Commit | Line | Data |
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2691221a | 1 | /* |
c0c0989a | 2 | * SPDX-License-Identifier: LGPL-2.1-only |
2691221a MD |
3 | * |
4 | * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca> | |
5 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
2691221a MD |
6 | */ |
7 | ||
80e2814b | 8 | #define _LGPL_SOURCE |
b4051ad8 | 9 | #include <stddef.h> |
fb31eb73 | 10 | #include <stdint.h> |
2691221a MD |
11 | #include <sys/types.h> |
12 | #include <sys/socket.h> | |
7fc90dca MD |
13 | #include <sys/mman.h> |
14 | #include <sys/stat.h> | |
58d4b2a2 MD |
15 | #include <sys/types.h> |
16 | #include <sys/wait.h> | |
b2292d85 | 17 | #include <dlfcn.h> |
7fc90dca | 18 | #include <fcntl.h> |
2691221a MD |
19 | #include <unistd.h> |
20 | #include <errno.h> | |
d9e99d10 | 21 | #include <pthread.h> |
11ff9c7d MD |
22 | #include <semaphore.h> |
23 | #include <time.h> | |
1ea11eab | 24 | #include <assert.h> |
e822f505 | 25 | #include <signal.h> |
6f97f9c2 | 26 | #include <limits.h> |
95259bd0 | 27 | #include <urcu/uatomic.h> |
c117fb1b | 28 | #include <urcu/compiler.h> |
10544ee8 | 29 | #include <lttng/urcu/urcu-ust.h> |
1ea11eab | 30 | |
eae3c729 | 31 | #include <lttng/ust-utils.h> |
4318ae1b | 32 | #include <lttng/ust-events.h> |
4318ae1b | 33 | #include <lttng/ust-abi.h> |
d0c8f180 | 34 | #include <lttng/ust-fork.h> |
7bc53e94 | 35 | #include <lttng/ust-error.h> |
74d81a6c | 36 | #include <lttng/ust-ctl.h> |
d1f1110f | 37 | #include <lttng/ust-libc-wrapper.h> |
4b4a1337 | 38 | #include <lttng/ust-thread.h> |
3d3dc207 | 39 | #include <lttng/ust-tracer.h> |
fca97dfd | 40 | #include <lttng/ust-common.h> |
8c90a710 | 41 | #include <urcu/tls-compat.h> |
08ba2503 | 42 | #include "lib/lttng-ust/futex.h" |
9d315d6d MJ |
43 | #include "common/ustcomm.h" |
44 | #include "common/ust-fd.h" | |
45 | #include "common/logging.h" | |
46 | #include "common/macros.h" | |
8f51c684 | 47 | #include "common/tracepoint.h" |
7dd08bec | 48 | #include "lttng-tracer-core.h" |
27b98e6c MJ |
49 | #include "common/compat/pthread.h" |
50 | #include "common/procname.h" | |
e4db8f98 | 51 | #include "common/ringbuffer/rb-init.h" |
cf73e0fe | 52 | #include "lttng-ust-statedump.h" |
f41a6b5f | 53 | #include "common/clock.h" |
910dcd72 | 54 | #include "common/getenv.h" |
36c52fff | 55 | #include "lib/lttng-ust/events.h" |
5287fad0 | 56 | #include "context-internal.h" |
9d315d6d | 57 | #include "common/align.h" |
8cd08025 MJ |
58 | #include "common/counter-clients/clients.h" |
59 | #include "common/ringbuffer-clients/clients.h" | |
edaa1431 MD |
60 | |
61 | /* | |
62 | * Has lttng ust comm constructor been called ? | |
63 | */ | |
64 | static int initialized; | |
65 | ||
1ea11eab | 66 | /* |
17dfb34b MD |
67 | * The ust_lock/ust_unlock lock is used as a communication thread mutex. |
68 | * Held when handling a command, also held by fork() to deal with | |
69 | * removal of threads, and by exit path. | |
3327ac33 MD |
70 | * |
71 | * The UST lock is the centralized mutex across UST tracing control and | |
72 | * probe registration. | |
73 | * | |
74 | * ust_exit_mutex must never nest in ust_mutex. | |
d58d1454 | 75 | * |
4770bd47 MD |
76 | * ust_fork_mutex must never nest in ust_mutex. |
77 | * | |
d58d1454 MD |
78 | * ust_mutex_nest is a per-thread nesting counter, allowing the perf |
79 | * counter lazy initialization called by events within the statedump, | |
80 | * which traces while the ust_mutex is held. | |
4770bd47 MD |
81 | * |
82 | * ust_lock nests within the dynamic loader lock (within glibc) because | |
83 | * it is taken within the library constructor. | |
c1be081a MD |
84 | * |
85 | * The ust fd tracker lock nests within the ust_mutex. | |
3327ac33 MD |
86 | */ |
87 | static pthread_mutex_t ust_mutex = PTHREAD_MUTEX_INITIALIZER; | |
88 | ||
d58d1454 | 89 | /* Allow nesting the ust_mutex within the same thread. */ |
16adecf1 | 90 | static DEFINE_URCU_TLS(int, ust_mutex_nest); |
d58d1454 | 91 | |
3327ac33 MD |
92 | /* |
93 | * ust_exit_mutex protects thread_active variable wrt thread exit. It | |
94 | * cannot be done by ust_mutex because pthread_cancel(), which takes an | |
95 | * internal libc lock, cannot nest within ust_mutex. | |
96 | * | |
97 | * It never nests within a ust_mutex. | |
1ea11eab | 98 | */ |
3327ac33 | 99 | static pthread_mutex_t ust_exit_mutex = PTHREAD_MUTEX_INITIALIZER; |
1ea11eab | 100 | |
458d678c PW |
101 | /* |
102 | * ust_fork_mutex protects base address statedump tracing against forks. It | |
103 | * prevents the dynamic loader lock to be taken (by base address statedump | |
104 | * tracing) while a fork is happening, thus preventing deadlock issues with | |
105 | * the dynamic loader lock. | |
106 | */ | |
107 | static pthread_mutex_t ust_fork_mutex = PTHREAD_MUTEX_INITIALIZER; | |
108 | ||
1ea11eab MD |
109 | /* Should the ust comm thread quit ? */ |
110 | static int lttng_ust_comm_should_quit; | |
111 | ||
07b57e5e MD |
112 | /* |
113 | * This variable can be tested by applications to check whether | |
114 | * lttng-ust is loaded. They simply have to define their own | |
115 | * "lttng_ust_loaded" weak symbol, and test it. It is set to 1 by the | |
116 | * library constructor. | |
117 | */ | |
118 | int lttng_ust_loaded __attribute__((weak)); | |
119 | ||
3327ac33 | 120 | /* |
d58d1454 | 121 | * Return 0 on success, -1 if should quit. |
3327ac33 | 122 | * The lock is taken in both cases. |
d58d1454 | 123 | * Signal-safe. |
3327ac33 MD |
124 | */ |
125 | int ust_lock(void) | |
126 | { | |
d58d1454 | 127 | sigset_t sig_all_blocked, orig_mask; |
e446ad80 | 128 | int ret, oldstate; |
d58d1454 | 129 | |
e446ad80 MD |
130 | ret = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldstate); |
131 | if (ret) { | |
132 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
133 | } | |
134 | if (oldstate != PTHREAD_CANCEL_ENABLE) { | |
135 | ERR("pthread_setcancelstate: unexpected oldstate"); | |
136 | } | |
d58d1454 MD |
137 | sigfillset(&sig_all_blocked); |
138 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
139 | if (ret) { | |
140 | ERR("pthread_sigmask: %s", strerror(ret)); | |
141 | } | |
142 | if (!URCU_TLS(ust_mutex_nest)++) | |
143 | pthread_mutex_lock(&ust_mutex); | |
144 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
145 | if (ret) { | |
146 | ERR("pthread_sigmask: %s", strerror(ret)); | |
147 | } | |
3327ac33 MD |
148 | if (lttng_ust_comm_should_quit) { |
149 | return -1; | |
150 | } else { | |
151 | return 0; | |
152 | } | |
153 | } | |
154 | ||
155 | /* | |
156 | * ust_lock_nocheck() can be used in constructors/destructors, because | |
157 | * they are already nested within the dynamic loader lock, and therefore | |
158 | * have exclusive access against execution of liblttng-ust destructor. | |
d58d1454 | 159 | * Signal-safe. |
3327ac33 MD |
160 | */ |
161 | void ust_lock_nocheck(void) | |
162 | { | |
d58d1454 | 163 | sigset_t sig_all_blocked, orig_mask; |
e446ad80 | 164 | int ret, oldstate; |
d58d1454 | 165 | |
e446ad80 MD |
166 | ret = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldstate); |
167 | if (ret) { | |
168 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
169 | } | |
170 | if (oldstate != PTHREAD_CANCEL_ENABLE) { | |
171 | ERR("pthread_setcancelstate: unexpected oldstate"); | |
172 | } | |
d58d1454 MD |
173 | sigfillset(&sig_all_blocked); |
174 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
175 | if (ret) { | |
176 | ERR("pthread_sigmask: %s", strerror(ret)); | |
177 | } | |
178 | if (!URCU_TLS(ust_mutex_nest)++) | |
179 | pthread_mutex_lock(&ust_mutex); | |
180 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
181 | if (ret) { | |
182 | ERR("pthread_sigmask: %s", strerror(ret)); | |
183 | } | |
3327ac33 MD |
184 | } |
185 | ||
d58d1454 MD |
186 | /* |
187 | * Signal-safe. | |
188 | */ | |
3327ac33 MD |
189 | void ust_unlock(void) |
190 | { | |
d58d1454 | 191 | sigset_t sig_all_blocked, orig_mask; |
e446ad80 | 192 | int ret, oldstate; |
d58d1454 MD |
193 | |
194 | sigfillset(&sig_all_blocked); | |
195 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
196 | if (ret) { | |
197 | ERR("pthread_sigmask: %s", strerror(ret)); | |
198 | } | |
199 | if (!--URCU_TLS(ust_mutex_nest)) | |
200 | pthread_mutex_unlock(&ust_mutex); | |
201 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
202 | if (ret) { | |
203 | ERR("pthread_sigmask: %s", strerror(ret)); | |
204 | } | |
e446ad80 MD |
205 | ret = pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldstate); |
206 | if (ret) { | |
207 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
208 | } | |
209 | if (oldstate != PTHREAD_CANCEL_DISABLE) { | |
210 | ERR("pthread_setcancelstate: unexpected oldstate"); | |
211 | } | |
3327ac33 MD |
212 | } |
213 | ||
11ff9c7d MD |
214 | /* |
215 | * Wait for either of these before continuing to the main | |
216 | * program: | |
217 | * - the register_done message from sessiond daemon | |
218 | * (will let the sessiond daemon enable sessions before main | |
219 | * starts.) | |
220 | * - sessiond daemon is not reachable. | |
221 | * - timeout (ensuring applications are resilient to session | |
222 | * daemon problems). | |
223 | */ | |
224 | static sem_t constructor_wait; | |
950aab0c MD |
225 | /* |
226 | * Doing this for both the global and local sessiond. | |
227 | */ | |
eb0e6022 GAPG |
228 | enum { |
229 | sem_count_initial_value = 4, | |
230 | }; | |
231 | ||
232 | static int sem_count = sem_count_initial_value; | |
11ff9c7d | 233 | |
e8508a49 MD |
234 | /* |
235 | * Counting nesting within lttng-ust. Used to ensure that calling fork() | |
236 | * from liblttng-ust does not execute the pre/post fork handlers. | |
237 | */ | |
8c90a710 | 238 | static DEFINE_URCU_TLS(int, lttng_ust_nest_count); |
e8508a49 | 239 | |
1ea11eab MD |
240 | /* |
241 | * Info about socket and associated listener thread. | |
242 | */ | |
243 | struct sock_info { | |
11ff9c7d | 244 | const char *name; |
1ea11eab | 245 | pthread_t ust_listener; /* listener thread */ |
46050b1a | 246 | int root_handle; |
eb0e6022 | 247 | int registration_done; |
8d20bf54 | 248 | int allowed; |
44e073f5 | 249 | int global; |
e33f3265 | 250 | int thread_active; |
7fc90dca MD |
251 | |
252 | char sock_path[PATH_MAX]; | |
253 | int socket; | |
32ce8569 | 254 | int notify_socket; |
7fc90dca MD |
255 | |
256 | char wait_shm_path[PATH_MAX]; | |
257 | char *wait_shm_mmap; | |
37dddb65 MD |
258 | /* Keep track of lazy state dump not performed yet. */ |
259 | int statedump_pending; | |
eb0e6022 | 260 | int initial_statedump_done; |
94be38e8 | 261 | /* Keep procname for statedump */ |
0db3d6ee | 262 | char procname[LTTNG_UST_ABI_PROCNAME_LEN]; |
1ea11eab | 263 | }; |
2691221a MD |
264 | |
265 | /* Socket from app (connect) to session daemon (listen) for communication */ | |
95fa2ba4 | 266 | static struct sock_info global_apps = { |
11ff9c7d | 267 | .name = "global", |
44e073f5 | 268 | .global = 1, |
7fc90dca | 269 | |
46050b1a | 270 | .root_handle = -1, |
eb0e6022 | 271 | .registration_done = 0, |
060577e3 | 272 | .allowed = 0, |
e33f3265 | 273 | .thread_active = 0, |
7fc90dca | 274 | |
32ce8569 | 275 | .sock_path = LTTNG_DEFAULT_RUNDIR "/" LTTNG_UST_SOCK_FILENAME, |
7fc90dca | 276 | .socket = -1, |
32ce8569 | 277 | .notify_socket = -1, |
7fc90dca | 278 | |
32ce8569 | 279 | .wait_shm_path = "/" LTTNG_UST_WAIT_FILENAME, |
95c25348 | 280 | |
37dddb65 | 281 | .statedump_pending = 0, |
eb0e6022 | 282 | .initial_statedump_done = 0, |
94be38e8 | 283 | .procname[0] = '\0' |
1ea11eab | 284 | }; |
2691221a MD |
285 | |
286 | /* TODO: allow global_apps_sock_path override */ | |
287 | ||
95fa2ba4 | 288 | static struct sock_info local_apps = { |
11ff9c7d | 289 | .name = "local", |
44e073f5 | 290 | .global = 0, |
46050b1a | 291 | .root_handle = -1, |
eb0e6022 | 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, |
eb0e6022 | 300 | .initial_statedump_done = 0, |
94be38e8 | 301 | .procname[0] = '\0' |
1ea11eab | 302 | }; |
2691221a | 303 | |
37ed587a MD |
304 | static int wait_poll_fallback; |
305 | ||
74d81a6c | 306 | static const char *cmd_name_mapping[] = { |
fd17d7ce MD |
307 | [ LTTNG_UST_ABI_RELEASE ] = "Release", |
308 | [ LTTNG_UST_ABI_SESSION ] = "Create Session", | |
309 | [ LTTNG_UST_ABI_TRACER_VERSION ] = "Get Tracer Version", | |
74d81a6c | 310 | |
fd17d7ce MD |
311 | [ LTTNG_UST_ABI_TRACEPOINT_LIST ] = "Create Tracepoint List", |
312 | [ LTTNG_UST_ABI_WAIT_QUIESCENT ] = "Wait for Quiescent State", | |
313 | [ LTTNG_UST_ABI_REGISTER_DONE ] = "Registration Done", | |
314 | [ LTTNG_UST_ABI_TRACEPOINT_FIELD_LIST ] = "Create Tracepoint Field List", | |
74d81a6c | 315 | |
fd17d7ce | 316 | [ LTTNG_UST_ABI_EVENT_NOTIFIER_GROUP_CREATE ] = "Create event notifier group", |
d8d2416d | 317 | |
74d81a6c | 318 | /* Session FD commands */ |
fd17d7ce MD |
319 | [ LTTNG_UST_ABI_CHANNEL ] = "Create Channel", |
320 | [ LTTNG_UST_ABI_SESSION_START ] = "Start Session", | |
321 | [ LTTNG_UST_ABI_SESSION_STOP ] = "Stop Session", | |
74d81a6c MD |
322 | |
323 | /* Channel FD commands */ | |
fd17d7ce MD |
324 | [ LTTNG_UST_ABI_STREAM ] = "Create Stream", |
325 | [ LTTNG_UST_ABI_EVENT ] = "Create Event", | |
74d81a6c MD |
326 | |
327 | /* Event and Channel FD commands */ | |
fd17d7ce MD |
328 | [ LTTNG_UST_ABI_CONTEXT ] = "Create Context", |
329 | [ LTTNG_UST_ABI_FLUSH_BUFFER ] = "Flush Buffer", | |
74d81a6c MD |
330 | |
331 | /* Event, Channel and Session commands */ | |
fd17d7ce MD |
332 | [ LTTNG_UST_ABI_ENABLE ] = "Enable", |
333 | [ LTTNG_UST_ABI_DISABLE ] = "Disable", | |
74d81a6c MD |
334 | |
335 | /* Tracepoint list commands */ | |
fd17d7ce MD |
336 | [ LTTNG_UST_ABI_TRACEPOINT_LIST_GET ] = "List Next Tracepoint", |
337 | [ LTTNG_UST_ABI_TRACEPOINT_FIELD_LIST_GET ] = "List Next Tracepoint Field", | |
74d81a6c MD |
338 | |
339 | /* Event FD commands */ | |
fd17d7ce MD |
340 | [ LTTNG_UST_ABI_FILTER ] = "Create Filter", |
341 | [ LTTNG_UST_ABI_EXCLUSION ] = "Add exclusions to event", | |
d8d2416d FD |
342 | |
343 | /* Event notifier group commands */ | |
fd17d7ce | 344 | [ LTTNG_UST_ABI_EVENT_NOTIFIER_CREATE ] = "Create event notifier", |
ebabbf58 MD |
345 | |
346 | /* Session and event notifier group commands */ | |
fd17d7ce | 347 | [ LTTNG_UST_ABI_COUNTER ] = "Create Counter", |
ebabbf58 MD |
348 | |
349 | /* Counter commands */ | |
fd17d7ce MD |
350 | [ LTTNG_UST_ABI_COUNTER_GLOBAL ] = "Create Counter Global", |
351 | [ LTTNG_UST_ABI_COUNTER_CPU ] = "Create Counter CPU", | |
74d81a6c MD |
352 | }; |
353 | ||
ff517991 MD |
354 | static const char *str_timeout; |
355 | static int got_timeout_env; | |
356 | ||
060577e3 JR |
357 | static char *get_map_shm(struct sock_info *sock_info); |
358 | ||
3c6f6263 AM |
359 | /* |
360 | * Returns the HOME directory path. Caller MUST NOT free(3) the returned | |
361 | * pointer. | |
362 | */ | |
363 | static | |
364 | const char *get_lttng_home_dir(void) | |
365 | { | |
366 | const char *val; | |
367 | ||
4c41b460 | 368 | val = (const char *) lttng_ust_getenv("LTTNG_HOME"); |
3c6f6263 AM |
369 | if (val != NULL) { |
370 | return val; | |
371 | } | |
4c41b460 | 372 | return (const char *) lttng_ust_getenv("HOME"); |
3c6f6263 AM |
373 | } |
374 | ||
a903623f | 375 | /* |
a9fd951a | 376 | * Force a read (imply TLS allocation for dlopen) of TLS variables. |
a903623f MD |
377 | */ |
378 | static | |
a9fd951a | 379 | void lttng_nest_count_alloc_tls(void) |
a903623f | 380 | { |
8c90a710 | 381 | asm volatile ("" : : "m" (URCU_TLS(lttng_ust_nest_count))); |
a903623f MD |
382 | } |
383 | ||
d58d1454 | 384 | static |
a9fd951a | 385 | void lttng_ust_mutex_nest_alloc_tls(void) |
d58d1454 MD |
386 | { |
387 | asm volatile ("" : : "m" (URCU_TLS(ust_mutex_nest))); | |
388 | } | |
389 | ||
1556a549 | 390 | /* |
a9fd951a | 391 | * Allocate lttng-ust urcu TLS. |
1556a549 MD |
392 | */ |
393 | static | |
a9fd951a | 394 | void lttng_lttng_ust_urcu_alloc_tls(void) |
1556a549 | 395 | { |
10544ee8 | 396 | (void) lttng_ust_urcu_read_ongoing(); |
1556a549 MD |
397 | } |
398 | ||
a9fd951a | 399 | void lttng_ust_alloc_tls(void) |
c362addf | 400 | { |
a9fd951a MJ |
401 | lttng_lttng_ust_urcu_alloc_tls(); |
402 | lttng_ringbuffer_alloc_tls(); | |
403 | lttng_vtid_alloc_tls(); | |
404 | lttng_nest_count_alloc_tls(); | |
405 | lttng_procname_alloc_tls(); | |
406 | lttng_ust_mutex_nest_alloc_tls(); | |
407 | lttng_ust_perf_counter_alloc_tls(); | |
cf914d16 | 408 | lttng_ust_common_alloc_tls(); |
a9fd951a MJ |
409 | lttng_cgroup_ns_alloc_tls(); |
410 | lttng_ipc_ns_alloc_tls(); | |
411 | lttng_net_ns_alloc_tls(); | |
412 | lttng_time_ns_alloc_tls(); | |
413 | lttng_uts_ns_alloc_tls(); | |
414 | lttng_ust_ring_buffer_client_discard_alloc_tls(); | |
415 | lttng_ust_ring_buffer_client_discard_rt_alloc_tls(); | |
416 | lttng_ust_ring_buffer_client_overwrite_alloc_tls(); | |
417 | lttng_ust_ring_buffer_client_overwrite_rt_alloc_tls(); | |
14e0a135 MD |
418 | } |
419 | ||
420 | /* | |
421 | * LTTng-UST uses Global Dynamic model TLS variables rather than IE | |
422 | * model because many versions of glibc don't preallocate a pool large | |
423 | * enough for TLS variables IE model defined in other shared libraries, | |
424 | * and causes issues when using LTTng-UST for Java tracing. | |
425 | * | |
426 | * Because of this use of Global Dynamic TLS variables, users wishing to | |
427 | * trace from signal handlers need to explicitly trigger the lazy | |
428 | * allocation of those variables for each thread before using them. | |
429 | * This can be triggered by calling lttng_ust_init_thread(). | |
430 | */ | |
431 | void lttng_ust_init_thread(void) | |
432 | { | |
433 | /* | |
434 | * Because those TLS variables are global dynamic, we need to | |
435 | * ensure those are initialized before a signal handler nesting over | |
436 | * this thread attempts to use them. | |
437 | */ | |
a9fd951a | 438 | lttng_ust_alloc_tls(); |
c362addf MD |
439 | } |
440 | ||
32ce8569 MD |
441 | int lttng_get_notify_socket(void *owner) |
442 | { | |
443 | struct sock_info *info = owner; | |
444 | ||
445 | return info->notify_socket; | |
446 | } | |
447 | ||
94be38e8 | 448 | |
94be38e8 JR |
449 | char* lttng_ust_sockinfo_get_procname(void *owner) |
450 | { | |
451 | struct sock_info *info = owner; | |
452 | ||
453 | return info->procname; | |
454 | } | |
455 | ||
74d81a6c MD |
456 | static |
457 | void print_cmd(int cmd, int handle) | |
458 | { | |
459 | const char *cmd_name = "Unknown"; | |
460 | ||
fd67a004 MD |
461 | if (cmd >= 0 && cmd < LTTNG_ARRAY_SIZE(cmd_name_mapping) |
462 | && cmd_name_mapping[cmd]) { | |
74d81a6c MD |
463 | cmd_name = cmd_name_mapping[cmd]; |
464 | } | |
fd67a004 MD |
465 | DBG("Message Received \"%s\" (%d), Handle \"%s\" (%d)", |
466 | cmd_name, cmd, | |
74d81a6c MD |
467 | lttng_ust_obj_get_name(handle), handle); |
468 | } | |
469 | ||
060577e3 JR |
470 | static |
471 | int setup_global_apps(void) | |
472 | { | |
473 | int ret = 0; | |
474 | assert(!global_apps.wait_shm_mmap); | |
475 | ||
476 | global_apps.wait_shm_mmap = get_map_shm(&global_apps); | |
477 | if (!global_apps.wait_shm_mmap) { | |
478 | WARN("Unable to get map shm for global apps. Disabling LTTng-UST global tracing."); | |
479 | global_apps.allowed = 0; | |
480 | ret = -EIO; | |
481 | goto error; | |
482 | } | |
483 | ||
484 | global_apps.allowed = 1; | |
0db3d6ee | 485 | lttng_pthread_getname_np(global_apps.procname, LTTNG_UST_ABI_PROCNAME_LEN); |
060577e3 JR |
486 | error: |
487 | return ret; | |
488 | } | |
2691221a | 489 | static |
8d20bf54 | 490 | int setup_local_apps(void) |
2691221a | 491 | { |
060577e3 | 492 | int ret = 0; |
2691221a | 493 | const char *home_dir; |
7fc90dca | 494 | uid_t uid; |
2691221a | 495 | |
060577e3 JR |
496 | assert(!local_apps.wait_shm_mmap); |
497 | ||
7fc90dca | 498 | uid = getuid(); |
8d20bf54 MD |
499 | /* |
500 | * Disallow per-user tracing for setuid binaries. | |
501 | */ | |
7fc90dca | 502 | if (uid != geteuid()) { |
9ec6895c | 503 | assert(local_apps.allowed == 0); |
060577e3 JR |
504 | ret = 0; |
505 | goto end; | |
8d20bf54 | 506 | } |
3c6f6263 | 507 | home_dir = get_lttng_home_dir(); |
9ec6895c MD |
508 | if (!home_dir) { |
509 | WARN("HOME environment variable not set. Disabling LTTng-UST per-user tracing."); | |
510 | assert(local_apps.allowed == 0); | |
060577e3 JR |
511 | ret = -ENOENT; |
512 | goto end; | |
9ec6895c MD |
513 | } |
514 | local_apps.allowed = 1; | |
32ce8569 MD |
515 | snprintf(local_apps.sock_path, PATH_MAX, "%s/%s/%s", |
516 | home_dir, | |
517 | LTTNG_DEFAULT_HOME_RUNDIR, | |
518 | LTTNG_UST_SOCK_FILENAME); | |
519 | snprintf(local_apps.wait_shm_path, PATH_MAX, "/%s-%u", | |
520 | LTTNG_UST_WAIT_FILENAME, | |
521 | uid); | |
060577e3 JR |
522 | |
523 | local_apps.wait_shm_mmap = get_map_shm(&local_apps); | |
524 | if (!local_apps.wait_shm_mmap) { | |
525 | WARN("Unable to get map shm for local apps. Disabling LTTng-UST per-user tracing."); | |
526 | local_apps.allowed = 0; | |
527 | ret = -EIO; | |
528 | goto end; | |
529 | } | |
94be38e8 | 530 | |
0db3d6ee | 531 | lttng_pthread_getname_np(local_apps.procname, LTTNG_UST_ABI_PROCNAME_LEN); |
060577e3 JR |
532 | end: |
533 | return ret; | |
2691221a MD |
534 | } |
535 | ||
ff517991 | 536 | /* |
451d66b2 | 537 | * Get socket timeout, in ms. |
28515902 | 538 | * -1: wait forever. 0: don't wait. >0: timeout, in ms. |
ff517991 MD |
539 | */ |
540 | static | |
541 | long get_timeout(void) | |
542 | { | |
543 | long constructor_delay_ms = LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS; | |
544 | ||
545 | if (!got_timeout_env) { | |
4c41b460 | 546 | str_timeout = lttng_ust_getenv("LTTNG_UST_REGISTER_TIMEOUT"); |
ff517991 MD |
547 | got_timeout_env = 1; |
548 | } | |
549 | if (str_timeout) | |
550 | constructor_delay_ms = strtol(str_timeout, NULL, 10); | |
5cf81d53 MD |
551 | /* All negative values are considered as "-1". */ |
552 | if (constructor_delay_ms < -1) | |
553 | constructor_delay_ms = -1; | |
ff517991 MD |
554 | return constructor_delay_ms; |
555 | } | |
556 | ||
451d66b2 | 557 | /* Timeout for notify socket send and recv. */ |
ff517991 MD |
558 | static |
559 | long get_notify_sock_timeout(void) | |
560 | { | |
561 | return get_timeout(); | |
562 | } | |
563 | ||
451d66b2 MD |
564 | /* Timeout for connecting to cmd and notify sockets. */ |
565 | static | |
566 | long get_connect_sock_timeout(void) | |
567 | { | |
568 | return get_timeout(); | |
569 | } | |
570 | ||
ff517991 | 571 | /* |
28515902 | 572 | * Return values: -1: wait forever. 0: don't wait. 1: timeout wait. |
ff517991 MD |
573 | */ |
574 | static | |
575 | int get_constructor_timeout(struct timespec *constructor_timeout) | |
576 | { | |
577 | long constructor_delay_ms; | |
578 | int ret; | |
579 | ||
580 | constructor_delay_ms = get_timeout(); | |
581 | ||
582 | switch (constructor_delay_ms) { | |
583 | case -1:/* fall-through */ | |
584 | case 0: | |
585 | return constructor_delay_ms; | |
586 | default: | |
587 | break; | |
588 | } | |
589 | ||
590 | /* | |
591 | * If we are unable to find the current time, don't wait. | |
592 | */ | |
593 | ret = clock_gettime(CLOCK_REALTIME, constructor_timeout); | |
594 | if (ret) { | |
28515902 JG |
595 | /* Don't wait. */ |
596 | return 0; | |
ff517991 MD |
597 | } |
598 | constructor_timeout->tv_sec += constructor_delay_ms / 1000UL; | |
599 | constructor_timeout->tv_nsec += | |
600 | (constructor_delay_ms % 1000UL) * 1000000UL; | |
601 | if (constructor_timeout->tv_nsec >= 1000000000UL) { | |
602 | constructor_timeout->tv_sec++; | |
603 | constructor_timeout->tv_nsec -= 1000000000UL; | |
604 | } | |
28515902 | 605 | /* Timeout wait (constructor_delay_ms). */ |
ff517991 MD |
606 | return 1; |
607 | } | |
608 | ||
6f97f9c2 | 609 | static |
b2c5f61a | 610 | void get_allow_blocking(void) |
6f97f9c2 | 611 | { |
b2c5f61a | 612 | const char *str_allow_blocking = |
4c41b460 | 613 | lttng_ust_getenv("LTTNG_UST_ALLOW_BLOCKING"); |
b2c5f61a MD |
614 | |
615 | if (str_allow_blocking) { | |
616 | DBG("%s environment variable is set", | |
617 | "LTTNG_UST_ALLOW_BLOCKING"); | |
618 | lttng_ust_ringbuffer_set_allow_blocking(); | |
6f97f9c2 MD |
619 | } |
620 | } | |
621 | ||
2691221a | 622 | static |
249cffb5 | 623 | int register_to_sessiond(int socket, enum lttng_ust_ctl_socket_type type) |
2691221a | 624 | { |
32ce8569 MD |
625 | return ustcomm_send_reg_msg(socket, |
626 | type, | |
627 | CAA_BITS_PER_LONG, | |
dc325c1d MJ |
628 | lttng_ust_rb_alignof(uint8_t) * CHAR_BIT, |
629 | lttng_ust_rb_alignof(uint16_t) * CHAR_BIT, | |
630 | lttng_ust_rb_alignof(uint32_t) * CHAR_BIT, | |
631 | lttng_ust_rb_alignof(uint64_t) * CHAR_BIT, | |
632 | lttng_ust_rb_alignof(unsigned long) * CHAR_BIT); | |
2691221a MD |
633 | } |
634 | ||
d9e99d10 | 635 | static |
57773204 | 636 | int send_reply(int sock, struct ustcomm_ust_reply *lur) |
d9e99d10 | 637 | { |
9eb62b9c | 638 | ssize_t len; |
d3a492d1 | 639 | |
57773204 | 640 | len = ustcomm_send_unix_sock(sock, lur, sizeof(*lur)); |
d3a492d1 | 641 | switch (len) { |
a4be8962 | 642 | case sizeof(*lur): |
d3a492d1 MD |
643 | DBG("message successfully sent"); |
644 | return 0; | |
7bc53e94 MD |
645 | default: |
646 | if (len == -ECONNRESET) { | |
647 | DBG("remote end closed connection"); | |
d3a492d1 MD |
648 | return 0; |
649 | } | |
7bc53e94 MD |
650 | if (len < 0) |
651 | return len; | |
652 | DBG("incorrect message size: %zd", len); | |
653 | return -EINVAL; | |
d3a492d1 MD |
654 | } |
655 | } | |
656 | ||
657 | static | |
eb0e6022 | 658 | void decrement_sem_count(unsigned int count) |
11ff9c7d MD |
659 | { |
660 | int ret; | |
661 | ||
eb0e6022 GAPG |
662 | assert(uatomic_read(&sem_count) >= count); |
663 | ||
56cd7e2f | 664 | if (uatomic_read(&sem_count) <= 0) { |
eb0e6022 | 665 | return; |
56cd7e2f | 666 | } |
eb0e6022 GAPG |
667 | |
668 | ret = uatomic_add_return(&sem_count, -count); | |
95259bd0 MD |
669 | if (ret == 0) { |
670 | ret = sem_post(&constructor_wait); | |
671 | assert(!ret); | |
672 | } | |
eb0e6022 GAPG |
673 | } |
674 | ||
675 | static | |
676 | int handle_register_done(struct sock_info *sock_info) | |
677 | { | |
678 | if (sock_info->registration_done) | |
679 | return 0; | |
680 | sock_info->registration_done = 1; | |
681 | ||
682 | decrement_sem_count(1); | |
04682184 MD |
683 | if (!sock_info->statedump_pending) { |
684 | sock_info->initial_statedump_done = 1; | |
685 | decrement_sem_count(1); | |
686 | } | |
eb0e6022 GAPG |
687 | |
688 | return 0; | |
689 | } | |
690 | ||
691 | static | |
692 | int handle_register_failed(struct sock_info *sock_info) | |
693 | { | |
694 | if (sock_info->registration_done) | |
695 | return 0; | |
696 | sock_info->registration_done = 1; | |
697 | sock_info->initial_statedump_done = 1; | |
698 | ||
699 | decrement_sem_count(2); | |
700 | ||
11ff9c7d MD |
701 | return 0; |
702 | } | |
703 | ||
37dddb65 MD |
704 | /* |
705 | * Only execute pending statedump after the constructor semaphore has | |
eb0e6022 GAPG |
706 | * been posted by the current listener thread. This means statedump will |
707 | * only be performed after the "registration done" command is received | |
708 | * from this thread's session daemon. | |
37dddb65 MD |
709 | * |
710 | * This ensures we don't run into deadlock issues with the dynamic | |
711 | * loader mutex, which is held while the constructor is called and | |
712 | * waiting on the constructor semaphore. All operations requiring this | |
713 | * dynamic loader lock need to be postponed using this mechanism. | |
eb0e6022 GAPG |
714 | * |
715 | * In a scenario with two session daemons connected to the application, | |
716 | * it is possible that the first listener thread which receives the | |
717 | * registration done command issues its statedump while the dynamic | |
718 | * loader lock is still held by the application constructor waiting on | |
719 | * the semaphore. It will however be allowed to proceed when the | |
720 | * second session daemon sends the registration done command to the | |
721 | * second listener thread. This situation therefore does not produce | |
722 | * a deadlock. | |
37dddb65 MD |
723 | */ |
724 | static | |
725 | void handle_pending_statedump(struct sock_info *sock_info) | |
726 | { | |
eb0e6022 | 727 | if (sock_info->registration_done && sock_info->statedump_pending) { |
37dddb65 | 728 | sock_info->statedump_pending = 0; |
2932a87f | 729 | pthread_mutex_lock(&ust_fork_mutex); |
37dddb65 | 730 | lttng_handle_pending_statedump(sock_info); |
458d678c | 731 | pthread_mutex_unlock(&ust_fork_mutex); |
eb0e6022 GAPG |
732 | |
733 | if (!sock_info->initial_statedump_done) { | |
734 | sock_info->initial_statedump_done = 1; | |
735 | decrement_sem_count(1); | |
736 | } | |
37dddb65 MD |
737 | } |
738 | } | |
739 | ||
6a6ef048 FD |
740 | static inline |
741 | const char *bytecode_type_str(uint32_t cmd) | |
742 | { | |
743 | switch (cmd) { | |
fd17d7ce | 744 | case LTTNG_UST_ABI_CAPTURE: |
d37ecb3f | 745 | return "capture"; |
fd17d7ce | 746 | case LTTNG_UST_ABI_FILTER: |
6a6ef048 FD |
747 | return "filter"; |
748 | default: | |
749 | abort(); | |
750 | } | |
751 | } | |
752 | ||
753 | static | |
754 | int handle_bytecode_recv(struct sock_info *sock_info, | |
755 | int sock, struct ustcomm_ust_msg *lum) | |
756 | { | |
ab89263e | 757 | struct lttng_ust_bytecode_node *bytecode = NULL; |
22c30e27 | 758 | enum lttng_ust_bytecode_type type; |
fd17d7ce | 759 | const struct lttng_ust_abi_objd_ops *ops; |
6a6ef048 FD |
760 | uint32_t data_size, data_size_max, reloc_offset; |
761 | uint64_t seqnum; | |
762 | ssize_t len; | |
763 | int ret = 0; | |
764 | ||
765 | switch (lum->cmd) { | |
fd17d7ce | 766 | case LTTNG_UST_ABI_FILTER: |
22c30e27 | 767 | type = LTTNG_UST_BYTECODE_TYPE_FILTER; |
6a6ef048 | 768 | data_size = lum->u.filter.data_size; |
fd17d7ce | 769 | data_size_max = LTTNG_UST_ABI_FILTER_BYTECODE_MAX_LEN; |
6a6ef048 FD |
770 | reloc_offset = lum->u.filter.reloc_offset; |
771 | seqnum = lum->u.filter.seqnum; | |
772 | break; | |
fd17d7ce | 773 | case LTTNG_UST_ABI_CAPTURE: |
22c30e27 | 774 | type = LTTNG_UST_BYTECODE_TYPE_CAPTURE; |
d37ecb3f | 775 | data_size = lum->u.capture.data_size; |
fd17d7ce | 776 | data_size_max = LTTNG_UST_ABI_CAPTURE_BYTECODE_MAX_LEN; |
d37ecb3f FD |
777 | reloc_offset = lum->u.capture.reloc_offset; |
778 | seqnum = lum->u.capture.seqnum; | |
779 | break; | |
6a6ef048 FD |
780 | default: |
781 | abort(); | |
782 | } | |
783 | ||
784 | if (data_size > data_size_max) { | |
785 | ERR("Bytecode %s data size is too large: %u bytes", | |
786 | bytecode_type_str(lum->cmd), data_size); | |
787 | ret = -EINVAL; | |
788 | goto end; | |
789 | } | |
790 | ||
791 | if (reloc_offset > data_size) { | |
792 | ERR("Bytecode %s reloc offset %u is not within data", | |
793 | bytecode_type_str(lum->cmd), reloc_offset); | |
794 | ret = -EINVAL; | |
795 | goto end; | |
796 | } | |
797 | ||
798 | /* Allocate the structure AND the `data[]` field. */ | |
799 | bytecode = zmalloc(sizeof(*bytecode) + data_size); | |
800 | if (!bytecode) { | |
801 | ret = -ENOMEM; | |
802 | goto end; | |
803 | } | |
804 | ||
805 | bytecode->bc.len = data_size; | |
806 | bytecode->bc.reloc_offset = reloc_offset; | |
807 | bytecode->bc.seqnum = seqnum; | |
808 | bytecode->type = type; | |
809 | ||
810 | len = ustcomm_recv_unix_sock(sock, bytecode->bc.data, bytecode->bc.len); | |
811 | switch (len) { | |
812 | case 0: /* orderly shutdown */ | |
813 | ret = 0; | |
ab89263e | 814 | goto end; |
6a6ef048 FD |
815 | default: |
816 | if (len == bytecode->bc.len) { | |
817 | DBG("Bytecode %s data received", | |
818 | bytecode_type_str(lum->cmd)); | |
819 | break; | |
820 | } else if (len < 0) { | |
821 | DBG("Receive failed from lttng-sessiond with errno %d", | |
822 | (int) -len); | |
823 | if (len == -ECONNRESET) { | |
824 | ERR("%s remote end closed connection", | |
825 | sock_info->name); | |
826 | ret = len; | |
ab89263e | 827 | goto end; |
6a6ef048 FD |
828 | } |
829 | ret = len; | |
ab89263e | 830 | goto end; |
6a6ef048 FD |
831 | } else { |
832 | DBG("Incorrect %s bytecode data message size: %zd", | |
833 | bytecode_type_str(lum->cmd), len); | |
834 | ret = -EINVAL; | |
ab89263e | 835 | goto end; |
6a6ef048 FD |
836 | } |
837 | } | |
838 | ||
fd17d7ce | 839 | ops = lttng_ust_abi_objd_ops(lum->handle); |
6a6ef048 FD |
840 | if (!ops) { |
841 | ret = -ENOENT; | |
ab89263e | 842 | goto end; |
6a6ef048 FD |
843 | } |
844 | ||
ab89263e | 845 | if (ops->cmd) |
6a6ef048 | 846 | ret = ops->cmd(lum->handle, lum->cmd, |
ab89263e | 847 | (unsigned long) &bytecode, |
6a6ef048 | 848 | NULL, sock_info); |
ab89263e | 849 | else |
6a6ef048 | 850 | ret = -ENOSYS; |
6a6ef048 | 851 | |
6a6ef048 | 852 | end: |
ab89263e | 853 | free(bytecode); |
6a6ef048 FD |
854 | return ret; |
855 | } | |
856 | ||
11ff9c7d MD |
857 | static |
858 | int handle_message(struct sock_info *sock_info, | |
57773204 | 859 | int sock, struct ustcomm_ust_msg *lum) |
d3a492d1 | 860 | { |
1ea11eab | 861 | int ret = 0; |
fd17d7ce | 862 | const struct lttng_ust_abi_objd_ops *ops; |
57773204 | 863 | struct ustcomm_ust_reply lur; |
fd17d7ce MD |
864 | union lttng_ust_abi_args args; |
865 | char ctxstr[LTTNG_UST_ABI_SYM_NAME_LEN]; /* App context string. */ | |
40003310 | 866 | ssize_t len; |
1ea11eab | 867 | |
46050b1a MD |
868 | memset(&lur, 0, sizeof(lur)); |
869 | ||
3327ac33 | 870 | if (ust_lock()) { |
74d81a6c | 871 | ret = -LTTNG_UST_ERR_EXITING; |
0dafcd63 | 872 | goto error; |
1ea11eab | 873 | } |
9eb62b9c | 874 | |
fd17d7ce | 875 | ops = lttng_ust_abi_objd_ops(lum->handle); |
46050b1a MD |
876 | if (!ops) { |
877 | ret = -ENOENT; | |
0dafcd63 | 878 | goto error; |
1ea11eab | 879 | } |
46050b1a MD |
880 | |
881 | switch (lum->cmd) { | |
fd17d7ce MD |
882 | case LTTNG_UST_ABI_REGISTER_DONE: |
883 | if (lum->handle == LTTNG_UST_ABI_ROOT_HANDLE) | |
edaa1431 | 884 | ret = handle_register_done(sock_info); |
11ff9c7d MD |
885 | else |
886 | ret = -EINVAL; | |
887 | break; | |
fd17d7ce MD |
888 | case LTTNG_UST_ABI_RELEASE: |
889 | if (lum->handle == LTTNG_UST_ABI_ROOT_HANDLE) | |
46050b1a MD |
890 | ret = -EPERM; |
891 | else | |
fd17d7ce | 892 | ret = lttng_ust_abi_objd_unref(lum->handle, 1); |
d9e99d10 | 893 | break; |
fd17d7ce MD |
894 | case LTTNG_UST_ABI_CAPTURE: |
895 | case LTTNG_UST_ABI_FILTER: | |
6a6ef048 FD |
896 | ret = handle_bytecode_recv(sock_info, sock, lum); |
897 | if (ret) | |
2734ca65 | 898 | goto error; |
2d78951a | 899 | break; |
fd17d7ce | 900 | case LTTNG_UST_ABI_EXCLUSION: |
86e36163 JI |
901 | { |
902 | /* Receive exclusion names */ | |
903 | struct lttng_ust_excluder_node *node; | |
904 | unsigned int count; | |
905 | ||
906 | count = lum->u.exclusion.count; | |
907 | if (count == 0) { | |
908 | /* There are no names to read */ | |
909 | ret = 0; | |
910 | goto error; | |
911 | } | |
912 | node = zmalloc(sizeof(*node) + | |
fd17d7ce | 913 | count * LTTNG_UST_ABI_SYM_NAME_LEN); |
86e36163 JI |
914 | if (!node) { |
915 | ret = -ENOMEM; | |
916 | goto error; | |
917 | } | |
918 | node->excluder.count = count; | |
919 | len = ustcomm_recv_unix_sock(sock, node->excluder.names, | |
fd17d7ce | 920 | count * LTTNG_UST_ABI_SYM_NAME_LEN); |
86e36163 JI |
921 | switch (len) { |
922 | case 0: /* orderly shutdown */ | |
923 | ret = 0; | |
924 | free(node); | |
925 | goto error; | |
926 | default: | |
fd17d7ce | 927 | if (len == count * LTTNG_UST_ABI_SYM_NAME_LEN) { |
86e36163 JI |
928 | DBG("Exclusion data received"); |
929 | break; | |
930 | } else if (len < 0) { | |
931 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
932 | if (len == -ECONNRESET) { | |
933 | ERR("%s remote end closed connection", sock_info->name); | |
934 | ret = len; | |
935 | free(node); | |
936 | goto error; | |
937 | } | |
938 | ret = len; | |
939 | free(node); | |
0dafcd63 | 940 | goto error; |
86e36163 JI |
941 | } else { |
942 | DBG("Incorrect exclusion data message size: %zd", len); | |
943 | ret = -EINVAL; | |
944 | free(node); | |
0dafcd63 | 945 | goto error; |
86e36163 JI |
946 | } |
947 | } | |
e9fe6aad | 948 | if (ops->cmd) |
86e36163 | 949 | ret = ops->cmd(lum->handle, lum->cmd, |
e9fe6aad | 950 | (unsigned long) &node, |
86e36163 | 951 | &args, sock_info); |
e9fe6aad | 952 | else |
86e36163 | 953 | ret = -ENOSYS; |
e9fe6aad | 954 | free(node); |
86e36163 JI |
955 | break; |
956 | } | |
fd17d7ce | 957 | case LTTNG_UST_ABI_EVENT_NOTIFIER_GROUP_CREATE: |
d8d2416d | 958 | { |
f52e5902 | 959 | int event_notifier_notif_fd, close_ret; |
d8d2416d FD |
960 | |
961 | len = ustcomm_recv_event_notifier_notif_fd_from_sessiond(sock, | |
962 | &event_notifier_notif_fd); | |
963 | switch (len) { | |
964 | case 0: /* orderly shutdown */ | |
965 | ret = 0; | |
966 | goto error; | |
967 | case 1: | |
968 | break; | |
969 | default: | |
970 | if (len < 0) { | |
971 | DBG("Receive failed from lttng-sessiond with errno %d", | |
972 | (int) -len); | |
973 | if (len == -ECONNRESET) { | |
974 | ERR("%s remote end closed connection", | |
975 | sock_info->name); | |
976 | ret = len; | |
977 | goto error; | |
978 | } | |
979 | ret = len; | |
980 | goto error; | |
981 | } else { | |
982 | DBG("Incorrect event notifier fd message size: %zd", | |
983 | len); | |
984 | ret = -EINVAL; | |
985 | goto error; | |
986 | } | |
987 | } | |
988 | args.event_notifier_handle.event_notifier_notif_fd = | |
989 | event_notifier_notif_fd; | |
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; | |
f52e5902 MD |
996 | if (args.event_notifier_handle.event_notifier_notif_fd >= 0) { |
997 | lttng_ust_lock_fd_tracker(); | |
998 | close_ret = close(args.event_notifier_handle.event_notifier_notif_fd); | |
999 | lttng_ust_unlock_fd_tracker(); | |
1000 | if (close_ret) | |
1001 | PERROR("close"); | |
1002 | } | |
d8d2416d FD |
1003 | break; |
1004 | } | |
fd17d7ce | 1005 | case LTTNG_UST_ABI_CHANNEL: |
74d81a6c MD |
1006 | { |
1007 | void *chan_data; | |
ff0f5728 | 1008 | int wakeup_fd; |
74d81a6c MD |
1009 | |
1010 | len = ustcomm_recv_channel_from_sessiond(sock, | |
ff0f5728 MD |
1011 | &chan_data, lum->u.channel.len, |
1012 | &wakeup_fd); | |
74d81a6c MD |
1013 | switch (len) { |
1014 | case 0: /* orderly shutdown */ | |
1015 | ret = 0; | |
1016 | goto error; | |
1017 | default: | |
1018 | if (len == lum->u.channel.len) { | |
1019 | DBG("channel data received"); | |
1020 | break; | |
1021 | } else if (len < 0) { | |
1022 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
1023 | if (len == -ECONNRESET) { | |
1024 | ERR("%s remote end closed connection", sock_info->name); | |
1025 | ret = len; | |
1026 | goto error; | |
1027 | } | |
1028 | ret = len; | |
0dafcd63 | 1029 | goto error; |
74d81a6c MD |
1030 | } else { |
1031 | DBG("incorrect channel data message size: %zd", len); | |
1032 | ret = -EINVAL; | |
0dafcd63 | 1033 | goto error; |
74d81a6c MD |
1034 | } |
1035 | } | |
1036 | args.channel.chan_data = chan_data; | |
ff0f5728 | 1037 | args.channel.wakeup_fd = wakeup_fd; |
74d81a6c MD |
1038 | if (ops->cmd) |
1039 | ret = ops->cmd(lum->handle, lum->cmd, | |
1040 | (unsigned long) &lum->u, | |
1041 | &args, sock_info); | |
1042 | else | |
1043 | ret = -ENOSYS; | |
867942fd MD |
1044 | if (args.channel.wakeup_fd >= 0) { |
1045 | int close_ret; | |
1046 | ||
1047 | lttng_ust_lock_fd_tracker(); | |
1048 | close_ret = close(args.channel.wakeup_fd); | |
1049 | lttng_ust_unlock_fd_tracker(); | |
1050 | args.channel.wakeup_fd = -1; | |
1051 | if (close_ret) | |
1052 | PERROR("close"); | |
1053 | } | |
1054 | free(args.channel.chan_data); | |
74d81a6c MD |
1055 | break; |
1056 | } | |
fd17d7ce | 1057 | case LTTNG_UST_ABI_STREAM: |
74d81a6c | 1058 | { |
118c051e MD |
1059 | int close_ret; |
1060 | ||
74d81a6c MD |
1061 | /* Receive shm_fd, wakeup_fd */ |
1062 | ret = ustcomm_recv_stream_from_sessiond(sock, | |
61e520fb | 1063 | NULL, |
74d81a6c MD |
1064 | &args.stream.shm_fd, |
1065 | &args.stream.wakeup_fd); | |
1066 | if (ret) { | |
0dafcd63 | 1067 | goto error; |
74d81a6c | 1068 | } |
973eac63 | 1069 | |
74d81a6c MD |
1070 | if (ops->cmd) |
1071 | ret = ops->cmd(lum->handle, lum->cmd, | |
1072 | (unsigned long) &lum->u, | |
1073 | &args, sock_info); | |
1074 | else | |
1075 | ret = -ENOSYS; | |
118c051e MD |
1076 | if (args.stream.shm_fd >= 0) { |
1077 | lttng_ust_lock_fd_tracker(); | |
1078 | close_ret = close(args.stream.shm_fd); | |
1079 | lttng_ust_unlock_fd_tracker(); | |
1080 | args.stream.shm_fd = -1; | |
1081 | if (close_ret) | |
1082 | PERROR("close"); | |
1083 | } | |
1084 | if (args.stream.wakeup_fd >= 0) { | |
1085 | lttng_ust_lock_fd_tracker(); | |
1086 | close_ret = close(args.stream.wakeup_fd); | |
1087 | lttng_ust_unlock_fd_tracker(); | |
1088 | args.stream.wakeup_fd = -1; | |
1089 | if (close_ret) | |
1090 | PERROR("close"); | |
1091 | } | |
74d81a6c MD |
1092 | break; |
1093 | } | |
fd17d7ce | 1094 | case LTTNG_UST_ABI_CONTEXT: |
8e696cfa | 1095 | switch (lum->u.context.ctx) { |
fd17d7ce | 1096 | case LTTNG_UST_ABI_CONTEXT_APP_CONTEXT: |
8e696cfa MD |
1097 | { |
1098 | char *p; | |
1099 | size_t ctxlen, recvlen; | |
1100 | ||
1101 | ctxlen = strlen("$app.") + lum->u.context.u.app_ctx.provider_name_len - 1 | |
1102 | + strlen(":") + lum->u.context.u.app_ctx.ctx_name_len; | |
fd17d7ce | 1103 | if (ctxlen >= LTTNG_UST_ABI_SYM_NAME_LEN) { |
8e696cfa MD |
1104 | ERR("Application context string length size is too large: %zu bytes", |
1105 | ctxlen); | |
1106 | ret = -EINVAL; | |
1107 | goto error; | |
1108 | } | |
1109 | strcpy(ctxstr, "$app."); | |
1110 | p = &ctxstr[strlen("$app.")]; | |
1111 | recvlen = ctxlen - strlen("$app."); | |
1112 | len = ustcomm_recv_unix_sock(sock, p, recvlen); | |
1113 | switch (len) { | |
1114 | case 0: /* orderly shutdown */ | |
1115 | ret = 0; | |
1116 | goto error; | |
1117 | default: | |
1118 | if (len == recvlen) { | |
1119 | DBG("app context data received"); | |
1120 | break; | |
1121 | } else if (len < 0) { | |
1122 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
1123 | if (len == -ECONNRESET) { | |
1124 | ERR("%s remote end closed connection", sock_info->name); | |
1125 | ret = len; | |
1126 | goto error; | |
1127 | } | |
1128 | ret = len; | |
1129 | goto error; | |
1130 | } else { | |
1131 | DBG("incorrect app context data message size: %zd", len); | |
1132 | ret = -EINVAL; | |
1133 | goto error; | |
1134 | } | |
1135 | } | |
1136 | /* Put : between provider and ctxname. */ | |
1137 | p[lum->u.context.u.app_ctx.provider_name_len - 1] = ':'; | |
1138 | args.app_context.ctxname = ctxstr; | |
1139 | break; | |
1140 | } | |
1141 | default: | |
1142 | break; | |
1143 | } | |
1144 | if (ops->cmd) { | |
1145 | ret = ops->cmd(lum->handle, lum->cmd, | |
1146 | (unsigned long) &lum->u, | |
1147 | &args, sock_info); | |
1148 | } else { | |
1149 | ret = -ENOSYS; | |
1150 | } | |
1151 | break; | |
fd17d7ce | 1152 | case LTTNG_UST_ABI_COUNTER: |
ebabbf58 MD |
1153 | { |
1154 | void *counter_data; | |
1155 | ||
1156 | len = ustcomm_recv_counter_from_sessiond(sock, | |
1157 | &counter_data, lum->u.counter.len); | |
1158 | switch (len) { | |
1159 | case 0: /* orderly shutdown */ | |
1160 | ret = 0; | |
1161 | goto error; | |
1162 | default: | |
1163 | if (len == lum->u.counter.len) { | |
1164 | DBG("counter data received"); | |
1165 | break; | |
1166 | } else if (len < 0) { | |
1167 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
1168 | if (len == -ECONNRESET) { | |
1169 | ERR("%s remote end closed connection", sock_info->name); | |
1170 | ret = len; | |
1171 | goto error; | |
1172 | } | |
1173 | ret = len; | |
1174 | goto error; | |
1175 | } else { | |
1176 | DBG("incorrect counter data message size: %zd", len); | |
1177 | ret = -EINVAL; | |
1178 | goto error; | |
1179 | } | |
1180 | } | |
1181 | args.counter.counter_data = counter_data; | |
1182 | if (ops->cmd) | |
1183 | ret = ops->cmd(lum->handle, lum->cmd, | |
1184 | (unsigned long) &lum->u, | |
1185 | &args, sock_info); | |
1186 | else | |
1187 | ret = -ENOSYS; | |
d61ad9ef | 1188 | free(args.counter.counter_data); |
ebabbf58 MD |
1189 | break; |
1190 | } | |
fd17d7ce | 1191 | case LTTNG_UST_ABI_COUNTER_GLOBAL: |
ebabbf58 MD |
1192 | { |
1193 | /* Receive shm_fd */ | |
1194 | ret = ustcomm_recv_counter_shm_from_sessiond(sock, | |
1195 | &args.counter_shm.shm_fd); | |
1196 | if (ret) { | |
1197 | goto error; | |
1198 | } | |
1199 | ||
1200 | if (ops->cmd) | |
1201 | ret = ops->cmd(lum->handle, lum->cmd, | |
1202 | (unsigned long) &lum->u, | |
1203 | &args, sock_info); | |
1204 | else | |
1205 | ret = -ENOSYS; | |
d61ad9ef MD |
1206 | if (args.counter_shm.shm_fd >= 0) { |
1207 | int close_ret; | |
1208 | ||
1209 | lttng_ust_lock_fd_tracker(); | |
1210 | close_ret = close(args.counter_shm.shm_fd); | |
1211 | lttng_ust_unlock_fd_tracker(); | |
1212 | args.counter_shm.shm_fd = -1; | |
1213 | if (close_ret) | |
1214 | PERROR("close"); | |
1215 | } | |
ebabbf58 MD |
1216 | break; |
1217 | } | |
fd17d7ce | 1218 | case LTTNG_UST_ABI_COUNTER_CPU: |
ebabbf58 MD |
1219 | { |
1220 | /* Receive shm_fd */ | |
1221 | ret = ustcomm_recv_counter_shm_from_sessiond(sock, | |
1222 | &args.counter_shm.shm_fd); | |
1223 | if (ret) { | |
1224 | goto error; | |
1225 | } | |
1226 | ||
1227 | if (ops->cmd) | |
1228 | ret = ops->cmd(lum->handle, lum->cmd, | |
1229 | (unsigned long) &lum->u, | |
1230 | &args, sock_info); | |
1231 | else | |
1232 | ret = -ENOSYS; | |
d61ad9ef MD |
1233 | if (args.counter_shm.shm_fd >= 0) { |
1234 | int close_ret; | |
1235 | ||
1236 | lttng_ust_lock_fd_tracker(); | |
1237 | close_ret = close(args.counter_shm.shm_fd); | |
1238 | lttng_ust_unlock_fd_tracker(); | |
1239 | args.counter_shm.shm_fd = -1; | |
1240 | if (close_ret) | |
1241 | PERROR("close"); | |
1242 | } | |
ebabbf58 MD |
1243 | break; |
1244 | } | |
fd17d7ce | 1245 | case LTTNG_UST_ABI_EVENT_NOTIFIER_CREATE: |
8406222c MD |
1246 | { |
1247 | /* Receive struct lttng_ust_event_notifier */ | |
fd17d7ce | 1248 | struct lttng_ust_abi_event_notifier event_notifier; |
8406222c MD |
1249 | |
1250 | if (sizeof(event_notifier) != lum->u.event_notifier.len) { | |
1251 | DBG("incorrect event notifier data message size: %u", lum->u.event_notifier.len); | |
1252 | ret = -EINVAL; | |
1253 | goto error; | |
1254 | } | |
1255 | len = ustcomm_recv_unix_sock(sock, &event_notifier, sizeof(event_notifier)); | |
1256 | switch (len) { | |
1257 | case 0: /* orderly shutdown */ | |
1258 | ret = 0; | |
1259 | goto error; | |
1260 | default: | |
1261 | if (len == sizeof(event_notifier)) { | |
1262 | DBG("event notifier data received"); | |
1263 | break; | |
1264 | } else if (len < 0) { | |
1265 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
1266 | if (len == -ECONNRESET) { | |
1267 | ERR("%s remote end closed connection", sock_info->name); | |
1268 | ret = len; | |
1269 | goto error; | |
1270 | } | |
1271 | ret = len; | |
1272 | goto error; | |
1273 | } else { | |
1274 | DBG("incorrect event notifier data message size: %zd", len); | |
1275 | ret = -EINVAL; | |
1276 | goto error; | |
1277 | } | |
1278 | } | |
1279 | if (ops->cmd) | |
1280 | ret = ops->cmd(lum->handle, lum->cmd, | |
1281 | (unsigned long) &event_notifier, | |
1282 | &args, sock_info); | |
1283 | else | |
1284 | ret = -ENOSYS; | |
1285 | break; | |
1286 | } | |
ebabbf58 | 1287 | |
d9e99d10 | 1288 | default: |
46050b1a MD |
1289 | if (ops->cmd) |
1290 | ret = ops->cmd(lum->handle, lum->cmd, | |
ef9ff354 | 1291 | (unsigned long) &lum->u, |
f59ed768 | 1292 | &args, sock_info); |
46050b1a MD |
1293 | else |
1294 | ret = -ENOSYS; | |
1295 | break; | |
d9e99d10 | 1296 | } |
46050b1a | 1297 | |
46050b1a MD |
1298 | lur.handle = lum->handle; |
1299 | lur.cmd = lum->cmd; | |
1300 | lur.ret_val = ret; | |
1301 | if (ret >= 0) { | |
7bc53e94 | 1302 | lur.ret_code = LTTNG_UST_OK; |
46050b1a | 1303 | } else { |
7bc53e94 MD |
1304 | /* |
1305 | * Use -LTTNG_UST_ERR as wildcard for UST internal | |
1306 | * error that are not caused by the transport, except if | |
1307 | * we already have a more precise error message to | |
1308 | * report. | |
1309 | */ | |
64b2564e DG |
1310 | if (ret > -LTTNG_UST_ERR) { |
1311 | /* Translate code to UST error. */ | |
1312 | switch (ret) { | |
1313 | case -EEXIST: | |
1314 | lur.ret_code = -LTTNG_UST_ERR_EXIST; | |
1315 | break; | |
1316 | case -EINVAL: | |
1317 | lur.ret_code = -LTTNG_UST_ERR_INVAL; | |
1318 | break; | |
1319 | case -ENOENT: | |
1320 | lur.ret_code = -LTTNG_UST_ERR_NOENT; | |
1321 | break; | |
1322 | case -EPERM: | |
1323 | lur.ret_code = -LTTNG_UST_ERR_PERM; | |
1324 | break; | |
1325 | case -ENOSYS: | |
1326 | lur.ret_code = -LTTNG_UST_ERR_NOSYS; | |
1327 | break; | |
1328 | default: | |
1329 | lur.ret_code = -LTTNG_UST_ERR; | |
1330 | break; | |
1331 | } | |
1332 | } else { | |
7bc53e94 | 1333 | lur.ret_code = ret; |
64b2564e | 1334 | } |
46050b1a | 1335 | } |
e6ea14c5 MD |
1336 | if (ret >= 0) { |
1337 | switch (lum->cmd) { | |
fd17d7ce | 1338 | case LTTNG_UST_ABI_TRACER_VERSION: |
e6ea14c5 MD |
1339 | lur.u.version = lum->u.version; |
1340 | break; | |
fd17d7ce | 1341 | case LTTNG_UST_ABI_TRACEPOINT_LIST_GET: |
e6ea14c5 MD |
1342 | memcpy(&lur.u.tracepoint, &lum->u.tracepoint, sizeof(lur.u.tracepoint)); |
1343 | break; | |
1344 | } | |
381c0f1e | 1345 | } |
74d81a6c | 1346 | DBG("Return value: %d", lur.ret_val); |
4c62d8d1 MD |
1347 | |
1348 | ust_unlock(); | |
1349 | ||
1350 | /* | |
1351 | * Performed delayed statedump operations outside of the UST | |
1352 | * lock. We need to take the dynamic loader lock before we take | |
1353 | * the UST lock internally within handle_pending_statedump(). | |
1354 | */ | |
1355 | handle_pending_statedump(sock_info); | |
1356 | ||
1357 | if (ust_lock()) { | |
1358 | ret = -LTTNG_UST_ERR_EXITING; | |
1359 | goto error; | |
1360 | } | |
1361 | ||
46050b1a | 1362 | ret = send_reply(sock, &lur); |
193183fb | 1363 | if (ret < 0) { |
7bc53e94 | 1364 | DBG("error sending reply"); |
193183fb MD |
1365 | goto error; |
1366 | } | |
46050b1a | 1367 | |
40003310 MD |
1368 | /* |
1369 | * LTTNG_UST_TRACEPOINT_FIELD_LIST_GET needs to send the field | |
1370 | * after the reply. | |
1371 | */ | |
7bc53e94 | 1372 | if (lur.ret_code == LTTNG_UST_OK) { |
40003310 | 1373 | switch (lum->cmd) { |
fd17d7ce | 1374 | case LTTNG_UST_ABI_TRACEPOINT_FIELD_LIST_GET: |
40003310 MD |
1375 | len = ustcomm_send_unix_sock(sock, |
1376 | &args.field_list.entry, | |
1377 | sizeof(args.field_list.entry)); | |
7bc53e94 MD |
1378 | if (len < 0) { |
1379 | ret = len; | |
1380 | goto error; | |
1381 | } | |
40003310 | 1382 | if (len != sizeof(args.field_list.entry)) { |
7bc53e94 | 1383 | ret = -EINVAL; |
40003310 MD |
1384 | goto error; |
1385 | } | |
1386 | } | |
1387 | } | |
ef9ff354 | 1388 | |
381c0f1e | 1389 | error: |
17dfb34b | 1390 | ust_unlock(); |
d9e99d10 | 1391 | |
37dddb65 | 1392 | return ret; |
246be17e PW |
1393 | } |
1394 | ||
46050b1a | 1395 | static |
efe0de09 | 1396 | void cleanup_sock_info(struct sock_info *sock_info, int exiting) |
46050b1a MD |
1397 | { |
1398 | int ret; | |
1399 | ||
5b14aab3 | 1400 | if (sock_info->root_handle != -1) { |
fd17d7ce | 1401 | ret = lttng_ust_abi_objd_unref(sock_info->root_handle, 1); |
5b14aab3 MD |
1402 | if (ret) { |
1403 | ERR("Error unref root handle"); | |
1404 | } | |
1405 | sock_info->root_handle = -1; | |
1406 | } | |
eb0e6022 GAPG |
1407 | sock_info->registration_done = 0; |
1408 | sock_info->initial_statedump_done = 0; | |
5b14aab3 MD |
1409 | |
1410 | /* | |
1411 | * wait_shm_mmap, socket and notify socket are used by listener | |
1412 | * threads outside of the ust lock, so we cannot tear them down | |
1413 | * ourselves, because we cannot join on these threads. Leave | |
1414 | * responsibility of cleaning up these resources to the OS | |
1415 | * process exit. | |
1416 | */ | |
1417 | if (exiting) | |
1418 | return; | |
1419 | ||
46050b1a | 1420 | if (sock_info->socket != -1) { |
e6973a89 | 1421 | ret = ustcomm_close_unix_sock(sock_info->socket); |
46050b1a | 1422 | if (ret) { |
32ce8569 | 1423 | ERR("Error closing ust cmd socket"); |
46050b1a MD |
1424 | } |
1425 | sock_info->socket = -1; | |
1426 | } | |
32ce8569 MD |
1427 | if (sock_info->notify_socket != -1) { |
1428 | ret = ustcomm_close_unix_sock(sock_info->notify_socket); | |
1429 | if (ret) { | |
1430 | ERR("Error closing ust notify socket"); | |
1431 | } | |
1432 | sock_info->notify_socket = -1; | |
1433 | } | |
5b14aab3 | 1434 | if (sock_info->wait_shm_mmap) { |
172d6b68 MD |
1435 | long page_size; |
1436 | ||
b72687b8 | 1437 | page_size = LTTNG_UST_PAGE_SIZE; |
2657d1ba MD |
1438 | if (page_size <= 0) { |
1439 | if (!page_size) { | |
1440 | errno = EINVAL; | |
1441 | } | |
1442 | PERROR("Error in sysconf(_SC_PAGE_SIZE)"); | |
1443 | } else { | |
172d6b68 MD |
1444 | ret = munmap(sock_info->wait_shm_mmap, page_size); |
1445 | if (ret) { | |
1446 | ERR("Error unmapping wait shm"); | |
1447 | } | |
7fc90dca MD |
1448 | } |
1449 | sock_info->wait_shm_mmap = NULL; | |
1450 | } | |
1451 | } | |
1452 | ||
58d4b2a2 | 1453 | /* |
33bbeb90 MD |
1454 | * Using fork to set umask in the child process (not multi-thread safe). |
1455 | * We deal with the shm_open vs ftruncate race (happening when the | |
1456 | * sessiond owns the shm and does not let everybody modify it, to ensure | |
1457 | * safety against shm_unlink) by simply letting the mmap fail and | |
1458 | * retrying after a few seconds. | |
1459 | * For global shm, everybody has rw access to it until the sessiond | |
1460 | * starts. | |
58d4b2a2 | 1461 | */ |
7fc90dca | 1462 | static |
58d4b2a2 | 1463 | int get_wait_shm(struct sock_info *sock_info, size_t mmap_size) |
7fc90dca | 1464 | { |
7fc90dca | 1465 | int wait_shm_fd, ret; |
58d4b2a2 | 1466 | pid_t pid; |
44e073f5 | 1467 | |
58d4b2a2 | 1468 | /* |
33bbeb90 | 1469 | * Try to open read-only. |
58d4b2a2 | 1470 | */ |
33bbeb90 | 1471 | wait_shm_fd = shm_open(sock_info->wait_shm_path, O_RDONLY, 0); |
58d4b2a2 | 1472 | if (wait_shm_fd >= 0) { |
7aa76730 MD |
1473 | int32_t tmp_read; |
1474 | ssize_t len; | |
1475 | size_t bytes_read = 0; | |
1476 | ||
1477 | /* | |
1478 | * Try to read the fd. If unable to do so, try opening | |
1479 | * it in write mode. | |
1480 | */ | |
1481 | do { | |
1482 | len = read(wait_shm_fd, | |
1483 | &((char *) &tmp_read)[bytes_read], | |
1484 | sizeof(tmp_read) - bytes_read); | |
1485 | if (len > 0) { | |
1486 | bytes_read += len; | |
1487 | } | |
1488 | } while ((len < 0 && errno == EINTR) | |
1489 | || (len > 0 && bytes_read < sizeof(tmp_read))); | |
1490 | if (bytes_read != sizeof(tmp_read)) { | |
1491 | ret = close(wait_shm_fd); | |
1492 | if (ret) { | |
1493 | ERR("close wait_shm_fd"); | |
1494 | } | |
1495 | goto open_write; | |
1496 | } | |
58d4b2a2 MD |
1497 | goto end; |
1498 | } else if (wait_shm_fd < 0 && errno != ENOENT) { | |
1499 | /* | |
33bbeb90 MD |
1500 | * Real-only open did not work, and it's not because the |
1501 | * entry was not present. It's a failure that prohibits | |
1502 | * using shm. | |
58d4b2a2 | 1503 | */ |
7fc90dca | 1504 | ERR("Error opening shm %s", sock_info->wait_shm_path); |
58d4b2a2 | 1505 | goto end; |
7fc90dca | 1506 | } |
7aa76730 MD |
1507 | |
1508 | open_write: | |
7fc90dca | 1509 | /* |
7aa76730 MD |
1510 | * If the open failed because the file did not exist, or because |
1511 | * the file was not truncated yet, try creating it ourself. | |
7fc90dca | 1512 | */ |
8c90a710 | 1513 | URCU_TLS(lttng_ust_nest_count)++; |
58d4b2a2 | 1514 | pid = fork(); |
8c90a710 | 1515 | URCU_TLS(lttng_ust_nest_count)--; |
58d4b2a2 MD |
1516 | if (pid > 0) { |
1517 | int status; | |
1518 | ||
1519 | /* | |
1520 | * Parent: wait for child to return, in which case the | |
1521 | * shared memory map will have been created. | |
1522 | */ | |
1523 | pid = wait(&status); | |
b7d3cb32 | 1524 | if (pid < 0 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) { |
58d4b2a2 MD |
1525 | wait_shm_fd = -1; |
1526 | goto end; | |
7fc90dca | 1527 | } |
58d4b2a2 MD |
1528 | /* |
1529 | * Try to open read-only again after creation. | |
1530 | */ | |
33bbeb90 | 1531 | wait_shm_fd = shm_open(sock_info->wait_shm_path, O_RDONLY, 0); |
58d4b2a2 MD |
1532 | if (wait_shm_fd < 0) { |
1533 | /* | |
1534 | * Real-only open did not work. It's a failure | |
1535 | * that prohibits using shm. | |
1536 | */ | |
1537 | ERR("Error opening shm %s", sock_info->wait_shm_path); | |
1538 | goto end; | |
1539 | } | |
1540 | goto end; | |
1541 | } else if (pid == 0) { | |
1542 | int create_mode; | |
1543 | ||
1544 | /* Child */ | |
33bbeb90 | 1545 | create_mode = S_IRUSR | S_IWUSR | S_IRGRP; |
58d4b2a2 | 1546 | if (sock_info->global) |
33bbeb90 | 1547 | create_mode |= S_IROTH | S_IWGRP | S_IWOTH; |
58d4b2a2 MD |
1548 | /* |
1549 | * We're alone in a child process, so we can modify the | |
1550 | * process-wide umask. | |
1551 | */ | |
33bbeb90 | 1552 | umask(~create_mode); |
58d4b2a2 | 1553 | /* |
33bbeb90 MD |
1554 | * Try creating shm (or get rw access). |
1555 | * We don't do an exclusive open, because we allow other | |
1556 | * processes to create+ftruncate it concurrently. | |
58d4b2a2 MD |
1557 | */ |
1558 | wait_shm_fd = shm_open(sock_info->wait_shm_path, | |
1559 | O_RDWR | O_CREAT, create_mode); | |
1560 | if (wait_shm_fd >= 0) { | |
1561 | ret = ftruncate(wait_shm_fd, mmap_size); | |
1562 | if (ret) { | |
1563 | PERROR("ftruncate"); | |
b0c1425d | 1564 | _exit(EXIT_FAILURE); |
58d4b2a2 | 1565 | } |
b0c1425d | 1566 | _exit(EXIT_SUCCESS); |
58d4b2a2 | 1567 | } |
33bbeb90 MD |
1568 | /* |
1569 | * For local shm, we need to have rw access to accept | |
1570 | * opening it: this means the local sessiond will be | |
1571 | * able to wake us up. For global shm, we open it even | |
1572 | * if rw access is not granted, because the root.root | |
1573 | * sessiond will be able to override all rights and wake | |
1574 | * us up. | |
1575 | */ | |
1576 | if (!sock_info->global && errno != EACCES) { | |
58d4b2a2 | 1577 | ERR("Error opening shm %s", sock_info->wait_shm_path); |
5d3bc5ed | 1578 | _exit(EXIT_FAILURE); |
58d4b2a2 MD |
1579 | } |
1580 | /* | |
33bbeb90 MD |
1581 | * The shm exists, but we cannot open it RW. Report |
1582 | * success. | |
58d4b2a2 | 1583 | */ |
5d3bc5ed | 1584 | _exit(EXIT_SUCCESS); |
58d4b2a2 MD |
1585 | } else { |
1586 | return -1; | |
7fc90dca | 1587 | } |
58d4b2a2 | 1588 | end: |
33bbeb90 MD |
1589 | if (wait_shm_fd >= 0 && !sock_info->global) { |
1590 | struct stat statbuf; | |
1591 | ||
1592 | /* | |
1593 | * Ensure that our user is the owner of the shm file for | |
1594 | * local shm. If we do not own the file, it means our | |
1595 | * sessiond will not have access to wake us up (there is | |
1596 | * probably a rogue process trying to fake our | |
1597 | * sessiond). Fallback to polling method in this case. | |
1598 | */ | |
1599 | ret = fstat(wait_shm_fd, &statbuf); | |
1600 | if (ret) { | |
1601 | PERROR("fstat"); | |
1602 | goto error_close; | |
1603 | } | |
1604 | if (statbuf.st_uid != getuid()) | |
1605 | goto error_close; | |
1606 | } | |
58d4b2a2 | 1607 | return wait_shm_fd; |
33bbeb90 MD |
1608 | |
1609 | error_close: | |
1610 | ret = close(wait_shm_fd); | |
1611 | if (ret) { | |
1612 | PERROR("Error closing fd"); | |
1613 | } | |
1614 | return -1; | |
58d4b2a2 MD |
1615 | } |
1616 | ||
1617 | static | |
1618 | char *get_map_shm(struct sock_info *sock_info) | |
1619 | { | |
172d6b68 | 1620 | long page_size; |
58d4b2a2 MD |
1621 | int wait_shm_fd, ret; |
1622 | char *wait_shm_mmap; | |
1623 | ||
172d6b68 | 1624 | page_size = sysconf(_SC_PAGE_SIZE); |
2657d1ba MD |
1625 | if (page_size <= 0) { |
1626 | if (!page_size) { | |
1627 | errno = EINVAL; | |
1628 | } | |
1629 | PERROR("Error in sysconf(_SC_PAGE_SIZE)"); | |
172d6b68 MD |
1630 | goto error; |
1631 | } | |
1632 | ||
6548fca4 | 1633 | lttng_ust_lock_fd_tracker(); |
172d6b68 | 1634 | wait_shm_fd = get_wait_shm(sock_info, page_size); |
58d4b2a2 | 1635 | if (wait_shm_fd < 0) { |
6548fca4 | 1636 | lttng_ust_unlock_fd_tracker(); |
58d4b2a2 | 1637 | goto error; |
44e073f5 | 1638 | } |
f5c453e9 JR |
1639 | |
1640 | ret = lttng_ust_add_fd_to_tracker(wait_shm_fd); | |
1641 | if (ret < 0) { | |
1642 | ret = close(wait_shm_fd); | |
1643 | if (!ret) { | |
1644 | PERROR("Error closing fd"); | |
1645 | } | |
1646 | lttng_ust_unlock_fd_tracker(); | |
1647 | goto error; | |
1648 | } | |
1649 | ||
1650 | wait_shm_fd = ret; | |
6548fca4 MD |
1651 | lttng_ust_unlock_fd_tracker(); |
1652 | ||
172d6b68 | 1653 | wait_shm_mmap = mmap(NULL, page_size, PROT_READ, |
7fc90dca | 1654 | MAP_SHARED, wait_shm_fd, 0); |
6548fca4 | 1655 | |
7fc90dca | 1656 | /* close shm fd immediately after taking the mmap reference */ |
6548fca4 | 1657 | lttng_ust_lock_fd_tracker(); |
7fc90dca | 1658 | ret = close(wait_shm_fd); |
6548fca4 MD |
1659 | if (!ret) { |
1660 | lttng_ust_delete_fd_from_tracker(wait_shm_fd); | |
1661 | } else { | |
33bbeb90 MD |
1662 | PERROR("Error closing fd"); |
1663 | } | |
6548fca4 MD |
1664 | lttng_ust_unlock_fd_tracker(); |
1665 | ||
33bbeb90 MD |
1666 | if (wait_shm_mmap == MAP_FAILED) { |
1667 | DBG("mmap error (can be caused by race with sessiond). Fallback to poll mode."); | |
1668 | goto error; | |
7fc90dca MD |
1669 | } |
1670 | return wait_shm_mmap; | |
1671 | ||
1672 | error: | |
1673 | return NULL; | |
1674 | } | |
1675 | ||
1676 | static | |
1677 | void wait_for_sessiond(struct sock_info *sock_info) | |
1678 | { | |
060577e3 | 1679 | /* Use ust_lock to check if we should quit. */ |
3327ac33 | 1680 | if (ust_lock()) { |
7fc90dca MD |
1681 | goto quit; |
1682 | } | |
37ed587a MD |
1683 | if (wait_poll_fallback) { |
1684 | goto error; | |
1685 | } | |
7fc90dca MD |
1686 | ust_unlock(); |
1687 | ||
060577e3 JR |
1688 | assert(sock_info->wait_shm_mmap); |
1689 | ||
7fc90dca | 1690 | DBG("Waiting for %s apps sessiond", sock_info->name); |
80e2814b | 1691 | /* Wait for futex wakeup */ |
ee7fcec8 MD |
1692 | if (uatomic_read((int32_t *) sock_info->wait_shm_mmap)) |
1693 | goto end_wait; | |
1694 | ||
10544ee8 | 1695 | while (lttng_ust_futex_async((int32_t *) sock_info->wait_shm_mmap, |
ee7fcec8 MD |
1696 | FUTEX_WAIT, 0, NULL, NULL, 0)) { |
1697 | switch (errno) { | |
1698 | case EWOULDBLOCK: | |
1699 | /* Value already changed. */ | |
1700 | goto end_wait; | |
1701 | case EINTR: | |
1702 | /* Retry if interrupted by signal. */ | |
1703 | break; /* Get out of switch. */ | |
1704 | case EFAULT: | |
1705 | wait_poll_fallback = 1; | |
1706 | DBG( | |
37ed587a MD |
1707 | "Linux kernels 2.6.33 to 3.0 (with the exception of stable versions) " |
1708 | "do not support FUTEX_WAKE on read-only memory mappings correctly. " | |
1709 | "Please upgrade your kernel " | |
1710 | "(fix is commit 9ea71503a8ed9184d2d0b8ccc4d269d05f7940ae in Linux kernel " | |
1711 | "mainline). LTTng-UST will use polling mode fallback."); | |
c6e6343c | 1712 | if (lttng_ust_logging_debug_enabled()) |
ee7fcec8 MD |
1713 | PERROR("futex"); |
1714 | goto end_wait; | |
80e2814b MD |
1715 | } |
1716 | } | |
ee7fcec8 | 1717 | end_wait: |
7fc90dca MD |
1718 | return; |
1719 | ||
1720 | quit: | |
1721 | ust_unlock(); | |
1722 | return; | |
1723 | ||
1724 | error: | |
1725 | ust_unlock(); | |
7fc90dca | 1726 | return; |
46050b1a MD |
1727 | } |
1728 | ||
1ea11eab MD |
1729 | /* |
1730 | * This thread does not allocate any resource, except within | |
1731 | * handle_message, within mutex protection. This mutex protects against | |
1732 | * fork and exit. | |
98bf993f | 1733 | * The other moment it allocates resources is at socket connection, which |
1ea11eab MD |
1734 | * is also protected by the mutex. |
1735 | */ | |
d9e99d10 MD |
1736 | static |
1737 | void *ust_listener_thread(void *arg) | |
1738 | { | |
1ea11eab | 1739 | struct sock_info *sock_info = arg; |
f5c453e9 | 1740 | int sock, ret, prev_connect_failed = 0, has_waited = 0, fd; |
ff517991 | 1741 | long timeout; |
d9e99d10 | 1742 | |
a9fd951a | 1743 | lttng_ust_alloc_tls(); |
01f0e40c RB |
1744 | /* |
1745 | * If available, add '-ust' to the end of this thread's | |
1746 | * process name | |
1747 | */ | |
1748 | ret = lttng_ust_setustprocname(); | |
1749 | if (ret) { | |
1750 | ERR("Unable to set UST process name"); | |
1751 | } | |
1752 | ||
9eb62b9c MD |
1753 | /* Restart trying to connect to the session daemon */ |
1754 | restart: | |
c0eedf81 MD |
1755 | if (prev_connect_failed) { |
1756 | /* Wait for sessiond availability with pipe */ | |
1757 | wait_for_sessiond(sock_info); | |
1758 | if (has_waited) { | |
1759 | has_waited = 0; | |
1760 | /* | |
1761 | * Sleep for 5 seconds before retrying after a | |
1762 | * sequence of failure / wait / failure. This | |
1763 | * deals with a killed or broken session daemon. | |
1764 | */ | |
1765 | sleep(5); | |
eacc4aa4 MD |
1766 | } else { |
1767 | has_waited = 1; | |
c0eedf81 | 1768 | } |
c0eedf81 MD |
1769 | prev_connect_failed = 0; |
1770 | } | |
9eb62b9c | 1771 | |
101dace0 JR |
1772 | if (ust_lock()) { |
1773 | goto quit; | |
1774 | } | |
1775 | ||
1ea11eab | 1776 | if (sock_info->socket != -1) { |
6548fca4 | 1777 | /* FD tracker is updated by ustcomm_close_unix_sock() */ |
e6973a89 | 1778 | ret = ustcomm_close_unix_sock(sock_info->socket); |
1ea11eab | 1779 | if (ret) { |
32ce8569 MD |
1780 | ERR("Error closing %s ust cmd socket", |
1781 | sock_info->name); | |
1ea11eab MD |
1782 | } |
1783 | sock_info->socket = -1; | |
1784 | } | |
32ce8569 | 1785 | if (sock_info->notify_socket != -1) { |
6548fca4 | 1786 | /* FD tracker is updated by ustcomm_close_unix_sock() */ |
32ce8569 MD |
1787 | ret = ustcomm_close_unix_sock(sock_info->notify_socket); |
1788 | if (ret) { | |
1789 | ERR("Error closing %s ust notify socket", | |
1790 | sock_info->name); | |
1791 | } | |
1792 | sock_info->notify_socket = -1; | |
1793 | } | |
46050b1a | 1794 | |
6548fca4 | 1795 | |
321f2351 MD |
1796 | /* |
1797 | * Register. We need to perform both connect and sending | |
1798 | * registration message before doing the next connect otherwise | |
1799 | * we may reach unix socket connect queue max limits and block | |
1800 | * on the 2nd connect while the session daemon is awaiting the | |
1801 | * first connect registration message. | |
1802 | */ | |
1803 | /* Connect cmd socket */ | |
6548fca4 | 1804 | lttng_ust_lock_fd_tracker(); |
451d66b2 MD |
1805 | ret = ustcomm_connect_unix_sock(sock_info->sock_path, |
1806 | get_connect_sock_timeout()); | |
321f2351 | 1807 | if (ret < 0) { |
6548fca4 | 1808 | lttng_ust_unlock_fd_tracker(); |
321f2351 MD |
1809 | DBG("Info: sessiond not accepting connections to %s apps socket", sock_info->name); |
1810 | prev_connect_failed = 1; | |
5b14aab3 | 1811 | |
e3426ddc | 1812 | /* |
321f2351 MD |
1813 | * If we cannot find the sessiond daemon, don't delay |
1814 | * constructor execution. | |
e3426ddc | 1815 | */ |
eb0e6022 | 1816 | ret = handle_register_failed(sock_info); |
321f2351 MD |
1817 | assert(!ret); |
1818 | ust_unlock(); | |
1819 | goto restart; | |
27fe9f21 | 1820 | } |
f5c453e9 JR |
1821 | fd = ret; |
1822 | ret = lttng_ust_add_fd_to_tracker(fd); | |
1823 | if (ret < 0) { | |
1824 | ret = close(fd); | |
1825 | if (ret) { | |
1826 | PERROR("close on sock_info->socket"); | |
1827 | } | |
1828 | ret = -1; | |
1829 | lttng_ust_unlock_fd_tracker(); | |
1830 | ust_unlock(); | |
1831 | goto quit; | |
1832 | } | |
1833 | ||
321f2351 | 1834 | sock_info->socket = ret; |
f5c453e9 | 1835 | lttng_ust_unlock_fd_tracker(); |
27fe9f21 | 1836 | |
6548fca4 MD |
1837 | ust_unlock(); |
1838 | /* | |
1839 | * Unlock/relock ust lock because connect is blocking (with | |
1840 | * timeout). Don't delay constructors on the ust lock for too | |
1841 | * long. | |
1842 | */ | |
3327ac33 | 1843 | if (ust_lock()) { |
5b14aab3 MD |
1844 | goto quit; |
1845 | } | |
1846 | ||
46050b1a MD |
1847 | /* |
1848 | * Create only one root handle per listener thread for the whole | |
f59ed768 MD |
1849 | * process lifetime, so we ensure we get ID which is statically |
1850 | * assigned to the root handle. | |
46050b1a MD |
1851 | */ |
1852 | if (sock_info->root_handle == -1) { | |
1853 | ret = lttng_abi_create_root_handle(); | |
a51070bb | 1854 | if (ret < 0) { |
46050b1a | 1855 | ERR("Error creating root handle"); |
46050b1a MD |
1856 | goto quit; |
1857 | } | |
1858 | sock_info->root_handle = ret; | |
9eb62b9c | 1859 | } |
1ea11eab | 1860 | |
249cffb5 | 1861 | ret = register_to_sessiond(sock_info->socket, LTTNG_UST_CTL_SOCKET_CMD); |
9eb62b9c | 1862 | if (ret < 0) { |
32ce8569 MD |
1863 | ERR("Error registering to %s ust cmd socket", |
1864 | sock_info->name); | |
c0eedf81 | 1865 | prev_connect_failed = 1; |
11ff9c7d MD |
1866 | /* |
1867 | * If we cannot register to the sessiond daemon, don't | |
1868 | * delay constructor execution. | |
1869 | */ | |
eb0e6022 | 1870 | ret = handle_register_failed(sock_info); |
11ff9c7d | 1871 | assert(!ret); |
17dfb34b | 1872 | ust_unlock(); |
9eb62b9c MD |
1873 | goto restart; |
1874 | } | |
321f2351 MD |
1875 | |
1876 | ust_unlock(); | |
6548fca4 MD |
1877 | /* |
1878 | * Unlock/relock ust lock because connect is blocking (with | |
1879 | * timeout). Don't delay constructors on the ust lock for too | |
1880 | * long. | |
1881 | */ | |
1882 | if (ust_lock()) { | |
1883 | goto quit; | |
1884 | } | |
321f2351 MD |
1885 | |
1886 | /* Connect notify socket */ | |
6548fca4 | 1887 | lttng_ust_lock_fd_tracker(); |
451d66b2 MD |
1888 | ret = ustcomm_connect_unix_sock(sock_info->sock_path, |
1889 | get_connect_sock_timeout()); | |
321f2351 | 1890 | if (ret < 0) { |
6548fca4 | 1891 | lttng_ust_unlock_fd_tracker(); |
321f2351 MD |
1892 | DBG("Info: sessiond not accepting connections to %s apps socket", sock_info->name); |
1893 | prev_connect_failed = 1; | |
1894 | ||
321f2351 MD |
1895 | /* |
1896 | * If we cannot find the sessiond daemon, don't delay | |
1897 | * constructor execution. | |
1898 | */ | |
eb0e6022 | 1899 | ret = handle_register_failed(sock_info); |
321f2351 MD |
1900 | assert(!ret); |
1901 | ust_unlock(); | |
1902 | goto restart; | |
1903 | } | |
f5c453e9 JR |
1904 | |
1905 | fd = ret; | |
1906 | ret = lttng_ust_add_fd_to_tracker(fd); | |
1907 | if (ret < 0) { | |
1908 | ret = close(fd); | |
1909 | if (ret) { | |
1910 | PERROR("close on sock_info->notify_socket"); | |
1911 | } | |
1912 | ret = -1; | |
1913 | lttng_ust_unlock_fd_tracker(); | |
1914 | ust_unlock(); | |
1915 | goto quit; | |
1916 | } | |
1917 | ||
321f2351 | 1918 | sock_info->notify_socket = ret; |
f5c453e9 | 1919 | lttng_ust_unlock_fd_tracker(); |
321f2351 | 1920 | |
6548fca4 MD |
1921 | ust_unlock(); |
1922 | /* | |
1923 | * Unlock/relock ust lock because connect is blocking (with | |
1924 | * timeout). Don't delay constructors on the ust lock for too | |
1925 | * long. | |
1926 | */ | |
1927 | if (ust_lock()) { | |
1928 | goto quit; | |
1929 | } | |
1930 | ||
321f2351 MD |
1931 | timeout = get_notify_sock_timeout(); |
1932 | if (timeout >= 0) { | |
1933 | /* | |
1934 | * Give at least 10ms to sessiond to reply to | |
1935 | * notifications. | |
1936 | */ | |
1937 | if (timeout < 10) | |
1938 | timeout = 10; | |
1939 | ret = ustcomm_setsockopt_rcv_timeout(sock_info->notify_socket, | |
1940 | timeout); | |
1941 | if (ret < 0) { | |
1942 | WARN("Error setting socket receive timeout"); | |
1943 | } | |
1944 | ret = ustcomm_setsockopt_snd_timeout(sock_info->notify_socket, | |
1945 | timeout); | |
1946 | if (ret < 0) { | |
1947 | WARN("Error setting socket send timeout"); | |
1948 | } | |
1949 | } else if (timeout < -1) { | |
1950 | WARN("Unsupported timeout value %ld", timeout); | |
1951 | } | |
1952 | ||
32ce8569 | 1953 | ret = register_to_sessiond(sock_info->notify_socket, |
249cffb5 | 1954 | LTTNG_UST_CTL_SOCKET_NOTIFY); |
32ce8569 MD |
1955 | if (ret < 0) { |
1956 | ERR("Error registering to %s ust notify socket", | |
1957 | sock_info->name); | |
1958 | prev_connect_failed = 1; | |
1959 | /* | |
1960 | * If we cannot register to the sessiond daemon, don't | |
1961 | * delay constructor execution. | |
1962 | */ | |
eb0e6022 | 1963 | ret = handle_register_failed(sock_info); |
32ce8569 MD |
1964 | assert(!ret); |
1965 | ust_unlock(); | |
1966 | goto restart; | |
1967 | } | |
1968 | sock = sock_info->socket; | |
1969 | ||
17dfb34b | 1970 | ust_unlock(); |
46050b1a | 1971 | |
d9e99d10 MD |
1972 | for (;;) { |
1973 | ssize_t len; | |
57773204 | 1974 | struct ustcomm_ust_msg lum; |
d9e99d10 | 1975 | |
57773204 | 1976 | len = ustcomm_recv_unix_sock(sock, &lum, sizeof(lum)); |
d9e99d10 MD |
1977 | switch (len) { |
1978 | case 0: /* orderly shutdown */ | |
7dd08bec | 1979 | DBG("%s lttng-sessiond has performed an orderly shutdown", sock_info->name); |
3327ac33 | 1980 | if (ust_lock()) { |
d5e1fea6 MD |
1981 | goto quit; |
1982 | } | |
8236ba10 MD |
1983 | /* |
1984 | * Either sessiond has shutdown or refused us by closing the socket. | |
1985 | * In either case, we don't want to delay construction execution, | |
1986 | * and we need to wait before retry. | |
1987 | */ | |
1988 | prev_connect_failed = 1; | |
1989 | /* | |
1990 | * If we cannot register to the sessiond daemon, don't | |
1991 | * delay constructor execution. | |
1992 | */ | |
eb0e6022 | 1993 | ret = handle_register_failed(sock_info); |
8236ba10 MD |
1994 | assert(!ret); |
1995 | ust_unlock(); | |
d9e99d10 | 1996 | goto end; |
e7723462 | 1997 | case sizeof(lum): |
74d81a6c | 1998 | print_cmd(lum.cmd, lum.handle); |
11ff9c7d | 1999 | ret = handle_message(sock_info, sock, &lum); |
7bc53e94 | 2000 | if (ret) { |
0dafcd63 MD |
2001 | ERR("Error handling message for %s socket", |
2002 | sock_info->name); | |
2003 | /* | |
2004 | * Close socket if protocol error is | |
2005 | * detected. | |
2006 | */ | |
2007 | goto end; | |
d9e99d10 MD |
2008 | } |
2009 | continue; | |
7bc53e94 MD |
2010 | default: |
2011 | if (len < 0) { | |
2012 | DBG("Receive failed from lttng-sessiond with errno %d", (int) -len); | |
2013 | } else { | |
2014 | DBG("incorrect message size (%s socket): %zd", sock_info->name, len); | |
2015 | } | |
2016 | if (len == -ECONNRESET) { | |
2017 | DBG("%s remote end closed connection", sock_info->name); | |
d9e99d10 MD |
2018 | goto end; |
2019 | } | |
2020 | goto end; | |
d9e99d10 MD |
2021 | } |
2022 | ||
2023 | } | |
2024 | end: | |
3327ac33 | 2025 | if (ust_lock()) { |
d5e1fea6 MD |
2026 | goto quit; |
2027 | } | |
f59ed768 | 2028 | /* Cleanup socket handles before trying to reconnect */ |
fd17d7ce | 2029 | lttng_ust_abi_objd_table_owner_cleanup(sock_info); |
f59ed768 | 2030 | ust_unlock(); |
9eb62b9c | 2031 | goto restart; /* try to reconnect */ |
e33f3265 | 2032 | |
1ea11eab | 2033 | quit: |
e33f3265 | 2034 | ust_unlock(); |
3327ac33 MD |
2035 | |
2036 | pthread_mutex_lock(&ust_exit_mutex); | |
2037 | sock_info->thread_active = 0; | |
2038 | pthread_mutex_unlock(&ust_exit_mutex); | |
d9e99d10 MD |
2039 | return NULL; |
2040 | } | |
2041 | ||
2594a5b4 MD |
2042 | /* |
2043 | * Weak symbol to call when the ust malloc wrapper is not loaded. | |
2044 | */ | |
2045 | __attribute__((weak)) | |
fca97dfd | 2046 | void lttng_ust_libc_wrapper_malloc_ctor(void) |
2594a5b4 MD |
2047 | { |
2048 | } | |
2049 | ||
2691221a MD |
2050 | /* |
2051 | * sessiond monitoring thread: monitor presence of global and per-user | |
2052 | * sessiond by polling the application common named pipe. | |
2053 | */ | |
465a0d04 | 2054 | static |
fca97dfd | 2055 | void lttng_ust_ctor(void) |
465a0d04 MJ |
2056 | __attribute__((constructor)); |
2057 | static | |
fca97dfd | 2058 | void lttng_ust_ctor(void) |
2691221a | 2059 | { |
11ff9c7d | 2060 | struct timespec constructor_timeout; |
ae6a58bf | 2061 | sigset_t sig_all_blocked, orig_parent_mask; |
1879f67f | 2062 | pthread_attr_t thread_attr; |
cf12a773 | 2063 | int timeout_mode; |
2691221a | 2064 | int ret; |
b2292d85 | 2065 | void *handle; |
2691221a | 2066 | |
edaa1431 MD |
2067 | if (uatomic_xchg(&initialized, 1) == 1) |
2068 | return; | |
2069 | ||
eddd8d5d | 2070 | /* |
a9fd951a | 2071 | * Fixup interdependency between TLS allocation mutex (which happens |
eddd8d5d MD |
2072 | * to be the dynamic linker mutex) and ust_lock, taken within |
2073 | * the ust lock. | |
2074 | */ | |
a9fd951a | 2075 | lttng_ust_alloc_tls(); |
eddd8d5d | 2076 | |
07b57e5e MD |
2077 | lttng_ust_loaded = 1; |
2078 | ||
b2292d85 FD |
2079 | /* |
2080 | * We need to ensure that the liblttng-ust library is not unloaded to avoid | |
2081 | * the unloading of code used by the ust_listener_threads as we can not | |
2082 | * reliably know when they exited. To do that, manually load | |
2083 | * liblttng-ust.so to increment the dynamic loader's internal refcount for | |
2084 | * this library so it never becomes zero, thus never gets unloaded from the | |
2085 | * address space of the process. Since we are already running in the | |
3d3dc207 | 2086 | * constructor of the LTTNG_UST_LIB_SONAME library, calling dlopen will |
b2292d85 FD |
2087 | * simply increment the refcount and no additionnal work is needed by the |
2088 | * dynamic loader as the shared library is already loaded in the address | |
2089 | * space. As a safe guard, we use the RTLD_NODELETE flag to prevent | |
2090 | * unloading of the UST library if its refcount becomes zero (which should | |
2091 | * never happen). Do the return value check but discard the handle at the | |
2092 | * end of the function as it's not needed. | |
2093 | */ | |
3d3dc207 | 2094 | handle = dlopen(LTTNG_UST_LIB_SONAME, RTLD_LAZY | RTLD_NODELETE); |
b2292d85 | 2095 | if (!handle) { |
3d3dc207 | 2096 | ERR("dlopen of liblttng-ust shared library (%s).", LTTNG_UST_LIB_SONAME); |
b2292d85 FD |
2097 | } |
2098 | ||
edaa1431 MD |
2099 | /* |
2100 | * We want precise control over the order in which we construct | |
2101 | * our sub-libraries vs starting to receive commands from | |
2102 | * sessiond (otherwise leading to errors when trying to create | |
2103 | * sessiond before the init functions are completed). | |
2104 | */ | |
39313bf3 MJ |
2105 | |
2106 | /* | |
2107 | * Both the logging and getenv lazy-initialization uses getenv() | |
2108 | * internally and thus needs to be explicitly initialized in | |
2109 | * liblttng-ust before we start any threads as an unsuspecting normally | |
2110 | * single threaded application using liblttng-ust could be using | |
2111 | * setenv() which is not thread-safe. | |
2112 | */ | |
c6e6343c | 2113 | lttng_ust_logging_init(); |
39313bf3 MJ |
2114 | lttng_ust_getenv_init(); |
2115 | ||
fca97dfd MJ |
2116 | /* Call the liblttng-ust-common constructor. */ |
2117 | lttng_ust_common_ctor(); | |
2118 | ||
25afb7ac | 2119 | lttng_ust_tp_init(); |
cf73e0fe | 2120 | lttng_ust_statedump_init(); |
14e0a135 MD |
2121 | lttng_ust_ring_buffer_clients_init(); |
2122 | lttng_ust_counter_clients_init(); | |
d58d1454 | 2123 | lttng_perf_counter_init(); |
2594a5b4 MD |
2124 | /* |
2125 | * Invoke ust malloc wrapper init before starting other threads. | |
2126 | */ | |
fca97dfd | 2127 | lttng_ust_libc_wrapper_malloc_ctor(); |
2691221a | 2128 | |
ff517991 | 2129 | timeout_mode = get_constructor_timeout(&constructor_timeout); |
11ff9c7d | 2130 | |
b2c5f61a | 2131 | get_allow_blocking(); |
6f97f9c2 | 2132 | |
95259bd0 | 2133 | ret = sem_init(&constructor_wait, 0, 0); |
8aadb54a MD |
2134 | if (ret) { |
2135 | PERROR("sem_init"); | |
2136 | } | |
11ff9c7d | 2137 | |
060577e3 JR |
2138 | ret = setup_global_apps(); |
2139 | if (ret) { | |
2140 | assert(global_apps.allowed == 0); | |
2141 | DBG("global apps setup returned %d", ret); | |
2142 | } | |
2143 | ||
8d20bf54 | 2144 | ret = setup_local_apps(); |
2691221a | 2145 | if (ret) { |
060577e3 | 2146 | assert(local_apps.allowed == 0); |
9ec6895c | 2147 | DBG("local apps setup returned %d", ret); |
2691221a | 2148 | } |
ae6a58bf WP |
2149 | |
2150 | /* A new thread created by pthread_create inherits the signal mask | |
2151 | * from the parent. To avoid any signal being received by the | |
2152 | * listener thread, we block all signals temporarily in the parent, | |
2153 | * while we create the listener thread. | |
2154 | */ | |
2155 | sigfillset(&sig_all_blocked); | |
2156 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_parent_mask); | |
2157 | if (ret) { | |
d94d802c | 2158 | ERR("pthread_sigmask: %s", strerror(ret)); |
ae6a58bf WP |
2159 | } |
2160 | ||
1879f67f MG |
2161 | ret = pthread_attr_init(&thread_attr); |
2162 | if (ret) { | |
2163 | ERR("pthread_attr_init: %s", strerror(ret)); | |
2164 | } | |
2165 | ret = pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED); | |
2166 | if (ret) { | |
2167 | ERR("pthread_attr_setdetachstate: %s", strerror(ret)); | |
2168 | } | |
2169 | ||
060577e3 JR |
2170 | if (global_apps.allowed) { |
2171 | pthread_mutex_lock(&ust_exit_mutex); | |
2172 | ret = pthread_create(&global_apps.ust_listener, &thread_attr, | |
2173 | ust_listener_thread, &global_apps); | |
2174 | if (ret) { | |
2175 | ERR("pthread_create global: %s", strerror(ret)); | |
2176 | } | |
2177 | global_apps.thread_active = 1; | |
2178 | pthread_mutex_unlock(&ust_exit_mutex); | |
2179 | } else { | |
2180 | handle_register_done(&global_apps); | |
d94d802c | 2181 | } |
e33f3265 | 2182 | |
8d20bf54 | 2183 | if (local_apps.allowed) { |
c0bbbd5a | 2184 | pthread_mutex_lock(&ust_exit_mutex); |
1879f67f | 2185 | ret = pthread_create(&local_apps.ust_listener, &thread_attr, |
dde70ea0 | 2186 | ust_listener_thread, &local_apps); |
d94d802c MD |
2187 | if (ret) { |
2188 | ERR("pthread_create local: %s", strerror(ret)); | |
2189 | } | |
e33f3265 | 2190 | local_apps.thread_active = 1; |
c0bbbd5a | 2191 | pthread_mutex_unlock(&ust_exit_mutex); |
8d20bf54 MD |
2192 | } else { |
2193 | handle_register_done(&local_apps); | |
2194 | } | |
1879f67f MG |
2195 | ret = pthread_attr_destroy(&thread_attr); |
2196 | if (ret) { | |
2197 | ERR("pthread_attr_destroy: %s", strerror(ret)); | |
2198 | } | |
8d20bf54 | 2199 | |
ae6a58bf WP |
2200 | /* Restore original signal mask in parent */ |
2201 | ret = pthread_sigmask(SIG_SETMASK, &orig_parent_mask, NULL); | |
2202 | if (ret) { | |
d94d802c | 2203 | ERR("pthread_sigmask: %s", strerror(ret)); |
ae6a58bf WP |
2204 | } |
2205 | ||
cf12a773 MD |
2206 | switch (timeout_mode) { |
2207 | case 1: /* timeout wait */ | |
95259bd0 MD |
2208 | do { |
2209 | ret = sem_timedwait(&constructor_wait, | |
2210 | &constructor_timeout); | |
2211 | } while (ret < 0 && errno == EINTR); | |
8aadb54a MD |
2212 | if (ret < 0) { |
2213 | switch (errno) { | |
2214 | case ETIMEDOUT: | |
2215 | ERR("Timed out waiting for lttng-sessiond"); | |
2216 | break; | |
2217 | case EINVAL: | |
2218 | PERROR("sem_timedwait"); | |
2219 | break; | |
2220 | default: | |
2221 | ERR("Unexpected error \"%s\" returned by sem_timedwait", | |
2222 | strerror(errno)); | |
2223 | } | |
cf12a773 MD |
2224 | } |
2225 | break; | |
7b766b16 | 2226 | case -1:/* wait forever */ |
95259bd0 MD |
2227 | do { |
2228 | ret = sem_wait(&constructor_wait); | |
2229 | } while (ret < 0 && errno == EINTR); | |
8aadb54a MD |
2230 | if (ret < 0) { |
2231 | switch (errno) { | |
2232 | case EINVAL: | |
2233 | PERROR("sem_wait"); | |
2234 | break; | |
2235 | default: | |
2236 | ERR("Unexpected error \"%s\" returned by sem_wait", | |
2237 | strerror(errno)); | |
2238 | } | |
2239 | } | |
cf12a773 | 2240 | break; |
7b766b16 | 2241 | case 0: /* no timeout */ |
cf12a773 | 2242 | break; |
11ff9c7d | 2243 | } |
2691221a MD |
2244 | } |
2245 | ||
17dfb34b MD |
2246 | static |
2247 | void lttng_ust_cleanup(int exiting) | |
2248 | { | |
efe0de09 | 2249 | cleanup_sock_info(&global_apps, exiting); |
932cfadb | 2250 | cleanup_sock_info(&local_apps, exiting); |
74f98bc9 | 2251 | local_apps.allowed = 0; |
060577e3 | 2252 | global_apps.allowed = 0; |
efe0de09 MD |
2253 | /* |
2254 | * The teardown in this function all affect data structures | |
2255 | * accessed under the UST lock by the listener thread. This | |
2256 | * lock, along with the lttng_ust_comm_should_quit flag, ensure | |
2257 | * that none of these threads are accessing this data at this | |
2258 | * point. | |
2259 | */ | |
17dfb34b | 2260 | lttng_ust_abi_exit(); |
fd17d7ce | 2261 | lttng_ust_abi_events_exit(); |
d58d1454 | 2262 | lttng_perf_counter_exit(); |
14e0a135 MD |
2263 | lttng_ust_ring_buffer_clients_exit(); |
2264 | lttng_ust_counter_clients_exit(); | |
cf73e0fe | 2265 | lttng_ust_statedump_destroy(); |
25afb7ac | 2266 | lttng_ust_tp_exit(); |
17dfb34b MD |
2267 | if (!exiting) { |
2268 | /* Reinitialize values for fork */ | |
eb0e6022 | 2269 | sem_count = sem_count_initial_value; |
17dfb34b MD |
2270 | lttng_ust_comm_should_quit = 0; |
2271 | initialized = 0; | |
2272 | } | |
2273 | } | |
2274 | ||
c589eca2 MJ |
2275 | static |
2276 | void lttng_ust_exit(void) | |
2277 | __attribute__((destructor)); | |
2278 | static | |
2279 | void lttng_ust_exit(void) | |
2691221a MD |
2280 | { |
2281 | int ret; | |
2282 | ||
9eb62b9c MD |
2283 | /* |
2284 | * Using pthread_cancel here because: | |
2285 | * A) we don't want to hang application teardown. | |
2286 | * B) the thread is not allocating any resource. | |
2287 | */ | |
1ea11eab MD |
2288 | |
2289 | /* | |
2290 | * Require the communication thread to quit. Synchronize with | |
2291 | * mutexes to ensure it is not in a mutex critical section when | |
2292 | * pthread_cancel is later called. | |
2293 | */ | |
3327ac33 | 2294 | ust_lock_nocheck(); |
1ea11eab | 2295 | lttng_ust_comm_should_quit = 1; |
3327ac33 | 2296 | ust_unlock(); |
1ea11eab | 2297 | |
3327ac33 | 2298 | pthread_mutex_lock(&ust_exit_mutex); |
f5f94532 | 2299 | /* cancel threads */ |
e33f3265 MD |
2300 | if (global_apps.thread_active) { |
2301 | ret = pthread_cancel(global_apps.ust_listener); | |
2302 | if (ret) { | |
2303 | ERR("Error cancelling global ust listener thread: %s", | |
2304 | strerror(ret)); | |
2305 | } else { | |
2306 | global_apps.thread_active = 0; | |
2307 | } | |
2691221a | 2308 | } |
e33f3265 | 2309 | if (local_apps.thread_active) { |
8d20bf54 MD |
2310 | ret = pthread_cancel(local_apps.ust_listener); |
2311 | if (ret) { | |
d94d802c MD |
2312 | ERR("Error cancelling local ust listener thread: %s", |
2313 | strerror(ret)); | |
e33f3265 MD |
2314 | } else { |
2315 | local_apps.thread_active = 0; | |
8d20bf54 | 2316 | } |
8d20bf54 | 2317 | } |
3327ac33 | 2318 | pthread_mutex_unlock(&ust_exit_mutex); |
e33f3265 | 2319 | |
efe0de09 MD |
2320 | /* |
2321 | * Do NOT join threads: use of sys_futex makes it impossible to | |
2322 | * join the threads without using async-cancel, but async-cancel | |
2323 | * is delivered by a signal, which could hit the target thread | |
2324 | * anywhere in its code path, including while the ust_lock() is | |
2325 | * held, causing a deadlock for the other thread. Let the OS | |
2326 | * cleanup the threads if there are stalled in a syscall. | |
2327 | */ | |
17dfb34b | 2328 | lttng_ust_cleanup(1); |
2691221a | 2329 | } |
e822f505 | 2330 | |
735bef47 MJ |
2331 | static |
2332 | void ust_context_ns_reset(void) | |
2333 | { | |
2334 | lttng_context_pid_ns_reset(); | |
2335 | lttng_context_cgroup_ns_reset(); | |
2336 | lttng_context_ipc_ns_reset(); | |
2337 | lttng_context_mnt_ns_reset(); | |
2338 | lttng_context_net_ns_reset(); | |
2339 | lttng_context_user_ns_reset(); | |
cefef7a7 | 2340 | lttng_context_time_ns_reset(); |
735bef47 MJ |
2341 | lttng_context_uts_ns_reset(); |
2342 | } | |
2343 | ||
fca2f191 MJ |
2344 | static |
2345 | void ust_context_vuids_reset(void) | |
2346 | { | |
2347 | lttng_context_vuid_reset(); | |
2348 | lttng_context_veuid_reset(); | |
2349 | lttng_context_vsuid_reset(); | |
2350 | } | |
2351 | ||
2352 | static | |
2353 | void ust_context_vgids_reset(void) | |
2354 | { | |
2355 | lttng_context_vgid_reset(); | |
2356 | lttng_context_vegid_reset(); | |
2357 | lttng_context_vsgid_reset(); | |
2358 | } | |
2359 | ||
e822f505 MD |
2360 | /* |
2361 | * We exclude the worker threads across fork and clone (except | |
2362 | * CLONE_VM), because these system calls only keep the forking thread | |
2363 | * running in the child. Therefore, we don't want to call fork or clone | |
2364 | * in the middle of an tracepoint or ust tracing state modification. | |
2365 | * Holding this mutex protects these structures across fork and clone. | |
2366 | */ | |
d0c8f180 | 2367 | void lttng_ust_before_fork(sigset_t *save_sigset) |
e822f505 MD |
2368 | { |
2369 | /* | |
2370 | * Disable signals. This is to avoid that the child intervenes | |
2371 | * before it is properly setup for tracing. It is safer to | |
2372 | * disable all signals, because then we know we are not breaking | |
2373 | * anything by restoring the original mask. | |
2374 | */ | |
2375 | sigset_t all_sigs; | |
2376 | int ret; | |
2377 | ||
a9fd951a MJ |
2378 | /* Allocate lttng-ust TLS. */ |
2379 | lttng_ust_alloc_tls(); | |
c362addf | 2380 | |
8c90a710 | 2381 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 2382 | return; |
e822f505 MD |
2383 | /* Disable signals */ |
2384 | sigfillset(&all_sigs); | |
b728d87e | 2385 | ret = sigprocmask(SIG_BLOCK, &all_sigs, save_sigset); |
e822f505 MD |
2386 | if (ret == -1) { |
2387 | PERROR("sigprocmask"); | |
2388 | } | |
458d678c PW |
2389 | |
2390 | pthread_mutex_lock(&ust_fork_mutex); | |
2391 | ||
3327ac33 | 2392 | ust_lock_nocheck(); |
10544ee8 | 2393 | lttng_ust_urcu_before_fork(); |
c1be081a | 2394 | lttng_ust_lock_fd_tracker(); |
20142124 | 2395 | lttng_perf_lock(); |
e822f505 MD |
2396 | } |
2397 | ||
b728d87e | 2398 | static void ust_after_fork_common(sigset_t *restore_sigset) |
e822f505 MD |
2399 | { |
2400 | int ret; | |
2401 | ||
17dfb34b | 2402 | DBG("process %d", getpid()); |
20142124 | 2403 | lttng_perf_unlock(); |
c1be081a | 2404 | lttng_ust_unlock_fd_tracker(); |
17dfb34b | 2405 | ust_unlock(); |
458d678c PW |
2406 | |
2407 | pthread_mutex_unlock(&ust_fork_mutex); | |
2408 | ||
e822f505 | 2409 | /* Restore signals */ |
23c8854a | 2410 | ret = sigprocmask(SIG_SETMASK, restore_sigset, NULL); |
e822f505 MD |
2411 | if (ret == -1) { |
2412 | PERROR("sigprocmask"); | |
2413 | } | |
2414 | } | |
2415 | ||
d0c8f180 | 2416 | void lttng_ust_after_fork_parent(sigset_t *restore_sigset) |
e822f505 | 2417 | { |
8c90a710 | 2418 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 2419 | return; |
17dfb34b | 2420 | DBG("process %d", getpid()); |
10544ee8 | 2421 | lttng_ust_urcu_after_fork_parent(); |
e822f505 | 2422 | /* Release mutexes and reenable signals */ |
b728d87e | 2423 | ust_after_fork_common(restore_sigset); |
e822f505 MD |
2424 | } |
2425 | ||
17dfb34b MD |
2426 | /* |
2427 | * After fork, in the child, we need to cleanup all the leftover state, | |
2428 | * except the worker thread which already magically disappeared thanks | |
2429 | * to the weird Linux fork semantics. After tyding up, we call | |
fca97dfd | 2430 | * lttng_ust_ctor() again to start over as a new PID. |
17dfb34b MD |
2431 | * |
2432 | * This is meant for forks() that have tracing in the child between the | |
2433 | * fork and following exec call (if there is any). | |
2434 | */ | |
d0c8f180 | 2435 | void lttng_ust_after_fork_child(sigset_t *restore_sigset) |
e822f505 | 2436 | { |
8c90a710 | 2437 | if (URCU_TLS(lttng_ust_nest_count)) |
e8508a49 | 2438 | return; |
06b16a0b | 2439 | lttng_context_vpid_reset(); |
8478887d | 2440 | lttng_context_vtid_reset(); |
0af0bdb2 | 2441 | lttng_ust_context_procname_reset(); |
735bef47 | 2442 | ust_context_ns_reset(); |
fca2f191 MJ |
2443 | ust_context_vuids_reset(); |
2444 | ust_context_vgids_reset(); | |
17dfb34b | 2445 | DBG("process %d", getpid()); |
e822f505 | 2446 | /* Release urcu mutexes */ |
10544ee8 | 2447 | lttng_ust_urcu_after_fork_child(); |
17dfb34b | 2448 | lttng_ust_cleanup(0); |
e822f505 | 2449 | /* Release mutexes and reenable signals */ |
b728d87e | 2450 | ust_after_fork_common(restore_sigset); |
fca97dfd | 2451 | lttng_ust_ctor(); |
e822f505 | 2452 | } |
95c25348 | 2453 | |
d0c8f180 | 2454 | void lttng_ust_after_setns(void) |
735bef47 MJ |
2455 | { |
2456 | ust_context_ns_reset(); | |
fca2f191 MJ |
2457 | ust_context_vuids_reset(); |
2458 | ust_context_vgids_reset(); | |
735bef47 MJ |
2459 | } |
2460 | ||
d0c8f180 | 2461 | void lttng_ust_after_unshare(void) |
735bef47 MJ |
2462 | { |
2463 | ust_context_ns_reset(); | |
fca2f191 MJ |
2464 | ust_context_vuids_reset(); |
2465 | ust_context_vgids_reset(); | |
2466 | } | |
2467 | ||
d0c8f180 | 2468 | void lttng_ust_after_setuid(void) |
fca2f191 MJ |
2469 | { |
2470 | ust_context_vuids_reset(); | |
2471 | } | |
2472 | ||
d0c8f180 | 2473 | void lttng_ust_after_seteuid(void) |
fca2f191 MJ |
2474 | { |
2475 | ust_context_vuids_reset(); | |
2476 | } | |
2477 | ||
d0c8f180 | 2478 | void lttng_ust_after_setreuid(void) |
fca2f191 MJ |
2479 | { |
2480 | ust_context_vuids_reset(); | |
2481 | } | |
2482 | ||
d0c8f180 | 2483 | void lttng_ust_after_setresuid(void) |
fca2f191 MJ |
2484 | { |
2485 | ust_context_vuids_reset(); | |
2486 | } | |
2487 | ||
d0c8f180 | 2488 | void lttng_ust_after_setgid(void) |
fca2f191 MJ |
2489 | { |
2490 | ust_context_vgids_reset(); | |
2491 | } | |
2492 | ||
d0c8f180 | 2493 | void lttng_ust_after_setegid(void) |
fca2f191 MJ |
2494 | { |
2495 | ust_context_vgids_reset(); | |
2496 | } | |
2497 | ||
d0c8f180 | 2498 | void lttng_ust_after_setregid(void) |
fca2f191 MJ |
2499 | { |
2500 | ust_context_vgids_reset(); | |
2501 | } | |
2502 | ||
d0c8f180 | 2503 | void lttng_ust_after_setresgid(void) |
fca2f191 MJ |
2504 | { |
2505 | ust_context_vgids_reset(); | |
735bef47 MJ |
2506 | } |
2507 | ||
246be17e | 2508 | void lttng_ust_sockinfo_session_enabled(void *owner) |
95c25348 PW |
2509 | { |
2510 | struct sock_info *sock_info = owner; | |
37dddb65 | 2511 | sock_info->statedump_pending = 1; |
95c25348 | 2512 | } |