Commit | Line | Data |
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1ce86c9a JD |
1 | /* |
2 | * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca> | |
3 | * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or | |
6 | * modify it under the terms of the GNU General Public License | |
82a3637f DG |
7 | * as published by the Free Software Foundation; only version 2 |
8 | * of the License. | |
1ce86c9a JD |
9 | * |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
18 | */ | |
19 | ||
20 | #define _GNU_SOURCE | |
21 | #include <fcntl.h> | |
22 | #include <poll.h> | |
23 | #include <pthread.h> | |
24 | #include <stdlib.h> | |
25 | #include <string.h> | |
26 | #include <sys/mman.h> | |
27 | #include <sys/socket.h> | |
28 | #include <sys/types.h> | |
29 | #include <unistd.h> | |
30 | #include <urcu/list.h> | |
5348b470 | 31 | #include <assert.h> |
6533b585 DG |
32 | |
33 | #include <lttng/lttng-kconsumerd.h> | |
1ce86c9a | 34 | |
50ecdf72 | 35 | #include "kernelctl.h" |
1ce86c9a | 36 | #include "lttngerr.h" |
6533b585 | 37 | #include "lttng-sessiond-comm.h" |
1ce86c9a | 38 | |
6533b585 | 39 | static struct lttng_kconsumerd_global_data { |
242cd187 MD |
40 | /* |
41 | * kconsumerd_data.lock protects kconsumerd_data.fd_list, | |
6533b585 DG |
42 | * kconsumerd_data.fds_count, and kconsumerd_data.need_update. It ensures |
43 | * the count matches the number of items in the fd_list. It ensures the | |
44 | * list updates *always* trigger an fd_array update (therefore need to make | |
45 | * list update vs kconsumerd_data.need_update flag update atomic, and also | |
46 | * flag read, fd array and flag clear atomic). | |
242cd187 MD |
47 | */ |
48 | pthread_mutex_t lock; | |
49 | /* | |
6533b585 | 50 | * Number of element for the list below. Protected by kconsumerd_data.lock. |
242cd187 MD |
51 | */ |
52 | unsigned int fds_count; | |
53 | /* | |
6533b585 | 54 | * List of FDs. Protected by kconsumerd_data.lock. |
242cd187 | 55 | */ |
6533b585 | 56 | struct lttng_kconsumerd_fd_list fd_list; |
242cd187 | 57 | /* |
6533b585 DG |
58 | * Flag specifying if the local array of FDs needs update in the poll |
59 | * function. Protected by kconsumerd_data.lock. | |
242cd187 MD |
60 | */ |
61 | unsigned int need_update; | |
62 | } kconsumerd_data = { | |
63 | .fd_list.head = CDS_LIST_HEAD_INIT(kconsumerd_data.fd_list.head), | |
cb040cc1 JD |
64 | .fds_count = 0, |
65 | .need_update = 1, | |
1ce86c9a JD |
66 | }; |
67 | ||
6533b585 | 68 | /* timeout parameter, to control the polling thread grace period. */ |
1ce86c9a JD |
69 | static int kconsumerd_poll_timeout = -1; |
70 | ||
3dcd2721 | 71 | /* |
6533b585 DG |
72 | * Flag to inform the polling thread to quit when all fd hung up. Updated by |
73 | * the kconsumerd_thread_receive_fds when it notices that all fds has hung up. | |
74 | * Also updated by the signal handler (kconsumerd_should_exit()). Read by the | |
75 | * polling threads. | |
3dcd2721 MD |
76 | */ |
77 | static volatile int kconsumerd_quit = 0; | |
1ce86c9a JD |
78 | |
79 | /* | |
6533b585 DG |
80 | * Find a session fd in the global list. The kconsumerd_data.lock must be |
81 | * locked during this call. | |
38079a1b | 82 | * |
6533b585 | 83 | * Return 1 if found else 0. |
38079a1b DG |
84 | */ |
85 | static int kconsumerd_find_session_fd(int fd) | |
86 | { | |
6533b585 | 87 | struct lttng_kconsumerd_fd *iter; |
38079a1b | 88 | |
242cd187 | 89 | cds_list_for_each_entry(iter, &kconsumerd_data.fd_list.head, list) { |
38079a1b DG |
90 | if (iter->sessiond_fd == fd) { |
91 | DBG("Duplicate session fd %d", fd); | |
38079a1b DG |
92 | return 1; |
93 | } | |
94 | } | |
38079a1b DG |
95 | |
96 | return 0; | |
97 | } | |
98 | ||
1ce86c9a | 99 | /* |
6533b585 | 100 | * Remove a fd from the global list protected by a mutex. |
1ce86c9a | 101 | */ |
6533b585 | 102 | static void kconsumerd_del_fd(struct lttng_kconsumerd_fd *lcf) |
1ce86c9a | 103 | { |
8b270bdb | 104 | int ret; |
242cd187 | 105 | pthread_mutex_lock(&kconsumerd_data.lock); |
1ce86c9a | 106 | cds_list_del(&lcf->list); |
242cd187 MD |
107 | if (kconsumerd_data.fds_count > 0) { |
108 | kconsumerd_data.fds_count--; | |
1ce86c9a | 109 | if (lcf != NULL) { |
8b270bdb JD |
110 | if (lcf->mmap_base != NULL) { |
111 | ret = munmap(lcf->mmap_base, lcf->mmap_len); | |
112 | if (ret != 0) { | |
113 | perror("munmap"); | |
114 | } | |
115 | } | |
cb040cc1 JD |
116 | if (lcf->out_fd != 0) { |
117 | close(lcf->out_fd); | |
118 | } | |
1ce86c9a JD |
119 | close(lcf->consumerd_fd); |
120 | free(lcf); | |
121 | lcf = NULL; | |
122 | } | |
123 | } | |
242cd187 MD |
124 | kconsumerd_data.need_update = 1; |
125 | pthread_mutex_unlock(&kconsumerd_data.lock); | |
1ce86c9a JD |
126 | } |
127 | ||
128 | /* | |
5348b470 JD |
129 | * Create a struct lttcomm_kconsumerd_msg from the |
130 | * information received on the receiving socket | |
1ce86c9a | 131 | */ |
5348b470 JD |
132 | struct lttng_kconsumerd_fd *kconsumerd_allocate_fd( |
133 | struct lttcomm_kconsumerd_msg *buf, | |
6533b585 | 134 | int consumerd_fd) |
1ce86c9a | 135 | { |
6533b585 | 136 | struct lttng_kconsumerd_fd *tmp_fd; |
38079a1b | 137 | |
5348b470 JD |
138 | tmp_fd = malloc(sizeof(struct lttng_kconsumerd_fd)); |
139 | if (tmp_fd == NULL) { | |
140 | perror("malloc struct lttng_kconsumerd_fd"); | |
38079a1b DG |
141 | goto end; |
142 | } | |
1ce86c9a | 143 | |
1ce86c9a JD |
144 | tmp_fd->sessiond_fd = buf->fd; |
145 | tmp_fd->consumerd_fd = consumerd_fd; | |
146 | tmp_fd->state = buf->state; | |
147 | tmp_fd->max_sb_size = buf->max_sb_size; | |
cb040cc1 JD |
148 | tmp_fd->out_fd = 0; |
149 | tmp_fd->out_fd_offset = 0; | |
8b270bdb JD |
150 | tmp_fd->mmap_len = 0; |
151 | tmp_fd->mmap_base = NULL; | |
152 | tmp_fd->output = buf->output; | |
1ce86c9a | 153 | strncpy(tmp_fd->path_name, buf->path_name, PATH_MAX); |
99497cd0 | 154 | tmp_fd->path_name[PATH_MAX - 1] = '\0'; |
5348b470 JD |
155 | DBG("Allocated %s (sessiond_fd %d, consumerd_fd %d, out_fd %d)", |
156 | tmp_fd->path_name, tmp_fd->sessiond_fd, | |
157 | tmp_fd->consumerd_fd, tmp_fd->out_fd); | |
1ce86c9a | 158 | |
5348b470 JD |
159 | end: |
160 | return tmp_fd; | |
161 | } | |
1ce86c9a | 162 | |
5348b470 JD |
163 | /* |
164 | * Add a fd to the global list protected by a mutex. | |
165 | */ | |
166 | static int kconsumerd_add_fd(struct lttng_kconsumerd_fd *tmp_fd) | |
167 | { | |
168 | int ret; | |
8b270bdb | 169 | |
5348b470 JD |
170 | pthread_mutex_lock(&kconsumerd_data.lock); |
171 | /* Check if already exist */ | |
172 | ret = kconsumerd_find_session_fd(tmp_fd->sessiond_fd); | |
173 | if (ret == 1) { | |
174 | goto end; | |
8b270bdb | 175 | } |
242cd187 MD |
176 | cds_list_add(&tmp_fd->list, &kconsumerd_data.fd_list.head); |
177 | kconsumerd_data.fds_count++; | |
178 | kconsumerd_data.need_update = 1; | |
5348b470 | 179 | |
1ce86c9a | 180 | end: |
242cd187 | 181 | pthread_mutex_unlock(&kconsumerd_data.lock); |
1ce86c9a JD |
182 | return ret; |
183 | } | |
184 | ||
185 | /* | |
6533b585 | 186 | * Update a fd according to what we just received. |
1ce86c9a JD |
187 | */ |
188 | static void kconsumerd_change_fd_state(int sessiond_fd, | |
6533b585 | 189 | enum lttng_kconsumerd_fd_state state) |
1ce86c9a | 190 | { |
6533b585 | 191 | struct lttng_kconsumerd_fd *iter; |
0237248c | 192 | |
242cd187 MD |
193 | pthread_mutex_lock(&kconsumerd_data.lock); |
194 | cds_list_for_each_entry(iter, &kconsumerd_data.fd_list.head, list) { | |
1ce86c9a JD |
195 | if (iter->sessiond_fd == sessiond_fd) { |
196 | iter->state = state; | |
197 | break; | |
198 | } | |
199 | } | |
242cd187 MD |
200 | kconsumerd_data.need_update = 1; |
201 | pthread_mutex_unlock(&kconsumerd_data.lock); | |
1ce86c9a JD |
202 | } |
203 | ||
204 | /* | |
6533b585 DG |
205 | * Allocate the pollfd structure and the local view of the out fds to avoid |
206 | * doing a lookup in the linked list and concurrency issues when writing is | |
207 | * needed. Called with kconsumerd_data.lock held. | |
1ce86c9a | 208 | * |
6533b585 | 209 | * Returns the number of fds in the structures. |
1ce86c9a | 210 | */ |
6533b585 DG |
211 | static int kconsumerd_update_poll_array( |
212 | struct lttng_kconsumerd_local_data *ctx, struct pollfd **pollfd, | |
213 | struct lttng_kconsumerd_fd **local_kconsumerd_fd) | |
1ce86c9a | 214 | { |
6533b585 | 215 | struct lttng_kconsumerd_fd *iter; |
1ce86c9a JD |
216 | int i = 0; |
217 | ||
218 | DBG("Updating poll fd array"); | |
242cd187 | 219 | cds_list_for_each_entry(iter, &kconsumerd_data.fd_list.head, list) { |
1ce86c9a JD |
220 | if (iter->state == ACTIVE_FD) { |
221 | DBG("Active FD %d", iter->consumerd_fd); | |
222 | (*pollfd)[i].fd = iter->consumerd_fd; | |
223 | (*pollfd)[i].events = POLLIN | POLLPRI; | |
224 | local_kconsumerd_fd[i] = iter; | |
225 | i++; | |
226 | } | |
227 | } | |
228 | ||
229 | /* | |
6533b585 DG |
230 | * Insert the kconsumerd_poll_pipe at the end of the array and don't |
231 | * increment i so nb_fd is the number of real FD. | |
1ce86c9a | 232 | */ |
cb040cc1 | 233 | (*pollfd)[i].fd = ctx->kconsumerd_poll_pipe[0]; |
1ce86c9a | 234 | (*pollfd)[i].events = POLLIN; |
1ce86c9a JD |
235 | return i; |
236 | } | |
237 | ||
6533b585 DG |
238 | /* |
239 | * Receives an array of file descriptors and the associated structures | |
240 | * describing each fd (path name). | |
241 | * | |
242 | * Returns the size of received data | |
243 | */ | |
244 | static int kconsumerd_consumerd_recv_fd( | |
245 | struct lttng_kconsumerd_local_data *ctx, int sfd, | |
246 | struct pollfd *kconsumerd_sockpoll, int size, | |
247 | enum lttng_kconsumerd_command cmd_type) | |
248 | { | |
249 | struct iovec iov[1]; | |
250 | int ret = 0, i, tmp2; | |
251 | struct cmsghdr *cmsg; | |
252 | int nb_fd; | |
253 | char recv_fd[CMSG_SPACE(sizeof(int))]; | |
254 | struct lttcomm_kconsumerd_msg lkm; | |
5348b470 | 255 | struct lttng_kconsumerd_fd *new_fd; |
6533b585 DG |
256 | |
257 | /* the number of fds we are about to receive */ | |
258 | nb_fd = size / sizeof(struct lttcomm_kconsumerd_msg); | |
259 | ||
260 | /* | |
261 | * nb_fd is the number of fds we receive. One fd per recvmsg. | |
262 | */ | |
263 | for (i = 0; i < nb_fd; i++) { | |
264 | struct msghdr msg = { 0 }; | |
265 | ||
266 | /* Prepare to receive the structures */ | |
267 | iov[0].iov_base = &lkm; | |
268 | iov[0].iov_len = sizeof(lkm); | |
269 | msg.msg_iov = iov; | |
270 | msg.msg_iovlen = 1; | |
271 | ||
272 | msg.msg_control = recv_fd; | |
273 | msg.msg_controllen = sizeof(recv_fd); | |
274 | ||
275 | DBG("Waiting to receive fd"); | |
276 | if (lttng_kconsumerd_poll_socket(kconsumerd_sockpoll) < 0) { | |
277 | goto end; | |
278 | } | |
279 | ||
280 | if ((ret = recvmsg(sfd, &msg, 0)) < 0) { | |
281 | perror("recvmsg"); | |
282 | continue; | |
283 | } | |
284 | ||
285 | if (ret != (size / nb_fd)) { | |
286 | ERR("Received only %d, expected %d", ret, size); | |
287 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_ERROR_RECV_FD); | |
288 | goto end; | |
289 | } | |
290 | ||
291 | cmsg = CMSG_FIRSTHDR(&msg); | |
292 | if (!cmsg) { | |
293 | ERR("Invalid control message header"); | |
294 | ret = -1; | |
295 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_ERROR_RECV_FD); | |
296 | goto end; | |
297 | } | |
298 | ||
299 | /* if we received fds */ | |
300 | if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) { | |
301 | switch (cmd_type) { | |
302 | case ADD_STREAM: | |
303 | DBG("kconsumerd_add_fd %s (%d)", lkm.path_name, | |
304 | ((int *) CMSG_DATA(cmsg))[0]); | |
305 | ||
5348b470 JD |
306 | new_fd = kconsumerd_allocate_fd(&lkm, ((int *) CMSG_DATA(cmsg))[0]); |
307 | if (new_fd == NULL) { | |
6533b585 DG |
308 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_OUTFD_ERROR); |
309 | goto end; | |
310 | } | |
5348b470 JD |
311 | |
312 | if (ctx->on_recv_fd != NULL) { | |
313 | ret = ctx->on_recv_fd(new_fd); | |
314 | if (ret == 0) { | |
315 | kconsumerd_add_fd(new_fd); | |
316 | } else if (ret < 0) { | |
317 | goto end; | |
318 | } | |
319 | } else { | |
320 | kconsumerd_add_fd(new_fd); | |
321 | } | |
6533b585 DG |
322 | break; |
323 | case UPDATE_STREAM: | |
5348b470 JD |
324 | if (ctx->on_update_fd != NULL) { |
325 | ret = ctx->on_update_fd(lkm.fd, lkm.state); | |
326 | if (ret == 0) { | |
327 | kconsumerd_change_fd_state(lkm.fd, lkm.state); | |
328 | } else if (ret < 0) { | |
329 | goto end; | |
330 | } | |
331 | } else { | |
332 | kconsumerd_change_fd_state(lkm.fd, lkm.state); | |
333 | } | |
6533b585 DG |
334 | break; |
335 | default: | |
336 | break; | |
337 | } | |
338 | /* signal the poll thread */ | |
339 | tmp2 = write(ctx->kconsumerd_poll_pipe[1], "4", 1); | |
340 | if (tmp2 < 0) { | |
341 | perror("write kconsumerd poll"); | |
342 | } | |
343 | } else { | |
344 | ERR("Didn't received any fd"); | |
345 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_ERROR_RECV_FD); | |
346 | ret = -1; | |
347 | goto end; | |
348 | } | |
349 | } | |
350 | ||
351 | end: | |
352 | return ret; | |
353 | } | |
354 | ||
355 | /* | |
356 | * Set the error socket. | |
357 | */ | |
358 | void lttng_kconsumerd_set_error_sock( | |
359 | struct lttng_kconsumerd_local_data *ctx, int sock) | |
360 | { | |
361 | ctx->kconsumerd_error_socket = sock; | |
362 | } | |
363 | ||
364 | /* | |
365 | * Set the command socket path. | |
366 | */ | |
367 | ||
368 | void lttng_kconsumerd_set_command_sock_path( | |
369 | struct lttng_kconsumerd_local_data *ctx, char *sock) | |
370 | { | |
371 | ctx->kconsumerd_command_sock_path = sock; | |
372 | } | |
1ce86c9a | 373 | |
92ab9ab6 JD |
374 | static void lttng_kconsumerd_sync_trace_file( |
375 | struct lttng_kconsumerd_fd *kconsumerd_fd, off_t orig_offset) | |
376 | { | |
377 | int outfd = kconsumerd_fd->out_fd; | |
378 | /* | |
379 | * This does a blocking write-and-wait on any page that belongs to the | |
380 | * subbuffer prior to the one we just wrote. | |
381 | * Don't care about error values, as these are just hints and ways to | |
382 | * limit the amount of page cache used. | |
383 | */ | |
384 | if (orig_offset >= kconsumerd_fd->max_sb_size) { | |
385 | sync_file_range(outfd, orig_offset - kconsumerd_fd->max_sb_size, | |
386 | kconsumerd_fd->max_sb_size, | |
387 | SYNC_FILE_RANGE_WAIT_BEFORE | |
388 | | SYNC_FILE_RANGE_WRITE | |
389 | | SYNC_FILE_RANGE_WAIT_AFTER); | |
390 | /* | |
391 | * Give hints to the kernel about how we access the file: | |
392 | * POSIX_FADV_DONTNEED : we won't re-access data in a near future after | |
393 | * we write it. | |
394 | * | |
395 | * We need to call fadvise again after the file grows because the | |
396 | * kernel does not seem to apply fadvise to non-existing parts of the | |
397 | * file. | |
398 | * | |
399 | * Call fadvise _after_ having waited for the page writeback to | |
400 | * complete because the dirty page writeback semantic is not well | |
401 | * defined. So it can be expected to lead to lower throughput in | |
402 | * streaming. | |
403 | */ | |
404 | posix_fadvise(outfd, orig_offset - kconsumerd_fd->max_sb_size, | |
405 | kconsumerd_fd->max_sb_size, POSIX_FADV_DONTNEED); | |
406 | } | |
407 | } | |
408 | ||
409 | ||
1ce86c9a | 410 | /* |
6533b585 | 411 | * Mmap the ring buffer, read it and write the data to the tracefile. |
1ce86c9a | 412 | * |
1ce86c9a JD |
413 | * Returns the number of bytes written |
414 | */ | |
6533b585 DG |
415 | int lttng_kconsumerd_on_read_subbuffer_mmap( |
416 | struct lttng_kconsumerd_local_data *ctx, | |
417 | struct lttng_kconsumerd_fd *kconsumerd_fd, unsigned long len) | |
1ce86c9a | 418 | { |
8b270bdb | 419 | unsigned long mmap_offset; |
1ce86c9a JD |
420 | long ret = 0; |
421 | off_t orig_offset = kconsumerd_fd->out_fd_offset; | |
422 | int fd = kconsumerd_fd->consumerd_fd; | |
423 | int outfd = kconsumerd_fd->out_fd; | |
424 | ||
1ce86c9a JD |
425 | /* get the offset inside the fd to mmap */ |
426 | ret = kernctl_get_mmap_read_offset(fd, &mmap_offset); | |
427 | if (ret != 0) { | |
428 | ret = errno; | |
429 | perror("kernctl_get_mmap_read_offset"); | |
430 | goto end; | |
431 | } | |
432 | ||
1ce86c9a | 433 | while (len > 0) { |
8b270bdb | 434 | ret = write(outfd, kconsumerd_fd->mmap_base + mmap_offset, len); |
1ce86c9a JD |
435 | if (ret >= len) { |
436 | len = 0; | |
437 | } else if (ret < 0) { | |
438 | ret = errno; | |
439 | perror("Error in file write"); | |
440 | goto end; | |
441 | } | |
442 | /* This won't block, but will start writeout asynchronously */ | |
443 | sync_file_range(outfd, kconsumerd_fd->out_fd_offset, ret, | |
444 | SYNC_FILE_RANGE_WRITE); | |
445 | kconsumerd_fd->out_fd_offset += ret; | |
446 | } | |
447 | ||
92ab9ab6 | 448 | lttng_kconsumerd_sync_trace_file(kconsumerd_fd, orig_offset); |
1ce86c9a | 449 | |
1ce86c9a JD |
450 | goto end; |
451 | ||
452 | end: | |
1ce86c9a JD |
453 | return ret; |
454 | } | |
455 | ||
456 | /* | |
1ce86c9a | 457 | * Splice the data from the ring buffer to the tracefile. |
6533b585 DG |
458 | * |
459 | * Returns the number of bytes spliced. | |
1ce86c9a | 460 | */ |
6533b585 DG |
461 | int lttng_kconsumerd_on_read_subbuffer_splice( |
462 | struct lttng_kconsumerd_local_data *ctx, | |
463 | struct lttng_kconsumerd_fd *kconsumerd_fd, unsigned long len) | |
1ce86c9a JD |
464 | { |
465 | long ret = 0; | |
466 | loff_t offset = 0; | |
467 | off_t orig_offset = kconsumerd_fd->out_fd_offset; | |
468 | int fd = kconsumerd_fd->consumerd_fd; | |
469 | int outfd = kconsumerd_fd->out_fd; | |
470 | ||
471 | while (len > 0) { | |
472 | DBG("splice chan to pipe offset %lu (fd : %d)", | |
473 | (unsigned long)offset, fd); | |
cb040cc1 | 474 | ret = splice(fd, &offset, ctx->kconsumerd_thread_pipe[1], NULL, len, |
1ce86c9a JD |
475 | SPLICE_F_MOVE | SPLICE_F_MORE); |
476 | DBG("splice chan to pipe ret %ld", ret); | |
477 | if (ret < 0) { | |
478 | ret = errno; | |
479 | perror("Error in relay splice"); | |
480 | goto splice_error; | |
481 | } | |
482 | ||
cb040cc1 | 483 | ret = splice(ctx->kconsumerd_thread_pipe[0], NULL, outfd, NULL, ret, |
1ce86c9a JD |
484 | SPLICE_F_MOVE | SPLICE_F_MORE); |
485 | DBG("splice pipe to file %ld", ret); | |
486 | if (ret < 0) { | |
487 | ret = errno; | |
488 | perror("Error in file splice"); | |
489 | goto splice_error; | |
490 | } | |
751667bd | 491 | len -= ret; |
1ce86c9a JD |
492 | /* This won't block, but will start writeout asynchronously */ |
493 | sync_file_range(outfd, kconsumerd_fd->out_fd_offset, ret, | |
494 | SYNC_FILE_RANGE_WRITE); | |
495 | kconsumerd_fd->out_fd_offset += ret; | |
496 | } | |
92ab9ab6 | 497 | lttng_kconsumerd_sync_trace_file(kconsumerd_fd, orig_offset); |
1ce86c9a | 498 | |
1ce86c9a JD |
499 | goto end; |
500 | ||
501 | splice_error: | |
502 | /* send the appropriate error description to sessiond */ | |
503 | switch(ret) { | |
504 | case EBADF: | |
6533b585 | 505 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_SPLICE_EBADF); |
1ce86c9a JD |
506 | break; |
507 | case EINVAL: | |
6533b585 | 508 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_SPLICE_EINVAL); |
1ce86c9a JD |
509 | break; |
510 | case ENOMEM: | |
6533b585 | 511 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_SPLICE_ENOMEM); |
1ce86c9a JD |
512 | break; |
513 | case ESPIPE: | |
6533b585 | 514 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_SPLICE_ESPIPE); |
1ce86c9a | 515 | break; |
1ce86c9a JD |
516 | } |
517 | ||
518 | end: | |
519 | return ret; | |
520 | } | |
521 | ||
92ab9ab6 JD |
522 | /* |
523 | * Take a snapshot for a specific fd | |
524 | * | |
525 | * Returns 0 on success, < 0 on error | |
526 | */ | |
527 | int lttng_kconsumerd_take_snapshot(struct lttng_kconsumerd_local_data *ctx, | |
528 | struct lttng_kconsumerd_fd *kconsumerd_fd) | |
529 | { | |
530 | int ret = 0; | |
531 | int infd = kconsumerd_fd->consumerd_fd; | |
532 | ||
533 | ret = kernctl_snapshot(infd); | |
534 | if (ret != 0) { | |
535 | ret = errno; | |
536 | perror("Getting sub-buffer snapshot."); | |
537 | } | |
538 | ||
539 | return ret; | |
540 | } | |
541 | ||
542 | /* | |
543 | * Get the produced position | |
544 | * | |
545 | * Returns 0 on success, < 0 on error | |
546 | */ | |
547 | int lttng_kconsumerd_get_produced_snapshot( | |
548 | struct lttng_kconsumerd_local_data *ctx, | |
549 | struct lttng_kconsumerd_fd *kconsumerd_fd, | |
550 | unsigned long *pos) | |
551 | { | |
552 | int ret; | |
553 | int infd = kconsumerd_fd->consumerd_fd; | |
554 | ||
555 | ret = kernctl_snapshot_get_produced(infd, pos); | |
556 | if (ret != 0) { | |
557 | ret = errno; | |
558 | perror("kernctl_snapshot_get_produced"); | |
559 | } | |
560 | ||
561 | return ret; | |
562 | } | |
563 | ||
4de84ad9 | 564 | /* |
6533b585 DG |
565 | * Poll on the should_quit pipe and the command socket return -1 on error and |
566 | * should exit, 0 if data is available on the command socket | |
4de84ad9 | 567 | */ |
6533b585 | 568 | int lttng_kconsumerd_poll_socket(struct pollfd *kconsumerd_sockpoll) |
4de84ad9 JD |
569 | { |
570 | int num_rdy; | |
571 | ||
572 | num_rdy = poll(kconsumerd_sockpoll, 2, -1); | |
573 | if (num_rdy == -1) { | |
574 | perror("Poll error"); | |
575 | goto exit; | |
576 | } | |
577 | if (kconsumerd_sockpoll[0].revents == POLLIN) { | |
578 | DBG("kconsumerd_should_quit wake up"); | |
579 | goto exit; | |
580 | } | |
581 | return 0; | |
582 | ||
583 | exit: | |
584 | return -1; | |
585 | } | |
586 | ||
1ce86c9a | 587 | /* |
6533b585 DG |
588 | * This thread polls the fds in the ltt_fd_list to consume the data and write |
589 | * it to tracefile if necessary. | |
1ce86c9a | 590 | */ |
6533b585 | 591 | void *lttng_kconsumerd_thread_poll_fds(void *data) |
1ce86c9a JD |
592 | { |
593 | int num_rdy, num_hup, high_prio, ret, i; | |
594 | struct pollfd *pollfd = NULL; | |
595 | /* local view of the fds */ | |
6533b585 | 596 | struct lttng_kconsumerd_fd **local_kconsumerd_fd = NULL; |
242cd187 | 597 | /* local view of kconsumerd_data.fds_count */ |
1ce86c9a JD |
598 | int nb_fd = 0; |
599 | char tmp; | |
600 | int tmp2; | |
6533b585 | 601 | struct lttng_kconsumerd_local_data *ctx = data; |
1ce86c9a | 602 | |
1ce86c9a | 603 | |
6533b585 | 604 | local_kconsumerd_fd = malloc(sizeof(struct lttng_kconsumerd_fd)); |
1ce86c9a JD |
605 | |
606 | while (1) { | |
607 | high_prio = 0; | |
608 | num_hup = 0; | |
609 | ||
610 | /* | |
611 | * the ltt_fd_list has been updated, we need to update our | |
612 | * local array as well | |
613 | */ | |
242cd187 MD |
614 | pthread_mutex_lock(&kconsumerd_data.lock); |
615 | if (kconsumerd_data.need_update) { | |
1ce86c9a JD |
616 | if (pollfd != NULL) { |
617 | free(pollfd); | |
618 | pollfd = NULL; | |
619 | } | |
620 | if (local_kconsumerd_fd != NULL) { | |
621 | free(local_kconsumerd_fd); | |
622 | local_kconsumerd_fd = NULL; | |
623 | } | |
0237248c | 624 | |
1ce86c9a | 625 | /* allocate for all fds + 1 for the kconsumerd_poll_pipe */ |
242cd187 | 626 | pollfd = malloc((kconsumerd_data.fds_count + 1) * sizeof(struct pollfd)); |
1ce86c9a JD |
627 | if (pollfd == NULL) { |
628 | perror("pollfd malloc"); | |
242cd187 | 629 | pthread_mutex_unlock(&kconsumerd_data.lock); |
1ce86c9a JD |
630 | goto end; |
631 | } | |
0237248c | 632 | |
1ce86c9a | 633 | /* allocate for all fds + 1 for the kconsumerd_poll_pipe */ |
242cd187 | 634 | local_kconsumerd_fd = malloc((kconsumerd_data.fds_count + 1) * |
6533b585 | 635 | sizeof(struct lttng_kconsumerd_fd)); |
1ce86c9a JD |
636 | if (local_kconsumerd_fd == NULL) { |
637 | perror("local_kconsumerd_fd malloc"); | |
242cd187 | 638 | pthread_mutex_unlock(&kconsumerd_data.lock); |
1ce86c9a JD |
639 | goto end; |
640 | } | |
cb040cc1 | 641 | ret = kconsumerd_update_poll_array(ctx, &pollfd, local_kconsumerd_fd); |
1ce86c9a JD |
642 | if (ret < 0) { |
643 | ERR("Error in allocating pollfd or local_outfds"); | |
6533b585 | 644 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_POLL_ERROR); |
242cd187 | 645 | pthread_mutex_unlock(&kconsumerd_data.lock); |
1ce86c9a JD |
646 | goto end; |
647 | } | |
648 | nb_fd = ret; | |
242cd187 | 649 | kconsumerd_data.need_update = 0; |
1ce86c9a | 650 | } |
242cd187 | 651 | pthread_mutex_unlock(&kconsumerd_data.lock); |
1ce86c9a JD |
652 | |
653 | /* poll on the array of fds */ | |
654 | DBG("polling on %d fd", nb_fd + 1); | |
655 | num_rdy = poll(pollfd, nb_fd + 1, kconsumerd_poll_timeout); | |
656 | DBG("poll num_rdy : %d", num_rdy); | |
657 | if (num_rdy == -1) { | |
658 | perror("Poll error"); | |
6533b585 | 659 | lttng_kconsumerd_send_error(ctx, KCONSUMERD_POLL_ERROR); |
1ce86c9a JD |
660 | goto end; |
661 | } else if (num_rdy == 0) { | |
662 | DBG("Polling thread timed out"); | |
663 | goto end; | |
664 | } | |
665 | ||
666 | /* No FDs and kconsumerd_quit, kconsumerd_cleanup the thread */ | |
667 | if (nb_fd == 0 && kconsumerd_quit == 1) { | |
668 | goto end; | |
669 | } | |
670 | ||
671 | /* | |
242cd187 MD |
672 | * If the kconsumerd_poll_pipe triggered poll go |
673 | * directly to the beginning of the loop to update the | |
674 | * array. We want to prioritize array update over | |
675 | * low-priority reads. | |
1ce86c9a | 676 | */ |
242cd187 | 677 | if (pollfd[nb_fd].revents == POLLIN) { |
1ce86c9a | 678 | DBG("kconsumerd_poll_pipe wake up"); |
cb040cc1 | 679 | tmp2 = read(ctx->kconsumerd_poll_pipe[0], &tmp, 1); |
f40799e8 DG |
680 | if (tmp2 < 0) { |
681 | perror("read kconsumerd poll"); | |
682 | } | |
1ce86c9a JD |
683 | continue; |
684 | } | |
685 | ||
686 | /* Take care of high priority channels first. */ | |
687 | for (i = 0; i < nb_fd; i++) { | |
688 | switch(pollfd[i].revents) { | |
689 | case POLLERR: | |
690 | ERR("Error returned in polling fd %d.", pollfd[i].fd); | |
691 | kconsumerd_del_fd(local_kconsumerd_fd[i]); | |
1ce86c9a JD |
692 | num_hup++; |
693 | break; | |
694 | case POLLHUP: | |
695 | DBG("Polling fd %d tells it has hung up.", pollfd[i].fd); | |
696 | kconsumerd_del_fd(local_kconsumerd_fd[i]); | |
1ce86c9a JD |
697 | num_hup++; |
698 | break; | |
699 | case POLLNVAL: | |
700 | ERR("Polling fd %d tells fd is not open.", pollfd[i].fd); | |
701 | kconsumerd_del_fd(local_kconsumerd_fd[i]); | |
1ce86c9a JD |
702 | num_hup++; |
703 | break; | |
704 | case POLLPRI: | |
705 | DBG("Urgent read on fd %d", pollfd[i].fd); | |
706 | high_prio = 1; | |
cb040cc1 | 707 | ret = ctx->on_buffer_ready(local_kconsumerd_fd[i]); |
1ce86c9a JD |
708 | /* it's ok to have an unavailable sub-buffer */ |
709 | if (ret == EAGAIN) { | |
710 | ret = 0; | |
711 | } | |
712 | break; | |
713 | } | |
714 | } | |
715 | ||
716 | /* If every buffer FD has hung up, we end the read loop here */ | |
717 | if (nb_fd > 0 && num_hup == nb_fd) { | |
718 | DBG("every buffer FD has hung up\n"); | |
719 | if (kconsumerd_quit == 1) { | |
720 | goto end; | |
721 | } | |
722 | continue; | |
723 | } | |
724 | ||
725 | /* Take care of low priority channels. */ | |
726 | if (high_prio == 0) { | |
727 | for (i = 0; i < nb_fd; i++) { | |
728 | if (pollfd[i].revents == POLLIN) { | |
729 | DBG("Normal read on fd %d", pollfd[i].fd); | |
cb040cc1 | 730 | ret = ctx->on_buffer_ready(local_kconsumerd_fd[i]); |
1ce86c9a JD |
731 | /* it's ok to have an unavailable subbuffer */ |
732 | if (ret == EAGAIN) { | |
733 | ret = 0; | |
734 | } | |
735 | } | |
736 | } | |
737 | } | |
738 | } | |
739 | end: | |
740 | DBG("polling thread exiting"); | |
741 | if (pollfd != NULL) { | |
742 | free(pollfd); | |
743 | pollfd = NULL; | |
744 | } | |
745 | if (local_kconsumerd_fd != NULL) { | |
746 | free(local_kconsumerd_fd); | |
747 | local_kconsumerd_fd = NULL; | |
748 | } | |
1ce86c9a JD |
749 | return NULL; |
750 | } | |
751 | ||
752 | /* | |
6533b585 | 753 | * Initialise the necessary environnement : |
cb040cc1 | 754 | * - create a new context |
4de84ad9 JD |
755 | * - create the poll_pipe |
756 | * - create the should_quit pipe (for signal handler) | |
cb040cc1 | 757 | * - create the thread pipe (for splice) |
6533b585 | 758 | * |
cb040cc1 JD |
759 | * Takes a function pointer as argument, this function is called when data is |
760 | * available on a buffer. This function is responsible to do the | |
761 | * kernctl_get_next_subbuf, read the data with mmap or splice depending on the | |
762 | * buffer configuration and then kernctl_put_next_subbuf at the end. | |
6533b585 | 763 | * |
cb040cc1 | 764 | * Returns a pointer to the new context or NULL on error. |
1ce86c9a | 765 | */ |
6533b585 | 766 | struct lttng_kconsumerd_local_data *lttng_kconsumerd_create( |
5348b470 JD |
767 | int (*buffer_ready)(struct lttng_kconsumerd_fd *kconsumerd_fd), |
768 | int (*recv_fd)(struct lttng_kconsumerd_fd *kconsumerd_fd), | |
769 | int (*update_fd)(int sessiond_fd, uint32_t state)) | |
1ce86c9a | 770 | { |
5348b470 | 771 | int ret, i; |
6533b585 | 772 | struct lttng_kconsumerd_local_data *ctx; |
4de84ad9 | 773 | |
6533b585 | 774 | ctx = malloc(sizeof(struct lttng_kconsumerd_local_data)); |
cb040cc1 JD |
775 | if (ctx == NULL) { |
776 | perror("allocating context"); | |
5348b470 | 777 | goto error; |
cb040cc1 JD |
778 | } |
779 | ||
5348b470 | 780 | /* assign the callbacks */ |
cb040cc1 | 781 | ctx->on_buffer_ready = buffer_ready; |
5348b470 JD |
782 | ctx->on_recv_fd = recv_fd; |
783 | ctx->on_update_fd = update_fd; | |
4de84ad9 | 784 | |
cb040cc1 | 785 | ret = pipe(ctx->kconsumerd_poll_pipe); |
4de84ad9 JD |
786 | if (ret < 0) { |
787 | perror("Error creating poll pipe"); | |
5348b470 | 788 | goto error_poll_pipe; |
4de84ad9 JD |
789 | } |
790 | ||
cb040cc1 | 791 | ret = pipe(ctx->kconsumerd_should_quit); |
4de84ad9 JD |
792 | if (ret < 0) { |
793 | perror("Error creating recv pipe"); | |
5348b470 | 794 | goto error_quit_pipe; |
cb040cc1 JD |
795 | } |
796 | ||
797 | ret = pipe(ctx->kconsumerd_thread_pipe); | |
798 | if (ret < 0) { | |
799 | perror("Error creating thread pipe"); | |
5348b470 | 800 | goto error_thread_pipe; |
4de84ad9 JD |
801 | } |
802 | ||
cb040cc1 | 803 | return ctx; |
5348b470 JD |
804 | |
805 | ||
806 | error_thread_pipe: | |
807 | for (i = 0; i < 2; i++) { | |
808 | int err; | |
809 | ||
810 | err = close(ctx->kconsumerd_should_quit[i]); | |
811 | assert(!err); | |
812 | } | |
813 | error_quit_pipe: | |
814 | for (i = 0; i < 2; i++) { | |
815 | int err; | |
816 | ||
817 | err = close(ctx->kconsumerd_poll_pipe[i]); | |
818 | assert(!err); | |
819 | } | |
820 | error_poll_pipe: | |
821 | free(ctx); | |
822 | error: | |
823 | return NULL; | |
cb040cc1 JD |
824 | } |
825 | ||
826 | /* | |
6533b585 | 827 | * Close all fds associated with the instance and free the context. |
cb040cc1 | 828 | */ |
6533b585 | 829 | void lttng_kconsumerd_destroy(struct lttng_kconsumerd_local_data *ctx) |
cb040cc1 JD |
830 | { |
831 | close(ctx->kconsumerd_error_socket); | |
832 | close(ctx->kconsumerd_thread_pipe[0]); | |
833 | close(ctx->kconsumerd_thread_pipe[1]); | |
834 | close(ctx->kconsumerd_poll_pipe[0]); | |
835 | close(ctx->kconsumerd_poll_pipe[1]); | |
836 | close(ctx->kconsumerd_should_quit[0]); | |
837 | close(ctx->kconsumerd_should_quit[1]); | |
838 | unlink(ctx->kconsumerd_command_sock_path); | |
839 | free(ctx); | |
840 | ctx = NULL; | |
1ce86c9a JD |
841 | } |
842 | ||
843 | /* | |
6533b585 DG |
844 | * This thread listens on the consumerd socket and receives the file |
845 | * descriptors from the session daemon. | |
1ce86c9a | 846 | */ |
6533b585 | 847 | void *lttng_kconsumerd_thread_receive_fds(void *data) |
1ce86c9a JD |
848 | { |
849 | int sock, client_socket, ret; | |
850 | struct lttcomm_kconsumerd_header tmp; | |
4de84ad9 | 851 | /* |
6533b585 DG |
852 | * structure to poll for incoming data on communication socket avoids |
853 | * making blocking sockets. | |
4de84ad9 JD |
854 | */ |
855 | struct pollfd kconsumerd_sockpoll[2]; | |
6533b585 | 856 | struct lttng_kconsumerd_local_data *ctx = data; |
4de84ad9 | 857 | |
1ce86c9a | 858 | |
cb040cc1 JD |
859 | DBG("Creating command socket %s", ctx->kconsumerd_command_sock_path); |
860 | unlink(ctx->kconsumerd_command_sock_path); | |
861 | client_socket = lttcomm_create_unix_sock(ctx->kconsumerd_command_sock_path); | |
1ce86c9a JD |
862 | if (client_socket < 0) { |
863 | ERR("Cannot create command socket"); | |
864 | goto end; | |
865 | } | |
866 | ||
867 | ret = lttcomm_listen_unix_sock(client_socket); | |
868 | if (ret < 0) { | |
869 | goto end; | |
870 | } | |
871 | ||
872 | DBG("Sending ready command to ltt-sessiond"); | |
6533b585 | 873 | ret = lttng_kconsumerd_send_error(ctx, KCONSUMERD_COMMAND_SOCK_READY); |
1ce86c9a JD |
874 | if (ret < 0) { |
875 | ERR("Error sending ready command to ltt-sessiond"); | |
876 | goto end; | |
877 | } | |
878 | ||
4de84ad9 JD |
879 | ret = fcntl(client_socket, F_SETFL, O_NONBLOCK); |
880 | if (ret < 0) { | |
881 | perror("fcntl O_NONBLOCK"); | |
882 | goto end; | |
883 | } | |
884 | ||
885 | /* prepare the FDs to poll : to client socket and the should_quit pipe */ | |
cb040cc1 | 886 | kconsumerd_sockpoll[0].fd = ctx->kconsumerd_should_quit[0]; |
4de84ad9 JD |
887 | kconsumerd_sockpoll[0].events = POLLIN | POLLPRI; |
888 | kconsumerd_sockpoll[1].fd = client_socket; | |
889 | kconsumerd_sockpoll[1].events = POLLIN | POLLPRI; | |
890 | ||
6533b585 | 891 | if (lttng_kconsumerd_poll_socket(kconsumerd_sockpoll) < 0) { |
4de84ad9 JD |
892 | goto end; |
893 | } | |
894 | DBG("Connection on client_socket"); | |
895 | ||
1ce86c9a JD |
896 | /* Blocking call, waiting for transmission */ |
897 | sock = lttcomm_accept_unix_sock(client_socket); | |
898 | if (sock <= 0) { | |
899 | WARN("On accept"); | |
900 | goto end; | |
901 | } | |
4de84ad9 JD |
902 | ret = fcntl(sock, F_SETFL, O_NONBLOCK); |
903 | if (ret < 0) { | |
904 | perror("fcntl O_NONBLOCK"); | |
905 | goto end; | |
906 | } | |
907 | ||
908 | /* update the polling structure to poll on the established socket */ | |
909 | kconsumerd_sockpoll[1].fd = sock; | |
910 | kconsumerd_sockpoll[1].events = POLLIN | POLLPRI; | |
911 | ||
1ce86c9a | 912 | while (1) { |
6533b585 | 913 | if (lttng_kconsumerd_poll_socket(kconsumerd_sockpoll) < 0) { |
4de84ad9 JD |
914 | goto end; |
915 | } | |
916 | DBG("Incoming fds on sock"); | |
917 | ||
1ce86c9a JD |
918 | /* We first get the number of fd we are about to receive */ |
919 | ret = lttcomm_recv_unix_sock(sock, &tmp, | |
920 | sizeof(struct lttcomm_kconsumerd_header)); | |
921 | if (ret <= 0) { | |
922 | ERR("Communication interrupted on command socket"); | |
923 | goto end; | |
924 | } | |
925 | if (tmp.cmd_type == STOP) { | |
926 | DBG("Received STOP command"); | |
927 | goto end; | |
928 | } | |
3dcd2721 MD |
929 | if (kconsumerd_quit) { |
930 | DBG("kconsumerd_thread_receive_fds received quit from signal"); | |
931 | goto end; | |
932 | } | |
4de84ad9 | 933 | |
1ce86c9a | 934 | /* we received a command to add or update fds */ |
cb040cc1 | 935 | ret = kconsumerd_consumerd_recv_fd(ctx, sock, kconsumerd_sockpoll, |
4de84ad9 | 936 | tmp.payload_size, tmp.cmd_type); |
8b270bdb | 937 | if (ret < 0) { |
1ce86c9a JD |
938 | ERR("Receiving the FD, exiting"); |
939 | goto end; | |
940 | } | |
4de84ad9 | 941 | DBG("received fds on sock"); |
1ce86c9a JD |
942 | } |
943 | ||
944 | end: | |
945 | DBG("kconsumerd_thread_receive_fds exiting"); | |
946 | ||
947 | /* | |
948 | * when all fds have hung up, the polling thread | |
949 | * can exit cleanly | |
950 | */ | |
951 | kconsumerd_quit = 1; | |
952 | ||
953 | /* | |
954 | * 2s of grace period, if no polling events occur during | |
955 | * this period, the polling thread will exit even if there | |
956 | * are still open FDs (should not happen, but safety mechanism). | |
957 | */ | |
6533b585 | 958 | kconsumerd_poll_timeout = LTTNG_KCONSUMERD_POLL_GRACE_PERIOD; |
1ce86c9a JD |
959 | |
960 | /* wake up the polling thread */ | |
cb040cc1 | 961 | ret = write(ctx->kconsumerd_poll_pipe[1], "4", 1); |
1ce86c9a JD |
962 | if (ret < 0) { |
963 | perror("poll pipe write"); | |
964 | } | |
965 | return NULL; | |
966 | } | |
967 | ||
968 | /* | |
6533b585 DG |
969 | * Close all the tracefiles and stream fds, should be called when all instances |
970 | * are destroyed. | |
1ce86c9a | 971 | */ |
6533b585 | 972 | void lttng_kconsumerd_cleanup(void) |
1ce86c9a | 973 | { |
6533b585 | 974 | struct lttng_kconsumerd_fd *iter, *tmp; |
1ce86c9a | 975 | |
3dcd2721 MD |
976 | /* |
977 | * close all outfd. Called when there are no more threads | |
978 | * running (after joining on the threads), no need to protect | |
979 | * list iteration with mutex. | |
980 | */ | |
6533b585 DG |
981 | cds_list_for_each_entry_safe(iter, tmp, |
982 | &kconsumerd_data.fd_list.head, list) { | |
1ce86c9a JD |
983 | kconsumerd_del_fd(iter); |
984 | } | |
985 | } | |
986 | ||
3dcd2721 MD |
987 | /* |
988 | * Called from signal handler. | |
989 | */ | |
6533b585 | 990 | void lttng_kconsumerd_should_exit(struct lttng_kconsumerd_local_data *ctx) |
3dcd2721 | 991 | { |
4de84ad9 | 992 | int ret; |
3dcd2721 | 993 | kconsumerd_quit = 1; |
cb040cc1 | 994 | ret = write(ctx->kconsumerd_should_quit[1], "4", 1); |
f40799e8 DG |
995 | if (ret < 0) { |
996 | perror("write kconsumerd quit"); | |
997 | } | |
3dcd2721 MD |
998 | } |
999 | ||
1ce86c9a | 1000 | /* |
6533b585 | 1001 | * Send return code to the session daemon. |
1ce86c9a | 1002 | */ |
6533b585 DG |
1003 | int lttng_kconsumerd_send_error( |
1004 | struct lttng_kconsumerd_local_data *ctx, int cmd) | |
1ce86c9a | 1005 | { |
cb040cc1 JD |
1006 | if (ctx->kconsumerd_error_socket > 0) { |
1007 | return lttcomm_send_unix_sock(ctx->kconsumerd_error_socket, &cmd, | |
1ce86c9a JD |
1008 | sizeof(enum lttcomm_sessiond_command)); |
1009 | } | |
1010 | ||
1011 | return 0; | |
1012 | } |