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