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 | ||
20fe2104 DG |
151 | return 0; |
152 | ||
153 | error: | |
5f62c685 DG |
154 | if (lks) { |
155 | trace_kernel_destroy_session(lks); | |
d070c424 | 156 | trace_kernel_free_session(lks); |
5f62c685 | 157 | } |
20fe2104 DG |
158 | return ret; |
159 | } | |
160 | ||
161 | /* | |
050349bb DG |
162 | * Create a kernel channel, register it to the kernel tracer and add it to the |
163 | * kernel session. | |
20fe2104 | 164 | */ |
050349bb | 165 | int kernel_create_channel(struct ltt_kernel_session *session, |
fdd9eb17 | 166 | struct lttng_channel *chan) |
20fe2104 DG |
167 | { |
168 | int ret; | |
169 | struct ltt_kernel_channel *lkc; | |
20fe2104 | 170 | |
0525e9ae DG |
171 | assert(session); |
172 | assert(chan); | |
0525e9ae | 173 | |
54012638 | 174 | /* Allocate kernel channel */ |
fdd9eb17 | 175 | lkc = trace_kernel_create_channel(chan); |
54012638 | 176 | if (lkc == NULL) { |
20fe2104 DG |
177 | goto error; |
178 | } | |
179 | ||
ecc48a90 | 180 | DBG3("Kernel create channel %s with attr: %d, %" PRIu64 ", %" PRIu64 ", %u, %u, %d, %d", |
fdd9eb17 | 181 | chan->name, lkc->channel->attr.overwrite, |
173af62f DG |
182 | lkc->channel->attr.subbuf_size, lkc->channel->attr.num_subbuf, |
183 | lkc->channel->attr.switch_timer_interval, lkc->channel->attr.read_timer_interval, | |
ecc48a90 | 184 | lkc->channel->attr.live_timer_interval, lkc->channel->attr.output); |
173af62f | 185 | |
54012638 | 186 | /* Kernel tracer channel creation */ |
f3ed775e | 187 | ret = kernctl_create_channel(session->fd, &lkc->channel->attr); |
20fe2104 | 188 | if (ret < 0) { |
df0f840b | 189 | PERROR("ioctl kernel create channel"); |
20fe2104 DG |
190 | goto error; |
191 | } | |
192 | ||
54012638 | 193 | /* Setup the channel fd */ |
20fe2104 | 194 | lkc->fd = ret; |
7b395890 DG |
195 | /* Prevent fd duplication after execlp() */ |
196 | ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC); | |
197 | if (ret < 0) { | |
df0f840b | 198 | PERROR("fcntl session fd"); |
7b395890 DG |
199 | } |
200 | ||
54012638 | 201 | /* Add channel to session */ |
8c0faa1d DG |
202 | cds_list_add(&lkc->list, &session->channel_list.head); |
203 | session->channel_count++; | |
fb5f35b6 | 204 | lkc->session = session; |
e1f3997a | 205 | lkc->key = ++next_kernel_channel_key; |
20fe2104 | 206 | |
e1f3997a JD |
207 | DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")", |
208 | lkc->channel->name, lkc->fd, lkc->key); | |
20fe2104 DG |
209 | |
210 | return 0; | |
211 | ||
212 | error: | |
5f62c685 DG |
213 | if (lkc) { |
214 | free(lkc->channel); | |
215 | free(lkc); | |
216 | } | |
54012638 | 217 | return -1; |
20fe2104 | 218 | } |
f34daff7 | 219 | |
410b78a0 FD |
220 | /* |
221 | * Compute the offset of the instrumentation byte in the binary based on the | |
222 | * function probe location using the ELF lookup method. | |
223 | * | |
224 | * Returns 0 on success and set the offset out parameter to the offset of the | |
225 | * elf symbol | |
226 | * Returns -1 on error | |
227 | */ | |
228 | static | |
229 | int extract_userspace_probe_offset_function_elf( | |
87597c2c | 230 | const struct lttng_userspace_probe_location *probe_location, |
410b78a0 FD |
231 | struct ltt_kernel_session *session, uint64_t *offset) |
232 | { | |
233 | int fd; | |
234 | int ret = 0; | |
235 | const char *symbol = NULL; | |
87597c2c | 236 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
237 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; |
238 | ||
410b78a0 FD |
239 | assert(lttng_userspace_probe_location_get_type(probe_location) == |
240 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_FUNCTION); | |
241 | ||
242 | lookup = lttng_userspace_probe_location_get_lookup_method( | |
243 | probe_location); | |
244 | if (!lookup) { | |
245 | ret = -1; | |
246 | goto end; | |
247 | } | |
248 | ||
249 | lookup_method_type = | |
250 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
251 | ||
252 | assert(lookup_method_type == | |
253 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF); | |
254 | ||
255 | symbol = lttng_userspace_probe_location_function_get_function_name( | |
256 | probe_location); | |
257 | if (!symbol) { | |
258 | ret = -1; | |
259 | goto end; | |
260 | } | |
261 | ||
262 | fd = lttng_userspace_probe_location_function_get_binary_fd(probe_location); | |
263 | if (fd < 0) { | |
264 | ret = -1; | |
265 | goto end; | |
266 | } | |
267 | ||
268 | ret = run_as_extract_elf_symbol_offset(fd, symbol, session->uid, | |
269 | session->gid, offset); | |
270 | if (ret < 0) { | |
271 | DBG("userspace probe offset calculation failed for " | |
272 | "function %s", symbol); | |
273 | goto end; | |
274 | } | |
275 | ||
276 | DBG("userspace probe elf offset for %s is 0x%jd", symbol, (intmax_t)(*offset)); | |
277 | end: | |
278 | return ret; | |
279 | } | |
280 | ||
281 | /* | |
282 | * Compute the offsets of the instrumentation bytes in the binary based on the | |
283 | * tracepoint probe location using the SDT lookup method. This function | |
284 | * allocates the offsets buffer, the caller must free it. | |
285 | * | |
286 | * Returns 0 on success and set the offset out parameter to the offsets of the | |
287 | * SDT tracepoint. | |
288 | * Returns -1 on error. | |
289 | */ | |
290 | static | |
291 | int extract_userspace_probe_offset_tracepoint_sdt( | |
87597c2c | 292 | const struct lttng_userspace_probe_location *probe_location, |
410b78a0 FD |
293 | struct ltt_kernel_session *session, uint64_t **offsets, |
294 | uint32_t *offsets_count) | |
295 | { | |
296 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; | |
87597c2c | 297 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
298 | const char *probe_name = NULL, *provider_name = NULL; |
299 | int ret = 0; | |
300 | int fd, i; | |
301 | ||
302 | assert(lttng_userspace_probe_location_get_type(probe_location) == | |
303 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_TRACEPOINT); | |
304 | ||
305 | lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); | |
306 | if (!lookup) { | |
307 | ret = -1; | |
308 | goto end; | |
309 | } | |
310 | ||
311 | lookup_method_type = | |
312 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
313 | ||
314 | assert(lookup_method_type == | |
315 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT); | |
316 | ||
317 | ||
318 | probe_name = lttng_userspace_probe_location_tracepoint_get_probe_name( | |
319 | probe_location); | |
320 | if (!probe_name) { | |
321 | ret = -1; | |
322 | goto end; | |
323 | } | |
324 | ||
325 | provider_name = lttng_userspace_probe_location_tracepoint_get_provider_name( | |
326 | probe_location); | |
327 | if (!provider_name) { | |
328 | ret = -1; | |
329 | goto end; | |
330 | } | |
331 | ||
332 | fd = lttng_userspace_probe_location_tracepoint_get_binary_fd(probe_location); | |
333 | if (fd < 0) { | |
334 | ret = -1; | |
335 | goto end; | |
336 | } | |
337 | ||
338 | ret = run_as_extract_sdt_probe_offsets(fd, provider_name, probe_name, | |
339 | session->uid, session->gid, offsets, offsets_count); | |
340 | if (ret < 0) { | |
341 | DBG("userspace probe offset calculation failed for sdt " | |
342 | "probe %s:%s", provider_name, probe_name); | |
343 | goto end; | |
344 | } | |
345 | ||
346 | if (*offsets_count == 0) { | |
347 | DBG("no userspace probe offset found"); | |
348 | goto end; | |
349 | } | |
350 | ||
351 | DBG("%u userspace probe SDT offsets found for %s:%s at:", | |
352 | *offsets_count, provider_name, probe_name); | |
353 | for (i = 0; i < *offsets_count; i++) { | |
354 | DBG("\t0x%jd", (intmax_t)((*offsets)[i])); | |
355 | } | |
356 | end: | |
357 | return ret; | |
358 | } | |
359 | ||
360 | /* | |
361 | * Extract the offsets of the instrumentation point for the different lookup | |
362 | * methods. | |
363 | */ | |
364 | static | |
365 | int userspace_probe_add_callsites(struct lttng_event *ev, | |
366 | struct ltt_kernel_session *session, int fd) | |
367 | { | |
87597c2c | 368 | const struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL; |
410b78a0 | 369 | enum lttng_userspace_probe_location_lookup_method_type type; |
87597c2c | 370 | const struct lttng_userspace_probe_location *location = NULL; |
410b78a0 FD |
371 | int ret; |
372 | ||
373 | assert(ev); | |
374 | assert(ev->type == LTTNG_EVENT_USERSPACE_PROBE); | |
375 | ||
376 | location = lttng_event_get_userspace_probe_location(ev); | |
377 | if (!location) { | |
378 | ret = -1; | |
379 | goto end; | |
380 | } | |
381 | lookup_method = | |
382 | lttng_userspace_probe_location_get_lookup_method(location); | |
383 | if (!lookup_method) { | |
384 | ret = -1; | |
385 | goto end; | |
386 | } | |
387 | ||
388 | type = lttng_userspace_probe_location_lookup_method_get_type(lookup_method); | |
389 | switch (type) { | |
390 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: | |
391 | { | |
392 | struct lttng_kernel_event_callsite callsite; | |
393 | uint64_t offset; | |
394 | ||
395 | ret = extract_userspace_probe_offset_function_elf(location, session, &offset); | |
396 | if (ret) { | |
397 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
398 | goto end; | |
399 | } | |
400 | ||
401 | callsite.u.uprobe.offset = offset; | |
402 | ret = kernctl_add_callsite(fd, &callsite); | |
403 | if (ret) { | |
404 | WARN("Adding callsite to userspace probe " | |
405 | "event %s failed.", ev->name); | |
406 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
407 | goto end; | |
408 | } | |
409 | break; | |
410 | } | |
411 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: | |
412 | { | |
413 | int i; | |
414 | uint64_t *offsets = NULL; | |
415 | uint32_t offsets_count; | |
416 | struct lttng_kernel_event_callsite callsite; | |
417 | ||
418 | /* | |
419 | * This call allocates the offsets buffer. This buffer must be freed | |
420 | * by the caller | |
421 | */ | |
422 | ret = extract_userspace_probe_offset_tracepoint_sdt(location, session, | |
423 | &offsets, &offsets_count); | |
424 | if (ret) { | |
425 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
426 | goto end; | |
427 | } | |
428 | for (i = 0; i < offsets_count; i++) { | |
429 | callsite.u.uprobe.offset = offsets[i]; | |
430 | ret = kernctl_add_callsite(fd, &callsite); | |
431 | if (ret) { | |
432 | WARN("Adding callsite to userspace probe " | |
433 | "event %s failed.", ev->name); | |
434 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
435 | free(offsets); | |
436 | goto end; | |
437 | } | |
438 | } | |
439 | free(offsets); | |
440 | break; | |
441 | } | |
442 | default: | |
443 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
444 | goto end; | |
445 | } | |
446 | end: | |
447 | return ret; | |
448 | } | |
449 | ||
f34daff7 | 450 | /* |
050349bb DG |
451 | * Create a kernel event, enable it to the kernel tracer and add it to the |
452 | * channel event list of the kernel session. | |
49d21f93 | 453 | * We own filter_expression and filter. |
f34daff7 | 454 | */ |
050349bb | 455 | int kernel_create_event(struct lttng_event *ev, |
00a62084 MD |
456 | struct ltt_kernel_channel *channel, |
457 | char *filter_expression, | |
458 | struct lttng_filter_bytecode *filter) | |
f34daff7 | 459 | { |
71a3bb01 FD |
460 | int err, fd; |
461 | enum lttng_error_code ret; | |
f34daff7 | 462 | struct ltt_kernel_event *event; |
f34daff7 | 463 | |
0525e9ae DG |
464 | assert(ev); |
465 | assert(channel); | |
466 | ||
a969e101 | 467 | /* We pass ownership of filter_expression and filter */ |
71a3bb01 FD |
468 | ret = trace_kernel_create_event(ev, filter_expression, |
469 | filter, &event); | |
470 | if (ret != LTTNG_OK) { | |
f34daff7 DG |
471 | goto error; |
472 | } | |
473 | ||
71a3bb01 FD |
474 | fd = kernctl_create_event(channel->fd, event->event); |
475 | if (fd < 0) { | |
476 | switch (-fd) { | |
bd29c13d | 477 | case EEXIST: |
71a3bb01 | 478 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
bd29c13d DG |
479 | break; |
480 | case ENOSYS: | |
481 | WARN("Event type not implemented"); | |
71a3bb01 | 482 | ret = LTTNG_ERR_KERN_EVENT_ENOSYS; |
bd29c13d | 483 | break; |
8197a339 DG |
484 | case ENOENT: |
485 | WARN("Event %s not found!", ev->name); | |
71a3bb01 | 486 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
8197a339 | 487 | break; |
bd29c13d | 488 | default: |
71a3bb01 | 489 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
d87bfb32 DG |
490 | PERROR("create event ioctl"); |
491 | } | |
e953ef25 | 492 | goto free_event; |
8c0faa1d | 493 | } |
f34daff7 | 494 | |
d0ae4ea8 | 495 | event->type = ev->type; |
71a3bb01 | 496 | event->fd = fd; |
7b395890 | 497 | /* Prevent fd duplication after execlp() */ |
71a3bb01 FD |
498 | err = fcntl(event->fd, F_SETFD, FD_CLOEXEC); |
499 | if (err < 0) { | |
df0f840b | 500 | PERROR("fcntl session fd"); |
7b395890 DG |
501 | } |
502 | ||
00a62084 | 503 | if (filter) { |
71a3bb01 FD |
504 | err = kernctl_filter(event->fd, filter); |
505 | if (err < 0) { | |
506 | switch (-err) { | |
507 | case ENOMEM: | |
508 | ret = LTTNG_ERR_FILTER_NOMEM; | |
509 | break; | |
510 | default: | |
511 | ret = LTTNG_ERR_FILTER_INVAL; | |
512 | break; | |
513 | } | |
00a62084 MD |
514 | goto filter_error; |
515 | } | |
516 | } | |
517 | ||
dcabc190 FD |
518 | if (ev->type == LTTNG_EVENT_USERSPACE_PROBE) { |
519 | ret = userspace_probe_add_callsites(ev, channel->session, event->fd); | |
520 | if (ret) { | |
521 | goto add_callsite_error; | |
522 | } | |
523 | } | |
524 | ||
71a3bb01 FD |
525 | err = kernctl_enable(event->fd); |
526 | if (err < 0) { | |
527 | switch (-err) { | |
00a62084 MD |
528 | case EEXIST: |
529 | ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
530 | break; | |
531 | default: | |
532 | PERROR("enable kernel event"); | |
71a3bb01 | 533 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
00a62084 MD |
534 | break; |
535 | } | |
536 | goto enable_error; | |
537 | } | |
538 | ||
f3ed775e DG |
539 | /* Add event to event list */ |
540 | cds_list_add(&event->list, &channel->events_list.head); | |
cbbbb275 DG |
541 | channel->event_count++; |
542 | ||
e953ef25 DG |
543 | DBG("Event %s created (fd: %d)", ev->name, event->fd); |
544 | ||
545 | return 0; | |
546 | ||
dcabc190 | 547 | add_callsite_error: |
00a62084 MD |
548 | enable_error: |
549 | filter_error: | |
550 | { | |
551 | int closeret; | |
552 | ||
553 | closeret = close(event->fd); | |
554 | if (closeret) { | |
555 | PERROR("close event fd"); | |
556 | } | |
557 | } | |
e953ef25 DG |
558 | free_event: |
559 | free(event); | |
560 | error: | |
d87bfb32 | 561 | return ret; |
e953ef25 DG |
562 | } |
563 | ||
26cc6b4e | 564 | /* |
050349bb | 565 | * Disable a kernel channel. |
26cc6b4e DG |
566 | */ |
567 | int kernel_disable_channel(struct ltt_kernel_channel *chan) | |
568 | { | |
569 | int ret; | |
570 | ||
0525e9ae DG |
571 | assert(chan); |
572 | ||
26cc6b4e DG |
573 | ret = kernctl_disable(chan->fd); |
574 | if (ret < 0) { | |
df0f840b | 575 | PERROR("disable chan ioctl"); |
26cc6b4e DG |
576 | goto error; |
577 | } | |
578 | ||
579 | chan->enabled = 0; | |
e1f3997a JD |
580 | DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")", |
581 | chan->channel->name, chan->fd, chan->key); | |
26cc6b4e DG |
582 | |
583 | return 0; | |
584 | ||
585 | error: | |
586 | return ret; | |
587 | } | |
588 | ||
d36b8583 | 589 | /* |
050349bb | 590 | * Enable a kernel channel. |
d36b8583 DG |
591 | */ |
592 | int kernel_enable_channel(struct ltt_kernel_channel *chan) | |
593 | { | |
594 | int ret; | |
595 | ||
0525e9ae DG |
596 | assert(chan); |
597 | ||
d36b8583 | 598 | ret = kernctl_enable(chan->fd); |
32af2c95 | 599 | if (ret < 0 && ret != -EEXIST) { |
df0f840b | 600 | PERROR("Enable kernel chan"); |
d36b8583 DG |
601 | goto error; |
602 | } | |
603 | ||
604 | chan->enabled = 1; | |
e1f3997a JD |
605 | DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")", |
606 | chan->channel->name, chan->fd, chan->key); | |
d36b8583 DG |
607 | |
608 | return 0; | |
609 | ||
610 | error: | |
611 | return ret; | |
612 | } | |
613 | ||
19e70852 | 614 | /* |
050349bb | 615 | * Enable a kernel event. |
19e70852 DG |
616 | */ |
617 | int kernel_enable_event(struct ltt_kernel_event *event) | |
618 | { | |
619 | int ret; | |
620 | ||
0525e9ae DG |
621 | assert(event); |
622 | ||
19e70852 | 623 | ret = kernctl_enable(event->fd); |
42224349 | 624 | if (ret < 0) { |
32af2c95 | 625 | switch (-ret) { |
42224349 | 626 | case EEXIST: |
f73fabfd | 627 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
628 | break; |
629 | default: | |
630 | PERROR("enable kernel event"); | |
631 | break; | |
632 | } | |
19e70852 DG |
633 | goto error; |
634 | } | |
635 | ||
636 | event->enabled = 1; | |
637 | DBG("Kernel event %s enabled (fd: %d)", event->event->name, event->fd); | |
638 | ||
639 | return 0; | |
640 | ||
641 | error: | |
d36b8583 | 642 | return ret; |
19e70852 DG |
643 | } |
644 | ||
e953ef25 | 645 | /* |
050349bb | 646 | * Disable a kernel event. |
e953ef25 | 647 | */ |
19e70852 | 648 | int kernel_disable_event(struct ltt_kernel_event *event) |
e953ef25 DG |
649 | { |
650 | int ret; | |
19e70852 | 651 | |
0525e9ae DG |
652 | assert(event); |
653 | ||
19e70852 | 654 | ret = kernctl_disable(event->fd); |
42224349 | 655 | if (ret < 0) { |
32af2c95 | 656 | switch (-ret) { |
42224349 | 657 | case EEXIST: |
f73fabfd | 658 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
659 | break; |
660 | default: | |
661 | PERROR("disable kernel event"); | |
662 | break; | |
663 | } | |
19e70852 | 664 | goto error; |
e953ef25 | 665 | } |
f3ed775e | 666 | |
19e70852 DG |
667 | event->enabled = 0; |
668 | DBG("Kernel event %s disabled (fd: %d)", event->event->name, event->fd); | |
669 | ||
f34daff7 DG |
670 | return 0; |
671 | ||
672 | error: | |
d36b8583 | 673 | return ret; |
f34daff7 | 674 | } |
aaf26714 | 675 | |
6e911cad | 676 | |
ccf10263 MD |
677 | int kernel_track_pid(struct ltt_kernel_session *session, int pid) |
678 | { | |
7c493d31 MD |
679 | int ret; |
680 | ||
ccf10263 MD |
681 | DBG("Kernel track PID %d for session id %" PRIu64 ".", |
682 | pid, session->id); | |
7c493d31 MD |
683 | ret = kernctl_track_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 EEXIST: | |
693 | return LTTNG_ERR_PID_TRACKED; | |
694 | default: | |
695 | return LTTNG_ERR_UNK; | |
696 | } | |
ccf10263 MD |
697 | } |
698 | ||
699 | int kernel_untrack_pid(struct ltt_kernel_session *session, int pid) | |
700 | { | |
7c493d31 MD |
701 | int ret; |
702 | ||
ccf10263 MD |
703 | DBG("Kernel untrack PID %d for session id %" PRIu64 ".", |
704 | pid, session->id); | |
7c493d31 MD |
705 | ret = kernctl_untrack_pid(session->fd, pid); |
706 | if (!ret) { | |
707 | return LTTNG_OK; | |
708 | } | |
32af2c95 | 709 | switch (-ret) { |
7c493d31 MD |
710 | case EINVAL: |
711 | return LTTNG_ERR_INVALID; | |
712 | case ENOMEM: | |
713 | return LTTNG_ERR_NOMEM; | |
714 | case ENOENT: | |
715 | return LTTNG_ERR_PID_NOT_TRACKED; | |
716 | default: | |
717 | return LTTNG_ERR_UNK; | |
718 | } | |
ccf10263 MD |
719 | } |
720 | ||
a5dfbb9d MD |
721 | ssize_t kernel_list_tracker_pids(struct ltt_kernel_session *session, |
722 | int **_pids) | |
723 | { | |
724 | int fd, ret; | |
725 | int pid; | |
726 | ssize_t nbmem, count = 0; | |
727 | FILE *fp; | |
728 | int *pids; | |
729 | ||
730 | fd = kernctl_list_tracker_pids(session->fd); | |
731 | if (fd < 0) { | |
732 | PERROR("kernel tracker pids list"); | |
733 | goto error; | |
734 | } | |
735 | ||
736 | fp = fdopen(fd, "r"); | |
737 | if (fp == NULL) { | |
738 | PERROR("kernel tracker pids list fdopen"); | |
739 | goto error_fp; | |
740 | } | |
741 | ||
742 | nbmem = KERNEL_TRACKER_PIDS_INIT_LIST_SIZE; | |
743 | pids = zmalloc(sizeof(*pids) * nbmem); | |
744 | if (pids == NULL) { | |
745 | PERROR("alloc list pids"); | |
746 | count = -ENOMEM; | |
747 | goto end; | |
748 | } | |
749 | ||
750 | while (fscanf(fp, "process { pid = %u; };\n", &pid) == 1) { | |
751 | if (count >= nbmem) { | |
752 | int *new_pids; | |
753 | size_t new_nbmem; | |
754 | ||
755 | new_nbmem = nbmem << 1; | |
756 | DBG("Reallocating pids list from %zu to %zu entries", | |
757 | nbmem, new_nbmem); | |
758 | new_pids = realloc(pids, new_nbmem * sizeof(*new_pids)); | |
759 | if (new_pids == NULL) { | |
760 | PERROR("realloc list events"); | |
761 | free(pids); | |
762 | count = -ENOMEM; | |
763 | goto end; | |
764 | } | |
765 | /* Zero the new memory */ | |
766 | memset(new_pids + nbmem, 0, | |
767 | (new_nbmem - nbmem) * sizeof(*new_pids)); | |
768 | nbmem = new_nbmem; | |
769 | pids = new_pids; | |
770 | } | |
771 | pids[count++] = pid; | |
772 | } | |
773 | ||
774 | *_pids = pids; | |
775 | DBG("Kernel list tracker pids done (%zd pids)", count); | |
776 | end: | |
777 | ret = fclose(fp); /* closes both fp and fd */ | |
778 | if (ret) { | |
779 | PERROR("fclose"); | |
780 | } | |
781 | return count; | |
782 | ||
783 | error_fp: | |
784 | ret = close(fd); | |
785 | if (ret) { | |
786 | PERROR("close"); | |
787 | } | |
788 | error: | |
789 | return -1; | |
790 | } | |
791 | ||
aaf26714 | 792 | /* |
050349bb DG |
793 | * Create kernel metadata, open from the kernel tracer and add it to the |
794 | * kernel session. | |
aaf26714 | 795 | */ |
a4b92340 | 796 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
797 | { |
798 | int ret; | |
74024a21 | 799 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 800 | |
0525e9ae DG |
801 | assert(session); |
802 | ||
54012638 | 803 | /* Allocate kernel metadata */ |
a4b92340 | 804 | lkm = trace_kernel_create_metadata(); |
54012638 | 805 | if (lkm == NULL) { |
aaf26714 DG |
806 | goto error; |
807 | } | |
808 | ||
54012638 | 809 | /* Kernel tracer metadata creation */ |
f3ed775e | 810 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 811 | if (ret < 0) { |
74024a21 | 812 | goto error_open; |
aaf26714 DG |
813 | } |
814 | ||
8c0faa1d | 815 | lkm->fd = ret; |
d40f0359 | 816 | lkm->key = ++next_kernel_channel_key; |
7b395890 DG |
817 | /* Prevent fd duplication after execlp() */ |
818 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
819 | if (ret < 0) { | |
df0f840b | 820 | PERROR("fcntl session fd"); |
7b395890 DG |
821 | } |
822 | ||
aaf26714 | 823 | session->metadata = lkm; |
8c0faa1d | 824 | |
00e2e675 | 825 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
826 | |
827 | return 0; | |
828 | ||
74024a21 DG |
829 | error_open: |
830 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 831 | error: |
54012638 | 832 | return -1; |
8c0faa1d DG |
833 | } |
834 | ||
835 | /* | |
050349bb | 836 | * Start tracing session. |
8c0faa1d DG |
837 | */ |
838 | int kernel_start_session(struct ltt_kernel_session *session) | |
839 | { | |
840 | int ret; | |
841 | ||
0525e9ae DG |
842 | assert(session); |
843 | ||
8c0faa1d DG |
844 | ret = kernctl_start_session(session->fd); |
845 | if (ret < 0) { | |
df0f840b | 846 | PERROR("ioctl start session"); |
8c0faa1d DG |
847 | goto error; |
848 | } | |
849 | ||
850 | DBG("Kernel session started"); | |
851 | ||
852 | return 0; | |
853 | ||
854 | error: | |
855 | return ret; | |
856 | } | |
857 | ||
f3ed775e | 858 | /* |
050349bb | 859 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e | 860 | */ |
7d268848 | 861 | void kernel_wait_quiescent(void) |
f3ed775e DG |
862 | { |
863 | int ret; | |
7d268848 | 864 | int fd = kernel_tracer_fd; |
f3ed775e DG |
865 | |
866 | DBG("Kernel quiescent wait on %d", fd); | |
867 | ||
868 | ret = kernctl_wait_quiescent(fd); | |
869 | if (ret < 0) { | |
df0f840b | 870 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
871 | ERR("Kernel quiescent wait failed"); |
872 | } | |
873 | } | |
874 | ||
875 | /* | |
f3ed775e DG |
876 | * Force flush buffer of metadata. |
877 | */ | |
878 | int kernel_metadata_flush_buffer(int fd) | |
879 | { | |
880 | int ret; | |
881 | ||
169d2cb7 DG |
882 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
883 | ||
f3ed775e DG |
884 | ret = kernctl_buffer_flush(fd); |
885 | if (ret < 0) { | |
00e2e675 | 886 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
887 | } |
888 | ||
889 | return 0; | |
890 | } | |
891 | ||
892 | /* | |
050349bb | 893 | * Force flush buffer for channel. |
f3ed775e DG |
894 | */ |
895 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
896 | { | |
897 | int ret; | |
898 | struct ltt_kernel_stream *stream; | |
899 | ||
0525e9ae DG |
900 | assert(channel); |
901 | ||
f3ed775e DG |
902 | DBG("Flush buffer for channel %s", channel->channel->name); |
903 | ||
904 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
905 | DBG("Flushing channel stream %d", stream->fd); | |
906 | ret = kernctl_buffer_flush(stream->fd); | |
907 | if (ret < 0) { | |
df0f840b | 908 | PERROR("ioctl"); |
f3ed775e DG |
909 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
910 | stream->fd, ret); | |
911 | } | |
912 | } | |
913 | ||
914 | return 0; | |
915 | } | |
916 | ||
8c0faa1d | 917 | /* |
050349bb | 918 | * Stop tracing session. |
8c0faa1d DG |
919 | */ |
920 | int kernel_stop_session(struct ltt_kernel_session *session) | |
921 | { | |
922 | int ret; | |
923 | ||
0525e9ae DG |
924 | assert(session); |
925 | ||
8c0faa1d DG |
926 | ret = kernctl_stop_session(session->fd); |
927 | if (ret < 0) { | |
928 | goto error; | |
929 | } | |
930 | ||
931 | DBG("Kernel session stopped"); | |
932 | ||
933 | return 0; | |
934 | ||
935 | error: | |
936 | return ret; | |
937 | } | |
938 | ||
939 | /* | |
050349bb DG |
940 | * Open stream of channel, register it to the kernel tracer and add it |
941 | * to the stream list of the channel. | |
8c0faa1d | 942 | * |
1cfb4b98 MD |
943 | * Note: given that the streams may appear in random order wrt CPU |
944 | * number (e.g. cpu hotplug), the index value of the stream number in | |
945 | * the stream name is not necessarily linked to the CPU number. | |
946 | * | |
050349bb | 947 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 948 | */ |
f3ed775e | 949 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 950 | { |
1cfb4b98 | 951 | int ret; |
8c0faa1d DG |
952 | struct ltt_kernel_stream *lks; |
953 | ||
0525e9ae DG |
954 | assert(channel); |
955 | ||
5a47c6a2 | 956 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
957 | lks = trace_kernel_create_stream(channel->channel->name, |
958 | channel->stream_count); | |
8c0faa1d | 959 | if (lks == NULL) { |
799e2c4f MD |
960 | ret = close(ret); |
961 | if (ret) { | |
962 | PERROR("close"); | |
963 | } | |
8c0faa1d DG |
964 | goto error; |
965 | } | |
966 | ||
967 | lks->fd = ret; | |
7b395890 DG |
968 | /* Prevent fd duplication after execlp() */ |
969 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
970 | if (ret < 0) { | |
df0f840b | 971 | PERROR("fcntl session fd"); |
7b395890 DG |
972 | } |
973 | ||
1624d5b7 JD |
974 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
975 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
976 | ||
1cfb4b98 | 977 | /* Add stream to channel stream list */ |
8c0faa1d DG |
978 | cds_list_add(&lks->list, &channel->stream_list.head); |
979 | channel->stream_count++; | |
8c0faa1d | 980 | |
00e2e675 DG |
981 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
982 | lks->state); | |
54012638 | 983 | } |
8c0faa1d DG |
984 | |
985 | return channel->stream_count; | |
986 | ||
987 | error: | |
54012638 | 988 | return -1; |
8c0faa1d DG |
989 | } |
990 | ||
991 | /* | |
050349bb | 992 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 993 | */ |
f3ed775e | 994 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
995 | { |
996 | int ret; | |
997 | ||
0525e9ae DG |
998 | assert(session); |
999 | ||
8c0faa1d DG |
1000 | ret = kernctl_create_stream(session->metadata->fd); |
1001 | if (ret < 0) { | |
df0f840b | 1002 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
1003 | goto error; |
1004 | } | |
1005 | ||
1006 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
1007 | session->metadata_stream_fd = ret; | |
7b395890 DG |
1008 | /* Prevent fd duplication after execlp() */ |
1009 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
1010 | if (ret < 0) { | |
df0f840b | 1011 | PERROR("fcntl session fd"); |
7b395890 | 1012 | } |
aaf26714 DG |
1013 | |
1014 | return 0; | |
1015 | ||
1016 | error: | |
54012638 | 1017 | return -1; |
aaf26714 | 1018 | } |
2ef84c95 DG |
1019 | |
1020 | /* | |
9f19cc17 | 1021 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 1022 | */ |
7d268848 | 1023 | ssize_t kernel_list_events(struct lttng_event **events) |
2ef84c95 | 1024 | { |
53efb85a | 1025 | int fd, ret; |
9f19cc17 DG |
1026 | char *event; |
1027 | size_t nbmem, count = 0; | |
2ef84c95 | 1028 | FILE *fp; |
9f19cc17 | 1029 | struct lttng_event *elist; |
2ef84c95 | 1030 | |
0525e9ae DG |
1031 | assert(events); |
1032 | ||
7d268848 | 1033 | fd = kernctl_tracepoint_list(kernel_tracer_fd); |
2ef84c95 | 1034 | if (fd < 0) { |
df0f840b | 1035 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
1036 | goto error; |
1037 | } | |
1038 | ||
1039 | fp = fdopen(fd, "r"); | |
1040 | if (fp == NULL) { | |
df0f840b | 1041 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 1042 | goto error_fp; |
2ef84c95 DG |
1043 | } |
1044 | ||
1045 | /* | |
1046 | * Init memory size counter | |
1047 | * See kernel-ctl.h for explanation of this value | |
1048 | */ | |
6725fe19 | 1049 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
ba7f0ae5 | 1050 | elist = zmalloc(sizeof(struct lttng_event) * nbmem); |
3b870559 MD |
1051 | if (elist == NULL) { |
1052 | PERROR("alloc list events"); | |
1053 | count = -ENOMEM; | |
1054 | goto end; | |
1055 | } | |
2ef84c95 | 1056 | |
53efb85a | 1057 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 1058 | if (count >= nbmem) { |
3b870559 | 1059 | struct lttng_event *new_elist; |
53efb85a | 1060 | size_t new_nbmem; |
3b870559 | 1061 | |
53efb85a MD |
1062 | new_nbmem = nbmem << 1; |
1063 | DBG("Reallocating event list from %zu to %zu bytes", | |
1064 | nbmem, new_nbmem); | |
1065 | new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event)); | |
3b870559 | 1066 | if (new_elist == NULL) { |
df0f840b | 1067 | PERROR("realloc list events"); |
3b870559 MD |
1068 | free(event); |
1069 | free(elist); | |
61b73b12 MD |
1070 | count = -ENOMEM; |
1071 | goto end; | |
2ef84c95 | 1072 | } |
53efb85a MD |
1073 | /* Zero the new memory */ |
1074 | memset(new_elist + nbmem, 0, | |
1075 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
1076 | nbmem = new_nbmem; | |
3b870559 | 1077 | elist = new_elist; |
2ef84c95 | 1078 | } |
99497cd0 MD |
1079 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
1080 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 1081 | elist[count].enabled = -1; |
9f19cc17 | 1082 | count++; |
3b870559 | 1083 | free(event); |
2ef84c95 DG |
1084 | } |
1085 | ||
9f19cc17 | 1086 | *events = elist; |
ced2f820 | 1087 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 1088 | end: |
799e2c4f MD |
1089 | ret = fclose(fp); /* closes both fp and fd */ |
1090 | if (ret) { | |
1091 | PERROR("fclose"); | |
1092 | } | |
9f19cc17 | 1093 | return count; |
2ef84c95 | 1094 | |
61b73b12 | 1095 | error_fp: |
799e2c4f MD |
1096 | ret = close(fd); |
1097 | if (ret) { | |
1098 | PERROR("close"); | |
1099 | } | |
2ef84c95 DG |
1100 | error: |
1101 | return -1; | |
1102 | } | |
096102bd DG |
1103 | |
1104 | /* | |
1105 | * Get kernel version and validate it. | |
1106 | */ | |
7d268848 | 1107 | int kernel_validate_version(struct lttng_kernel_tracer_version *version, |
88076e89 | 1108 | struct lttng_kernel_tracer_abi_version *abi_version) |
096102bd DG |
1109 | { |
1110 | int ret; | |
096102bd | 1111 | |
7d268848 | 1112 | ret = kernctl_tracer_version(kernel_tracer_fd, version); |
096102bd | 1113 | if (ret < 0) { |
521dd134 | 1114 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
1115 | goto error; |
1116 | } | |
1117 | ||
1118 | /* Validate version */ | |
88076e89 | 1119 | if (version->major != VERSION_MAJOR) { |
c052142c | 1120 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", |
88076e89 | 1121 | version->major, VERSION_MAJOR); |
096102bd | 1122 | goto error_version; |
096102bd | 1123 | } |
7d268848 | 1124 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, abi_version); |
c052142c | 1125 | if (ret < 0) { |
521dd134 | 1126 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
1127 | goto error; |
1128 | } | |
88076e89 | 1129 | if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) { |
521dd134 | 1130 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
88076e89 | 1131 | abi_version->major, abi_version->minor, |
c052142c MD |
1132 | LTTNG_MODULES_ABI_MAJOR_VERSION); |
1133 | goto error; | |
1134 | } | |
1135 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
88076e89 JD |
1136 | version->major, version->minor, |
1137 | abi_version->major, abi_version->minor); | |
096102bd DG |
1138 | return 0; |
1139 | ||
1140 | error_version: | |
096102bd DG |
1141 | ret = -1; |
1142 | ||
1143 | error: | |
521dd134 | 1144 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
1145 | return ret; |
1146 | } | |
335a95b7 MD |
1147 | |
1148 | /* | |
1149 | * Kernel work-arounds called at the start of sessiond main(). | |
1150 | */ | |
1151 | int init_kernel_workarounds(void) | |
1152 | { | |
8936c33a | 1153 | int ret; |
335a95b7 MD |
1154 | FILE *fp; |
1155 | ||
1156 | /* | |
1157 | * boot_id needs to be read once before being used concurrently | |
1158 | * to deal with a Linux kernel race. A fix is proposed for | |
1159 | * upstream, but the work-around is needed for older kernels. | |
1160 | */ | |
1161 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
1162 | if (!fp) { | |
1163 | goto end_boot_id; | |
1164 | } | |
1165 | while (!feof(fp)) { | |
1166 | char buf[37] = ""; | |
1167 | ||
8936c33a DG |
1168 | ret = fread(buf, 1, sizeof(buf), fp); |
1169 | if (ret < 0) { | |
1170 | /* Ignore error, we don't really care */ | |
1171 | } | |
335a95b7 | 1172 | } |
799e2c4f MD |
1173 | ret = fclose(fp); |
1174 | if (ret) { | |
1175 | PERROR("fclose"); | |
1176 | } | |
335a95b7 | 1177 | end_boot_id: |
335a95b7 MD |
1178 | return 0; |
1179 | } | |
2f77fc4b DG |
1180 | |
1181 | /* | |
d070c424 | 1182 | * Teardown of a kernel session, keeping data required by destroy notifiers. |
2f77fc4b DG |
1183 | */ |
1184 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
1185 | { | |
82b69413 JG |
1186 | struct lttng_trace_chunk *trace_chunk; |
1187 | ||
2f77fc4b DG |
1188 | if (ksess == NULL) { |
1189 | DBG3("No kernel session when tearing down session"); | |
1190 | return; | |
1191 | } | |
1192 | ||
1193 | DBG("Tearing down kernel session"); | |
82b69413 | 1194 | trace_chunk = ksess->current_trace_chunk; |
2f77fc4b | 1195 | |
07b86b52 | 1196 | /* |
15dc512a DG |
1197 | * Destroy channels on the consumer if at least one FD has been sent and we |
1198 | * are in no output mode because the streams are in *no* monitor mode so we | |
1199 | * have to send a command to clean them up or else they leaked. | |
07b86b52 | 1200 | */ |
15dc512a | 1201 | if (!ksess->output_traces && ksess->consumer_fds_sent) { |
07b86b52 JD |
1202 | int ret; |
1203 | struct consumer_socket *socket; | |
1204 | struct lttng_ht_iter iter; | |
1205 | ||
1206 | /* For each consumer socket. */ | |
d069d577 | 1207 | rcu_read_lock(); |
07b86b52 JD |
1208 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, |
1209 | socket, node.node) { | |
1210 | struct ltt_kernel_channel *chan; | |
1211 | ||
1212 | /* For each channel, ask the consumer to destroy it. */ | |
1213 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1214 | ret = kernel_consumer_destroy_channel(socket, chan); | |
1215 | if (ret < 0) { | |
1216 | /* Consumer is probably dead. Use next socket. */ | |
1217 | continue; | |
1218 | } | |
1219 | } | |
1220 | } | |
d069d577 | 1221 | rcu_read_unlock(); |
07b86b52 JD |
1222 | } |
1223 | ||
2f77fc4b DG |
1224 | /* Close any relayd session */ |
1225 | consumer_output_send_destroy_relayd(ksess->consumer); | |
1226 | ||
1227 | trace_kernel_destroy_session(ksess); | |
82b69413 | 1228 | lttng_trace_chunk_put(trace_chunk); |
2f77fc4b | 1229 | } |
fb5f35b6 | 1230 | |
d070c424 MD |
1231 | /* Teardown of data required by destroy notifiers. */ |
1232 | void kernel_free_session(struct ltt_kernel_session *ksess) | |
1233 | { | |
1234 | if (ksess == NULL) { | |
1235 | return; | |
1236 | } | |
1237 | trace_kernel_free_session(ksess); | |
1238 | } | |
1239 | ||
fb5f35b6 DG |
1240 | /* |
1241 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
1242 | */ | |
1243 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
1244 | { | |
1245 | struct ltt_kernel_session *ksess = NULL; | |
1246 | ||
1247 | assert(kchan); | |
1248 | assert(kchan->channel); | |
1249 | ||
1250 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
1251 | ||
1252 | /* Update channel count of associated session. */ | |
1253 | if (kchan->session) { | |
1254 | /* Keep pointer reference so we can update it after the destroy. */ | |
1255 | ksess = kchan->session; | |
1256 | } | |
1257 | ||
1258 | trace_kernel_destroy_channel(kchan); | |
1259 | ||
1260 | /* | |
1261 | * At this point the kernel channel is not visible anymore. This is safe | |
1262 | * since in order to work on a visible kernel session, the tracing session | |
1263 | * lock (ltt_session.lock) MUST be acquired. | |
1264 | */ | |
1265 | if (ksess) { | |
1266 | ksess->channel_count--; | |
1267 | } | |
1268 | } | |
6dc3064a DG |
1269 | |
1270 | /* | |
1271 | * Take a snapshot for a given kernel session. | |
1272 | * | |
9a654598 | 1273 | * Return LTTNG_OK on success or else return a LTTNG_ERR code. |
6dc3064a | 1274 | */ |
fb9a95c4 JG |
1275 | enum lttng_error_code kernel_snapshot_record( |
1276 | struct ltt_kernel_session *ksess, | |
348a81dc | 1277 | const struct consumer_output *output, int wait, |
d07ceecd | 1278 | uint64_t nb_packets_per_stream) |
6dc3064a | 1279 | { |
2a06df8d | 1280 | int err, ret, saved_metadata_fd; |
9a654598 | 1281 | enum lttng_error_code status = LTTNG_OK; |
6dc3064a DG |
1282 | struct consumer_socket *socket; |
1283 | struct lttng_ht_iter iter; | |
1284 | struct ltt_kernel_metadata *saved_metadata; | |
3b967712 | 1285 | char *trace_path = NULL; |
6dc3064a DG |
1286 | |
1287 | assert(ksess); | |
1288 | assert(ksess->consumer); | |
1289 | assert(output); | |
1290 | ||
1291 | DBG("Kernel snapshot record started"); | |
1292 | ||
1293 | /* Save current metadata since the following calls will change it. */ | |
1294 | saved_metadata = ksess->metadata; | |
1295 | saved_metadata_fd = ksess->metadata_stream_fd; | |
1296 | ||
1297 | rcu_read_lock(); | |
1298 | ||
1299 | ret = kernel_open_metadata(ksess); | |
1300 | if (ret < 0) { | |
9a654598 | 1301 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1302 | goto error; |
1303 | } | |
1304 | ||
1305 | ret = kernel_open_metadata_stream(ksess); | |
1306 | if (ret < 0) { | |
9a654598 | 1307 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1308 | goto error_open_stream; |
1309 | } | |
1310 | ||
3b967712 MD |
1311 | trace_path = setup_channel_trace_path(ksess->consumer, |
1312 | DEFAULT_KERNEL_TRACE_DIR); | |
1313 | if (!trace_path) { | |
1314 | status = LTTNG_ERR_INVALID; | |
1315 | goto error; | |
1316 | } | |
6dc3064a | 1317 | /* Send metadata to consumer and snapshot everything. */ |
348a81dc | 1318 | cds_lfht_for_each_entry(output->socks->ht, &iter.iter, |
6dc3064a | 1319 | socket, node.node) { |
6dc3064a | 1320 | struct ltt_kernel_channel *chan; |
6dc3064a | 1321 | |
6dc3064a DG |
1322 | pthread_mutex_lock(socket->lock); |
1323 | /* This stream must not be monitored by the consumer. */ | |
07b86b52 | 1324 | ret = kernel_consumer_add_metadata(socket, ksess, 0); |
6dc3064a | 1325 | pthread_mutex_unlock(socket->lock); |
6dc3064a | 1326 | if (ret < 0) { |
0ed78e50 | 1327 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1328 | goto error_consumer; |
1329 | } | |
1330 | ||
1331 | /* For each channel, ask the consumer to snapshot it. */ | |
1332 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
9a654598 | 1333 | status = consumer_snapshot_channel(socket, chan->key, output, 0, |
5c786ded | 1334 | ksess->uid, ksess->gid, |
3b967712 | 1335 | trace_path, wait, |
d2956687 | 1336 | nb_packets_per_stream); |
9a654598 | 1337 | if (status != LTTNG_OK) { |
2a06df8d DG |
1338 | (void) kernel_consumer_destroy_metadata(socket, |
1339 | ksess->metadata); | |
6dc3064a DG |
1340 | goto error_consumer; |
1341 | } | |
1342 | } | |
1343 | ||
1344 | /* Snapshot metadata, */ | |
9a654598 | 1345 | status = consumer_snapshot_channel(socket, ksess->metadata->key, output, |
3b967712 | 1346 | 1, ksess->uid, ksess->gid, trace_path, wait, 0); |
9a654598 | 1347 | if (status != LTTNG_OK) { |
6dc3064a DG |
1348 | goto error_consumer; |
1349 | } | |
07b86b52 JD |
1350 | |
1351 | /* | |
1352 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1353 | * it's not monitored on the consumer side. | |
1354 | */ | |
1355 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1356 | } |
1357 | ||
1358 | error_consumer: | |
1359 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1360 | err = close(ksess->metadata_stream_fd); |
1361 | if (err < 0) { | |
6dc3064a DG |
1362 | PERROR("close snapshot kernel"); |
1363 | } | |
1364 | ||
1365 | error_open_stream: | |
1366 | trace_kernel_destroy_metadata(ksess->metadata); | |
1367 | error: | |
1368 | /* Restore metadata state.*/ | |
1369 | ksess->metadata = saved_metadata; | |
1370 | ksess->metadata_stream_fd = saved_metadata_fd; | |
6dc3064a | 1371 | rcu_read_unlock(); |
3b967712 | 1372 | free(trace_path); |
9a654598 | 1373 | return status; |
6dc3064a | 1374 | } |
834978fd DG |
1375 | |
1376 | /* | |
1377 | * Get the syscall mask array from the kernel tracer. | |
1378 | * | |
1379 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1380 | * be freed. | |
1381 | */ | |
1382 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1383 | { | |
1384 | assert(syscall_mask); | |
1385 | assert(nr_bits); | |
1386 | ||
1387 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1388 | } | |
6e21424e JR |
1389 | |
1390 | /* | |
1391 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1392 | * version number. | |
1393 | * | |
1394 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1395 | * of errors. | |
1396 | */ | |
7d268848 | 1397 | int kernel_supports_ring_buffer_snapshot_sample_positions(void) |
6e21424e JR |
1398 | { |
1399 | int ret = 0; // Not supported by default | |
1400 | struct lttng_kernel_tracer_abi_version abi; | |
1401 | ||
7d268848 | 1402 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, &abi); |
6e21424e JR |
1403 | if (ret < 0) { |
1404 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1405 | goto error; | |
1406 | } | |
1407 | ||
1408 | /* | |
1409 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1410 | */ | |
1411 | if (abi.major >= 2 && abi.minor >= 3) { | |
1412 | /* Supported */ | |
1413 | ret = 1; | |
1414 | } else { | |
1415 | /* Not supported */ | |
1416 | ret = 0; | |
1417 | } | |
1418 | error: | |
1419 | return ret; | |
1420 | } | |
5c408ad8 JD |
1421 | |
1422 | /* | |
1423 | * Rotate a kernel session. | |
1424 | * | |
d5a1b7aa | 1425 | * Return LTTNG_OK on success or else an LTTng error code. |
5c408ad8 | 1426 | */ |
d5a1b7aa | 1427 | enum lttng_error_code kernel_rotate_session(struct ltt_session *session) |
5c408ad8 JD |
1428 | { |
1429 | int ret; | |
d5a1b7aa | 1430 | enum lttng_error_code status = LTTNG_OK; |
5c408ad8 JD |
1431 | struct consumer_socket *socket; |
1432 | struct lttng_ht_iter iter; | |
1433 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1434 | ||
1435 | assert(ksess); | |
1436 | assert(ksess->consumer); | |
1437 | ||
1438 | DBG("Rotate kernel session %s started (session %" PRIu64 ")", | |
1439 | session->name, session->id); | |
1440 | ||
1441 | rcu_read_lock(); | |
1442 | ||
1443 | /* | |
1444 | * Note that this loop will end after one iteration given that there is | |
1445 | * only one kernel consumer. | |
1446 | */ | |
1447 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1448 | socket, node.node) { | |
1449 | struct ltt_kernel_channel *chan; | |
1450 | ||
d2956687 | 1451 | /* For each channel, ask the consumer to rotate it. */ |
5c408ad8 | 1452 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { |
92816cc3 JG |
1453 | DBG("Rotate kernel channel %" PRIu64 ", session %s", |
1454 | chan->key, session->name); | |
5c408ad8 JD |
1455 | ret = consumer_rotate_channel(socket, chan->key, |
1456 | ksess->uid, ksess->gid, ksess->consumer, | |
d2956687 | 1457 | /* is_metadata_channel */ false); |
5c408ad8 | 1458 | if (ret < 0) { |
d5a1b7aa | 1459 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1460 | goto error; |
1461 | } | |
1462 | } | |
1463 | ||
1464 | /* | |
1465 | * Rotate the metadata channel. | |
1466 | */ | |
22a1b931 | 1467 | ret = consumer_rotate_channel(socket, ksess->metadata->key, |
5c408ad8 | 1468 | ksess->uid, ksess->gid, ksess->consumer, |
d2956687 | 1469 | /* is_metadata_channel */ true); |
5c408ad8 | 1470 | if (ret < 0) { |
d5a1b7aa | 1471 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1472 | goto error; |
1473 | } | |
1474 | } | |
1475 | ||
5c408ad8 JD |
1476 | error: |
1477 | rcu_read_unlock(); | |
d5a1b7aa | 1478 | return status; |
5c408ad8 | 1479 | } |
d2956687 JG |
1480 | |
1481 | enum lttng_error_code kernel_create_channel_subdirectories( | |
1482 | const struct ltt_kernel_session *ksess) | |
1483 | { | |
1484 | enum lttng_error_code ret = LTTNG_OK; | |
1485 | enum lttng_trace_chunk_status chunk_status; | |
1486 | ||
1487 | rcu_read_lock(); | |
1488 | assert(ksess->current_trace_chunk); | |
1489 | ||
1490 | /* | |
1491 | * Create the index subdirectory which will take care | |
1492 | * of implicitly creating the channel's path. | |
1493 | */ | |
1494 | chunk_status = lttng_trace_chunk_create_subdirectory( | |
1495 | ksess->current_trace_chunk, | |
1496 | DEFAULT_KERNEL_TRACE_DIR "/" DEFAULT_INDEX_DIR); | |
1497 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { | |
1498 | ret = LTTNG_ERR_CREATE_DIR_FAIL; | |
1499 | goto error; | |
1500 | } | |
1501 | error: | |
1502 | rcu_read_unlock(); | |
1503 | return ret; | |
1504 | } | |
7d268848 MD |
1505 | |
1506 | /* | |
1507 | * Setup necessary data for kernel tracer action. | |
1508 | */ | |
1509 | LTTNG_HIDDEN | |
1510 | int init_kernel_tracer(void) | |
1511 | { | |
1512 | int ret; | |
1513 | bool is_root = !getuid(); | |
1514 | ||
1515 | /* Modprobe lttng kernel modules */ | |
1516 | ret = modprobe_lttng_control(); | |
1517 | if (ret < 0) { | |
1518 | goto error; | |
1519 | } | |
1520 | ||
1521 | /* Open debugfs lttng */ | |
1522 | kernel_tracer_fd = open(module_proc_lttng, O_RDWR); | |
1523 | if (kernel_tracer_fd < 0) { | |
1524 | DBG("Failed to open %s", module_proc_lttng); | |
1525 | goto error_open; | |
1526 | } | |
1527 | ||
1528 | /* Validate kernel version */ | |
1529 | ret = kernel_validate_version(&kernel_tracer_version, | |
1530 | &kernel_tracer_abi_version); | |
1531 | if (ret < 0) { | |
1532 | goto error_version; | |
1533 | } | |
1534 | ||
1535 | ret = modprobe_lttng_data(); | |
1536 | if (ret < 0) { | |
1537 | goto error_modules; | |
1538 | } | |
1539 | ||
1540 | ret = kernel_supports_ring_buffer_snapshot_sample_positions(); | |
1541 | if (ret < 0) { | |
1542 | goto error_modules; | |
1543 | } | |
1544 | ||
1545 | if (ret < 1) { | |
1546 | WARN("Kernel tracer does not support buffer monitoring. " | |
1547 | "The monitoring timer of channels in the kernel domain " | |
1548 | "will be set to 0 (disabled)."); | |
1549 | } | |
1550 | ||
1551 | DBG("Kernel tracer fd %d", kernel_tracer_fd); | |
1552 | ||
1553 | ret = syscall_init_table(kernel_tracer_fd); | |
1554 | if (ret < 0) { | |
1555 | ERR("Unable to populate syscall table. Syscall tracing won't " | |
1556 | "work for this session daemon."); | |
1557 | } | |
1558 | return 0; | |
1559 | ||
1560 | error_version: | |
1561 | modprobe_remove_lttng_control(); | |
1562 | ret = close(kernel_tracer_fd); | |
1563 | if (ret) { | |
1564 | PERROR("close"); | |
1565 | } | |
1566 | kernel_tracer_fd = -1; | |
1567 | return LTTNG_ERR_KERN_VERSION; | |
1568 | ||
1569 | error_modules: | |
1570 | ret = close(kernel_tracer_fd); | |
1571 | if (ret) { | |
1572 | PERROR("close"); | |
1573 | } | |
1574 | ||
1575 | error_open: | |
1576 | modprobe_remove_lttng_control(); | |
1577 | ||
1578 | error: | |
1579 | WARN("No kernel tracer available"); | |
1580 | kernel_tracer_fd = -1; | |
1581 | if (!is_root) { | |
1582 | return LTTNG_ERR_NEED_ROOT_SESSIOND; | |
1583 | } else { | |
1584 | return LTTNG_ERR_KERN_NA; | |
1585 | } | |
1586 | } | |
1587 | ||
1588 | LTTNG_HIDDEN | |
1589 | void cleanup_kernel_tracer(void) | |
1590 | { | |
1591 | int ret; | |
1592 | ||
1593 | DBG2("Closing kernel fd"); | |
1594 | if (kernel_tracer_fd >= 0) { | |
1595 | ret = close(kernel_tracer_fd); | |
1596 | if (ret) { | |
1597 | PERROR("close"); | |
1598 | } | |
1599 | kernel_tracer_fd = -1; | |
1600 | } | |
1601 | DBG("Unloading kernel modules"); | |
1602 | modprobe_remove_lttng_all(); | |
1603 | free(syscall_table); | |
1604 | } | |
1605 | ||
1606 | LTTNG_HIDDEN | |
1607 | bool kernel_tracer_is_initialized(void) | |
1608 | { | |
1609 | return kernel_tracer_fd >= 0; | |
1610 | } |