Commit | Line | Data |
---|---|---|
20fe2104 DG |
1 | /* |
2 | * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca> | |
3 | * | |
d14d33bf AM |
4 | * This program is free software; you can redistribute it and/or modify |
5 | * it under the terms of the GNU General Public License, version 2 only, | |
6 | * as published by the Free Software Foundation. | |
20fe2104 DG |
7 | * |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | * | |
d14d33bf AM |
13 | * You should have received a copy of the GNU General Public License along |
14 | * with this program; if not, write to the Free Software Foundation, Inc., | |
15 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
20fe2104 DG |
16 | */ |
17 | ||
6c1c0768 | 18 | #define _LGPL_SOURCE |
7b395890 | 19 | #include <fcntl.h> |
20fe2104 DG |
20 | #include <stdlib.h> |
21 | #include <stdio.h> | |
f34daff7 | 22 | #include <string.h> |
8c0faa1d | 23 | #include <unistd.h> |
77c7c900 | 24 | #include <inttypes.h> |
20fe2104 | 25 | |
990570ed | 26 | #include <common/common.h> |
db758600 | 27 | #include <common/kernel-ctl/kernel-ctl.h> |
c052142c | 28 | #include <common/kernel-ctl/kernel-ioctl.h> |
42224349 | 29 | #include <common/sessiond-comm/sessiond-comm.h> |
1e307fab | 30 | |
2f77fc4b | 31 | #include "consumer.h" |
4771f025 | 32 | #include "kernel.h" |
6dc3064a | 33 | #include "kernel-consumer.h" |
096102bd | 34 | #include "kern-modules.h" |
834978fd | 35 | #include "utils.h" |
6e0be6cc | 36 | #include "rotation-thread.h" |
20fe2104 | 37 | |
d65106b1 | 38 | /* |
050349bb | 39 | * Add context on a kernel channel. |
df3c77c8 JG |
40 | * |
41 | * Assumes the ownership of ctx. | |
d65106b1 DG |
42 | */ |
43 | int kernel_add_channel_context(struct ltt_kernel_channel *chan, | |
645328ae | 44 | struct ltt_kernel_context *ctx) |
d65106b1 DG |
45 | { |
46 | int ret; | |
47 | ||
0525e9ae DG |
48 | assert(chan); |
49 | assert(ctx); | |
50 | ||
d65106b1 | 51 | DBG("Adding context to channel %s", chan->channel->name); |
645328ae | 52 | ret = kernctl_add_context(chan->fd, &ctx->ctx); |
d65106b1 | 53 | if (ret < 0) { |
32af2c95 | 54 | switch (-ret) { |
1ae5e83e JD |
55 | case ENOSYS: |
56 | /* Exists but not available for this kernel */ | |
57 | ret = LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE; | |
58 | goto error; | |
59 | case EEXIST: | |
b579acd9 DG |
60 | /* If EEXIST, we just ignore the error */ |
61 | ret = 0; | |
1ae5e83e JD |
62 | goto end; |
63 | default: | |
64 | PERROR("add context ioctl"); | |
65 | ret = LTTNG_ERR_KERN_CONTEXT_FAIL; | |
66 | goto error; | |
b579acd9 | 67 | } |
d65106b1 | 68 | } |
21ed98c1 | 69 | ret = 0; |
d65106b1 | 70 | |
1ae5e83e | 71 | end: |
645328ae | 72 | cds_list_add_tail(&ctx->list, &chan->ctx_list); |
ba985c3a | 73 | ctx->in_list = true; |
df3c77c8 | 74 | ctx = NULL; |
d65106b1 | 75 | error: |
df3c77c8 JG |
76 | if (ctx) { |
77 | trace_kernel_destroy_context(ctx); | |
78 | } | |
d65106b1 DG |
79 | return ret; |
80 | } | |
81 | ||
20fe2104 | 82 | /* |
050349bb DG |
83 | * Create a new kernel session, register it to the kernel tracer and add it to |
84 | * the session daemon session. | |
20fe2104 | 85 | */ |
8c0faa1d | 86 | int kernel_create_session(struct ltt_session *session, int tracer_fd) |
20fe2104 DG |
87 | { |
88 | int ret; | |
89 | struct ltt_kernel_session *lks; | |
90 | ||
0525e9ae DG |
91 | assert(session); |
92 | ||
54012638 | 93 | /* Allocate data structure */ |
dec56f6c | 94 | lks = trace_kernel_create_session(); |
20fe2104 | 95 | if (lks == NULL) { |
54012638 | 96 | ret = -1; |
20fe2104 DG |
97 | goto error; |
98 | } | |
99 | ||
54012638 | 100 | /* Kernel tracer session creation */ |
20fe2104 DG |
101 | ret = kernctl_create_session(tracer_fd); |
102 | if (ret < 0) { | |
df0f840b | 103 | PERROR("ioctl kernel create session"); |
20fe2104 DG |
104 | goto error; |
105 | } | |
106 | ||
20fe2104 | 107 | lks->fd = ret; |
7b395890 DG |
108 | /* Prevent fd duplication after execlp() */ |
109 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
110 | if (ret < 0) { | |
df0f840b | 111 | PERROR("fcntl session fd"); |
7b395890 DG |
112 | } |
113 | ||
53632229 | 114 | lks->id = session->id; |
3bd1e081 | 115 | lks->consumer_fds_sent = 0; |
8c0faa1d | 116 | session->kernel_session = lks; |
8c0faa1d DG |
117 | |
118 | DBG("Kernel session created (fd: %d)", lks->fd); | |
20fe2104 DG |
119 | |
120 | return 0; | |
121 | ||
122 | error: | |
5f62c685 DG |
123 | if (lks) { |
124 | trace_kernel_destroy_session(lks); | |
125 | } | |
20fe2104 DG |
126 | return ret; |
127 | } | |
128 | ||
129 | /* | |
050349bb DG |
130 | * Create a kernel channel, register it to the kernel tracer and add it to the |
131 | * kernel session. | |
20fe2104 | 132 | */ |
050349bb | 133 | int kernel_create_channel(struct ltt_kernel_session *session, |
fdd9eb17 | 134 | struct lttng_channel *chan) |
20fe2104 DG |
135 | { |
136 | int ret; | |
137 | struct ltt_kernel_channel *lkc; | |
20fe2104 | 138 | |
0525e9ae DG |
139 | assert(session); |
140 | assert(chan); | |
0525e9ae | 141 | |
54012638 | 142 | /* Allocate kernel channel */ |
fdd9eb17 | 143 | lkc = trace_kernel_create_channel(chan); |
54012638 | 144 | if (lkc == NULL) { |
20fe2104 DG |
145 | goto error; |
146 | } | |
147 | ||
ecc48a90 | 148 | DBG3("Kernel create channel %s with attr: %d, %" PRIu64 ", %" PRIu64 ", %u, %u, %d, %d", |
fdd9eb17 | 149 | chan->name, lkc->channel->attr.overwrite, |
173af62f DG |
150 | lkc->channel->attr.subbuf_size, lkc->channel->attr.num_subbuf, |
151 | lkc->channel->attr.switch_timer_interval, lkc->channel->attr.read_timer_interval, | |
ecc48a90 | 152 | lkc->channel->attr.live_timer_interval, lkc->channel->attr.output); |
173af62f | 153 | |
54012638 | 154 | /* Kernel tracer channel creation */ |
f3ed775e | 155 | ret = kernctl_create_channel(session->fd, &lkc->channel->attr); |
20fe2104 | 156 | if (ret < 0) { |
df0f840b | 157 | PERROR("ioctl kernel create channel"); |
20fe2104 DG |
158 | goto error; |
159 | } | |
160 | ||
54012638 | 161 | /* Setup the channel fd */ |
20fe2104 | 162 | lkc->fd = ret; |
7b395890 DG |
163 | /* Prevent fd duplication after execlp() */ |
164 | ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC); | |
165 | if (ret < 0) { | |
df0f840b | 166 | PERROR("fcntl session fd"); |
7b395890 DG |
167 | } |
168 | ||
54012638 | 169 | /* Add channel to session */ |
8c0faa1d DG |
170 | cds_list_add(&lkc->list, &session->channel_list.head); |
171 | session->channel_count++; | |
fb5f35b6 | 172 | lkc->session = session; |
20fe2104 | 173 | |
00e2e675 | 174 | DBG("Kernel channel %s created (fd: %d)", lkc->channel->name, lkc->fd); |
20fe2104 DG |
175 | |
176 | return 0; | |
177 | ||
178 | error: | |
5f62c685 DG |
179 | if (lkc) { |
180 | free(lkc->channel); | |
181 | free(lkc); | |
182 | } | |
54012638 | 183 | return -1; |
20fe2104 | 184 | } |
f34daff7 DG |
185 | |
186 | /* | |
050349bb DG |
187 | * Create a kernel event, enable it to the kernel tracer and add it to the |
188 | * channel event list of the kernel session. | |
49d21f93 | 189 | * We own filter_expression and filter. |
f34daff7 | 190 | */ |
050349bb | 191 | int kernel_create_event(struct lttng_event *ev, |
00a62084 MD |
192 | struct ltt_kernel_channel *channel, |
193 | char *filter_expression, | |
194 | struct lttng_filter_bytecode *filter) | |
f34daff7 DG |
195 | { |
196 | int ret; | |
197 | struct ltt_kernel_event *event; | |
f34daff7 | 198 | |
0525e9ae DG |
199 | assert(ev); |
200 | assert(channel); | |
201 | ||
a969e101 | 202 | /* We pass ownership of filter_expression and filter */ |
00a62084 MD |
203 | event = trace_kernel_create_event(ev, filter_expression, |
204 | filter); | |
54012638 | 205 | if (event == NULL) { |
d87bfb32 | 206 | ret = -1; |
f34daff7 DG |
207 | goto error; |
208 | } | |
209 | ||
f3ed775e DG |
210 | ret = kernctl_create_event(channel->fd, event->event); |
211 | if (ret < 0) { | |
32af2c95 | 212 | switch (-ret) { |
bd29c13d DG |
213 | case EEXIST: |
214 | break; | |
215 | case ENOSYS: | |
216 | WARN("Event type not implemented"); | |
217 | break; | |
8197a339 DG |
218 | case ENOENT: |
219 | WARN("Event %s not found!", ev->name); | |
220 | break; | |
bd29c13d | 221 | default: |
d87bfb32 DG |
222 | PERROR("create event ioctl"); |
223 | } | |
e953ef25 | 224 | goto free_event; |
8c0faa1d | 225 | } |
f34daff7 | 226 | |
d0ae4ea8 | 227 | event->type = ev->type; |
f3ed775e | 228 | event->fd = ret; |
7b395890 DG |
229 | /* Prevent fd duplication after execlp() */ |
230 | ret = fcntl(event->fd, F_SETFD, FD_CLOEXEC); | |
231 | if (ret < 0) { | |
df0f840b | 232 | PERROR("fcntl session fd"); |
7b395890 DG |
233 | } |
234 | ||
00a62084 MD |
235 | if (filter) { |
236 | ret = kernctl_filter(event->fd, filter); | |
237 | if (ret) { | |
238 | goto filter_error; | |
239 | } | |
240 | } | |
241 | ||
242 | ret = kernctl_enable(event->fd); | |
243 | if (ret < 0) { | |
32af2c95 | 244 | switch (-ret) { |
00a62084 MD |
245 | case EEXIST: |
246 | ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
247 | break; | |
248 | default: | |
249 | PERROR("enable kernel event"); | |
250 | break; | |
251 | } | |
252 | goto enable_error; | |
253 | } | |
254 | ||
f3ed775e DG |
255 | /* Add event to event list */ |
256 | cds_list_add(&event->list, &channel->events_list.head); | |
cbbbb275 DG |
257 | channel->event_count++; |
258 | ||
e953ef25 DG |
259 | DBG("Event %s created (fd: %d)", ev->name, event->fd); |
260 | ||
261 | return 0; | |
262 | ||
00a62084 MD |
263 | enable_error: |
264 | filter_error: | |
265 | { | |
266 | int closeret; | |
267 | ||
268 | closeret = close(event->fd); | |
269 | if (closeret) { | |
270 | PERROR("close event fd"); | |
271 | } | |
272 | } | |
e953ef25 DG |
273 | free_event: |
274 | free(event); | |
275 | error: | |
d87bfb32 | 276 | return ret; |
e953ef25 DG |
277 | } |
278 | ||
26cc6b4e | 279 | /* |
050349bb | 280 | * Disable a kernel channel. |
26cc6b4e DG |
281 | */ |
282 | int kernel_disable_channel(struct ltt_kernel_channel *chan) | |
283 | { | |
284 | int ret; | |
285 | ||
0525e9ae DG |
286 | assert(chan); |
287 | ||
26cc6b4e DG |
288 | ret = kernctl_disable(chan->fd); |
289 | if (ret < 0) { | |
df0f840b | 290 | PERROR("disable chan ioctl"); |
26cc6b4e DG |
291 | goto error; |
292 | } | |
293 | ||
294 | chan->enabled = 0; | |
295 | DBG("Kernel channel %s disabled (fd: %d)", chan->channel->name, chan->fd); | |
296 | ||
297 | return 0; | |
298 | ||
299 | error: | |
300 | return ret; | |
301 | } | |
302 | ||
d36b8583 | 303 | /* |
050349bb | 304 | * Enable a kernel channel. |
d36b8583 DG |
305 | */ |
306 | int kernel_enable_channel(struct ltt_kernel_channel *chan) | |
307 | { | |
308 | int ret; | |
309 | ||
0525e9ae DG |
310 | assert(chan); |
311 | ||
d36b8583 | 312 | ret = kernctl_enable(chan->fd); |
32af2c95 | 313 | if (ret < 0 && ret != -EEXIST) { |
df0f840b | 314 | PERROR("Enable kernel chan"); |
d36b8583 DG |
315 | goto error; |
316 | } | |
317 | ||
318 | chan->enabled = 1; | |
319 | DBG("Kernel channel %s enabled (fd: %d)", chan->channel->name, chan->fd); | |
320 | ||
321 | return 0; | |
322 | ||
323 | error: | |
324 | return ret; | |
325 | } | |
326 | ||
19e70852 | 327 | /* |
050349bb | 328 | * Enable a kernel event. |
19e70852 DG |
329 | */ |
330 | int kernel_enable_event(struct ltt_kernel_event *event) | |
331 | { | |
332 | int ret; | |
333 | ||
0525e9ae DG |
334 | assert(event); |
335 | ||
19e70852 | 336 | ret = kernctl_enable(event->fd); |
42224349 | 337 | if (ret < 0) { |
32af2c95 | 338 | switch (-ret) { |
42224349 | 339 | case EEXIST: |
f73fabfd | 340 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
341 | break; |
342 | default: | |
343 | PERROR("enable kernel event"); | |
344 | break; | |
345 | } | |
19e70852 DG |
346 | goto error; |
347 | } | |
348 | ||
349 | event->enabled = 1; | |
350 | DBG("Kernel event %s enabled (fd: %d)", event->event->name, event->fd); | |
351 | ||
352 | return 0; | |
353 | ||
354 | error: | |
d36b8583 | 355 | return ret; |
19e70852 DG |
356 | } |
357 | ||
e953ef25 | 358 | /* |
050349bb | 359 | * Disable a kernel event. |
e953ef25 | 360 | */ |
19e70852 | 361 | int kernel_disable_event(struct ltt_kernel_event *event) |
e953ef25 DG |
362 | { |
363 | int ret; | |
19e70852 | 364 | |
0525e9ae DG |
365 | assert(event); |
366 | ||
19e70852 | 367 | ret = kernctl_disable(event->fd); |
42224349 | 368 | if (ret < 0) { |
32af2c95 | 369 | switch (-ret) { |
42224349 | 370 | case EEXIST: |
f73fabfd | 371 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
372 | break; |
373 | default: | |
374 | PERROR("disable kernel event"); | |
375 | break; | |
376 | } | |
19e70852 | 377 | goto error; |
e953ef25 | 378 | } |
f3ed775e | 379 | |
19e70852 DG |
380 | event->enabled = 0; |
381 | DBG("Kernel event %s disabled (fd: %d)", event->event->name, event->fd); | |
382 | ||
f34daff7 DG |
383 | return 0; |
384 | ||
385 | error: | |
d36b8583 | 386 | return ret; |
f34daff7 | 387 | } |
aaf26714 | 388 | |
6e911cad | 389 | |
ccf10263 MD |
390 | int kernel_track_pid(struct ltt_kernel_session *session, int pid) |
391 | { | |
7c493d31 MD |
392 | int ret; |
393 | ||
ccf10263 MD |
394 | DBG("Kernel track PID %d for session id %" PRIu64 ".", |
395 | pid, session->id); | |
7c493d31 MD |
396 | ret = kernctl_track_pid(session->fd, pid); |
397 | if (!ret) { | |
398 | return LTTNG_OK; | |
399 | } | |
32af2c95 | 400 | switch (-ret) { |
7c493d31 MD |
401 | case EINVAL: |
402 | return LTTNG_ERR_INVALID; | |
403 | case ENOMEM: | |
404 | return LTTNG_ERR_NOMEM; | |
405 | case EEXIST: | |
406 | return LTTNG_ERR_PID_TRACKED; | |
407 | default: | |
408 | return LTTNG_ERR_UNK; | |
409 | } | |
ccf10263 MD |
410 | } |
411 | ||
412 | int kernel_untrack_pid(struct ltt_kernel_session *session, int pid) | |
413 | { | |
7c493d31 MD |
414 | int ret; |
415 | ||
ccf10263 MD |
416 | DBG("Kernel untrack PID %d for session id %" PRIu64 ".", |
417 | pid, session->id); | |
7c493d31 MD |
418 | ret = kernctl_untrack_pid(session->fd, pid); |
419 | if (!ret) { | |
420 | return LTTNG_OK; | |
421 | } | |
32af2c95 | 422 | switch (-ret) { |
7c493d31 MD |
423 | case EINVAL: |
424 | return LTTNG_ERR_INVALID; | |
425 | case ENOMEM: | |
426 | return LTTNG_ERR_NOMEM; | |
427 | case ENOENT: | |
428 | return LTTNG_ERR_PID_NOT_TRACKED; | |
429 | default: | |
430 | return LTTNG_ERR_UNK; | |
431 | } | |
ccf10263 MD |
432 | } |
433 | ||
a5dfbb9d MD |
434 | ssize_t kernel_list_tracker_pids(struct ltt_kernel_session *session, |
435 | int **_pids) | |
436 | { | |
437 | int fd, ret; | |
438 | int pid; | |
439 | ssize_t nbmem, count = 0; | |
440 | FILE *fp; | |
441 | int *pids; | |
442 | ||
443 | fd = kernctl_list_tracker_pids(session->fd); | |
444 | if (fd < 0) { | |
445 | PERROR("kernel tracker pids list"); | |
446 | goto error; | |
447 | } | |
448 | ||
449 | fp = fdopen(fd, "r"); | |
450 | if (fp == NULL) { | |
451 | PERROR("kernel tracker pids list fdopen"); | |
452 | goto error_fp; | |
453 | } | |
454 | ||
455 | nbmem = KERNEL_TRACKER_PIDS_INIT_LIST_SIZE; | |
456 | pids = zmalloc(sizeof(*pids) * nbmem); | |
457 | if (pids == NULL) { | |
458 | PERROR("alloc list pids"); | |
459 | count = -ENOMEM; | |
460 | goto end; | |
461 | } | |
462 | ||
463 | while (fscanf(fp, "process { pid = %u; };\n", &pid) == 1) { | |
464 | if (count >= nbmem) { | |
465 | int *new_pids; | |
466 | size_t new_nbmem; | |
467 | ||
468 | new_nbmem = nbmem << 1; | |
469 | DBG("Reallocating pids list from %zu to %zu entries", | |
470 | nbmem, new_nbmem); | |
471 | new_pids = realloc(pids, new_nbmem * sizeof(*new_pids)); | |
472 | if (new_pids == NULL) { | |
473 | PERROR("realloc list events"); | |
474 | free(pids); | |
475 | count = -ENOMEM; | |
476 | goto end; | |
477 | } | |
478 | /* Zero the new memory */ | |
479 | memset(new_pids + nbmem, 0, | |
480 | (new_nbmem - nbmem) * sizeof(*new_pids)); | |
481 | nbmem = new_nbmem; | |
482 | pids = new_pids; | |
483 | } | |
484 | pids[count++] = pid; | |
485 | } | |
486 | ||
487 | *_pids = pids; | |
488 | DBG("Kernel list tracker pids done (%zd pids)", count); | |
489 | end: | |
490 | ret = fclose(fp); /* closes both fp and fd */ | |
491 | if (ret) { | |
492 | PERROR("fclose"); | |
493 | } | |
494 | return count; | |
495 | ||
496 | error_fp: | |
497 | ret = close(fd); | |
498 | if (ret) { | |
499 | PERROR("close"); | |
500 | } | |
501 | error: | |
502 | return -1; | |
503 | } | |
504 | ||
aaf26714 | 505 | /* |
050349bb DG |
506 | * Create kernel metadata, open from the kernel tracer and add it to the |
507 | * kernel session. | |
aaf26714 | 508 | */ |
a4b92340 | 509 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
510 | { |
511 | int ret; | |
74024a21 | 512 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 513 | |
0525e9ae DG |
514 | assert(session); |
515 | ||
54012638 | 516 | /* Allocate kernel metadata */ |
a4b92340 | 517 | lkm = trace_kernel_create_metadata(); |
54012638 | 518 | if (lkm == NULL) { |
aaf26714 DG |
519 | goto error; |
520 | } | |
521 | ||
54012638 | 522 | /* Kernel tracer metadata creation */ |
f3ed775e | 523 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 524 | if (ret < 0) { |
74024a21 | 525 | goto error_open; |
aaf26714 DG |
526 | } |
527 | ||
8c0faa1d | 528 | lkm->fd = ret; |
7b395890 DG |
529 | /* Prevent fd duplication after execlp() */ |
530 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
531 | if (ret < 0) { | |
df0f840b | 532 | PERROR("fcntl session fd"); |
7b395890 DG |
533 | } |
534 | ||
aaf26714 | 535 | session->metadata = lkm; |
8c0faa1d | 536 | |
00e2e675 | 537 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
538 | |
539 | return 0; | |
540 | ||
74024a21 DG |
541 | error_open: |
542 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 543 | error: |
54012638 | 544 | return -1; |
8c0faa1d DG |
545 | } |
546 | ||
547 | /* | |
050349bb | 548 | * Start tracing session. |
8c0faa1d DG |
549 | */ |
550 | int kernel_start_session(struct ltt_kernel_session *session) | |
551 | { | |
552 | int ret; | |
553 | ||
0525e9ae DG |
554 | assert(session); |
555 | ||
8c0faa1d DG |
556 | ret = kernctl_start_session(session->fd); |
557 | if (ret < 0) { | |
df0f840b | 558 | PERROR("ioctl start session"); |
8c0faa1d DG |
559 | goto error; |
560 | } | |
561 | ||
562 | DBG("Kernel session started"); | |
563 | ||
564 | return 0; | |
565 | ||
566 | error: | |
567 | return ret; | |
568 | } | |
569 | ||
f3ed775e | 570 | /* |
050349bb | 571 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e DG |
572 | */ |
573 | void kernel_wait_quiescent(int fd) | |
574 | { | |
575 | int ret; | |
576 | ||
577 | DBG("Kernel quiescent wait on %d", fd); | |
578 | ||
579 | ret = kernctl_wait_quiescent(fd); | |
580 | if (ret < 0) { | |
df0f840b | 581 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
582 | ERR("Kernel quiescent wait failed"); |
583 | } | |
584 | } | |
585 | ||
586 | /* | |
f3ed775e DG |
587 | * Force flush buffer of metadata. |
588 | */ | |
589 | int kernel_metadata_flush_buffer(int fd) | |
590 | { | |
591 | int ret; | |
592 | ||
169d2cb7 DG |
593 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
594 | ||
f3ed775e DG |
595 | ret = kernctl_buffer_flush(fd); |
596 | if (ret < 0) { | |
00e2e675 | 597 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
598 | } |
599 | ||
600 | return 0; | |
601 | } | |
602 | ||
603 | /* | |
050349bb | 604 | * Force flush buffer for channel. |
f3ed775e DG |
605 | */ |
606 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
607 | { | |
608 | int ret; | |
609 | struct ltt_kernel_stream *stream; | |
610 | ||
0525e9ae DG |
611 | assert(channel); |
612 | ||
f3ed775e DG |
613 | DBG("Flush buffer for channel %s", channel->channel->name); |
614 | ||
615 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
616 | DBG("Flushing channel stream %d", stream->fd); | |
617 | ret = kernctl_buffer_flush(stream->fd); | |
618 | if (ret < 0) { | |
df0f840b | 619 | PERROR("ioctl"); |
f3ed775e DG |
620 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
621 | stream->fd, ret); | |
622 | } | |
623 | } | |
624 | ||
625 | return 0; | |
626 | } | |
627 | ||
8c0faa1d | 628 | /* |
050349bb | 629 | * Stop tracing session. |
8c0faa1d DG |
630 | */ |
631 | int kernel_stop_session(struct ltt_kernel_session *session) | |
632 | { | |
633 | int ret; | |
634 | ||
0525e9ae DG |
635 | assert(session); |
636 | ||
8c0faa1d DG |
637 | ret = kernctl_stop_session(session->fd); |
638 | if (ret < 0) { | |
639 | goto error; | |
640 | } | |
641 | ||
642 | DBG("Kernel session stopped"); | |
643 | ||
644 | return 0; | |
645 | ||
646 | error: | |
647 | return ret; | |
648 | } | |
649 | ||
650 | /* | |
050349bb DG |
651 | * Open stream of channel, register it to the kernel tracer and add it |
652 | * to the stream list of the channel. | |
8c0faa1d | 653 | * |
1cfb4b98 MD |
654 | * Note: given that the streams may appear in random order wrt CPU |
655 | * number (e.g. cpu hotplug), the index value of the stream number in | |
656 | * the stream name is not necessarily linked to the CPU number. | |
657 | * | |
050349bb | 658 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 659 | */ |
f3ed775e | 660 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 661 | { |
1cfb4b98 | 662 | int ret; |
8c0faa1d DG |
663 | struct ltt_kernel_stream *lks; |
664 | ||
0525e9ae DG |
665 | assert(channel); |
666 | ||
5a47c6a2 | 667 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
668 | lks = trace_kernel_create_stream(channel->channel->name, |
669 | channel->stream_count); | |
8c0faa1d | 670 | if (lks == NULL) { |
799e2c4f MD |
671 | ret = close(ret); |
672 | if (ret) { | |
673 | PERROR("close"); | |
674 | } | |
8c0faa1d DG |
675 | goto error; |
676 | } | |
677 | ||
678 | lks->fd = ret; | |
7b395890 DG |
679 | /* Prevent fd duplication after execlp() */ |
680 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
681 | if (ret < 0) { | |
df0f840b | 682 | PERROR("fcntl session fd"); |
7b395890 DG |
683 | } |
684 | ||
1624d5b7 JD |
685 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
686 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
687 | ||
1cfb4b98 | 688 | /* Add stream to channel stream list */ |
8c0faa1d DG |
689 | cds_list_add(&lks->list, &channel->stream_list.head); |
690 | channel->stream_count++; | |
8c0faa1d | 691 | |
00e2e675 DG |
692 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
693 | lks->state); | |
54012638 | 694 | } |
8c0faa1d DG |
695 | |
696 | return channel->stream_count; | |
697 | ||
698 | error: | |
54012638 | 699 | return -1; |
8c0faa1d DG |
700 | } |
701 | ||
702 | /* | |
050349bb | 703 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 704 | */ |
f3ed775e | 705 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
706 | { |
707 | int ret; | |
708 | ||
0525e9ae DG |
709 | assert(session); |
710 | ||
8c0faa1d DG |
711 | ret = kernctl_create_stream(session->metadata->fd); |
712 | if (ret < 0) { | |
df0f840b | 713 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
714 | goto error; |
715 | } | |
716 | ||
717 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
718 | session->metadata_stream_fd = ret; | |
7b395890 DG |
719 | /* Prevent fd duplication after execlp() */ |
720 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
721 | if (ret < 0) { | |
df0f840b | 722 | PERROR("fcntl session fd"); |
7b395890 | 723 | } |
aaf26714 DG |
724 | |
725 | return 0; | |
726 | ||
727 | error: | |
54012638 | 728 | return -1; |
aaf26714 | 729 | } |
2ef84c95 DG |
730 | |
731 | /* | |
9f19cc17 | 732 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 733 | */ |
9f19cc17 | 734 | ssize_t kernel_list_events(int tracer_fd, struct lttng_event **events) |
2ef84c95 | 735 | { |
53efb85a | 736 | int fd, ret; |
9f19cc17 DG |
737 | char *event; |
738 | size_t nbmem, count = 0; | |
2ef84c95 | 739 | FILE *fp; |
9f19cc17 | 740 | struct lttng_event *elist; |
2ef84c95 | 741 | |
0525e9ae DG |
742 | assert(events); |
743 | ||
2ef84c95 DG |
744 | fd = kernctl_tracepoint_list(tracer_fd); |
745 | if (fd < 0) { | |
df0f840b | 746 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
747 | goto error; |
748 | } | |
749 | ||
750 | fp = fdopen(fd, "r"); | |
751 | if (fp == NULL) { | |
df0f840b | 752 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 753 | goto error_fp; |
2ef84c95 DG |
754 | } |
755 | ||
756 | /* | |
757 | * Init memory size counter | |
758 | * See kernel-ctl.h for explanation of this value | |
759 | */ | |
6725fe19 | 760 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
ba7f0ae5 | 761 | elist = zmalloc(sizeof(struct lttng_event) * nbmem); |
3b870559 MD |
762 | if (elist == NULL) { |
763 | PERROR("alloc list events"); | |
764 | count = -ENOMEM; | |
765 | goto end; | |
766 | } | |
2ef84c95 | 767 | |
53efb85a | 768 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 769 | if (count >= nbmem) { |
3b870559 | 770 | struct lttng_event *new_elist; |
53efb85a | 771 | size_t new_nbmem; |
3b870559 | 772 | |
53efb85a MD |
773 | new_nbmem = nbmem << 1; |
774 | DBG("Reallocating event list from %zu to %zu bytes", | |
775 | nbmem, new_nbmem); | |
776 | new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event)); | |
3b870559 | 777 | if (new_elist == NULL) { |
df0f840b | 778 | PERROR("realloc list events"); |
3b870559 MD |
779 | free(event); |
780 | free(elist); | |
61b73b12 MD |
781 | count = -ENOMEM; |
782 | goto end; | |
2ef84c95 | 783 | } |
53efb85a MD |
784 | /* Zero the new memory */ |
785 | memset(new_elist + nbmem, 0, | |
786 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
787 | nbmem = new_nbmem; | |
3b870559 | 788 | elist = new_elist; |
2ef84c95 | 789 | } |
99497cd0 MD |
790 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
791 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 792 | elist[count].enabled = -1; |
9f19cc17 | 793 | count++; |
3b870559 | 794 | free(event); |
2ef84c95 DG |
795 | } |
796 | ||
9f19cc17 | 797 | *events = elist; |
ced2f820 | 798 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 799 | end: |
799e2c4f MD |
800 | ret = fclose(fp); /* closes both fp and fd */ |
801 | if (ret) { | |
802 | PERROR("fclose"); | |
803 | } | |
9f19cc17 | 804 | return count; |
2ef84c95 | 805 | |
61b73b12 | 806 | error_fp: |
799e2c4f MD |
807 | ret = close(fd); |
808 | if (ret) { | |
809 | PERROR("close"); | |
810 | } | |
2ef84c95 DG |
811 | error: |
812 | return -1; | |
813 | } | |
096102bd DG |
814 | |
815 | /* | |
816 | * Get kernel version and validate it. | |
817 | */ | |
818 | int kernel_validate_version(int tracer_fd) | |
819 | { | |
820 | int ret; | |
821 | struct lttng_kernel_tracer_version version; | |
c052142c | 822 | struct lttng_kernel_tracer_abi_version abi_version; |
096102bd DG |
823 | |
824 | ret = kernctl_tracer_version(tracer_fd, &version); | |
825 | if (ret < 0) { | |
521dd134 | 826 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
827 | goto error; |
828 | } | |
829 | ||
830 | /* Validate version */ | |
c052142c MD |
831 | if (version.major != VERSION_MAJOR) { |
832 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", | |
833 | version.major, VERSION_MAJOR); | |
096102bd | 834 | goto error_version; |
096102bd | 835 | } |
c052142c MD |
836 | ret = kernctl_tracer_abi_version(tracer_fd, &abi_version); |
837 | if (ret < 0) { | |
521dd134 | 838 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
839 | goto error; |
840 | } | |
841 | if (abi_version.major != LTTNG_MODULES_ABI_MAJOR_VERSION) { | |
521dd134 | 842 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
c052142c MD |
843 | abi_version.major, abi_version.minor, |
844 | LTTNG_MODULES_ABI_MAJOR_VERSION); | |
845 | goto error; | |
846 | } | |
847 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
848 | version.major, version.minor, | |
849 | abi_version.major, abi_version.minor); | |
096102bd DG |
850 | return 0; |
851 | ||
852 | error_version: | |
096102bd DG |
853 | ret = -1; |
854 | ||
855 | error: | |
521dd134 | 856 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
857 | return ret; |
858 | } | |
335a95b7 MD |
859 | |
860 | /* | |
861 | * Kernel work-arounds called at the start of sessiond main(). | |
862 | */ | |
863 | int init_kernel_workarounds(void) | |
864 | { | |
8936c33a | 865 | int ret; |
335a95b7 MD |
866 | FILE *fp; |
867 | ||
868 | /* | |
869 | * boot_id needs to be read once before being used concurrently | |
870 | * to deal with a Linux kernel race. A fix is proposed for | |
871 | * upstream, but the work-around is needed for older kernels. | |
872 | */ | |
873 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
874 | if (!fp) { | |
875 | goto end_boot_id; | |
876 | } | |
877 | while (!feof(fp)) { | |
878 | char buf[37] = ""; | |
879 | ||
8936c33a DG |
880 | ret = fread(buf, 1, sizeof(buf), fp); |
881 | if (ret < 0) { | |
882 | /* Ignore error, we don't really care */ | |
883 | } | |
335a95b7 | 884 | } |
799e2c4f MD |
885 | ret = fclose(fp); |
886 | if (ret) { | |
887 | PERROR("fclose"); | |
888 | } | |
335a95b7 | 889 | end_boot_id: |
335a95b7 MD |
890 | return 0; |
891 | } | |
2f77fc4b DG |
892 | |
893 | /* | |
894 | * Complete teardown of a kernel session. | |
895 | */ | |
896 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
897 | { | |
898 | if (ksess == NULL) { | |
899 | DBG3("No kernel session when tearing down session"); | |
900 | return; | |
901 | } | |
902 | ||
903 | DBG("Tearing down kernel session"); | |
904 | ||
07b86b52 | 905 | /* |
15dc512a DG |
906 | * Destroy channels on the consumer if at least one FD has been sent and we |
907 | * are in no output mode because the streams are in *no* monitor mode so we | |
908 | * have to send a command to clean them up or else they leaked. | |
07b86b52 | 909 | */ |
15dc512a | 910 | if (!ksess->output_traces && ksess->consumer_fds_sent) { |
07b86b52 JD |
911 | int ret; |
912 | struct consumer_socket *socket; | |
913 | struct lttng_ht_iter iter; | |
914 | ||
915 | /* For each consumer socket. */ | |
d069d577 | 916 | rcu_read_lock(); |
07b86b52 JD |
917 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, |
918 | socket, node.node) { | |
919 | struct ltt_kernel_channel *chan; | |
920 | ||
921 | /* For each channel, ask the consumer to destroy it. */ | |
922 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
923 | ret = kernel_consumer_destroy_channel(socket, chan); | |
924 | if (ret < 0) { | |
925 | /* Consumer is probably dead. Use next socket. */ | |
926 | continue; | |
927 | } | |
928 | } | |
929 | } | |
d069d577 | 930 | rcu_read_unlock(); |
07b86b52 JD |
931 | } |
932 | ||
2f77fc4b DG |
933 | /* Close any relayd session */ |
934 | consumer_output_send_destroy_relayd(ksess->consumer); | |
935 | ||
936 | trace_kernel_destroy_session(ksess); | |
937 | } | |
fb5f35b6 DG |
938 | |
939 | /* | |
940 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
941 | */ | |
942 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
943 | { | |
944 | struct ltt_kernel_session *ksess = NULL; | |
945 | ||
946 | assert(kchan); | |
947 | assert(kchan->channel); | |
948 | ||
949 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
950 | ||
951 | /* Update channel count of associated session. */ | |
952 | if (kchan->session) { | |
953 | /* Keep pointer reference so we can update it after the destroy. */ | |
954 | ksess = kchan->session; | |
955 | } | |
956 | ||
957 | trace_kernel_destroy_channel(kchan); | |
958 | ||
959 | /* | |
960 | * At this point the kernel channel is not visible anymore. This is safe | |
961 | * since in order to work on a visible kernel session, the tracing session | |
962 | * lock (ltt_session.lock) MUST be acquired. | |
963 | */ | |
964 | if (ksess) { | |
965 | ksess->channel_count--; | |
966 | } | |
967 | } | |
6dc3064a DG |
968 | |
969 | /* | |
970 | * Take a snapshot for a given kernel session. | |
971 | * | |
2a06df8d | 972 | * Return 0 on success or else return a LTTNG_ERR code. |
6dc3064a DG |
973 | */ |
974 | int kernel_snapshot_record(struct ltt_kernel_session *ksess, | |
d07ceecd MD |
975 | struct snapshot_output *output, int wait, |
976 | uint64_t nb_packets_per_stream) | |
6dc3064a | 977 | { |
2a06df8d | 978 | int err, ret, saved_metadata_fd; |
6dc3064a DG |
979 | struct consumer_socket *socket; |
980 | struct lttng_ht_iter iter; | |
981 | struct ltt_kernel_metadata *saved_metadata; | |
982 | ||
983 | assert(ksess); | |
984 | assert(ksess->consumer); | |
985 | assert(output); | |
986 | ||
987 | DBG("Kernel snapshot record started"); | |
988 | ||
989 | /* Save current metadata since the following calls will change it. */ | |
990 | saved_metadata = ksess->metadata; | |
991 | saved_metadata_fd = ksess->metadata_stream_fd; | |
992 | ||
993 | rcu_read_lock(); | |
994 | ||
995 | ret = kernel_open_metadata(ksess); | |
996 | if (ret < 0) { | |
997 | ret = LTTNG_ERR_KERN_META_FAIL; | |
998 | goto error; | |
999 | } | |
1000 | ||
1001 | ret = kernel_open_metadata_stream(ksess); | |
1002 | if (ret < 0) { | |
1003 | ret = LTTNG_ERR_KERN_META_FAIL; | |
1004 | goto error_open_stream; | |
1005 | } | |
1006 | ||
1007 | /* Send metadata to consumer and snapshot everything. */ | |
1008 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1009 | socket, node.node) { | |
1010 | struct consumer_output *saved_output; | |
1011 | struct ltt_kernel_channel *chan; | |
6dc3064a DG |
1012 | |
1013 | /* | |
1014 | * Temporarly switch consumer output for our snapshot output. As long | |
1015 | * as the session lock is taken, this is safe. | |
1016 | */ | |
1017 | saved_output = ksess->consumer; | |
1018 | ksess->consumer = output->consumer; | |
1019 | ||
1020 | pthread_mutex_lock(socket->lock); | |
1021 | /* This stream must not be monitored by the consumer. */ | |
07b86b52 | 1022 | ret = kernel_consumer_add_metadata(socket, ksess, 0); |
6dc3064a | 1023 | pthread_mutex_unlock(socket->lock); |
07b86b52 | 1024 | /* Put back the saved consumer output into the session. */ |
6dc3064a DG |
1025 | ksess->consumer = saved_output; |
1026 | if (ret < 0) { | |
1027 | ret = LTTNG_ERR_KERN_CONSUMER_FAIL; | |
1028 | goto error_consumer; | |
1029 | } | |
1030 | ||
1031 | /* For each channel, ask the consumer to snapshot it. */ | |
1032 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
07b86b52 | 1033 | pthread_mutex_lock(socket->lock); |
6dc3064a | 1034 | ret = consumer_snapshot_channel(socket, chan->fd, output, 0, |
5c786ded JD |
1035 | ksess->uid, ksess->gid, |
1036 | DEFAULT_KERNEL_TRACE_DIR, wait, | |
d07ceecd | 1037 | nb_packets_per_stream); |
07b86b52 | 1038 | pthread_mutex_unlock(socket->lock); |
6dc3064a DG |
1039 | if (ret < 0) { |
1040 | ret = LTTNG_ERR_KERN_CONSUMER_FAIL; | |
2a06df8d DG |
1041 | (void) kernel_consumer_destroy_metadata(socket, |
1042 | ksess->metadata); | |
6dc3064a DG |
1043 | goto error_consumer; |
1044 | } | |
1045 | } | |
1046 | ||
1047 | /* Snapshot metadata, */ | |
07b86b52 | 1048 | pthread_mutex_lock(socket->lock); |
6dc3064a | 1049 | ret = consumer_snapshot_channel(socket, ksess->metadata->fd, output, |
5c786ded | 1050 | 1, ksess->uid, ksess->gid, |
d07ceecd | 1051 | DEFAULT_KERNEL_TRACE_DIR, wait, 0); |
07b86b52 | 1052 | pthread_mutex_unlock(socket->lock); |
6dc3064a DG |
1053 | if (ret < 0) { |
1054 | ret = LTTNG_ERR_KERN_CONSUMER_FAIL; | |
1055 | goto error_consumer; | |
1056 | } | |
07b86b52 JD |
1057 | |
1058 | /* | |
1059 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1060 | * it's not monitored on the consumer side. | |
1061 | */ | |
1062 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1063 | } |
1064 | ||
fac41e72 DG |
1065 | ret = LTTNG_OK; |
1066 | ||
6dc3064a DG |
1067 | error_consumer: |
1068 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1069 | err = close(ksess->metadata_stream_fd); |
1070 | if (err < 0) { | |
6dc3064a DG |
1071 | PERROR("close snapshot kernel"); |
1072 | } | |
1073 | ||
1074 | error_open_stream: | |
1075 | trace_kernel_destroy_metadata(ksess->metadata); | |
1076 | error: | |
1077 | /* Restore metadata state.*/ | |
1078 | ksess->metadata = saved_metadata; | |
1079 | ksess->metadata_stream_fd = saved_metadata_fd; | |
1080 | ||
1081 | rcu_read_unlock(); | |
1082 | return ret; | |
1083 | } | |
834978fd DG |
1084 | |
1085 | /* | |
1086 | * Get the syscall mask array from the kernel tracer. | |
1087 | * | |
1088 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1089 | * be freed. | |
1090 | */ | |
1091 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1092 | { | |
1093 | assert(syscall_mask); | |
1094 | assert(nr_bits); | |
1095 | ||
1096 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1097 | } | |
6e21424e JR |
1098 | |
1099 | /* | |
1100 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1101 | * version number. | |
1102 | * | |
1103 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1104 | * of errors. | |
1105 | */ | |
1106 | int kernel_supports_ring_buffer_snapshot_sample_positions(int tracer_fd) | |
1107 | { | |
1108 | int ret = 0; // Not supported by default | |
1109 | struct lttng_kernel_tracer_abi_version abi; | |
1110 | ||
1111 | ret = kernctl_tracer_abi_version(tracer_fd, &abi); | |
1112 | if (ret < 0) { | |
1113 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1114 | goto error; | |
1115 | } | |
1116 | ||
1117 | /* | |
1118 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1119 | */ | |
1120 | if (abi.major >= 2 && abi.minor >= 3) { | |
1121 | /* Supported */ | |
1122 | ret = 1; | |
1123 | } else { | |
1124 | /* Not supported */ | |
1125 | ret = 0; | |
1126 | } | |
1127 | error: | |
1128 | return ret; | |
1129 | } | |
6e0be6cc JD |
1130 | |
1131 | /* | |
1132 | * Rotate a kernel session. | |
1133 | * | |
1134 | * Return 0 on success or else return a LTTNG_ERR code. | |
1135 | */ | |
1136 | int kernel_rotate_session(struct ltt_session *session) | |
1137 | { | |
1138 | int ret; | |
1139 | struct consumer_socket *socket; | |
1140 | struct lttng_ht_iter iter; | |
1141 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1142 | ||
1143 | assert(ksess); | |
1144 | assert(ksess->consumer); | |
1145 | ||
1146 | DBG("Rotate kernel session started"); | |
1147 | ||
1148 | rcu_read_lock(); | |
1149 | ||
1150 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1151 | socket, node.node) { | |
1152 | struct ltt_kernel_channel *chan; | |
1153 | ||
1154 | /* | |
1155 | * Account the metadata channel first to make sure the | |
1156 | * number of channels waiting for a rotation cannot | |
1157 | * reach 0 before we complete the iteration over all | |
1158 | * the channels. | |
1159 | */ | |
1160 | ret = rotate_add_channel_pending(ksess->metadata->fd, | |
1161 | LTTNG_DOMAIN_KERNEL, session); | |
1162 | if (ret < 0) { | |
1163 | ret = LTTNG_ERR_KERN_CONSUMER_FAIL; | |
1164 | pthread_mutex_unlock(socket->lock); | |
1165 | goto error; | |
1166 | } | |
1167 | ||
1168 | /* For each channel, ask the consumer to rotate it. */ | |
1169 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1170 | /* FIXME: is that lock necessary, we don't do it in UST ? */ | |
1171 | pthread_mutex_lock(socket->lock); | |
1172 | ret = rotate_add_channel_pending(chan->fd, | |
1173 | LTTNG_DOMAIN_KERNEL, session); | |
1174 | if (ret < 0) { | |
1175 | ret = LTTNG_ERR_KERN_CONSUMER_FAIL; | |
1176 | pthread_mutex_unlock(socket->lock); | |
1177 | goto error; | |
1178 | } | |
1179 | ||
1180 | ret = consumer_rotate_channel(socket, chan->fd, | |
1181 | ksess->uid, ksess->gid, ksess->consumer, | |
d3dedf27 JD |
1182 | "", 0, session->rotate_count, |
1183 | &session->rotate_pending_relay); | |
6e0be6cc JD |
1184 | if (ret < 0) { |
1185 | ret = LTTNG_ERR_KERN_CONSUMER_FAIL; | |
1186 | pthread_mutex_unlock(socket->lock); | |
1187 | goto error; | |
1188 | } | |
1189 | ||
1190 | pthread_mutex_unlock(socket->lock); | |
1191 | } | |
1192 | ||
1193 | /* | |
1194 | * Rotate the metadata channel. | |
1195 | */ | |
1196 | pthread_mutex_lock(socket->lock); | |
1197 | ret = consumer_rotate_channel(socket, ksess->metadata->fd, | |
2d7d73bc | 1198 | ksess->uid, ksess->gid, ksess->consumer, "", 1, |
d3dedf27 JD |
1199 | session->rotate_count, |
1200 | &session->rotate_pending_relay); | |
6e0be6cc JD |
1201 | if (ret < 0) { |
1202 | ret = LTTNG_ERR_KERN_CONSUMER_FAIL; | |
1203 | pthread_mutex_unlock(socket->lock); | |
1204 | goto error; | |
1205 | } | |
1206 | pthread_mutex_unlock(socket->lock); | |
1207 | } | |
6e0be6cc JD |
1208 | |
1209 | ret = LTTNG_OK; | |
1210 | ||
1211 | error: | |
1212 | rcu_read_unlock(); | |
1213 | return ret; | |
1214 | } |