Commit | Line | Data |
---|---|---|
1785d7f2 | 1 | /* |
21cf9b6b | 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 | ||
28ab034a JG |
10 | #include "fd-limit.hpp" |
11 | #include "health-sessiond.hpp" | |
12 | #include "lttng-sessiond.hpp" | |
13 | #include "register.hpp" | |
14 | #include "testpoint.hpp" | |
15 | #include "thread.hpp" | |
16 | #include "utils.hpp" | |
17 | ||
c9e313bc SM |
18 | #include <common/futex.hpp> |
19 | #include <common/macros.hpp> | |
20 | #include <common/shm.hpp> | |
21 | #include <common/utils.hpp> | |
1785d7f2 | 22 | |
28ab034a JG |
23 | #include <stddef.h> |
24 | #include <stdlib.h> | |
25 | #include <sys/stat.h> | |
26 | #include <urcu.h> | |
1785d7f2 | 27 | |
f1494934 | 28 | namespace { |
a13091b7 | 29 | struct thread_state { |
1785d7f2 JG |
30 | struct lttng_pipe *quit_pipe; |
31 | struct ust_cmd_queue *ust_cmd_queue; | |
9c9d917c | 32 | sem_t ready; |
86d0f119 | 33 | bool running; |
a13091b7 | 34 | int application_socket; |
1785d7f2 | 35 | }; |
f1494934 | 36 | } /* namespace */ |
1785d7f2 JG |
37 | |
38 | /* | |
39 | * Creates the application socket. | |
40 | */ | |
cd9adb8b | 41 | static int create_application_socket() |
1785d7f2 JG |
42 | { |
43 | int ret = 0; | |
44 | int apps_sock; | |
1785d7f2 JG |
45 | |
46 | /* Create the application unix socket */ | |
28ab034a | 47 | apps_sock = lttcomm_create_unix_sock(the_config.apps_unix_sock_path.value); |
1785d7f2 | 48 | if (apps_sock < 0) { |
28ab034a | 49 | ERR("Create unix sock failed: %s", the_config.apps_unix_sock_path.value); |
1785d7f2 JG |
50 | ret = -1; |
51 | goto end; | |
52 | } | |
53 | ||
54 | /* Set the cloexec flag */ | |
55 | ret = utils_set_fd_cloexec(apps_sock); | |
56 | if (ret < 0) { | |
57 | ERR("Unable to set CLOEXEC flag to the app Unix socket (fd: %d). " | |
28ab034a JG |
58 | "Continuing but note that the consumer daemon will have a " |
59 | "reference to this socket on exec()", | |
60 | apps_sock); | |
1785d7f2 JG |
61 | } |
62 | ||
63 | /* File permission MUST be 666 */ | |
412d7227 | 64 | ret = chmod(the_config.apps_unix_sock_path.value, |
28ab034a | 65 | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH); |
1785d7f2 | 66 | if (ret < 0) { |
28ab034a | 67 | PERROR("Set file permissions failed on %s", 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 */ | |
28ab034a | 94 | wait_shm_mmap = shm_ust_get_mmap(the_config.wait_shm_path.value, is_root); |
cd9adb8b | 95 | if (wait_shm_mmap == nullptr) { |
1785d7f2 JG |
96 | goto error; |
97 | } | |
98 | ||
99 | /* Wake waiting process */ | |
100 | futex_wait_update((int32_t *) wait_shm_mmap, active); | |
101 | ||
102 | /* Apps notified successfully */ | |
103 | return 0; | |
104 | ||
105 | error: | |
106 | return -1; | |
107 | } | |
108 | ||
109 | static void cleanup_application_registration_thread(void *data) | |
110 | { | |
7966af57 | 111 | struct thread_state *thread_state = (struct thread_state *) data; |
1785d7f2 | 112 | |
a13091b7 JG |
113 | if (!data) { |
114 | return; | |
115 | } | |
116 | ||
117 | lttng_pipe_destroy(thread_state->quit_pipe); | |
118 | free(thread_state); | |
1785d7f2 JG |
119 | } |
120 | ||
a13091b7 | 121 | static void set_thread_status(struct thread_state *thread_state, bool running) |
9c9d917c | 122 | { |
86d0f119 | 123 | DBG("Marking application registration thread's state as %s", running ? "running" : "error"); |
a13091b7 JG |
124 | thread_state->running = running; |
125 | sem_post(&thread_state->ready); | |
9c9d917c JG |
126 | } |
127 | ||
a13091b7 | 128 | static bool wait_thread_status(struct thread_state *thread_state) |
9c9d917c JG |
129 | { |
130 | DBG("Waiting for application registration thread to be ready"); | |
a13091b7 JG |
131 | sem_wait(&thread_state->ready); |
132 | if (thread_state->running) { | |
86d0f119 JG |
133 | DBG("Application registration thread is ready"); |
134 | } else { | |
135 | ERR("Initialization of application registration thread failed"); | |
136 | } | |
137 | ||
a13091b7 | 138 | return thread_state->running; |
86d0f119 JG |
139 | } |
140 | ||
141 | static void thread_init_cleanup(void *data) | |
142 | { | |
7966af57 | 143 | struct thread_state *thread_state = (struct thread_state *) data; |
86d0f119 | 144 | |
a13091b7 | 145 | set_thread_status(thread_state, false); |
9c9d917c JG |
146 | } |
147 | ||
1785d7f2 JG |
148 | /* |
149 | * This thread manage application registration. | |
150 | */ | |
151 | static void *thread_application_registration(void *data) | |
152 | { | |
8a00688e MJ |
153 | int sock = -1, i, ret, err = -1; |
154 | uint32_t nb_fd; | |
1785d7f2 JG |
155 | struct lttng_poll_event events; |
156 | /* | |
157 | * Gets allocated in this thread, enqueued to a global queue, dequeued | |
158 | * and freed in the manage apps thread. | |
159 | */ | |
cd9adb8b | 160 | struct ust_command *ust_cmd = nullptr; |
1785d7f2 | 161 | const bool is_root = (getuid() == 0); |
7966af57 | 162 | struct thread_state *thread_state = (struct thread_state *) data; |
a13091b7 | 163 | const int application_socket = thread_state->application_socket; |
28ab034a | 164 | const auto thread_quit_pipe_fd = lttng_pipe_get_readfd(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); |
412d7227 | 169 | health_register(the_health_sessiond, HEALTH_SESSIOND_TYPE_APP_REG); |
1785d7f2 | 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 */ | |
8a00688e | 192 | ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLRDHUP); |
1785d7f2 JG |
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 | ||
cd9adb8b | 204 | while (true) { |
1785d7f2 JG |
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 */ | |
8a00688e MJ |
228 | const auto revents = LTTNG_POLL_GETEV(&events, i); |
229 | const auto pollfd = LTTNG_POLL_GETFD(&events, i); | |
1785d7f2 | 230 | |
8a00688e MJ |
231 | /* Activity on thread quit pipe, closing. */ |
232 | if (pollfd == thread_quit_pipe_fd) { | |
1785d7f2 JG |
233 | err = 0; |
234 | goto exit; | |
8a00688e | 235 | } |
1785d7f2 | 236 | |
8a00688e MJ |
237 | /* Event on the registration socket. */ |
238 | if (revents & LPOLLIN) { | |
239 | sock = lttcomm_accept_unix_sock(application_socket); | |
240 | if (sock < 0) { | |
241 | goto error; | |
242 | } | |
1785d7f2 | 243 | |
8a00688e MJ |
244 | /* |
245 | * Set socket timeout for both receiving and ending. | |
246 | * app_socket_timeout is in seconds, whereas | |
247 | * lttcomm_setsockopt_rcv_timeout and | |
248 | * lttcomm_setsockopt_snd_timeout expect msec as | |
249 | * parameter. | |
250 | */ | |
251 | if (the_config.app_socket_timeout >= 0) { | |
28ab034a JG |
252 | (void) lttcomm_setsockopt_rcv_timeout( |
253 | sock, the_config.app_socket_timeout * 1000); | |
254 | (void) lttcomm_setsockopt_snd_timeout( | |
255 | sock, the_config.app_socket_timeout * 1000); | |
8a00688e | 256 | } |
1785d7f2 | 257 | |
8a00688e MJ |
258 | /* |
259 | * Set the CLOEXEC flag. Return code is useless because | |
260 | * either way, the show must go on. | |
261 | */ | |
262 | (void) utils_set_fd_cloexec(sock); | |
263 | ||
264 | /* Create UST registration command for enqueuing */ | |
265 | ust_cmd = zmalloc<ust_command>(); | |
cd9adb8b | 266 | if (ust_cmd == nullptr) { |
8a00688e MJ |
267 | PERROR("ust command zmalloc"); |
268 | ret = close(sock); | |
269 | if (ret) { | |
270 | PERROR("close"); | |
1785d7f2 | 271 | } |
8a00688e MJ |
272 | sock = -1; |
273 | goto error; | |
274 | } | |
1785d7f2 | 275 | |
8a00688e MJ |
276 | /* |
277 | * Using message-based transmissions to ensure we don't | |
278 | * have to deal with partially received messages. | |
279 | */ | |
280 | ret = lttng_fd_get(LTTNG_FD_APPS, 1); | |
281 | if (ret < 0) { | |
282 | ERR("Exhausted file descriptors allowed for applications."); | |
283 | free(ust_cmd); | |
284 | ret = close(sock); | |
285 | if (ret) { | |
286 | PERROR("close"); | |
1785d7f2 | 287 | } |
1785d7f2 | 288 | sock = -1; |
8a00688e MJ |
289 | continue; |
290 | } | |
1785d7f2 | 291 | |
8a00688e MJ |
292 | health_code_update(); |
293 | ret = ust_app_recv_registration(sock, &ust_cmd->reg_msg); | |
294 | if (ret < 0) { | |
295 | free(ust_cmd); | |
296 | /* Close socket of the application. */ | |
297 | ret = close(sock); | |
298 | if (ret) { | |
299 | PERROR("close"); | |
300 | } | |
301 | lttng_fd_put(LTTNG_FD_APPS, 1); | |
302 | sock = -1; | |
303 | continue; | |
1785d7f2 | 304 | } |
8a00688e MJ |
305 | health_code_update(); |
306 | ||
307 | ust_cmd->sock = sock; | |
308 | sock = -1; | |
309 | ||
310 | DBG("UST registration received with pid:%d ppid:%d uid:%d" | |
28ab034a JG |
311 | " gid:%d sock:%d name:%s (version %d.%d)", |
312 | ust_cmd->reg_msg.pid, | |
313 | ust_cmd->reg_msg.ppid, | |
314 | ust_cmd->reg_msg.uid, | |
315 | ust_cmd->reg_msg.gid, | |
316 | ust_cmd->sock, | |
317 | ust_cmd->reg_msg.name, | |
318 | ust_cmd->reg_msg.major, | |
319 | ust_cmd->reg_msg.minor); | |
8a00688e MJ |
320 | |
321 | /* | |
322 | * Lock free enqueue the registration request. The red pill | |
323 | * has been taken! This apps will be part of the *system*. | |
324 | */ | |
325 | cds_wfcq_head_ptr_t head; | |
326 | head.h = &thread_state->ust_cmd_queue->head; | |
28ab034a JG |
327 | cds_wfcq_enqueue( |
328 | head, &thread_state->ust_cmd_queue->tail, &ust_cmd->node); | |
8a00688e MJ |
329 | |
330 | /* | |
331 | * Wake the registration queue futex. Implicit memory | |
332 | * barrier with the exchange in cds_wfcq_enqueue. | |
333 | */ | |
334 | futex_nto1_wake(&thread_state->ust_cmd_queue->futex); | |
335 | } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { | |
336 | ERR("Register apps socket poll error"); | |
337 | goto error; | |
338 | } else { | |
339 | ERR("Unexpected poll events %u for sock %d", revents, pollfd); | |
340 | goto error; | |
1785d7f2 JG |
341 | } |
342 | } | |
343 | } | |
344 | ||
345 | exit: | |
346 | error: | |
347 | /* Notify that the registration thread is gone */ | |
348 | notify_ust_apps(0, is_root); | |
349 | ||
a13091b7 JG |
350 | ret = close(application_socket); |
351 | if (ret) { | |
352 | PERROR("Failed to close application registration socket"); | |
1785d7f2 JG |
353 | } |
354 | if (sock >= 0) { | |
355 | ret = close(sock); | |
356 | if (ret) { | |
a13091b7 | 357 | PERROR("Failed to close application socket"); |
1785d7f2 JG |
358 | } |
359 | lttng_fd_put(LTTNG_FD_APPS, 1); | |
360 | } | |
412d7227 | 361 | unlink(the_config.apps_unix_sock_path.value); |
1785d7f2 JG |
362 | |
363 | error_poll_add: | |
364 | lttng_poll_clean(&events); | |
365 | error_listen: | |
366 | error_create_poll: | |
1785d7f2 JG |
367 | DBG("UST Registration thread cleanup complete"); |
368 | if (err) { | |
369 | health_error(); | |
370 | ERR("Health error occurred in %s", __func__); | |
371 | } | |
412d7227 | 372 | health_unregister(the_health_sessiond); |
cd9adb8b | 373 | return nullptr; |
1785d7f2 JG |
374 | } |
375 | ||
376 | static bool shutdown_application_registration_thread(void *data) | |
377 | { | |
7966af57 | 378 | struct thread_state *thread_state = (struct thread_state *) data; |
a13091b7 | 379 | const int write_fd = lttng_pipe_get_writefd(thread_state->quit_pipe); |
1785d7f2 JG |
380 | |
381 | return notify_thread_pipe(write_fd) == 1; | |
382 | } | |
383 | ||
28ab034a | 384 | struct lttng_thread *launch_application_registration_thread(struct ust_cmd_queue *cmd_queue) |
1785d7f2 | 385 | { |
a13091b7 | 386 | int ret; |
1785d7f2 | 387 | struct lttng_pipe *quit_pipe; |
cd9adb8b JG |
388 | struct thread_state *thread_state = nullptr; |
389 | struct lttng_thread *thread = nullptr; | |
a13091b7 JG |
390 | const bool is_root = (getuid() == 0); |
391 | int application_socket = -1; | |
1785d7f2 | 392 | |
64803277 | 393 | thread_state = zmalloc<struct thread_state>(); |
a13091b7 | 394 | if (!thread_state) { |
21fa020e JG |
395 | goto error_alloc; |
396 | } | |
397 | quit_pipe = lttng_pipe_open(FD_CLOEXEC); | |
398 | if (!quit_pipe) { | |
1785d7f2 JG |
399 | goto error; |
400 | } | |
a13091b7 JG |
401 | thread_state->quit_pipe = quit_pipe; |
402 | thread_state->ust_cmd_queue = cmd_queue; | |
403 | application_socket = create_application_socket(); | |
404 | if (application_socket < 0) { | |
405 | goto error; | |
406 | } | |
407 | thread_state->application_socket = application_socket; | |
408 | sem_init(&thread_state->ready, 0, 0); | |
1785d7f2 JG |
409 | |
410 | thread = lttng_thread_create("UST application registration", | |
28ab034a JG |
411 | thread_application_registration, |
412 | shutdown_application_registration_thread, | |
413 | cleanup_application_registration_thread, | |
414 | thread_state); | |
1785d7f2 JG |
415 | if (!thread) { |
416 | goto error; | |
417 | } | |
a13091b7 JG |
418 | /* |
419 | * The application registration thread now owns the application socket | |
420 | * and the global thread state. The thread state is used to wait for | |
421 | * the thread's status, but its ownership now belongs to the thread. | |
422 | */ | |
423 | application_socket = -1; | |
424 | if (!wait_thread_status(thread_state)) { | |
cd9adb8b | 425 | thread_state = nullptr; |
a13091b7 | 426 | goto error; |
86d0f119 | 427 | } |
a13091b7 JG |
428 | |
429 | /* Notify all applications to register. */ | |
430 | ret = notify_ust_apps(1, is_root); | |
431 | if (ret < 0) { | |
432 | ERR("Failed to notify applications or create the wait shared memory.\n" | |
28ab034a JG |
433 | "Execution continues but there might be problems for already\n" |
434 | "running applications that wishes to register."); | |
a13091b7 JG |
435 | } |
436 | ||
bd9addf7 | 437 | return thread; |
1785d7f2 | 438 | error: |
a13091b7 JG |
439 | lttng_thread_put(thread); |
440 | cleanup_application_registration_thread(thread_state); | |
441 | if (application_socket >= 0) { | |
442 | if (close(application_socket)) { | |
443 | PERROR("Failed to close application registration socket"); | |
444 | } | |
445 | } | |
21fa020e | 446 | error_alloc: |
cd9adb8b | 447 | return nullptr; |
1785d7f2 | 448 | } |