Commit | Line | Data |
---|---|---|
1785d7f2 | 1 | /* |
90c106c6 | 2 | * Copyright (C) 2011 EfficiOS Inc. |
ab5be9fa MJ |
3 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
4 | * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com> | |
1785d7f2 | 5 | * |
ab5be9fa | 6 | * SPDX-License-Identifier: GPL-2.0-only |
1785d7f2 | 7 | * |
1785d7f2 JG |
8 | */ |
9 | ||
10 | #include <stddef.h> | |
11 | #include <stdlib.h> | |
12 | #include <urcu.h> | |
13 | #include <common/futex.h> | |
14 | #include <common/macros.h> | |
b7fc068d | 15 | #include <common/shm.h> |
1785d7f2 JG |
16 | #include <common/utils.h> |
17 | #include <sys/stat.h> | |
18 | ||
19 | #include "register.h" | |
20 | #include "lttng-sessiond.h" | |
21 | #include "testpoint.h" | |
22 | #include "health-sessiond.h" | |
23 | #include "fd-limit.h" | |
1785d7f2 JG |
24 | #include "utils.h" |
25 | #include "thread.h" | |
26 | ||
a13091b7 | 27 | struct thread_state { |
1785d7f2 JG |
28 | struct lttng_pipe *quit_pipe; |
29 | struct ust_cmd_queue *ust_cmd_queue; | |
9c9d917c | 30 | sem_t ready; |
86d0f119 | 31 | bool running; |
a13091b7 | 32 | int application_socket; |
1785d7f2 JG |
33 | }; |
34 | ||
35 | /* | |
36 | * Creates the application socket. | |
37 | */ | |
38 | static int create_application_socket(void) | |
39 | { | |
40 | int ret = 0; | |
41 | int apps_sock; | |
1785d7f2 JG |
42 | |
43 | /* Create the application unix socket */ | |
412d7227 SM |
44 | apps_sock = lttcomm_create_unix_sock( |
45 | the_config.apps_unix_sock_path.value); | |
1785d7f2 | 46 | if (apps_sock < 0) { |
412d7227 SM |
47 | ERR("Create unix sock failed: %s", |
48 | the_config.apps_unix_sock_path.value); | |
1785d7f2 JG |
49 | ret = -1; |
50 | goto end; | |
51 | } | |
52 | ||
53 | /* Set the cloexec flag */ | |
54 | ret = utils_set_fd_cloexec(apps_sock); | |
55 | if (ret < 0) { | |
56 | ERR("Unable to set CLOEXEC flag to the app Unix socket (fd: %d). " | |
57 | "Continuing but note that the consumer daemon will have a " | |
58 | "reference to this socket on exec()", apps_sock); | |
59 | } | |
60 | ||
61 | /* File permission MUST be 666 */ | |
412d7227 SM |
62 | ret = chmod(the_config.apps_unix_sock_path.value, |
63 | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | | |
64 | S_IWOTH); | |
1785d7f2 JG |
65 | if (ret < 0) { |
66 | PERROR("Set file permissions failed on %s", | |
412d7227 | 67 | the_config.apps_unix_sock_path.value); |
d9c6b5f2 | 68 | goto error_close_socket; |
1785d7f2 JG |
69 | } |
70 | ||
71 | DBG3("Session daemon application socket created (fd = %d) ", apps_sock); | |
72 | ret = apps_sock; | |
73 | end: | |
1785d7f2 | 74 | return ret; |
d9c6b5f2 JG |
75 | error_close_socket: |
76 | if (close(apps_sock)) { | |
77 | PERROR("Failed to close application socket in error path"); | |
78 | } | |
79 | apps_sock = -1; | |
80 | ret = -1; | |
81 | goto end; | |
1785d7f2 JG |
82 | } |
83 | ||
84 | /* | |
85 | * Notify UST applications using the shm mmap futex. | |
86 | */ | |
87 | static int notify_ust_apps(int active, bool is_root) | |
88 | { | |
89 | char *wait_shm_mmap; | |
90 | ||
91 | DBG("Notifying applications of session daemon state: %d", active); | |
92 | ||
93 | /* See shm.c for this call implying mmap, shm and futex calls */ | |
412d7227 SM |
94 | wait_shm_mmap = shm_ust_get_mmap( |
95 | the_config.wait_shm_path.value, is_root); | |
1785d7f2 JG |
96 | if (wait_shm_mmap == NULL) { |
97 | goto error; | |
98 | } | |
99 | ||
100 | /* Wake waiting process */ | |
101 | futex_wait_update((int32_t *) wait_shm_mmap, active); | |
102 | ||
103 | /* Apps notified successfully */ | |
104 | return 0; | |
105 | ||
106 | error: | |
107 | return -1; | |
108 | } | |
109 | ||
110 | static void cleanup_application_registration_thread(void *data) | |
111 | { | |
a13091b7 | 112 | struct thread_state *thread_state = data; |
1785d7f2 | 113 | |
a13091b7 JG |
114 | if (!data) { |
115 | return; | |
116 | } | |
117 | ||
118 | lttng_pipe_destroy(thread_state->quit_pipe); | |
119 | free(thread_state); | |
1785d7f2 JG |
120 | } |
121 | ||
a13091b7 | 122 | static void set_thread_status(struct thread_state *thread_state, bool running) |
9c9d917c | 123 | { |
86d0f119 | 124 | DBG("Marking application registration thread's state as %s", running ? "running" : "error"); |
a13091b7 JG |
125 | thread_state->running = running; |
126 | sem_post(&thread_state->ready); | |
9c9d917c JG |
127 | } |
128 | ||
a13091b7 | 129 | static bool wait_thread_status(struct thread_state *thread_state) |
9c9d917c JG |
130 | { |
131 | DBG("Waiting for application registration thread to be ready"); | |
a13091b7 JG |
132 | sem_wait(&thread_state->ready); |
133 | if (thread_state->running) { | |
86d0f119 JG |
134 | DBG("Application registration thread is ready"); |
135 | } else { | |
136 | ERR("Initialization of application registration thread failed"); | |
137 | } | |
138 | ||
a13091b7 | 139 | return thread_state->running; |
86d0f119 JG |
140 | } |
141 | ||
142 | static void thread_init_cleanup(void *data) | |
143 | { | |
a13091b7 | 144 | struct thread_state *thread_state = data; |
86d0f119 | 145 | |
a13091b7 | 146 | set_thread_status(thread_state, false); |
9c9d917c JG |
147 | } |
148 | ||
1785d7f2 JG |
149 | /* |
150 | * This thread manage application registration. | |
151 | */ | |
152 | static void *thread_application_registration(void *data) | |
153 | { | |
154 | int sock = -1, i, ret, pollfd, err = -1; | |
1785d7f2 JG |
155 | uint32_t revents, nb_fd; |
156 | struct lttng_poll_event events; | |
157 | /* | |
158 | * Gets allocated in this thread, enqueued to a global queue, dequeued | |
159 | * and freed in the manage apps thread. | |
160 | */ | |
161 | struct ust_command *ust_cmd = NULL; | |
162 | const bool is_root = (getuid() == 0); | |
a13091b7 JG |
163 | struct thread_state *thread_state = data; |
164 | const int application_socket = thread_state->application_socket; | |
1785d7f2 | 165 | const int quit_pipe_read_fd = lttng_pipe_get_readfd( |
a13091b7 | 166 | thread_state->quit_pipe); |
1785d7f2 JG |
167 | |
168 | DBG("[thread] Manage application registration started"); | |
169 | ||
a0b34569 | 170 | pthread_cleanup_push(thread_init_cleanup, thread_state); |
412d7227 | 171 | health_register(the_health_sessiond, HEALTH_SESSIOND_TYPE_APP_REG); |
1785d7f2 | 172 | |
a13091b7 | 173 | ret = lttcomm_listen_unix_sock(application_socket); |
1785d7f2 JG |
174 | if (ret < 0) { |
175 | goto error_listen; | |
176 | } | |
177 | ||
178 | /* | |
179 | * Pass 2 as size here for the thread quit pipe and apps_sock. Nothing | |
180 | * more will be added to this poll set. | |
181 | */ | |
182 | ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC); | |
183 | if (ret < 0) { | |
184 | goto error_create_poll; | |
185 | } | |
186 | ||
187 | /* Add the application registration socket */ | |
a13091b7 | 188 | ret = lttng_poll_add(&events, application_socket, LPOLLIN | LPOLLRDHUP); |
1785d7f2 JG |
189 | if (ret < 0) { |
190 | goto error_poll_add; | |
191 | } | |
192 | ||
193 | /* Add the application registration socket */ | |
194 | ret = lttng_poll_add(&events, quit_pipe_read_fd, LPOLLIN | LPOLLRDHUP); | |
195 | if (ret < 0) { | |
196 | goto error_poll_add; | |
197 | } | |
198 | ||
a13091b7 JG |
199 | set_thread_status(thread_state, true); |
200 | pthread_cleanup_pop(0); | |
1785d7f2 | 201 | |
9ad83bb6 JR |
202 | if (testpoint(sessiond_thread_registration_apps)) { |
203 | goto error_poll_add; | |
204 | } | |
205 | ||
1785d7f2 JG |
206 | while (1) { |
207 | DBG("Accepting application registration"); | |
208 | ||
209 | /* Inifinite blocking call, waiting for transmission */ | |
210 | restart: | |
211 | health_poll_entry(); | |
212 | ret = lttng_poll_wait(&events, -1); | |
213 | health_poll_exit(); | |
214 | if (ret < 0) { | |
215 | /* | |
216 | * Restart interrupted system call. | |
217 | */ | |
218 | if (errno == EINTR) { | |
219 | goto restart; | |
220 | } | |
221 | goto error; | |
222 | } | |
223 | ||
224 | nb_fd = ret; | |
225 | ||
226 | for (i = 0; i < nb_fd; i++) { | |
227 | health_code_update(); | |
228 | ||
229 | /* Fetch once the poll data */ | |
230 | revents = LTTNG_POLL_GETEV(&events, i); | |
231 | pollfd = LTTNG_POLL_GETFD(&events, i); | |
232 | ||
1785d7f2 JG |
233 | /* Thread quit pipe has been closed. Killing thread. */ |
234 | if (pollfd == quit_pipe_read_fd) { | |
235 | err = 0; | |
236 | goto exit; | |
237 | } else { | |
238 | /* Event on the registration socket */ | |
239 | if (revents & LPOLLIN) { | |
a13091b7 | 240 | sock = lttcomm_accept_unix_sock(application_socket); |
1785d7f2 JG |
241 | if (sock < 0) { |
242 | goto error; | |
243 | } | |
244 | ||
245 | /* | |
246 | * Set socket timeout for both receiving and ending. | |
247 | * app_socket_timeout is in seconds, whereas | |
248 | * lttcomm_setsockopt_rcv_timeout and | |
249 | * lttcomm_setsockopt_snd_timeout expect msec as | |
250 | * parameter. | |
251 | */ | |
412d7227 | 252 | if (the_config.app_socket_timeout >= 0) { |
1785d7f2 | 253 | (void) lttcomm_setsockopt_rcv_timeout(sock, |
412d7227 | 254 | the_config.app_socket_timeout * 1000); |
1785d7f2 | 255 | (void) lttcomm_setsockopt_snd_timeout(sock, |
412d7227 | 256 | the_config.app_socket_timeout * 1000); |
1785d7f2 JG |
257 | } |
258 | ||
259 | /* | |
260 | * Set the CLOEXEC flag. Return code is useless because | |
261 | * either way, the show must go on. | |
262 | */ | |
263 | (void) utils_set_fd_cloexec(sock); | |
264 | ||
265 | /* Create UST registration command for enqueuing */ | |
266 | ust_cmd = zmalloc(sizeof(struct ust_command)); | |
267 | if (ust_cmd == NULL) { | |
268 | PERROR("ust command zmalloc"); | |
269 | ret = close(sock); | |
270 | if (ret) { | |
271 | PERROR("close"); | |
272 | } | |
229afb9c | 273 | sock = -1; |
1785d7f2 JG |
274 | goto error; |
275 | } | |
276 | ||
277 | /* | |
278 | * Using message-based transmissions to ensure we don't | |
279 | * have to deal with partially received messages. | |
280 | */ | |
281 | ret = lttng_fd_get(LTTNG_FD_APPS, 1); | |
282 | if (ret < 0) { | |
283 | ERR("Exhausted file descriptors allowed for applications."); | |
284 | free(ust_cmd); | |
285 | ret = close(sock); | |
286 | if (ret) { | |
287 | PERROR("close"); | |
288 | } | |
289 | sock = -1; | |
290 | continue; | |
291 | } | |
292 | ||
293 | health_code_update(); | |
294 | ret = ust_app_recv_registration(sock, &ust_cmd->reg_msg); | |
295 | if (ret < 0) { | |
296 | free(ust_cmd); | |
297 | /* Close socket of the application. */ | |
298 | ret = close(sock); | |
299 | if (ret) { | |
300 | PERROR("close"); | |
301 | } | |
302 | lttng_fd_put(LTTNG_FD_APPS, 1); | |
303 | sock = -1; | |
304 | continue; | |
305 | } | |
306 | health_code_update(); | |
307 | ||
308 | ust_cmd->sock = sock; | |
309 | sock = -1; | |
310 | ||
311 | DBG("UST registration received with pid:%d ppid:%d uid:%d" | |
312 | " gid:%d sock:%d name:%s (version %d.%d)", | |
313 | ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid, | |
314 | ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid, | |
315 | ust_cmd->sock, ust_cmd->reg_msg.name, | |
316 | ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor); | |
317 | ||
318 | /* | |
319 | * Lock free enqueue the registration request. The red pill | |
320 | * has been taken! This apps will be part of the *system*. | |
321 | */ | |
a13091b7 JG |
322 | cds_wfcq_enqueue(&thread_state->ust_cmd_queue->head, |
323 | &thread_state->ust_cmd_queue->tail, | |
1785d7f2 JG |
324 | &ust_cmd->node); |
325 | ||
326 | /* | |
327 | * Wake the registration queue futex. Implicit memory | |
328 | * barrier with the exchange in cds_wfcq_enqueue. | |
329 | */ | |
a13091b7 | 330 | futex_nto1_wake(&thread_state->ust_cmd_queue->futex); |
1785d7f2 JG |
331 | } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { |
332 | ERR("Register apps socket poll error"); | |
333 | goto error; | |
334 | } else { | |
335 | ERR("Unexpected poll events %u for sock %d", revents, pollfd); | |
336 | goto error; | |
337 | } | |
338 | } | |
339 | } | |
340 | } | |
341 | ||
342 | exit: | |
343 | error: | |
344 | /* Notify that the registration thread is gone */ | |
345 | notify_ust_apps(0, is_root); | |
346 | ||
a13091b7 JG |
347 | ret = close(application_socket); |
348 | if (ret) { | |
349 | PERROR("Failed to close application registration socket"); | |
1785d7f2 JG |
350 | } |
351 | if (sock >= 0) { | |
352 | ret = close(sock); | |
353 | if (ret) { | |
a13091b7 | 354 | PERROR("Failed to close application socket"); |
1785d7f2 JG |
355 | } |
356 | lttng_fd_put(LTTNG_FD_APPS, 1); | |
357 | } | |
412d7227 | 358 | unlink(the_config.apps_unix_sock_path.value); |
1785d7f2 JG |
359 | |
360 | error_poll_add: | |
361 | lttng_poll_clean(&events); | |
362 | error_listen: | |
363 | error_create_poll: | |
1785d7f2 JG |
364 | DBG("UST Registration thread cleanup complete"); |
365 | if (err) { | |
366 | health_error(); | |
367 | ERR("Health error occurred in %s", __func__); | |
368 | } | |
412d7227 | 369 | health_unregister(the_health_sessiond); |
1785d7f2 JG |
370 | return NULL; |
371 | } | |
372 | ||
373 | static bool shutdown_application_registration_thread(void *data) | |
374 | { | |
a13091b7 JG |
375 | struct thread_state *thread_state = data; |
376 | const int write_fd = lttng_pipe_get_writefd(thread_state->quit_pipe); | |
1785d7f2 JG |
377 | |
378 | return notify_thread_pipe(write_fd) == 1; | |
379 | } | |
380 | ||
bd9addf7 | 381 | struct lttng_thread *launch_application_registration_thread( |
1785d7f2 JG |
382 | struct ust_cmd_queue *cmd_queue) |
383 | { | |
a13091b7 | 384 | int ret; |
1785d7f2 | 385 | struct lttng_pipe *quit_pipe; |
a13091b7 JG |
386 | struct thread_state *thread_state = NULL; |
387 | struct lttng_thread *thread = NULL; | |
388 | const bool is_root = (getuid() == 0); | |
389 | int application_socket = -1; | |
1785d7f2 | 390 | |
a13091b7 JG |
391 | thread_state = zmalloc(sizeof(*thread_state)); |
392 | if (!thread_state) { | |
21fa020e JG |
393 | goto error_alloc; |
394 | } | |
395 | quit_pipe = lttng_pipe_open(FD_CLOEXEC); | |
396 | if (!quit_pipe) { | |
1785d7f2 JG |
397 | goto error; |
398 | } | |
a13091b7 JG |
399 | thread_state->quit_pipe = quit_pipe; |
400 | thread_state->ust_cmd_queue = cmd_queue; | |
401 | application_socket = create_application_socket(); | |
402 | if (application_socket < 0) { | |
403 | goto error; | |
404 | } | |
405 | thread_state->application_socket = application_socket; | |
406 | sem_init(&thread_state->ready, 0, 0); | |
1785d7f2 JG |
407 | |
408 | thread = lttng_thread_create("UST application registration", | |
409 | thread_application_registration, | |
410 | shutdown_application_registration_thread, | |
411 | cleanup_application_registration_thread, | |
a13091b7 | 412 | thread_state); |
1785d7f2 JG |
413 | if (!thread) { |
414 | goto error; | |
415 | } | |
a13091b7 JG |
416 | /* |
417 | * The application registration thread now owns the application socket | |
418 | * and the global thread state. The thread state is used to wait for | |
419 | * the thread's status, but its ownership now belongs to the thread. | |
420 | */ | |
421 | application_socket = -1; | |
422 | if (!wait_thread_status(thread_state)) { | |
423 | thread_state = NULL; | |
424 | goto error; | |
86d0f119 | 425 | } |
a13091b7 JG |
426 | |
427 | /* Notify all applications to register. */ | |
428 | ret = notify_ust_apps(1, is_root); | |
429 | if (ret < 0) { | |
430 | ERR("Failed to notify applications or create the wait shared memory.\n" | |
431 | "Execution continues but there might be problems for already\n" | |
432 | "running applications that wishes to register."); | |
433 | } | |
434 | ||
bd9addf7 | 435 | return thread; |
1785d7f2 | 436 | error: |
a13091b7 JG |
437 | lttng_thread_put(thread); |
438 | cleanup_application_registration_thread(thread_state); | |
439 | if (application_socket >= 0) { | |
440 | if (close(application_socket)) { | |
441 | PERROR("Failed to close application registration socket"); | |
442 | } | |
443 | } | |
21fa020e | 444 | error_alloc: |
bd9addf7 | 445 | return NULL; |
1785d7f2 | 446 | } |