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" |
5c408ad8 | 36 | #include "rotate.h" |
20fe2104 | 37 | |
e1f3997a JD |
38 | /* |
39 | * Key used to reference a channel between the sessiond and the consumer. This | |
40 | * is only read and updated with the session_list lock held. | |
41 | */ | |
42 | static uint64_t next_kernel_channel_key; | |
43 | ||
410b78a0 FD |
44 | #include <lttng/userspace-probe.h> |
45 | #include <lttng/userspace-probe-internal.h> | |
d65106b1 | 46 | /* |
050349bb | 47 | * Add context on a kernel channel. |
df3c77c8 JG |
48 | * |
49 | * Assumes the ownership of ctx. | |
d65106b1 DG |
50 | */ |
51 | int kernel_add_channel_context(struct ltt_kernel_channel *chan, | |
645328ae | 52 | struct ltt_kernel_context *ctx) |
d65106b1 DG |
53 | { |
54 | int ret; | |
55 | ||
0525e9ae DG |
56 | assert(chan); |
57 | assert(ctx); | |
58 | ||
d65106b1 | 59 | DBG("Adding context to channel %s", chan->channel->name); |
645328ae | 60 | ret = kernctl_add_context(chan->fd, &ctx->ctx); |
d65106b1 | 61 | if (ret < 0) { |
32af2c95 | 62 | switch (-ret) { |
1ae5e83e JD |
63 | case ENOSYS: |
64 | /* Exists but not available for this kernel */ | |
65 | ret = LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE; | |
66 | goto error; | |
67 | case EEXIST: | |
b579acd9 DG |
68 | /* If EEXIST, we just ignore the error */ |
69 | ret = 0; | |
1ae5e83e JD |
70 | goto end; |
71 | default: | |
72 | PERROR("add context ioctl"); | |
73 | ret = LTTNG_ERR_KERN_CONTEXT_FAIL; | |
74 | goto error; | |
b579acd9 | 75 | } |
d65106b1 | 76 | } |
21ed98c1 | 77 | ret = 0; |
d65106b1 | 78 | |
1ae5e83e | 79 | end: |
645328ae | 80 | cds_list_add_tail(&ctx->list, &chan->ctx_list); |
ba985c3a | 81 | ctx->in_list = true; |
df3c77c8 | 82 | ctx = NULL; |
d65106b1 | 83 | error: |
df3c77c8 JG |
84 | if (ctx) { |
85 | trace_kernel_destroy_context(ctx); | |
86 | } | |
d65106b1 DG |
87 | return ret; |
88 | } | |
89 | ||
20fe2104 | 90 | /* |
050349bb DG |
91 | * Create a new kernel session, register it to the kernel tracer and add it to |
92 | * the session daemon session. | |
20fe2104 | 93 | */ |
8c0faa1d | 94 | int kernel_create_session(struct ltt_session *session, int tracer_fd) |
20fe2104 DG |
95 | { |
96 | int ret; | |
97 | struct ltt_kernel_session *lks; | |
98 | ||
0525e9ae DG |
99 | assert(session); |
100 | ||
54012638 | 101 | /* Allocate data structure */ |
dec56f6c | 102 | lks = trace_kernel_create_session(); |
20fe2104 | 103 | if (lks == NULL) { |
54012638 | 104 | ret = -1; |
20fe2104 DG |
105 | goto error; |
106 | } | |
107 | ||
54012638 | 108 | /* Kernel tracer session creation */ |
20fe2104 DG |
109 | ret = kernctl_create_session(tracer_fd); |
110 | if (ret < 0) { | |
df0f840b | 111 | PERROR("ioctl kernel create session"); |
20fe2104 DG |
112 | goto error; |
113 | } | |
114 | ||
20fe2104 | 115 | lks->fd = ret; |
7b395890 DG |
116 | /* Prevent fd duplication after execlp() */ |
117 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
118 | if (ret < 0) { | |
df0f840b | 119 | PERROR("fcntl session fd"); |
7b395890 DG |
120 | } |
121 | ||
53632229 | 122 | lks->id = session->id; |
3bd1e081 | 123 | lks->consumer_fds_sent = 0; |
8c0faa1d | 124 | session->kernel_session = lks; |
8c0faa1d DG |
125 | |
126 | DBG("Kernel session created (fd: %d)", lks->fd); | |
20fe2104 | 127 | |
49938fb6 JR |
128 | ret = kernctl_session_set_name(lks->fd, session->name); |
129 | if (ret) { | |
130 | WARN("Could not set kernel session name"); | |
131 | } | |
132 | ||
20fe2104 DG |
133 | return 0; |
134 | ||
135 | error: | |
5f62c685 DG |
136 | if (lks) { |
137 | trace_kernel_destroy_session(lks); | |
138 | } | |
20fe2104 DG |
139 | return ret; |
140 | } | |
141 | ||
142 | /* | |
050349bb DG |
143 | * Create a kernel channel, register it to the kernel tracer and add it to the |
144 | * kernel session. | |
20fe2104 | 145 | */ |
050349bb | 146 | int kernel_create_channel(struct ltt_kernel_session *session, |
fdd9eb17 | 147 | struct lttng_channel *chan) |
20fe2104 DG |
148 | { |
149 | int ret; | |
150 | struct ltt_kernel_channel *lkc; | |
20fe2104 | 151 | |
0525e9ae DG |
152 | assert(session); |
153 | assert(chan); | |
0525e9ae | 154 | |
54012638 | 155 | /* Allocate kernel channel */ |
fdd9eb17 | 156 | lkc = trace_kernel_create_channel(chan); |
54012638 | 157 | if (lkc == NULL) { |
20fe2104 DG |
158 | goto error; |
159 | } | |
160 | ||
ecc48a90 | 161 | DBG3("Kernel create channel %s with attr: %d, %" PRIu64 ", %" PRIu64 ", %u, %u, %d, %d", |
fdd9eb17 | 162 | chan->name, lkc->channel->attr.overwrite, |
173af62f DG |
163 | lkc->channel->attr.subbuf_size, lkc->channel->attr.num_subbuf, |
164 | lkc->channel->attr.switch_timer_interval, lkc->channel->attr.read_timer_interval, | |
ecc48a90 | 165 | lkc->channel->attr.live_timer_interval, lkc->channel->attr.output); |
173af62f | 166 | |
54012638 | 167 | /* Kernel tracer channel creation */ |
f3ed775e | 168 | ret = kernctl_create_channel(session->fd, &lkc->channel->attr); |
20fe2104 | 169 | if (ret < 0) { |
df0f840b | 170 | PERROR("ioctl kernel create channel"); |
20fe2104 DG |
171 | goto error; |
172 | } | |
173 | ||
54012638 | 174 | /* Setup the channel fd */ |
20fe2104 | 175 | lkc->fd = ret; |
7b395890 DG |
176 | /* Prevent fd duplication after execlp() */ |
177 | ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC); | |
178 | if (ret < 0) { | |
df0f840b | 179 | PERROR("fcntl session fd"); |
7b395890 DG |
180 | } |
181 | ||
54012638 | 182 | /* Add channel to session */ |
8c0faa1d DG |
183 | cds_list_add(&lkc->list, &session->channel_list.head); |
184 | session->channel_count++; | |
fb5f35b6 | 185 | lkc->session = session; |
e1f3997a | 186 | lkc->key = ++next_kernel_channel_key; |
20fe2104 | 187 | |
e1f3997a JD |
188 | DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")", |
189 | lkc->channel->name, lkc->fd, lkc->key); | |
20fe2104 DG |
190 | |
191 | return 0; | |
192 | ||
193 | error: | |
5f62c685 DG |
194 | if (lkc) { |
195 | free(lkc->channel); | |
196 | free(lkc); | |
197 | } | |
54012638 | 198 | return -1; |
20fe2104 | 199 | } |
f34daff7 | 200 | |
410b78a0 FD |
201 | /* |
202 | * Compute the offset of the instrumentation byte in the binary based on the | |
203 | * function probe location using the ELF lookup method. | |
204 | * | |
205 | * Returns 0 on success and set the offset out parameter to the offset of the | |
206 | * elf symbol | |
207 | * Returns -1 on error | |
208 | */ | |
209 | static | |
210 | int extract_userspace_probe_offset_function_elf( | |
87597c2c | 211 | const struct lttng_userspace_probe_location *probe_location, |
410b78a0 FD |
212 | struct ltt_kernel_session *session, uint64_t *offset) |
213 | { | |
214 | int fd; | |
215 | int ret = 0; | |
216 | const char *symbol = NULL; | |
87597c2c | 217 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
218 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; |
219 | ||
410b78a0 FD |
220 | assert(lttng_userspace_probe_location_get_type(probe_location) == |
221 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_FUNCTION); | |
222 | ||
223 | lookup = lttng_userspace_probe_location_get_lookup_method( | |
224 | probe_location); | |
225 | if (!lookup) { | |
226 | ret = -1; | |
227 | goto end; | |
228 | } | |
229 | ||
230 | lookup_method_type = | |
231 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
232 | ||
233 | assert(lookup_method_type == | |
234 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF); | |
235 | ||
236 | symbol = lttng_userspace_probe_location_function_get_function_name( | |
237 | probe_location); | |
238 | if (!symbol) { | |
239 | ret = -1; | |
240 | goto end; | |
241 | } | |
242 | ||
243 | fd = lttng_userspace_probe_location_function_get_binary_fd(probe_location); | |
244 | if (fd < 0) { | |
245 | ret = -1; | |
246 | goto end; | |
247 | } | |
248 | ||
249 | ret = run_as_extract_elf_symbol_offset(fd, symbol, session->uid, | |
250 | session->gid, offset); | |
251 | if (ret < 0) { | |
252 | DBG("userspace probe offset calculation failed for " | |
253 | "function %s", symbol); | |
254 | goto end; | |
255 | } | |
256 | ||
257 | DBG("userspace probe elf offset for %s is 0x%jd", symbol, (intmax_t)(*offset)); | |
258 | end: | |
259 | return ret; | |
260 | } | |
261 | ||
262 | /* | |
263 | * Compute the offsets of the instrumentation bytes in the binary based on the | |
264 | * tracepoint probe location using the SDT lookup method. This function | |
265 | * allocates the offsets buffer, the caller must free it. | |
266 | * | |
267 | * Returns 0 on success and set the offset out parameter to the offsets of the | |
268 | * SDT tracepoint. | |
269 | * Returns -1 on error. | |
270 | */ | |
271 | static | |
272 | int extract_userspace_probe_offset_tracepoint_sdt( | |
87597c2c | 273 | const struct lttng_userspace_probe_location *probe_location, |
410b78a0 FD |
274 | struct ltt_kernel_session *session, uint64_t **offsets, |
275 | uint32_t *offsets_count) | |
276 | { | |
277 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; | |
87597c2c | 278 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
279 | const char *probe_name = NULL, *provider_name = NULL; |
280 | int ret = 0; | |
281 | int fd, i; | |
282 | ||
283 | assert(lttng_userspace_probe_location_get_type(probe_location) == | |
284 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_TRACEPOINT); | |
285 | ||
286 | lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); | |
287 | if (!lookup) { | |
288 | ret = -1; | |
289 | goto end; | |
290 | } | |
291 | ||
292 | lookup_method_type = | |
293 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
294 | ||
295 | assert(lookup_method_type == | |
296 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT); | |
297 | ||
298 | ||
299 | probe_name = lttng_userspace_probe_location_tracepoint_get_probe_name( | |
300 | probe_location); | |
301 | if (!probe_name) { | |
302 | ret = -1; | |
303 | goto end; | |
304 | } | |
305 | ||
306 | provider_name = lttng_userspace_probe_location_tracepoint_get_provider_name( | |
307 | probe_location); | |
308 | if (!provider_name) { | |
309 | ret = -1; | |
310 | goto end; | |
311 | } | |
312 | ||
313 | fd = lttng_userspace_probe_location_tracepoint_get_binary_fd(probe_location); | |
314 | if (fd < 0) { | |
315 | ret = -1; | |
316 | goto end; | |
317 | } | |
318 | ||
319 | ret = run_as_extract_sdt_probe_offsets(fd, provider_name, probe_name, | |
320 | session->uid, session->gid, offsets, offsets_count); | |
321 | if (ret < 0) { | |
322 | DBG("userspace probe offset calculation failed for sdt " | |
323 | "probe %s:%s", provider_name, probe_name); | |
324 | goto end; | |
325 | } | |
326 | ||
327 | if (*offsets_count == 0) { | |
328 | DBG("no userspace probe offset found"); | |
329 | goto end; | |
330 | } | |
331 | ||
332 | DBG("%u userspace probe SDT offsets found for %s:%s at:", | |
333 | *offsets_count, provider_name, probe_name); | |
334 | for (i = 0; i < *offsets_count; i++) { | |
335 | DBG("\t0x%jd", (intmax_t)((*offsets)[i])); | |
336 | } | |
337 | end: | |
338 | return ret; | |
339 | } | |
340 | ||
341 | /* | |
342 | * Extract the offsets of the instrumentation point for the different lookup | |
343 | * methods. | |
344 | */ | |
345 | static | |
346 | int userspace_probe_add_callsites(struct lttng_event *ev, | |
347 | struct ltt_kernel_session *session, int fd) | |
348 | { | |
87597c2c | 349 | const struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL; |
410b78a0 | 350 | enum lttng_userspace_probe_location_lookup_method_type type; |
87597c2c | 351 | const struct lttng_userspace_probe_location *location = NULL; |
410b78a0 FD |
352 | int ret; |
353 | ||
354 | assert(ev); | |
355 | assert(ev->type == LTTNG_EVENT_USERSPACE_PROBE); | |
356 | ||
357 | location = lttng_event_get_userspace_probe_location(ev); | |
358 | if (!location) { | |
359 | ret = -1; | |
360 | goto end; | |
361 | } | |
362 | lookup_method = | |
363 | lttng_userspace_probe_location_get_lookup_method(location); | |
364 | if (!lookup_method) { | |
365 | ret = -1; | |
366 | goto end; | |
367 | } | |
368 | ||
369 | type = lttng_userspace_probe_location_lookup_method_get_type(lookup_method); | |
370 | switch (type) { | |
371 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: | |
372 | { | |
373 | struct lttng_kernel_event_callsite callsite; | |
374 | uint64_t offset; | |
375 | ||
376 | ret = extract_userspace_probe_offset_function_elf(location, session, &offset); | |
377 | if (ret) { | |
378 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
379 | goto end; | |
380 | } | |
381 | ||
382 | callsite.u.uprobe.offset = offset; | |
383 | ret = kernctl_add_callsite(fd, &callsite); | |
384 | if (ret) { | |
385 | WARN("Adding callsite to userspace probe " | |
386 | "event %s failed.", ev->name); | |
387 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
388 | goto end; | |
389 | } | |
390 | break; | |
391 | } | |
392 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: | |
393 | { | |
394 | int i; | |
395 | uint64_t *offsets = NULL; | |
396 | uint32_t offsets_count; | |
397 | struct lttng_kernel_event_callsite callsite; | |
398 | ||
399 | /* | |
400 | * This call allocates the offsets buffer. This buffer must be freed | |
401 | * by the caller | |
402 | */ | |
403 | ret = extract_userspace_probe_offset_tracepoint_sdt(location, session, | |
404 | &offsets, &offsets_count); | |
405 | if (ret) { | |
406 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
407 | goto end; | |
408 | } | |
409 | for (i = 0; i < offsets_count; i++) { | |
410 | callsite.u.uprobe.offset = offsets[i]; | |
411 | ret = kernctl_add_callsite(fd, &callsite); | |
412 | if (ret) { | |
413 | WARN("Adding callsite to userspace probe " | |
414 | "event %s failed.", ev->name); | |
415 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
416 | free(offsets); | |
417 | goto end; | |
418 | } | |
419 | } | |
420 | free(offsets); | |
421 | break; | |
422 | } | |
423 | default: | |
424 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
425 | goto end; | |
426 | } | |
427 | end: | |
428 | return ret; | |
429 | } | |
430 | ||
f34daff7 | 431 | /* |
050349bb DG |
432 | * Create a kernel event, enable it to the kernel tracer and add it to the |
433 | * channel event list of the kernel session. | |
49d21f93 | 434 | * We own filter_expression and filter. |
f34daff7 | 435 | */ |
050349bb | 436 | int kernel_create_event(struct lttng_event *ev, |
00a62084 MD |
437 | struct ltt_kernel_channel *channel, |
438 | char *filter_expression, | |
439 | struct lttng_filter_bytecode *filter) | |
f34daff7 | 440 | { |
71a3bb01 FD |
441 | int err, fd; |
442 | enum lttng_error_code ret; | |
f34daff7 | 443 | struct ltt_kernel_event *event; |
f34daff7 | 444 | |
0525e9ae DG |
445 | assert(ev); |
446 | assert(channel); | |
447 | ||
a969e101 | 448 | /* We pass ownership of filter_expression and filter */ |
71a3bb01 FD |
449 | ret = trace_kernel_create_event(ev, filter_expression, |
450 | filter, &event); | |
451 | if (ret != LTTNG_OK) { | |
f34daff7 DG |
452 | goto error; |
453 | } | |
454 | ||
71a3bb01 FD |
455 | fd = kernctl_create_event(channel->fd, event->event); |
456 | if (fd < 0) { | |
457 | switch (-fd) { | |
bd29c13d | 458 | case EEXIST: |
71a3bb01 | 459 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
bd29c13d DG |
460 | break; |
461 | case ENOSYS: | |
462 | WARN("Event type not implemented"); | |
71a3bb01 | 463 | ret = LTTNG_ERR_KERN_EVENT_ENOSYS; |
bd29c13d | 464 | break; |
8197a339 DG |
465 | case ENOENT: |
466 | WARN("Event %s not found!", ev->name); | |
71a3bb01 | 467 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
8197a339 | 468 | break; |
bd29c13d | 469 | default: |
71a3bb01 | 470 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
d87bfb32 DG |
471 | PERROR("create event ioctl"); |
472 | } | |
e953ef25 | 473 | goto free_event; |
8c0faa1d | 474 | } |
f34daff7 | 475 | |
d0ae4ea8 | 476 | event->type = ev->type; |
71a3bb01 | 477 | event->fd = fd; |
7b395890 | 478 | /* Prevent fd duplication after execlp() */ |
71a3bb01 FD |
479 | err = fcntl(event->fd, F_SETFD, FD_CLOEXEC); |
480 | if (err < 0) { | |
df0f840b | 481 | PERROR("fcntl session fd"); |
7b395890 DG |
482 | } |
483 | ||
00a62084 | 484 | if (filter) { |
71a3bb01 FD |
485 | err = kernctl_filter(event->fd, filter); |
486 | if (err < 0) { | |
487 | switch (-err) { | |
488 | case ENOMEM: | |
489 | ret = LTTNG_ERR_FILTER_NOMEM; | |
490 | break; | |
491 | default: | |
492 | ret = LTTNG_ERR_FILTER_INVAL; | |
493 | break; | |
494 | } | |
00a62084 MD |
495 | goto filter_error; |
496 | } | |
497 | } | |
498 | ||
dcabc190 FD |
499 | if (ev->type == LTTNG_EVENT_USERSPACE_PROBE) { |
500 | ret = userspace_probe_add_callsites(ev, channel->session, event->fd); | |
501 | if (ret) { | |
502 | goto add_callsite_error; | |
503 | } | |
504 | } | |
505 | ||
71a3bb01 FD |
506 | err = kernctl_enable(event->fd); |
507 | if (err < 0) { | |
508 | switch (-err) { | |
00a62084 MD |
509 | case EEXIST: |
510 | ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
511 | break; | |
512 | default: | |
513 | PERROR("enable kernel event"); | |
71a3bb01 | 514 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
00a62084 MD |
515 | break; |
516 | } | |
517 | goto enable_error; | |
518 | } | |
519 | ||
f3ed775e DG |
520 | /* Add event to event list */ |
521 | cds_list_add(&event->list, &channel->events_list.head); | |
cbbbb275 DG |
522 | channel->event_count++; |
523 | ||
e953ef25 DG |
524 | DBG("Event %s created (fd: %d)", ev->name, event->fd); |
525 | ||
526 | return 0; | |
527 | ||
dcabc190 | 528 | add_callsite_error: |
00a62084 MD |
529 | enable_error: |
530 | filter_error: | |
531 | { | |
532 | int closeret; | |
533 | ||
534 | closeret = close(event->fd); | |
535 | if (closeret) { | |
536 | PERROR("close event fd"); | |
537 | } | |
538 | } | |
e953ef25 DG |
539 | free_event: |
540 | free(event); | |
541 | error: | |
d87bfb32 | 542 | return ret; |
e953ef25 DG |
543 | } |
544 | ||
26cc6b4e | 545 | /* |
050349bb | 546 | * Disable a kernel channel. |
26cc6b4e DG |
547 | */ |
548 | int kernel_disable_channel(struct ltt_kernel_channel *chan) | |
549 | { | |
550 | int ret; | |
551 | ||
0525e9ae DG |
552 | assert(chan); |
553 | ||
26cc6b4e DG |
554 | ret = kernctl_disable(chan->fd); |
555 | if (ret < 0) { | |
df0f840b | 556 | PERROR("disable chan ioctl"); |
26cc6b4e DG |
557 | goto error; |
558 | } | |
559 | ||
560 | chan->enabled = 0; | |
e1f3997a JD |
561 | DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")", |
562 | chan->channel->name, chan->fd, chan->key); | |
26cc6b4e DG |
563 | |
564 | return 0; | |
565 | ||
566 | error: | |
567 | return ret; | |
568 | } | |
569 | ||
d36b8583 | 570 | /* |
050349bb | 571 | * Enable a kernel channel. |
d36b8583 DG |
572 | */ |
573 | int kernel_enable_channel(struct ltt_kernel_channel *chan) | |
574 | { | |
575 | int ret; | |
576 | ||
0525e9ae DG |
577 | assert(chan); |
578 | ||
d36b8583 | 579 | ret = kernctl_enable(chan->fd); |
32af2c95 | 580 | if (ret < 0 && ret != -EEXIST) { |
df0f840b | 581 | PERROR("Enable kernel chan"); |
d36b8583 DG |
582 | goto error; |
583 | } | |
584 | ||
585 | chan->enabled = 1; | |
e1f3997a JD |
586 | DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")", |
587 | chan->channel->name, chan->fd, chan->key); | |
d36b8583 DG |
588 | |
589 | return 0; | |
590 | ||
591 | error: | |
592 | return ret; | |
593 | } | |
594 | ||
19e70852 | 595 | /* |
050349bb | 596 | * Enable a kernel event. |
19e70852 DG |
597 | */ |
598 | int kernel_enable_event(struct ltt_kernel_event *event) | |
599 | { | |
600 | int ret; | |
601 | ||
0525e9ae DG |
602 | assert(event); |
603 | ||
19e70852 | 604 | ret = kernctl_enable(event->fd); |
42224349 | 605 | if (ret < 0) { |
32af2c95 | 606 | switch (-ret) { |
42224349 | 607 | case EEXIST: |
f73fabfd | 608 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
609 | break; |
610 | default: | |
611 | PERROR("enable kernel event"); | |
612 | break; | |
613 | } | |
19e70852 DG |
614 | goto error; |
615 | } | |
616 | ||
617 | event->enabled = 1; | |
618 | DBG("Kernel event %s enabled (fd: %d)", event->event->name, event->fd); | |
619 | ||
620 | return 0; | |
621 | ||
622 | error: | |
d36b8583 | 623 | return ret; |
19e70852 DG |
624 | } |
625 | ||
e953ef25 | 626 | /* |
050349bb | 627 | * Disable a kernel event. |
e953ef25 | 628 | */ |
19e70852 | 629 | int kernel_disable_event(struct ltt_kernel_event *event) |
e953ef25 DG |
630 | { |
631 | int ret; | |
19e70852 | 632 | |
0525e9ae DG |
633 | assert(event); |
634 | ||
19e70852 | 635 | ret = kernctl_disable(event->fd); |
42224349 | 636 | if (ret < 0) { |
32af2c95 | 637 | switch (-ret) { |
42224349 | 638 | case EEXIST: |
f73fabfd | 639 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
640 | break; |
641 | default: | |
642 | PERROR("disable kernel event"); | |
643 | break; | |
644 | } | |
19e70852 | 645 | goto error; |
e953ef25 | 646 | } |
f3ed775e | 647 | |
19e70852 DG |
648 | event->enabled = 0; |
649 | DBG("Kernel event %s disabled (fd: %d)", event->event->name, event->fd); | |
650 | ||
f34daff7 DG |
651 | return 0; |
652 | ||
653 | error: | |
d36b8583 | 654 | return ret; |
f34daff7 | 655 | } |
aaf26714 | 656 | |
6e911cad | 657 | |
ccf10263 MD |
658 | int kernel_track_pid(struct ltt_kernel_session *session, int pid) |
659 | { | |
7c493d31 MD |
660 | int ret; |
661 | ||
ccf10263 MD |
662 | DBG("Kernel track PID %d for session id %" PRIu64 ".", |
663 | pid, session->id); | |
7c493d31 MD |
664 | ret = kernctl_track_pid(session->fd, pid); |
665 | if (!ret) { | |
666 | return LTTNG_OK; | |
667 | } | |
32af2c95 | 668 | switch (-ret) { |
7c493d31 MD |
669 | case EINVAL: |
670 | return LTTNG_ERR_INVALID; | |
671 | case ENOMEM: | |
672 | return LTTNG_ERR_NOMEM; | |
673 | case EEXIST: | |
674 | return LTTNG_ERR_PID_TRACKED; | |
675 | default: | |
676 | return LTTNG_ERR_UNK; | |
677 | } | |
ccf10263 MD |
678 | } |
679 | ||
680 | int kernel_untrack_pid(struct ltt_kernel_session *session, int pid) | |
681 | { | |
7c493d31 MD |
682 | int ret; |
683 | ||
ccf10263 MD |
684 | DBG("Kernel untrack PID %d for session id %" PRIu64 ".", |
685 | pid, session->id); | |
7c493d31 MD |
686 | ret = kernctl_untrack_pid(session->fd, pid); |
687 | if (!ret) { | |
688 | return LTTNG_OK; | |
689 | } | |
32af2c95 | 690 | switch (-ret) { |
7c493d31 MD |
691 | case EINVAL: |
692 | return LTTNG_ERR_INVALID; | |
693 | case ENOMEM: | |
694 | return LTTNG_ERR_NOMEM; | |
695 | case ENOENT: | |
696 | return LTTNG_ERR_PID_NOT_TRACKED; | |
697 | default: | |
698 | return LTTNG_ERR_UNK; | |
699 | } | |
ccf10263 MD |
700 | } |
701 | ||
a5dfbb9d MD |
702 | ssize_t kernel_list_tracker_pids(struct ltt_kernel_session *session, |
703 | int **_pids) | |
704 | { | |
705 | int fd, ret; | |
706 | int pid; | |
707 | ssize_t nbmem, count = 0; | |
708 | FILE *fp; | |
709 | int *pids; | |
710 | ||
711 | fd = kernctl_list_tracker_pids(session->fd); | |
712 | if (fd < 0) { | |
713 | PERROR("kernel tracker pids list"); | |
714 | goto error; | |
715 | } | |
716 | ||
717 | fp = fdopen(fd, "r"); | |
718 | if (fp == NULL) { | |
719 | PERROR("kernel tracker pids list fdopen"); | |
720 | goto error_fp; | |
721 | } | |
722 | ||
723 | nbmem = KERNEL_TRACKER_PIDS_INIT_LIST_SIZE; | |
724 | pids = zmalloc(sizeof(*pids) * nbmem); | |
725 | if (pids == NULL) { | |
726 | PERROR("alloc list pids"); | |
727 | count = -ENOMEM; | |
728 | goto end; | |
729 | } | |
730 | ||
731 | while (fscanf(fp, "process { pid = %u; };\n", &pid) == 1) { | |
732 | if (count >= nbmem) { | |
733 | int *new_pids; | |
734 | size_t new_nbmem; | |
735 | ||
736 | new_nbmem = nbmem << 1; | |
737 | DBG("Reallocating pids list from %zu to %zu entries", | |
738 | nbmem, new_nbmem); | |
739 | new_pids = realloc(pids, new_nbmem * sizeof(*new_pids)); | |
740 | if (new_pids == NULL) { | |
741 | PERROR("realloc list events"); | |
742 | free(pids); | |
743 | count = -ENOMEM; | |
744 | goto end; | |
745 | } | |
746 | /* Zero the new memory */ | |
747 | memset(new_pids + nbmem, 0, | |
748 | (new_nbmem - nbmem) * sizeof(*new_pids)); | |
749 | nbmem = new_nbmem; | |
750 | pids = new_pids; | |
751 | } | |
752 | pids[count++] = pid; | |
753 | } | |
754 | ||
755 | *_pids = pids; | |
756 | DBG("Kernel list tracker pids done (%zd pids)", count); | |
757 | end: | |
758 | ret = fclose(fp); /* closes both fp and fd */ | |
759 | if (ret) { | |
760 | PERROR("fclose"); | |
761 | } | |
762 | return count; | |
763 | ||
764 | error_fp: | |
765 | ret = close(fd); | |
766 | if (ret) { | |
767 | PERROR("close"); | |
768 | } | |
769 | error: | |
770 | return -1; | |
771 | } | |
772 | ||
aaf26714 | 773 | /* |
050349bb DG |
774 | * Create kernel metadata, open from the kernel tracer and add it to the |
775 | * kernel session. | |
aaf26714 | 776 | */ |
a4b92340 | 777 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
778 | { |
779 | int ret; | |
74024a21 | 780 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 781 | |
0525e9ae DG |
782 | assert(session); |
783 | ||
54012638 | 784 | /* Allocate kernel metadata */ |
a4b92340 | 785 | lkm = trace_kernel_create_metadata(); |
54012638 | 786 | if (lkm == NULL) { |
aaf26714 DG |
787 | goto error; |
788 | } | |
789 | ||
54012638 | 790 | /* Kernel tracer metadata creation */ |
f3ed775e | 791 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 792 | if (ret < 0) { |
74024a21 | 793 | goto error_open; |
aaf26714 DG |
794 | } |
795 | ||
8c0faa1d | 796 | lkm->fd = ret; |
d40f0359 | 797 | lkm->key = ++next_kernel_channel_key; |
7b395890 DG |
798 | /* Prevent fd duplication after execlp() */ |
799 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
800 | if (ret < 0) { | |
df0f840b | 801 | PERROR("fcntl session fd"); |
7b395890 DG |
802 | } |
803 | ||
aaf26714 | 804 | session->metadata = lkm; |
8c0faa1d | 805 | |
00e2e675 | 806 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
807 | |
808 | return 0; | |
809 | ||
74024a21 DG |
810 | error_open: |
811 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 812 | error: |
54012638 | 813 | return -1; |
8c0faa1d DG |
814 | } |
815 | ||
816 | /* | |
050349bb | 817 | * Start tracing session. |
8c0faa1d DG |
818 | */ |
819 | int kernel_start_session(struct ltt_kernel_session *session) | |
820 | { | |
821 | int ret; | |
822 | ||
0525e9ae DG |
823 | assert(session); |
824 | ||
8c0faa1d DG |
825 | ret = kernctl_start_session(session->fd); |
826 | if (ret < 0) { | |
df0f840b | 827 | PERROR("ioctl start session"); |
8c0faa1d DG |
828 | goto error; |
829 | } | |
830 | ||
831 | DBG("Kernel session started"); | |
832 | ||
833 | return 0; | |
834 | ||
835 | error: | |
836 | return ret; | |
837 | } | |
838 | ||
f3ed775e | 839 | /* |
050349bb | 840 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e DG |
841 | */ |
842 | void kernel_wait_quiescent(int fd) | |
843 | { | |
844 | int ret; | |
845 | ||
846 | DBG("Kernel quiescent wait on %d", fd); | |
847 | ||
848 | ret = kernctl_wait_quiescent(fd); | |
849 | if (ret < 0) { | |
df0f840b | 850 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
851 | ERR("Kernel quiescent wait failed"); |
852 | } | |
853 | } | |
854 | ||
855 | /* | |
f3ed775e DG |
856 | * Force flush buffer of metadata. |
857 | */ | |
858 | int kernel_metadata_flush_buffer(int fd) | |
859 | { | |
860 | int ret; | |
861 | ||
169d2cb7 DG |
862 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
863 | ||
f3ed775e DG |
864 | ret = kernctl_buffer_flush(fd); |
865 | if (ret < 0) { | |
00e2e675 | 866 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
867 | } |
868 | ||
869 | return 0; | |
870 | } | |
871 | ||
872 | /* | |
050349bb | 873 | * Force flush buffer for channel. |
f3ed775e DG |
874 | */ |
875 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
876 | { | |
877 | int ret; | |
878 | struct ltt_kernel_stream *stream; | |
879 | ||
0525e9ae DG |
880 | assert(channel); |
881 | ||
f3ed775e DG |
882 | DBG("Flush buffer for channel %s", channel->channel->name); |
883 | ||
884 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
885 | DBG("Flushing channel stream %d", stream->fd); | |
886 | ret = kernctl_buffer_flush(stream->fd); | |
887 | if (ret < 0) { | |
df0f840b | 888 | PERROR("ioctl"); |
f3ed775e DG |
889 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
890 | stream->fd, ret); | |
891 | } | |
892 | } | |
893 | ||
894 | return 0; | |
895 | } | |
896 | ||
8c0faa1d | 897 | /* |
050349bb | 898 | * Stop tracing session. |
8c0faa1d DG |
899 | */ |
900 | int kernel_stop_session(struct ltt_kernel_session *session) | |
901 | { | |
902 | int ret; | |
903 | ||
0525e9ae DG |
904 | assert(session); |
905 | ||
8c0faa1d DG |
906 | ret = kernctl_stop_session(session->fd); |
907 | if (ret < 0) { | |
908 | goto error; | |
909 | } | |
910 | ||
911 | DBG("Kernel session stopped"); | |
912 | ||
913 | return 0; | |
914 | ||
915 | error: | |
916 | return ret; | |
917 | } | |
918 | ||
919 | /* | |
050349bb DG |
920 | * Open stream of channel, register it to the kernel tracer and add it |
921 | * to the stream list of the channel. | |
8c0faa1d | 922 | * |
1cfb4b98 MD |
923 | * Note: given that the streams may appear in random order wrt CPU |
924 | * number (e.g. cpu hotplug), the index value of the stream number in | |
925 | * the stream name is not necessarily linked to the CPU number. | |
926 | * | |
050349bb | 927 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 928 | */ |
f3ed775e | 929 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 930 | { |
1cfb4b98 | 931 | int ret; |
8c0faa1d DG |
932 | struct ltt_kernel_stream *lks; |
933 | ||
0525e9ae DG |
934 | assert(channel); |
935 | ||
5a47c6a2 | 936 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
937 | lks = trace_kernel_create_stream(channel->channel->name, |
938 | channel->stream_count); | |
8c0faa1d | 939 | if (lks == NULL) { |
799e2c4f MD |
940 | ret = close(ret); |
941 | if (ret) { | |
942 | PERROR("close"); | |
943 | } | |
8c0faa1d DG |
944 | goto error; |
945 | } | |
946 | ||
947 | lks->fd = ret; | |
7b395890 DG |
948 | /* Prevent fd duplication after execlp() */ |
949 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
950 | if (ret < 0) { | |
df0f840b | 951 | PERROR("fcntl session fd"); |
7b395890 DG |
952 | } |
953 | ||
1624d5b7 JD |
954 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
955 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
956 | ||
1cfb4b98 | 957 | /* Add stream to channel stream list */ |
8c0faa1d DG |
958 | cds_list_add(&lks->list, &channel->stream_list.head); |
959 | channel->stream_count++; | |
8c0faa1d | 960 | |
00e2e675 DG |
961 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
962 | lks->state); | |
54012638 | 963 | } |
8c0faa1d DG |
964 | |
965 | return channel->stream_count; | |
966 | ||
967 | error: | |
54012638 | 968 | return -1; |
8c0faa1d DG |
969 | } |
970 | ||
971 | /* | |
050349bb | 972 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 973 | */ |
f3ed775e | 974 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
975 | { |
976 | int ret; | |
977 | ||
0525e9ae DG |
978 | assert(session); |
979 | ||
8c0faa1d DG |
980 | ret = kernctl_create_stream(session->metadata->fd); |
981 | if (ret < 0) { | |
df0f840b | 982 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
983 | goto error; |
984 | } | |
985 | ||
986 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
987 | session->metadata_stream_fd = ret; | |
7b395890 DG |
988 | /* Prevent fd duplication after execlp() */ |
989 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
990 | if (ret < 0) { | |
df0f840b | 991 | PERROR("fcntl session fd"); |
7b395890 | 992 | } |
aaf26714 DG |
993 | |
994 | return 0; | |
995 | ||
996 | error: | |
54012638 | 997 | return -1; |
aaf26714 | 998 | } |
2ef84c95 DG |
999 | |
1000 | /* | |
9f19cc17 | 1001 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 1002 | */ |
9f19cc17 | 1003 | ssize_t kernel_list_events(int tracer_fd, struct lttng_event **events) |
2ef84c95 | 1004 | { |
53efb85a | 1005 | int fd, ret; |
9f19cc17 DG |
1006 | char *event; |
1007 | size_t nbmem, count = 0; | |
2ef84c95 | 1008 | FILE *fp; |
9f19cc17 | 1009 | struct lttng_event *elist; |
2ef84c95 | 1010 | |
0525e9ae DG |
1011 | assert(events); |
1012 | ||
2ef84c95 DG |
1013 | fd = kernctl_tracepoint_list(tracer_fd); |
1014 | if (fd < 0) { | |
df0f840b | 1015 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
1016 | goto error; |
1017 | } | |
1018 | ||
1019 | fp = fdopen(fd, "r"); | |
1020 | if (fp == NULL) { | |
df0f840b | 1021 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 1022 | goto error_fp; |
2ef84c95 DG |
1023 | } |
1024 | ||
1025 | /* | |
1026 | * Init memory size counter | |
1027 | * See kernel-ctl.h for explanation of this value | |
1028 | */ | |
6725fe19 | 1029 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
ba7f0ae5 | 1030 | elist = zmalloc(sizeof(struct lttng_event) * nbmem); |
3b870559 MD |
1031 | if (elist == NULL) { |
1032 | PERROR("alloc list events"); | |
1033 | count = -ENOMEM; | |
1034 | goto end; | |
1035 | } | |
2ef84c95 | 1036 | |
53efb85a | 1037 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 1038 | if (count >= nbmem) { |
3b870559 | 1039 | struct lttng_event *new_elist; |
53efb85a | 1040 | size_t new_nbmem; |
3b870559 | 1041 | |
53efb85a MD |
1042 | new_nbmem = nbmem << 1; |
1043 | DBG("Reallocating event list from %zu to %zu bytes", | |
1044 | nbmem, new_nbmem); | |
1045 | new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event)); | |
3b870559 | 1046 | if (new_elist == NULL) { |
df0f840b | 1047 | PERROR("realloc list events"); |
3b870559 MD |
1048 | free(event); |
1049 | free(elist); | |
61b73b12 MD |
1050 | count = -ENOMEM; |
1051 | goto end; | |
2ef84c95 | 1052 | } |
53efb85a MD |
1053 | /* Zero the new memory */ |
1054 | memset(new_elist + nbmem, 0, | |
1055 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
1056 | nbmem = new_nbmem; | |
3b870559 | 1057 | elist = new_elist; |
2ef84c95 | 1058 | } |
99497cd0 MD |
1059 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
1060 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 1061 | elist[count].enabled = -1; |
9f19cc17 | 1062 | count++; |
3b870559 | 1063 | free(event); |
2ef84c95 DG |
1064 | } |
1065 | ||
9f19cc17 | 1066 | *events = elist; |
ced2f820 | 1067 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 1068 | end: |
799e2c4f MD |
1069 | ret = fclose(fp); /* closes both fp and fd */ |
1070 | if (ret) { | |
1071 | PERROR("fclose"); | |
1072 | } | |
9f19cc17 | 1073 | return count; |
2ef84c95 | 1074 | |
61b73b12 | 1075 | error_fp: |
799e2c4f MD |
1076 | ret = close(fd); |
1077 | if (ret) { | |
1078 | PERROR("close"); | |
1079 | } | |
2ef84c95 DG |
1080 | error: |
1081 | return -1; | |
1082 | } | |
096102bd DG |
1083 | |
1084 | /* | |
1085 | * Get kernel version and validate it. | |
1086 | */ | |
88076e89 JD |
1087 | int kernel_validate_version(int tracer_fd, |
1088 | struct lttng_kernel_tracer_version *version, | |
1089 | struct lttng_kernel_tracer_abi_version *abi_version) | |
096102bd DG |
1090 | { |
1091 | int ret; | |
096102bd | 1092 | |
88076e89 | 1093 | ret = kernctl_tracer_version(tracer_fd, version); |
096102bd | 1094 | if (ret < 0) { |
521dd134 | 1095 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
1096 | goto error; |
1097 | } | |
1098 | ||
1099 | /* Validate version */ | |
88076e89 | 1100 | if (version->major != VERSION_MAJOR) { |
c052142c | 1101 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", |
88076e89 | 1102 | version->major, VERSION_MAJOR); |
096102bd | 1103 | goto error_version; |
096102bd | 1104 | } |
88076e89 | 1105 | ret = kernctl_tracer_abi_version(tracer_fd, abi_version); |
c052142c | 1106 | if (ret < 0) { |
521dd134 | 1107 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
1108 | goto error; |
1109 | } | |
88076e89 | 1110 | if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) { |
521dd134 | 1111 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
88076e89 | 1112 | abi_version->major, abi_version->minor, |
c052142c MD |
1113 | LTTNG_MODULES_ABI_MAJOR_VERSION); |
1114 | goto error; | |
1115 | } | |
1116 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
88076e89 JD |
1117 | version->major, version->minor, |
1118 | abi_version->major, abi_version->minor); | |
096102bd DG |
1119 | return 0; |
1120 | ||
1121 | error_version: | |
096102bd DG |
1122 | ret = -1; |
1123 | ||
1124 | error: | |
521dd134 | 1125 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
1126 | return ret; |
1127 | } | |
335a95b7 MD |
1128 | |
1129 | /* | |
1130 | * Kernel work-arounds called at the start of sessiond main(). | |
1131 | */ | |
1132 | int init_kernel_workarounds(void) | |
1133 | { | |
8936c33a | 1134 | int ret; |
335a95b7 MD |
1135 | FILE *fp; |
1136 | ||
1137 | /* | |
1138 | * boot_id needs to be read once before being used concurrently | |
1139 | * to deal with a Linux kernel race. A fix is proposed for | |
1140 | * upstream, but the work-around is needed for older kernels. | |
1141 | */ | |
1142 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
1143 | if (!fp) { | |
1144 | goto end_boot_id; | |
1145 | } | |
1146 | while (!feof(fp)) { | |
1147 | char buf[37] = ""; | |
1148 | ||
8936c33a DG |
1149 | ret = fread(buf, 1, sizeof(buf), fp); |
1150 | if (ret < 0) { | |
1151 | /* Ignore error, we don't really care */ | |
1152 | } | |
335a95b7 | 1153 | } |
799e2c4f MD |
1154 | ret = fclose(fp); |
1155 | if (ret) { | |
1156 | PERROR("fclose"); | |
1157 | } | |
335a95b7 | 1158 | end_boot_id: |
335a95b7 MD |
1159 | return 0; |
1160 | } | |
2f77fc4b DG |
1161 | |
1162 | /* | |
1163 | * Complete teardown of a kernel session. | |
1164 | */ | |
1165 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
1166 | { | |
1167 | if (ksess == NULL) { | |
1168 | DBG3("No kernel session when tearing down session"); | |
1169 | return; | |
1170 | } | |
1171 | ||
1172 | DBG("Tearing down kernel session"); | |
1173 | ||
07b86b52 | 1174 | /* |
15dc512a DG |
1175 | * Destroy channels on the consumer if at least one FD has been sent and we |
1176 | * are in no output mode because the streams are in *no* monitor mode so we | |
1177 | * have to send a command to clean them up or else they leaked. | |
07b86b52 | 1178 | */ |
15dc512a | 1179 | if (!ksess->output_traces && ksess->consumer_fds_sent) { |
07b86b52 JD |
1180 | int ret; |
1181 | struct consumer_socket *socket; | |
1182 | struct lttng_ht_iter iter; | |
1183 | ||
1184 | /* For each consumer socket. */ | |
d069d577 | 1185 | rcu_read_lock(); |
07b86b52 JD |
1186 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, |
1187 | socket, node.node) { | |
1188 | struct ltt_kernel_channel *chan; | |
1189 | ||
1190 | /* For each channel, ask the consumer to destroy it. */ | |
1191 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1192 | ret = kernel_consumer_destroy_channel(socket, chan); | |
1193 | if (ret < 0) { | |
1194 | /* Consumer is probably dead. Use next socket. */ | |
1195 | continue; | |
1196 | } | |
1197 | } | |
1198 | } | |
d069d577 | 1199 | rcu_read_unlock(); |
07b86b52 JD |
1200 | } |
1201 | ||
2f77fc4b DG |
1202 | /* Close any relayd session */ |
1203 | consumer_output_send_destroy_relayd(ksess->consumer); | |
1204 | ||
1205 | trace_kernel_destroy_session(ksess); | |
1206 | } | |
fb5f35b6 DG |
1207 | |
1208 | /* | |
1209 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
1210 | */ | |
1211 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
1212 | { | |
1213 | struct ltt_kernel_session *ksess = NULL; | |
1214 | ||
1215 | assert(kchan); | |
1216 | assert(kchan->channel); | |
1217 | ||
1218 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
1219 | ||
1220 | /* Update channel count of associated session. */ | |
1221 | if (kchan->session) { | |
1222 | /* Keep pointer reference so we can update it after the destroy. */ | |
1223 | ksess = kchan->session; | |
1224 | } | |
1225 | ||
1226 | trace_kernel_destroy_channel(kchan); | |
1227 | ||
1228 | /* | |
1229 | * At this point the kernel channel is not visible anymore. This is safe | |
1230 | * since in order to work on a visible kernel session, the tracing session | |
1231 | * lock (ltt_session.lock) MUST be acquired. | |
1232 | */ | |
1233 | if (ksess) { | |
1234 | ksess->channel_count--; | |
1235 | } | |
1236 | } | |
6dc3064a DG |
1237 | |
1238 | /* | |
1239 | * Take a snapshot for a given kernel session. | |
1240 | * | |
9a654598 | 1241 | * Return LTTNG_OK on success or else return a LTTNG_ERR code. |
6dc3064a | 1242 | */ |
9a654598 | 1243 | enum lttng_error_code kernel_snapshot_record(struct ltt_kernel_session *ksess, |
d07ceecd MD |
1244 | struct snapshot_output *output, int wait, |
1245 | uint64_t nb_packets_per_stream) | |
6dc3064a | 1246 | { |
2a06df8d | 1247 | int err, ret, saved_metadata_fd; |
9a654598 | 1248 | enum lttng_error_code status = LTTNG_OK; |
6dc3064a DG |
1249 | struct consumer_socket *socket; |
1250 | struct lttng_ht_iter iter; | |
1251 | struct ltt_kernel_metadata *saved_metadata; | |
e32d7f27 | 1252 | struct ltt_session *session = NULL; |
e098433c | 1253 | uint64_t trace_archive_id; |
6dc3064a DG |
1254 | |
1255 | assert(ksess); | |
1256 | assert(ksess->consumer); | |
1257 | assert(output); | |
1258 | ||
1259 | DBG("Kernel snapshot record started"); | |
1260 | ||
e098433c JG |
1261 | session = session_find_by_id(ksess->id); |
1262 | assert(session); | |
1263 | assert(pthread_mutex_trylock(&session->lock)); | |
1264 | assert(session_trylock_list()); | |
1265 | trace_archive_id = session->current_archive_id; | |
1266 | ||
6dc3064a DG |
1267 | /* Save current metadata since the following calls will change it. */ |
1268 | saved_metadata = ksess->metadata; | |
1269 | saved_metadata_fd = ksess->metadata_stream_fd; | |
1270 | ||
1271 | rcu_read_lock(); | |
1272 | ||
1273 | ret = kernel_open_metadata(ksess); | |
1274 | if (ret < 0) { | |
9a654598 | 1275 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1276 | goto error; |
1277 | } | |
1278 | ||
1279 | ret = kernel_open_metadata_stream(ksess); | |
1280 | if (ret < 0) { | |
9a654598 | 1281 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1282 | goto error_open_stream; |
1283 | } | |
1284 | ||
1285 | /* Send metadata to consumer and snapshot everything. */ | |
1286 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1287 | socket, node.node) { | |
1288 | struct consumer_output *saved_output; | |
1289 | struct ltt_kernel_channel *chan; | |
6dc3064a DG |
1290 | |
1291 | /* | |
1292 | * Temporarly switch consumer output for our snapshot output. As long | |
1293 | * as the session lock is taken, this is safe. | |
1294 | */ | |
1295 | saved_output = ksess->consumer; | |
1296 | ksess->consumer = output->consumer; | |
1297 | ||
1298 | pthread_mutex_lock(socket->lock); | |
1299 | /* This stream must not be monitored by the consumer. */ | |
07b86b52 | 1300 | ret = kernel_consumer_add_metadata(socket, ksess, 0); |
6dc3064a | 1301 | pthread_mutex_unlock(socket->lock); |
07b86b52 | 1302 | /* Put back the saved consumer output into the session. */ |
6dc3064a DG |
1303 | ksess->consumer = saved_output; |
1304 | if (ret < 0) { | |
0ed78e50 | 1305 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1306 | goto error_consumer; |
1307 | } | |
1308 | ||
1309 | /* For each channel, ask the consumer to snapshot it. */ | |
1310 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
9a654598 | 1311 | status = consumer_snapshot_channel(socket, chan->key, output, 0, |
5c786ded JD |
1312 | ksess->uid, ksess->gid, |
1313 | DEFAULT_KERNEL_TRACE_DIR, wait, | |
e098433c JG |
1314 | nb_packets_per_stream, |
1315 | trace_archive_id); | |
9a654598 | 1316 | if (status != LTTNG_OK) { |
2a06df8d DG |
1317 | (void) kernel_consumer_destroy_metadata(socket, |
1318 | ksess->metadata); | |
6dc3064a DG |
1319 | goto error_consumer; |
1320 | } | |
1321 | } | |
1322 | ||
1323 | /* Snapshot metadata, */ | |
9a654598 | 1324 | status = consumer_snapshot_channel(socket, ksess->metadata->key, output, |
5c786ded | 1325 | 1, ksess->uid, ksess->gid, |
e098433c JG |
1326 | DEFAULT_KERNEL_TRACE_DIR, wait, 0, |
1327 | trace_archive_id); | |
9a654598 | 1328 | if (status != LTTNG_OK) { |
6dc3064a DG |
1329 | goto error_consumer; |
1330 | } | |
07b86b52 JD |
1331 | |
1332 | /* | |
1333 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1334 | * it's not monitored on the consumer side. | |
1335 | */ | |
1336 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1337 | } |
1338 | ||
1339 | error_consumer: | |
1340 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1341 | err = close(ksess->metadata_stream_fd); |
1342 | if (err < 0) { | |
6dc3064a DG |
1343 | PERROR("close snapshot kernel"); |
1344 | } | |
1345 | ||
1346 | error_open_stream: | |
1347 | trace_kernel_destroy_metadata(ksess->metadata); | |
1348 | error: | |
1349 | /* Restore metadata state.*/ | |
1350 | ksess->metadata = saved_metadata; | |
1351 | ksess->metadata_stream_fd = saved_metadata_fd; | |
e32d7f27 JG |
1352 | if (session) { |
1353 | session_put(session); | |
1354 | } | |
6dc3064a | 1355 | rcu_read_unlock(); |
9a654598 | 1356 | return status; |
6dc3064a | 1357 | } |
834978fd DG |
1358 | |
1359 | /* | |
1360 | * Get the syscall mask array from the kernel tracer. | |
1361 | * | |
1362 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1363 | * be freed. | |
1364 | */ | |
1365 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1366 | { | |
1367 | assert(syscall_mask); | |
1368 | assert(nr_bits); | |
1369 | ||
1370 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1371 | } | |
6e21424e JR |
1372 | |
1373 | /* | |
1374 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1375 | * version number. | |
1376 | * | |
1377 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1378 | * of errors. | |
1379 | */ | |
1380 | int kernel_supports_ring_buffer_snapshot_sample_positions(int tracer_fd) | |
1381 | { | |
1382 | int ret = 0; // Not supported by default | |
1383 | struct lttng_kernel_tracer_abi_version abi; | |
1384 | ||
1385 | ret = kernctl_tracer_abi_version(tracer_fd, &abi); | |
1386 | if (ret < 0) { | |
1387 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1388 | goto error; | |
1389 | } | |
1390 | ||
1391 | /* | |
1392 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1393 | */ | |
1394 | if (abi.major >= 2 && abi.minor >= 3) { | |
1395 | /* Supported */ | |
1396 | ret = 1; | |
1397 | } else { | |
1398 | /* Not supported */ | |
1399 | ret = 0; | |
1400 | } | |
1401 | error: | |
1402 | return ret; | |
1403 | } | |
5c408ad8 JD |
1404 | |
1405 | /* | |
1406 | * Rotate a kernel session. | |
1407 | * | |
d5a1b7aa | 1408 | * Return LTTNG_OK on success or else an LTTng error code. |
5c408ad8 | 1409 | */ |
d5a1b7aa | 1410 | enum lttng_error_code kernel_rotate_session(struct ltt_session *session) |
5c408ad8 JD |
1411 | { |
1412 | int ret; | |
d5a1b7aa | 1413 | enum lttng_error_code status = LTTNG_OK; |
5c408ad8 JD |
1414 | struct consumer_socket *socket; |
1415 | struct lttng_ht_iter iter; | |
1416 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1417 | ||
1418 | assert(ksess); | |
1419 | assert(ksess->consumer); | |
1420 | ||
1421 | DBG("Rotate kernel session %s started (session %" PRIu64 ")", | |
1422 | session->name, session->id); | |
1423 | ||
1424 | rcu_read_lock(); | |
1425 | ||
1426 | /* | |
1427 | * Note that this loop will end after one iteration given that there is | |
1428 | * only one kernel consumer. | |
1429 | */ | |
1430 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1431 | socket, node.node) { | |
1432 | struct ltt_kernel_channel *chan; | |
1433 | ||
5c408ad8 JD |
1434 | /* For each channel, ask the consumer to rotate it. */ |
1435 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
92816cc3 JG |
1436 | DBG("Rotate kernel channel %" PRIu64 ", session %s", |
1437 | chan->key, session->name); | |
5c408ad8 JD |
1438 | ret = consumer_rotate_channel(socket, chan->key, |
1439 | ksess->uid, ksess->gid, ksess->consumer, | |
b178f53e | 1440 | ksess->consumer->domain_subdir, |
5c408ad8 | 1441 | /* is_metadata_channel */ false, |
92816cc3 | 1442 | session->current_archive_id); |
5c408ad8 | 1443 | if (ret < 0) { |
d5a1b7aa | 1444 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1445 | goto error; |
1446 | } | |
1447 | } | |
1448 | ||
1449 | /* | |
1450 | * Rotate the metadata channel. | |
1451 | */ | |
22a1b931 | 1452 | ret = consumer_rotate_channel(socket, ksess->metadata->key, |
5c408ad8 | 1453 | ksess->uid, ksess->gid, ksess->consumer, |
b178f53e | 1454 | ksess->consumer->domain_subdir, |
5c408ad8 | 1455 | /* is_metadata_channel */ true, |
92816cc3 | 1456 | session->current_archive_id); |
5c408ad8 | 1457 | if (ret < 0) { |
d5a1b7aa | 1458 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1459 | goto error; |
1460 | } | |
1461 | } | |
1462 | ||
5c408ad8 JD |
1463 | error: |
1464 | rcu_read_unlock(); | |
d5a1b7aa | 1465 | return status; |
5c408ad8 | 1466 | } |