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> |
82b69413 | 27 | #include <common/trace-chunk.h> |
db758600 | 28 | #include <common/kernel-ctl/kernel-ctl.h> |
c052142c | 29 | #include <common/kernel-ctl/kernel-ioctl.h> |
42224349 | 30 | #include <common/sessiond-comm/sessiond-comm.h> |
1e307fab | 31 | |
2f77fc4b | 32 | #include "consumer.h" |
4771f025 | 33 | #include "kernel.h" |
6dc3064a | 34 | #include "kernel-consumer.h" |
096102bd | 35 | #include "kern-modules.h" |
834978fd | 36 | #include "utils.h" |
5c408ad8 | 37 | #include "rotate.h" |
20fe2104 | 38 | |
e1f3997a JD |
39 | /* |
40 | * Key used to reference a channel between the sessiond and the consumer. This | |
41 | * is only read and updated with the session_list lock held. | |
42 | */ | |
43 | static uint64_t next_kernel_channel_key; | |
44 | ||
410b78a0 FD |
45 | #include <lttng/userspace-probe.h> |
46 | #include <lttng/userspace-probe-internal.h> | |
d65106b1 | 47 | /* |
050349bb | 48 | * Add context on a kernel channel. |
df3c77c8 JG |
49 | * |
50 | * Assumes the ownership of ctx. | |
d65106b1 DG |
51 | */ |
52 | int kernel_add_channel_context(struct ltt_kernel_channel *chan, | |
645328ae | 53 | struct ltt_kernel_context *ctx) |
d65106b1 DG |
54 | { |
55 | int ret; | |
56 | ||
0525e9ae DG |
57 | assert(chan); |
58 | assert(ctx); | |
59 | ||
d65106b1 | 60 | DBG("Adding context to channel %s", chan->channel->name); |
645328ae | 61 | ret = kernctl_add_context(chan->fd, &ctx->ctx); |
d65106b1 | 62 | if (ret < 0) { |
32af2c95 | 63 | switch (-ret) { |
1ae5e83e JD |
64 | case ENOSYS: |
65 | /* Exists but not available for this kernel */ | |
66 | ret = LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE; | |
67 | goto error; | |
68 | case EEXIST: | |
b579acd9 DG |
69 | /* If EEXIST, we just ignore the error */ |
70 | ret = 0; | |
1ae5e83e JD |
71 | goto end; |
72 | default: | |
73 | PERROR("add context ioctl"); | |
74 | ret = LTTNG_ERR_KERN_CONTEXT_FAIL; | |
75 | goto error; | |
b579acd9 | 76 | } |
d65106b1 | 77 | } |
21ed98c1 | 78 | ret = 0; |
d65106b1 | 79 | |
1ae5e83e | 80 | end: |
645328ae | 81 | cds_list_add_tail(&ctx->list, &chan->ctx_list); |
ba985c3a | 82 | ctx->in_list = true; |
df3c77c8 | 83 | ctx = NULL; |
d65106b1 | 84 | error: |
df3c77c8 JG |
85 | if (ctx) { |
86 | trace_kernel_destroy_context(ctx); | |
87 | } | |
d65106b1 DG |
88 | return ret; |
89 | } | |
90 | ||
20fe2104 | 91 | /* |
050349bb DG |
92 | * Create a new kernel session, register it to the kernel tracer and add it to |
93 | * the session daemon session. | |
20fe2104 | 94 | */ |
8c0faa1d | 95 | int kernel_create_session(struct ltt_session *session, int tracer_fd) |
20fe2104 DG |
96 | { |
97 | int ret; | |
98 | struct ltt_kernel_session *lks; | |
99 | ||
0525e9ae DG |
100 | assert(session); |
101 | ||
54012638 | 102 | /* Allocate data structure */ |
dec56f6c | 103 | lks = trace_kernel_create_session(); |
20fe2104 | 104 | if (lks == NULL) { |
54012638 | 105 | ret = -1; |
20fe2104 DG |
106 | goto error; |
107 | } | |
108 | ||
54012638 | 109 | /* Kernel tracer session creation */ |
20fe2104 DG |
110 | ret = kernctl_create_session(tracer_fd); |
111 | if (ret < 0) { | |
df0f840b | 112 | PERROR("ioctl kernel create session"); |
20fe2104 DG |
113 | goto error; |
114 | } | |
115 | ||
20fe2104 | 116 | lks->fd = ret; |
7b395890 DG |
117 | /* Prevent fd duplication after execlp() */ |
118 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
119 | if (ret < 0) { | |
df0f840b | 120 | PERROR("fcntl session fd"); |
7b395890 DG |
121 | } |
122 | ||
53632229 | 123 | lks->id = session->id; |
3bd1e081 | 124 | lks->consumer_fds_sent = 0; |
8c0faa1d | 125 | session->kernel_session = lks; |
8c0faa1d DG |
126 | |
127 | DBG("Kernel session created (fd: %d)", lks->fd); | |
20fe2104 DG |
128 | |
129 | return 0; | |
130 | ||
131 | error: | |
5f62c685 DG |
132 | if (lks) { |
133 | trace_kernel_destroy_session(lks); | |
d070c424 | 134 | trace_kernel_free_session(lks); |
5f62c685 | 135 | } |
20fe2104 DG |
136 | return ret; |
137 | } | |
138 | ||
139 | /* | |
050349bb DG |
140 | * Create a kernel channel, register it to the kernel tracer and add it to the |
141 | * kernel session. | |
20fe2104 | 142 | */ |
050349bb | 143 | int kernel_create_channel(struct ltt_kernel_session *session, |
fdd9eb17 | 144 | struct lttng_channel *chan) |
20fe2104 DG |
145 | { |
146 | int ret; | |
147 | struct ltt_kernel_channel *lkc; | |
20fe2104 | 148 | |
0525e9ae DG |
149 | assert(session); |
150 | assert(chan); | |
0525e9ae | 151 | |
54012638 | 152 | /* Allocate kernel channel */ |
fdd9eb17 | 153 | lkc = trace_kernel_create_channel(chan); |
54012638 | 154 | if (lkc == NULL) { |
20fe2104 DG |
155 | goto error; |
156 | } | |
157 | ||
ecc48a90 | 158 | DBG3("Kernel create channel %s with attr: %d, %" PRIu64 ", %" PRIu64 ", %u, %u, %d, %d", |
fdd9eb17 | 159 | chan->name, lkc->channel->attr.overwrite, |
173af62f DG |
160 | lkc->channel->attr.subbuf_size, lkc->channel->attr.num_subbuf, |
161 | lkc->channel->attr.switch_timer_interval, lkc->channel->attr.read_timer_interval, | |
ecc48a90 | 162 | lkc->channel->attr.live_timer_interval, lkc->channel->attr.output); |
173af62f | 163 | |
54012638 | 164 | /* Kernel tracer channel creation */ |
f3ed775e | 165 | ret = kernctl_create_channel(session->fd, &lkc->channel->attr); |
20fe2104 | 166 | if (ret < 0) { |
df0f840b | 167 | PERROR("ioctl kernel create channel"); |
20fe2104 DG |
168 | goto error; |
169 | } | |
170 | ||
54012638 | 171 | /* Setup the channel fd */ |
20fe2104 | 172 | lkc->fd = ret; |
7b395890 DG |
173 | /* Prevent fd duplication after execlp() */ |
174 | ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC); | |
175 | if (ret < 0) { | |
df0f840b | 176 | PERROR("fcntl session fd"); |
7b395890 DG |
177 | } |
178 | ||
54012638 | 179 | /* Add channel to session */ |
8c0faa1d DG |
180 | cds_list_add(&lkc->list, &session->channel_list.head); |
181 | session->channel_count++; | |
fb5f35b6 | 182 | lkc->session = session; |
e1f3997a | 183 | lkc->key = ++next_kernel_channel_key; |
20fe2104 | 184 | |
e1f3997a JD |
185 | DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")", |
186 | lkc->channel->name, lkc->fd, lkc->key); | |
20fe2104 DG |
187 | |
188 | return 0; | |
189 | ||
190 | error: | |
5f62c685 DG |
191 | if (lkc) { |
192 | free(lkc->channel); | |
193 | free(lkc); | |
194 | } | |
54012638 | 195 | return -1; |
20fe2104 | 196 | } |
f34daff7 | 197 | |
410b78a0 FD |
198 | /* |
199 | * Compute the offset of the instrumentation byte in the binary based on the | |
200 | * function probe location using the ELF lookup method. | |
201 | * | |
202 | * Returns 0 on success and set the offset out parameter to the offset of the | |
203 | * elf symbol | |
204 | * Returns -1 on error | |
205 | */ | |
206 | static | |
207 | int extract_userspace_probe_offset_function_elf( | |
87597c2c | 208 | const struct lttng_userspace_probe_location *probe_location, |
410b78a0 FD |
209 | struct ltt_kernel_session *session, uint64_t *offset) |
210 | { | |
211 | int fd; | |
212 | int ret = 0; | |
213 | const char *symbol = NULL; | |
87597c2c | 214 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
215 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; |
216 | ||
410b78a0 FD |
217 | assert(lttng_userspace_probe_location_get_type(probe_location) == |
218 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_FUNCTION); | |
219 | ||
220 | lookup = lttng_userspace_probe_location_get_lookup_method( | |
221 | probe_location); | |
222 | if (!lookup) { | |
223 | ret = -1; | |
224 | goto end; | |
225 | } | |
226 | ||
227 | lookup_method_type = | |
228 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
229 | ||
230 | assert(lookup_method_type == | |
231 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF); | |
232 | ||
233 | symbol = lttng_userspace_probe_location_function_get_function_name( | |
234 | probe_location); | |
235 | if (!symbol) { | |
236 | ret = -1; | |
237 | goto end; | |
238 | } | |
239 | ||
240 | fd = lttng_userspace_probe_location_function_get_binary_fd(probe_location); | |
241 | if (fd < 0) { | |
242 | ret = -1; | |
243 | goto end; | |
244 | } | |
245 | ||
246 | ret = run_as_extract_elf_symbol_offset(fd, symbol, session->uid, | |
247 | session->gid, offset); | |
248 | if (ret < 0) { | |
249 | DBG("userspace probe offset calculation failed for " | |
250 | "function %s", symbol); | |
251 | goto end; | |
252 | } | |
253 | ||
254 | DBG("userspace probe elf offset for %s is 0x%jd", symbol, (intmax_t)(*offset)); | |
255 | end: | |
256 | return ret; | |
257 | } | |
258 | ||
259 | /* | |
260 | * Compute the offsets of the instrumentation bytes in the binary based on the | |
261 | * tracepoint probe location using the SDT lookup method. This function | |
262 | * allocates the offsets buffer, the caller must free it. | |
263 | * | |
264 | * Returns 0 on success and set the offset out parameter to the offsets of the | |
265 | * SDT tracepoint. | |
266 | * Returns -1 on error. | |
267 | */ | |
268 | static | |
269 | int extract_userspace_probe_offset_tracepoint_sdt( | |
87597c2c | 270 | const struct lttng_userspace_probe_location *probe_location, |
410b78a0 FD |
271 | struct ltt_kernel_session *session, uint64_t **offsets, |
272 | uint32_t *offsets_count) | |
273 | { | |
274 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; | |
87597c2c | 275 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
276 | const char *probe_name = NULL, *provider_name = NULL; |
277 | int ret = 0; | |
278 | int fd, i; | |
279 | ||
280 | assert(lttng_userspace_probe_location_get_type(probe_location) == | |
281 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_TRACEPOINT); | |
282 | ||
283 | lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); | |
284 | if (!lookup) { | |
285 | ret = -1; | |
286 | goto end; | |
287 | } | |
288 | ||
289 | lookup_method_type = | |
290 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
291 | ||
292 | assert(lookup_method_type == | |
293 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT); | |
294 | ||
295 | ||
296 | probe_name = lttng_userspace_probe_location_tracepoint_get_probe_name( | |
297 | probe_location); | |
298 | if (!probe_name) { | |
299 | ret = -1; | |
300 | goto end; | |
301 | } | |
302 | ||
303 | provider_name = lttng_userspace_probe_location_tracepoint_get_provider_name( | |
304 | probe_location); | |
305 | if (!provider_name) { | |
306 | ret = -1; | |
307 | goto end; | |
308 | } | |
309 | ||
310 | fd = lttng_userspace_probe_location_tracepoint_get_binary_fd(probe_location); | |
311 | if (fd < 0) { | |
312 | ret = -1; | |
313 | goto end; | |
314 | } | |
315 | ||
316 | ret = run_as_extract_sdt_probe_offsets(fd, provider_name, probe_name, | |
317 | session->uid, session->gid, offsets, offsets_count); | |
318 | if (ret < 0) { | |
319 | DBG("userspace probe offset calculation failed for sdt " | |
320 | "probe %s:%s", provider_name, probe_name); | |
321 | goto end; | |
322 | } | |
323 | ||
324 | if (*offsets_count == 0) { | |
325 | DBG("no userspace probe offset found"); | |
326 | goto end; | |
327 | } | |
328 | ||
329 | DBG("%u userspace probe SDT offsets found for %s:%s at:", | |
330 | *offsets_count, provider_name, probe_name); | |
331 | for (i = 0; i < *offsets_count; i++) { | |
332 | DBG("\t0x%jd", (intmax_t)((*offsets)[i])); | |
333 | } | |
334 | end: | |
335 | return ret; | |
336 | } | |
337 | ||
338 | /* | |
339 | * Extract the offsets of the instrumentation point for the different lookup | |
340 | * methods. | |
341 | */ | |
342 | static | |
343 | int userspace_probe_add_callsites(struct lttng_event *ev, | |
344 | struct ltt_kernel_session *session, int fd) | |
345 | { | |
87597c2c | 346 | const struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL; |
410b78a0 | 347 | enum lttng_userspace_probe_location_lookup_method_type type; |
87597c2c | 348 | const struct lttng_userspace_probe_location *location = NULL; |
410b78a0 FD |
349 | int ret; |
350 | ||
351 | assert(ev); | |
352 | assert(ev->type == LTTNG_EVENT_USERSPACE_PROBE); | |
353 | ||
354 | location = lttng_event_get_userspace_probe_location(ev); | |
355 | if (!location) { | |
356 | ret = -1; | |
357 | goto end; | |
358 | } | |
359 | lookup_method = | |
360 | lttng_userspace_probe_location_get_lookup_method(location); | |
361 | if (!lookup_method) { | |
362 | ret = -1; | |
363 | goto end; | |
364 | } | |
365 | ||
366 | type = lttng_userspace_probe_location_lookup_method_get_type(lookup_method); | |
367 | switch (type) { | |
368 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: | |
369 | { | |
370 | struct lttng_kernel_event_callsite callsite; | |
371 | uint64_t offset; | |
372 | ||
373 | ret = extract_userspace_probe_offset_function_elf(location, session, &offset); | |
374 | if (ret) { | |
375 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
376 | goto end; | |
377 | } | |
378 | ||
379 | callsite.u.uprobe.offset = offset; | |
380 | ret = kernctl_add_callsite(fd, &callsite); | |
381 | if (ret) { | |
382 | WARN("Adding callsite to userspace probe " | |
383 | "event %s failed.", ev->name); | |
384 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
385 | goto end; | |
386 | } | |
387 | break; | |
388 | } | |
389 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: | |
390 | { | |
391 | int i; | |
392 | uint64_t *offsets = NULL; | |
393 | uint32_t offsets_count; | |
394 | struct lttng_kernel_event_callsite callsite; | |
395 | ||
396 | /* | |
397 | * This call allocates the offsets buffer. This buffer must be freed | |
398 | * by the caller | |
399 | */ | |
400 | ret = extract_userspace_probe_offset_tracepoint_sdt(location, session, | |
401 | &offsets, &offsets_count); | |
402 | if (ret) { | |
403 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
404 | goto end; | |
405 | } | |
406 | for (i = 0; i < offsets_count; i++) { | |
407 | callsite.u.uprobe.offset = offsets[i]; | |
408 | ret = kernctl_add_callsite(fd, &callsite); | |
409 | if (ret) { | |
410 | WARN("Adding callsite to userspace probe " | |
411 | "event %s failed.", ev->name); | |
412 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
413 | free(offsets); | |
414 | goto end; | |
415 | } | |
416 | } | |
417 | free(offsets); | |
418 | break; | |
419 | } | |
420 | default: | |
421 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
422 | goto end; | |
423 | } | |
424 | end: | |
425 | return ret; | |
426 | } | |
427 | ||
f34daff7 | 428 | /* |
050349bb DG |
429 | * Create a kernel event, enable it to the kernel tracer and add it to the |
430 | * channel event list of the kernel session. | |
49d21f93 | 431 | * We own filter_expression and filter. |
f34daff7 | 432 | */ |
050349bb | 433 | int kernel_create_event(struct lttng_event *ev, |
00a62084 MD |
434 | struct ltt_kernel_channel *channel, |
435 | char *filter_expression, | |
436 | struct lttng_filter_bytecode *filter) | |
f34daff7 | 437 | { |
71a3bb01 FD |
438 | int err, fd; |
439 | enum lttng_error_code ret; | |
f34daff7 | 440 | struct ltt_kernel_event *event; |
f34daff7 | 441 | |
0525e9ae DG |
442 | assert(ev); |
443 | assert(channel); | |
444 | ||
a969e101 | 445 | /* We pass ownership of filter_expression and filter */ |
71a3bb01 FD |
446 | ret = trace_kernel_create_event(ev, filter_expression, |
447 | filter, &event); | |
448 | if (ret != LTTNG_OK) { | |
f34daff7 DG |
449 | goto error; |
450 | } | |
451 | ||
71a3bb01 FD |
452 | fd = kernctl_create_event(channel->fd, event->event); |
453 | if (fd < 0) { | |
454 | switch (-fd) { | |
bd29c13d | 455 | case EEXIST: |
71a3bb01 | 456 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
bd29c13d DG |
457 | break; |
458 | case ENOSYS: | |
459 | WARN("Event type not implemented"); | |
71a3bb01 | 460 | ret = LTTNG_ERR_KERN_EVENT_ENOSYS; |
bd29c13d | 461 | break; |
8197a339 DG |
462 | case ENOENT: |
463 | WARN("Event %s not found!", ev->name); | |
71a3bb01 | 464 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
8197a339 | 465 | break; |
bd29c13d | 466 | default: |
71a3bb01 | 467 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
d87bfb32 DG |
468 | PERROR("create event ioctl"); |
469 | } | |
e953ef25 | 470 | goto free_event; |
8c0faa1d | 471 | } |
f34daff7 | 472 | |
d0ae4ea8 | 473 | event->type = ev->type; |
71a3bb01 | 474 | event->fd = fd; |
7b395890 | 475 | /* Prevent fd duplication after execlp() */ |
71a3bb01 FD |
476 | err = fcntl(event->fd, F_SETFD, FD_CLOEXEC); |
477 | if (err < 0) { | |
df0f840b | 478 | PERROR("fcntl session fd"); |
7b395890 DG |
479 | } |
480 | ||
00a62084 | 481 | if (filter) { |
71a3bb01 FD |
482 | err = kernctl_filter(event->fd, filter); |
483 | if (err < 0) { | |
484 | switch (-err) { | |
485 | case ENOMEM: | |
486 | ret = LTTNG_ERR_FILTER_NOMEM; | |
487 | break; | |
488 | default: | |
489 | ret = LTTNG_ERR_FILTER_INVAL; | |
490 | break; | |
491 | } | |
00a62084 MD |
492 | goto filter_error; |
493 | } | |
494 | } | |
495 | ||
dcabc190 FD |
496 | if (ev->type == LTTNG_EVENT_USERSPACE_PROBE) { |
497 | ret = userspace_probe_add_callsites(ev, channel->session, event->fd); | |
498 | if (ret) { | |
499 | goto add_callsite_error; | |
500 | } | |
501 | } | |
502 | ||
71a3bb01 FD |
503 | err = kernctl_enable(event->fd); |
504 | if (err < 0) { | |
505 | switch (-err) { | |
00a62084 MD |
506 | case EEXIST: |
507 | ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
508 | break; | |
509 | default: | |
510 | PERROR("enable kernel event"); | |
71a3bb01 | 511 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
00a62084 MD |
512 | break; |
513 | } | |
514 | goto enable_error; | |
515 | } | |
516 | ||
f3ed775e DG |
517 | /* Add event to event list */ |
518 | cds_list_add(&event->list, &channel->events_list.head); | |
cbbbb275 DG |
519 | channel->event_count++; |
520 | ||
e953ef25 DG |
521 | DBG("Event %s created (fd: %d)", ev->name, event->fd); |
522 | ||
523 | return 0; | |
524 | ||
dcabc190 | 525 | add_callsite_error: |
00a62084 MD |
526 | enable_error: |
527 | filter_error: | |
528 | { | |
529 | int closeret; | |
530 | ||
531 | closeret = close(event->fd); | |
532 | if (closeret) { | |
533 | PERROR("close event fd"); | |
534 | } | |
535 | } | |
e953ef25 DG |
536 | free_event: |
537 | free(event); | |
538 | error: | |
d87bfb32 | 539 | return ret; |
e953ef25 DG |
540 | } |
541 | ||
26cc6b4e | 542 | /* |
050349bb | 543 | * Disable a kernel channel. |
26cc6b4e DG |
544 | */ |
545 | int kernel_disable_channel(struct ltt_kernel_channel *chan) | |
546 | { | |
547 | int ret; | |
548 | ||
0525e9ae DG |
549 | assert(chan); |
550 | ||
26cc6b4e DG |
551 | ret = kernctl_disable(chan->fd); |
552 | if (ret < 0) { | |
df0f840b | 553 | PERROR("disable chan ioctl"); |
26cc6b4e DG |
554 | goto error; |
555 | } | |
556 | ||
557 | chan->enabled = 0; | |
e1f3997a JD |
558 | DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")", |
559 | chan->channel->name, chan->fd, chan->key); | |
26cc6b4e DG |
560 | |
561 | return 0; | |
562 | ||
563 | error: | |
564 | return ret; | |
565 | } | |
566 | ||
d36b8583 | 567 | /* |
050349bb | 568 | * Enable a kernel channel. |
d36b8583 DG |
569 | */ |
570 | int kernel_enable_channel(struct ltt_kernel_channel *chan) | |
571 | { | |
572 | int ret; | |
573 | ||
0525e9ae DG |
574 | assert(chan); |
575 | ||
d36b8583 | 576 | ret = kernctl_enable(chan->fd); |
32af2c95 | 577 | if (ret < 0 && ret != -EEXIST) { |
df0f840b | 578 | PERROR("Enable kernel chan"); |
d36b8583 DG |
579 | goto error; |
580 | } | |
581 | ||
582 | chan->enabled = 1; | |
e1f3997a JD |
583 | DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")", |
584 | chan->channel->name, chan->fd, chan->key); | |
d36b8583 DG |
585 | |
586 | return 0; | |
587 | ||
588 | error: | |
589 | return ret; | |
590 | } | |
591 | ||
19e70852 | 592 | /* |
050349bb | 593 | * Enable a kernel event. |
19e70852 DG |
594 | */ |
595 | int kernel_enable_event(struct ltt_kernel_event *event) | |
596 | { | |
597 | int ret; | |
598 | ||
0525e9ae DG |
599 | assert(event); |
600 | ||
19e70852 | 601 | ret = kernctl_enable(event->fd); |
42224349 | 602 | if (ret < 0) { |
32af2c95 | 603 | switch (-ret) { |
42224349 | 604 | case EEXIST: |
f73fabfd | 605 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
606 | break; |
607 | default: | |
608 | PERROR("enable kernel event"); | |
609 | break; | |
610 | } | |
19e70852 DG |
611 | goto error; |
612 | } | |
613 | ||
614 | event->enabled = 1; | |
615 | DBG("Kernel event %s enabled (fd: %d)", event->event->name, event->fd); | |
616 | ||
617 | return 0; | |
618 | ||
619 | error: | |
d36b8583 | 620 | return ret; |
19e70852 DG |
621 | } |
622 | ||
e953ef25 | 623 | /* |
050349bb | 624 | * Disable a kernel event. |
e953ef25 | 625 | */ |
19e70852 | 626 | int kernel_disable_event(struct ltt_kernel_event *event) |
e953ef25 DG |
627 | { |
628 | int ret; | |
19e70852 | 629 | |
0525e9ae DG |
630 | assert(event); |
631 | ||
19e70852 | 632 | ret = kernctl_disable(event->fd); |
42224349 | 633 | if (ret < 0) { |
32af2c95 | 634 | switch (-ret) { |
42224349 | 635 | case EEXIST: |
f73fabfd | 636 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
637 | break; |
638 | default: | |
639 | PERROR("disable kernel event"); | |
640 | break; | |
641 | } | |
19e70852 | 642 | goto error; |
e953ef25 | 643 | } |
f3ed775e | 644 | |
19e70852 DG |
645 | event->enabled = 0; |
646 | DBG("Kernel event %s disabled (fd: %d)", event->event->name, event->fd); | |
647 | ||
f34daff7 DG |
648 | return 0; |
649 | ||
650 | error: | |
d36b8583 | 651 | return ret; |
f34daff7 | 652 | } |
aaf26714 | 653 | |
6e911cad | 654 | |
ccf10263 MD |
655 | int kernel_track_pid(struct ltt_kernel_session *session, int pid) |
656 | { | |
7c493d31 MD |
657 | int ret; |
658 | ||
ccf10263 MD |
659 | DBG("Kernel track PID %d for session id %" PRIu64 ".", |
660 | pid, session->id); | |
7c493d31 MD |
661 | ret = kernctl_track_pid(session->fd, pid); |
662 | if (!ret) { | |
663 | return LTTNG_OK; | |
664 | } | |
32af2c95 | 665 | switch (-ret) { |
7c493d31 MD |
666 | case EINVAL: |
667 | return LTTNG_ERR_INVALID; | |
668 | case ENOMEM: | |
669 | return LTTNG_ERR_NOMEM; | |
670 | case EEXIST: | |
671 | return LTTNG_ERR_PID_TRACKED; | |
672 | default: | |
673 | return LTTNG_ERR_UNK; | |
674 | } | |
ccf10263 MD |
675 | } |
676 | ||
677 | int kernel_untrack_pid(struct ltt_kernel_session *session, int pid) | |
678 | { | |
7c493d31 MD |
679 | int ret; |
680 | ||
ccf10263 MD |
681 | DBG("Kernel untrack PID %d for session id %" PRIu64 ".", |
682 | pid, session->id); | |
7c493d31 MD |
683 | ret = kernctl_untrack_pid(session->fd, pid); |
684 | if (!ret) { | |
685 | return LTTNG_OK; | |
686 | } | |
32af2c95 | 687 | switch (-ret) { |
7c493d31 MD |
688 | case EINVAL: |
689 | return LTTNG_ERR_INVALID; | |
690 | case ENOMEM: | |
691 | return LTTNG_ERR_NOMEM; | |
692 | case ENOENT: | |
693 | return LTTNG_ERR_PID_NOT_TRACKED; | |
694 | default: | |
695 | return LTTNG_ERR_UNK; | |
696 | } | |
ccf10263 MD |
697 | } |
698 | ||
a5dfbb9d MD |
699 | ssize_t kernel_list_tracker_pids(struct ltt_kernel_session *session, |
700 | int **_pids) | |
701 | { | |
702 | int fd, ret; | |
703 | int pid; | |
704 | ssize_t nbmem, count = 0; | |
705 | FILE *fp; | |
706 | int *pids; | |
707 | ||
708 | fd = kernctl_list_tracker_pids(session->fd); | |
709 | if (fd < 0) { | |
710 | PERROR("kernel tracker pids list"); | |
711 | goto error; | |
712 | } | |
713 | ||
714 | fp = fdopen(fd, "r"); | |
715 | if (fp == NULL) { | |
716 | PERROR("kernel tracker pids list fdopen"); | |
717 | goto error_fp; | |
718 | } | |
719 | ||
720 | nbmem = KERNEL_TRACKER_PIDS_INIT_LIST_SIZE; | |
721 | pids = zmalloc(sizeof(*pids) * nbmem); | |
722 | if (pids == NULL) { | |
723 | PERROR("alloc list pids"); | |
724 | count = -ENOMEM; | |
725 | goto end; | |
726 | } | |
727 | ||
728 | while (fscanf(fp, "process { pid = %u; };\n", &pid) == 1) { | |
729 | if (count >= nbmem) { | |
730 | int *new_pids; | |
731 | size_t new_nbmem; | |
732 | ||
733 | new_nbmem = nbmem << 1; | |
734 | DBG("Reallocating pids list from %zu to %zu entries", | |
735 | nbmem, new_nbmem); | |
736 | new_pids = realloc(pids, new_nbmem * sizeof(*new_pids)); | |
737 | if (new_pids == NULL) { | |
738 | PERROR("realloc list events"); | |
739 | free(pids); | |
740 | count = -ENOMEM; | |
741 | goto end; | |
742 | } | |
743 | /* Zero the new memory */ | |
744 | memset(new_pids + nbmem, 0, | |
745 | (new_nbmem - nbmem) * sizeof(*new_pids)); | |
746 | nbmem = new_nbmem; | |
747 | pids = new_pids; | |
748 | } | |
749 | pids[count++] = pid; | |
750 | } | |
751 | ||
752 | *_pids = pids; | |
753 | DBG("Kernel list tracker pids done (%zd pids)", count); | |
754 | end: | |
755 | ret = fclose(fp); /* closes both fp and fd */ | |
756 | if (ret) { | |
757 | PERROR("fclose"); | |
758 | } | |
759 | return count; | |
760 | ||
761 | error_fp: | |
762 | ret = close(fd); | |
763 | if (ret) { | |
764 | PERROR("close"); | |
765 | } | |
766 | error: | |
767 | return -1; | |
768 | } | |
769 | ||
aaf26714 | 770 | /* |
050349bb DG |
771 | * Create kernel metadata, open from the kernel tracer and add it to the |
772 | * kernel session. | |
aaf26714 | 773 | */ |
a4b92340 | 774 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
775 | { |
776 | int ret; | |
74024a21 | 777 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 778 | |
0525e9ae DG |
779 | assert(session); |
780 | ||
54012638 | 781 | /* Allocate kernel metadata */ |
a4b92340 | 782 | lkm = trace_kernel_create_metadata(); |
54012638 | 783 | if (lkm == NULL) { |
aaf26714 DG |
784 | goto error; |
785 | } | |
786 | ||
54012638 | 787 | /* Kernel tracer metadata creation */ |
f3ed775e | 788 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 789 | if (ret < 0) { |
74024a21 | 790 | goto error_open; |
aaf26714 DG |
791 | } |
792 | ||
8c0faa1d | 793 | lkm->fd = ret; |
d40f0359 | 794 | lkm->key = ++next_kernel_channel_key; |
7b395890 DG |
795 | /* Prevent fd duplication after execlp() */ |
796 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
797 | if (ret < 0) { | |
df0f840b | 798 | PERROR("fcntl session fd"); |
7b395890 DG |
799 | } |
800 | ||
aaf26714 | 801 | session->metadata = lkm; |
8c0faa1d | 802 | |
00e2e675 | 803 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
804 | |
805 | return 0; | |
806 | ||
74024a21 DG |
807 | error_open: |
808 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 809 | error: |
54012638 | 810 | return -1; |
8c0faa1d DG |
811 | } |
812 | ||
813 | /* | |
050349bb | 814 | * Start tracing session. |
8c0faa1d DG |
815 | */ |
816 | int kernel_start_session(struct ltt_kernel_session *session) | |
817 | { | |
818 | int ret; | |
819 | ||
0525e9ae DG |
820 | assert(session); |
821 | ||
8c0faa1d DG |
822 | ret = kernctl_start_session(session->fd); |
823 | if (ret < 0) { | |
df0f840b | 824 | PERROR("ioctl start session"); |
8c0faa1d DG |
825 | goto error; |
826 | } | |
827 | ||
828 | DBG("Kernel session started"); | |
829 | ||
830 | return 0; | |
831 | ||
832 | error: | |
833 | return ret; | |
834 | } | |
835 | ||
f3ed775e | 836 | /* |
050349bb | 837 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e DG |
838 | */ |
839 | void kernel_wait_quiescent(int fd) | |
840 | { | |
841 | int ret; | |
842 | ||
843 | DBG("Kernel quiescent wait on %d", fd); | |
844 | ||
845 | ret = kernctl_wait_quiescent(fd); | |
846 | if (ret < 0) { | |
df0f840b | 847 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
848 | ERR("Kernel quiescent wait failed"); |
849 | } | |
850 | } | |
851 | ||
852 | /* | |
f3ed775e DG |
853 | * Force flush buffer of metadata. |
854 | */ | |
855 | int kernel_metadata_flush_buffer(int fd) | |
856 | { | |
857 | int ret; | |
858 | ||
169d2cb7 DG |
859 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
860 | ||
f3ed775e DG |
861 | ret = kernctl_buffer_flush(fd); |
862 | if (ret < 0) { | |
00e2e675 | 863 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
864 | } |
865 | ||
866 | return 0; | |
867 | } | |
868 | ||
869 | /* | |
050349bb | 870 | * Force flush buffer for channel. |
f3ed775e DG |
871 | */ |
872 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
873 | { | |
874 | int ret; | |
875 | struct ltt_kernel_stream *stream; | |
876 | ||
0525e9ae DG |
877 | assert(channel); |
878 | ||
f3ed775e DG |
879 | DBG("Flush buffer for channel %s", channel->channel->name); |
880 | ||
881 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
882 | DBG("Flushing channel stream %d", stream->fd); | |
883 | ret = kernctl_buffer_flush(stream->fd); | |
884 | if (ret < 0) { | |
df0f840b | 885 | PERROR("ioctl"); |
f3ed775e DG |
886 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
887 | stream->fd, ret); | |
888 | } | |
889 | } | |
890 | ||
891 | return 0; | |
892 | } | |
893 | ||
8c0faa1d | 894 | /* |
050349bb | 895 | * Stop tracing session. |
8c0faa1d DG |
896 | */ |
897 | int kernel_stop_session(struct ltt_kernel_session *session) | |
898 | { | |
899 | int ret; | |
900 | ||
0525e9ae DG |
901 | assert(session); |
902 | ||
8c0faa1d DG |
903 | ret = kernctl_stop_session(session->fd); |
904 | if (ret < 0) { | |
905 | goto error; | |
906 | } | |
907 | ||
908 | DBG("Kernel session stopped"); | |
909 | ||
910 | return 0; | |
911 | ||
912 | error: | |
913 | return ret; | |
914 | } | |
915 | ||
916 | /* | |
050349bb DG |
917 | * Open stream of channel, register it to the kernel tracer and add it |
918 | * to the stream list of the channel. | |
8c0faa1d | 919 | * |
1cfb4b98 MD |
920 | * Note: given that the streams may appear in random order wrt CPU |
921 | * number (e.g. cpu hotplug), the index value of the stream number in | |
922 | * the stream name is not necessarily linked to the CPU number. | |
923 | * | |
050349bb | 924 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 925 | */ |
f3ed775e | 926 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 927 | { |
1cfb4b98 | 928 | int ret; |
8c0faa1d DG |
929 | struct ltt_kernel_stream *lks; |
930 | ||
0525e9ae DG |
931 | assert(channel); |
932 | ||
5a47c6a2 | 933 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
934 | lks = trace_kernel_create_stream(channel->channel->name, |
935 | channel->stream_count); | |
8c0faa1d | 936 | if (lks == NULL) { |
799e2c4f MD |
937 | ret = close(ret); |
938 | if (ret) { | |
939 | PERROR("close"); | |
940 | } | |
8c0faa1d DG |
941 | goto error; |
942 | } | |
943 | ||
944 | lks->fd = ret; | |
7b395890 DG |
945 | /* Prevent fd duplication after execlp() */ |
946 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
947 | if (ret < 0) { | |
df0f840b | 948 | PERROR("fcntl session fd"); |
7b395890 DG |
949 | } |
950 | ||
1624d5b7 JD |
951 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
952 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
953 | ||
1cfb4b98 | 954 | /* Add stream to channel stream list */ |
8c0faa1d DG |
955 | cds_list_add(&lks->list, &channel->stream_list.head); |
956 | channel->stream_count++; | |
8c0faa1d | 957 | |
00e2e675 DG |
958 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
959 | lks->state); | |
54012638 | 960 | } |
8c0faa1d DG |
961 | |
962 | return channel->stream_count; | |
963 | ||
964 | error: | |
54012638 | 965 | return -1; |
8c0faa1d DG |
966 | } |
967 | ||
968 | /* | |
050349bb | 969 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 970 | */ |
f3ed775e | 971 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
972 | { |
973 | int ret; | |
974 | ||
0525e9ae DG |
975 | assert(session); |
976 | ||
8c0faa1d DG |
977 | ret = kernctl_create_stream(session->metadata->fd); |
978 | if (ret < 0) { | |
df0f840b | 979 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
980 | goto error; |
981 | } | |
982 | ||
983 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
984 | session->metadata_stream_fd = ret; | |
7b395890 DG |
985 | /* Prevent fd duplication after execlp() */ |
986 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
987 | if (ret < 0) { | |
df0f840b | 988 | PERROR("fcntl session fd"); |
7b395890 | 989 | } |
aaf26714 DG |
990 | |
991 | return 0; | |
992 | ||
993 | error: | |
54012638 | 994 | return -1; |
aaf26714 | 995 | } |
2ef84c95 DG |
996 | |
997 | /* | |
9f19cc17 | 998 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 999 | */ |
9f19cc17 | 1000 | ssize_t kernel_list_events(int tracer_fd, struct lttng_event **events) |
2ef84c95 | 1001 | { |
53efb85a | 1002 | int fd, ret; |
9f19cc17 DG |
1003 | char *event; |
1004 | size_t nbmem, count = 0; | |
2ef84c95 | 1005 | FILE *fp; |
9f19cc17 | 1006 | struct lttng_event *elist; |
2ef84c95 | 1007 | |
0525e9ae DG |
1008 | assert(events); |
1009 | ||
2ef84c95 DG |
1010 | fd = kernctl_tracepoint_list(tracer_fd); |
1011 | if (fd < 0) { | |
df0f840b | 1012 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
1013 | goto error; |
1014 | } | |
1015 | ||
1016 | fp = fdopen(fd, "r"); | |
1017 | if (fp == NULL) { | |
df0f840b | 1018 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 1019 | goto error_fp; |
2ef84c95 DG |
1020 | } |
1021 | ||
1022 | /* | |
1023 | * Init memory size counter | |
1024 | * See kernel-ctl.h for explanation of this value | |
1025 | */ | |
6725fe19 | 1026 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
ba7f0ae5 | 1027 | elist = zmalloc(sizeof(struct lttng_event) * nbmem); |
3b870559 MD |
1028 | if (elist == NULL) { |
1029 | PERROR("alloc list events"); | |
1030 | count = -ENOMEM; | |
1031 | goto end; | |
1032 | } | |
2ef84c95 | 1033 | |
53efb85a | 1034 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 1035 | if (count >= nbmem) { |
3b870559 | 1036 | struct lttng_event *new_elist; |
53efb85a | 1037 | size_t new_nbmem; |
3b870559 | 1038 | |
53efb85a MD |
1039 | new_nbmem = nbmem << 1; |
1040 | DBG("Reallocating event list from %zu to %zu bytes", | |
1041 | nbmem, new_nbmem); | |
1042 | new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event)); | |
3b870559 | 1043 | if (new_elist == NULL) { |
df0f840b | 1044 | PERROR("realloc list events"); |
3b870559 MD |
1045 | free(event); |
1046 | free(elist); | |
61b73b12 MD |
1047 | count = -ENOMEM; |
1048 | goto end; | |
2ef84c95 | 1049 | } |
53efb85a MD |
1050 | /* Zero the new memory */ |
1051 | memset(new_elist + nbmem, 0, | |
1052 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
1053 | nbmem = new_nbmem; | |
3b870559 | 1054 | elist = new_elist; |
2ef84c95 | 1055 | } |
99497cd0 MD |
1056 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
1057 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 1058 | elist[count].enabled = -1; |
9f19cc17 | 1059 | count++; |
3b870559 | 1060 | free(event); |
2ef84c95 DG |
1061 | } |
1062 | ||
9f19cc17 | 1063 | *events = elist; |
ced2f820 | 1064 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 1065 | end: |
799e2c4f MD |
1066 | ret = fclose(fp); /* closes both fp and fd */ |
1067 | if (ret) { | |
1068 | PERROR("fclose"); | |
1069 | } | |
9f19cc17 | 1070 | return count; |
2ef84c95 | 1071 | |
61b73b12 | 1072 | error_fp: |
799e2c4f MD |
1073 | ret = close(fd); |
1074 | if (ret) { | |
1075 | PERROR("close"); | |
1076 | } | |
2ef84c95 DG |
1077 | error: |
1078 | return -1; | |
1079 | } | |
096102bd DG |
1080 | |
1081 | /* | |
1082 | * Get kernel version and validate it. | |
1083 | */ | |
88076e89 JD |
1084 | int kernel_validate_version(int tracer_fd, |
1085 | struct lttng_kernel_tracer_version *version, | |
1086 | struct lttng_kernel_tracer_abi_version *abi_version) | |
096102bd DG |
1087 | { |
1088 | int ret; | |
096102bd | 1089 | |
88076e89 | 1090 | ret = kernctl_tracer_version(tracer_fd, version); |
096102bd | 1091 | if (ret < 0) { |
521dd134 | 1092 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
1093 | goto error; |
1094 | } | |
1095 | ||
1096 | /* Validate version */ | |
88076e89 | 1097 | if (version->major != VERSION_MAJOR) { |
c052142c | 1098 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", |
88076e89 | 1099 | version->major, VERSION_MAJOR); |
096102bd | 1100 | goto error_version; |
096102bd | 1101 | } |
88076e89 | 1102 | ret = kernctl_tracer_abi_version(tracer_fd, abi_version); |
c052142c | 1103 | if (ret < 0) { |
521dd134 | 1104 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
1105 | goto error; |
1106 | } | |
88076e89 | 1107 | if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) { |
521dd134 | 1108 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
88076e89 | 1109 | abi_version->major, abi_version->minor, |
c052142c MD |
1110 | LTTNG_MODULES_ABI_MAJOR_VERSION); |
1111 | goto error; | |
1112 | } | |
1113 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
88076e89 JD |
1114 | version->major, version->minor, |
1115 | abi_version->major, abi_version->minor); | |
096102bd DG |
1116 | return 0; |
1117 | ||
1118 | error_version: | |
096102bd DG |
1119 | ret = -1; |
1120 | ||
1121 | error: | |
521dd134 | 1122 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
1123 | return ret; |
1124 | } | |
335a95b7 MD |
1125 | |
1126 | /* | |
1127 | * Kernel work-arounds called at the start of sessiond main(). | |
1128 | */ | |
1129 | int init_kernel_workarounds(void) | |
1130 | { | |
8936c33a | 1131 | int ret; |
335a95b7 MD |
1132 | FILE *fp; |
1133 | ||
1134 | /* | |
1135 | * boot_id needs to be read once before being used concurrently | |
1136 | * to deal with a Linux kernel race. A fix is proposed for | |
1137 | * upstream, but the work-around is needed for older kernels. | |
1138 | */ | |
1139 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
1140 | if (!fp) { | |
1141 | goto end_boot_id; | |
1142 | } | |
1143 | while (!feof(fp)) { | |
1144 | char buf[37] = ""; | |
1145 | ||
8936c33a DG |
1146 | ret = fread(buf, 1, sizeof(buf), fp); |
1147 | if (ret < 0) { | |
1148 | /* Ignore error, we don't really care */ | |
1149 | } | |
335a95b7 | 1150 | } |
799e2c4f MD |
1151 | ret = fclose(fp); |
1152 | if (ret) { | |
1153 | PERROR("fclose"); | |
1154 | } | |
335a95b7 | 1155 | end_boot_id: |
335a95b7 MD |
1156 | return 0; |
1157 | } | |
2f77fc4b DG |
1158 | |
1159 | /* | |
d070c424 | 1160 | * Teardown of a kernel session, keeping data required by destroy notifiers. |
2f77fc4b DG |
1161 | */ |
1162 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
1163 | { | |
82b69413 JG |
1164 | struct lttng_trace_chunk *trace_chunk; |
1165 | ||
2f77fc4b DG |
1166 | if (ksess == NULL) { |
1167 | DBG3("No kernel session when tearing down session"); | |
1168 | return; | |
1169 | } | |
1170 | ||
1171 | DBG("Tearing down kernel session"); | |
82b69413 | 1172 | trace_chunk = ksess->current_trace_chunk; |
2f77fc4b | 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); | |
82b69413 | 1206 | lttng_trace_chunk_put(trace_chunk); |
2f77fc4b | 1207 | } |
fb5f35b6 | 1208 | |
d070c424 MD |
1209 | /* Teardown of data required by destroy notifiers. */ |
1210 | void kernel_free_session(struct ltt_kernel_session *ksess) | |
1211 | { | |
1212 | if (ksess == NULL) { | |
1213 | return; | |
1214 | } | |
1215 | trace_kernel_free_session(ksess); | |
1216 | } | |
1217 | ||
fb5f35b6 DG |
1218 | /* |
1219 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
1220 | */ | |
1221 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
1222 | { | |
1223 | struct ltt_kernel_session *ksess = NULL; | |
1224 | ||
1225 | assert(kchan); | |
1226 | assert(kchan->channel); | |
1227 | ||
1228 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
1229 | ||
1230 | /* Update channel count of associated session. */ | |
1231 | if (kchan->session) { | |
1232 | /* Keep pointer reference so we can update it after the destroy. */ | |
1233 | ksess = kchan->session; | |
1234 | } | |
1235 | ||
1236 | trace_kernel_destroy_channel(kchan); | |
1237 | ||
1238 | /* | |
1239 | * At this point the kernel channel is not visible anymore. This is safe | |
1240 | * since in order to work on a visible kernel session, the tracing session | |
1241 | * lock (ltt_session.lock) MUST be acquired. | |
1242 | */ | |
1243 | if (ksess) { | |
1244 | ksess->channel_count--; | |
1245 | } | |
1246 | } | |
6dc3064a DG |
1247 | |
1248 | /* | |
1249 | * Take a snapshot for a given kernel session. | |
1250 | * | |
9a654598 | 1251 | * Return LTTNG_OK on success or else return a LTTNG_ERR code. |
6dc3064a | 1252 | */ |
fb9a95c4 JG |
1253 | enum lttng_error_code kernel_snapshot_record( |
1254 | struct ltt_kernel_session *ksess, | |
348a81dc | 1255 | const struct consumer_output *output, int wait, |
d07ceecd | 1256 | uint64_t nb_packets_per_stream) |
6dc3064a | 1257 | { |
2a06df8d | 1258 | int err, ret, saved_metadata_fd; |
9a654598 | 1259 | enum lttng_error_code status = LTTNG_OK; |
6dc3064a DG |
1260 | struct consumer_socket *socket; |
1261 | struct lttng_ht_iter iter; | |
1262 | struct ltt_kernel_metadata *saved_metadata; | |
1263 | ||
1264 | assert(ksess); | |
1265 | assert(ksess->consumer); | |
1266 | assert(output); | |
1267 | ||
1268 | DBG("Kernel snapshot record started"); | |
1269 | ||
1270 | /* Save current metadata since the following calls will change it. */ | |
1271 | saved_metadata = ksess->metadata; | |
1272 | saved_metadata_fd = ksess->metadata_stream_fd; | |
1273 | ||
1274 | rcu_read_lock(); | |
1275 | ||
1276 | ret = kernel_open_metadata(ksess); | |
1277 | if (ret < 0) { | |
9a654598 | 1278 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1279 | goto error; |
1280 | } | |
1281 | ||
1282 | ret = kernel_open_metadata_stream(ksess); | |
1283 | if (ret < 0) { | |
9a654598 | 1284 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1285 | goto error_open_stream; |
1286 | } | |
1287 | ||
1288 | /* Send metadata to consumer and snapshot everything. */ | |
348a81dc | 1289 | cds_lfht_for_each_entry(output->socks->ht, &iter.iter, |
6dc3064a | 1290 | socket, node.node) { |
6dc3064a | 1291 | struct ltt_kernel_channel *chan; |
6dc3064a | 1292 | |
6dc3064a DG |
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); |
6dc3064a | 1297 | if (ret < 0) { |
0ed78e50 | 1298 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1299 | goto error_consumer; |
1300 | } | |
1301 | ||
1302 | /* For each channel, ask the consumer to snapshot it. */ | |
1303 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
9a654598 | 1304 | status = consumer_snapshot_channel(socket, chan->key, output, 0, |
5c786ded JD |
1305 | ksess->uid, ksess->gid, |
1306 | DEFAULT_KERNEL_TRACE_DIR, wait, | |
d2956687 | 1307 | nb_packets_per_stream); |
9a654598 | 1308 | if (status != LTTNG_OK) { |
2a06df8d DG |
1309 | (void) kernel_consumer_destroy_metadata(socket, |
1310 | ksess->metadata); | |
6dc3064a DG |
1311 | goto error_consumer; |
1312 | } | |
1313 | } | |
1314 | ||
1315 | /* Snapshot metadata, */ | |
9a654598 | 1316 | status = consumer_snapshot_channel(socket, ksess->metadata->key, output, |
5c786ded | 1317 | 1, ksess->uid, ksess->gid, |
d2956687 | 1318 | DEFAULT_KERNEL_TRACE_DIR, wait, 0); |
9a654598 | 1319 | if (status != LTTNG_OK) { |
6dc3064a DG |
1320 | goto error_consumer; |
1321 | } | |
07b86b52 JD |
1322 | |
1323 | /* | |
1324 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1325 | * it's not monitored on the consumer side. | |
1326 | */ | |
1327 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1328 | } |
1329 | ||
1330 | error_consumer: | |
1331 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1332 | err = close(ksess->metadata_stream_fd); |
1333 | if (err < 0) { | |
6dc3064a DG |
1334 | PERROR("close snapshot kernel"); |
1335 | } | |
1336 | ||
1337 | error_open_stream: | |
1338 | trace_kernel_destroy_metadata(ksess->metadata); | |
1339 | error: | |
1340 | /* Restore metadata state.*/ | |
1341 | ksess->metadata = saved_metadata; | |
1342 | ksess->metadata_stream_fd = saved_metadata_fd; | |
6dc3064a | 1343 | rcu_read_unlock(); |
9a654598 | 1344 | return status; |
6dc3064a | 1345 | } |
834978fd DG |
1346 | |
1347 | /* | |
1348 | * Get the syscall mask array from the kernel tracer. | |
1349 | * | |
1350 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1351 | * be freed. | |
1352 | */ | |
1353 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1354 | { | |
1355 | assert(syscall_mask); | |
1356 | assert(nr_bits); | |
1357 | ||
1358 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1359 | } | |
6e21424e JR |
1360 | |
1361 | /* | |
1362 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1363 | * version number. | |
1364 | * | |
1365 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1366 | * of errors. | |
1367 | */ | |
1368 | int kernel_supports_ring_buffer_snapshot_sample_positions(int tracer_fd) | |
1369 | { | |
1370 | int ret = 0; // Not supported by default | |
1371 | struct lttng_kernel_tracer_abi_version abi; | |
1372 | ||
1373 | ret = kernctl_tracer_abi_version(tracer_fd, &abi); | |
1374 | if (ret < 0) { | |
1375 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1376 | goto error; | |
1377 | } | |
1378 | ||
1379 | /* | |
1380 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1381 | */ | |
1382 | if (abi.major >= 2 && abi.minor >= 3) { | |
1383 | /* Supported */ | |
1384 | ret = 1; | |
1385 | } else { | |
1386 | /* Not supported */ | |
1387 | ret = 0; | |
1388 | } | |
1389 | error: | |
1390 | return ret; | |
1391 | } | |
5c408ad8 JD |
1392 | |
1393 | /* | |
1394 | * Rotate a kernel session. | |
1395 | * | |
d5a1b7aa | 1396 | * Return LTTNG_OK on success or else an LTTng error code. |
5c408ad8 | 1397 | */ |
d5a1b7aa | 1398 | enum lttng_error_code kernel_rotate_session(struct ltt_session *session) |
5c408ad8 JD |
1399 | { |
1400 | int ret; | |
d5a1b7aa | 1401 | enum lttng_error_code status = LTTNG_OK; |
5c408ad8 JD |
1402 | struct consumer_socket *socket; |
1403 | struct lttng_ht_iter iter; | |
1404 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1405 | ||
1406 | assert(ksess); | |
1407 | assert(ksess->consumer); | |
1408 | ||
1409 | DBG("Rotate kernel session %s started (session %" PRIu64 ")", | |
1410 | session->name, session->id); | |
1411 | ||
1412 | rcu_read_lock(); | |
1413 | ||
1414 | /* | |
1415 | * Note that this loop will end after one iteration given that there is | |
1416 | * only one kernel consumer. | |
1417 | */ | |
1418 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1419 | socket, node.node) { | |
1420 | struct ltt_kernel_channel *chan; | |
1421 | ||
d2956687 | 1422 | /* For each channel, ask the consumer to rotate it. */ |
5c408ad8 | 1423 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { |
92816cc3 JG |
1424 | DBG("Rotate kernel channel %" PRIu64 ", session %s", |
1425 | chan->key, session->name); | |
5c408ad8 JD |
1426 | ret = consumer_rotate_channel(socket, chan->key, |
1427 | ksess->uid, ksess->gid, ksess->consumer, | |
d2956687 | 1428 | /* is_metadata_channel */ false); |
5c408ad8 | 1429 | if (ret < 0) { |
d5a1b7aa | 1430 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1431 | goto error; |
1432 | } | |
1433 | } | |
1434 | ||
1435 | /* | |
1436 | * Rotate the metadata channel. | |
1437 | */ | |
22a1b931 | 1438 | ret = consumer_rotate_channel(socket, ksess->metadata->key, |
5c408ad8 | 1439 | ksess->uid, ksess->gid, ksess->consumer, |
d2956687 | 1440 | /* is_metadata_channel */ true); |
5c408ad8 | 1441 | if (ret < 0) { |
d5a1b7aa | 1442 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1443 | goto error; |
1444 | } | |
1445 | } | |
1446 | ||
5c408ad8 JD |
1447 | error: |
1448 | rcu_read_unlock(); | |
d5a1b7aa | 1449 | return status; |
5c408ad8 | 1450 | } |
d2956687 JG |
1451 | |
1452 | enum lttng_error_code kernel_create_channel_subdirectories( | |
1453 | const struct ltt_kernel_session *ksess) | |
1454 | { | |
1455 | enum lttng_error_code ret = LTTNG_OK; | |
1456 | enum lttng_trace_chunk_status chunk_status; | |
1457 | ||
1458 | rcu_read_lock(); | |
1459 | assert(ksess->current_trace_chunk); | |
1460 | ||
1461 | /* | |
1462 | * Create the index subdirectory which will take care | |
1463 | * of implicitly creating the channel's path. | |
1464 | */ | |
1465 | chunk_status = lttng_trace_chunk_create_subdirectory( | |
1466 | ksess->current_trace_chunk, | |
1467 | DEFAULT_KERNEL_TRACE_DIR "/" DEFAULT_INDEX_DIR); | |
1468 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { | |
1469 | ret = LTTNG_ERR_CREATE_DIR_FAIL; | |
1470 | goto error; | |
1471 | } | |
1472 | error: | |
1473 | rcu_read_unlock(); | |
1474 | return ret; | |
1475 | } |