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> |
7d268848 | 25 | #include <sys/types.h> |
20fe2104 | 26 | |
990570ed | 27 | #include <common/common.h> |
82b69413 | 28 | #include <common/trace-chunk.h> |
db758600 | 29 | #include <common/kernel-ctl/kernel-ctl.h> |
c052142c | 30 | #include <common/kernel-ctl/kernel-ioctl.h> |
42224349 | 31 | #include <common/sessiond-comm/sessiond-comm.h> |
1e307fab | 32 | |
7d268848 MD |
33 | #include "lttng-sessiond.h" |
34 | #include "lttng-syscall.h" | |
2f77fc4b | 35 | #include "consumer.h" |
4771f025 | 36 | #include "kernel.h" |
6dc3064a | 37 | #include "kernel-consumer.h" |
096102bd | 38 | #include "kern-modules.h" |
834978fd | 39 | #include "utils.h" |
5c408ad8 | 40 | #include "rotate.h" |
7d268848 | 41 | #include "modprobe.h" |
20fe2104 | 42 | |
e1f3997a JD |
43 | /* |
44 | * Key used to reference a channel between the sessiond and the consumer. This | |
45 | * is only read and updated with the session_list lock held. | |
46 | */ | |
47 | static uint64_t next_kernel_channel_key; | |
48 | ||
7d268848 MD |
49 | static const char *module_proc_lttng = "/proc/lttng"; |
50 | ||
51 | static int kernel_tracer_fd = -1; | |
52 | ||
410b78a0 FD |
53 | #include <lttng/userspace-probe.h> |
54 | #include <lttng/userspace-probe-internal.h> | |
d65106b1 | 55 | /* |
050349bb | 56 | * Add context on a kernel channel. |
df3c77c8 JG |
57 | * |
58 | * Assumes the ownership of ctx. | |
d65106b1 DG |
59 | */ |
60 | int kernel_add_channel_context(struct ltt_kernel_channel *chan, | |
645328ae | 61 | struct ltt_kernel_context *ctx) |
d65106b1 DG |
62 | { |
63 | int ret; | |
64 | ||
0525e9ae DG |
65 | assert(chan); |
66 | assert(ctx); | |
67 | ||
d65106b1 | 68 | DBG("Adding context to channel %s", chan->channel->name); |
645328ae | 69 | ret = kernctl_add_context(chan->fd, &ctx->ctx); |
d65106b1 | 70 | if (ret < 0) { |
32af2c95 | 71 | switch (-ret) { |
1ae5e83e JD |
72 | case ENOSYS: |
73 | /* Exists but not available for this kernel */ | |
74 | ret = LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE; | |
75 | goto error; | |
76 | case EEXIST: | |
b579acd9 DG |
77 | /* If EEXIST, we just ignore the error */ |
78 | ret = 0; | |
1ae5e83e JD |
79 | goto end; |
80 | default: | |
81 | PERROR("add context ioctl"); | |
82 | ret = LTTNG_ERR_KERN_CONTEXT_FAIL; | |
83 | goto error; | |
b579acd9 | 84 | } |
d65106b1 | 85 | } |
21ed98c1 | 86 | ret = 0; |
d65106b1 | 87 | |
1ae5e83e | 88 | end: |
645328ae | 89 | cds_list_add_tail(&ctx->list, &chan->ctx_list); |
ba985c3a | 90 | ctx->in_list = true; |
df3c77c8 | 91 | ctx = NULL; |
d65106b1 | 92 | error: |
df3c77c8 JG |
93 | if (ctx) { |
94 | trace_kernel_destroy_context(ctx); | |
95 | } | |
d65106b1 DG |
96 | return ret; |
97 | } | |
98 | ||
20fe2104 | 99 | /* |
050349bb DG |
100 | * Create a new kernel session, register it to the kernel tracer and add it to |
101 | * the session daemon session. | |
20fe2104 | 102 | */ |
7d268848 | 103 | int kernel_create_session(struct ltt_session *session) |
20fe2104 DG |
104 | { |
105 | int ret; | |
106 | struct ltt_kernel_session *lks; | |
107 | ||
0525e9ae DG |
108 | assert(session); |
109 | ||
54012638 | 110 | /* Allocate data structure */ |
dec56f6c | 111 | lks = trace_kernel_create_session(); |
20fe2104 | 112 | if (lks == NULL) { |
54012638 | 113 | ret = -1; |
20fe2104 DG |
114 | goto error; |
115 | } | |
116 | ||
54012638 | 117 | /* Kernel tracer session creation */ |
7d268848 | 118 | ret = kernctl_create_session(kernel_tracer_fd); |
20fe2104 | 119 | if (ret < 0) { |
df0f840b | 120 | PERROR("ioctl kernel create session"); |
20fe2104 DG |
121 | goto error; |
122 | } | |
123 | ||
20fe2104 | 124 | lks->fd = ret; |
7b395890 DG |
125 | /* Prevent fd duplication after execlp() */ |
126 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
127 | if (ret < 0) { | |
df0f840b | 128 | PERROR("fcntl session fd"); |
7b395890 DG |
129 | } |
130 | ||
53632229 | 131 | lks->id = session->id; |
3bd1e081 | 132 | lks->consumer_fds_sent = 0; |
8c0faa1d | 133 | session->kernel_session = lks; |
8c0faa1d DG |
134 | |
135 | DBG("Kernel session created (fd: %d)", lks->fd); | |
20fe2104 | 136 | |
8ff4109e JR |
137 | /* |
138 | * This is necessary since the creation time is present in the session | |
139 | * name when it is generated. | |
140 | */ | |
141 | if (session->has_auto_generated_name) { | |
142 | ret = kernctl_session_set_name(lks->fd, DEFAULT_SESSION_NAME); | |
143 | } else { | |
144 | ret = kernctl_session_set_name(lks->fd, session->name); | |
145 | } | |
146 | if (ret) { | |
147 | WARN("Could not set kernel session name for session %" PRIu64 " name: %s", | |
148 | session->id, session->name); | |
149 | } | |
150 | ||
e04b2181 JR |
151 | ret = kernctl_session_set_creation_time(lks->fd, session->creation_time); |
152 | if (ret) { | |
153 | WARN("Could not set kernel session creation time for session %" PRIu64 " name: %s", | |
154 | session->id, session->name); | |
155 | } | |
156 | ||
20fe2104 DG |
157 | return 0; |
158 | ||
159 | error: | |
5f62c685 DG |
160 | if (lks) { |
161 | trace_kernel_destroy_session(lks); | |
d070c424 | 162 | trace_kernel_free_session(lks); |
5f62c685 | 163 | } |
20fe2104 DG |
164 | return ret; |
165 | } | |
166 | ||
167 | /* | |
050349bb DG |
168 | * Create a kernel channel, register it to the kernel tracer and add it to the |
169 | * kernel session. | |
20fe2104 | 170 | */ |
050349bb | 171 | int kernel_create_channel(struct ltt_kernel_session *session, |
fdd9eb17 | 172 | struct lttng_channel *chan) |
20fe2104 DG |
173 | { |
174 | int ret; | |
175 | struct ltt_kernel_channel *lkc; | |
20fe2104 | 176 | |
0525e9ae DG |
177 | assert(session); |
178 | assert(chan); | |
0525e9ae | 179 | |
54012638 | 180 | /* Allocate kernel channel */ |
fdd9eb17 | 181 | lkc = trace_kernel_create_channel(chan); |
54012638 | 182 | if (lkc == NULL) { |
20fe2104 DG |
183 | goto error; |
184 | } | |
185 | ||
ecc48a90 | 186 | DBG3("Kernel create channel %s with attr: %d, %" PRIu64 ", %" PRIu64 ", %u, %u, %d, %d", |
fdd9eb17 | 187 | chan->name, lkc->channel->attr.overwrite, |
173af62f DG |
188 | lkc->channel->attr.subbuf_size, lkc->channel->attr.num_subbuf, |
189 | lkc->channel->attr.switch_timer_interval, lkc->channel->attr.read_timer_interval, | |
ecc48a90 | 190 | lkc->channel->attr.live_timer_interval, lkc->channel->attr.output); |
173af62f | 191 | |
54012638 | 192 | /* Kernel tracer channel creation */ |
f3ed775e | 193 | ret = kernctl_create_channel(session->fd, &lkc->channel->attr); |
20fe2104 | 194 | if (ret < 0) { |
df0f840b | 195 | PERROR("ioctl kernel create channel"); |
20fe2104 DG |
196 | goto error; |
197 | } | |
198 | ||
54012638 | 199 | /* Setup the channel fd */ |
20fe2104 | 200 | lkc->fd = ret; |
7b395890 DG |
201 | /* Prevent fd duplication after execlp() */ |
202 | ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC); | |
203 | if (ret < 0) { | |
df0f840b | 204 | PERROR("fcntl session fd"); |
7b395890 DG |
205 | } |
206 | ||
54012638 | 207 | /* Add channel to session */ |
8c0faa1d DG |
208 | cds_list_add(&lkc->list, &session->channel_list.head); |
209 | session->channel_count++; | |
fb5f35b6 | 210 | lkc->session = session; |
e1f3997a | 211 | lkc->key = ++next_kernel_channel_key; |
20fe2104 | 212 | |
e1f3997a JD |
213 | DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")", |
214 | lkc->channel->name, lkc->fd, lkc->key); | |
20fe2104 DG |
215 | |
216 | return 0; | |
217 | ||
218 | error: | |
5f62c685 DG |
219 | if (lkc) { |
220 | free(lkc->channel); | |
221 | free(lkc); | |
222 | } | |
54012638 | 223 | return -1; |
20fe2104 | 224 | } |
f34daff7 | 225 | |
410b78a0 FD |
226 | /* |
227 | * Compute the offset of the instrumentation byte in the binary based on the | |
228 | * function probe location using the ELF lookup method. | |
229 | * | |
230 | * Returns 0 on success and set the offset out parameter to the offset of the | |
231 | * elf symbol | |
232 | * Returns -1 on error | |
233 | */ | |
234 | static | |
235 | int extract_userspace_probe_offset_function_elf( | |
87597c2c | 236 | const struct lttng_userspace_probe_location *probe_location, |
410b78a0 FD |
237 | struct ltt_kernel_session *session, uint64_t *offset) |
238 | { | |
239 | int fd; | |
240 | int ret = 0; | |
241 | const char *symbol = NULL; | |
87597c2c | 242 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
243 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; |
244 | ||
410b78a0 FD |
245 | assert(lttng_userspace_probe_location_get_type(probe_location) == |
246 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_FUNCTION); | |
247 | ||
248 | lookup = lttng_userspace_probe_location_get_lookup_method( | |
249 | probe_location); | |
250 | if (!lookup) { | |
251 | ret = -1; | |
252 | goto end; | |
253 | } | |
254 | ||
255 | lookup_method_type = | |
256 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
257 | ||
258 | assert(lookup_method_type == | |
259 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF); | |
260 | ||
261 | symbol = lttng_userspace_probe_location_function_get_function_name( | |
262 | probe_location); | |
263 | if (!symbol) { | |
264 | ret = -1; | |
265 | goto end; | |
266 | } | |
267 | ||
268 | fd = lttng_userspace_probe_location_function_get_binary_fd(probe_location); | |
269 | if (fd < 0) { | |
270 | ret = -1; | |
271 | goto end; | |
272 | } | |
273 | ||
274 | ret = run_as_extract_elf_symbol_offset(fd, symbol, session->uid, | |
275 | session->gid, offset); | |
276 | if (ret < 0) { | |
277 | DBG("userspace probe offset calculation failed for " | |
278 | "function %s", symbol); | |
279 | goto end; | |
280 | } | |
281 | ||
282 | DBG("userspace probe elf offset for %s is 0x%jd", symbol, (intmax_t)(*offset)); | |
283 | end: | |
284 | return ret; | |
285 | } | |
286 | ||
287 | /* | |
288 | * Compute the offsets of the instrumentation bytes in the binary based on the | |
289 | * tracepoint probe location using the SDT lookup method. This function | |
290 | * allocates the offsets buffer, the caller must free it. | |
291 | * | |
292 | * Returns 0 on success and set the offset out parameter to the offsets of the | |
293 | * SDT tracepoint. | |
294 | * Returns -1 on error. | |
295 | */ | |
296 | static | |
297 | int extract_userspace_probe_offset_tracepoint_sdt( | |
87597c2c | 298 | const struct lttng_userspace_probe_location *probe_location, |
410b78a0 FD |
299 | struct ltt_kernel_session *session, uint64_t **offsets, |
300 | uint32_t *offsets_count) | |
301 | { | |
302 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; | |
87597c2c | 303 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
304 | const char *probe_name = NULL, *provider_name = NULL; |
305 | int ret = 0; | |
306 | int fd, i; | |
307 | ||
308 | assert(lttng_userspace_probe_location_get_type(probe_location) == | |
309 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_TRACEPOINT); | |
310 | ||
311 | lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); | |
312 | if (!lookup) { | |
313 | ret = -1; | |
314 | goto end; | |
315 | } | |
316 | ||
317 | lookup_method_type = | |
318 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
319 | ||
320 | assert(lookup_method_type == | |
321 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT); | |
322 | ||
323 | ||
324 | probe_name = lttng_userspace_probe_location_tracepoint_get_probe_name( | |
325 | probe_location); | |
326 | if (!probe_name) { | |
327 | ret = -1; | |
328 | goto end; | |
329 | } | |
330 | ||
331 | provider_name = lttng_userspace_probe_location_tracepoint_get_provider_name( | |
332 | probe_location); | |
333 | if (!provider_name) { | |
334 | ret = -1; | |
335 | goto end; | |
336 | } | |
337 | ||
338 | fd = lttng_userspace_probe_location_tracepoint_get_binary_fd(probe_location); | |
339 | if (fd < 0) { | |
340 | ret = -1; | |
341 | goto end; | |
342 | } | |
343 | ||
344 | ret = run_as_extract_sdt_probe_offsets(fd, provider_name, probe_name, | |
345 | session->uid, session->gid, offsets, offsets_count); | |
346 | if (ret < 0) { | |
347 | DBG("userspace probe offset calculation failed for sdt " | |
348 | "probe %s:%s", provider_name, probe_name); | |
349 | goto end; | |
350 | } | |
351 | ||
352 | if (*offsets_count == 0) { | |
353 | DBG("no userspace probe offset found"); | |
354 | goto end; | |
355 | } | |
356 | ||
357 | DBG("%u userspace probe SDT offsets found for %s:%s at:", | |
358 | *offsets_count, provider_name, probe_name); | |
359 | for (i = 0; i < *offsets_count; i++) { | |
360 | DBG("\t0x%jd", (intmax_t)((*offsets)[i])); | |
361 | } | |
362 | end: | |
363 | return ret; | |
364 | } | |
365 | ||
366 | /* | |
367 | * Extract the offsets of the instrumentation point for the different lookup | |
368 | * methods. | |
369 | */ | |
370 | static | |
371 | int userspace_probe_add_callsites(struct lttng_event *ev, | |
372 | struct ltt_kernel_session *session, int fd) | |
373 | { | |
87597c2c | 374 | const struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL; |
410b78a0 | 375 | enum lttng_userspace_probe_location_lookup_method_type type; |
87597c2c | 376 | const struct lttng_userspace_probe_location *location = NULL; |
410b78a0 FD |
377 | int ret; |
378 | ||
379 | assert(ev); | |
380 | assert(ev->type == LTTNG_EVENT_USERSPACE_PROBE); | |
381 | ||
382 | location = lttng_event_get_userspace_probe_location(ev); | |
383 | if (!location) { | |
384 | ret = -1; | |
385 | goto end; | |
386 | } | |
387 | lookup_method = | |
388 | lttng_userspace_probe_location_get_lookup_method(location); | |
389 | if (!lookup_method) { | |
390 | ret = -1; | |
391 | goto end; | |
392 | } | |
393 | ||
394 | type = lttng_userspace_probe_location_lookup_method_get_type(lookup_method); | |
395 | switch (type) { | |
396 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: | |
397 | { | |
398 | struct lttng_kernel_event_callsite callsite; | |
399 | uint64_t offset; | |
400 | ||
401 | ret = extract_userspace_probe_offset_function_elf(location, session, &offset); | |
402 | if (ret) { | |
403 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
404 | goto end; | |
405 | } | |
406 | ||
407 | callsite.u.uprobe.offset = offset; | |
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 | goto end; | |
414 | } | |
415 | break; | |
416 | } | |
417 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: | |
418 | { | |
419 | int i; | |
420 | uint64_t *offsets = NULL; | |
421 | uint32_t offsets_count; | |
422 | struct lttng_kernel_event_callsite callsite; | |
423 | ||
424 | /* | |
425 | * This call allocates the offsets buffer. This buffer must be freed | |
426 | * by the caller | |
427 | */ | |
428 | ret = extract_userspace_probe_offset_tracepoint_sdt(location, session, | |
429 | &offsets, &offsets_count); | |
430 | if (ret) { | |
431 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
432 | goto end; | |
433 | } | |
434 | for (i = 0; i < offsets_count; i++) { | |
435 | callsite.u.uprobe.offset = offsets[i]; | |
436 | ret = kernctl_add_callsite(fd, &callsite); | |
437 | if (ret) { | |
438 | WARN("Adding callsite to userspace probe " | |
439 | "event %s failed.", ev->name); | |
440 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
441 | free(offsets); | |
442 | goto end; | |
443 | } | |
444 | } | |
445 | free(offsets); | |
446 | break; | |
447 | } | |
448 | default: | |
449 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
450 | goto end; | |
451 | } | |
452 | end: | |
453 | return ret; | |
454 | } | |
455 | ||
f34daff7 | 456 | /* |
050349bb DG |
457 | * Create a kernel event, enable it to the kernel tracer and add it to the |
458 | * channel event list of the kernel session. | |
49d21f93 | 459 | * We own filter_expression and filter. |
f34daff7 | 460 | */ |
050349bb | 461 | int kernel_create_event(struct lttng_event *ev, |
00a62084 MD |
462 | struct ltt_kernel_channel *channel, |
463 | char *filter_expression, | |
464 | struct lttng_filter_bytecode *filter) | |
f34daff7 | 465 | { |
71a3bb01 FD |
466 | int err, fd; |
467 | enum lttng_error_code ret; | |
f34daff7 | 468 | struct ltt_kernel_event *event; |
f34daff7 | 469 | |
0525e9ae DG |
470 | assert(ev); |
471 | assert(channel); | |
472 | ||
a969e101 | 473 | /* We pass ownership of filter_expression and filter */ |
71a3bb01 FD |
474 | ret = trace_kernel_create_event(ev, filter_expression, |
475 | filter, &event); | |
476 | if (ret != LTTNG_OK) { | |
f34daff7 DG |
477 | goto error; |
478 | } | |
479 | ||
71a3bb01 FD |
480 | fd = kernctl_create_event(channel->fd, event->event); |
481 | if (fd < 0) { | |
482 | switch (-fd) { | |
bd29c13d | 483 | case EEXIST: |
71a3bb01 | 484 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
bd29c13d DG |
485 | break; |
486 | case ENOSYS: | |
487 | WARN("Event type not implemented"); | |
71a3bb01 | 488 | ret = LTTNG_ERR_KERN_EVENT_ENOSYS; |
bd29c13d | 489 | break; |
8197a339 DG |
490 | case ENOENT: |
491 | WARN("Event %s not found!", ev->name); | |
71a3bb01 | 492 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
8197a339 | 493 | break; |
bd29c13d | 494 | default: |
71a3bb01 | 495 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
d87bfb32 DG |
496 | PERROR("create event ioctl"); |
497 | } | |
e953ef25 | 498 | goto free_event; |
8c0faa1d | 499 | } |
f34daff7 | 500 | |
d0ae4ea8 | 501 | event->type = ev->type; |
71a3bb01 | 502 | event->fd = fd; |
7b395890 | 503 | /* Prevent fd duplication after execlp() */ |
71a3bb01 FD |
504 | err = fcntl(event->fd, F_SETFD, FD_CLOEXEC); |
505 | if (err < 0) { | |
df0f840b | 506 | PERROR("fcntl session fd"); |
7b395890 DG |
507 | } |
508 | ||
00a62084 | 509 | if (filter) { |
71a3bb01 FD |
510 | err = kernctl_filter(event->fd, filter); |
511 | if (err < 0) { | |
512 | switch (-err) { | |
513 | case ENOMEM: | |
514 | ret = LTTNG_ERR_FILTER_NOMEM; | |
515 | break; | |
516 | default: | |
517 | ret = LTTNG_ERR_FILTER_INVAL; | |
518 | break; | |
519 | } | |
00a62084 MD |
520 | goto filter_error; |
521 | } | |
522 | } | |
523 | ||
dcabc190 FD |
524 | if (ev->type == LTTNG_EVENT_USERSPACE_PROBE) { |
525 | ret = userspace_probe_add_callsites(ev, channel->session, event->fd); | |
526 | if (ret) { | |
527 | goto add_callsite_error; | |
528 | } | |
529 | } | |
530 | ||
71a3bb01 FD |
531 | err = kernctl_enable(event->fd); |
532 | if (err < 0) { | |
533 | switch (-err) { | |
00a62084 MD |
534 | case EEXIST: |
535 | ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
536 | break; | |
537 | default: | |
538 | PERROR("enable kernel event"); | |
71a3bb01 | 539 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
00a62084 MD |
540 | break; |
541 | } | |
542 | goto enable_error; | |
543 | } | |
544 | ||
f3ed775e DG |
545 | /* Add event to event list */ |
546 | cds_list_add(&event->list, &channel->events_list.head); | |
cbbbb275 DG |
547 | channel->event_count++; |
548 | ||
e953ef25 DG |
549 | DBG("Event %s created (fd: %d)", ev->name, event->fd); |
550 | ||
551 | return 0; | |
552 | ||
dcabc190 | 553 | add_callsite_error: |
00a62084 MD |
554 | enable_error: |
555 | filter_error: | |
556 | { | |
557 | int closeret; | |
558 | ||
559 | closeret = close(event->fd); | |
560 | if (closeret) { | |
561 | PERROR("close event fd"); | |
562 | } | |
563 | } | |
e953ef25 DG |
564 | free_event: |
565 | free(event); | |
566 | error: | |
d87bfb32 | 567 | return ret; |
e953ef25 DG |
568 | } |
569 | ||
26cc6b4e | 570 | /* |
050349bb | 571 | * Disable a kernel channel. |
26cc6b4e DG |
572 | */ |
573 | int kernel_disable_channel(struct ltt_kernel_channel *chan) | |
574 | { | |
575 | int ret; | |
576 | ||
0525e9ae DG |
577 | assert(chan); |
578 | ||
26cc6b4e DG |
579 | ret = kernctl_disable(chan->fd); |
580 | if (ret < 0) { | |
df0f840b | 581 | PERROR("disable chan ioctl"); |
26cc6b4e DG |
582 | goto error; |
583 | } | |
584 | ||
585 | chan->enabled = 0; | |
e1f3997a JD |
586 | DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")", |
587 | chan->channel->name, chan->fd, chan->key); | |
26cc6b4e DG |
588 | |
589 | return 0; | |
590 | ||
591 | error: | |
592 | return ret; | |
593 | } | |
594 | ||
d36b8583 | 595 | /* |
050349bb | 596 | * Enable a kernel channel. |
d36b8583 DG |
597 | */ |
598 | int kernel_enable_channel(struct ltt_kernel_channel *chan) | |
599 | { | |
600 | int ret; | |
601 | ||
0525e9ae DG |
602 | assert(chan); |
603 | ||
d36b8583 | 604 | ret = kernctl_enable(chan->fd); |
32af2c95 | 605 | if (ret < 0 && ret != -EEXIST) { |
df0f840b | 606 | PERROR("Enable kernel chan"); |
d36b8583 DG |
607 | goto error; |
608 | } | |
609 | ||
610 | chan->enabled = 1; | |
e1f3997a JD |
611 | DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")", |
612 | chan->channel->name, chan->fd, chan->key); | |
d36b8583 DG |
613 | |
614 | return 0; | |
615 | ||
616 | error: | |
617 | return ret; | |
618 | } | |
619 | ||
19e70852 | 620 | /* |
050349bb | 621 | * Enable a kernel event. |
19e70852 DG |
622 | */ |
623 | int kernel_enable_event(struct ltt_kernel_event *event) | |
624 | { | |
625 | int ret; | |
626 | ||
0525e9ae DG |
627 | assert(event); |
628 | ||
19e70852 | 629 | ret = kernctl_enable(event->fd); |
42224349 | 630 | if (ret < 0) { |
32af2c95 | 631 | switch (-ret) { |
42224349 | 632 | case EEXIST: |
f73fabfd | 633 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
634 | break; |
635 | default: | |
636 | PERROR("enable kernel event"); | |
637 | break; | |
638 | } | |
19e70852 DG |
639 | goto error; |
640 | } | |
641 | ||
642 | event->enabled = 1; | |
643 | DBG("Kernel event %s enabled (fd: %d)", event->event->name, event->fd); | |
644 | ||
645 | return 0; | |
646 | ||
647 | error: | |
d36b8583 | 648 | return ret; |
19e70852 DG |
649 | } |
650 | ||
e953ef25 | 651 | /* |
050349bb | 652 | * Disable a kernel event. |
e953ef25 | 653 | */ |
19e70852 | 654 | int kernel_disable_event(struct ltt_kernel_event *event) |
e953ef25 DG |
655 | { |
656 | int ret; | |
19e70852 | 657 | |
0525e9ae DG |
658 | assert(event); |
659 | ||
19e70852 | 660 | ret = kernctl_disable(event->fd); |
42224349 | 661 | if (ret < 0) { |
32af2c95 | 662 | switch (-ret) { |
42224349 | 663 | case EEXIST: |
f73fabfd | 664 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
665 | break; |
666 | default: | |
667 | PERROR("disable kernel event"); | |
668 | break; | |
669 | } | |
19e70852 | 670 | goto error; |
e953ef25 | 671 | } |
f3ed775e | 672 | |
19e70852 DG |
673 | event->enabled = 0; |
674 | DBG("Kernel event %s disabled (fd: %d)", event->event->name, event->fd); | |
675 | ||
f34daff7 DG |
676 | return 0; |
677 | ||
678 | error: | |
d36b8583 | 679 | return ret; |
f34daff7 | 680 | } |
aaf26714 | 681 | |
6e911cad | 682 | |
ccf10263 MD |
683 | int kernel_track_pid(struct ltt_kernel_session *session, int pid) |
684 | { | |
7c493d31 MD |
685 | int ret; |
686 | ||
ccf10263 MD |
687 | DBG("Kernel track PID %d for session id %" PRIu64 ".", |
688 | pid, session->id); | |
7c493d31 MD |
689 | ret = kernctl_track_pid(session->fd, pid); |
690 | if (!ret) { | |
691 | return LTTNG_OK; | |
692 | } | |
32af2c95 | 693 | switch (-ret) { |
7c493d31 MD |
694 | case EINVAL: |
695 | return LTTNG_ERR_INVALID; | |
696 | case ENOMEM: | |
697 | return LTTNG_ERR_NOMEM; | |
698 | case EEXIST: | |
699 | return LTTNG_ERR_PID_TRACKED; | |
700 | default: | |
701 | return LTTNG_ERR_UNK; | |
702 | } | |
ccf10263 MD |
703 | } |
704 | ||
705 | int kernel_untrack_pid(struct ltt_kernel_session *session, int pid) | |
706 | { | |
7c493d31 MD |
707 | int ret; |
708 | ||
ccf10263 MD |
709 | DBG("Kernel untrack PID %d for session id %" PRIu64 ".", |
710 | pid, session->id); | |
7c493d31 MD |
711 | ret = kernctl_untrack_pid(session->fd, pid); |
712 | if (!ret) { | |
713 | return LTTNG_OK; | |
714 | } | |
32af2c95 | 715 | switch (-ret) { |
7c493d31 MD |
716 | case EINVAL: |
717 | return LTTNG_ERR_INVALID; | |
718 | case ENOMEM: | |
719 | return LTTNG_ERR_NOMEM; | |
720 | case ENOENT: | |
721 | return LTTNG_ERR_PID_NOT_TRACKED; | |
722 | default: | |
723 | return LTTNG_ERR_UNK; | |
724 | } | |
ccf10263 MD |
725 | } |
726 | ||
a5dfbb9d MD |
727 | ssize_t kernel_list_tracker_pids(struct ltt_kernel_session *session, |
728 | int **_pids) | |
729 | { | |
730 | int fd, ret; | |
731 | int pid; | |
732 | ssize_t nbmem, count = 0; | |
733 | FILE *fp; | |
734 | int *pids; | |
735 | ||
736 | fd = kernctl_list_tracker_pids(session->fd); | |
737 | if (fd < 0) { | |
738 | PERROR("kernel tracker pids list"); | |
739 | goto error; | |
740 | } | |
741 | ||
742 | fp = fdopen(fd, "r"); | |
743 | if (fp == NULL) { | |
744 | PERROR("kernel tracker pids list fdopen"); | |
745 | goto error_fp; | |
746 | } | |
747 | ||
748 | nbmem = KERNEL_TRACKER_PIDS_INIT_LIST_SIZE; | |
749 | pids = zmalloc(sizeof(*pids) * nbmem); | |
750 | if (pids == NULL) { | |
751 | PERROR("alloc list pids"); | |
752 | count = -ENOMEM; | |
753 | goto end; | |
754 | } | |
755 | ||
756 | while (fscanf(fp, "process { pid = %u; };\n", &pid) == 1) { | |
757 | if (count >= nbmem) { | |
758 | int *new_pids; | |
759 | size_t new_nbmem; | |
760 | ||
761 | new_nbmem = nbmem << 1; | |
762 | DBG("Reallocating pids list from %zu to %zu entries", | |
763 | nbmem, new_nbmem); | |
764 | new_pids = realloc(pids, new_nbmem * sizeof(*new_pids)); | |
765 | if (new_pids == NULL) { | |
766 | PERROR("realloc list events"); | |
767 | free(pids); | |
768 | count = -ENOMEM; | |
769 | goto end; | |
770 | } | |
771 | /* Zero the new memory */ | |
772 | memset(new_pids + nbmem, 0, | |
773 | (new_nbmem - nbmem) * sizeof(*new_pids)); | |
774 | nbmem = new_nbmem; | |
775 | pids = new_pids; | |
776 | } | |
777 | pids[count++] = pid; | |
778 | } | |
779 | ||
780 | *_pids = pids; | |
781 | DBG("Kernel list tracker pids done (%zd pids)", count); | |
782 | end: | |
783 | ret = fclose(fp); /* closes both fp and fd */ | |
784 | if (ret) { | |
785 | PERROR("fclose"); | |
786 | } | |
787 | return count; | |
788 | ||
789 | error_fp: | |
790 | ret = close(fd); | |
791 | if (ret) { | |
792 | PERROR("close"); | |
793 | } | |
794 | error: | |
795 | return -1; | |
796 | } | |
797 | ||
aaf26714 | 798 | /* |
050349bb DG |
799 | * Create kernel metadata, open from the kernel tracer and add it to the |
800 | * kernel session. | |
aaf26714 | 801 | */ |
a4b92340 | 802 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
803 | { |
804 | int ret; | |
74024a21 | 805 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 806 | |
0525e9ae DG |
807 | assert(session); |
808 | ||
54012638 | 809 | /* Allocate kernel metadata */ |
a4b92340 | 810 | lkm = trace_kernel_create_metadata(); |
54012638 | 811 | if (lkm == NULL) { |
aaf26714 DG |
812 | goto error; |
813 | } | |
814 | ||
54012638 | 815 | /* Kernel tracer metadata creation */ |
f3ed775e | 816 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 817 | if (ret < 0) { |
74024a21 | 818 | goto error_open; |
aaf26714 DG |
819 | } |
820 | ||
8c0faa1d | 821 | lkm->fd = ret; |
d40f0359 | 822 | lkm->key = ++next_kernel_channel_key; |
7b395890 DG |
823 | /* Prevent fd duplication after execlp() */ |
824 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
825 | if (ret < 0) { | |
df0f840b | 826 | PERROR("fcntl session fd"); |
7b395890 DG |
827 | } |
828 | ||
aaf26714 | 829 | session->metadata = lkm; |
8c0faa1d | 830 | |
00e2e675 | 831 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
832 | |
833 | return 0; | |
834 | ||
74024a21 DG |
835 | error_open: |
836 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 837 | error: |
54012638 | 838 | return -1; |
8c0faa1d DG |
839 | } |
840 | ||
841 | /* | |
050349bb | 842 | * Start tracing session. |
8c0faa1d DG |
843 | */ |
844 | int kernel_start_session(struct ltt_kernel_session *session) | |
845 | { | |
846 | int ret; | |
847 | ||
0525e9ae DG |
848 | assert(session); |
849 | ||
8c0faa1d DG |
850 | ret = kernctl_start_session(session->fd); |
851 | if (ret < 0) { | |
df0f840b | 852 | PERROR("ioctl start session"); |
8c0faa1d DG |
853 | goto error; |
854 | } | |
855 | ||
856 | DBG("Kernel session started"); | |
857 | ||
858 | return 0; | |
859 | ||
860 | error: | |
861 | return ret; | |
862 | } | |
863 | ||
f3ed775e | 864 | /* |
050349bb | 865 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e | 866 | */ |
7d268848 | 867 | void kernel_wait_quiescent(void) |
f3ed775e DG |
868 | { |
869 | int ret; | |
7d268848 | 870 | int fd = kernel_tracer_fd; |
f3ed775e DG |
871 | |
872 | DBG("Kernel quiescent wait on %d", fd); | |
873 | ||
874 | ret = kernctl_wait_quiescent(fd); | |
875 | if (ret < 0) { | |
df0f840b | 876 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
877 | ERR("Kernel quiescent wait failed"); |
878 | } | |
879 | } | |
880 | ||
881 | /* | |
f3ed775e DG |
882 | * Force flush buffer of metadata. |
883 | */ | |
884 | int kernel_metadata_flush_buffer(int fd) | |
885 | { | |
886 | int ret; | |
887 | ||
169d2cb7 DG |
888 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
889 | ||
f3ed775e DG |
890 | ret = kernctl_buffer_flush(fd); |
891 | if (ret < 0) { | |
00e2e675 | 892 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
893 | } |
894 | ||
895 | return 0; | |
896 | } | |
897 | ||
898 | /* | |
050349bb | 899 | * Force flush buffer for channel. |
f3ed775e DG |
900 | */ |
901 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
902 | { | |
903 | int ret; | |
904 | struct ltt_kernel_stream *stream; | |
905 | ||
0525e9ae DG |
906 | assert(channel); |
907 | ||
f3ed775e DG |
908 | DBG("Flush buffer for channel %s", channel->channel->name); |
909 | ||
910 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
911 | DBG("Flushing channel stream %d", stream->fd); | |
912 | ret = kernctl_buffer_flush(stream->fd); | |
913 | if (ret < 0) { | |
df0f840b | 914 | PERROR("ioctl"); |
f3ed775e DG |
915 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
916 | stream->fd, ret); | |
917 | } | |
918 | } | |
919 | ||
920 | return 0; | |
921 | } | |
922 | ||
8c0faa1d | 923 | /* |
050349bb | 924 | * Stop tracing session. |
8c0faa1d DG |
925 | */ |
926 | int kernel_stop_session(struct ltt_kernel_session *session) | |
927 | { | |
928 | int ret; | |
929 | ||
0525e9ae DG |
930 | assert(session); |
931 | ||
8c0faa1d DG |
932 | ret = kernctl_stop_session(session->fd); |
933 | if (ret < 0) { | |
934 | goto error; | |
935 | } | |
936 | ||
937 | DBG("Kernel session stopped"); | |
938 | ||
939 | return 0; | |
940 | ||
941 | error: | |
942 | return ret; | |
943 | } | |
944 | ||
945 | /* | |
050349bb DG |
946 | * Open stream of channel, register it to the kernel tracer and add it |
947 | * to the stream list of the channel. | |
8c0faa1d | 948 | * |
1cfb4b98 MD |
949 | * Note: given that the streams may appear in random order wrt CPU |
950 | * number (e.g. cpu hotplug), the index value of the stream number in | |
951 | * the stream name is not necessarily linked to the CPU number. | |
952 | * | |
050349bb | 953 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 954 | */ |
f3ed775e | 955 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 956 | { |
1cfb4b98 | 957 | int ret; |
8c0faa1d DG |
958 | struct ltt_kernel_stream *lks; |
959 | ||
0525e9ae DG |
960 | assert(channel); |
961 | ||
5a47c6a2 | 962 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
963 | lks = trace_kernel_create_stream(channel->channel->name, |
964 | channel->stream_count); | |
8c0faa1d | 965 | if (lks == NULL) { |
799e2c4f MD |
966 | ret = close(ret); |
967 | if (ret) { | |
968 | PERROR("close"); | |
969 | } | |
8c0faa1d DG |
970 | goto error; |
971 | } | |
972 | ||
973 | lks->fd = ret; | |
7b395890 DG |
974 | /* Prevent fd duplication after execlp() */ |
975 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
976 | if (ret < 0) { | |
df0f840b | 977 | PERROR("fcntl session fd"); |
7b395890 DG |
978 | } |
979 | ||
1624d5b7 JD |
980 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
981 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
982 | ||
1cfb4b98 | 983 | /* Add stream to channel stream list */ |
8c0faa1d DG |
984 | cds_list_add(&lks->list, &channel->stream_list.head); |
985 | channel->stream_count++; | |
8c0faa1d | 986 | |
00e2e675 DG |
987 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
988 | lks->state); | |
54012638 | 989 | } |
8c0faa1d DG |
990 | |
991 | return channel->stream_count; | |
992 | ||
993 | error: | |
54012638 | 994 | return -1; |
8c0faa1d DG |
995 | } |
996 | ||
997 | /* | |
050349bb | 998 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 999 | */ |
f3ed775e | 1000 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
1001 | { |
1002 | int ret; | |
1003 | ||
0525e9ae DG |
1004 | assert(session); |
1005 | ||
8c0faa1d DG |
1006 | ret = kernctl_create_stream(session->metadata->fd); |
1007 | if (ret < 0) { | |
df0f840b | 1008 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
1009 | goto error; |
1010 | } | |
1011 | ||
1012 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
1013 | session->metadata_stream_fd = ret; | |
7b395890 DG |
1014 | /* Prevent fd duplication after execlp() */ |
1015 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
1016 | if (ret < 0) { | |
df0f840b | 1017 | PERROR("fcntl session fd"); |
7b395890 | 1018 | } |
aaf26714 DG |
1019 | |
1020 | return 0; | |
1021 | ||
1022 | error: | |
54012638 | 1023 | return -1; |
aaf26714 | 1024 | } |
2ef84c95 DG |
1025 | |
1026 | /* | |
9f19cc17 | 1027 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 1028 | */ |
7d268848 | 1029 | ssize_t kernel_list_events(struct lttng_event **events) |
2ef84c95 | 1030 | { |
53efb85a | 1031 | int fd, ret; |
9f19cc17 DG |
1032 | char *event; |
1033 | size_t nbmem, count = 0; | |
2ef84c95 | 1034 | FILE *fp; |
9f19cc17 | 1035 | struct lttng_event *elist; |
2ef84c95 | 1036 | |
0525e9ae DG |
1037 | assert(events); |
1038 | ||
7d268848 | 1039 | fd = kernctl_tracepoint_list(kernel_tracer_fd); |
2ef84c95 | 1040 | if (fd < 0) { |
df0f840b | 1041 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
1042 | goto error; |
1043 | } | |
1044 | ||
1045 | fp = fdopen(fd, "r"); | |
1046 | if (fp == NULL) { | |
df0f840b | 1047 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 1048 | goto error_fp; |
2ef84c95 DG |
1049 | } |
1050 | ||
1051 | /* | |
1052 | * Init memory size counter | |
1053 | * See kernel-ctl.h for explanation of this value | |
1054 | */ | |
6725fe19 | 1055 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
ba7f0ae5 | 1056 | elist = zmalloc(sizeof(struct lttng_event) * nbmem); |
3b870559 MD |
1057 | if (elist == NULL) { |
1058 | PERROR("alloc list events"); | |
1059 | count = -ENOMEM; | |
1060 | goto end; | |
1061 | } | |
2ef84c95 | 1062 | |
53efb85a | 1063 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 1064 | if (count >= nbmem) { |
3b870559 | 1065 | struct lttng_event *new_elist; |
53efb85a | 1066 | size_t new_nbmem; |
3b870559 | 1067 | |
53efb85a MD |
1068 | new_nbmem = nbmem << 1; |
1069 | DBG("Reallocating event list from %zu to %zu bytes", | |
1070 | nbmem, new_nbmem); | |
1071 | new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event)); | |
3b870559 | 1072 | if (new_elist == NULL) { |
df0f840b | 1073 | PERROR("realloc list events"); |
3b870559 MD |
1074 | free(event); |
1075 | free(elist); | |
61b73b12 MD |
1076 | count = -ENOMEM; |
1077 | goto end; | |
2ef84c95 | 1078 | } |
53efb85a MD |
1079 | /* Zero the new memory */ |
1080 | memset(new_elist + nbmem, 0, | |
1081 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
1082 | nbmem = new_nbmem; | |
3b870559 | 1083 | elist = new_elist; |
2ef84c95 | 1084 | } |
99497cd0 MD |
1085 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
1086 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 1087 | elist[count].enabled = -1; |
9f19cc17 | 1088 | count++; |
3b870559 | 1089 | free(event); |
2ef84c95 DG |
1090 | } |
1091 | ||
9f19cc17 | 1092 | *events = elist; |
ced2f820 | 1093 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 1094 | end: |
799e2c4f MD |
1095 | ret = fclose(fp); /* closes both fp and fd */ |
1096 | if (ret) { | |
1097 | PERROR("fclose"); | |
1098 | } | |
9f19cc17 | 1099 | return count; |
2ef84c95 | 1100 | |
61b73b12 | 1101 | error_fp: |
799e2c4f MD |
1102 | ret = close(fd); |
1103 | if (ret) { | |
1104 | PERROR("close"); | |
1105 | } | |
2ef84c95 DG |
1106 | error: |
1107 | return -1; | |
1108 | } | |
096102bd DG |
1109 | |
1110 | /* | |
1111 | * Get kernel version and validate it. | |
1112 | */ | |
7d268848 | 1113 | int kernel_validate_version(struct lttng_kernel_tracer_version *version, |
88076e89 | 1114 | struct lttng_kernel_tracer_abi_version *abi_version) |
096102bd DG |
1115 | { |
1116 | int ret; | |
096102bd | 1117 | |
7d268848 | 1118 | ret = kernctl_tracer_version(kernel_tracer_fd, version); |
096102bd | 1119 | if (ret < 0) { |
521dd134 | 1120 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
1121 | goto error; |
1122 | } | |
1123 | ||
1124 | /* Validate version */ | |
88076e89 | 1125 | if (version->major != VERSION_MAJOR) { |
c052142c | 1126 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", |
88076e89 | 1127 | version->major, VERSION_MAJOR); |
096102bd | 1128 | goto error_version; |
096102bd | 1129 | } |
7d268848 | 1130 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, abi_version); |
c052142c | 1131 | if (ret < 0) { |
521dd134 | 1132 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
1133 | goto error; |
1134 | } | |
88076e89 | 1135 | if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) { |
521dd134 | 1136 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
88076e89 | 1137 | abi_version->major, abi_version->minor, |
c052142c MD |
1138 | LTTNG_MODULES_ABI_MAJOR_VERSION); |
1139 | goto error; | |
1140 | } | |
1141 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
88076e89 JD |
1142 | version->major, version->minor, |
1143 | abi_version->major, abi_version->minor); | |
096102bd DG |
1144 | return 0; |
1145 | ||
1146 | error_version: | |
096102bd DG |
1147 | ret = -1; |
1148 | ||
1149 | error: | |
521dd134 | 1150 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
1151 | return ret; |
1152 | } | |
335a95b7 MD |
1153 | |
1154 | /* | |
1155 | * Kernel work-arounds called at the start of sessiond main(). | |
1156 | */ | |
1157 | int init_kernel_workarounds(void) | |
1158 | { | |
8936c33a | 1159 | int ret; |
335a95b7 MD |
1160 | FILE *fp; |
1161 | ||
1162 | /* | |
1163 | * boot_id needs to be read once before being used concurrently | |
1164 | * to deal with a Linux kernel race. A fix is proposed for | |
1165 | * upstream, but the work-around is needed for older kernels. | |
1166 | */ | |
1167 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
1168 | if (!fp) { | |
1169 | goto end_boot_id; | |
1170 | } | |
1171 | while (!feof(fp)) { | |
1172 | char buf[37] = ""; | |
1173 | ||
8936c33a DG |
1174 | ret = fread(buf, 1, sizeof(buf), fp); |
1175 | if (ret < 0) { | |
1176 | /* Ignore error, we don't really care */ | |
1177 | } | |
335a95b7 | 1178 | } |
799e2c4f MD |
1179 | ret = fclose(fp); |
1180 | if (ret) { | |
1181 | PERROR("fclose"); | |
1182 | } | |
335a95b7 | 1183 | end_boot_id: |
335a95b7 MD |
1184 | return 0; |
1185 | } | |
2f77fc4b DG |
1186 | |
1187 | /* | |
d070c424 | 1188 | * Teardown of a kernel session, keeping data required by destroy notifiers. |
2f77fc4b DG |
1189 | */ |
1190 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
1191 | { | |
82b69413 JG |
1192 | struct lttng_trace_chunk *trace_chunk; |
1193 | ||
2f77fc4b DG |
1194 | if (ksess == NULL) { |
1195 | DBG3("No kernel session when tearing down session"); | |
1196 | return; | |
1197 | } | |
1198 | ||
1199 | DBG("Tearing down kernel session"); | |
82b69413 | 1200 | trace_chunk = ksess->current_trace_chunk; |
2f77fc4b | 1201 | |
07b86b52 | 1202 | /* |
15dc512a DG |
1203 | * Destroy channels on the consumer if at least one FD has been sent and we |
1204 | * are in no output mode because the streams are in *no* monitor mode so we | |
1205 | * have to send a command to clean them up or else they leaked. | |
07b86b52 | 1206 | */ |
15dc512a | 1207 | if (!ksess->output_traces && ksess->consumer_fds_sent) { |
07b86b52 JD |
1208 | int ret; |
1209 | struct consumer_socket *socket; | |
1210 | struct lttng_ht_iter iter; | |
1211 | ||
1212 | /* For each consumer socket. */ | |
d069d577 | 1213 | rcu_read_lock(); |
07b86b52 JD |
1214 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, |
1215 | socket, node.node) { | |
1216 | struct ltt_kernel_channel *chan; | |
1217 | ||
1218 | /* For each channel, ask the consumer to destroy it. */ | |
1219 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1220 | ret = kernel_consumer_destroy_channel(socket, chan); | |
1221 | if (ret < 0) { | |
1222 | /* Consumer is probably dead. Use next socket. */ | |
1223 | continue; | |
1224 | } | |
1225 | } | |
1226 | } | |
d069d577 | 1227 | rcu_read_unlock(); |
07b86b52 JD |
1228 | } |
1229 | ||
2f77fc4b DG |
1230 | /* Close any relayd session */ |
1231 | consumer_output_send_destroy_relayd(ksess->consumer); | |
1232 | ||
1233 | trace_kernel_destroy_session(ksess); | |
82b69413 | 1234 | lttng_trace_chunk_put(trace_chunk); |
2f77fc4b | 1235 | } |
fb5f35b6 | 1236 | |
d070c424 MD |
1237 | /* Teardown of data required by destroy notifiers. */ |
1238 | void kernel_free_session(struct ltt_kernel_session *ksess) | |
1239 | { | |
1240 | if (ksess == NULL) { | |
1241 | return; | |
1242 | } | |
1243 | trace_kernel_free_session(ksess); | |
1244 | } | |
1245 | ||
fb5f35b6 DG |
1246 | /* |
1247 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
1248 | */ | |
1249 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
1250 | { | |
1251 | struct ltt_kernel_session *ksess = NULL; | |
1252 | ||
1253 | assert(kchan); | |
1254 | assert(kchan->channel); | |
1255 | ||
1256 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
1257 | ||
1258 | /* Update channel count of associated session. */ | |
1259 | if (kchan->session) { | |
1260 | /* Keep pointer reference so we can update it after the destroy. */ | |
1261 | ksess = kchan->session; | |
1262 | } | |
1263 | ||
1264 | trace_kernel_destroy_channel(kchan); | |
1265 | ||
1266 | /* | |
1267 | * At this point the kernel channel is not visible anymore. This is safe | |
1268 | * since in order to work on a visible kernel session, the tracing session | |
1269 | * lock (ltt_session.lock) MUST be acquired. | |
1270 | */ | |
1271 | if (ksess) { | |
1272 | ksess->channel_count--; | |
1273 | } | |
1274 | } | |
6dc3064a DG |
1275 | |
1276 | /* | |
1277 | * Take a snapshot for a given kernel session. | |
1278 | * | |
9a654598 | 1279 | * Return LTTNG_OK on success or else return a LTTNG_ERR code. |
6dc3064a | 1280 | */ |
fb9a95c4 JG |
1281 | enum lttng_error_code kernel_snapshot_record( |
1282 | struct ltt_kernel_session *ksess, | |
348a81dc | 1283 | const struct consumer_output *output, int wait, |
d07ceecd | 1284 | uint64_t nb_packets_per_stream) |
6dc3064a | 1285 | { |
2a06df8d | 1286 | int err, ret, saved_metadata_fd; |
9a654598 | 1287 | enum lttng_error_code status = LTTNG_OK; |
6dc3064a DG |
1288 | struct consumer_socket *socket; |
1289 | struct lttng_ht_iter iter; | |
1290 | struct ltt_kernel_metadata *saved_metadata; | |
3b967712 | 1291 | char *trace_path = NULL; |
6dc3064a DG |
1292 | |
1293 | assert(ksess); | |
1294 | assert(ksess->consumer); | |
1295 | assert(output); | |
1296 | ||
1297 | DBG("Kernel snapshot record started"); | |
1298 | ||
1299 | /* Save current metadata since the following calls will change it. */ | |
1300 | saved_metadata = ksess->metadata; | |
1301 | saved_metadata_fd = ksess->metadata_stream_fd; | |
1302 | ||
1303 | rcu_read_lock(); | |
1304 | ||
1305 | ret = kernel_open_metadata(ksess); | |
1306 | if (ret < 0) { | |
9a654598 | 1307 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1308 | goto error; |
1309 | } | |
1310 | ||
1311 | ret = kernel_open_metadata_stream(ksess); | |
1312 | if (ret < 0) { | |
9a654598 | 1313 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1314 | goto error_open_stream; |
1315 | } | |
1316 | ||
3b967712 MD |
1317 | trace_path = setup_channel_trace_path(ksess->consumer, |
1318 | DEFAULT_KERNEL_TRACE_DIR); | |
1319 | if (!trace_path) { | |
1320 | status = LTTNG_ERR_INVALID; | |
1321 | goto error; | |
1322 | } | |
6dc3064a | 1323 | /* Send metadata to consumer and snapshot everything. */ |
348a81dc | 1324 | cds_lfht_for_each_entry(output->socks->ht, &iter.iter, |
6dc3064a | 1325 | socket, node.node) { |
6dc3064a | 1326 | struct ltt_kernel_channel *chan; |
6dc3064a | 1327 | |
6dc3064a DG |
1328 | pthread_mutex_lock(socket->lock); |
1329 | /* This stream must not be monitored by the consumer. */ | |
07b86b52 | 1330 | ret = kernel_consumer_add_metadata(socket, ksess, 0); |
6dc3064a | 1331 | pthread_mutex_unlock(socket->lock); |
6dc3064a | 1332 | if (ret < 0) { |
0ed78e50 | 1333 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1334 | goto error_consumer; |
1335 | } | |
1336 | ||
1337 | /* For each channel, ask the consumer to snapshot it. */ | |
1338 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
9a654598 | 1339 | status = consumer_snapshot_channel(socket, chan->key, output, 0, |
5c786ded | 1340 | ksess->uid, ksess->gid, |
3b967712 | 1341 | trace_path, wait, |
d2956687 | 1342 | nb_packets_per_stream); |
9a654598 | 1343 | if (status != LTTNG_OK) { |
2a06df8d DG |
1344 | (void) kernel_consumer_destroy_metadata(socket, |
1345 | ksess->metadata); | |
6dc3064a DG |
1346 | goto error_consumer; |
1347 | } | |
1348 | } | |
1349 | ||
1350 | /* Snapshot metadata, */ | |
9a654598 | 1351 | status = consumer_snapshot_channel(socket, ksess->metadata->key, output, |
3b967712 | 1352 | 1, ksess->uid, ksess->gid, trace_path, wait, 0); |
9a654598 | 1353 | if (status != LTTNG_OK) { |
6dc3064a DG |
1354 | goto error_consumer; |
1355 | } | |
07b86b52 JD |
1356 | |
1357 | /* | |
1358 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1359 | * it's not monitored on the consumer side. | |
1360 | */ | |
1361 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1362 | } |
1363 | ||
1364 | error_consumer: | |
1365 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1366 | err = close(ksess->metadata_stream_fd); |
1367 | if (err < 0) { | |
6dc3064a DG |
1368 | PERROR("close snapshot kernel"); |
1369 | } | |
1370 | ||
1371 | error_open_stream: | |
1372 | trace_kernel_destroy_metadata(ksess->metadata); | |
1373 | error: | |
1374 | /* Restore metadata state.*/ | |
1375 | ksess->metadata = saved_metadata; | |
1376 | ksess->metadata_stream_fd = saved_metadata_fd; | |
6dc3064a | 1377 | rcu_read_unlock(); |
3b967712 | 1378 | free(trace_path); |
9a654598 | 1379 | return status; |
6dc3064a | 1380 | } |
834978fd DG |
1381 | |
1382 | /* | |
1383 | * Get the syscall mask array from the kernel tracer. | |
1384 | * | |
1385 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1386 | * be freed. | |
1387 | */ | |
1388 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1389 | { | |
1390 | assert(syscall_mask); | |
1391 | assert(nr_bits); | |
1392 | ||
1393 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1394 | } | |
6e21424e JR |
1395 | |
1396 | /* | |
1397 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1398 | * version number. | |
1399 | * | |
1400 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1401 | * of errors. | |
1402 | */ | |
7d268848 | 1403 | int kernel_supports_ring_buffer_snapshot_sample_positions(void) |
6e21424e JR |
1404 | { |
1405 | int ret = 0; // Not supported by default | |
1406 | struct lttng_kernel_tracer_abi_version abi; | |
1407 | ||
7d268848 | 1408 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, &abi); |
6e21424e JR |
1409 | if (ret < 0) { |
1410 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1411 | goto error; | |
1412 | } | |
1413 | ||
1414 | /* | |
1415 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1416 | */ | |
1417 | if (abi.major >= 2 && abi.minor >= 3) { | |
1418 | /* Supported */ | |
1419 | ret = 1; | |
1420 | } else { | |
1421 | /* Not supported */ | |
1422 | ret = 0; | |
1423 | } | |
1424 | error: | |
1425 | return ret; | |
1426 | } | |
5c408ad8 JD |
1427 | |
1428 | /* | |
1429 | * Rotate a kernel session. | |
1430 | * | |
d5a1b7aa | 1431 | * Return LTTNG_OK on success or else an LTTng error code. |
5c408ad8 | 1432 | */ |
d5a1b7aa | 1433 | enum lttng_error_code kernel_rotate_session(struct ltt_session *session) |
5c408ad8 JD |
1434 | { |
1435 | int ret; | |
d5a1b7aa | 1436 | enum lttng_error_code status = LTTNG_OK; |
5c408ad8 JD |
1437 | struct consumer_socket *socket; |
1438 | struct lttng_ht_iter iter; | |
1439 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1440 | ||
1441 | assert(ksess); | |
1442 | assert(ksess->consumer); | |
1443 | ||
1444 | DBG("Rotate kernel session %s started (session %" PRIu64 ")", | |
1445 | session->name, session->id); | |
1446 | ||
1447 | rcu_read_lock(); | |
1448 | ||
1449 | /* | |
1450 | * Note that this loop will end after one iteration given that there is | |
1451 | * only one kernel consumer. | |
1452 | */ | |
1453 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1454 | socket, node.node) { | |
1455 | struct ltt_kernel_channel *chan; | |
1456 | ||
d2956687 | 1457 | /* For each channel, ask the consumer to rotate it. */ |
5c408ad8 | 1458 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { |
92816cc3 JG |
1459 | DBG("Rotate kernel channel %" PRIu64 ", session %s", |
1460 | chan->key, session->name); | |
5c408ad8 JD |
1461 | ret = consumer_rotate_channel(socket, chan->key, |
1462 | ksess->uid, ksess->gid, ksess->consumer, | |
d2956687 | 1463 | /* is_metadata_channel */ false); |
5c408ad8 | 1464 | if (ret < 0) { |
d5a1b7aa | 1465 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1466 | goto error; |
1467 | } | |
1468 | } | |
1469 | ||
1470 | /* | |
1471 | * Rotate the metadata channel. | |
1472 | */ | |
22a1b931 | 1473 | ret = consumer_rotate_channel(socket, ksess->metadata->key, |
5c408ad8 | 1474 | ksess->uid, ksess->gid, ksess->consumer, |
d2956687 | 1475 | /* is_metadata_channel */ true); |
5c408ad8 | 1476 | if (ret < 0) { |
d5a1b7aa | 1477 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1478 | goto error; |
1479 | } | |
1480 | } | |
1481 | ||
5c408ad8 JD |
1482 | error: |
1483 | rcu_read_unlock(); | |
d5a1b7aa | 1484 | return status; |
5c408ad8 | 1485 | } |
d2956687 JG |
1486 | |
1487 | enum lttng_error_code kernel_create_channel_subdirectories( | |
1488 | const struct ltt_kernel_session *ksess) | |
1489 | { | |
1490 | enum lttng_error_code ret = LTTNG_OK; | |
1491 | enum lttng_trace_chunk_status chunk_status; | |
1492 | ||
1493 | rcu_read_lock(); | |
1494 | assert(ksess->current_trace_chunk); | |
1495 | ||
1496 | /* | |
1497 | * Create the index subdirectory which will take care | |
1498 | * of implicitly creating the channel's path. | |
1499 | */ | |
1500 | chunk_status = lttng_trace_chunk_create_subdirectory( | |
1501 | ksess->current_trace_chunk, | |
1502 | DEFAULT_KERNEL_TRACE_DIR "/" DEFAULT_INDEX_DIR); | |
1503 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { | |
1504 | ret = LTTNG_ERR_CREATE_DIR_FAIL; | |
1505 | goto error; | |
1506 | } | |
1507 | error: | |
1508 | rcu_read_unlock(); | |
1509 | return ret; | |
1510 | } | |
7d268848 MD |
1511 | |
1512 | /* | |
1513 | * Setup necessary data for kernel tracer action. | |
1514 | */ | |
1515 | LTTNG_HIDDEN | |
1516 | int init_kernel_tracer(void) | |
1517 | { | |
1518 | int ret; | |
1519 | bool is_root = !getuid(); | |
1520 | ||
1521 | /* Modprobe lttng kernel modules */ | |
1522 | ret = modprobe_lttng_control(); | |
1523 | if (ret < 0) { | |
1524 | goto error; | |
1525 | } | |
1526 | ||
1527 | /* Open debugfs lttng */ | |
1528 | kernel_tracer_fd = open(module_proc_lttng, O_RDWR); | |
1529 | if (kernel_tracer_fd < 0) { | |
1530 | DBG("Failed to open %s", module_proc_lttng); | |
1531 | goto error_open; | |
1532 | } | |
1533 | ||
1534 | /* Validate kernel version */ | |
1535 | ret = kernel_validate_version(&kernel_tracer_version, | |
1536 | &kernel_tracer_abi_version); | |
1537 | if (ret < 0) { | |
1538 | goto error_version; | |
1539 | } | |
1540 | ||
1541 | ret = modprobe_lttng_data(); | |
1542 | if (ret < 0) { | |
1543 | goto error_modules; | |
1544 | } | |
1545 | ||
1546 | ret = kernel_supports_ring_buffer_snapshot_sample_positions(); | |
1547 | if (ret < 0) { | |
1548 | goto error_modules; | |
1549 | } | |
1550 | ||
1551 | if (ret < 1) { | |
1552 | WARN("Kernel tracer does not support buffer monitoring. " | |
1553 | "The monitoring timer of channels in the kernel domain " | |
1554 | "will be set to 0 (disabled)."); | |
1555 | } | |
1556 | ||
1557 | DBG("Kernel tracer fd %d", kernel_tracer_fd); | |
1558 | ||
1559 | ret = syscall_init_table(kernel_tracer_fd); | |
1560 | if (ret < 0) { | |
1561 | ERR("Unable to populate syscall table. Syscall tracing won't " | |
1562 | "work for this session daemon."); | |
1563 | } | |
1564 | return 0; | |
1565 | ||
1566 | error_version: | |
1567 | modprobe_remove_lttng_control(); | |
1568 | ret = close(kernel_tracer_fd); | |
1569 | if (ret) { | |
1570 | PERROR("close"); | |
1571 | } | |
1572 | kernel_tracer_fd = -1; | |
1573 | return LTTNG_ERR_KERN_VERSION; | |
1574 | ||
1575 | error_modules: | |
1576 | ret = close(kernel_tracer_fd); | |
1577 | if (ret) { | |
1578 | PERROR("close"); | |
1579 | } | |
1580 | ||
1581 | error_open: | |
1582 | modprobe_remove_lttng_control(); | |
1583 | ||
1584 | error: | |
1585 | WARN("No kernel tracer available"); | |
1586 | kernel_tracer_fd = -1; | |
1587 | if (!is_root) { | |
1588 | return LTTNG_ERR_NEED_ROOT_SESSIOND; | |
1589 | } else { | |
1590 | return LTTNG_ERR_KERN_NA; | |
1591 | } | |
1592 | } | |
1593 | ||
1594 | LTTNG_HIDDEN | |
1595 | void cleanup_kernel_tracer(void) | |
1596 | { | |
1597 | int ret; | |
1598 | ||
1599 | DBG2("Closing kernel fd"); | |
1600 | if (kernel_tracer_fd >= 0) { | |
1601 | ret = close(kernel_tracer_fd); | |
1602 | if (ret) { | |
1603 | PERROR("close"); | |
1604 | } | |
1605 | kernel_tracer_fd = -1; | |
1606 | } | |
1607 | DBG("Unloading kernel modules"); | |
1608 | modprobe_remove_lttng_all(); | |
1609 | free(syscall_table); | |
1610 | } | |
1611 | ||
1612 | LTTNG_HIDDEN | |
1613 | bool kernel_tracer_is_initialized(void) | |
1614 | { | |
1615 | return kernel_tracer_fd >= 0; | |
1616 | } |