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