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> | |
b2292d85 | 30 | #include <dlfcn.h> |
7fc90dca | 31 | #include <fcntl.h> |
2691221a MD |
32 | #include <unistd.h> |
33 | #include <errno.h> | |
d9e99d10 | 34 | #include <pthread.h> |
11ff9c7d MD |
35 | #include <semaphore.h> |
36 | #include <time.h> | |
1ea11eab | 37 | #include <assert.h> |
e822f505 | 38 | #include <signal.h> |
6f97f9c2 | 39 | #include <limits.h> |
95259bd0 | 40 | #include <urcu/uatomic.h> |
80e2814b | 41 | #include <urcu/futex.h> |
c117fb1b | 42 | #include <urcu/compiler.h> |
1ea11eab | 43 | |
4318ae1b | 44 | #include <lttng/ust-events.h> |
4318ae1b | 45 | #include <lttng/ust-abi.h> |
4318ae1b | 46 | #include <lttng/ust.h> |
7bc53e94 | 47 | #include <lttng/ust-error.h> |
74d81a6c | 48 | #include <lttng/ust-ctl.h> |
8c90a710 | 49 | #include <urcu/tls-compat.h> |
44c72f10 | 50 | #include <ust-comm.h> |
6548fca4 | 51 | #include <ust-fd.h> |
44c72f10 | 52 | #include <usterr-signal-safe.h> |
cd54f6d9 | 53 | #include <helper.h> |
44c72f10 | 54 | #include "tracepoint-internal.h" |
7dd08bec | 55 | #include "lttng-tracer-core.h" |
08114193 | 56 | #include "compat.h" |
6f97f9c2 | 57 | #include "../libringbuffer/rb-init.h" |
cf73e0fe | 58 | #include "lttng-ust-statedump.h" |
f9364363 | 59 | #include "clock.h" |
5e1b7b8b | 60 | #include "../libringbuffer/getcpu.h" |
13efba44 | 61 | #include "getenv.h" |
edaa1431 | 62 | |
b2292d85 FD |
63 | /* Concatenate lttng ust shared library name with its major version number. */ |
64 | #define LTTNG_UST_LIB_SO_NAME "liblttng-ust.so." LTTNG_UST_LIBRARY_VERSION_MAJOR | |
65 | ||
edaa1431 MD |
66 | /* |
67 | * Has lttng ust comm constructor been called ? | |
68 | */ | |
69 | static int initialized; | |
70 | ||
1ea11eab | 71 | /* |
17dfb34b MD |
72 | * The ust_lock/ust_unlock lock is used as a communication thread mutex. |
73 | * Held when handling a command, also held by fork() to deal with | |
74 | * removal of threads, and by exit path. | |
3327ac33 MD |
75 | * |
76 | * The UST lock is the centralized mutex across UST tracing control and | |
77 | * probe registration. | |
78 | * | |
79 | * ust_exit_mutex must never nest in ust_mutex. | |
d58d1454 | 80 | * |
4770bd47 MD |
81 | * ust_fork_mutex must never nest in ust_mutex. |
82 | * | |
d58d1454 MD |
83 | * ust_mutex_nest is a per-thread nesting counter, allowing the perf |
84 | * counter lazy initialization called by events within the statedump, | |
85 | * which traces while the ust_mutex is held. | |
4770bd47 MD |
86 | * |
87 | * ust_lock nests within the dynamic loader lock (within glibc) because | |
88 | * it is taken within the library constructor. | |
3327ac33 MD |
89 | */ |
90 | static pthread_mutex_t ust_mutex = PTHREAD_MUTEX_INITIALIZER; | |
91 | ||
d58d1454 | 92 | /* Allow nesting the ust_mutex within the same thread. */ |
16adecf1 | 93 | static DEFINE_URCU_TLS(int, ust_mutex_nest); |
d58d1454 | 94 | |
3327ac33 MD |
95 | /* |
96 | * ust_exit_mutex protects thread_active variable wrt thread exit. It | |
97 | * cannot be done by ust_mutex because pthread_cancel(), which takes an | |
98 | * internal libc lock, cannot nest within ust_mutex. | |
99 | * | |
100 | * It never nests within a ust_mutex. | |
1ea11eab | 101 | */ |
3327ac33 | 102 | static pthread_mutex_t ust_exit_mutex = PTHREAD_MUTEX_INITIALIZER; |
1ea11eab | 103 | |
458d678c PW |
104 | /* |
105 | * ust_fork_mutex protects base address statedump tracing against forks. It | |
106 | * prevents the dynamic loader lock to be taken (by base address statedump | |
107 | * tracing) while a fork is happening, thus preventing deadlock issues with | |
108 | * the dynamic loader lock. | |
109 | */ | |
110 | static pthread_mutex_t ust_fork_mutex = PTHREAD_MUTEX_INITIALIZER; | |
111 | ||
1ea11eab MD |
112 | /* Should the ust comm thread quit ? */ |
113 | static int lttng_ust_comm_should_quit; | |
114 | ||
07b57e5e MD |
115 | /* |
116 | * This variable can be tested by applications to check whether | |
117 | * lttng-ust is loaded. They simply have to define their own | |
118 | * "lttng_ust_loaded" weak symbol, and test it. It is set to 1 by the | |
119 | * library constructor. | |
120 | */ | |
121 | int lttng_ust_loaded __attribute__((weak)); | |
122 | ||
3327ac33 | 123 | /* |
d58d1454 | 124 | * Return 0 on success, -1 if should quit. |
3327ac33 | 125 | * The lock is taken in both cases. |
d58d1454 | 126 | * Signal-safe. |
3327ac33 MD |
127 | */ |
128 | int ust_lock(void) | |
129 | { | |
d58d1454 | 130 | sigset_t sig_all_blocked, orig_mask; |
e446ad80 | 131 | int ret, oldstate; |
d58d1454 | 132 | |
e446ad80 MD |
133 | ret = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldstate); |
134 | if (ret) { | |
135 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
136 | } | |
137 | if (oldstate != PTHREAD_CANCEL_ENABLE) { | |
138 | ERR("pthread_setcancelstate: unexpected oldstate"); | |
139 | } | |
d58d1454 MD |
140 | sigfillset(&sig_all_blocked); |
141 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
142 | if (ret) { | |
143 | ERR("pthread_sigmask: %s", strerror(ret)); | |
144 | } | |
145 | if (!URCU_TLS(ust_mutex_nest)++) | |
146 | pthread_mutex_lock(&ust_mutex); | |
147 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
148 | if (ret) { | |
149 | ERR("pthread_sigmask: %s", strerror(ret)); | |
150 | } | |
3327ac33 MD |
151 | if (lttng_ust_comm_should_quit) { |
152 | return -1; | |
153 | } else { | |
154 | return 0; | |
155 | } | |
156 | } | |
157 | ||
158 | /* | |
159 | * ust_lock_nocheck() can be used in constructors/destructors, because | |
160 | * they are already nested within the dynamic loader lock, and therefore | |
161 | * have exclusive access against execution of liblttng-ust destructor. | |
d58d1454 | 162 | * Signal-safe. |
3327ac33 MD |
163 | */ |
164 | void ust_lock_nocheck(void) | |
165 | { | |
d58d1454 | 166 | sigset_t sig_all_blocked, orig_mask; |
e446ad80 | 167 | int ret, oldstate; |
d58d1454 | 168 | |
e446ad80 MD |
169 | ret = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldstate); |
170 | if (ret) { | |
171 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
172 | } | |
173 | if (oldstate != PTHREAD_CANCEL_ENABLE) { | |
174 | ERR("pthread_setcancelstate: unexpected oldstate"); | |
175 | } | |
d58d1454 MD |
176 | sigfillset(&sig_all_blocked); |
177 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
178 | if (ret) { | |
179 | ERR("pthread_sigmask: %s", strerror(ret)); | |
180 | } | |
181 | if (!URCU_TLS(ust_mutex_nest)++) | |
182 | pthread_mutex_lock(&ust_mutex); | |
183 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
184 | if (ret) { | |
185 | ERR("pthread_sigmask: %s", strerror(ret)); | |
186 | } | |
3327ac33 MD |
187 | } |
188 | ||
d58d1454 MD |
189 | /* |
190 | * Signal-safe. | |
191 | */ | |
3327ac33 MD |
192 | void ust_unlock(void) |
193 | { | |
d58d1454 | 194 | sigset_t sig_all_blocked, orig_mask; |
e446ad80 | 195 | int ret, oldstate; |
d58d1454 MD |
196 | |
197 | sigfillset(&sig_all_blocked); | |
198 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
199 | if (ret) { | |
200 | ERR("pthread_sigmask: %s", strerror(ret)); | |
201 | } | |
202 | if (!--URCU_TLS(ust_mutex_nest)) | |
203 | pthread_mutex_unlock(&ust_mutex); | |
204 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
205 | if (ret) { | |
206 | ERR("pthread_sigmask: %s", strerror(ret)); | |
207 | } | |
e446ad80 MD |
208 | ret = pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldstate); |
209 | if (ret) { | |
210 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
211 | } | |
212 | if (oldstate != PTHREAD_CANCEL_DISABLE) { | |
213 | ERR("pthread_setcancelstate: unexpected oldstate"); | |
214 | } | |
3327ac33 MD |
215 | } |
216 | ||
11ff9c7d MD |
217 | /* |
218 | * Wait for either of these before continuing to the main | |
219 | * program: | |
220 | * - the register_done message from sessiond daemon | |
221 | * (will let the sessiond daemon enable sessions before main | |
222 | * starts.) | |
223 | * - sessiond daemon is not reachable. | |
224 | * - timeout (ensuring applications are resilient to session | |
225 | * daemon problems). | |
226 | */ | |
227 | static sem_t constructor_wait; | |
950aab0c MD |
228 | /* |
229 | * Doing this for both the global and local sessiond. | |
230 | */ | |
e85887ff GAPG |
231 | enum { |
232 | sem_count_initial_value = 4, | |
233 | }; | |
234 | ||
235 | static int sem_count = sem_count_initial_value; | |
11ff9c7d | 236 | |
e8508a49 MD |
237 | /* |
238 | * Counting nesting within lttng-ust. Used to ensure that calling fork() | |
239 | * from liblttng-ust does not execute the pre/post fork handlers. | |
240 | */ | |
8c90a710 | 241 | static DEFINE_URCU_TLS(int, lttng_ust_nest_count); |
e8508a49 | 242 | |
1ea11eab MD |
243 | /* |
244 | * Info about socket and associated listener thread. | |
245 | */ | |
246 | struct sock_info { | |
11ff9c7d | 247 | const char *name; |
1ea11eab | 248 | pthread_t ust_listener; /* listener thread */ |
46050b1a | 249 | int root_handle; |
e85887ff | 250 | int registration_done; |
8d20bf54 | 251 | int allowed; |
44e073f5 | 252 | int global; |
e33f3265 | 253 | int thread_active; |
7fc90dca MD |
254 | |
255 | char sock_path[PATH_MAX]; | |
256 | int socket; | |
32ce8569 | 257 | int notify_socket; |
7fc90dca MD |
258 | |
259 | char wait_shm_path[PATH_MAX]; | |
260 | char *wait_shm_mmap; | |
37dddb65 MD |
261 | /* Keep track of lazy state dump not performed yet. */ |
262 | int statedump_pending; | |
e85887ff | 263 | int initial_statedump_done; |
1ea11eab | 264 | }; |
2691221a MD |
265 | |
266 | /* Socket from app (connect) to session daemon (listen) for communication */ | |
1ea11eab | 267 | struct sock_info global_apps = { |
11ff9c7d | 268 | .name = "global", |
44e073f5 | 269 | .global = 1, |
7fc90dca | 270 | |
46050b1a | 271 | .root_handle = -1, |
e85887ff | 272 | .registration_done = 0, |
9d2dfb47 | 273 | .allowed = 0, |
e33f3265 | 274 | .thread_active = 0, |
7fc90dca | 275 | |
32ce8569 | 276 | .sock_path = LTTNG_DEFAULT_RUNDIR "/" LTTNG_UST_SOCK_FILENAME, |
7fc90dca | 277 | .socket = -1, |
32ce8569 | 278 | .notify_socket = -1, |
7fc90dca | 279 | |
32ce8569 | 280 | .wait_shm_path = "/" LTTNG_UST_WAIT_FILENAME, |
95c25348 | 281 | |
37dddb65 | 282 | .statedump_pending = 0, |
e85887ff | 283 | .initial_statedump_done = 0, |
1ea11eab | 284 | }; |
2691221a MD |
285 | |
286 | /* TODO: allow global_apps_sock_path override */ | |
287 | ||
1ea11eab | 288 | struct sock_info local_apps = { |
11ff9c7d | 289 | .name = "local", |
44e073f5 | 290 | .global = 0, |
46050b1a | 291 | .root_handle = -1, |
e85887ff | 292 | .registration_done = 0, |
8d20bf54 | 293 | .allowed = 0, /* Check setuid bit first */ |
e33f3265 | 294 | .thread_active = 0, |
7fc90dca MD |
295 | |
296 | .socket = -1, | |
32ce8569 | 297 | .notify_socket = -1, |
95c25348 | 298 | |
37dddb65 | 299 | .statedump_pending = 0, |
e85887ff | 300 | .initial_statedump_done = 0, |
1ea11eab | 301 | }; |
2691221a | 302 | |
37ed587a MD |
303 | static int wait_poll_fallback; |
304 | ||
74d81a6c MD |
305 | static const char *cmd_name_mapping[] = { |
306 | [ LTTNG_UST_RELEASE ] = "Release", | |
307 | [ LTTNG_UST_SESSION ] = "Create Session", | |
308 | [ LTTNG_UST_TRACER_VERSION ] = "Get Tracer Version", | |
309 | ||
310 | [ LTTNG_UST_TRACEPOINT_LIST ] = "Create Tracepoint List", | |
311 | [ LTTNG_UST_WAIT_QUIESCENT ] = "Wait for Quiescent State", | |
312 | [ LTTNG_UST_REGISTER_DONE ] = "Registration Done", | |
313 | [ LTTNG_UST_TRACEPOINT_FIELD_LIST ] = "Create Tracepoint Field List", | |
314 | ||
315 | /* Session FD commands */ | |
316 | [ LTTNG_UST_CHANNEL ] = "Create Channel", | |
317 | [ LTTNG_UST_SESSION_START ] = "Start Session", | |
318 | [ LTTNG_UST_SESSION_STOP ] = "Stop Session", | |
319 | ||
320 | /* Channel FD commands */ | |
321 | [ LTTNG_UST_STREAM ] = "Create Stream", | |
322 | [ LTTNG_UST_EVENT ] = "Create Event", | |
323 | ||
324 | /* Event and Channel FD commands */ | |
325 | [ LTTNG_UST_CONTEXT ] = "Create Context", | |
326 | [ LTTNG_UST_FLUSH_BUFFER ] = "Flush Buffer", | |
327 | ||
328 | /* Event, Channel and Session commands */ | |
329 | [ LTTNG_UST_ENABLE ] = "Enable", | |
330 | [ LTTNG_UST_DISABLE ] = "Disable", | |
331 | ||
332 | /* Tracepoint list commands */ | |
333 | [ LTTNG_UST_TRACEPOINT_LIST_GET ] = "List Next Tracepoint", | |
334 | [ LTTNG_UST_TRACEPOINT_FIELD_LIST_GET ] = "List Next Tracepoint Field", | |
335 | ||
336 | /* Event FD commands */ | |
337 | [ LTTNG_UST_FILTER ] = "Create Filter", | |
75582b3a | 338 | [ LTTNG_UST_EXCLUSION ] = "Add exclusions to event", |
74d81a6c MD |
339 | }; |
340 | ||
ff517991 MD |
341 | static const char *str_timeout; |
342 | static int got_timeout_env; | |
343 | ||
7dd08bec | 344 | extern void lttng_ring_buffer_client_overwrite_init(void); |
34a91bdb | 345 | extern void lttng_ring_buffer_client_overwrite_rt_init(void); |
7dd08bec | 346 | extern void lttng_ring_buffer_client_discard_init(void); |
34a91bdb | 347 | extern void lttng_ring_buffer_client_discard_rt_init(void); |
7dd08bec MD |
348 | extern void lttng_ring_buffer_metadata_client_init(void); |
349 | extern void lttng_ring_buffer_client_overwrite_exit(void); | |
34a91bdb | 350 | extern void lttng_ring_buffer_client_overwrite_rt_exit(void); |
7dd08bec | 351 | extern void lttng_ring_buffer_client_discard_exit(void); |
34a91bdb | 352 | extern void lttng_ring_buffer_client_discard_rt_exit(void); |
7dd08bec | 353 | extern void lttng_ring_buffer_metadata_client_exit(void); |
edaa1431 | 354 | |
9d2dfb47 JR |
355 | static char *get_map_shm(struct sock_info *sock_info); |
356 | ||
405be658 MD |
357 | ssize_t lttng_ust_read(int fd, void *buf, size_t len) |
358 | { | |
359 | ssize_t ret; | |
360 | size_t copied = 0, to_copy = len; | |
361 | ||
362 | do { | |
363 | ret = read(fd, buf + copied, to_copy); | |
364 | if (ret > 0) { | |
365 | copied += ret; | |
366 | to_copy -= ret; | |
367 | } | |
368 | } while ((ret > 0 && to_copy > 0) | |
369 | || (ret < 0 && errno == EINTR)); | |
370 | if (ret > 0) { | |
371 | ret = copied; | |
372 | } | |
373 | return ret; | |
374 | } | |
3c6f6263 AM |
375 | /* |
376 | * Returns the HOME directory path. Caller MUST NOT free(3) the returned | |
377 | * pointer. | |
378 | */ | |
379 | static | |
380 | const char *get_lttng_home_dir(void) | |
381 | { | |
382 | const char *val; | |
383 | ||
6f626d28 | 384 | val = (const char *) lttng_getenv("LTTNG_HOME"); |
3c6f6263 AM |
385 | if (val != NULL) { |
386 | return val; | |
387 | } | |
6f626d28 | 388 | return (const char *) lttng_getenv("HOME"); |
3c6f6263 AM |
389 | } |
390 | ||
a903623f MD |
391 | /* |
392 | * Force a read (imply TLS fixup for dlopen) of TLS variables. | |
393 | */ | |
394 | static | |
395 | void lttng_fixup_nest_count_tls(void) | |
396 | { | |
8c90a710 | 397 | asm volatile ("" : : "m" (URCU_TLS(lttng_ust_nest_count))); |
a903623f MD |
398 | } |
399 | ||
d58d1454 MD |
400 | static |
401 | void lttng_fixup_ust_mutex_nest_tls(void) | |
402 | { | |
403 | asm volatile ("" : : "m" (URCU_TLS(ust_mutex_nest))); | |
404 | } | |
405 | ||
1556a549 MD |
406 | /* |
407 | * Fixup urcu bp TLS. | |
408 | */ | |
409 | static | |
410 | void lttng_fixup_urcu_bp_tls(void) | |
411 | { | |
412 | rcu_read_lock(); | |
413 | rcu_read_unlock(); | |
414 | } | |
415 | ||
c362addf MD |
416 | void lttng_ust_fixup_tls(void) |
417 | { | |
418 | lttng_fixup_urcu_bp_tls(); | |
419 | lttng_fixup_ringbuffer_tls(); | |
420 | lttng_fixup_vtid_tls(); | |
421 | lttng_fixup_nest_count_tls(); | |
422 | lttng_fixup_procname_tls(); | |
423 | lttng_fixup_ust_mutex_nest_tls(); | |
6548fca4 | 424 | lttng_ust_fixup_fd_tracker_tls(); |
c362addf MD |
425 | } |
426 | ||
32ce8569 MD |
427 | int lttng_get_notify_socket(void *owner) |
428 | { | |
429 | struct sock_info *info = owner; | |
430 | ||
431 | return info->notify_socket; | |
432 | } | |
433 | ||
74d81a6c MD |
434 | static |
435 | void print_cmd(int cmd, int handle) | |
436 | { | |
437 | const char *cmd_name = "Unknown"; | |
438 | ||
fd67a004 MD |
439 | if (cmd >= 0 && cmd < LTTNG_ARRAY_SIZE(cmd_name_mapping) |
440 | && cmd_name_mapping[cmd]) { | |
74d81a6c MD |
441 | cmd_name = cmd_name_mapping[cmd]; |
442 | } | |
fd67a004 MD |
443 | DBG("Message Received \"%s\" (%d), Handle \"%s\" (%d)", |
444 | cmd_name, cmd, | |
74d81a6c MD |
445 | lttng_ust_obj_get_name(handle), handle); |
446 | } | |
447 | ||
9d2dfb47 JR |
448 | static |
449 | int setup_global_apps(void) | |
450 | { | |
451 | int ret = 0; | |
452 | assert(!global_apps.wait_shm_mmap); | |
453 | ||
454 | global_apps.wait_shm_mmap = get_map_shm(&global_apps); | |
455 | if (!global_apps.wait_shm_mmap) { | |
456 | WARN("Unable to get map shm for global apps. Disabling LTTng-UST global tracing."); | |
457 | global_apps.allowed = 0; | |
458 | ret = -EIO; | |
459 | goto error; | |
460 | } | |
461 | ||
462 | global_apps.allowed = 1; | |
463 | error: | |
464 | return ret; | |
465 | } | |
2691221a | 466 | static |
8d20bf54 | 467 | int setup_local_apps(void) |
2691221a | 468 | { |
9d2dfb47 | 469 | int ret = 0; |
2691221a | 470 | const char *home_dir; |
7fc90dca | 471 | uid_t uid; |
2691221a | 472 | |
9d2dfb47 JR |
473 | assert(!local_apps.wait_shm_mmap); |
474 | ||
7fc90dca | 475 | uid = getuid(); |
8d20bf54 MD |
476 | /* |
477 | * Disallow per-user tracing for setuid binaries. | |
478 | */ | |
7fc90dca | 479 | if (uid != geteuid()) { |
9ec6895c | 480 | assert(local_apps.allowed == 0); |
9d2dfb47 JR |
481 | ret = 0; |
482 | goto end; | |
8d20bf54 | 483 | } |
3c6f6263 | 484 | home_dir = get_lttng_home_dir(); |
9ec6895c MD |
485 | if (!home_dir) { |
486 | WARN("HOME environment variable not set. Disabling LTTng-UST per-user tracing."); | |
487 | assert(local_apps.allowed == 0); | |
9d2dfb47 JR |
488 | ret = -ENOENT; |
489 | goto end; | |
9ec6895c MD |
490 | } |
491 | local_apps.allowed = 1; | |
32ce8569 MD |
492 | snprintf(local_apps.sock_path, PATH_MAX, "%s/%s/%s", |
493 | home_dir, | |
494 | LTTNG_DEFAULT_HOME_RUNDIR, | |
495 | LTTNG_UST_SOCK_FILENAME); | |
496 | snprintf(local_apps.wait_shm_path, PATH_MAX, "/%s-%u", | |
497 | LTTNG_UST_WAIT_FILENAME, | |
498 | uid); | |
9d2dfb47 JR |
499 | |
500 | local_apps.wait_shm_mmap = get_map_shm(&local_apps); | |
501 | if (!local_apps.wait_shm_mmap) { | |
502 | WARN("Unable to get map shm for local apps. Disabling LTTng-UST per-user tracing."); | |
503 | local_apps.allowed = 0; | |
504 | ret = -EIO; | |
505 | goto end; | |
506 | } | |
507 | end: | |
508 | return ret; | |
2691221a MD |
509 | } |
510 | ||
ff517991 | 511 | /* |
451d66b2 | 512 | * Get socket timeout, in ms. |
28515902 | 513 | * -1: wait forever. 0: don't wait. >0: timeout, in ms. |
ff517991 MD |
514 | */ |
515 | static | |
516 | long get_timeout(void) | |
517 | { | |
518 | long constructor_delay_ms = LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS; | |
519 | ||
520 | if (!got_timeout_env) { | |
6f626d28 | 521 | str_timeout = lttng_getenv("LTTNG_UST_REGISTER_TIMEOUT"); |
ff517991 MD |
522 | got_timeout_env = 1; |
523 | } | |
524 | if (str_timeout) | |
525 | constructor_delay_ms = strtol(str_timeout, NULL, 10); | |
5cf81d53 MD |
526 | /* All negative values are considered as "-1". */ |
527 | if (constructor_delay_ms < -1) | |
528 | constructor_delay_ms = -1; | |
ff517991 MD |
529 | return constructor_delay_ms; |
530 | } | |
531 | ||
451d66b2 | 532 | /* Timeout for notify socket send and recv. */ |
ff517991 MD |
533 | static |
534 | long get_notify_sock_timeout(void) | |
535 | { | |
536 | return get_timeout(); | |
537 | } | |
538 | ||
451d66b2 MD |
539 | /* Timeout for connecting to cmd and notify sockets. */ |
540 | static | |
541 | long get_connect_sock_timeout(void) | |
542 | { | |
543 | return get_timeout(); | |
544 | } | |
545 | ||
ff517991 | 546 | /* |
28515902 | 547 | * Return values: -1: wait forever. 0: don't wait. 1: timeout wait. |
ff517991 MD |
548 | */ |
549 | static | |
550 | int get_constructor_timeout(struct timespec *constructor_timeout) | |
551 | { | |
552 | long constructor_delay_ms; | |
553 | int ret; | |
554 | ||
555 | constructor_delay_ms = get_timeout(); | |
556 | ||
557 | switch (constructor_delay_ms) { | |
558 | case -1:/* fall-through */ | |
559 | case 0: | |
560 | return constructor_delay_ms; | |
561 | default: | |
562 | break; | |
563 | } | |
564 | ||
565 | /* | |
566 | * If we are unable to find the current time, don't wait. | |
567 | */ | |
568 | ret = clock_gettime(CLOCK_REALTIME, constructor_timeout); | |
569 | if (ret) { | |
28515902 JG |
570 | /* Don't wait. */ |
571 | return 0; | |
ff517991 MD |
572 | } |
573 | constructor_timeout->tv_sec += constructor_delay_ms / 1000UL; | |
574 | constructor_timeout->tv_nsec += | |
575 | (constructor_delay_ms % 1000UL) * 1000000UL; | |
576 | if (constructor_timeout->tv_nsec >= 1000000000UL) { | |
577 | constructor_timeout->tv_sec++; | |
578 | constructor_timeout->tv_nsec -= 1000000000UL; | |
579 | } | |
28515902 | 580 | /* Timeout wait (constructor_delay_ms). */ |
ff517991 MD |
581 | return 1; |
582 | } | |
583 | ||
6f97f9c2 | 584 | static |
b2c5f61a | 585 | void get_allow_blocking(void) |
6f97f9c2 | 586 | { |
b2c5f61a MD |
587 | const char *str_allow_blocking = |
588 | lttng_getenv("LTTNG_UST_ALLOW_BLOCKING"); | |
589 | ||
590 | if (str_allow_blocking) { | |
591 | DBG("%s environment variable is set", | |
592 | "LTTNG_UST_ALLOW_BLOCKING"); | |
593 | lttng_ust_ringbuffer_set_allow_blocking(); | |
6f97f9c2 MD |
594 | } |
595 | } | |
596 | ||
2691221a | 597 | static |
32ce8569 | 598 | int register_to_sessiond(int socket, enum ustctl_socket_type type) |
2691221a | 599 | { |
32ce8569 MD |
600 | return ustcomm_send_reg_msg(socket, |
601 | type, | |
602 | CAA_BITS_PER_LONG, | |
603 | lttng_alignof(uint8_t) * CHAR_BIT, | |
604 | lttng_alignof(uint16_t) * CHAR_BIT, | |
605 | lttng_alignof(uint32_t) * CHAR_BIT, | |
606 | lttng_alignof(uint64_t) * CHAR_BIT, | |
607 | lttng_alignof(unsigned long) * CHAR_BIT); | |
2691221a MD |
608 | } |
609 | ||
d9e99d10 | 610 | static |
57773204 | 611 | int send_reply(int sock, struct ustcomm_ust_reply *lur) |
d9e99d10 | 612 | { |
9eb62b9c | 613 | ssize_t len; |
d3a492d1 | 614 | |
57773204 | 615 | len = ustcomm_send_unix_sock(sock, lur, sizeof(*lur)); |
d3a492d1 | 616 | switch (len) { |
a4be8962 | 617 | case sizeof(*lur): |
d3a492d1 MD |
618 | DBG("message successfully sent"); |
619 | return 0; | |
7bc53e94 MD |
620 | default: |
621 | if (len == -ECONNRESET) { | |
622 | DBG("remote end closed connection"); | |
d3a492d1 MD |
623 | return 0; |
624 | } | |
7bc53e94 MD |
625 | if (len < 0) |
626 | return len; | |
627 | DBG("incorrect message size: %zd", len); | |
628 | return -EINVAL; | |
d3a492d1 MD |
629 | } |
630 | } | |
631 | ||
632 | static | |
e85887ff | 633 | void decrement_sem_count(unsigned int count) |
11ff9c7d MD |
634 | { |
635 | int ret; | |
636 | ||
e85887ff GAPG |
637 | assert(uatomic_read(&sem_count) >= count); |
638 | ||
56cd7e2f | 639 | if (uatomic_read(&sem_count) <= 0) { |
e85887ff | 640 | return; |
56cd7e2f | 641 | } |
e85887ff GAPG |
642 | |
643 | ret = uatomic_add_return(&sem_count, -count); | |
95259bd0 MD |
644 | if (ret == 0) { |
645 | ret = sem_post(&constructor_wait); | |
646 | assert(!ret); | |
647 | } | |
e85887ff GAPG |
648 | } |
649 | ||
650 | static | |
651 | int handle_register_done(struct sock_info *sock_info) | |
652 | { | |
653 | if (sock_info->registration_done) | |
654 | return 0; | |
655 | sock_info->registration_done = 1; | |
656 | ||
657 | decrement_sem_count(1); | |
658 | ||
659 | return 0; | |
660 | } | |
661 | ||
662 | static | |
663 | int handle_register_failed(struct sock_info *sock_info) | |
664 | { | |
665 | if (sock_info->registration_done) | |
666 | return 0; | |
667 | sock_info->registration_done = 1; | |
668 | sock_info->initial_statedump_done = 1; | |
669 | ||
670 | decrement_sem_count(2); | |
671 | ||
11ff9c7d MD |
672 | return 0; |
673 | } | |
674 | ||
37dddb65 MD |
675 | /* |
676 | * Only execute pending statedump after the constructor semaphore has | |
e85887ff GAPG |
677 | * been posted by the current listener thread. This means statedump will |
678 | * only be performed after the "registration done" command is received | |
679 | * from this thread's session daemon. | |
37dddb65 MD |
680 | * |
681 | * This ensures we don't run into deadlock issues with the dynamic | |
682 | * loader mutex, which is held while the constructor is called and | |
683 | * waiting on the constructor semaphore. All operations requiring this | |
684 | * dynamic loader lock need to be postponed using this mechanism. | |
e85887ff GAPG |
685 | * |
686 | * In a scenario with two session daemons connected to the application, | |
687 | * it is possible that the first listener thread which receives the | |
688 | * registration done command issues its statedump while the dynamic | |
689 | * loader lock is still held by the application constructor waiting on | |
690 | * the semaphore. It will however be allowed to proceed when the | |
691 | * second session daemon sends the registration done command to the | |
692 | * second listener thread. This situation therefore does not produce | |
693 | * a deadlock. | |
37dddb65 MD |
694 | */ |
695 | static | |
696 | void handle_pending_statedump(struct sock_info *sock_info) | |
697 | { | |
e85887ff | 698 | if (sock_info->registration_done && sock_info->statedump_pending) { |
37dddb65 | 699 | sock_info->statedump_pending = 0; |
2932a87f | 700 | pthread_mutex_lock(&ust_fork_mutex); |
37dddb65 | 701 | lttng_handle_pending_statedump(sock_info); |
458d678c | 702 | pthread_mutex_unlock(&ust_fork_mutex); |
e85887ff GAPG |
703 | |
704 | if (!sock_info->initial_statedump_done) { | |
705 | sock_info->initial_statedump_done = 1; | |
706 | decrement_sem_count(1); | |
707 | } | |
37dddb65 MD |
708 | } |
709 | } | |
710 | ||
11ff9c7d MD |
711 | static |
712 | int handle_message(struct sock_info *sock_info, | |
57773204 | 713 | int sock, struct ustcomm_ust_msg *lum) |
d3a492d1 | 714 | { |
1ea11eab | 715 | int ret = 0; |
b61ce3b2 | 716 | const struct lttng_ust_objd_ops *ops; |
57773204 | 717 | struct ustcomm_ust_reply lur; |
ef9ff354 | 718 | union ust_args args; |
8e696cfa | 719 | char ctxstr[LTTNG_UST_SYM_NAME_LEN]; /* App context string. */ |
40003310 | 720 | ssize_t len; |
1ea11eab | 721 | |
46050b1a MD |
722 | memset(&lur, 0, sizeof(lur)); |
723 | ||
3327ac33 | 724 | if (ust_lock()) { |
74d81a6c | 725 | ret = -LTTNG_UST_ERR_EXITING; |
0dafcd63 | 726 | goto error; |
1ea11eab | 727 | } |
9eb62b9c | 728 | |
46050b1a MD |
729 | ops = objd_ops(lum->handle); |
730 | if (!ops) { | |
731 | ret = -ENOENT; | |
0dafcd63 | 732 | goto error; |
1ea11eab | 733 | } |
46050b1a MD |
734 | |
735 | switch (lum->cmd) { | |
11ff9c7d MD |
736 | case LTTNG_UST_REGISTER_DONE: |
737 | if (lum->handle == LTTNG_UST_ROOT_HANDLE) | |
edaa1431 | 738 | ret = handle_register_done(sock_info); |
11ff9c7d MD |
739 | else |
740 | ret = -EINVAL; | |
741 | break; | |
46050b1a MD |
742 | case LTTNG_UST_RELEASE: |
743 | if (lum->handle == LTTNG_UST_ROOT_HANDLE) | |
744 | ret = -EPERM; | |
745 | else | |
1849ef7c | 746 | ret = lttng_ust_objd_unref(lum->handle, 1); |
d9e99d10 | 747 | break; |
2d78951a MD |
748 | case LTTNG_UST_FILTER: |
749 | { | |
750 | /* Receive filter data */ | |
f488575f | 751 | struct lttng_ust_filter_bytecode_node *bytecode; |
2d78951a | 752 | |
cd54f6d9 | 753 | if (lum->u.filter.data_size > FILTER_BYTECODE_MAX_LEN) { |
7bc53e94 | 754 | ERR("Filter data size is too large: %u bytes", |
2d78951a MD |
755 | lum->u.filter.data_size); |
756 | ret = -EINVAL; | |
757 | goto error; | |
758 | } | |
2734ca65 | 759 | |
885b1dfd | 760 | if (lum->u.filter.reloc_offset > lum->u.filter.data_size) { |
7bc53e94 | 761 | ERR("Filter reloc offset %u is not within data", |
2734ca65 CB |
762 | lum->u.filter.reloc_offset); |
763 | ret = -EINVAL; | |
764 | goto error; | |
765 | } | |
766 | ||
cd54f6d9 MD |
767 | bytecode = zmalloc(sizeof(*bytecode) + lum->u.filter.data_size); |
768 | if (!bytecode) { | |
769 | ret = -ENOMEM; | |
770 | goto error; | |
771 | } | |
f488575f | 772 | len = ustcomm_recv_unix_sock(sock, bytecode->bc.data, |
2d78951a MD |
773 | lum->u.filter.data_size); |
774 | switch (len) { | |
775 | case 0: /* orderly shutdown */ | |
776 | ret = 0; | |
cd54f6d9 | 777 | free(bytecode); |
2d78951a | 778 | goto error; |
2d78951a MD |
779 | default: |
780 | if (len == lum->u.filter.data_size) { | |
7bc53e94 | 781 | DBG("filter data received"); |
2d78951a | 782 | break; |
7bc53e94 MD |
783 | } else if (len < 0) { |
784 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
785 | if (len == -ECONNRESET) { | |
786 | ERR("%s remote end closed connection", sock_info->name); | |
787 | ret = len; | |
788 | free(bytecode); | |
789 | goto error; | |
790 | } | |
791 | ret = len; | |
eb8bf361 | 792 | free(bytecode); |
0dafcd63 | 793 | goto error; |
2d78951a | 794 | } else { |
7bc53e94 | 795 | DBG("incorrect filter data message size: %zd", len); |
2d78951a | 796 | ret = -EINVAL; |
cd54f6d9 | 797 | free(bytecode); |
0dafcd63 | 798 | goto error; |
2d78951a MD |
799 | } |
800 | } | |
f488575f MD |
801 | bytecode->bc.len = lum->u.filter.data_size; |
802 | bytecode->bc.reloc_offset = lum->u.filter.reloc_offset; | |
3f6fd224 | 803 | bytecode->bc.seqnum = lum->u.filter.seqnum; |
cd54f6d9 | 804 | if (ops->cmd) { |
2d78951a | 805 | ret = ops->cmd(lum->handle, lum->cmd, |
cd54f6d9 | 806 | (unsigned long) bytecode, |
f59ed768 | 807 | &args, sock_info); |
cd54f6d9 MD |
808 | if (ret) { |
809 | free(bytecode); | |
810 | } | |
811 | /* don't free bytecode if everything went fine. */ | |
812 | } else { | |
2d78951a | 813 | ret = -ENOSYS; |
cd54f6d9 MD |
814 | free(bytecode); |
815 | } | |
2d78951a MD |
816 | break; |
817 | } | |
86e36163 JI |
818 | case LTTNG_UST_EXCLUSION: |
819 | { | |
820 | /* Receive exclusion names */ | |
821 | struct lttng_ust_excluder_node *node; | |
822 | unsigned int count; | |
823 | ||
824 | count = lum->u.exclusion.count; | |
825 | if (count == 0) { | |
826 | /* There are no names to read */ | |
827 | ret = 0; | |
828 | goto error; | |
829 | } | |
830 | node = zmalloc(sizeof(*node) + | |
831 | count * LTTNG_UST_SYM_NAME_LEN); | |
832 | if (!node) { | |
833 | ret = -ENOMEM; | |
834 | goto error; | |
835 | } | |
836 | node->excluder.count = count; | |
837 | len = ustcomm_recv_unix_sock(sock, node->excluder.names, | |
838 | count * LTTNG_UST_SYM_NAME_LEN); | |
839 | switch (len) { | |
840 | case 0: /* orderly shutdown */ | |
841 | ret = 0; | |
842 | free(node); | |
843 | goto error; | |
844 | default: | |
845 | if (len == count * LTTNG_UST_SYM_NAME_LEN) { | |
846 | DBG("Exclusion data received"); | |
847 | break; | |
848 | } else if (len < 0) { | |
849 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
850 | if (len == -ECONNRESET) { | |
851 | ERR("%s remote end closed connection", sock_info->name); | |
852 | ret = len; | |
853 | free(node); | |
854 | goto error; | |
855 | } | |
856 | ret = len; | |
857 | free(node); | |
0dafcd63 | 858 | goto error; |
86e36163 JI |
859 | } else { |
860 | DBG("Incorrect exclusion data message size: %zd", len); | |
861 | ret = -EINVAL; | |
862 | free(node); | |
0dafcd63 | 863 | goto error; |
86e36163 JI |
864 | } |
865 | } | |
866 | if (ops->cmd) { | |
867 | ret = ops->cmd(lum->handle, lum->cmd, | |
868 | (unsigned long) node, | |
869 | &args, sock_info); | |
870 | if (ret) { | |
871 | free(node); | |
872 | } | |
873 | /* Don't free exclusion data if everything went fine. */ | |
874 | } else { | |
875 | ret = -ENOSYS; | |
876 | free(node); | |
877 | } | |
878 | break; | |
879 | } | |
74d81a6c MD |
880 | case LTTNG_UST_CHANNEL: |
881 | { | |
882 | void *chan_data; | |
ff0f5728 | 883 | int wakeup_fd; |
74d81a6c MD |
884 | |
885 | len = ustcomm_recv_channel_from_sessiond(sock, | |
ff0f5728 MD |
886 | &chan_data, lum->u.channel.len, |
887 | &wakeup_fd); | |
74d81a6c MD |
888 | switch (len) { |
889 | case 0: /* orderly shutdown */ | |
890 | ret = 0; | |
891 | goto error; | |
892 | default: | |
893 | if (len == lum->u.channel.len) { | |
894 | DBG("channel data received"); | |
895 | break; | |
896 | } else if (len < 0) { | |
897 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
898 | if (len == -ECONNRESET) { | |
899 | ERR("%s remote end closed connection", sock_info->name); | |
900 | ret = len; | |
901 | goto error; | |
902 | } | |
903 | ret = len; | |
0dafcd63 | 904 | goto error; |
74d81a6c MD |
905 | } else { |
906 | DBG("incorrect channel data message size: %zd", len); | |
907 | ret = -EINVAL; | |
0dafcd63 | 908 | goto error; |
74d81a6c MD |
909 | } |
910 | } | |
911 | args.channel.chan_data = chan_data; | |
ff0f5728 | 912 | args.channel.wakeup_fd = wakeup_fd; |
74d81a6c MD |
913 | if (ops->cmd) |
914 | ret = ops->cmd(lum->handle, lum->cmd, | |
915 | (unsigned long) &lum->u, | |
916 | &args, sock_info); | |
917 | else | |
918 | ret = -ENOSYS; | |
919 | break; | |
920 | } | |
921 | case LTTNG_UST_STREAM: | |
922 | { | |
923 | /* Receive shm_fd, wakeup_fd */ | |
924 | ret = ustcomm_recv_stream_from_sessiond(sock, | |
694f63ca | 925 | NULL, |
74d81a6c MD |
926 | &args.stream.shm_fd, |
927 | &args.stream.wakeup_fd); | |
928 | if (ret) { | |
0dafcd63 | 929 | goto error; |
74d81a6c | 930 | } |
d292c6e0 | 931 | |
74d81a6c MD |
932 | if (ops->cmd) |
933 | ret = ops->cmd(lum->handle, lum->cmd, | |
934 | (unsigned long) &lum->u, | |
935 | &args, sock_info); | |
936 | else | |
937 | ret = -ENOSYS; | |
938 | break; | |
939 | } | |
8e696cfa MD |
940 | case LTTNG_UST_CONTEXT: |
941 | switch (lum->u.context.ctx) { | |
942 | case LTTNG_UST_CONTEXT_APP_CONTEXT: | |
943 | { | |
944 | char *p; | |
945 | size_t ctxlen, recvlen; | |
946 | ||
947 | ctxlen = strlen("$app.") + lum->u.context.u.app_ctx.provider_name_len - 1 | |
948 | + strlen(":") + lum->u.context.u.app_ctx.ctx_name_len; | |
949 | if (ctxlen >= LTTNG_UST_SYM_NAME_LEN) { | |
950 | ERR("Application context string length size is too large: %zu bytes", | |
951 | ctxlen); | |
952 | ret = -EINVAL; | |
953 | goto error; | |
954 | } | |
955 | strcpy(ctxstr, "$app."); | |
956 | p = &ctxstr[strlen("$app.")]; | |
957 | recvlen = ctxlen - strlen("$app."); | |
958 | len = ustcomm_recv_unix_sock(sock, p, recvlen); | |
959 | switch (len) { | |
960 | case 0: /* orderly shutdown */ | |
961 | ret = 0; | |
962 | goto error; | |
963 | default: | |
964 | if (len == recvlen) { | |
965 | DBG("app context data received"); | |
966 | break; | |
967 | } else if (len < 0) { | |
968 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
969 | if (len == -ECONNRESET) { | |
970 | ERR("%s remote end closed connection", sock_info->name); | |
971 | ret = len; | |
972 | goto error; | |
973 | } | |
974 | ret = len; | |
975 | goto error; | |
976 | } else { | |
977 | DBG("incorrect app context data message size: %zd", len); | |
978 | ret = -EINVAL; | |
979 | goto error; | |
980 | } | |
981 | } | |
982 | /* Put : between provider and ctxname. */ | |
983 | p[lum->u.context.u.app_ctx.provider_name_len - 1] = ':'; | |
984 | args.app_context.ctxname = ctxstr; | |
985 | break; | |
986 | } | |
987 | default: | |
988 | break; | |
989 | } | |
990 | if (ops->cmd) { | |
991 | ret = ops->cmd(lum->handle, lum->cmd, | |
992 | (unsigned long) &lum->u, | |
993 | &args, sock_info); | |
994 | } else { | |
995 | ret = -ENOSYS; | |
996 | } | |
997 | break; | |
d9e99d10 | 998 | default: |
46050b1a MD |
999 | if (ops->cmd) |
1000 | ret = ops->cmd(lum->handle, lum->cmd, | |
ef9ff354 | 1001 | (unsigned long) &lum->u, |
f59ed768 | 1002 | &args, sock_info); |
46050b1a MD |
1003 | else |
1004 | ret = -ENOSYS; | |
1005 | break; | |
d9e99d10 | 1006 | } |
46050b1a | 1007 | |
46050b1a MD |
1008 | lur.handle = lum->handle; |
1009 | lur.cmd = lum->cmd; | |
1010 | lur.ret_val = ret; | |
1011 | if (ret >= 0) { | |
7bc53e94 | 1012 | lur.ret_code = LTTNG_UST_OK; |
46050b1a | 1013 | } else { |
7bc53e94 MD |
1014 | /* |
1015 | * Use -LTTNG_UST_ERR as wildcard for UST internal | |
1016 | * error that are not caused by the transport, except if | |
1017 | * we already have a more precise error message to | |
1018 | * report. | |
1019 | */ | |
64b2564e DG |
1020 | if (ret > -LTTNG_UST_ERR) { |
1021 | /* Translate code to UST error. */ | |
1022 | switch (ret) { | |
1023 | case -EEXIST: | |
1024 | lur.ret_code = -LTTNG_UST_ERR_EXIST; | |
1025 | break; | |
1026 | case -EINVAL: | |
1027 | lur.ret_code = -LTTNG_UST_ERR_INVAL; | |
1028 | break; | |
1029 | case -ENOENT: | |
1030 | lur.ret_code = -LTTNG_UST_ERR_NOENT; | |
1031 | break; | |
1032 | case -EPERM: | |
1033 | lur.ret_code = -LTTNG_UST_ERR_PERM; | |
1034 | break; | |
1035 | case -ENOSYS: | |
1036 | lur.ret_code = -LTTNG_UST_ERR_NOSYS; | |
1037 | break; | |
1038 | default: | |
1039 | lur.ret_code = -LTTNG_UST_ERR; | |
1040 | break; | |
1041 | } | |
1042 | } else { | |
7bc53e94 | 1043 | lur.ret_code = ret; |
64b2564e | 1044 | } |
46050b1a | 1045 | } |
e6ea14c5 MD |
1046 | if (ret >= 0) { |
1047 | switch (lum->cmd) { | |
e6ea14c5 MD |
1048 | case LTTNG_UST_TRACER_VERSION: |
1049 | lur.u.version = lum->u.version; | |
1050 | break; | |
1051 | case LTTNG_UST_TRACEPOINT_LIST_GET: | |
1052 | memcpy(&lur.u.tracepoint, &lum->u.tracepoint, sizeof(lur.u.tracepoint)); | |
1053 | break; | |
1054 | } | |
381c0f1e | 1055 | } |
74d81a6c | 1056 | DBG("Return value: %d", lur.ret_val); |
4c62d8d1 MD |
1057 | |
1058 | ust_unlock(); | |
1059 | ||
1060 | /* | |
1061 | * Performed delayed statedump operations outside of the UST | |
1062 | * lock. We need to take the dynamic loader lock before we take | |
1063 | * the UST lock internally within handle_pending_statedump(). | |
1064 | */ | |
1065 | handle_pending_statedump(sock_info); | |
1066 | ||
1067 | if (ust_lock()) { | |
1068 | ret = -LTTNG_UST_ERR_EXITING; | |
1069 | goto error; | |
1070 | } | |
1071 | ||
46050b1a | 1072 | ret = send_reply(sock, &lur); |
193183fb | 1073 | if (ret < 0) { |
7bc53e94 | 1074 | DBG("error sending reply"); |
193183fb MD |
1075 | goto error; |
1076 | } | |
46050b1a | 1077 | |
40003310 MD |
1078 | /* |
1079 | * LTTNG_UST_TRACEPOINT_FIELD_LIST_GET needs to send the field | |
1080 | * after the reply. | |
1081 | */ | |
7bc53e94 | 1082 | if (lur.ret_code == LTTNG_UST_OK) { |
40003310 MD |
1083 | switch (lum->cmd) { |
1084 | case LTTNG_UST_TRACEPOINT_FIELD_LIST_GET: | |
1085 | len = ustcomm_send_unix_sock(sock, | |
1086 | &args.field_list.entry, | |
1087 | sizeof(args.field_list.entry)); | |
7bc53e94 MD |
1088 | if (len < 0) { |
1089 | ret = len; | |
1090 | goto error; | |
1091 | } | |
40003310 | 1092 | if (len != sizeof(args.field_list.entry)) { |
7bc53e94 | 1093 | ret = -EINVAL; |
40003310 MD |
1094 | goto error; |
1095 | } | |
1096 | } | |
1097 | } | |
ef9ff354 | 1098 | |
381c0f1e | 1099 | error: |
17dfb34b | 1100 | ust_unlock(); |
d9e99d10 | 1101 | |
37dddb65 | 1102 | return ret; |
246be17e PW |
1103 | } |
1104 | ||
46050b1a | 1105 | static |
efe0de09 | 1106 | void cleanup_sock_info(struct sock_info *sock_info, int exiting) |
46050b1a MD |
1107 | { |
1108 | int ret; | |
1109 | ||
5b14aab3 MD |
1110 | if (sock_info->root_handle != -1) { |
1111 | ret = lttng_ust_objd_unref(sock_info->root_handle, 1); | |
1112 | if (ret) { | |
1113 | ERR("Error unref root handle"); | |
1114 | } | |
1115 | sock_info->root_handle = -1; | |
1116 | } | |
e85887ff GAPG |
1117 | sock_info->registration_done = 0; |
1118 | sock_info->initial_statedump_done = 0; | |
5b14aab3 MD |
1119 | |
1120 | /* | |
1121 | * wait_shm_mmap, socket and notify socket are used by listener | |
1122 | * threads outside of the ust lock, so we cannot tear them down | |
1123 | * ourselves, because we cannot join on these threads. Leave | |
1124 | * responsibility of cleaning up these resources to the OS | |
1125 | * process exit. | |
1126 | */ | |
1127 | if (exiting) | |
1128 | return; | |
1129 | ||
46050b1a | 1130 | if (sock_info->socket != -1) { |
e6973a89 | 1131 | ret = ustcomm_close_unix_sock(sock_info->socket); |
46050b1a | 1132 | if (ret) { |
32ce8569 | 1133 | ERR("Error closing ust cmd socket"); |
46050b1a MD |
1134 | } |
1135 | sock_info->socket = -1; | |
1136 | } | |
32ce8569 MD |
1137 | if (sock_info->notify_socket != -1) { |
1138 | ret = ustcomm_close_unix_sock(sock_info->notify_socket); | |
1139 | if (ret) { | |
1140 | ERR("Error closing ust notify socket"); | |
1141 | } | |
1142 | sock_info->notify_socket = -1; | |
1143 | } | |
5b14aab3 | 1144 | if (sock_info->wait_shm_mmap) { |
172d6b68 MD |
1145 | long page_size; |
1146 | ||
1147 | page_size = sysconf(_SC_PAGE_SIZE); | |
2657d1ba MD |
1148 | if (page_size <= 0) { |
1149 | if (!page_size) { | |
1150 | errno = EINVAL; | |
1151 | } | |
1152 | PERROR("Error in sysconf(_SC_PAGE_SIZE)"); | |
1153 | } else { | |
172d6b68 MD |
1154 | ret = munmap(sock_info->wait_shm_mmap, page_size); |
1155 | if (ret) { | |
1156 | ERR("Error unmapping wait shm"); | |
1157 | } | |
7fc90dca MD |
1158 | } |
1159 | sock_info->wait_shm_mmap = NULL; | |
1160 | } | |
1161 | } | |
1162 | ||
58d4b2a2 | 1163 | /* |
33bbeb90 MD |
1164 | * Using fork to set umask in the child process (not multi-thread safe). |
1165 | * We deal with the shm_open vs ftruncate race (happening when the | |
1166 | * sessiond owns the shm and does not let everybody modify it, to ensure | |
1167 | * safety against shm_unlink) by simply letting the mmap fail and | |
1168 | * retrying after a few seconds. | |
1169 | * For global shm, everybody has rw access to it until the sessiond | |
1170 | * starts. | |
58d4b2a2 | 1171 | */ |
7fc90dca | 1172 | static |
58d4b2a2 | 1173 | int get_wait_shm(struct sock_info *sock_info, size_t mmap_size) |
7fc90dca | 1174 | { |
7fc90dca | 1175 | int wait_shm_fd, ret; |
58d4b2a2 | 1176 | pid_t pid; |
44e073f5 | 1177 | |
58d4b2a2 | 1178 | /* |
33bbeb90 | 1179 | * Try to open read-only. |
58d4b2a2 | 1180 | */ |
33bbeb90 | 1181 | wait_shm_fd = shm_open(sock_info->wait_shm_path, O_RDONLY, 0); |
58d4b2a2 | 1182 | if (wait_shm_fd >= 0) { |
7aa76730 MD |
1183 | int32_t tmp_read; |
1184 | ssize_t len; | |
1185 | size_t bytes_read = 0; | |
1186 | ||
1187 | /* | |
1188 | * Try to read the fd. If unable to do so, try opening | |
1189 | * it in write mode. | |
1190 | */ | |
1191 | do { | |
1192 | len = read(wait_shm_fd, | |
1193 | &((char *) &tmp_read)[bytes_read], | |
1194 | sizeof(tmp_read) - bytes_read); | |
1195 | if (len > 0) { | |
1196 | bytes_read += len; | |
1197 | } | |
1198 | } while ((len < 0 && errno == EINTR) | |
1199 | || (len > 0 && bytes_read < sizeof(tmp_read))); | |
1200 | if (bytes_read != sizeof(tmp_read)) { | |
1201 | ret = close(wait_shm_fd); | |
1202 | if (ret) { | |
1203 | ERR("close wait_shm_fd"); | |
1204 | } | |
1205 | goto open_write; | |
1206 | } | |
58d4b2a2 MD |
1207 | goto end; |
1208 | } else if (wait_shm_fd < 0 && errno != ENOENT) { | |
1209 | /* | |
33bbeb90 MD |
1210 | * Real-only open did not work, and it's not because the |
1211 | * entry was not present. It's a failure that prohibits | |
1212 | * using shm. | |
58d4b2a2 | 1213 | */ |
7fc90dca | 1214 | ERR("Error opening shm %s", sock_info->wait_shm_path); |
58d4b2a2 | 1215 | goto end; |
7fc90dca | 1216 | } |
7aa76730 MD |
1217 | |
1218 | open_write: | |
7fc90dca | 1219 | /* |
7aa76730 MD |
1220 | * If the open failed because the file did not exist, or because |
1221 | * the file was not truncated yet, try creating it ourself. | |
7fc90dca | 1222 | */ |
8c90a710 | 1223 | URCU_TLS(lttng_ust_nest_count)++; |
58d4b2a2 | 1224 | pid = fork(); |
8c90a710 | 1225 | URCU_TLS(lttng_ust_nest_count)--; |
58d4b2a2 MD |
1226 | if (pid > 0) { |
1227 | int status; | |
1228 | ||
1229 | /* | |
1230 | * Parent: wait for child to return, in which case the | |
1231 | * shared memory map will have been created. | |
1232 | */ | |
1233 | pid = wait(&status); | |
b7d3cb32 | 1234 | if (pid < 0 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) { |
58d4b2a2 MD |
1235 | wait_shm_fd = -1; |
1236 | goto end; | |
7fc90dca | 1237 | } |
58d4b2a2 MD |
1238 | /* |
1239 | * Try to open read-only again after creation. | |
1240 | */ | |
33bbeb90 | 1241 | wait_shm_fd = shm_open(sock_info->wait_shm_path, O_RDONLY, 0); |
58d4b2a2 MD |
1242 | if (wait_shm_fd < 0) { |
1243 | /* | |
1244 | * Real-only open did not work. It's a failure | |
1245 | * that prohibits using shm. | |
1246 | */ | |
1247 | ERR("Error opening shm %s", sock_info->wait_shm_path); | |
1248 | goto end; | |
1249 | } | |
1250 | goto end; | |
1251 | } else if (pid == 0) { | |
1252 | int create_mode; | |
1253 | ||
1254 | /* Child */ | |
33bbeb90 | 1255 | create_mode = S_IRUSR | S_IWUSR | S_IRGRP; |
58d4b2a2 | 1256 | if (sock_info->global) |
33bbeb90 | 1257 | create_mode |= S_IROTH | S_IWGRP | S_IWOTH; |
58d4b2a2 MD |
1258 | /* |
1259 | * We're alone in a child process, so we can modify the | |
1260 | * process-wide umask. | |
1261 | */ | |
33bbeb90 | 1262 | umask(~create_mode); |
58d4b2a2 | 1263 | /* |
33bbeb90 MD |
1264 | * Try creating shm (or get rw access). |
1265 | * We don't do an exclusive open, because we allow other | |
1266 | * processes to create+ftruncate it concurrently. | |
58d4b2a2 MD |
1267 | */ |
1268 | wait_shm_fd = shm_open(sock_info->wait_shm_path, | |
1269 | O_RDWR | O_CREAT, create_mode); | |
1270 | if (wait_shm_fd >= 0) { | |
1271 | ret = ftruncate(wait_shm_fd, mmap_size); | |
1272 | if (ret) { | |
1273 | PERROR("ftruncate"); | |
b0c1425d | 1274 | _exit(EXIT_FAILURE); |
58d4b2a2 | 1275 | } |
b0c1425d | 1276 | _exit(EXIT_SUCCESS); |
58d4b2a2 | 1277 | } |
33bbeb90 MD |
1278 | /* |
1279 | * For local shm, we need to have rw access to accept | |
1280 | * opening it: this means the local sessiond will be | |
1281 | * able to wake us up. For global shm, we open it even | |
1282 | * if rw access is not granted, because the root.root | |
1283 | * sessiond will be able to override all rights and wake | |
1284 | * us up. | |
1285 | */ | |
1286 | if (!sock_info->global && errno != EACCES) { | |
58d4b2a2 | 1287 | ERR("Error opening shm %s", sock_info->wait_shm_path); |
5d3bc5ed | 1288 | _exit(EXIT_FAILURE); |
58d4b2a2 MD |
1289 | } |
1290 | /* | |
33bbeb90 MD |
1291 | * The shm exists, but we cannot open it RW. Report |
1292 | * success. | |
58d4b2a2 | 1293 | */ |
5d3bc5ed | 1294 | _exit(EXIT_SUCCESS); |
58d4b2a2 MD |
1295 | } else { |
1296 | return -1; | |
7fc90dca | 1297 | } |
58d4b2a2 | 1298 | end: |
33bbeb90 MD |
1299 | if (wait_shm_fd >= 0 && !sock_info->global) { |
1300 | struct stat statbuf; | |
1301 | ||
1302 | /* | |
1303 | * Ensure that our user is the owner of the shm file for | |
1304 | * local shm. If we do not own the file, it means our | |
1305 | * sessiond will not have access to wake us up (there is | |
1306 | * probably a rogue process trying to fake our | |
1307 | * sessiond). Fallback to polling method in this case. | |
1308 | */ | |
1309 | ret = fstat(wait_shm_fd, &statbuf); | |
1310 | if (ret) { | |
1311 | PERROR("fstat"); | |
1312 | goto error_close; | |
1313 | } | |
1314 | if (statbuf.st_uid != getuid()) | |
1315 | goto error_close; | |
1316 | } | |
58d4b2a2 | 1317 | return wait_shm_fd; |
33bbeb90 MD |
1318 | |
1319 | error_close: | |
1320 | ret = close(wait_shm_fd); | |
1321 | if (ret) { | |
1322 | PERROR("Error closing fd"); | |
1323 | } | |
1324 | return -1; | |
58d4b2a2 MD |
1325 | } |
1326 | ||
1327 | static | |
1328 | char *get_map_shm(struct sock_info *sock_info) | |
1329 | { | |
172d6b68 | 1330 | long page_size; |
58d4b2a2 MD |
1331 | int wait_shm_fd, ret; |
1332 | char *wait_shm_mmap; | |
1333 | ||
172d6b68 | 1334 | page_size = sysconf(_SC_PAGE_SIZE); |
2657d1ba MD |
1335 | if (page_size <= 0) { |
1336 | if (!page_size) { | |
1337 | errno = EINVAL; | |
1338 | } | |
1339 | PERROR("Error in sysconf(_SC_PAGE_SIZE)"); | |
172d6b68 MD |
1340 | goto error; |
1341 | } | |
1342 | ||
6548fca4 | 1343 | lttng_ust_lock_fd_tracker(); |
172d6b68 | 1344 | wait_shm_fd = get_wait_shm(sock_info, page_size); |
58d4b2a2 | 1345 | if (wait_shm_fd < 0) { |
6548fca4 | 1346 | lttng_ust_unlock_fd_tracker(); |
58d4b2a2 | 1347 | goto error; |
44e073f5 | 1348 | } |
f5c453e9 JR |
1349 | |
1350 | ret = lttng_ust_add_fd_to_tracker(wait_shm_fd); | |
1351 | if (ret < 0) { | |
1352 | ret = close(wait_shm_fd); | |
1353 | if (!ret) { | |
1354 | PERROR("Error closing fd"); | |
1355 | } | |
1356 | lttng_ust_unlock_fd_tracker(); | |
1357 | goto error; | |
1358 | } | |
1359 | ||
1360 | wait_shm_fd = ret; | |
6548fca4 MD |
1361 | lttng_ust_unlock_fd_tracker(); |
1362 | ||
172d6b68 | 1363 | wait_shm_mmap = mmap(NULL, page_size, PROT_READ, |
7fc90dca | 1364 | MAP_SHARED, wait_shm_fd, 0); |
6548fca4 | 1365 | |
7fc90dca | 1366 | /* close shm fd immediately after taking the mmap reference */ |
6548fca4 | 1367 | lttng_ust_lock_fd_tracker(); |
7fc90dca | 1368 | ret = close(wait_shm_fd); |
6548fca4 MD |
1369 | if (!ret) { |
1370 | lttng_ust_delete_fd_from_tracker(wait_shm_fd); | |
1371 | } else { | |
33bbeb90 MD |
1372 | PERROR("Error closing fd"); |
1373 | } | |
6548fca4 MD |
1374 | lttng_ust_unlock_fd_tracker(); |
1375 | ||
33bbeb90 MD |
1376 | if (wait_shm_mmap == MAP_FAILED) { |
1377 | DBG("mmap error (can be caused by race with sessiond). Fallback to poll mode."); | |
1378 | goto error; | |
7fc90dca MD |
1379 | } |
1380 | return wait_shm_mmap; | |
1381 | ||
1382 | error: | |
1383 | return NULL; | |
1384 | } | |
1385 | ||
1386 | static | |
1387 | void wait_for_sessiond(struct sock_info *sock_info) | |
1388 | { | |
9d2dfb47 | 1389 | /* Use ust_lock to check if we should quit. */ |
3327ac33 | 1390 | if (ust_lock()) { |
7fc90dca MD |
1391 | goto quit; |
1392 | } | |
37ed587a MD |
1393 | if (wait_poll_fallback) { |
1394 | goto error; | |
1395 | } | |
7fc90dca MD |
1396 | ust_unlock(); |
1397 | ||
9d2dfb47 JR |
1398 | assert(sock_info->wait_shm_mmap); |
1399 | ||
7fc90dca | 1400 | DBG("Waiting for %s apps sessiond", sock_info->name); |
80e2814b | 1401 | /* Wait for futex wakeup */ |
ee7fcec8 MD |
1402 | if (uatomic_read((int32_t *) sock_info->wait_shm_mmap)) |
1403 | goto end_wait; | |
1404 | ||
1405 | while (futex_async((int32_t *) sock_info->wait_shm_mmap, | |
1406 | FUTEX_WAIT, 0, NULL, NULL, 0)) { | |
1407 | switch (errno) { | |
1408 | case EWOULDBLOCK: | |
1409 | /* Value already changed. */ | |
1410 | goto end_wait; | |
1411 | case EINTR: | |
1412 | /* Retry if interrupted by signal. */ | |
1413 | break; /* Get out of switch. */ | |
1414 | case EFAULT: | |
1415 | wait_poll_fallback = 1; | |
1416 | DBG( | |
37ed587a MD |
1417 | "Linux kernels 2.6.33 to 3.0 (with the exception of stable versions) " |
1418 | "do not support FUTEX_WAKE on read-only memory mappings correctly. " | |
1419 | "Please upgrade your kernel " | |
1420 | "(fix is commit 9ea71503a8ed9184d2d0b8ccc4d269d05f7940ae in Linux kernel " | |
1421 | "mainline). LTTng-UST will use polling mode fallback."); | |
ee7fcec8 MD |
1422 | if (ust_debug()) |
1423 | PERROR("futex"); | |
1424 | goto end_wait; | |
80e2814b MD |
1425 | } |
1426 | } | |
ee7fcec8 | 1427 | end_wait: |
7fc90dca MD |
1428 | return; |
1429 | ||
1430 | quit: | |
1431 | ust_unlock(); | |
1432 | return; | |
1433 | ||
1434 | error: | |
1435 | ust_unlock(); | |
7fc90dca | 1436 | return; |
46050b1a MD |
1437 | } |
1438 | ||
1ea11eab MD |
1439 | /* |
1440 | * This thread does not allocate any resource, except within | |
1441 | * handle_message, within mutex protection. This mutex protects against | |
1442 | * fork and exit. | |
98bf993f | 1443 | * The other moment it allocates resources is at socket connection, which |
1ea11eab MD |
1444 | * is also protected by the mutex. |
1445 | */ | |
d9e99d10 MD |
1446 | static |
1447 | void *ust_listener_thread(void *arg) | |
1448 | { | |
1ea11eab | 1449 | struct sock_info *sock_info = arg; |
f5c453e9 | 1450 | int sock, ret, prev_connect_failed = 0, has_waited = 0, fd; |
ff517991 | 1451 | long timeout; |
d9e99d10 | 1452 | |
c362addf | 1453 | lttng_ust_fixup_tls(); |
01f0e40c RB |
1454 | /* |
1455 | * If available, add '-ust' to the end of this thread's | |
1456 | * process name | |
1457 | */ | |
1458 | ret = lttng_ust_setustprocname(); | |
1459 | if (ret) { | |
1460 | ERR("Unable to set UST process name"); | |
1461 | } | |
1462 | ||
9eb62b9c MD |
1463 | /* Restart trying to connect to the session daemon */ |
1464 | restart: | |
c0eedf81 MD |
1465 | if (prev_connect_failed) { |
1466 | /* Wait for sessiond availability with pipe */ | |
1467 | wait_for_sessiond(sock_info); | |
1468 | if (has_waited) { | |
1469 | has_waited = 0; | |
1470 | /* | |
1471 | * Sleep for 5 seconds before retrying after a | |
1472 | * sequence of failure / wait / failure. This | |
1473 | * deals with a killed or broken session daemon. | |
1474 | */ | |
1475 | sleep(5); | |
eacc4aa4 MD |
1476 | } else { |
1477 | has_waited = 1; | |
c0eedf81 | 1478 | } |
c0eedf81 MD |
1479 | prev_connect_failed = 0; |
1480 | } | |
9eb62b9c | 1481 | |
101dace0 JR |
1482 | if (ust_lock()) { |
1483 | goto quit; | |
1484 | } | |
1485 | ||
1ea11eab | 1486 | if (sock_info->socket != -1) { |
6548fca4 | 1487 | /* FD tracker is updated by ustcomm_close_unix_sock() */ |
e6973a89 | 1488 | ret = ustcomm_close_unix_sock(sock_info->socket); |
1ea11eab | 1489 | if (ret) { |
32ce8569 MD |
1490 | ERR("Error closing %s ust cmd socket", |
1491 | sock_info->name); | |
1ea11eab MD |
1492 | } |
1493 | sock_info->socket = -1; | |
1494 | } | |
32ce8569 | 1495 | if (sock_info->notify_socket != -1) { |
6548fca4 | 1496 | /* FD tracker is updated by ustcomm_close_unix_sock() */ |
32ce8569 MD |
1497 | ret = ustcomm_close_unix_sock(sock_info->notify_socket); |
1498 | if (ret) { | |
1499 | ERR("Error closing %s ust notify socket", | |
1500 | sock_info->name); | |
1501 | } | |
1502 | sock_info->notify_socket = -1; | |
1503 | } | |
46050b1a | 1504 | |
6548fca4 | 1505 | |
321f2351 MD |
1506 | /* |
1507 | * Register. We need to perform both connect and sending | |
1508 | * registration message before doing the next connect otherwise | |
1509 | * we may reach unix socket connect queue max limits and block | |
1510 | * on the 2nd connect while the session daemon is awaiting the | |
1511 | * first connect registration message. | |
1512 | */ | |
1513 | /* Connect cmd socket */ | |
6548fca4 | 1514 | lttng_ust_lock_fd_tracker(); |
451d66b2 MD |
1515 | ret = ustcomm_connect_unix_sock(sock_info->sock_path, |
1516 | get_connect_sock_timeout()); | |
321f2351 | 1517 | if (ret < 0) { |
6548fca4 | 1518 | lttng_ust_unlock_fd_tracker(); |
321f2351 MD |
1519 | DBG("Info: sessiond not accepting connections to %s apps socket", sock_info->name); |
1520 | prev_connect_failed = 1; | |
5b14aab3 | 1521 | |
e3426ddc | 1522 | /* |
321f2351 MD |
1523 | * If we cannot find the sessiond daemon, don't delay |
1524 | * constructor execution. | |
e3426ddc | 1525 | */ |
e85887ff | 1526 | ret = handle_register_failed(sock_info); |
321f2351 MD |
1527 | assert(!ret); |
1528 | ust_unlock(); | |
1529 | goto restart; | |
27fe9f21 | 1530 | } |
f5c453e9 JR |
1531 | fd = ret; |
1532 | ret = lttng_ust_add_fd_to_tracker(fd); | |
1533 | if (ret < 0) { | |
1534 | ret = close(fd); | |
1535 | if (ret) { | |
1536 | PERROR("close on sock_info->socket"); | |
1537 | } | |
1538 | ret = -1; | |
1539 | lttng_ust_unlock_fd_tracker(); | |
1540 | ust_unlock(); | |
1541 | goto quit; | |
1542 | } | |
1543 | ||
321f2351 | 1544 | sock_info->socket = ret; |
f5c453e9 | 1545 | lttng_ust_unlock_fd_tracker(); |
27fe9f21 | 1546 | |
6548fca4 MD |
1547 | ust_unlock(); |
1548 | /* | |
1549 | * Unlock/relock ust lock because connect is blocking (with | |
1550 | * timeout). Don't delay constructors on the ust lock for too | |
1551 | * long. | |
1552 | */ | |
3327ac33 | 1553 | if (ust_lock()) { |
5b14aab3 MD |
1554 | goto quit; |
1555 | } | |
1556 | ||
46050b1a MD |
1557 | /* |
1558 | * Create only one root handle per listener thread for the whole | |
f59ed768 MD |
1559 | * process lifetime, so we ensure we get ID which is statically |
1560 | * assigned to the root handle. | |
46050b1a MD |
1561 | */ |
1562 | if (sock_info->root_handle == -1) { | |
1563 | ret = lttng_abi_create_root_handle(); | |
a51070bb | 1564 | if (ret < 0) { |
46050b1a | 1565 | ERR("Error creating root handle"); |
46050b1a MD |
1566 | goto quit; |
1567 | } | |
1568 | sock_info->root_handle = ret; | |
9eb62b9c | 1569 | } |
1ea11eab | 1570 | |
32ce8569 | 1571 | ret = register_to_sessiond(sock_info->socket, USTCTL_SOCKET_CMD); |
9eb62b9c | 1572 | if (ret < 0) { |
32ce8569 MD |
1573 | ERR("Error registering to %s ust cmd socket", |
1574 | sock_info->name); | |
c0eedf81 | 1575 | prev_connect_failed = 1; |
11ff9c7d MD |
1576 | /* |
1577 | * If we cannot register to the sessiond daemon, don't | |
1578 | * delay constructor execution. | |
1579 | */ | |
e85887ff | 1580 | ret = handle_register_failed(sock_info); |
11ff9c7d | 1581 | assert(!ret); |
17dfb34b | 1582 | ust_unlock(); |
9eb62b9c MD |
1583 | goto restart; |
1584 | } | |
321f2351 MD |
1585 | |
1586 | ust_unlock(); | |
6548fca4 MD |
1587 | /* |
1588 | * Unlock/relock ust lock because connect is blocking (with | |
1589 | * timeout). Don't delay constructors on the ust lock for too | |
1590 | * long. | |
1591 | */ | |
1592 | if (ust_lock()) { | |
1593 | goto quit; | |
1594 | } | |
321f2351 MD |
1595 | |
1596 | /* Connect notify socket */ | |
6548fca4 | 1597 | lttng_ust_lock_fd_tracker(); |
451d66b2 MD |
1598 | ret = ustcomm_connect_unix_sock(sock_info->sock_path, |
1599 | get_connect_sock_timeout()); | |
321f2351 | 1600 | if (ret < 0) { |
6548fca4 | 1601 | lttng_ust_unlock_fd_tracker(); |
321f2351 MD |
1602 | DBG("Info: sessiond not accepting connections to %s apps socket", sock_info->name); |
1603 | prev_connect_failed = 1; | |
1604 | ||
321f2351 MD |
1605 | /* |
1606 | * If we cannot find the sessiond daemon, don't delay | |
1607 | * constructor execution. | |
1608 | */ | |
e85887ff | 1609 | ret = handle_register_failed(sock_info); |
321f2351 MD |
1610 | assert(!ret); |
1611 | ust_unlock(); | |
1612 | goto restart; | |
1613 | } | |
f5c453e9 JR |
1614 | |
1615 | fd = ret; | |
1616 | ret = lttng_ust_add_fd_to_tracker(fd); | |
1617 | if (ret < 0) { | |
1618 | ret = close(fd); | |
1619 | if (ret) { | |
1620 | PERROR("close on sock_info->notify_socket"); | |
1621 | } | |
1622 | ret = -1; | |
1623 | lttng_ust_unlock_fd_tracker(); | |
1624 | ust_unlock(); | |
1625 | goto quit; | |
1626 | } | |
1627 | ||
321f2351 | 1628 | sock_info->notify_socket = ret; |
f5c453e9 | 1629 | lttng_ust_unlock_fd_tracker(); |
321f2351 | 1630 | |
6548fca4 MD |
1631 | ust_unlock(); |
1632 | /* | |
1633 | * Unlock/relock ust lock because connect is blocking (with | |
1634 | * timeout). Don't delay constructors on the ust lock for too | |
1635 | * long. | |
1636 | */ | |
1637 | if (ust_lock()) { | |
1638 | goto quit; | |
1639 | } | |
1640 | ||
321f2351 MD |
1641 | timeout = get_notify_sock_timeout(); |
1642 | if (timeout >= 0) { | |
1643 | /* | |
1644 | * Give at least 10ms to sessiond to reply to | |
1645 | * notifications. | |
1646 | */ | |
1647 | if (timeout < 10) | |
1648 | timeout = 10; | |
1649 | ret = ustcomm_setsockopt_rcv_timeout(sock_info->notify_socket, | |
1650 | timeout); | |
1651 | if (ret < 0) { | |
1652 | WARN("Error setting socket receive timeout"); | |
1653 | } | |
1654 | ret = ustcomm_setsockopt_snd_timeout(sock_info->notify_socket, | |
1655 | timeout); | |
1656 | if (ret < 0) { | |
1657 | WARN("Error setting socket send timeout"); | |
1658 | } | |
1659 | } else if (timeout < -1) { | |
1660 | WARN("Unsupported timeout value %ld", timeout); | |
1661 | } | |
1662 | ||
32ce8569 MD |
1663 | ret = register_to_sessiond(sock_info->notify_socket, |
1664 | USTCTL_SOCKET_NOTIFY); | |
1665 | if (ret < 0) { | |
1666 | ERR("Error registering to %s ust notify socket", | |
1667 | sock_info->name); | |
1668 | prev_connect_failed = 1; | |
1669 | /* | |
1670 | * If we cannot register to the sessiond daemon, don't | |
1671 | * delay constructor execution. | |
1672 | */ | |
e85887ff | 1673 | ret = handle_register_failed(sock_info); |
32ce8569 MD |
1674 | assert(!ret); |
1675 | ust_unlock(); | |
1676 | goto restart; | |
1677 | } | |
1678 | sock = sock_info->socket; | |
1679 | ||
17dfb34b | 1680 | ust_unlock(); |
46050b1a | 1681 | |
d9e99d10 MD |
1682 | for (;;) { |
1683 | ssize_t len; | |
57773204 | 1684 | struct ustcomm_ust_msg lum; |
d9e99d10 | 1685 | |
57773204 | 1686 | len = ustcomm_recv_unix_sock(sock, &lum, sizeof(lum)); |
d9e99d10 MD |
1687 | switch (len) { |
1688 | case 0: /* orderly shutdown */ | |
7dd08bec | 1689 | DBG("%s lttng-sessiond has performed an orderly shutdown", sock_info->name); |
3327ac33 | 1690 | if (ust_lock()) { |
d5e1fea6 MD |
1691 | goto quit; |
1692 | } | |
8236ba10 MD |
1693 | /* |
1694 | * Either sessiond has shutdown or refused us by closing the socket. | |
1695 | * In either case, we don't want to delay construction execution, | |
1696 | * and we need to wait before retry. | |
1697 | */ | |
1698 | prev_connect_failed = 1; | |
1699 | /* | |
1700 | * If we cannot register to the sessiond daemon, don't | |
1701 | * delay constructor execution. | |
1702 | */ | |
e85887ff | 1703 | ret = handle_register_failed(sock_info); |
8236ba10 MD |
1704 | assert(!ret); |
1705 | ust_unlock(); | |
d9e99d10 | 1706 | goto end; |
e7723462 | 1707 | case sizeof(lum): |
74d81a6c | 1708 | print_cmd(lum.cmd, lum.handle); |
11ff9c7d | 1709 | ret = handle_message(sock_info, sock, &lum); |
7bc53e94 | 1710 | if (ret) { |
0dafcd63 MD |
1711 | ERR("Error handling message for %s socket", |
1712 | sock_info->name); | |
1713 | /* | |
1714 | * Close socket if protocol error is | |
1715 | * detected. | |
1716 | */ | |
1717 | goto end; | |
d9e99d10 MD |
1718 | } |
1719 | continue; | |
7bc53e94 MD |
1720 | default: |
1721 | if (len < 0) { | |
1722 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
1723 | } else { | |
1724 | DBG("incorrect message size (%s socket): %zd", sock_info->name, len); | |
1725 | } | |
1726 | if (len == -ECONNRESET) { | |
1727 | DBG("%s remote end closed connection", sock_info->name); | |
d9e99d10 MD |
1728 | goto end; |
1729 | } | |
1730 | goto end; | |
d9e99d10 MD |
1731 | } |
1732 | ||
1733 | } | |
1734 | end: | |
3327ac33 | 1735 | if (ust_lock()) { |
d5e1fea6 MD |
1736 | goto quit; |
1737 | } | |
f59ed768 MD |
1738 | /* Cleanup socket handles before trying to reconnect */ |
1739 | lttng_ust_objd_table_owner_cleanup(sock_info); | |
1740 | ust_unlock(); | |
9eb62b9c | 1741 | goto restart; /* try to reconnect */ |
e33f3265 | 1742 | |
1ea11eab | 1743 | quit: |
e33f3265 | 1744 | ust_unlock(); |
3327ac33 MD |
1745 | |
1746 | pthread_mutex_lock(&ust_exit_mutex); | |
1747 | sock_info->thread_active = 0; | |
1748 | pthread_mutex_unlock(&ust_exit_mutex); | |
d9e99d10 MD |
1749 | return NULL; |
1750 | } | |
1751 | ||
2594a5b4 MD |
1752 | /* |
1753 | * Weak symbol to call when the ust malloc wrapper is not loaded. | |
1754 | */ | |
1755 | __attribute__((weak)) | |
1756 | void lttng_ust_malloc_wrapper_init(void) | |
1757 | { | |
1758 | } | |
1759 | ||
2691221a MD |
1760 | /* |
1761 | * sessiond monitoring thread: monitor presence of global and per-user | |
1762 | * sessiond by polling the application common named pipe. | |
1763 | */ | |
edaa1431 | 1764 | void __attribute__((constructor)) lttng_ust_init(void) |
2691221a | 1765 | { |
11ff9c7d | 1766 | struct timespec constructor_timeout; |
ae6a58bf | 1767 | sigset_t sig_all_blocked, orig_parent_mask; |
1879f67f | 1768 | pthread_attr_t thread_attr; |
cf12a773 | 1769 | int timeout_mode; |
2691221a | 1770 | int ret; |
b2292d85 | 1771 | void *handle; |
2691221a | 1772 | |
edaa1431 MD |
1773 | if (uatomic_xchg(&initialized, 1) == 1) |
1774 | return; | |
1775 | ||
eddd8d5d MD |
1776 | /* |
1777 | * Fixup interdependency between TLS fixup mutex (which happens | |
1778 | * to be the dynamic linker mutex) and ust_lock, taken within | |
1779 | * the ust lock. | |
1780 | */ | |
c362addf | 1781 | lttng_ust_fixup_tls(); |
eddd8d5d | 1782 | |
07b57e5e MD |
1783 | lttng_ust_loaded = 1; |
1784 | ||
b2292d85 FD |
1785 | /* |
1786 | * We need to ensure that the liblttng-ust library is not unloaded to avoid | |
1787 | * the unloading of code used by the ust_listener_threads as we can not | |
1788 | * reliably know when they exited. To do that, manually load | |
1789 | * liblttng-ust.so to increment the dynamic loader's internal refcount for | |
1790 | * this library so it never becomes zero, thus never gets unloaded from the | |
1791 | * address space of the process. Since we are already running in the | |
1792 | * constructor of the LTTNG_UST_LIB_SO_NAME library, calling dlopen will | |
1793 | * simply increment the refcount and no additionnal work is needed by the | |
1794 | * dynamic loader as the shared library is already loaded in the address | |
1795 | * space. As a safe guard, we use the RTLD_NODELETE flag to prevent | |
1796 | * unloading of the UST library if its refcount becomes zero (which should | |
1797 | * never happen). Do the return value check but discard the handle at the | |
1798 | * end of the function as it's not needed. | |
1799 | */ | |
1800 | handle = dlopen(LTTNG_UST_LIB_SO_NAME, RTLD_LAZY | RTLD_NODELETE); | |
1801 | if (!handle) { | |
1802 | ERR("dlopen of liblttng-ust shared library (%s).", LTTNG_UST_LIB_SO_NAME); | |
1803 | } | |
1804 | ||
edaa1431 MD |
1805 | /* |
1806 | * We want precise control over the order in which we construct | |
1807 | * our sub-libraries vs starting to receive commands from | |
1808 | * sessiond (otherwise leading to errors when trying to create | |
1809 | * sessiond before the init functions are completed). | |
1810 | */ | |
2691221a | 1811 | init_usterr(); |
6f626d28 | 1812 | lttng_ust_getenv_init(); /* Needs init_usterr() to be completed. */ |
edaa1431 | 1813 | init_tracepoint(); |
6548fca4 | 1814 | lttng_ust_init_fd_tracker(); |
f9364363 | 1815 | lttng_ust_clock_init(); |
5e1b7b8b | 1816 | lttng_ust_getcpu_init(); |
cf73e0fe | 1817 | lttng_ust_statedump_init(); |
7dd08bec MD |
1818 | lttng_ring_buffer_metadata_client_init(); |
1819 | lttng_ring_buffer_client_overwrite_init(); | |
34a91bdb | 1820 | lttng_ring_buffer_client_overwrite_rt_init(); |
7dd08bec | 1821 | lttng_ring_buffer_client_discard_init(); |
34a91bdb | 1822 | lttng_ring_buffer_client_discard_rt_init(); |
d58d1454 | 1823 | lttng_perf_counter_init(); |
2594a5b4 MD |
1824 | /* |
1825 | * Invoke ust malloc wrapper init before starting other threads. | |
1826 | */ | |
1827 | lttng_ust_malloc_wrapper_init(); | |
2691221a | 1828 | |
ff517991 | 1829 | timeout_mode = get_constructor_timeout(&constructor_timeout); |
11ff9c7d | 1830 | |
b2c5f61a | 1831 | get_allow_blocking(); |
6f97f9c2 | 1832 | |
95259bd0 | 1833 | ret = sem_init(&constructor_wait, 0, 0); |
8aadb54a MD |
1834 | if (ret) { |
1835 | PERROR("sem_init"); | |
1836 | } | |
11ff9c7d | 1837 | |
9d2dfb47 JR |
1838 | ret = setup_global_apps(); |
1839 | if (ret) { | |
1840 | assert(global_apps.allowed == 0); | |
1841 | DBG("global apps setup returned %d", ret); | |
1842 | } | |
1843 | ||
8d20bf54 | 1844 | ret = setup_local_apps(); |
2691221a | 1845 | if (ret) { |
9d2dfb47 | 1846 | assert(local_apps.allowed == 0); |
9ec6895c | 1847 | DBG("local apps setup returned %d", ret); |
2691221a | 1848 | } |
ae6a58bf WP |
1849 | |
1850 | /* A new thread created by pthread_create inherits the signal mask | |
1851 | * from the parent. To avoid any signal being received by the | |
1852 | * listener thread, we block all signals temporarily in the parent, | |
1853 | * while we create the listener thread. | |
1854 | */ | |
1855 | sigfillset(&sig_all_blocked); | |
1856 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_parent_mask); | |
1857 | if (ret) { | |
d94d802c | 1858 | ERR("pthread_sigmask: %s", strerror(ret)); |
ae6a58bf WP |
1859 | } |
1860 | ||
1879f67f MG |
1861 | ret = pthread_attr_init(&thread_attr); |
1862 | if (ret) { | |
1863 | ERR("pthread_attr_init: %s", strerror(ret)); | |
1864 | } | |
1865 | ret = pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED); | |
1866 | if (ret) { | |
1867 | ERR("pthread_attr_setdetachstate: %s", strerror(ret)); | |
1868 | } | |
1869 | ||
9d2dfb47 JR |
1870 | if (global_apps.allowed) { |
1871 | pthread_mutex_lock(&ust_exit_mutex); | |
1872 | ret = pthread_create(&global_apps.ust_listener, &thread_attr, | |
1873 | ust_listener_thread, &global_apps); | |
1874 | if (ret) { | |
1875 | ERR("pthread_create global: %s", strerror(ret)); | |
1876 | } | |
1877 | global_apps.thread_active = 1; | |
1878 | pthread_mutex_unlock(&ust_exit_mutex); | |
1879 | } else { | |
1880 | handle_register_done(&global_apps); | |
d94d802c | 1881 | } |
e33f3265 | 1882 | |
8d20bf54 | 1883 | if (local_apps.allowed) { |
c0bbbd5a | 1884 | pthread_mutex_lock(&ust_exit_mutex); |
1879f67f | 1885 | ret = pthread_create(&local_apps.ust_listener, &thread_attr, |
dde70ea0 | 1886 | ust_listener_thread, &local_apps); |
d94d802c MD |
1887 | if (ret) { |
1888 | ERR("pthread_create local: %s", strerror(ret)); | |
1889 | } | |
e33f3265 | 1890 | local_apps.thread_active = 1; |
c0bbbd5a | 1891 | pthread_mutex_unlock(&ust_exit_mutex); |
8d20bf54 MD |
1892 | } else { |
1893 | handle_register_done(&local_apps); | |
1894 | } | |
1879f67f MG |
1895 | ret = pthread_attr_destroy(&thread_attr); |
1896 | if (ret) { | |
1897 | ERR("pthread_attr_destroy: %s", strerror(ret)); | |
1898 | } | |
8d20bf54 | 1899 | |
ae6a58bf WP |
1900 | /* Restore original signal mask in parent */ |
1901 | ret = pthread_sigmask(SIG_SETMASK, &orig_parent_mask, NULL); | |
1902 | if (ret) { | |
d94d802c | 1903 | ERR("pthread_sigmask: %s", strerror(ret)); |
ae6a58bf WP |
1904 | } |
1905 | ||
cf12a773 MD |
1906 | switch (timeout_mode) { |
1907 | case 1: /* timeout wait */ | |
95259bd0 MD |
1908 | do { |
1909 | ret = sem_timedwait(&constructor_wait, | |
1910 | &constructor_timeout); | |
1911 | } while (ret < 0 && errno == EINTR); | |
8aadb54a MD |
1912 | if (ret < 0) { |
1913 | switch (errno) { | |
1914 | case ETIMEDOUT: | |
1915 | ERR("Timed out waiting for lttng-sessiond"); | |
1916 | break; | |
1917 | case EINVAL: | |
1918 | PERROR("sem_timedwait"); | |
1919 | break; | |
1920 | default: | |
1921 | ERR("Unexpected error \"%s\" returned by sem_timedwait", | |
1922 | strerror(errno)); | |
1923 | } | |
cf12a773 MD |
1924 | } |
1925 | break; | |
7b766b16 | 1926 | case -1:/* wait forever */ |
95259bd0 MD |
1927 | do { |
1928 | ret = sem_wait(&constructor_wait); | |
1929 | } while (ret < 0 && errno == EINTR); | |
8aadb54a MD |
1930 | if (ret < 0) { |
1931 | switch (errno) { | |
1932 | case EINVAL: | |
1933 | PERROR("sem_wait"); | |
1934 | break; | |
1935 | default: | |
1936 | ERR("Unexpected error \"%s\" returned by sem_wait", | |
1937 | strerror(errno)); | |
1938 | } | |
1939 | } | |
cf12a773 | 1940 | break; |
7b766b16 | 1941 | case 0: /* no timeout */ |
cf12a773 | 1942 | break; |
11ff9c7d | 1943 | } |
2691221a MD |
1944 | } |
1945 | ||
17dfb34b MD |
1946 | static |
1947 | void lttng_ust_cleanup(int exiting) | |
1948 | { | |
efe0de09 | 1949 | cleanup_sock_info(&global_apps, exiting); |
932cfadb | 1950 | cleanup_sock_info(&local_apps, exiting); |
74f98bc9 | 1951 | local_apps.allowed = 0; |
9d2dfb47 | 1952 | global_apps.allowed = 0; |
efe0de09 MD |
1953 | /* |
1954 | * The teardown in this function all affect data structures | |
1955 | * accessed under the UST lock by the listener thread. This | |
1956 | * lock, along with the lttng_ust_comm_should_quit flag, ensure | |
1957 | * that none of these threads are accessing this data at this | |
1958 | * point. | |
1959 | */ | |
17dfb34b | 1960 | lttng_ust_abi_exit(); |
003fedf4 | 1961 | lttng_ust_events_exit(); |
d58d1454 | 1962 | lttng_perf_counter_exit(); |
34a91bdb | 1963 | lttng_ring_buffer_client_discard_rt_exit(); |
7dd08bec | 1964 | lttng_ring_buffer_client_discard_exit(); |
34a91bdb | 1965 | lttng_ring_buffer_client_overwrite_rt_exit(); |
7dd08bec MD |
1966 | lttng_ring_buffer_client_overwrite_exit(); |
1967 | lttng_ring_buffer_metadata_client_exit(); | |
cf73e0fe | 1968 | lttng_ust_statedump_destroy(); |
17dfb34b MD |
1969 | exit_tracepoint(); |
1970 | if (!exiting) { | |
1971 | /* Reinitialize values for fork */ | |
e85887ff | 1972 | sem_count = sem_count_initial_value; |
17dfb34b MD |
1973 | lttng_ust_comm_should_quit = 0; |
1974 | initialized = 0; | |
1975 | } | |
1976 | } | |
1977 | ||
edaa1431 | 1978 | void __attribute__((destructor)) lttng_ust_exit(void) |
2691221a MD |
1979 | { |
1980 | int ret; | |
1981 | ||
9eb62b9c MD |
1982 | /* |
1983 | * Using pthread_cancel here because: | |
1984 | * A) we don't want to hang application teardown. | |
1985 | * B) the thread is not allocating any resource. | |
1986 | */ | |
1ea11eab MD |
1987 | |
1988 | /* | |
1989 | * Require the communication thread to quit. Synchronize with | |
1990 | * mutexes to ensure it is not in a mutex critical section when | |
1991 | * pthread_cancel is later called. | |
1992 | */ | |
3327ac33 | 1993 | ust_lock_nocheck(); |
1ea11eab | 1994 | lttng_ust_comm_should_quit = 1; |
3327ac33 | 1995 | ust_unlock(); |
1ea11eab | 1996 | |
3327ac33 | 1997 | pthread_mutex_lock(&ust_exit_mutex); |
f5f94532 | 1998 | /* cancel threads */ |
e33f3265 MD |
1999 | if (global_apps.thread_active) { |
2000 | ret = pthread_cancel(global_apps.ust_listener); | |
2001 | if (ret) { | |
2002 | ERR("Error cancelling global ust listener thread: %s", | |
2003 | strerror(ret)); | |
2004 | } else { | |
2005 | global_apps.thread_active = 0; | |
2006 | } | |
2691221a | 2007 | } |
e33f3265 | 2008 | if (local_apps.thread_active) { |
8d20bf54 MD |
2009 | ret = pthread_cancel(local_apps.ust_listener); |
2010 | if (ret) { | |
d94d802c MD |
2011 | ERR("Error cancelling local ust listener thread: %s", |
2012 | strerror(ret)); | |
e33f3265 MD |
2013 | } else { |
2014 | local_apps.thread_active = 0; | |
8d20bf54 | 2015 | } |
8d20bf54 | 2016 | } |
3327ac33 | 2017 | pthread_mutex_unlock(&ust_exit_mutex); |
e33f3265 | 2018 | |
efe0de09 MD |
2019 | /* |
2020 | * Do NOT join threads: use of sys_futex makes it impossible to | |
2021 | * join the threads without using async-cancel, but async-cancel | |
2022 | * is delivered by a signal, which could hit the target thread | |
2023 | * anywhere in its code path, including while the ust_lock() is | |
2024 | * held, causing a deadlock for the other thread. Let the OS | |
2025 | * cleanup the threads if there are stalled in a syscall. | |
2026 | */ | |
17dfb34b | 2027 | lttng_ust_cleanup(1); |
2691221a | 2028 | } |
e822f505 MD |
2029 | |
2030 | /* | |
2031 | * We exclude the worker threads across fork and clone (except | |
2032 | * CLONE_VM), because these system calls only keep the forking thread | |
2033 | * running in the child. Therefore, we don't want to call fork or clone | |
2034 | * in the middle of an tracepoint or ust tracing state modification. | |
2035 | * Holding this mutex protects these structures across fork and clone. | |
2036 | */ | |
b728d87e | 2037 | void ust_before_fork(sigset_t *save_sigset) |
e822f505 MD |
2038 | { |
2039 | /* | |
2040 | * Disable signals. This is to avoid that the child intervenes | |
2041 | * before it is properly setup for tracing. It is safer to | |
2042 | * disable all signals, because then we know we are not breaking | |
2043 | * anything by restoring the original mask. | |
2044 | */ | |
2045 | sigset_t all_sigs; | |
2046 | int ret; | |
2047 | ||
c362addf MD |
2048 | /* Fixup lttng-ust TLS. */ |
2049 | lttng_ust_fixup_tls(); | |
2050 | ||
8c90a710 | 2051 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 2052 | return; |
e822f505 MD |
2053 | /* Disable signals */ |
2054 | sigfillset(&all_sigs); | |
b728d87e | 2055 | ret = sigprocmask(SIG_BLOCK, &all_sigs, save_sigset); |
e822f505 MD |
2056 | if (ret == -1) { |
2057 | PERROR("sigprocmask"); | |
2058 | } | |
458d678c PW |
2059 | |
2060 | pthread_mutex_lock(&ust_fork_mutex); | |
2061 | ||
3327ac33 | 2062 | ust_lock_nocheck(); |
e822f505 MD |
2063 | rcu_bp_before_fork(); |
2064 | } | |
2065 | ||
b728d87e | 2066 | static void ust_after_fork_common(sigset_t *restore_sigset) |
e822f505 MD |
2067 | { |
2068 | int ret; | |
2069 | ||
17dfb34b MD |
2070 | DBG("process %d", getpid()); |
2071 | ust_unlock(); | |
458d678c PW |
2072 | |
2073 | pthread_mutex_unlock(&ust_fork_mutex); | |
2074 | ||
e822f505 | 2075 | /* Restore signals */ |
23c8854a | 2076 | ret = sigprocmask(SIG_SETMASK, restore_sigset, NULL); |
e822f505 MD |
2077 | if (ret == -1) { |
2078 | PERROR("sigprocmask"); | |
2079 | } | |
2080 | } | |
2081 | ||
b728d87e | 2082 | void ust_after_fork_parent(sigset_t *restore_sigset) |
e822f505 | 2083 | { |
8c90a710 | 2084 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 2085 | return; |
17dfb34b | 2086 | DBG("process %d", getpid()); |
e822f505 MD |
2087 | rcu_bp_after_fork_parent(); |
2088 | /* Release mutexes and reenable signals */ | |
b728d87e | 2089 | ust_after_fork_common(restore_sigset); |
e822f505 MD |
2090 | } |
2091 | ||
17dfb34b MD |
2092 | /* |
2093 | * After fork, in the child, we need to cleanup all the leftover state, | |
2094 | * except the worker thread which already magically disappeared thanks | |
2095 | * to the weird Linux fork semantics. After tyding up, we call | |
2096 | * lttng_ust_init() again to start over as a new PID. | |
2097 | * | |
2098 | * This is meant for forks() that have tracing in the child between the | |
2099 | * fork and following exec call (if there is any). | |
2100 | */ | |
b728d87e | 2101 | void ust_after_fork_child(sigset_t *restore_sigset) |
e822f505 | 2102 | { |
8c90a710 | 2103 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 2104 | return; |
06b16a0b | 2105 | lttng_context_vpid_reset(); |
8478887d | 2106 | lttng_context_vtid_reset(); |
3e3a077a | 2107 | lttng_context_procname_reset(); |
17dfb34b | 2108 | DBG("process %d", getpid()); |
e822f505 MD |
2109 | /* Release urcu mutexes */ |
2110 | rcu_bp_after_fork_child(); | |
17dfb34b | 2111 | lttng_ust_cleanup(0); |
e822f505 | 2112 | /* Release mutexes and reenable signals */ |
b728d87e | 2113 | ust_after_fork_common(restore_sigset); |
318dfea9 | 2114 | lttng_ust_init(); |
e822f505 | 2115 | } |
95c25348 | 2116 | |
246be17e | 2117 | void lttng_ust_sockinfo_session_enabled(void *owner) |
95c25348 PW |
2118 | { |
2119 | struct sock_info *sock_info = owner; | |
37dddb65 | 2120 | sock_info->statedump_pending = 1; |
95c25348 | 2121 | } |