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 |
2691221a MD |
23 | #include <sys/types.h> |
24 | #include <sys/socket.h> | |
7fc90dca MD |
25 | #include <sys/mman.h> |
26 | #include <sys/stat.h> | |
58d4b2a2 MD |
27 | #include <sys/types.h> |
28 | #include <sys/wait.h> | |
7fc90dca | 29 | #include <fcntl.h> |
2691221a MD |
30 | #include <unistd.h> |
31 | #include <errno.h> | |
d9e99d10 | 32 | #include <pthread.h> |
11ff9c7d MD |
33 | #include <semaphore.h> |
34 | #include <time.h> | |
1ea11eab | 35 | #include <assert.h> |
e822f505 | 36 | #include <signal.h> |
95c25348 | 37 | #include <dlfcn.h> |
95259bd0 | 38 | #include <urcu/uatomic.h> |
80e2814b | 39 | #include <urcu/futex.h> |
c117fb1b | 40 | #include <urcu/compiler.h> |
1ea11eab | 41 | |
4318ae1b | 42 | #include <lttng/ust-events.h> |
4318ae1b | 43 | #include <lttng/ust-abi.h> |
4318ae1b | 44 | #include <lttng/ust.h> |
7bc53e94 | 45 | #include <lttng/ust-error.h> |
74d81a6c | 46 | #include <lttng/ust-ctl.h> |
8c90a710 | 47 | #include <urcu/tls-compat.h> |
44c72f10 MD |
48 | #include <ust-comm.h> |
49 | #include <usterr-signal-safe.h> | |
cd54f6d9 | 50 | #include <helper.h> |
44c72f10 | 51 | #include "tracepoint-internal.h" |
7dd08bec | 52 | #include "lttng-tracer-core.h" |
08114193 | 53 | #include "compat.h" |
f645cfa7 | 54 | #include "../libringbuffer/tlsfixup.h" |
394598c1 | 55 | #include "lttng-ust-baddr.h" |
edaa1431 MD |
56 | |
57 | /* | |
58 | * Has lttng ust comm constructor been called ? | |
59 | */ | |
60 | static int initialized; | |
61 | ||
1ea11eab | 62 | /* |
17dfb34b MD |
63 | * The ust_lock/ust_unlock lock is used as a communication thread mutex. |
64 | * Held when handling a command, also held by fork() to deal with | |
65 | * removal of threads, and by exit path. | |
3327ac33 MD |
66 | * |
67 | * The UST lock is the centralized mutex across UST tracing control and | |
68 | * probe registration. | |
69 | * | |
70 | * ust_exit_mutex must never nest in ust_mutex. | |
71 | */ | |
72 | static pthread_mutex_t ust_mutex = PTHREAD_MUTEX_INITIALIZER; | |
73 | ||
74 | /* | |
75 | * ust_exit_mutex protects thread_active variable wrt thread exit. It | |
76 | * cannot be done by ust_mutex because pthread_cancel(), which takes an | |
77 | * internal libc lock, cannot nest within ust_mutex. | |
78 | * | |
79 | * It never nests within a ust_mutex. | |
1ea11eab | 80 | */ |
3327ac33 | 81 | static pthread_mutex_t ust_exit_mutex = PTHREAD_MUTEX_INITIALIZER; |
1ea11eab MD |
82 | |
83 | /* Should the ust comm thread quit ? */ | |
84 | static int lttng_ust_comm_should_quit; | |
85 | ||
3327ac33 MD |
86 | /* |
87 | * Return 0 on success, -1 if should quilt. | |
88 | * The lock is taken in both cases. | |
89 | */ | |
90 | int ust_lock(void) | |
91 | { | |
92 | pthread_mutex_lock(&ust_mutex); | |
93 | if (lttng_ust_comm_should_quit) { | |
94 | return -1; | |
95 | } else { | |
96 | return 0; | |
97 | } | |
98 | } | |
99 | ||
100 | /* | |
101 | * ust_lock_nocheck() can be used in constructors/destructors, because | |
102 | * they are already nested within the dynamic loader lock, and therefore | |
103 | * have exclusive access against execution of liblttng-ust destructor. | |
104 | */ | |
105 | void ust_lock_nocheck(void) | |
106 | { | |
107 | pthread_mutex_lock(&ust_mutex); | |
108 | } | |
109 | ||
110 | void ust_unlock(void) | |
111 | { | |
112 | pthread_mutex_unlock(&ust_mutex); | |
113 | } | |
114 | ||
11ff9c7d MD |
115 | /* |
116 | * Wait for either of these before continuing to the main | |
117 | * program: | |
118 | * - the register_done message from sessiond daemon | |
119 | * (will let the sessiond daemon enable sessions before main | |
120 | * starts.) | |
121 | * - sessiond daemon is not reachable. | |
122 | * - timeout (ensuring applications are resilient to session | |
123 | * daemon problems). | |
124 | */ | |
125 | static sem_t constructor_wait; | |
950aab0c MD |
126 | /* |
127 | * Doing this for both the global and local sessiond. | |
128 | */ | |
95259bd0 | 129 | static int sem_count = { 2 }; |
11ff9c7d | 130 | |
e8508a49 MD |
131 | /* |
132 | * Counting nesting within lttng-ust. Used to ensure that calling fork() | |
133 | * from liblttng-ust does not execute the pre/post fork handlers. | |
134 | */ | |
8c90a710 | 135 | static DEFINE_URCU_TLS(int, lttng_ust_nest_count); |
e8508a49 | 136 | |
1ea11eab MD |
137 | /* |
138 | * Info about socket and associated listener thread. | |
139 | */ | |
140 | struct sock_info { | |
11ff9c7d | 141 | const char *name; |
1ea11eab | 142 | pthread_t ust_listener; /* listener thread */ |
46050b1a | 143 | int root_handle; |
8d20bf54 MD |
144 | int constructor_sem_posted; |
145 | int allowed; | |
44e073f5 | 146 | int global; |
e33f3265 | 147 | int thread_active; |
7fc90dca MD |
148 | |
149 | char sock_path[PATH_MAX]; | |
150 | int socket; | |
32ce8569 | 151 | int notify_socket; |
7fc90dca MD |
152 | |
153 | char wait_shm_path[PATH_MAX]; | |
154 | char *wait_shm_mmap; | |
37dddb65 MD |
155 | /* Keep track of lazy state dump not performed yet. */ |
156 | int statedump_pending; | |
1ea11eab | 157 | }; |
2691221a MD |
158 | |
159 | /* Socket from app (connect) to session daemon (listen) for communication */ | |
1ea11eab | 160 | struct sock_info global_apps = { |
11ff9c7d | 161 | .name = "global", |
44e073f5 | 162 | .global = 1, |
7fc90dca | 163 | |
46050b1a | 164 | .root_handle = -1, |
8d20bf54 | 165 | .allowed = 1, |
e33f3265 | 166 | .thread_active = 0, |
7fc90dca | 167 | |
32ce8569 | 168 | .sock_path = LTTNG_DEFAULT_RUNDIR "/" LTTNG_UST_SOCK_FILENAME, |
7fc90dca | 169 | .socket = -1, |
32ce8569 | 170 | .notify_socket = -1, |
7fc90dca | 171 | |
32ce8569 | 172 | .wait_shm_path = "/" LTTNG_UST_WAIT_FILENAME, |
95c25348 | 173 | |
37dddb65 | 174 | .statedump_pending = 0, |
1ea11eab | 175 | }; |
2691221a MD |
176 | |
177 | /* TODO: allow global_apps_sock_path override */ | |
178 | ||
1ea11eab | 179 | struct sock_info local_apps = { |
11ff9c7d | 180 | .name = "local", |
44e073f5 | 181 | .global = 0, |
46050b1a | 182 | .root_handle = -1, |
8d20bf54 | 183 | .allowed = 0, /* Check setuid bit first */ |
e33f3265 | 184 | .thread_active = 0, |
7fc90dca MD |
185 | |
186 | .socket = -1, | |
32ce8569 | 187 | .notify_socket = -1, |
95c25348 | 188 | |
37dddb65 | 189 | .statedump_pending = 0, |
1ea11eab | 190 | }; |
2691221a | 191 | |
37ed587a MD |
192 | static int wait_poll_fallback; |
193 | ||
74d81a6c MD |
194 | static const char *cmd_name_mapping[] = { |
195 | [ LTTNG_UST_RELEASE ] = "Release", | |
196 | [ LTTNG_UST_SESSION ] = "Create Session", | |
197 | [ LTTNG_UST_TRACER_VERSION ] = "Get Tracer Version", | |
198 | ||
199 | [ LTTNG_UST_TRACEPOINT_LIST ] = "Create Tracepoint List", | |
200 | [ LTTNG_UST_WAIT_QUIESCENT ] = "Wait for Quiescent State", | |
201 | [ LTTNG_UST_REGISTER_DONE ] = "Registration Done", | |
202 | [ LTTNG_UST_TRACEPOINT_FIELD_LIST ] = "Create Tracepoint Field List", | |
203 | ||
204 | /* Session FD commands */ | |
205 | [ LTTNG_UST_CHANNEL ] = "Create Channel", | |
206 | [ LTTNG_UST_SESSION_START ] = "Start Session", | |
207 | [ LTTNG_UST_SESSION_STOP ] = "Stop Session", | |
208 | ||
209 | /* Channel FD commands */ | |
210 | [ LTTNG_UST_STREAM ] = "Create Stream", | |
211 | [ LTTNG_UST_EVENT ] = "Create Event", | |
212 | ||
213 | /* Event and Channel FD commands */ | |
214 | [ LTTNG_UST_CONTEXT ] = "Create Context", | |
215 | [ LTTNG_UST_FLUSH_BUFFER ] = "Flush Buffer", | |
216 | ||
217 | /* Event, Channel and Session commands */ | |
218 | [ LTTNG_UST_ENABLE ] = "Enable", | |
219 | [ LTTNG_UST_DISABLE ] = "Disable", | |
220 | ||
221 | /* Tracepoint list commands */ | |
222 | [ LTTNG_UST_TRACEPOINT_LIST_GET ] = "List Next Tracepoint", | |
223 | [ LTTNG_UST_TRACEPOINT_FIELD_LIST_GET ] = "List Next Tracepoint Field", | |
224 | ||
225 | /* Event FD commands */ | |
226 | [ LTTNG_UST_FILTER ] = "Create Filter", | |
75582b3a | 227 | [ LTTNG_UST_EXCLUSION ] = "Add exclusions to event", |
74d81a6c MD |
228 | }; |
229 | ||
ff517991 MD |
230 | static const char *str_timeout; |
231 | static int got_timeout_env; | |
232 | ||
7dd08bec | 233 | extern void lttng_ring_buffer_client_overwrite_init(void); |
34a91bdb | 234 | extern void lttng_ring_buffer_client_overwrite_rt_init(void); |
7dd08bec | 235 | extern void lttng_ring_buffer_client_discard_init(void); |
34a91bdb | 236 | extern void lttng_ring_buffer_client_discard_rt_init(void); |
7dd08bec MD |
237 | extern void lttng_ring_buffer_metadata_client_init(void); |
238 | extern void lttng_ring_buffer_client_overwrite_exit(void); | |
34a91bdb | 239 | extern void lttng_ring_buffer_client_overwrite_rt_exit(void); |
7dd08bec | 240 | extern void lttng_ring_buffer_client_discard_exit(void); |
34a91bdb | 241 | extern void lttng_ring_buffer_client_discard_rt_exit(void); |
7dd08bec | 242 | extern void lttng_ring_buffer_metadata_client_exit(void); |
edaa1431 | 243 | |
3c6f6263 AM |
244 | /* |
245 | * Returns the HOME directory path. Caller MUST NOT free(3) the returned | |
246 | * pointer. | |
247 | */ | |
248 | static | |
249 | const char *get_lttng_home_dir(void) | |
250 | { | |
251 | const char *val; | |
252 | ||
253 | val = (const char *) getenv("LTTNG_HOME"); | |
254 | if (val != NULL) { | |
255 | return val; | |
256 | } | |
257 | return (const char *) getenv("HOME"); | |
258 | } | |
259 | ||
a903623f MD |
260 | /* |
261 | * Force a read (imply TLS fixup for dlopen) of TLS variables. | |
262 | */ | |
263 | static | |
264 | void lttng_fixup_nest_count_tls(void) | |
265 | { | |
8c90a710 | 266 | asm volatile ("" : : "m" (URCU_TLS(lttng_ust_nest_count))); |
a903623f MD |
267 | } |
268 | ||
32ce8569 MD |
269 | int lttng_get_notify_socket(void *owner) |
270 | { | |
271 | struct sock_info *info = owner; | |
272 | ||
273 | return info->notify_socket; | |
274 | } | |
275 | ||
74d81a6c MD |
276 | static |
277 | void print_cmd(int cmd, int handle) | |
278 | { | |
279 | const char *cmd_name = "Unknown"; | |
280 | ||
fd67a004 MD |
281 | if (cmd >= 0 && cmd < LTTNG_ARRAY_SIZE(cmd_name_mapping) |
282 | && cmd_name_mapping[cmd]) { | |
74d81a6c MD |
283 | cmd_name = cmd_name_mapping[cmd]; |
284 | } | |
fd67a004 MD |
285 | DBG("Message Received \"%s\" (%d), Handle \"%s\" (%d)", |
286 | cmd_name, cmd, | |
74d81a6c MD |
287 | lttng_ust_obj_get_name(handle), handle); |
288 | } | |
289 | ||
2691221a | 290 | static |
8d20bf54 | 291 | int setup_local_apps(void) |
2691221a MD |
292 | { |
293 | const char *home_dir; | |
7fc90dca | 294 | uid_t uid; |
2691221a | 295 | |
7fc90dca | 296 | uid = getuid(); |
8d20bf54 MD |
297 | /* |
298 | * Disallow per-user tracing for setuid binaries. | |
299 | */ | |
7fc90dca | 300 | if (uid != geteuid()) { |
9ec6895c | 301 | assert(local_apps.allowed == 0); |
d0a1ae63 | 302 | return 0; |
8d20bf54 | 303 | } |
3c6f6263 | 304 | home_dir = get_lttng_home_dir(); |
9ec6895c MD |
305 | if (!home_dir) { |
306 | WARN("HOME environment variable not set. Disabling LTTng-UST per-user tracing."); | |
307 | assert(local_apps.allowed == 0); | |
2691221a | 308 | return -ENOENT; |
9ec6895c MD |
309 | } |
310 | local_apps.allowed = 1; | |
32ce8569 MD |
311 | snprintf(local_apps.sock_path, PATH_MAX, "%s/%s/%s", |
312 | home_dir, | |
313 | LTTNG_DEFAULT_HOME_RUNDIR, | |
314 | LTTNG_UST_SOCK_FILENAME); | |
315 | snprintf(local_apps.wait_shm_path, PATH_MAX, "/%s-%u", | |
316 | LTTNG_UST_WAIT_FILENAME, | |
317 | uid); | |
2691221a MD |
318 | return 0; |
319 | } | |
320 | ||
ff517991 MD |
321 | /* |
322 | * Get notify_sock timeout, in ms. | |
323 | * -1: don't wait. 0: wait forever. >0: timeout, in ms. | |
324 | */ | |
325 | static | |
326 | long get_timeout(void) | |
327 | { | |
328 | long constructor_delay_ms = LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS; | |
329 | ||
330 | if (!got_timeout_env) { | |
331 | str_timeout = getenv("LTTNG_UST_REGISTER_TIMEOUT"); | |
332 | got_timeout_env = 1; | |
333 | } | |
334 | if (str_timeout) | |
335 | constructor_delay_ms = strtol(str_timeout, NULL, 10); | |
336 | return constructor_delay_ms; | |
337 | } | |
338 | ||
339 | static | |
340 | long get_notify_sock_timeout(void) | |
341 | { | |
342 | return get_timeout(); | |
343 | } | |
344 | ||
345 | /* | |
346 | * Return values: -1: don't wait. 0: wait forever. 1: timeout wait. | |
347 | */ | |
348 | static | |
349 | int get_constructor_timeout(struct timespec *constructor_timeout) | |
350 | { | |
351 | long constructor_delay_ms; | |
352 | int ret; | |
353 | ||
354 | constructor_delay_ms = get_timeout(); | |
355 | ||
356 | switch (constructor_delay_ms) { | |
357 | case -1:/* fall-through */ | |
358 | case 0: | |
359 | return constructor_delay_ms; | |
360 | default: | |
361 | break; | |
362 | } | |
363 | ||
364 | /* | |
365 | * If we are unable to find the current time, don't wait. | |
366 | */ | |
367 | ret = clock_gettime(CLOCK_REALTIME, constructor_timeout); | |
368 | if (ret) { | |
369 | return -1; | |
370 | } | |
371 | constructor_timeout->tv_sec += constructor_delay_ms / 1000UL; | |
372 | constructor_timeout->tv_nsec += | |
373 | (constructor_delay_ms % 1000UL) * 1000000UL; | |
374 | if (constructor_timeout->tv_nsec >= 1000000000UL) { | |
375 | constructor_timeout->tv_sec++; | |
376 | constructor_timeout->tv_nsec -= 1000000000UL; | |
377 | } | |
378 | return 1; | |
379 | } | |
380 | ||
2691221a | 381 | static |
32ce8569 | 382 | int register_to_sessiond(int socket, enum ustctl_socket_type type) |
2691221a | 383 | { |
32ce8569 MD |
384 | return ustcomm_send_reg_msg(socket, |
385 | type, | |
386 | CAA_BITS_PER_LONG, | |
387 | lttng_alignof(uint8_t) * CHAR_BIT, | |
388 | lttng_alignof(uint16_t) * CHAR_BIT, | |
389 | lttng_alignof(uint32_t) * CHAR_BIT, | |
390 | lttng_alignof(uint64_t) * CHAR_BIT, | |
391 | lttng_alignof(unsigned long) * CHAR_BIT); | |
2691221a MD |
392 | } |
393 | ||
d9e99d10 | 394 | static |
57773204 | 395 | int send_reply(int sock, struct ustcomm_ust_reply *lur) |
d9e99d10 | 396 | { |
9eb62b9c | 397 | ssize_t len; |
d3a492d1 | 398 | |
57773204 | 399 | len = ustcomm_send_unix_sock(sock, lur, sizeof(*lur)); |
d3a492d1 | 400 | switch (len) { |
a4be8962 | 401 | case sizeof(*lur): |
d3a492d1 MD |
402 | DBG("message successfully sent"); |
403 | return 0; | |
7bc53e94 MD |
404 | default: |
405 | if (len == -ECONNRESET) { | |
406 | DBG("remote end closed connection"); | |
d3a492d1 MD |
407 | return 0; |
408 | } | |
7bc53e94 MD |
409 | if (len < 0) |
410 | return len; | |
411 | DBG("incorrect message size: %zd", len); | |
412 | return -EINVAL; | |
d3a492d1 MD |
413 | } |
414 | } | |
415 | ||
416 | static | |
edaa1431 | 417 | int handle_register_done(struct sock_info *sock_info) |
11ff9c7d MD |
418 | { |
419 | int ret; | |
420 | ||
edaa1431 MD |
421 | if (sock_info->constructor_sem_posted) |
422 | return 0; | |
423 | sock_info->constructor_sem_posted = 1; | |
56cd7e2f MD |
424 | if (uatomic_read(&sem_count) <= 0) { |
425 | return 0; | |
426 | } | |
95259bd0 MD |
427 | ret = uatomic_add_return(&sem_count, -1); |
428 | if (ret == 0) { | |
429 | ret = sem_post(&constructor_wait); | |
430 | assert(!ret); | |
431 | } | |
11ff9c7d MD |
432 | return 0; |
433 | } | |
434 | ||
37dddb65 MD |
435 | /* |
436 | * Only execute pending statedump after the constructor semaphore has | |
437 | * been posted by each listener thread. This means statedump will only | |
438 | * be performed after the "registration done" command is received from | |
439 | * each session daemon the application is connected to. | |
440 | * | |
441 | * This ensures we don't run into deadlock issues with the dynamic | |
442 | * loader mutex, which is held while the constructor is called and | |
443 | * waiting on the constructor semaphore. All operations requiring this | |
444 | * dynamic loader lock need to be postponed using this mechanism. | |
445 | */ | |
446 | static | |
447 | void handle_pending_statedump(struct sock_info *sock_info) | |
448 | { | |
449 | int ctor_passed = sock_info->constructor_sem_posted; | |
450 | ||
451 | if (ctor_passed && sock_info->statedump_pending) { | |
452 | sock_info->statedump_pending = 0; | |
453 | lttng_handle_pending_statedump(sock_info); | |
454 | } | |
455 | } | |
456 | ||
11ff9c7d MD |
457 | static |
458 | int handle_message(struct sock_info *sock_info, | |
57773204 | 459 | int sock, struct ustcomm_ust_msg *lum) |
d3a492d1 | 460 | { |
1ea11eab | 461 | int ret = 0; |
b61ce3b2 | 462 | const struct lttng_ust_objd_ops *ops; |
57773204 | 463 | struct ustcomm_ust_reply lur; |
ef9ff354 | 464 | union ust_args args; |
40003310 | 465 | ssize_t len; |
1ea11eab | 466 | |
46050b1a MD |
467 | memset(&lur, 0, sizeof(lur)); |
468 | ||
3327ac33 | 469 | if (ust_lock()) { |
74d81a6c | 470 | ret = -LTTNG_UST_ERR_EXITING; |
1ea11eab MD |
471 | goto end; |
472 | } | |
9eb62b9c | 473 | |
46050b1a MD |
474 | ops = objd_ops(lum->handle); |
475 | if (!ops) { | |
476 | ret = -ENOENT; | |
477 | goto end; | |
1ea11eab | 478 | } |
46050b1a MD |
479 | |
480 | switch (lum->cmd) { | |
11ff9c7d MD |
481 | case LTTNG_UST_REGISTER_DONE: |
482 | if (lum->handle == LTTNG_UST_ROOT_HANDLE) | |
edaa1431 | 483 | ret = handle_register_done(sock_info); |
11ff9c7d MD |
484 | else |
485 | ret = -EINVAL; | |
486 | break; | |
46050b1a MD |
487 | case LTTNG_UST_RELEASE: |
488 | if (lum->handle == LTTNG_UST_ROOT_HANDLE) | |
489 | ret = -EPERM; | |
490 | else | |
1849ef7c | 491 | ret = lttng_ust_objd_unref(lum->handle, 1); |
d9e99d10 | 492 | break; |
2d78951a MD |
493 | case LTTNG_UST_FILTER: |
494 | { | |
495 | /* Receive filter data */ | |
f488575f | 496 | struct lttng_ust_filter_bytecode_node *bytecode; |
2d78951a | 497 | |
cd54f6d9 | 498 | if (lum->u.filter.data_size > FILTER_BYTECODE_MAX_LEN) { |
7bc53e94 | 499 | ERR("Filter data size is too large: %u bytes", |
2d78951a MD |
500 | lum->u.filter.data_size); |
501 | ret = -EINVAL; | |
502 | goto error; | |
503 | } | |
2734ca65 | 504 | |
885b1dfd | 505 | if (lum->u.filter.reloc_offset > lum->u.filter.data_size) { |
7bc53e94 | 506 | ERR("Filter reloc offset %u is not within data", |
2734ca65 CB |
507 | lum->u.filter.reloc_offset); |
508 | ret = -EINVAL; | |
509 | goto error; | |
510 | } | |
511 | ||
cd54f6d9 MD |
512 | bytecode = zmalloc(sizeof(*bytecode) + lum->u.filter.data_size); |
513 | if (!bytecode) { | |
514 | ret = -ENOMEM; | |
515 | goto error; | |
516 | } | |
f488575f | 517 | len = ustcomm_recv_unix_sock(sock, bytecode->bc.data, |
2d78951a MD |
518 | lum->u.filter.data_size); |
519 | switch (len) { | |
520 | case 0: /* orderly shutdown */ | |
521 | ret = 0; | |
cd54f6d9 | 522 | free(bytecode); |
2d78951a | 523 | goto error; |
2d78951a MD |
524 | default: |
525 | if (len == lum->u.filter.data_size) { | |
7bc53e94 | 526 | DBG("filter data received"); |
2d78951a | 527 | break; |
7bc53e94 MD |
528 | } else if (len < 0) { |
529 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
530 | if (len == -ECONNRESET) { | |
531 | ERR("%s remote end closed connection", sock_info->name); | |
532 | ret = len; | |
533 | free(bytecode); | |
534 | goto error; | |
535 | } | |
536 | ret = len; | |
eb8bf361 | 537 | free(bytecode); |
7bc53e94 | 538 | goto end; |
2d78951a | 539 | } else { |
7bc53e94 | 540 | DBG("incorrect filter data message size: %zd", len); |
2d78951a | 541 | ret = -EINVAL; |
cd54f6d9 | 542 | free(bytecode); |
2d78951a MD |
543 | goto end; |
544 | } | |
545 | } | |
f488575f MD |
546 | bytecode->bc.len = lum->u.filter.data_size; |
547 | bytecode->bc.reloc_offset = lum->u.filter.reloc_offset; | |
3f6fd224 | 548 | bytecode->bc.seqnum = lum->u.filter.seqnum; |
cd54f6d9 | 549 | if (ops->cmd) { |
2d78951a | 550 | ret = ops->cmd(lum->handle, lum->cmd, |
cd54f6d9 | 551 | (unsigned long) bytecode, |
f59ed768 | 552 | &args, sock_info); |
cd54f6d9 MD |
553 | if (ret) { |
554 | free(bytecode); | |
555 | } | |
556 | /* don't free bytecode if everything went fine. */ | |
557 | } else { | |
2d78951a | 558 | ret = -ENOSYS; |
cd54f6d9 MD |
559 | free(bytecode); |
560 | } | |
2d78951a MD |
561 | break; |
562 | } | |
86e36163 JI |
563 | case LTTNG_UST_EXCLUSION: |
564 | { | |
565 | /* Receive exclusion names */ | |
566 | struct lttng_ust_excluder_node *node; | |
567 | unsigned int count; | |
568 | ||
569 | count = lum->u.exclusion.count; | |
570 | if (count == 0) { | |
571 | /* There are no names to read */ | |
572 | ret = 0; | |
573 | goto error; | |
574 | } | |
575 | node = zmalloc(sizeof(*node) + | |
576 | count * LTTNG_UST_SYM_NAME_LEN); | |
577 | if (!node) { | |
578 | ret = -ENOMEM; | |
579 | goto error; | |
580 | } | |
581 | node->excluder.count = count; | |
582 | len = ustcomm_recv_unix_sock(sock, node->excluder.names, | |
583 | count * LTTNG_UST_SYM_NAME_LEN); | |
584 | switch (len) { | |
585 | case 0: /* orderly shutdown */ | |
586 | ret = 0; | |
587 | free(node); | |
588 | goto error; | |
589 | default: | |
590 | if (len == count * LTTNG_UST_SYM_NAME_LEN) { | |
591 | DBG("Exclusion data received"); | |
592 | break; | |
593 | } else if (len < 0) { | |
594 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
595 | if (len == -ECONNRESET) { | |
596 | ERR("%s remote end closed connection", sock_info->name); | |
597 | ret = len; | |
598 | free(node); | |
599 | goto error; | |
600 | } | |
601 | ret = len; | |
602 | free(node); | |
603 | goto end; | |
604 | } else { | |
605 | DBG("Incorrect exclusion data message size: %zd", len); | |
606 | ret = -EINVAL; | |
607 | free(node); | |
608 | goto end; | |
609 | } | |
610 | } | |
611 | if (ops->cmd) { | |
612 | ret = ops->cmd(lum->handle, lum->cmd, | |
613 | (unsigned long) node, | |
614 | &args, sock_info); | |
615 | if (ret) { | |
616 | free(node); | |
617 | } | |
618 | /* Don't free exclusion data if everything went fine. */ | |
619 | } else { | |
620 | ret = -ENOSYS; | |
621 | free(node); | |
622 | } | |
623 | break; | |
624 | } | |
74d81a6c MD |
625 | case LTTNG_UST_CHANNEL: |
626 | { | |
627 | void *chan_data; | |
ff0f5728 | 628 | int wakeup_fd; |
74d81a6c MD |
629 | |
630 | len = ustcomm_recv_channel_from_sessiond(sock, | |
ff0f5728 MD |
631 | &chan_data, lum->u.channel.len, |
632 | &wakeup_fd); | |
74d81a6c MD |
633 | switch (len) { |
634 | case 0: /* orderly shutdown */ | |
635 | ret = 0; | |
636 | goto error; | |
637 | default: | |
638 | if (len == lum->u.channel.len) { | |
639 | DBG("channel data received"); | |
640 | break; | |
641 | } else if (len < 0) { | |
642 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
643 | if (len == -ECONNRESET) { | |
644 | ERR("%s remote end closed connection", sock_info->name); | |
645 | ret = len; | |
646 | goto error; | |
647 | } | |
648 | ret = len; | |
649 | goto end; | |
650 | } else { | |
651 | DBG("incorrect channel data message size: %zd", len); | |
652 | ret = -EINVAL; | |
653 | goto end; | |
654 | } | |
655 | } | |
656 | args.channel.chan_data = chan_data; | |
ff0f5728 | 657 | args.channel.wakeup_fd = wakeup_fd; |
74d81a6c MD |
658 | if (ops->cmd) |
659 | ret = ops->cmd(lum->handle, lum->cmd, | |
660 | (unsigned long) &lum->u, | |
661 | &args, sock_info); | |
662 | else | |
663 | ret = -ENOSYS; | |
664 | break; | |
665 | } | |
666 | case LTTNG_UST_STREAM: | |
667 | { | |
668 | /* Receive shm_fd, wakeup_fd */ | |
669 | ret = ustcomm_recv_stream_from_sessiond(sock, | |
670 | &lum->u.stream.len, | |
671 | &args.stream.shm_fd, | |
672 | &args.stream.wakeup_fd); | |
673 | if (ret) { | |
674 | goto end; | |
675 | } | |
676 | if (ops->cmd) | |
677 | ret = ops->cmd(lum->handle, lum->cmd, | |
678 | (unsigned long) &lum->u, | |
679 | &args, sock_info); | |
680 | else | |
681 | ret = -ENOSYS; | |
682 | break; | |
683 | } | |
d9e99d10 | 684 | default: |
46050b1a MD |
685 | if (ops->cmd) |
686 | ret = ops->cmd(lum->handle, lum->cmd, | |
ef9ff354 | 687 | (unsigned long) &lum->u, |
f59ed768 | 688 | &args, sock_info); |
46050b1a MD |
689 | else |
690 | ret = -ENOSYS; | |
691 | break; | |
d9e99d10 | 692 | } |
46050b1a | 693 | |
1ea11eab | 694 | end: |
46050b1a MD |
695 | lur.handle = lum->handle; |
696 | lur.cmd = lum->cmd; | |
697 | lur.ret_val = ret; | |
698 | if (ret >= 0) { | |
7bc53e94 | 699 | lur.ret_code = LTTNG_UST_OK; |
46050b1a | 700 | } else { |
7bc53e94 MD |
701 | /* |
702 | * Use -LTTNG_UST_ERR as wildcard for UST internal | |
703 | * error that are not caused by the transport, except if | |
704 | * we already have a more precise error message to | |
705 | * report. | |
706 | */ | |
64b2564e DG |
707 | if (ret > -LTTNG_UST_ERR) { |
708 | /* Translate code to UST error. */ | |
709 | switch (ret) { | |
710 | case -EEXIST: | |
711 | lur.ret_code = -LTTNG_UST_ERR_EXIST; | |
712 | break; | |
713 | case -EINVAL: | |
714 | lur.ret_code = -LTTNG_UST_ERR_INVAL; | |
715 | break; | |
716 | case -ENOENT: | |
717 | lur.ret_code = -LTTNG_UST_ERR_NOENT; | |
718 | break; | |
719 | case -EPERM: | |
720 | lur.ret_code = -LTTNG_UST_ERR_PERM; | |
721 | break; | |
722 | case -ENOSYS: | |
723 | lur.ret_code = -LTTNG_UST_ERR_NOSYS; | |
724 | break; | |
725 | default: | |
726 | lur.ret_code = -LTTNG_UST_ERR; | |
727 | break; | |
728 | } | |
729 | } else { | |
7bc53e94 | 730 | lur.ret_code = ret; |
64b2564e | 731 | } |
46050b1a | 732 | } |
e6ea14c5 MD |
733 | if (ret >= 0) { |
734 | switch (lum->cmd) { | |
e6ea14c5 MD |
735 | case LTTNG_UST_TRACER_VERSION: |
736 | lur.u.version = lum->u.version; | |
737 | break; | |
738 | case LTTNG_UST_TRACEPOINT_LIST_GET: | |
739 | memcpy(&lur.u.tracepoint, &lum->u.tracepoint, sizeof(lur.u.tracepoint)); | |
740 | break; | |
741 | } | |
381c0f1e | 742 | } |
74d81a6c | 743 | DBG("Return value: %d", lur.ret_val); |
46050b1a | 744 | ret = send_reply(sock, &lur); |
193183fb | 745 | if (ret < 0) { |
7bc53e94 | 746 | DBG("error sending reply"); |
193183fb MD |
747 | goto error; |
748 | } | |
46050b1a | 749 | |
40003310 MD |
750 | /* |
751 | * LTTNG_UST_TRACEPOINT_FIELD_LIST_GET needs to send the field | |
752 | * after the reply. | |
753 | */ | |
7bc53e94 | 754 | if (lur.ret_code == LTTNG_UST_OK) { |
40003310 MD |
755 | switch (lum->cmd) { |
756 | case LTTNG_UST_TRACEPOINT_FIELD_LIST_GET: | |
757 | len = ustcomm_send_unix_sock(sock, | |
758 | &args.field_list.entry, | |
759 | sizeof(args.field_list.entry)); | |
7bc53e94 MD |
760 | if (len < 0) { |
761 | ret = len; | |
762 | goto error; | |
763 | } | |
40003310 | 764 | if (len != sizeof(args.field_list.entry)) { |
7bc53e94 | 765 | ret = -EINVAL; |
40003310 MD |
766 | goto error; |
767 | } | |
768 | } | |
769 | } | |
ef9ff354 | 770 | |
381c0f1e | 771 | error: |
17dfb34b | 772 | ust_unlock(); |
d9e99d10 | 773 | |
37dddb65 MD |
774 | /* |
775 | * Performed delayed statedump operations outside of the UST | |
776 | * lock. We need to take the dynamic loader lock before we take | |
777 | * the UST lock internally within handle_pending_statedump(). | |
778 | */ | |
779 | handle_pending_statedump(sock_info); | |
246be17e | 780 | |
37dddb65 | 781 | return ret; |
246be17e PW |
782 | } |
783 | ||
46050b1a | 784 | static |
efe0de09 | 785 | void cleanup_sock_info(struct sock_info *sock_info, int exiting) |
46050b1a MD |
786 | { |
787 | int ret; | |
788 | ||
5b14aab3 MD |
789 | if (sock_info->root_handle != -1) { |
790 | ret = lttng_ust_objd_unref(sock_info->root_handle, 1); | |
791 | if (ret) { | |
792 | ERR("Error unref root handle"); | |
793 | } | |
794 | sock_info->root_handle = -1; | |
795 | } | |
796 | sock_info->constructor_sem_posted = 0; | |
797 | ||
798 | /* | |
799 | * wait_shm_mmap, socket and notify socket are used by listener | |
800 | * threads outside of the ust lock, so we cannot tear them down | |
801 | * ourselves, because we cannot join on these threads. Leave | |
802 | * responsibility of cleaning up these resources to the OS | |
803 | * process exit. | |
804 | */ | |
805 | if (exiting) | |
806 | return; | |
807 | ||
46050b1a | 808 | if (sock_info->socket != -1) { |
e6973a89 | 809 | ret = ustcomm_close_unix_sock(sock_info->socket); |
46050b1a | 810 | if (ret) { |
32ce8569 | 811 | ERR("Error closing ust cmd socket"); |
46050b1a MD |
812 | } |
813 | sock_info->socket = -1; | |
814 | } | |
32ce8569 MD |
815 | if (sock_info->notify_socket != -1) { |
816 | ret = ustcomm_close_unix_sock(sock_info->notify_socket); | |
817 | if (ret) { | |
818 | ERR("Error closing ust notify socket"); | |
819 | } | |
820 | sock_info->notify_socket = -1; | |
821 | } | |
5b14aab3 | 822 | if (sock_info->wait_shm_mmap) { |
7fc90dca MD |
823 | ret = munmap(sock_info->wait_shm_mmap, sysconf(_SC_PAGE_SIZE)); |
824 | if (ret) { | |
825 | ERR("Error unmapping wait shm"); | |
826 | } | |
827 | sock_info->wait_shm_mmap = NULL; | |
828 | } | |
829 | } | |
830 | ||
58d4b2a2 | 831 | /* |
33bbeb90 MD |
832 | * Using fork to set umask in the child process (not multi-thread safe). |
833 | * We deal with the shm_open vs ftruncate race (happening when the | |
834 | * sessiond owns the shm and does not let everybody modify it, to ensure | |
835 | * safety against shm_unlink) by simply letting the mmap fail and | |
836 | * retrying after a few seconds. | |
837 | * For global shm, everybody has rw access to it until the sessiond | |
838 | * starts. | |
58d4b2a2 | 839 | */ |
7fc90dca | 840 | static |
58d4b2a2 | 841 | int get_wait_shm(struct sock_info *sock_info, size_t mmap_size) |
7fc90dca | 842 | { |
7fc90dca | 843 | int wait_shm_fd, ret; |
58d4b2a2 | 844 | pid_t pid; |
44e073f5 | 845 | |
58d4b2a2 | 846 | /* |
33bbeb90 | 847 | * Try to open read-only. |
58d4b2a2 | 848 | */ |
33bbeb90 | 849 | wait_shm_fd = shm_open(sock_info->wait_shm_path, O_RDONLY, 0); |
58d4b2a2 | 850 | if (wait_shm_fd >= 0) { |
7aa76730 MD |
851 | int32_t tmp_read; |
852 | ssize_t len; | |
853 | size_t bytes_read = 0; | |
854 | ||
855 | /* | |
856 | * Try to read the fd. If unable to do so, try opening | |
857 | * it in write mode. | |
858 | */ | |
859 | do { | |
860 | len = read(wait_shm_fd, | |
861 | &((char *) &tmp_read)[bytes_read], | |
862 | sizeof(tmp_read) - bytes_read); | |
863 | if (len > 0) { | |
864 | bytes_read += len; | |
865 | } | |
866 | } while ((len < 0 && errno == EINTR) | |
867 | || (len > 0 && bytes_read < sizeof(tmp_read))); | |
868 | if (bytes_read != sizeof(tmp_read)) { | |
869 | ret = close(wait_shm_fd); | |
870 | if (ret) { | |
871 | ERR("close wait_shm_fd"); | |
872 | } | |
873 | goto open_write; | |
874 | } | |
58d4b2a2 MD |
875 | goto end; |
876 | } else if (wait_shm_fd < 0 && errno != ENOENT) { | |
877 | /* | |
33bbeb90 MD |
878 | * Real-only open did not work, and it's not because the |
879 | * entry was not present. It's a failure that prohibits | |
880 | * using shm. | |
58d4b2a2 | 881 | */ |
7fc90dca | 882 | ERR("Error opening shm %s", sock_info->wait_shm_path); |
58d4b2a2 | 883 | goto end; |
7fc90dca | 884 | } |
7aa76730 MD |
885 | |
886 | open_write: | |
7fc90dca | 887 | /* |
7aa76730 MD |
888 | * If the open failed because the file did not exist, or because |
889 | * the file was not truncated yet, try creating it ourself. | |
7fc90dca | 890 | */ |
8c90a710 | 891 | URCU_TLS(lttng_ust_nest_count)++; |
58d4b2a2 | 892 | pid = fork(); |
8c90a710 | 893 | URCU_TLS(lttng_ust_nest_count)--; |
58d4b2a2 MD |
894 | if (pid > 0) { |
895 | int status; | |
896 | ||
897 | /* | |
898 | * Parent: wait for child to return, in which case the | |
899 | * shared memory map will have been created. | |
900 | */ | |
901 | pid = wait(&status); | |
b7d3cb32 | 902 | if (pid < 0 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) { |
58d4b2a2 MD |
903 | wait_shm_fd = -1; |
904 | goto end; | |
7fc90dca | 905 | } |
58d4b2a2 MD |
906 | /* |
907 | * Try to open read-only again after creation. | |
908 | */ | |
33bbeb90 | 909 | wait_shm_fd = shm_open(sock_info->wait_shm_path, O_RDONLY, 0); |
58d4b2a2 MD |
910 | if (wait_shm_fd < 0) { |
911 | /* | |
912 | * Real-only open did not work. It's a failure | |
913 | * that prohibits using shm. | |
914 | */ | |
915 | ERR("Error opening shm %s", sock_info->wait_shm_path); | |
916 | goto end; | |
917 | } | |
918 | goto end; | |
919 | } else if (pid == 0) { | |
920 | int create_mode; | |
921 | ||
922 | /* Child */ | |
33bbeb90 | 923 | create_mode = S_IRUSR | S_IWUSR | S_IRGRP; |
58d4b2a2 | 924 | if (sock_info->global) |
33bbeb90 | 925 | create_mode |= S_IROTH | S_IWGRP | S_IWOTH; |
58d4b2a2 MD |
926 | /* |
927 | * We're alone in a child process, so we can modify the | |
928 | * process-wide umask. | |
929 | */ | |
33bbeb90 | 930 | umask(~create_mode); |
58d4b2a2 | 931 | /* |
33bbeb90 MD |
932 | * Try creating shm (or get rw access). |
933 | * We don't do an exclusive open, because we allow other | |
934 | * processes to create+ftruncate it concurrently. | |
58d4b2a2 MD |
935 | */ |
936 | wait_shm_fd = shm_open(sock_info->wait_shm_path, | |
937 | O_RDWR | O_CREAT, create_mode); | |
938 | if (wait_shm_fd >= 0) { | |
939 | ret = ftruncate(wait_shm_fd, mmap_size); | |
940 | if (ret) { | |
941 | PERROR("ftruncate"); | |
b0c1425d | 942 | _exit(EXIT_FAILURE); |
58d4b2a2 | 943 | } |
b0c1425d | 944 | _exit(EXIT_SUCCESS); |
58d4b2a2 | 945 | } |
33bbeb90 MD |
946 | /* |
947 | * For local shm, we need to have rw access to accept | |
948 | * opening it: this means the local sessiond will be | |
949 | * able to wake us up. For global shm, we open it even | |
950 | * if rw access is not granted, because the root.root | |
951 | * sessiond will be able to override all rights and wake | |
952 | * us up. | |
953 | */ | |
954 | if (!sock_info->global && errno != EACCES) { | |
58d4b2a2 | 955 | ERR("Error opening shm %s", sock_info->wait_shm_path); |
5d3bc5ed | 956 | _exit(EXIT_FAILURE); |
58d4b2a2 MD |
957 | } |
958 | /* | |
33bbeb90 MD |
959 | * The shm exists, but we cannot open it RW. Report |
960 | * success. | |
58d4b2a2 | 961 | */ |
5d3bc5ed | 962 | _exit(EXIT_SUCCESS); |
58d4b2a2 MD |
963 | } else { |
964 | return -1; | |
7fc90dca | 965 | } |
58d4b2a2 | 966 | end: |
33bbeb90 MD |
967 | if (wait_shm_fd >= 0 && !sock_info->global) { |
968 | struct stat statbuf; | |
969 | ||
970 | /* | |
971 | * Ensure that our user is the owner of the shm file for | |
972 | * local shm. If we do not own the file, it means our | |
973 | * sessiond will not have access to wake us up (there is | |
974 | * probably a rogue process trying to fake our | |
975 | * sessiond). Fallback to polling method in this case. | |
976 | */ | |
977 | ret = fstat(wait_shm_fd, &statbuf); | |
978 | if (ret) { | |
979 | PERROR("fstat"); | |
980 | goto error_close; | |
981 | } | |
982 | if (statbuf.st_uid != getuid()) | |
983 | goto error_close; | |
984 | } | |
58d4b2a2 | 985 | return wait_shm_fd; |
33bbeb90 MD |
986 | |
987 | error_close: | |
988 | ret = close(wait_shm_fd); | |
989 | if (ret) { | |
990 | PERROR("Error closing fd"); | |
991 | } | |
992 | return -1; | |
58d4b2a2 MD |
993 | } |
994 | ||
995 | static | |
996 | char *get_map_shm(struct sock_info *sock_info) | |
997 | { | |
998 | size_t mmap_size = sysconf(_SC_PAGE_SIZE); | |
999 | int wait_shm_fd, ret; | |
1000 | char *wait_shm_mmap; | |
1001 | ||
1002 | wait_shm_fd = get_wait_shm(sock_info, mmap_size); | |
1003 | if (wait_shm_fd < 0) { | |
1004 | goto error; | |
44e073f5 | 1005 | } |
7fc90dca MD |
1006 | wait_shm_mmap = mmap(NULL, mmap_size, PROT_READ, |
1007 | MAP_SHARED, wait_shm_fd, 0); | |
7fc90dca MD |
1008 | /* close shm fd immediately after taking the mmap reference */ |
1009 | ret = close(wait_shm_fd); | |
1010 | if (ret) { | |
33bbeb90 MD |
1011 | PERROR("Error closing fd"); |
1012 | } | |
1013 | if (wait_shm_mmap == MAP_FAILED) { | |
1014 | DBG("mmap error (can be caused by race with sessiond). Fallback to poll mode."); | |
1015 | goto error; | |
7fc90dca MD |
1016 | } |
1017 | return wait_shm_mmap; | |
1018 | ||
1019 | error: | |
1020 | return NULL; | |
1021 | } | |
1022 | ||
1023 | static | |
1024 | void wait_for_sessiond(struct sock_info *sock_info) | |
1025 | { | |
efe0de09 | 1026 | int ret; |
80e2814b | 1027 | |
3327ac33 | 1028 | if (ust_lock()) { |
7fc90dca MD |
1029 | goto quit; |
1030 | } | |
37ed587a MD |
1031 | if (wait_poll_fallback) { |
1032 | goto error; | |
1033 | } | |
7fc90dca MD |
1034 | if (!sock_info->wait_shm_mmap) { |
1035 | sock_info->wait_shm_mmap = get_map_shm(sock_info); | |
1036 | if (!sock_info->wait_shm_mmap) | |
1037 | goto error; | |
1038 | } | |
1039 | ust_unlock(); | |
1040 | ||
1041 | DBG("Waiting for %s apps sessiond", sock_info->name); | |
80e2814b MD |
1042 | /* Wait for futex wakeup */ |
1043 | if (uatomic_read((int32_t *) sock_info->wait_shm_mmap) == 0) { | |
1044 | ret = futex_async((int32_t *) sock_info->wait_shm_mmap, | |
1045 | FUTEX_WAIT, 0, NULL, NULL, 0); | |
80e2814b | 1046 | if (ret < 0) { |
37ed587a MD |
1047 | if (errno == EFAULT) { |
1048 | wait_poll_fallback = 1; | |
a8b870ad | 1049 | DBG( |
37ed587a MD |
1050 | "Linux kernels 2.6.33 to 3.0 (with the exception of stable versions) " |
1051 | "do not support FUTEX_WAKE on read-only memory mappings correctly. " | |
1052 | "Please upgrade your kernel " | |
1053 | "(fix is commit 9ea71503a8ed9184d2d0b8ccc4d269d05f7940ae in Linux kernel " | |
1054 | "mainline). LTTng-UST will use polling mode fallback."); | |
cd27263b MD |
1055 | if (ust_debug()) |
1056 | PERROR("futex"); | |
37ed587a | 1057 | } |
80e2814b MD |
1058 | } |
1059 | } | |
7fc90dca MD |
1060 | return; |
1061 | ||
1062 | quit: | |
1063 | ust_unlock(); | |
1064 | return; | |
1065 | ||
1066 | error: | |
1067 | ust_unlock(); | |
7fc90dca | 1068 | return; |
46050b1a MD |
1069 | } |
1070 | ||
1ea11eab MD |
1071 | /* |
1072 | * This thread does not allocate any resource, except within | |
1073 | * handle_message, within mutex protection. This mutex protects against | |
1074 | * fork and exit. | |
98bf993f | 1075 | * The other moment it allocates resources is at socket connection, which |
1ea11eab MD |
1076 | * is also protected by the mutex. |
1077 | */ | |
d9e99d10 MD |
1078 | static |
1079 | void *ust_listener_thread(void *arg) | |
1080 | { | |
1ea11eab | 1081 | struct sock_info *sock_info = arg; |
c0eedf81 | 1082 | int sock, ret, prev_connect_failed = 0, has_waited = 0; |
ff517991 | 1083 | long timeout; |
d9e99d10 | 1084 | |
9eb62b9c MD |
1085 | /* Restart trying to connect to the session daemon */ |
1086 | restart: | |
c0eedf81 MD |
1087 | if (prev_connect_failed) { |
1088 | /* Wait for sessiond availability with pipe */ | |
1089 | wait_for_sessiond(sock_info); | |
1090 | if (has_waited) { | |
1091 | has_waited = 0; | |
1092 | /* | |
1093 | * Sleep for 5 seconds before retrying after a | |
1094 | * sequence of failure / wait / failure. This | |
1095 | * deals with a killed or broken session daemon. | |
1096 | */ | |
1097 | sleep(5); | |
1098 | } | |
1099 | has_waited = 1; | |
1100 | prev_connect_failed = 0; | |
1101 | } | |
9eb62b9c | 1102 | |
1ea11eab | 1103 | if (sock_info->socket != -1) { |
e6973a89 | 1104 | ret = ustcomm_close_unix_sock(sock_info->socket); |
1ea11eab | 1105 | if (ret) { |
32ce8569 MD |
1106 | ERR("Error closing %s ust cmd socket", |
1107 | sock_info->name); | |
1ea11eab MD |
1108 | } |
1109 | sock_info->socket = -1; | |
1110 | } | |
32ce8569 MD |
1111 | if (sock_info->notify_socket != -1) { |
1112 | ret = ustcomm_close_unix_sock(sock_info->notify_socket); | |
1113 | if (ret) { | |
1114 | ERR("Error closing %s ust notify socket", | |
1115 | sock_info->name); | |
1116 | } | |
1117 | sock_info->notify_socket = -1; | |
1118 | } | |
46050b1a | 1119 | |
321f2351 MD |
1120 | /* |
1121 | * Register. We need to perform both connect and sending | |
1122 | * registration message before doing the next connect otherwise | |
1123 | * we may reach unix socket connect queue max limits and block | |
1124 | * on the 2nd connect while the session daemon is awaiting the | |
1125 | * first connect registration message. | |
1126 | */ | |
1127 | /* Connect cmd socket */ | |
1128 | ret = ustcomm_connect_unix_sock(sock_info->sock_path); | |
1129 | if (ret < 0) { | |
1130 | DBG("Info: sessiond not accepting connections to %s apps socket", sock_info->name); | |
1131 | prev_connect_failed = 1; | |
5b14aab3 | 1132 | |
3327ac33 | 1133 | if (ust_lock()) { |
321f2351 | 1134 | goto quit; |
32ce8569 | 1135 | } |
46050b1a | 1136 | |
e3426ddc | 1137 | /* |
321f2351 MD |
1138 | * If we cannot find the sessiond daemon, don't delay |
1139 | * constructor execution. | |
e3426ddc | 1140 | */ |
321f2351 MD |
1141 | ret = handle_register_done(sock_info); |
1142 | assert(!ret); | |
1143 | ust_unlock(); | |
1144 | goto restart; | |
27fe9f21 | 1145 | } |
321f2351 | 1146 | sock_info->socket = ret; |
27fe9f21 | 1147 | |
3327ac33 | 1148 | if (ust_lock()) { |
5b14aab3 MD |
1149 | goto quit; |
1150 | } | |
1151 | ||
46050b1a MD |
1152 | /* |
1153 | * Create only one root handle per listener thread for the whole | |
f59ed768 MD |
1154 | * process lifetime, so we ensure we get ID which is statically |
1155 | * assigned to the root handle. | |
46050b1a MD |
1156 | */ |
1157 | if (sock_info->root_handle == -1) { | |
1158 | ret = lttng_abi_create_root_handle(); | |
a51070bb | 1159 | if (ret < 0) { |
46050b1a | 1160 | ERR("Error creating root handle"); |
46050b1a MD |
1161 | goto quit; |
1162 | } | |
1163 | sock_info->root_handle = ret; | |
9eb62b9c | 1164 | } |
1ea11eab | 1165 | |
32ce8569 | 1166 | ret = register_to_sessiond(sock_info->socket, USTCTL_SOCKET_CMD); |
9eb62b9c | 1167 | if (ret < 0) { |
32ce8569 MD |
1168 | ERR("Error registering to %s ust cmd socket", |
1169 | sock_info->name); | |
c0eedf81 | 1170 | prev_connect_failed = 1; |
11ff9c7d MD |
1171 | /* |
1172 | * If we cannot register to the sessiond daemon, don't | |
1173 | * delay constructor execution. | |
1174 | */ | |
edaa1431 | 1175 | ret = handle_register_done(sock_info); |
11ff9c7d | 1176 | assert(!ret); |
17dfb34b | 1177 | ust_unlock(); |
9eb62b9c MD |
1178 | goto restart; |
1179 | } | |
321f2351 MD |
1180 | |
1181 | ust_unlock(); | |
1182 | ||
1183 | /* Connect notify socket */ | |
1184 | ret = ustcomm_connect_unix_sock(sock_info->sock_path); | |
1185 | if (ret < 0) { | |
1186 | DBG("Info: sessiond not accepting connections to %s apps socket", sock_info->name); | |
1187 | prev_connect_failed = 1; | |
1188 | ||
3327ac33 | 1189 | if (ust_lock()) { |
321f2351 MD |
1190 | goto quit; |
1191 | } | |
1192 | ||
1193 | /* | |
1194 | * If we cannot find the sessiond daemon, don't delay | |
1195 | * constructor execution. | |
1196 | */ | |
1197 | ret = handle_register_done(sock_info); | |
1198 | assert(!ret); | |
1199 | ust_unlock(); | |
1200 | goto restart; | |
1201 | } | |
1202 | sock_info->notify_socket = ret; | |
1203 | ||
1204 | timeout = get_notify_sock_timeout(); | |
1205 | if (timeout >= 0) { | |
1206 | /* | |
1207 | * Give at least 10ms to sessiond to reply to | |
1208 | * notifications. | |
1209 | */ | |
1210 | if (timeout < 10) | |
1211 | timeout = 10; | |
1212 | ret = ustcomm_setsockopt_rcv_timeout(sock_info->notify_socket, | |
1213 | timeout); | |
1214 | if (ret < 0) { | |
1215 | WARN("Error setting socket receive timeout"); | |
1216 | } | |
1217 | ret = ustcomm_setsockopt_snd_timeout(sock_info->notify_socket, | |
1218 | timeout); | |
1219 | if (ret < 0) { | |
1220 | WARN("Error setting socket send timeout"); | |
1221 | } | |
1222 | } else if (timeout < -1) { | |
1223 | WARN("Unsupported timeout value %ld", timeout); | |
1224 | } | |
1225 | ||
3327ac33 | 1226 | if (ust_lock()) { |
321f2351 MD |
1227 | goto quit; |
1228 | } | |
1229 | ||
32ce8569 MD |
1230 | ret = register_to_sessiond(sock_info->notify_socket, |
1231 | USTCTL_SOCKET_NOTIFY); | |
1232 | if (ret < 0) { | |
1233 | ERR("Error registering to %s ust notify socket", | |
1234 | sock_info->name); | |
1235 | prev_connect_failed = 1; | |
1236 | /* | |
1237 | * If we cannot register to the sessiond daemon, don't | |
1238 | * delay constructor execution. | |
1239 | */ | |
1240 | ret = handle_register_done(sock_info); | |
1241 | assert(!ret); | |
1242 | ust_unlock(); | |
1243 | goto restart; | |
1244 | } | |
1245 | sock = sock_info->socket; | |
1246 | ||
17dfb34b | 1247 | ust_unlock(); |
46050b1a | 1248 | |
d9e99d10 MD |
1249 | for (;;) { |
1250 | ssize_t len; | |
57773204 | 1251 | struct ustcomm_ust_msg lum; |
d9e99d10 | 1252 | |
57773204 | 1253 | len = ustcomm_recv_unix_sock(sock, &lum, sizeof(lum)); |
d9e99d10 MD |
1254 | switch (len) { |
1255 | case 0: /* orderly shutdown */ | |
7dd08bec | 1256 | DBG("%s lttng-sessiond has performed an orderly shutdown", sock_info->name); |
3327ac33 | 1257 | if (ust_lock()) { |
d5e1fea6 MD |
1258 | goto quit; |
1259 | } | |
8236ba10 MD |
1260 | /* |
1261 | * Either sessiond has shutdown or refused us by closing the socket. | |
1262 | * In either case, we don't want to delay construction execution, | |
1263 | * and we need to wait before retry. | |
1264 | */ | |
1265 | prev_connect_failed = 1; | |
1266 | /* | |
1267 | * If we cannot register to the sessiond daemon, don't | |
1268 | * delay constructor execution. | |
1269 | */ | |
1270 | ret = handle_register_done(sock_info); | |
1271 | assert(!ret); | |
1272 | ust_unlock(); | |
d9e99d10 | 1273 | goto end; |
e7723462 | 1274 | case sizeof(lum): |
74d81a6c | 1275 | print_cmd(lum.cmd, lum.handle); |
11ff9c7d | 1276 | ret = handle_message(sock_info, sock, &lum); |
7bc53e94 | 1277 | if (ret) { |
11ff9c7d | 1278 | ERR("Error handling message for %s socket", sock_info->name); |
d9e99d10 MD |
1279 | } |
1280 | continue; | |
7bc53e94 MD |
1281 | default: |
1282 | if (len < 0) { | |
1283 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
1284 | } else { | |
1285 | DBG("incorrect message size (%s socket): %zd", sock_info->name, len); | |
1286 | } | |
1287 | if (len == -ECONNRESET) { | |
1288 | DBG("%s remote end closed connection", sock_info->name); | |
d9e99d10 MD |
1289 | goto end; |
1290 | } | |
1291 | goto end; | |
d9e99d10 MD |
1292 | } |
1293 | ||
1294 | } | |
1295 | end: | |
3327ac33 | 1296 | if (ust_lock()) { |
d5e1fea6 MD |
1297 | goto quit; |
1298 | } | |
f59ed768 MD |
1299 | /* Cleanup socket handles before trying to reconnect */ |
1300 | lttng_ust_objd_table_owner_cleanup(sock_info); | |
1301 | ust_unlock(); | |
9eb62b9c | 1302 | goto restart; /* try to reconnect */ |
e33f3265 | 1303 | |
1ea11eab | 1304 | quit: |
e33f3265 | 1305 | ust_unlock(); |
3327ac33 MD |
1306 | |
1307 | pthread_mutex_lock(&ust_exit_mutex); | |
1308 | sock_info->thread_active = 0; | |
1309 | pthread_mutex_unlock(&ust_exit_mutex); | |
d9e99d10 MD |
1310 | return NULL; |
1311 | } | |
1312 | ||
2691221a MD |
1313 | /* |
1314 | * sessiond monitoring thread: monitor presence of global and per-user | |
1315 | * sessiond by polling the application common named pipe. | |
1316 | */ | |
edaa1431 | 1317 | void __attribute__((constructor)) lttng_ust_init(void) |
2691221a | 1318 | { |
11ff9c7d | 1319 | struct timespec constructor_timeout; |
ae6a58bf | 1320 | sigset_t sig_all_blocked, orig_parent_mask; |
1879f67f | 1321 | pthread_attr_t thread_attr; |
cf12a773 | 1322 | int timeout_mode; |
2691221a MD |
1323 | int ret; |
1324 | ||
edaa1431 MD |
1325 | if (uatomic_xchg(&initialized, 1) == 1) |
1326 | return; | |
1327 | ||
eddd8d5d MD |
1328 | /* |
1329 | * Fixup interdependency between TLS fixup mutex (which happens | |
1330 | * to be the dynamic linker mutex) and ust_lock, taken within | |
1331 | * the ust lock. | |
1332 | */ | |
f645cfa7 | 1333 | lttng_fixup_ringbuffer_tls(); |
4158a15a | 1334 | lttng_fixup_vtid_tls(); |
a903623f | 1335 | lttng_fixup_nest_count_tls(); |
009745db | 1336 | lttng_fixup_procname_tls(); |
eddd8d5d | 1337 | |
edaa1431 MD |
1338 | /* |
1339 | * We want precise control over the order in which we construct | |
1340 | * our sub-libraries vs starting to receive commands from | |
1341 | * sessiond (otherwise leading to errors when trying to create | |
1342 | * sessiond before the init functions are completed). | |
1343 | */ | |
2691221a | 1344 | init_usterr(); |
edaa1431 | 1345 | init_tracepoint(); |
7dd08bec MD |
1346 | lttng_ring_buffer_metadata_client_init(); |
1347 | lttng_ring_buffer_client_overwrite_init(); | |
34a91bdb | 1348 | lttng_ring_buffer_client_overwrite_rt_init(); |
7dd08bec | 1349 | lttng_ring_buffer_client_discard_init(); |
34a91bdb | 1350 | lttng_ring_buffer_client_discard_rt_init(); |
a0a3bef9 | 1351 | lttng_context_init(); |
2691221a | 1352 | |
ff517991 | 1353 | timeout_mode = get_constructor_timeout(&constructor_timeout); |
11ff9c7d | 1354 | |
95259bd0 | 1355 | ret = sem_init(&constructor_wait, 0, 0); |
11ff9c7d MD |
1356 | assert(!ret); |
1357 | ||
8d20bf54 | 1358 | ret = setup_local_apps(); |
2691221a | 1359 | if (ret) { |
9ec6895c | 1360 | DBG("local apps setup returned %d", ret); |
2691221a | 1361 | } |
ae6a58bf WP |
1362 | |
1363 | /* A new thread created by pthread_create inherits the signal mask | |
1364 | * from the parent. To avoid any signal being received by the | |
1365 | * listener thread, we block all signals temporarily in the parent, | |
1366 | * while we create the listener thread. | |
1367 | */ | |
1368 | sigfillset(&sig_all_blocked); | |
1369 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_parent_mask); | |
1370 | if (ret) { | |
d94d802c | 1371 | ERR("pthread_sigmask: %s", strerror(ret)); |
ae6a58bf WP |
1372 | } |
1373 | ||
1879f67f MG |
1374 | ret = pthread_attr_init(&thread_attr); |
1375 | if (ret) { | |
1376 | ERR("pthread_attr_init: %s", strerror(ret)); | |
1377 | } | |
1378 | ret = pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED); | |
1379 | if (ret) { | |
1380 | ERR("pthread_attr_setdetachstate: %s", strerror(ret)); | |
1381 | } | |
1382 | ||
c0bbbd5a | 1383 | pthread_mutex_lock(&ust_exit_mutex); |
1879f67f | 1384 | ret = pthread_create(&global_apps.ust_listener, &thread_attr, |
dde70ea0 | 1385 | ust_listener_thread, &global_apps); |
d94d802c MD |
1386 | if (ret) { |
1387 | ERR("pthread_create global: %s", strerror(ret)); | |
1388 | } | |
e33f3265 | 1389 | global_apps.thread_active = 1; |
c0bbbd5a | 1390 | pthread_mutex_unlock(&ust_exit_mutex); |
e33f3265 | 1391 | |
8d20bf54 | 1392 | if (local_apps.allowed) { |
c0bbbd5a | 1393 | pthread_mutex_lock(&ust_exit_mutex); |
1879f67f | 1394 | ret = pthread_create(&local_apps.ust_listener, &thread_attr, |
dde70ea0 | 1395 | ust_listener_thread, &local_apps); |
d94d802c MD |
1396 | if (ret) { |
1397 | ERR("pthread_create local: %s", strerror(ret)); | |
1398 | } | |
e33f3265 | 1399 | local_apps.thread_active = 1; |
c0bbbd5a | 1400 | pthread_mutex_unlock(&ust_exit_mutex); |
8d20bf54 MD |
1401 | } else { |
1402 | handle_register_done(&local_apps); | |
1403 | } | |
1879f67f MG |
1404 | ret = pthread_attr_destroy(&thread_attr); |
1405 | if (ret) { | |
1406 | ERR("pthread_attr_destroy: %s", strerror(ret)); | |
1407 | } | |
8d20bf54 | 1408 | |
ae6a58bf WP |
1409 | /* Restore original signal mask in parent */ |
1410 | ret = pthread_sigmask(SIG_SETMASK, &orig_parent_mask, NULL); | |
1411 | if (ret) { | |
d94d802c | 1412 | ERR("pthread_sigmask: %s", strerror(ret)); |
ae6a58bf WP |
1413 | } |
1414 | ||
cf12a773 MD |
1415 | switch (timeout_mode) { |
1416 | case 1: /* timeout wait */ | |
95259bd0 MD |
1417 | do { |
1418 | ret = sem_timedwait(&constructor_wait, | |
1419 | &constructor_timeout); | |
1420 | } while (ret < 0 && errno == EINTR); | |
cf12a773 | 1421 | if (ret < 0 && errno == ETIMEDOUT) { |
7dd08bec | 1422 | ERR("Timed out waiting for lttng-sessiond"); |
cf12a773 MD |
1423 | } else { |
1424 | assert(!ret); | |
1425 | } | |
1426 | break; | |
7b766b16 | 1427 | case -1:/* wait forever */ |
95259bd0 MD |
1428 | do { |
1429 | ret = sem_wait(&constructor_wait); | |
1430 | } while (ret < 0 && errno == EINTR); | |
11ff9c7d | 1431 | assert(!ret); |
cf12a773 | 1432 | break; |
7b766b16 | 1433 | case 0: /* no timeout */ |
cf12a773 | 1434 | break; |
11ff9c7d | 1435 | } |
2691221a MD |
1436 | } |
1437 | ||
17dfb34b MD |
1438 | static |
1439 | void lttng_ust_cleanup(int exiting) | |
1440 | { | |
efe0de09 | 1441 | cleanup_sock_info(&global_apps, exiting); |
17dfb34b | 1442 | if (local_apps.allowed) { |
efe0de09 | 1443 | cleanup_sock_info(&local_apps, exiting); |
17dfb34b | 1444 | } |
efe0de09 MD |
1445 | /* |
1446 | * The teardown in this function all affect data structures | |
1447 | * accessed under the UST lock by the listener thread. This | |
1448 | * lock, along with the lttng_ust_comm_should_quit flag, ensure | |
1449 | * that none of these threads are accessing this data at this | |
1450 | * point. | |
1451 | */ | |
17dfb34b | 1452 | lttng_ust_abi_exit(); |
003fedf4 | 1453 | lttng_ust_events_exit(); |
a0a3bef9 | 1454 | lttng_context_exit(); |
34a91bdb | 1455 | lttng_ring_buffer_client_discard_rt_exit(); |
7dd08bec | 1456 | lttng_ring_buffer_client_discard_exit(); |
34a91bdb | 1457 | lttng_ring_buffer_client_overwrite_rt_exit(); |
7dd08bec MD |
1458 | lttng_ring_buffer_client_overwrite_exit(); |
1459 | lttng_ring_buffer_metadata_client_exit(); | |
17dfb34b MD |
1460 | exit_tracepoint(); |
1461 | if (!exiting) { | |
1462 | /* Reinitialize values for fork */ | |
1463 | sem_count = 2; | |
1464 | lttng_ust_comm_should_quit = 0; | |
1465 | initialized = 0; | |
1466 | } | |
1467 | } | |
1468 | ||
edaa1431 | 1469 | void __attribute__((destructor)) lttng_ust_exit(void) |
2691221a MD |
1470 | { |
1471 | int ret; | |
1472 | ||
9eb62b9c MD |
1473 | /* |
1474 | * Using pthread_cancel here because: | |
1475 | * A) we don't want to hang application teardown. | |
1476 | * B) the thread is not allocating any resource. | |
1477 | */ | |
1ea11eab MD |
1478 | |
1479 | /* | |
1480 | * Require the communication thread to quit. Synchronize with | |
1481 | * mutexes to ensure it is not in a mutex critical section when | |
1482 | * pthread_cancel is later called. | |
1483 | */ | |
3327ac33 | 1484 | ust_lock_nocheck(); |
1ea11eab | 1485 | lttng_ust_comm_should_quit = 1; |
3327ac33 | 1486 | ust_unlock(); |
1ea11eab | 1487 | |
3327ac33 | 1488 | pthread_mutex_lock(&ust_exit_mutex); |
f5f94532 | 1489 | /* cancel threads */ |
e33f3265 MD |
1490 | if (global_apps.thread_active) { |
1491 | ret = pthread_cancel(global_apps.ust_listener); | |
1492 | if (ret) { | |
1493 | ERR("Error cancelling global ust listener thread: %s", | |
1494 | strerror(ret)); | |
1495 | } else { | |
1496 | global_apps.thread_active = 0; | |
1497 | } | |
2691221a | 1498 | } |
e33f3265 | 1499 | if (local_apps.thread_active) { |
8d20bf54 MD |
1500 | ret = pthread_cancel(local_apps.ust_listener); |
1501 | if (ret) { | |
d94d802c MD |
1502 | ERR("Error cancelling local ust listener thread: %s", |
1503 | strerror(ret)); | |
e33f3265 MD |
1504 | } else { |
1505 | local_apps.thread_active = 0; | |
8d20bf54 | 1506 | } |
8d20bf54 | 1507 | } |
3327ac33 | 1508 | pthread_mutex_unlock(&ust_exit_mutex); |
e33f3265 | 1509 | |
efe0de09 MD |
1510 | /* |
1511 | * Do NOT join threads: use of sys_futex makes it impossible to | |
1512 | * join the threads without using async-cancel, but async-cancel | |
1513 | * is delivered by a signal, which could hit the target thread | |
1514 | * anywhere in its code path, including while the ust_lock() is | |
1515 | * held, causing a deadlock for the other thread. Let the OS | |
1516 | * cleanup the threads if there are stalled in a syscall. | |
1517 | */ | |
17dfb34b | 1518 | lttng_ust_cleanup(1); |
2691221a | 1519 | } |
e822f505 MD |
1520 | |
1521 | /* | |
1522 | * We exclude the worker threads across fork and clone (except | |
1523 | * CLONE_VM), because these system calls only keep the forking thread | |
1524 | * running in the child. Therefore, we don't want to call fork or clone | |
1525 | * in the middle of an tracepoint or ust tracing state modification. | |
1526 | * Holding this mutex protects these structures across fork and clone. | |
1527 | */ | |
b728d87e | 1528 | void ust_before_fork(sigset_t *save_sigset) |
e822f505 MD |
1529 | { |
1530 | /* | |
1531 | * Disable signals. This is to avoid that the child intervenes | |
1532 | * before it is properly setup for tracing. It is safer to | |
1533 | * disable all signals, because then we know we are not breaking | |
1534 | * anything by restoring the original mask. | |
1535 | */ | |
1536 | sigset_t all_sigs; | |
1537 | int ret; | |
1538 | ||
8c90a710 | 1539 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 1540 | return; |
e822f505 MD |
1541 | /* Disable signals */ |
1542 | sigfillset(&all_sigs); | |
b728d87e | 1543 | ret = sigprocmask(SIG_BLOCK, &all_sigs, save_sigset); |
e822f505 MD |
1544 | if (ret == -1) { |
1545 | PERROR("sigprocmask"); | |
1546 | } | |
3327ac33 | 1547 | ust_lock_nocheck(); |
e822f505 MD |
1548 | rcu_bp_before_fork(); |
1549 | } | |
1550 | ||
b728d87e | 1551 | static void ust_after_fork_common(sigset_t *restore_sigset) |
e822f505 MD |
1552 | { |
1553 | int ret; | |
1554 | ||
17dfb34b MD |
1555 | DBG("process %d", getpid()); |
1556 | ust_unlock(); | |
e822f505 | 1557 | /* Restore signals */ |
23c8854a | 1558 | ret = sigprocmask(SIG_SETMASK, restore_sigset, NULL); |
e822f505 MD |
1559 | if (ret == -1) { |
1560 | PERROR("sigprocmask"); | |
1561 | } | |
1562 | } | |
1563 | ||
b728d87e | 1564 | void ust_after_fork_parent(sigset_t *restore_sigset) |
e822f505 | 1565 | { |
8c90a710 | 1566 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 1567 | return; |
17dfb34b | 1568 | DBG("process %d", getpid()); |
e822f505 MD |
1569 | rcu_bp_after_fork_parent(); |
1570 | /* Release mutexes and reenable signals */ | |
b728d87e | 1571 | ust_after_fork_common(restore_sigset); |
e822f505 MD |
1572 | } |
1573 | ||
17dfb34b MD |
1574 | /* |
1575 | * After fork, in the child, we need to cleanup all the leftover state, | |
1576 | * except the worker thread which already magically disappeared thanks | |
1577 | * to the weird Linux fork semantics. After tyding up, we call | |
1578 | * lttng_ust_init() again to start over as a new PID. | |
1579 | * | |
1580 | * This is meant for forks() that have tracing in the child between the | |
1581 | * fork and following exec call (if there is any). | |
1582 | */ | |
b728d87e | 1583 | void ust_after_fork_child(sigset_t *restore_sigset) |
e822f505 | 1584 | { |
8c90a710 | 1585 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 1586 | return; |
17dfb34b | 1587 | DBG("process %d", getpid()); |
e822f505 MD |
1588 | /* Release urcu mutexes */ |
1589 | rcu_bp_after_fork_child(); | |
17dfb34b | 1590 | lttng_ust_cleanup(0); |
a93bfc45 | 1591 | lttng_context_vtid_reset(); |
e822f505 | 1592 | /* Release mutexes and reenable signals */ |
b728d87e | 1593 | ust_after_fork_common(restore_sigset); |
318dfea9 | 1594 | lttng_ust_init(); |
e822f505 | 1595 | } |
95c25348 | 1596 | |
246be17e | 1597 | void lttng_ust_sockinfo_session_enabled(void *owner) |
95c25348 PW |
1598 | { |
1599 | struct sock_info *sock_info = owner; | |
37dddb65 | 1600 | sock_info->statedump_pending = 1; |
95c25348 | 1601 | } |