | |
574 | (constructor_delay_ms % 1000UL) * 1000000UL; | |
575 | if (constructor_timeout->tv_nsec >= 1000000000UL) { | |
576 | constructor_timeout->tv_sec++; | |
577 | constructor_timeout->tv_nsec -= 1000000000UL; | |
578 | } | |
28515902 | 579 | /* Timeout wait (constructor_delay_ms). */ |
ff517991 MD |
580 | return 1; |
581 | } | |
582 | ||
6f97f9c2 | 583 | static |
9050321d | 584 | void get_allow_blocking(void) |
6f97f9c2 | 585 | { |
9050321d MD |
586 | const char *str_allow_blocking = |
587 | lttng_getenv("LTTNG_UST_ALLOW_BLOCKING"); | |
588 | ||
589 | if (str_allow_blocking) { | |
590 | DBG("%s environment variable is set", | |
591 | "LTTNG_UST_ALLOW_BLOCKING"); | |
592 | lttng_ust_ringbuffer_set_allow_blocking(); | |
6f97f9c2 MD |
593 | } |
594 | } | |
595 | ||
2691221a | 596 | static |
32ce8569 | 597 | int register_to_sessiond(int socket, enum ustctl_socket_type type) |
2691221a | 598 | { |
32ce8569 MD |
599 | return ustcomm_send_reg_msg(socket, |
600 | type, | |
601 | CAA_BITS_PER_LONG, | |
602 | lttng_alignof(uint8_t) * CHAR_BIT, | |
603 | lttng_alignof(uint16_t) * CHAR_BIT, | |
604 | lttng_alignof(uint32_t) * CHAR_BIT, | |
605 | lttng_alignof(uint64_t) * CHAR_BIT, | |
606 | lttng_alignof(unsigned long) * CHAR_BIT); | |
2691221a MD |
607 | } |
608 | ||
d9e99d10 | 609 | static |
57773204 | 610 | int send_reply(int sock, struct ustcomm_ust_reply *lur) |
d9e99d10 | 611 | { |
9eb62b9c | 612 | ssize_t len; |
d3a492d1 | 613 | |
57773204 | 614 | len = ustcomm_send_unix_sock(sock, lur, sizeof(*lur)); |
d3a492d1 | 615 | switch (len) { |
a4be8962 | 616 | case sizeof(*lur): |
d3a492d1 MD |
617 | DBG("message successfully sent"); |
618 | return 0; | |
7bc53e94 MD |
619 | default: |
620 | if (len == -ECONNRESET) { | |
621 | DBG("remote end closed connection"); | |
d3a492d1 MD |
622 | return 0; |
623 | } | |
7bc53e94 MD |
624 | if (len < 0) |
625 | return len; | |
626 | DBG("incorrect message size: %zd", len); | |
627 | return -EINVAL; | |
d3a492d1 MD |
628 | } |
629 | } | |
630 | ||
631 | static | |
a4416702 | 632 | void decrement_sem_count(unsigned int count) |
11ff9c7d MD |
633 | { |
634 | int ret; | |
635 | ||
a4416702 GAPG |
636 | assert(uatomic_read(&sem_count) >= count); |
637 | ||
56cd7e2f | 638 | if (uatomic_read(&sem_count) <= 0) { |
a4416702 | 639 | return; |
56cd7e2f | 640 | } |
a4416702 GAPG |
641 | |
642 | ret = uatomic_add_return(&sem_count, -count); | |
95259bd0 MD |
643 | if (ret == 0) { |
644 | ret = sem_post(&constructor_wait); | |
645 | assert(!ret); | |
646 | } | |
a4416702 GAPG |
647 | } |
648 | ||
649 | static | |
650 | int handle_register_done(struct sock_info *sock_info) | |
651 | { | |
652 | if (sock_info->registration_done) | |
653 | return 0; | |
654 | sock_info->registration_done = 1; | |
655 | ||
656 | decrement_sem_count(1); | |
f1be4090 MD |
657 | if (!sock_info->statedump_pending) { |
658 | sock_info->initial_statedump_done = 1; | |
659 | decrement_sem_count(1); | |
660 | } | |
a4416702 GAPG |
661 | |
662 | return 0; | |
663 | } | |
664 | ||
665 | static | |
666 | int handle_register_failed(struct sock_info *sock_info) | |
667 | { | |
668 | if (sock_info->registration_done) | |
669 | return 0; | |
670 | sock_info->registration_done = 1; | |
671 | sock_info->initial_statedump_done = 1; | |
672 | ||
673 | decrement_sem_count(2); | |
674 | ||
11ff9c7d MD |
675 | return 0; |
676 | } | |
677 | ||
37dddb65 MD |
678 | /* |
679 | * Only execute pending statedump after the constructor semaphore has | |
a4416702 GAPG |
680 | * been posted by the current listener thread. This means statedump will |
681 | * only be performed after the "registration done" command is received | |
682 | * from this thread's session daemon. | |
37dddb65 MD |
683 | * |
684 | * This ensures we don't run into deadlock issues with the dynamic | |
685 | * loader mutex, which is held while the constructor is called and | |
686 | * waiting on the constructor semaphore. All operations requiring this | |
687 | * dynamic loader lock need to be postponed using this mechanism. | |
a4416702 GAPG |
688 | * |
689 | * In a scenario with two session daemons connected to the application, | |
690 | * it is possible that the first listener thread which receives the | |
691 | * registration done command issues its statedump while the dynamic | |
692 | * loader lock is still held by the application constructor waiting on | |
693 | * the semaphore. It will however be allowed to proceed when the | |
694 | * second session daemon sends the registration done command to the | |
695 | * second listener thread. This situation therefore does not produce | |
696 | * a deadlock. | |
37dddb65 MD |
697 | */ |
698 | static | |
699 | void handle_pending_statedump(struct sock_info *sock_info) | |
700 | { | |
a4416702 | 701 | if (sock_info->registration_done && sock_info->statedump_pending) { |
37dddb65 | 702 | sock_info->statedump_pending = 0; |
2932a87f | 703 | pthread_mutex_lock(&ust_fork_mutex); |
37dddb65 | 704 | lttng_handle_pending_statedump(sock_info); |
458d678c | 705 | pthread_mutex_unlock(&ust_fork_mutex); |
a4416702 GAPG |
706 | |
707 | if (!sock_info->initial_statedump_done) { | |
708 | sock_info->initial_statedump_done = 1; | |
709 | decrement_sem_count(1); | |
710 | } | |
37dddb65 MD |
711 | } |
712 | } | |
713 | ||
11ff9c7d MD |
714 | static |
715 | int handle_message(struct sock_info *sock_info, | |
57773204 | 716 | int sock, struct ustcomm_ust_msg *lum) |
d3a492d1 | 717 | { |
1ea11eab | 718 | int ret = 0; |
b61ce3b2 | 719 | const struct lttng_ust_objd_ops *ops; |
57773204 | 720 | struct ustcomm_ust_reply lur; |
ef9ff354 | 721 | union ust_args args; |
8e696cfa | 722 | char ctxstr[LTTNG_UST_SYM_NAME_LEN]; /* App context string. */ |
40003310 | 723 | ssize_t len; |
1ea11eab | 724 | |
46050b1a MD |
725 | memset(&lur, 0, sizeof(lur)); |
726 | ||
3327ac33 | 727 | if (ust_lock()) { |
74d81a6c | 728 | ret = -LTTNG_UST_ERR_EXITING; |
0dafcd63 | 729 | goto error; |
1ea11eab | 730 | } |
9eb62b9c | 731 | |
46050b1a MD |
732 | ops = objd_ops(lum->handle); |
733 | if (!ops) { | |
734 | ret = -ENOENT; | |
0dafcd63 | 735 | goto error; |
1ea11eab | 736 | } |
46050b1a MD |
737 | |
738 | switch (lum->cmd) { | |
11ff9c7d MD |
739 | case LTTNG_UST_REGISTER_DONE: |
740 | if (lum->handle == LTTNG_UST_ROOT_HANDLE) | |
edaa1431 | 741 | ret = handle_register_done(sock_info); |
11ff9c7d MD |
742 | else |
743 | ret = -EINVAL; | |
744 | break; | |
46050b1a MD |
745 | case LTTNG_UST_RELEASE: |
746 | if (lum->handle == LTTNG_UST_ROOT_HANDLE) | |
747 | ret = -EPERM; | |
748 | else | |
1849ef7c | 749 | ret = lttng_ust_objd_unref(lum->handle, 1); |
d9e99d10 | 750 | break; |
2d78951a MD |
751 | case LTTNG_UST_FILTER: |
752 | { | |
753 | /* Receive filter data */ | |
f488575f | 754 | struct lttng_ust_filter_bytecode_node *bytecode; |
2d78951a | 755 | |
cd54f6d9 | 756 | if (lum->u.filter.data_size > FILTER_BYTECODE_MAX_LEN) { |
7bc53e94 | 757 | ERR("Filter data size is too large: %u bytes", |
2d78951a MD |
758 | lum->u.filter.data_size); |
759 | ret = -EINVAL; | |
760 | goto error; | |
761 | } | |
2734ca65 | 762 | |
885b1dfd | 763 | if (lum->u.filter.reloc_offset > lum->u.filter.data_size) { |
7bc53e94 | 764 | ERR("Filter reloc offset %u is not within data", |
2734ca65 CB |
765 | lum->u.filter.reloc_offset); |
766 | ret = -EINVAL; | |
767 | goto error; | |
768 | } | |
769 | ||
cd54f6d9 MD |
770 | bytecode = zmalloc(sizeof(*bytecode) + lum->u.filter.data_size); |
771 | if (!bytecode) { | |
772 | ret = -ENOMEM; | |
773 | goto error; | |
774 | } | |
f488575f | 775 | len = ustcomm_recv_unix_sock(sock, bytecode->bc.data, |
2d78951a MD |
776 | lum->u.filter.data_size); |
777 | switch (len) { | |
778 | case 0: /* orderly shutdown */ | |
779 | ret = 0; | |
cd54f6d9 | 780 | free(bytecode); |
2d78951a | 781 | goto error; |
2d78951a MD |
782 | default: |
783 | if (len == lum->u.filter.data_size) { | |
7bc53e94 | 784 | DBG("filter data received"); |
2d78951a | 785 | break; |
7bc53e94 MD |
786 | } else if (len < 0) { |
787 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
788 | if (len == -ECONNRESET) { | |
789 | ERR("%s remote end closed connection", sock_info->name); | |
790 | ret = len; | |
791 | free(bytecode); | |
792 | goto error; | |
793 | } | |
794 | ret = len; | |
eb8bf361 | 795 | free(bytecode); |
0dafcd63 | 796 | goto error; |
2d78951a | 797 | } else { |
7bc53e94 | 798 | DBG("incorrect filter data message size: %zd", len); |
2d78951a | 799 | ret = -EINVAL; |
cd54f6d9 | 800 | free(bytecode); |
0dafcd63 | 801 | goto error; |
2d78951a MD |
802 | } |
803 | } | |
f488575f MD |
804 | bytecode->bc.len = lum->u.filter.data_size; |
805 | bytecode->bc.reloc_offset = lum->u.filter.reloc_offset; | |
3f6fd224 | 806 | bytecode->bc.seqnum = lum->u.filter.seqnum; |
cd54f6d9 | 807 | if (ops->cmd) { |
2d78951a | 808 | ret = ops->cmd(lum->handle, lum->cmd, |
cd54f6d9 | 809 | (unsigned long) bytecode, |
f59ed768 | 810 | &args, sock_info); |
cd54f6d9 MD |
811 | if (ret) { |
812 | free(bytecode); | |
813 | } | |
814 | /* don't free bytecode if everything went fine. */ | |
815 | } else { | |
2d78951a | 816 | ret = -ENOSYS; |
cd54f6d9 MD |
817 | free(bytecode); |
818 | } | |
2d78951a MD |
819 | break; |
820 | } | |
86e36163 JI |
821 | case LTTNG_UST_EXCLUSION: |
822 | { | |
823 | /* Receive exclusion names */ | |
824 | struct lttng_ust_excluder_node *node; | |
825 | unsigned int count; | |
826 | ||
827 | count = lum->u.exclusion.count; | |
828 | if (count == 0) { | |
829 | /* There are no names to read */ | |
830 | ret = 0; | |
831 | goto error; | |
832 | } | |
833 | node = zmalloc(sizeof(*node) + | |
834 | count * LTTNG_UST_SYM_NAME_LEN); | |
835 | if (!node) { | |
836 | ret = -ENOMEM; | |
837 | goto error; | |
838 | } | |
839 | node->excluder.count = count; | |
840 | len = ustcomm_recv_unix_sock(sock, node->excluder.names, | |
841 | count * LTTNG_UST_SYM_NAME_LEN); | |
842 | switch (len) { | |
843 | case 0: /* orderly shutdown */ | |
844 | ret = 0; | |
845 | free(node); | |
846 | goto error; | |
847 | default: | |
848 | if (len == count * LTTNG_UST_SYM_NAME_LEN) { | |
849 | DBG("Exclusion data received"); | |
850 | break; | |
851 | } else if (len < 0) { | |
852 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
853 | if (len == -ECONNRESET) { | |
854 | ERR("%s remote end closed connection", sock_info->name); | |
855 | ret = len; | |
856 | free(node); | |
857 | goto error; | |
858 | } | |
859 | ret = len; | |
860 | free(node); | |
0dafcd63 | 861 | goto error; |
86e36163 JI |
862 | } else { |
863 | DBG("Incorrect exclusion data message size: %zd", len); | |
864 | ret = -EINVAL; | |
865 | free(node); | |
0dafcd63 | 866 | goto error; |
86e36163 JI |
867 | } |
868 | } | |
869 | if (ops->cmd) { | |
870 | ret = ops->cmd(lum->handle, lum->cmd, | |
871 | (unsigned long) node, | |
872 | &args, sock_info); | |
873 | if (ret) { | |
874 | free(node); | |
875 | } | |
876 | /* Don't free exclusion data if everything went fine. */ | |
877 | } else { | |
878 | ret = -ENOSYS; | |
879 | free(node); | |
880 | } | |
881 | break; | |
882 | } | |
74d81a6c MD |
883 | case LTTNG_UST_CHANNEL: |
884 | { | |
885 | void *chan_data; | |
ff0f5728 | 886 | int wakeup_fd; |
74d81a6c MD |
887 | |
888 | len = ustcomm_recv_channel_from_sessiond(sock, | |
ff0f5728 MD |
889 | &chan_data, lum->u.channel.len, |
890 | &wakeup_fd); | |
74d81a6c MD |
891 | switch (len) { |
892 | case 0: /* orderly shutdown */ | |
893 | ret = 0; | |
894 | goto error; | |
895 | default: | |
896 | if (len == lum->u.channel.len) { | |
897 | DBG("channel data received"); | |
898 | break; | |
899 | } else if (len < 0) { | |
900 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
901 | if (len == -ECONNRESET) { | |
902 | ERR("%s remote end closed connection", sock_info->name); | |
903 | ret = len; | |
904 | goto error; | |
905 | } | |
906 | ret = len; | |
0dafcd63 | 907 | goto error; |
74d81a6c MD |
908 | } else { |
909 | DBG("incorrect channel data message size: %zd", len); | |
910 | ret = -EINVAL; | |
0dafcd63 | 911 | goto error; |
74d81a6c MD |
912 | } |
913 | } | |
914 | args.channel.chan_data = chan_data; | |
ff0f5728 | 915 | args.channel.wakeup_fd = wakeup_fd; |
74d81a6c MD |
916 | if (ops->cmd) |
917 | ret = ops->cmd(lum->handle, lum->cmd, | |
918 | (unsigned long) &lum->u, | |
919 | &args, sock_info); | |
920 | else | |
921 | ret = -ENOSYS; | |
922 | break; | |
923 | } | |
924 | case LTTNG_UST_STREAM: | |
925 | { | |
926 | /* Receive shm_fd, wakeup_fd */ | |
927 | ret = ustcomm_recv_stream_from_sessiond(sock, | |
729df81e | 928 | NULL, |
74d81a6c MD |
929 | &args.stream.shm_fd, |
930 | &args.stream.wakeup_fd); | |
931 | if (ret) { | |
0dafcd63 | 932 | goto error; |
74d81a6c | 933 | } |
cf4dd19d | 934 | |
74d81a6c MD |
935 | if (ops->cmd) |
936 | ret = ops->cmd(lum->handle, lum->cmd, | |
937 | (unsigned long) &lum->u, | |
938 | &args, sock_info); | |
939 | else | |
940 | ret = -ENOSYS; | |
941 | break; | |
942 | } | |
8e696cfa MD |
943 | case LTTNG_UST_CONTEXT: |
944 | switch (lum->u.context.ctx) { | |
945 | case LTTNG_UST_CONTEXT_APP_CONTEXT: | |
946 | { | |
947 | char *p; | |
948 | size_t ctxlen, recvlen; | |
949 | ||
950 | ctxlen = strlen("$app.") + lum->u.context.u.app_ctx.provider_name_len - 1 | |
951 | + strlen(":") + lum->u.context.u.app_ctx.ctx_name_len; | |
952 | if (ctxlen >= LTTNG_UST_SYM_NAME_LEN) { | |
953 | ERR("Application context string length size is too large: %zu bytes", | |
954 | ctxlen); | |
955 | ret = -EINVAL; | |
956 | goto error; | |
957 | } | |
958 | strcpy(ctxstr, "$app."); | |
959 | p = &ctxstr[strlen("$app.")]; | |
960 | recvlen = ctxlen - strlen("$app."); | |
961 | len = ustcomm_recv_unix_sock(sock, p, recvlen); | |
962 | switch (len) { | |
963 | case 0: /* orderly shutdown */ | |
964 | ret = 0; | |
965 | goto error; | |
966 | default: | |
967 | if (len == recvlen) { | |
968 | DBG("app context data received"); | |
969 | break; | |
970 | } else if (len < 0) { | |
971 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
972 | if (len == -ECONNRESET) { | |
973 | ERR("%s remote end closed connection", sock_info->name); | |
974 | ret = len; | |
975 | goto error; | |
976 | } | |
977 | ret = len; | |
978 | goto error; | |
979 | } else { | |
980 | DBG("incorrect app context data message size: %zd", len); | |
981 | ret = -EINVAL; | |
982 | goto error; | |
983 | } | |
984 | } | |
985 | /* Put : between provider and ctxname. */ | |
986 | p[lum->u.context.u.app_ctx.provider_name_len - 1] = ':'; | |
987 | args.app_context.ctxname = ctxstr; | |
988 | break; | |
989 | } | |
990 | default: | |
991 | break; | |
992 | } | |
993 | if (ops->cmd) { | |
994 | ret = ops->cmd(lum->handle, lum->cmd, | |
995 | (unsigned long) &lum->u, | |
996 | &args, sock_info); | |
997 | } else { | |
998 | ret = -ENOSYS; | |
999 | } | |
1000 | break; | |
d9e99d10 | 1001 | default: |
46050b1a MD |
1002 | if (ops->cmd) |
1003 | ret = ops->cmd(lum->handle, lum->cmd, | |
ef9ff354 | 1004 | (unsigned long) &lum->u, |
f59ed768 | 1005 | &args, sock_info); |
46050b1a MD |
1006 | else |
1007 | ret = -ENOSYS; | |
1008 | break; | |
d9e99d10 | 1009 | } |
46050b1a | 1010 | |
46050b1a MD |
1011 | lur.handle = lum->handle; |
1012 | lur.cmd = lum->cmd; | |
1013 | lur.ret_val = ret; | |
1014 | if (ret >= 0) { | |
7bc53e94 | 1015 | lur.ret_code = LTTNG_UST_OK; |
46050b1a | 1016 | } else { |
7bc53e94 MD |
1017 | /* |
1018 | * Use -LTTNG_UST_ERR as wildcard for UST internal | |
1019 | * error that are not caused by the transport, except if | |
1020 | * we already have a more precise error message to | |
1021 | * report. | |
1022 | */ | |
64b2564e DG |
1023 | if (ret > -LTTNG_UST_ERR) { |
1024 | /* Translate code to UST error. */ | |
1025 | switch (ret) { | |
1026 | case -EEXIST: | |
1027 | lur.ret_code = -LTTNG_UST_ERR_EXIST; | |
1028 | break; | |
1029 | case -EINVAL: | |
1030 | lur.ret_code = -LTTNG_UST_ERR_INVAL; | |
1031 | break; | |
1032 | case -ENOENT: | |
1033 | lur.ret_code = -LTTNG_UST_ERR_NOENT; | |
1034 | break; | |
1035 | case -EPERM: | |
1036 | lur.ret_code = -LTTNG_UST_ERR_PERM; | |
1037 | break; | |
1038 | case -ENOSYS: | |
1039 | lur.ret_code = -LTTNG_UST_ERR_NOSYS; | |
1040 | break; | |
1041 | default: | |
1042 | lur.ret_code = -LTTNG_UST_ERR; | |
1043 | break; | |
1044 | } | |
1045 | } else { | |
7bc53e94 | 1046 | lur.ret_code = ret; |
64b2564e | 1047 | } |
46050b1a | 1048 | } |
e6ea14c5 MD |
1049 | if (ret >= 0) { |
1050 | switch (lum->cmd) { | |
e6ea14c5 MD |
1051 | case LTTNG_UST_TRACER_VERSION: |
1052 | lur.u.version = lum->u.version; | |
1053 | break; | |
1054 | case LTTNG_UST_TRACEPOINT_LIST_GET: | |
1055 | memcpy(&lur.u.tracepoint, &lum->u.tracepoint, sizeof(lur.u.tracepoint)); | |
1056 | break; | |
1057 | } | |
381c0f1e | 1058 | } |
74d81a6c | 1059 | DBG("Return value: %d", lur.ret_val); |
4c62d8d1 MD |
1060 | |
1061 | ust_unlock(); | |
1062 | ||
1063 | /* | |
1064 | * Performed delayed statedump operations outside of the UST | |
1065 | * lock. We need to take the dynamic loader lock before we take | |
1066 | * the UST lock internally within handle_pending_statedump(). | |
1067 | */ | |
1068 | handle_pending_statedump(sock_info); | |
1069 | ||
1070 | if (ust_lock()) { | |
1071 | ret = -LTTNG_UST_ERR_EXITING; | |
1072 | goto error; | |
1073 | } | |
1074 | ||
46050b1a | 1075 | ret = send_reply(sock, &lur); |
193183fb | 1076 | if (ret < 0) { |
7bc53e94 | 1077 | DBG("error sending reply"); |
193183fb MD |
1078 | goto error; |
1079 | } | |
46050b1a | 1080 | |
40003310 MD |
1081 | /* |
1082 | * LTTNG_UST_TRACEPOINT_FIELD_LIST_GET needs to send the field | |
1083 | * after the reply. | |
1084 | */ | |
7bc53e94 | 1085 | if (lur.ret_code == LTTNG_UST_OK) { |
40003310 MD |
1086 | switch (lum->cmd) { |
1087 | case LTTNG_UST_TRACEPOINT_FIELD_LIST_GET: | |
1088 | len = ustcomm_send_unix_sock(sock, | |
1089 | &args.field_list.entry, | |
1090 | sizeof(args.field_list.entry)); | |
7bc53e94 MD |
1091 | if (len < 0) { |
1092 | ret = len; | |
1093 | goto error; | |
1094 | } | |
40003310 | 1095 | if (len != sizeof(args.field_list.entry)) { |
7bc53e94 | 1096 | ret = -EINVAL; |
40003310 MD |
1097 | goto error; |
1098 | } | |
1099 | } | |
1100 | } | |
ef9ff354 | 1101 | |
381c0f1e | 1102 | error: |
17dfb34b | 1103 | ust_unlock(); |
d9e99d10 | 1104 | |
37dddb65 | 1105 | return ret; |
246be17e PW |
1106 | } |
1107 | ||
46050b1a | 1108 | static |
efe0de09 | 1109 | void cleanup_sock_info(struct sock_info *sock_info, int exiting) |
46050b1a MD |
1110 | { |
1111 | int ret; | |
1112 | ||
5b14aab3 MD |
1113 | if (sock_info->root_handle != -1) { |
1114 | ret = lttng_ust_objd_unref(sock_info->root_handle, 1); | |
1115 | if (ret) { | |
1116 | ERR("Error unref root handle"); | |
1117 | } | |
1118 | sock_info->root_handle = -1; | |
1119 | } | |
a4416702 GAPG |
1120 | sock_info->registration_done = 0; |
1121 | sock_info->initial_statedump_done = 0; | |
5b14aab3 MD |
1122 | |
1123 | /* | |
1124 | * wait_shm_mmap, socket and notify socket are used by listener | |
1125 | * threads outside of the ust lock, so we cannot tear them down | |
1126 | * ourselves, because we cannot join on these threads. Leave | |
1127 | * responsibility of cleaning up these resources to the OS | |
1128 | * process exit. | |
1129 | */ | |
1130 | if (exiting) | |
1131 | return; | |
1132 | ||
46050b1a | 1133 | if (sock_info->socket != -1) { |
e6973a89 | 1134 | ret = ustcomm_close_unix_sock(sock_info->socket); |
46050b1a | 1135 | if (ret) { |
32ce8569 | 1136 | ERR("Error closing ust cmd socket"); |
46050b1a MD |
1137 | } |
1138 | sock_info->socket = -1; | |
1139 | } | |
32ce8569 MD |
1140 | if (sock_info->notify_socket != -1) { |
1141 | ret = ustcomm_close_unix_sock(sock_info->notify_socket); | |
1142 | if (ret) { | |
1143 | ERR("Error closing ust notify socket"); | |
1144 | } | |
1145 | sock_info->notify_socket = -1; | |
1146 | } | |
5b14aab3 | 1147 | if (sock_info->wait_shm_mmap) { |
172d6b68 MD |
1148 | long page_size; |
1149 | ||
1150 | page_size = sysconf(_SC_PAGE_SIZE); | |
2657d1ba MD |
1151 | if (page_size <= 0) { |
1152 | if (!page_size) { | |
1153 | errno = EINVAL; | |
1154 | } | |
1155 | PERROR("Error in sysconf(_SC_PAGE_SIZE)"); | |
1156 | } else { | |
172d6b68 MD |
1157 | ret = munmap(sock_info->wait_shm_mmap, page_size); |
1158 | if (ret) { | |
1159 | ERR("Error unmapping wait shm"); | |
1160 | } | |
7fc90dca MD |
1161 | } |
1162 | sock_info->wait_shm_mmap = NULL; | |
1163 | } | |
1164 | } | |
1165 | ||
58d4b2a2 | 1166 | /* |
33bbeb90 MD |
1167 | * Using fork to set umask in the child process (not multi-thread safe). |
1168 | * We deal with the shm_open vs ftruncate race (happening when the | |
1169 | * sessiond owns the shm and does not let everybody modify it, to ensure | |
1170 | * safety against shm_unlink) by simply letting the mmap fail and | |
1171 | * retrying after a few seconds. | |
1172 | * For global shm, everybody has rw access to it until the sessiond | |
1173 | * starts. | |
58d4b2a2 | 1174 | */ |
7fc90dca | 1175 | static |
58d4b2a2 | 1176 | int get_wait_shm(struct sock_info *sock_info, size_t mmap_size) |
7fc90dca | 1177 | { |
7fc90dca | 1178 | int wait_shm_fd, ret; |
58d4b2a2 | 1179 | pid_t pid; |
44e073f5 | 1180 | |
58d4b2a2 | 1181 | /* |
33bbeb90 | 1182 | * Try to open read-only. |
58d4b2a2 | 1183 | */ |
33bbeb90 | 1184 | wait_shm_fd = shm_open(sock_info->wait_shm_path, O_RDONLY, 0); |
58d4b2a2 | 1185 | if (wait_shm_fd >= 0) { |
7aa76730 MD |
1186 | int32_t tmp_read; |
1187 | ssize_t len; | |
1188 | size_t bytes_read = 0; | |
1189 | ||
1190 | /* | |
1191 | * Try to read the fd. If unable to do so, try opening | |
1192 | * it in write mode. | |
1193 | */ | |
1194 | do { | |
1195 | len = read(wait_shm_fd, | |
1196 | &((char *) &tmp_read)[bytes_read], | |
1197 | sizeof(tmp_read) - bytes_read); | |
1198 | if (len > 0) { | |
1199 | bytes_read += len; | |
1200 | } | |
1201 | } while ((len < 0 && errno == EINTR) | |
1202 | || (len > 0 && bytes_read < sizeof(tmp_read))); | |
1203 | if (bytes_read != sizeof(tmp_read)) { | |
1204 | ret = close(wait_shm_fd); | |
1205 | if (ret) { | |
1206 | ERR("close wait_shm_fd"); | |
1207 | } | |
1208 | goto open_write; | |
1209 | } | |
58d4b2a2 MD |
1210 | goto end; |
1211 | } else if (wait_shm_fd < 0 && errno != ENOENT) { | |
1212 | /* | |
33bbeb90 MD |
1213 | * Real-only open did not work, and it's not because the |
1214 | * entry was not present. It's a failure that prohibits | |
1215 | * using shm. | |
58d4b2a2 | 1216 | */ |
7fc90dca | 1217 | ERR("Error opening shm %s", sock_info->wait_shm_path); |
58d4b2a2 | 1218 | goto end; |
7fc90dca | 1219 | } |
7aa76730 MD |
1220 | |
1221 | open_write: | |
7fc90dca | 1222 | /* |
7aa76730 MD |
1223 | * If the open failed because the file did not exist, or because |
1224 | * the file was not truncated yet, try creating it ourself. | |
7fc90dca | 1225 | */ |
8c90a710 | 1226 | URCU_TLS(lttng_ust_nest_count)++; |
58d4b2a2 | 1227 | pid = fork(); |
8c90a710 | 1228 | URCU_TLS(lttng_ust_nest_count)--; |
58d4b2a2 MD |
1229 | if (pid > 0) { |
1230 | int status; | |
1231 | ||
1232 | /* | |
1233 | * Parent: wait for child to return, in which case the | |
1234 | * shared memory map will have been created. | |
1235 | */ | |
1236 | pid = wait(&status); | |
b7d3cb32 | 1237 | if (pid < 0 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) { |
58d4b2a2 MD |
1238 | wait_shm_fd = -1; |
1239 | goto end; | |
7fc90dca | 1240 | } |
58d4b2a2 MD |
1241 | /* |
1242 | * Try to open read-only again after creation. | |
1243 | */ | |
33bbeb90 | 1244 | wait_shm_fd = shm_open(sock_info->wait_shm_path, O_RDONLY, 0); |
58d4b2a2 MD |
1245 | if (wait_shm_fd < 0) { |
1246 | /* | |
1247 | * Real-only open did not work. It's a failure | |
1248 | * that prohibits using shm. | |
1249 | */ | |
1250 | ERR("Error opening shm %s", sock_info->wait_shm_path); | |
1251 | goto end; | |
1252 | } | |
1253 | goto end; | |
1254 | } else if (pid == 0) { | |
1255 | int create_mode; | |
1256 | ||
1257 | /* Child */ | |
33bbeb90 | 1258 | create_mode = S_IRUSR | S_IWUSR | S_IRGRP; |
58d4b2a2 | 1259 | if (sock_info->global) |
33bbeb90 | 1260 | create_mode |= S_IROTH | S_IWGRP | S_IWOTH; |
58d4b2a2 MD |
1261 | /* |
1262 | * We're alone in a child process, so we can modify the | |
1263 | * process-wide umask. | |
1264 | */ | |
33bbeb90 | 1265 | umask(~create_mode); |
58d4b2a2 | 1266 | /* |
33bbeb90 MD |
1267 | * Try creating shm (or get rw access). |
1268 | * We don't do an exclusive open, because we allow other | |
1269 | * processes to create+ftruncate it concurrently. | |
58d4b2a2 MD |
1270 | */ |
1271 | wait_shm_fd = shm_open(sock_info->wait_shm_path, | |
1272 | O_RDWR | O_CREAT, create_mode); | |
1273 | if (wait_shm_fd >= 0) { | |
1274 | ret = ftruncate(wait_shm_fd, mmap_size); | |
1275 | if (ret) { | |
1276 | PERROR("ftruncate"); | |
b0c1425d | 1277 | _exit(EXIT_FAILURE); |
58d4b2a2 | 1278 | } |
b0c1425d | 1279 | _exit(EXIT_SUCCESS); |
58d4b2a2 | 1280 | } |
33bbeb90 MD |
1281 | /* |
1282 | * For local shm, we need to have rw access to accept | |
1283 | * opening it: this means the local sessiond will be | |
1284 | * able to wake us up. For global shm, we open it even | |
1285 | * if rw access is not granted, because the root.root | |
1286 | * sessiond will be able to override all rights and wake | |
1287 | * us up. | |
1288 | */ | |
1289 | if (!sock_info->global && errno != EACCES) { | |
58d4b2a2 | 1290 | ERR("Error opening shm %s", sock_info->wait_shm_path); |
5d3bc5ed | 1291 | _exit(EXIT_FAILURE); |
58d4b2a2 MD |
1292 | } |
1293 | /* | |
33bbeb90 MD |
1294 | * The shm exists, but we cannot open it RW. Report |
1295 | * success. | |
58d4b2a2 | 1296 | */ |
5d3bc5ed | 1297 | _exit(EXIT_SUCCESS); |
58d4b2a2 MD |
1298 | } else { |
1299 | return -1; | |
7fc90dca | 1300 | } |
58d4b2a2 | 1301 | end: |
33bbeb90 MD |
1302 | if (wait_shm_fd >= 0 && !sock_info->global) { |
1303 | struct stat statbuf; | |
1304 | ||
1305 | /* | |
1306 | * Ensure that our user is the owner of the shm file for | |
1307 | * local shm. If we do not own the file, it means our | |
1308 | * sessiond will not have access to wake us up (there is | |
1309 | * probably a rogue process trying to fake our | |
1310 | * sessiond). Fallback to polling method in this case. | |
1311 | */ | |
1312 | ret = fstat(wait_shm_fd, &statbuf); | |
1313 | if (ret) { | |
1314 | PERROR("fstat"); | |
1315 | goto error_close; | |
1316 | } | |
1317 | if (statbuf.st_uid != getuid()) | |
1318 | goto error_close; | |
1319 | } | |
58d4b2a2 | 1320 | return wait_shm_fd; |
33bbeb90 MD |
1321 | |
1322 | error_close: | |
1323 | ret = close(wait_shm_fd); | |
1324 | if (ret) { | |
1325 | PERROR("Error closing fd"); | |
1326 | } | |
1327 | return -1; | |
58d4b2a2 MD |
1328 | } |
1329 | ||
1330 | static | |
1331 | char *get_map_shm(struct sock_info *sock_info) | |
1332 | { | |
172d6b68 | 1333 | long page_size; |
58d4b2a2 MD |
1334 | int wait_shm_fd, ret; |
1335 | char *wait_shm_mmap; | |
1336 | ||
172d6b68 | 1337 | page_size = sysconf(_SC_PAGE_SIZE); |
2657d1ba MD |
1338 | if (page_size <= 0) { |
1339 | if (!page_size) { | |
1340 | errno = EINVAL; | |
1341 | } | |
1342 | PERROR("Error in sysconf(_SC_PAGE_SIZE)"); | |
172d6b68 MD |
1343 | goto error; |
1344 | } | |
1345 | ||
6548fca4 | 1346 | lttng_ust_lock_fd_tracker(); |
172d6b68 | 1347 | wait_shm_fd = get_wait_shm(sock_info, page_size); |
58d4b2a2 | 1348 | if (wait_shm_fd < 0) { |
6548fca4 | 1349 | lttng_ust_unlock_fd_tracker(); |
58d4b2a2 | 1350 | goto error; |
44e073f5 | 1351 | } |
0dd6b494 JR |
1352 | |
1353 | ret = lttng_ust_add_fd_to_tracker(wait_shm_fd); | |
1354 | if (ret < 0) { | |
1355 | ret = close(wait_shm_fd); | |
1356 | if (!ret) { | |
1357 | PERROR("Error closing fd"); | |
1358 | } | |
1359 | lttng_ust_unlock_fd_tracker(); | |
1360 | goto error; | |
1361 | } | |
1362 | ||
1363 | wait_shm_fd = ret; | |
6548fca4 MD |
1364 | lttng_ust_unlock_fd_tracker(); |
1365 | ||
172d6b68 | 1366 | wait_shm_mmap = mmap(NULL, page_size, PROT_READ, |
7fc90dca | 1367 | MAP_SHARED, wait_shm_fd, 0); |
6548fca4 | 1368 | |
7fc90dca | 1369 | /* close shm fd immediately after taking the mmap reference */ |
6548fca4 | 1370 | lttng_ust_lock_fd_tracker(); |
7fc90dca | 1371 | ret = close(wait_shm_fd); |
6548fca4 MD |
1372 | if (!ret) { |
1373 | lttng_ust_delete_fd_from_tracker(wait_shm_fd); | |
1374 | } else { | |
33bbeb90 MD |
1375 | PERROR("Error closing fd"); |
1376 | } | |
6548fca4 MD |
1377 | lttng_ust_unlock_fd_tracker(); |
1378 | ||
33bbeb90 MD |
1379 | if (wait_shm_mmap == MAP_FAILED) { |
1380 | DBG("mmap error (can be caused by race with sessiond). Fallback to poll mode."); | |
1381 | goto error; | |
7fc90dca MD |
1382 | } |
1383 | return wait_shm_mmap; | |
1384 | ||
1385 | error: | |
1386 | return NULL; | |
1387 | } | |
1388 | ||
1389 | static | |
1390 | void wait_for_sessiond(struct sock_info *sock_info) | |
1391 | { | |
ef4a06d9 | 1392 | /* Use ust_lock to check if we should quit. */ |
3327ac33 | 1393 | if (ust_lock()) { |
7fc90dca MD |
1394 | goto quit; |
1395 | } | |
37ed587a MD |
1396 | if (wait_poll_fallback) { |
1397 | goto error; | |
1398 | } | |
7fc90dca MD |
1399 | ust_unlock(); |
1400 | ||
ef4a06d9 JR |
1401 | assert(sock_info->wait_shm_mmap); |
1402 | ||
7fc90dca | 1403 | DBG("Waiting for %s apps sessiond", sock_info->name); |
80e2814b | 1404 | /* Wait for futex wakeup */ |
ee7fcec8 MD |
1405 | if (uatomic_read((int32_t *) sock_info->wait_shm_mmap)) |
1406 | goto end_wait; | |
1407 | ||
1408 | while (futex_async((int32_t *) sock_info->wait_shm_mmap, | |
1409 | FUTEX_WAIT, 0, NULL, NULL, 0)) { | |
1410 | switch (errno) { | |
1411 | case EWOULDBLOCK: | |
1412 | /* Value already changed. */ | |
1413 | goto end_wait; | |
1414 | case EINTR: | |
1415 | /* Retry if interrupted by signal. */ | |
1416 | break; /* Get out of switch. */ | |
1417 | case EFAULT: | |
1418 | wait_poll_fallback = 1; | |
1419 | DBG( | |
37ed587a MD |
1420 | "Linux kernels 2.6.33 to 3.0 (with the exception of stable versions) " |
1421 | "do not support FUTEX_WAKE on read-only memory mappings correctly. " | |
1422 | "Please upgrade your kernel " | |
1423 | "(fix is commit 9ea71503a8ed9184d2d0b8ccc4d269d05f7940ae in Linux kernel " | |
1424 | "mainline). LTTng-UST will use polling mode fallback."); | |
ee7fcec8 MD |
1425 | if (ust_debug()) |
1426 | PERROR("futex"); | |
1427 | goto end_wait; | |
80e2814b MD |
1428 | } |
1429 | } | |
ee7fcec8 | 1430 | end_wait: |
7fc90dca MD |
1431 | return; |
1432 | ||
1433 | quit: | |
1434 | ust_unlock(); | |
1435 | return; | |
1436 | ||
1437 | error: | |
1438 | ust_unlock(); | |
7fc90dca | 1439 | return; |
46050b1a MD |
1440 | } |
1441 | ||
1ea11eab MD |
1442 | /* |
1443 | * This thread does not allocate any resource, except within | |
1444 | * handle_message, within mutex protection. This mutex protects against | |
1445 | * fork and exit. | |
98bf993f | 1446 | * The other moment it allocates resources is at socket connection, which |
1ea11eab MD |
1447 | * is also protected by the mutex. |
1448 | */ | |
d9e99d10 MD |
1449 | static |
1450 | void *ust_listener_thread(void *arg) | |
1451 | { | |
1ea11eab | 1452 | struct sock_info *sock_info = arg; |
0dd6b494 | 1453 | int sock, ret, prev_connect_failed = 0, has_waited = 0, fd; |
ff517991 | 1454 | long timeout; |
d9e99d10 | 1455 | |
c362addf | 1456 | lttng_ust_fixup_tls(); |
01f0e40c RB |
1457 | /* |
1458 | * If available, add '-ust' to the end of this thread's | |
1459 | * process name | |
1460 | */ | |
1461 | ret = lttng_ust_setustprocname(); | |
1462 | if (ret) { | |
1463 | ERR("Unable to set UST process name"); | |
1464 | } | |
1465 | ||
9eb62b9c MD |
1466 | /* Restart trying to connect to the session daemon */ |
1467 | restart: | |
c0eedf81 MD |
1468 | if (prev_connect_failed) { |
1469 | /* Wait for sessiond availability with pipe */ | |
1470 | wait_for_sessiond(sock_info); | |
1471 | if (has_waited) { | |
1472 | has_waited = 0; | |
1473 | /* | |
1474 | * Sleep for 5 seconds before retrying after a | |
1475 | * sequence of failure / wait / failure. This | |
1476 | * deals with a killed or broken session daemon. | |
1477 | */ | |
1478 | sleep(5); | |
eacc4aa4 MD |
1479 | } else { |
1480 | has_waited = 1; | |
c0eedf81 | 1481 | } |
c0eedf81 MD |
1482 | prev_connect_failed = 0; |
1483 | } | |
9eb62b9c | 1484 | |
0818d379 JR |
1485 | if (ust_lock()) { |
1486 | goto quit; | |
1487 | } | |
1488 | ||
1ea11eab | 1489 | if (sock_info->socket != -1) { |
6548fca4 | 1490 | /* FD tracker is updated by ustcomm_close_unix_sock() */ |
e6973a89 | 1491 | ret = ustcomm_close_unix_sock(sock_info->socket); |
1ea11eab | 1492 | if (ret) { |
32ce8569 MD |
1493 | ERR("Error closing %s ust cmd socket", |
1494 | sock_info->name); | |
1ea11eab MD |
1495 | } |
1496 | sock_info->socket = -1; | |
1497 | } | |
32ce8569 | 1498 | if (sock_info->notify_socket != -1) { |
6548fca4 | 1499 | /* FD tracker is updated by ustcomm_close_unix_sock() */ |
32ce8569 MD |
1500 | ret = ustcomm_close_unix_sock(sock_info->notify_socket); |
1501 | if (ret) { | |
1502 | ERR("Error closing %s ust notify socket", | |
1503 | sock_info->name); | |
1504 | } | |
1505 | sock_info->notify_socket = -1; | |
1506 | } | |
46050b1a | 1507 | |
6548fca4 | 1508 | |
321f2351 MD |
1509 | /* |
1510 | * Register. We need to perform both connect and sending | |
1511 | * registration message before doing the next connect otherwise | |
1512 | * we may reach unix socket connect queue max limits and block | |
1513 | * on the 2nd connect while the session daemon is awaiting the | |
1514 | * first connect registration message. | |
1515 | */ | |
1516 | /* Connect cmd socket */ | |
6548fca4 | 1517 | lttng_ust_lock_fd_tracker(); |
451d66b2 MD |
1518 | ret = ustcomm_connect_unix_sock(sock_info->sock_path, |
1519 | get_connect_sock_timeout()); | |
321f2351 | 1520 | if (ret < 0) { |
6548fca4 | 1521 | lttng_ust_unlock_fd_tracker(); |
321f2351 MD |
1522 | DBG("Info: sessiond not accepting connections to %s apps socket", sock_info->name); |
1523 | prev_connect_failed = 1; | |
5b14aab3 | 1524 | |
e3426ddc | 1525 | /* |
321f2351 MD |
1526 | * If we cannot find the sessiond daemon, don't delay |
1527 | * constructor execution. | |
e3426ddc | 1528 | */ |
a4416702 | 1529 | ret = handle_register_failed(sock_info); |
321f2351 MD |
1530 | assert(!ret); |
1531 | ust_unlock(); | |
1532 | goto restart; | |
27fe9f21 | 1533 | } |
0dd6b494 JR |
1534 | fd = ret; |
1535 | ret = lttng_ust_add_fd_to_tracker(fd); | |
1536 | if (ret < 0) { | |
1537 | ret = close(fd); | |
1538 | if (ret) { | |
1539 | PERROR("close on sock_info->socket"); | |
1540 | } | |
1541 | ret = -1; | |
1542 | lttng_ust_unlock_fd_tracker(); | |
1543 | ust_unlock(); | |
1544 | goto quit; | |
1545 | } | |
1546 | ||
321f2351 | 1547 | sock_info->socket = ret; |
0dd6b494 | 1548 | lttng_ust_unlock_fd_tracker(); |
27fe9f21 | 1549 | |
6548fca4 MD |
1550 | ust_unlock(); |
1551 | /* | |
1552 | * Unlock/relock ust lock because connect is blocking (with | |
1553 | * timeout). Don't delay constructors on the ust lock for too | |
1554 | * long. | |
1555 | */ | |
3327ac33 | 1556 | if (ust_lock()) { |
5b14aab3 MD |
1557 | goto quit; |
1558 | } | |
1559 | ||
46050b1a MD |
1560 | /* |
1561 | * Create only one root handle per listener thread for the whole | |
f59ed768 MD |
1562 | * process lifetime, so we ensure we get ID which is statically |
1563 | * assigned to the root handle. | |
46050b1a MD |
1564 | */ |
1565 | if (sock_info->root_handle == -1) { | |
1566 | ret = lttng_abi_create_root_handle(); | |
a51070bb | 1567 | if (ret < 0) { |
46050b1a | 1568 | ERR("Error creating root handle"); |
46050b1a MD |
1569 | goto quit; |
1570 | } | |
1571 | sock_info->root_handle = ret; | |
9eb62b9c | 1572 | } |
1ea11eab | 1573 | |
32ce8569 | 1574 | ret = register_to_sessiond(sock_info->socket, USTCTL_SOCKET_CMD); |
9eb62b9c | 1575 | if (ret < 0) { |
32ce8569 MD |
1576 | ERR("Error registering to %s ust cmd socket", |
1577 | sock_info->name); | |
c0eedf81 | 1578 | prev_connect_failed = 1; |
11ff9c7d MD |
1579 | /* |
1580 | * If we cannot register to the sessiond daemon, don't | |
1581 | * delay constructor execution. | |
1582 | */ | |
a4416702 | 1583 | ret = handle_register_failed(sock_info); |
11ff9c7d | 1584 | assert(!ret); |
17dfb34b | 1585 | ust_unlock(); |
9eb62b9c MD |
1586 | goto restart; |
1587 | } | |
321f2351 MD |
1588 | |
1589 | ust_unlock(); | |
6548fca4 MD |
1590 | /* |
1591 | * Unlock/relock ust lock because connect is blocking (with | |
1592 | * timeout). Don't delay constructors on the ust lock for too | |
1593 | * long. | |
1594 | */ | |
1595 | if (ust_lock()) { | |
1596 | goto quit; | |
1597 | } | |
321f2351 MD |
1598 | |
1599 | /* Connect notify socket */ | |
6548fca4 | 1600 | lttng_ust_lock_fd_tracker(); |
451d66b2 MD |
1601 | ret = ustcomm_connect_unix_sock(sock_info->sock_path, |
1602 | get_connect_sock_timeout()); | |
321f2351 | 1603 | if (ret < 0) { |
6548fca4 | 1604 | lttng_ust_unlock_fd_tracker(); |
321f2351 MD |
1605 | DBG("Info: sessiond not accepting connections to %s apps socket", sock_info->name); |
1606 | prev_connect_failed = 1; | |
1607 | ||
321f2351 MD |
1608 | /* |
1609 | * If we cannot find the sessiond daemon, don't delay | |
1610 | * constructor execution. | |
1611 | */ | |
a4416702 | 1612 | ret = handle_register_failed(sock_info); |
321f2351 MD |
1613 | assert(!ret); |
1614 | ust_unlock(); | |
1615 | goto restart; | |
1616 | } | |
0dd6b494 JR |
1617 | |
1618 | fd = ret; | |
1619 | ret = lttng_ust_add_fd_to_tracker(fd); | |
1620 | if (ret < 0) { | |
1621 | ret = close(fd); | |
1622 | if (ret) { | |
1623 | PERROR("close on sock_info->notify_socket"); | |
1624 | } | |
1625 | ret = -1; | |
1626 | lttng_ust_unlock_fd_tracker(); | |
1627 | ust_unlock(); | |
1628 | goto quit; | |
1629 | } | |
1630 | ||
321f2351 | 1631 | sock_info->notify_socket = ret; |
0dd6b494 | 1632 | lttng_ust_unlock_fd_tracker(); |
321f2351 | 1633 | |
6548fca4 MD |
1634 | ust_unlock(); |
1635 | /* | |
1636 | * Unlock/relock ust lock because connect is blocking (with | |
1637 | * timeout). Don't delay constructors on the ust lock for too | |
1638 | * long. | |
1639 | */ | |
1640 | if (ust_lock()) { | |
1641 | goto quit; | |
1642 | } | |
1643 | ||
321f2351 MD |
1644 | timeout = get_notify_sock_timeout(); |
1645 | if (timeout >= 0) { | |
1646 | /* | |
1647 | * Give at least 10ms to sessiond to reply to | |
1648 | * notifications. | |
1649 | */ | |
1650 | if (timeout < 10) | |
1651 | timeout = 10; | |
1652 | ret = ustcomm_setsockopt_rcv_timeout(sock_info->notify_socket, | |
1653 | timeout); | |
1654 | if (ret < 0) { | |
1655 | WARN("Error setting socket receive timeout"); | |
1656 | } | |
1657 | ret = ustcomm_setsockopt_snd_timeout(sock_info->notify_socket, | |
1658 | timeout); | |
1659 | if (ret < 0) { | |
1660 | WARN("Error setting socket send timeout"); | |
1661 | } | |
1662 | } else if (timeout < -1) { | |
1663 | WARN("Unsupported timeout value %ld", timeout); | |
1664 | } | |
1665 | ||
32ce8569 MD |
1666 | ret = register_to_sessiond(sock_info->notify_socket, |
1667 | USTCTL_SOCKET_NOTIFY); | |
1668 | if (ret < 0) { | |
1669 | ERR("Error registering to %s ust notify socket", | |
1670 | sock_info->name); | |
1671 | prev_connect_failed = 1; | |
1672 | /* | |
1673 | * If we cannot register to the sessiond daemon, don't | |
1674 | * delay constructor execution. | |
1675 | */ | |
a4416702 | 1676 | ret = handle_register_failed(sock_info); |
32ce8569 MD |
1677 | assert(!ret); |
1678 | ust_unlock(); | |
1679 | goto restart; | |
1680 | } | |
1681 | sock = sock_info->socket; | |
1682 | ||
17dfb34b | 1683 | ust_unlock(); |
46050b1a | 1684 | |
d9e99d10 MD |
1685 | for (;;) { |
1686 | ssize_t len; | |
57773204 | 1687 | struct ustcomm_ust_msg lum; |
d9e99d10 | 1688 | |
57773204 | 1689 | len = ustcomm_recv_unix_sock(sock, &lum, sizeof(lum)); |
d9e99d10 MD |
1690 | switch (len) { |
1691 | case 0: /* orderly shutdown */ | |
7dd08bec | 1692 | DBG("%s lttng-sessiond has performed an orderly shutdown", sock_info->name); |
3327ac33 | 1693 | if (ust_lock()) { |
d5e1fea6 MD |
1694 | goto quit; |
1695 | } | |
8236ba10 MD |
1696 | /* |
1697 | * Either sessiond has shutdown or refused us by closing the socket. | |
1698 | * In either case, we don't want to delay construction execution, | |
1699 | * and we need to wait before retry. | |
1700 | */ | |
1701 | prev_connect_failed = 1; | |
1702 | /* | |
1703 | * If we cannot register to the sessiond daemon, don't | |
1704 | * delay constructor execution. | |
1705 | */ | |
a4416702 | 1706 | ret = handle_register_failed(sock_info); |
8236ba10 MD |
1707 | assert(!ret); |
1708 | ust_unlock(); | |
d9e99d10 | 1709 | goto end; |
e7723462 | 1710 | case sizeof(lum): |
74d81a6c | 1711 | print_cmd(lum.cmd, lum.handle); |
11ff9c7d | 1712 | ret = handle_message(sock_info, sock, &lum); |
7bc53e94 | 1713 | if (ret) { |
0dafcd63 MD |
1714 | ERR("Error handling message for %s socket", |
1715 | sock_info->name); | |
1716 | /* | |
1717 | * Close socket if protocol error is | |
1718 | * detected. | |
1719 | */ | |
1720 | goto end; | |
d9e99d10 MD |
1721 | } |
1722 | continue; | |
7bc53e94 MD |
1723 | default: |
1724 | if (len < 0) { | |
1725 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
1726 | } else { | |
1727 | DBG("incorrect message size (%s socket): %zd", sock_info->name, len); | |
1728 | } | |
1729 | if (len == -ECONNRESET) { | |
1730 | DBG("%s remote end closed connection", sock_info->name); | |
d9e99d10 MD |
1731 | goto end; |
1732 | } | |
1733 | goto end; | |
d9e99d10 MD |
1734 | } |
1735 | ||
1736 | } | |
1737 | end: | |
3327ac33 | 1738 | if (ust_lock()) { |
d5e1fea6 MD |
1739 | goto quit; |
1740 | } | |
f59ed768 MD |
1741 | /* Cleanup socket handles before trying to reconnect */ |
1742 | lttng_ust_objd_table_owner_cleanup(sock_info); | |
1743 | ust_unlock(); | |
9eb62b9c | 1744 | goto restart; /* try to reconnect */ |
e33f3265 | 1745 | |
1ea11eab | 1746 | quit: |
e33f3265 | 1747 | ust_unlock(); |
3327ac33 MD |
1748 | |
1749 | pthread_mutex_lock(&ust_exit_mutex); | |
1750 | sock_info->thread_active = 0; | |
1751 | pthread_mutex_unlock(&ust_exit_mutex); | |
d9e99d10 MD |
1752 | return NULL; |
1753 | } | |
1754 | ||
2594a5b4 MD |
1755 | /* |
1756 | * Weak symbol to call when the ust malloc wrapper is not loaded. | |
1757 | */ | |
1758 | __attribute__((weak)) | |
1759 | void lttng_ust_malloc_wrapper_init(void) | |
1760 | { | |
1761 | } | |
1762 | ||
2691221a MD |
1763 | /* |
1764 | * sessiond monitoring thread: monitor presence of global and per-user | |
1765 | * sessiond by polling the application common named pipe. | |
1766 | */ | |
edaa1431 | 1767 | void __attribute__((constructor)) lttng_ust_init(void) |
2691221a | 1768 | { |
11ff9c7d | 1769 | struct timespec constructor_timeout; |
ae6a58bf | 1770 | sigset_t sig_all_blocked, orig_parent_mask; |
1879f67f | 1771 | pthread_attr_t thread_attr; |
cf12a773 | 1772 | int timeout_mode; |
2691221a MD |
1773 | int ret; |
1774 | ||
edaa1431 MD |
1775 | if (uatomic_xchg(&initialized, 1) == 1) |
1776 | return; | |
1777 | ||
eddd8d5d MD |
1778 | /* |
1779 | * Fixup interdependency between TLS fixup mutex (which happens | |
1780 | * to be the dynamic linker mutex) and ust_lock, taken within | |
1781 | * the ust lock. | |
1782 | */ | |
c362addf | 1783 | lttng_ust_fixup_tls(); |
eddd8d5d | 1784 | |
07b57e5e MD |
1785 | lttng_ust_loaded = 1; |
1786 | ||
edaa1431 MD |
1787 | /* |
1788 | * We want precise control over the order in which we construct | |
1789 | * our sub-libraries vs starting to receive commands from | |
1790 | * sessiond (otherwise leading to errors when trying to create | |
1791 | * sessiond before the init functions are completed). | |
1792 | */ | |
2691221a | 1793 | init_usterr(); |
6f626d28 | 1794 | lttng_ust_getenv_init(); /* Needs init_usterr() to be completed. */ |
edaa1431 | 1795 | init_tracepoint(); |
6548fca4 | 1796 | lttng_ust_init_fd_tracker(); |
f9364363 | 1797 | lttng_ust_clock_init(); |
5e1b7b8b | 1798 | lttng_ust_getcpu_init(); |
cf73e0fe | 1799 | lttng_ust_statedump_init(); |
7dd08bec MD |
1800 | lttng_ring_buffer_metadata_client_init(); |
1801 | lttng_ring_buffer_client_overwrite_init(); | |
34a91bdb | 1802 | lttng_ring_buffer_client_overwrite_rt_init(); |
7dd08bec | 1803 | lttng_ring_buffer_client_discard_init(); |
34a91bdb | 1804 | lttng_ring_buffer_client_discard_rt_init(); |
d58d1454 | 1805 | lttng_perf_counter_init(); |
2594a5b4 MD |
1806 | /* |
1807 | * Invoke ust malloc wrapper init before starting other threads. | |
1808 | */ | |
1809 | lttng_ust_malloc_wrapper_init(); | |
2691221a | 1810 | |
ff517991 | 1811 | timeout_mode = get_constructor_timeout(&constructor_timeout); |
11ff9c7d | 1812 | |
9050321d | 1813 | get_allow_blocking(); |
6f97f9c2 | 1814 | |
95259bd0 | 1815 | ret = sem_init(&constructor_wait, 0, 0); |
8aadb54a MD |
1816 | if (ret) { |
1817 | PERROR("sem_init"); | |
1818 | } | |
11ff9c7d | 1819 | |
ef4a06d9 JR |
1820 | ret = setup_global_apps(); |
1821 | if (ret) { | |
1822 | assert(global_apps.allowed == 0); | |
1823 | DBG("global apps setup returned %d", ret); | |
1824 | } | |
1825 | ||
8d20bf54 | 1826 | ret = setup_local_apps(); |
2691221a | 1827 | if (ret) { |
ef4a06d9 | 1828 | assert(local_apps.allowed == 0); |
9ec6895c | 1829 | DBG("local apps setup returned %d", ret); |
2691221a | 1830 | } |
ae6a58bf WP |
1831 | |
1832 | /* A new thread created by pthread_create inherits the signal mask | |
1833 | * from the parent. To avoid any signal being received by the | |
1834 | * listener thread, we block all signals temporarily in the parent, | |
1835 | * while we create the listener thread. | |
1836 | */ | |
1837 | sigfillset(&sig_all_blocked); | |
1838 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_parent_mask); | |
1839 | if (ret) { | |
d94d802c | 1840 | ERR("pthread_sigmask: %s", strerror(ret)); |
ae6a58bf WP |
1841 | } |
1842 | ||
1879f67f MG |
1843 | ret = pthread_attr_init(&thread_attr); |
1844 | if (ret) { | |
1845 | ERR("pthread_attr_init: %s", strerror(ret)); | |
1846 | } | |
1847 | ret = pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED); | |
1848 | if (ret) { | |
1849 | ERR("pthread_attr_setdetachstate: %s", strerror(ret)); | |
1850 | } | |
1851 | ||
ef4a06d9 JR |
1852 | if (global_apps.allowed) { |
1853 | pthread_mutex_lock(&ust_exit_mutex); | |
1854 | ret = pthread_create(&global_apps.ust_listener, &thread_attr, | |
1855 | ust_listener_thread, &global_apps); | |
1856 | if (ret) { | |
1857 | ERR("pthread_create global: %s", strerror(ret)); | |
1858 | } | |
1859 | global_apps.thread_active = 1; | |
1860 | pthread_mutex_unlock(&ust_exit_mutex); | |
1861 | } else { | |
1862 | handle_register_done(&global_apps); | |
d94d802c | 1863 | } |
e33f3265 | 1864 | |
8d20bf54 | 1865 | if (local_apps.allowed) { |
c0bbbd5a | 1866 | pthread_mutex_lock(&ust_exit_mutex); |
1879f67f | 1867 | ret = pthread_create(&local_apps.ust_listener, &thread_attr, |
dde70ea0 | 1868 | ust_listener_thread, &local_apps); |
d94d802c MD |
1869 | if (ret) { |
1870 | ERR("pthread_create local: %s", strerror(ret)); | |
1871 | } | |
e33f3265 | 1872 | local_apps.thread_active = 1; |
c0bbbd5a | 1873 | pthread_mutex_unlock(&ust_exit_mutex); |
8d20bf54 MD |
1874 | } else { |
1875 | handle_register_done(&local_apps); | |
1876 | } | |
1879f67f MG |
1877 | ret = pthread_attr_destroy(&thread_attr); |
1878 | if (ret) { | |
1879 | ERR("pthread_attr_destroy: %s", strerror(ret)); | |
1880 | } | |
8d20bf54 | 1881 | |
ae6a58bf WP |
1882 | /* Restore original signal mask in parent */ |
1883 | ret = pthread_sigmask(SIG_SETMASK, &orig_parent_mask, NULL); | |
1884 | if (ret) { | |
d94d802c | 1885 | ERR("pthread_sigmask: %s", strerror(ret)); |
ae6a58bf WP |
1886 | } |
1887 | ||
cf12a773 MD |
1888 | switch (timeout_mode) { |
1889 | case 1: /* timeout wait */ | |
95259bd0 MD |
1890 | do { |
1891 | ret = sem_timedwait(&constructor_wait, | |
1892 | &constructor_timeout); | |
1893 | } while (ret < 0 && errno == EINTR); | |
8aadb54a MD |
1894 | if (ret < 0) { |
1895 | switch (errno) { | |
1896 | case ETIMEDOUT: | |
1897 | ERR("Timed out waiting for lttng-sessiond"); | |
1898 | break; | |
1899 | case EINVAL: | |
1900 | PERROR("sem_timedwait"); | |
1901 | break; | |
1902 | default: | |
1903 | ERR("Unexpected error \"%s\" returned by sem_timedwait", | |
1904 | strerror(errno)); | |
1905 | } | |
cf12a773 MD |
1906 | } |
1907 | break; | |
7b766b16 | 1908 | case -1:/* wait forever */ |
95259bd0 MD |
1909 | do { |
1910 | ret = sem_wait(&constructor_wait); | |
1911 | } while (ret < 0 && errno == EINTR); | |
8aadb54a MD |
1912 | if (ret < 0) { |
1913 | switch (errno) { | |
1914 | case EINVAL: | |
1915 | PERROR("sem_wait"); | |
1916 | break; | |
1917 | default: | |
1918 | ERR("Unexpected error \"%s\" returned by sem_wait", | |
1919 | strerror(errno)); | |
1920 | } | |
1921 | } | |
cf12a773 | 1922 | break; |
7b766b16 | 1923 | case 0: /* no timeout */ |
cf12a773 | 1924 | break; |
11ff9c7d | 1925 | } |
2691221a MD |
1926 | } |
1927 | ||
17dfb34b MD |
1928 | static |
1929 | void lttng_ust_cleanup(int exiting) | |
1930 | { | |
efe0de09 | 1931 | cleanup_sock_info(&global_apps, exiting); |
932cfadb | 1932 | cleanup_sock_info(&local_apps, exiting); |
74f98bc9 | 1933 | local_apps.allowed = 0; |
ef4a06d9 | 1934 | global_apps.allowed = 0; |
efe0de09 MD |
1935 | /* |
1936 | * The teardown in this function all affect data structures | |
1937 | * accessed under the UST lock by the listener thread. This | |
1938 | * lock, along with the lttng_ust_comm_should_quit flag, ensure | |
1939 | * that none of these threads are accessing this data at this | |
1940 | * point. | |
1941 | */ | |
17dfb34b | 1942 | lttng_ust_abi_exit(); |
003fedf4 | 1943 | lttng_ust_events_exit(); |
d58d1454 | 1944 | lttng_perf_counter_exit(); |
34a91bdb | 1945 | lttng_ring_buffer_client_discard_rt_exit(); |
7dd08bec | 1946 | lttng_ring_buffer_client_discard_exit(); |
34a91bdb | 1947 | lttng_ring_buffer_client_overwrite_rt_exit(); |
7dd08bec MD |
1948 | lttng_ring_buffer_client_overwrite_exit(); |
1949 | lttng_ring_buffer_metadata_client_exit(); | |
cf73e0fe | 1950 | lttng_ust_statedump_destroy(); |
17dfb34b MD |
1951 | exit_tracepoint(); |
1952 | if (!exiting) { | |
1953 | /* Reinitialize values for fork */ | |
a4416702 | 1954 | sem_count = sem_count_initial_value; |
17dfb34b MD |
1955 | lttng_ust_comm_should_quit = 0; |
1956 | initialized = 0; | |
1957 | } | |
1958 | } | |
1959 | ||
edaa1431 | 1960 | void __attribute__((destructor)) lttng_ust_exit(void) |
2691221a MD |
1961 | { |
1962 | int ret; | |
1963 | ||
9eb62b9c MD |
1964 | /* |
1965 | * Using pthread_cancel here because: | |
1966 | * A) we don't want to hang application teardown. | |
1967 | * B) the thread is not allocating any resource. | |
1968 | */ | |
1ea11eab MD |
1969 | |
1970 | /* | |
1971 | * Require the communication thread to quit. Synchronize with | |
1972 | * mutexes to ensure it is not in a mutex critical section when | |
1973 | * pthread_cancel is later called. | |
1974 | */ | |
3327ac33 | 1975 | ust_lock_nocheck(); |
1ea11eab | 1976 | lttng_ust_comm_should_quit = 1; |
3327ac33 | 1977 | ust_unlock(); |
1ea11eab | 1978 | |
3327ac33 | 1979 | pthread_mutex_lock(&ust_exit_mutex); |
f5f94532 | 1980 | /* cancel threads */ |
e33f3265 MD |
1981 | if (global_apps.thread_active) { |
1982 | ret = pthread_cancel(global_apps.ust_listener); | |
1983 | if (ret) { | |
1984 | ERR("Error cancelling global ust listener thread: %s", | |
1985 | strerror(ret)); | |
1986 | } else { | |
1987 | global_apps.thread_active = 0; | |
1988 | } | |
2691221a | 1989 | } |
e33f3265 | 1990 | if (local_apps.thread_active) { |
8d20bf54 MD |
1991 | ret = pthread_cancel(local_apps.ust_listener); |
1992 | if (ret) { | |
d94d802c MD |
1993 | ERR("Error cancelling local ust listener thread: %s", |
1994 | strerror(ret)); | |
e33f3265 MD |
1995 | } else { |
1996 | local_apps.thread_active = 0; | |
8d20bf54 | 1997 | } |
8d20bf54 | 1998 | } |
3327ac33 | 1999 | pthread_mutex_unlock(&ust_exit_mutex); |
e33f3265 | 2000 | |
efe0de09 MD |
2001 | /* |
2002 | * Do NOT join threads: use of sys_futex makes it impossible to | |
2003 | * join the threads without using async-cancel, but async-cancel | |
2004 | * is delivered by a signal, which could hit the target thread | |
2005 | * anywhere in its code path, including while the ust_lock() is | |
2006 | * held, causing a deadlock for the other thread. Let the OS | |
2007 | * cleanup the threads if there are stalled in a syscall. | |
2008 | */ | |
17dfb34b | 2009 | lttng_ust_cleanup(1); |
2691221a | 2010 | } |
e822f505 MD |
2011 | |
2012 | /* | |
2013 | * We exclude the worker threads across fork and clone (except | |
2014 | * CLONE_VM), because these system calls only keep the forking thread | |
2015 | * running in the child. Therefore, we don't want to call fork or clone | |
2016 | * in the middle of an tracepoint or ust tracing state modification. | |
2017 | * Holding this mutex protects these structures across fork and clone. | |
2018 | */ | |
b728d87e | 2019 | void ust_before_fork(sigset_t *save_sigset) |
e822f505 MD |
2020 | { |
2021 | /* | |
2022 | * Disable signals. This is to avoid that the child intervenes | |
2023 | * before it is properly setup for tracing. It is safer to | |
2024 | * disable all signals, because then we know we are not breaking | |
2025 | * anything by restoring the original mask. | |
2026 | */ | |
2027 | sigset_t all_sigs; | |
2028 | int ret; | |
2029 | ||
c362addf MD |
2030 | /* Fixup lttng-ust TLS. */ |
2031 | lttng_ust_fixup_tls(); | |
2032 | ||
8c90a710 | 2033 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 2034 | return; |
e822f505 MD |
2035 | /* Disable signals */ |
2036 | sigfillset(&all_sigs); | |
b728d87e | 2037 | ret = sigprocmask(SIG_BLOCK, &all_sigs, save_sigset); |
e822f505 MD |
2038 | if (ret == -1) { |
2039 | PERROR("sigprocmask"); | |
2040 | } | |
458d678c PW |
2041 | |
2042 | pthread_mutex_lock(&ust_fork_mutex); | |
2043 | ||
3327ac33 | 2044 | ust_lock_nocheck(); |
e822f505 | 2045 | rcu_bp_before_fork(); |
791bf273 | 2046 | lttng_ust_lock_fd_tracker(); |
b6c0b199 | 2047 | lttng_perf_lock(); |
e822f505 MD |
2048 | } |
2049 | ||
b728d87e | 2050 | static void ust_after_fork_common(sigset_t *restore_sigset) |
e822f505 MD |
2051 | { |
2052 | int ret; | |
2053 | ||
17dfb34b | 2054 | DBG("process %d", getpid()); |
b6c0b199 | 2055 | lttng_perf_unlock(); |
791bf273 | 2056 | lttng_ust_unlock_fd_tracker(); |
17dfb34b | 2057 | ust_unlock(); |
458d678c PW |
2058 | |
2059 | pthread_mutex_unlock(&ust_fork_mutex); | |
2060 | ||
e822f505 | 2061 | /* Restore signals */ |
23c8854a | 2062 | ret = sigprocmask(SIG_SETMASK, restore_sigset, NULL); |
e822f505 MD |
2063 | if (ret == -1) { |
2064 | PERROR("sigprocmask"); | |
2065 | } | |
2066 | } | |
2067 | ||
b728d87e | 2068 | void ust_after_fork_parent(sigset_t *restore_sigset) |
e822f505 | 2069 | { |
8c90a710 | 2070 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 2071 | return; |
17dfb34b | 2072 | DBG("process %d", getpid()); |
e822f505 MD |
2073 | rcu_bp_after_fork_parent(); |
2074 | /* Release mutexes and reenable signals */ | |
b728d87e | 2075 | ust_after_fork_common(restore_sigset); |
e822f505 MD |
2076 | } |
2077 | ||
17dfb34b MD |
2078 | /* |
2079 | * After fork, in the child, we need to cleanup all the leftover state, | |
2080 | * except the worker thread which already magically disappeared thanks | |
2081 | * to the weird Linux fork semantics. After tyding up, we call | |
2082 | * lttng_ust_init() again to start over as a new PID. | |
2083 | * | |
2084 | * This is meant for forks() that have tracing in the child between the | |
2085 | * fork and following exec call (if there is any). | |
2086 | */ | |
b728d87e | 2087 | void ust_after_fork_child(sigset_t *restore_sigset) |
e822f505 | 2088 | { |
8c90a710 | 2089 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 2090 | return; |
f575e049 | 2091 | lttng_context_vpid_reset(); |
8478887d | 2092 | lttng_context_vtid_reset(); |
5fe0ab0b | 2093 | lttng_context_procname_reset(); |
17dfb34b | 2094 | DBG("process %d", getpid()); |
e822f505 MD |
2095 | /* Release urcu mutexes */ |
2096 | rcu_bp_after_fork_child(); | |
17dfb34b | 2097 | lttng_ust_cleanup(0); |
e822f505 | 2098 | /* Release mutexes and reenable signals */ |
b728d87e | 2099 | ust_after_fork_common(restore_sigset); |
318dfea9 | 2100 | lttng_ust_init(); |
e822f505 | 2101 | } |
95c25348 | 2102 | |
246be17e | 2103 | void lttng_ust_sockinfo_session_enabled(void *owner) |
95c25348 PW |
2104 | { |
2105 | struct sock_info *sock_info = owner; | |
37dddb65 | 2106 | sock_info->statedump_pending = 1; |
95c25348 | 2107 | } |