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 | |
55c9e7ca JR |
682 | static struct lttng_tracker_list *get_id_tracker_list( |
683 | struct ltt_kernel_session *session, | |
684 | enum lttng_tracker_type tracker_type) | |
685 | { | |
686 | switch (tracker_type) { | |
687 | case LTTNG_TRACKER_PID: | |
688 | return session->tracker_list_pid; | |
689 | case LTTNG_TRACKER_VPID: | |
690 | return session->tracker_list_vpid; | |
691 | case LTTNG_TRACKER_UID: | |
692 | return session->tracker_list_uid; | |
693 | case LTTNG_TRACKER_VUID: | |
694 | return session->tracker_list_vuid; | |
695 | case LTTNG_TRACKER_GID: | |
696 | return session->tracker_list_gid; | |
697 | case LTTNG_TRACKER_VGID: | |
698 | return session->tracker_list_vgid; | |
699 | default: | |
700 | return NULL; | |
701 | } | |
702 | } | |
6e911cad | 703 | |
55c9e7ca JR |
704 | int kernel_track_id(enum lttng_tracker_type tracker_type, |
705 | struct ltt_kernel_session *session, | |
706 | const struct lttng_tracker_id *id) | |
ccf10263 | 707 | { |
55c9e7ca JR |
708 | int ret, value; |
709 | struct lttng_tracker_list *tracker_list; | |
2d97a006 JR |
710 | struct lttng_tracker_id **saved_ids; |
711 | ssize_t saved_ids_count; | |
7c493d31 | 712 | |
55c9e7ca JR |
713 | ret = lttng_tracker_id_lookup_string(tracker_type, id, &value); |
714 | if (ret != LTTNG_OK) { | |
715 | return ret; | |
7c493d31 | 716 | } |
55c9e7ca JR |
717 | |
718 | tracker_list = get_id_tracker_list(session, tracker_type); | |
719 | if (!tracker_list) { | |
7c493d31 | 720 | return LTTNG_ERR_INVALID; |
7c493d31 | 721 | } |
ccf10263 | 722 | |
55c9e7ca JR |
723 | /* Save list for restore on error. */ |
724 | saved_ids_count = lttng_tracker_id_get_list(tracker_list, &saved_ids); | |
725 | if (saved_ids_count < 0) { | |
726 | return LTTNG_ERR_INVALID; | |
727 | } | |
7c493d31 | 728 | |
55c9e7ca JR |
729 | /* Add to list. */ |
730 | ret = lttng_tracker_list_add(tracker_list, id); | |
731 | if (ret != LTTNG_OK) { | |
732 | goto end; | |
7c493d31 | 733 | } |
55c9e7ca JR |
734 | |
735 | switch (tracker_type) { | |
736 | case LTTNG_TRACKER_PID: | |
737 | DBG("Kernel track PID %d for session id %" PRIu64 ".", value, | |
738 | session->id); | |
739 | ret = kernctl_track_pid(session->fd, value); | |
740 | if (!ret) { | |
741 | ret = LTTNG_OK; | |
742 | goto end; | |
743 | } | |
744 | break; | |
745 | case LTTNG_TRACKER_VPID: | |
746 | DBG("Kernel track VPID %d for session id %" PRIu64 ".", value, | |
747 | session->id); | |
748 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_VPID, value); | |
749 | if (!ret) { | |
750 | ret = LTTNG_OK; | |
751 | goto end; | |
752 | } | |
753 | break; | |
754 | case LTTNG_TRACKER_UID: | |
755 | DBG("Kernel track UID %d for session id %" PRIu64 ".", value, | |
756 | session->id); | |
757 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_UID, value); | |
758 | if (!ret) { | |
759 | ret = LTTNG_OK; | |
760 | goto end; | |
761 | } | |
762 | break; | |
763 | case LTTNG_TRACKER_GID: | |
764 | DBG("Kernel track GID %d for session id %" PRIu64 ".", value, | |
765 | session->id); | |
766 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_GID, value); | |
767 | if (!ret) { | |
768 | ret = LTTNG_OK; | |
769 | goto end; | |
770 | } | |
771 | break; | |
772 | case LTTNG_TRACKER_VUID: | |
773 | DBG("Kernel track VUID %d for session id %" PRIu64 ".", value, | |
774 | session->id); | |
775 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_VUID, value); | |
776 | if (!ret) { | |
777 | ret = LTTNG_OK; | |
778 | goto end; | |
779 | } | |
780 | break; | |
781 | case LTTNG_TRACKER_VGID: | |
782 | DBG("Kernel track VGID %d for session id %" PRIu64 ".", value, | |
783 | session->id); | |
784 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_VGID, value); | |
785 | if (!ret) { | |
786 | ret = LTTNG_OK; | |
787 | goto end; | |
788 | } | |
789 | break; | |
790 | default: | |
791 | ret = -EINVAL; | |
792 | break; | |
793 | } | |
794 | ||
795 | /* Error handling. */ | |
32af2c95 | 796 | switch (-ret) { |
7c493d31 | 797 | case EINVAL: |
55c9e7ca JR |
798 | ret = LTTNG_ERR_INVALID; |
799 | break; | |
7c493d31 | 800 | case ENOMEM: |
55c9e7ca JR |
801 | ret = LTTNG_ERR_NOMEM; |
802 | break; | |
803 | case EEXIST: | |
804 | ret = LTTNG_ERR_ID_TRACKED; | |
805 | break; | |
7c493d31 | 806 | default: |
55c9e7ca JR |
807 | ret = LTTNG_ERR_UNK; |
808 | break; | |
809 | } | |
810 | ||
811 | if (lttng_tracker_id_set_list(tracker_list, saved_ids, | |
812 | saved_ids_count) != LTTNG_OK) { | |
813 | ERR("Error on tracker add error handling.\n"); | |
7c493d31 | 814 | } |
55c9e7ca | 815 | end: |
2d97a006 | 816 | lttng_tracker_ids_destroy(saved_ids, saved_ids_count); |
55c9e7ca JR |
817 | free(saved_ids); |
818 | return ret; | |
ccf10263 MD |
819 | } |
820 | ||
55c9e7ca JR |
821 | int kernel_untrack_id(enum lttng_tracker_type tracker_type, |
822 | struct ltt_kernel_session *session, | |
823 | const struct lttng_tracker_id *id) | |
a5dfbb9d | 824 | { |
55c9e7ca JR |
825 | int ret, value; |
826 | struct lttng_tracker_list *tracker_list; | |
2d97a006 JR |
827 | struct lttng_tracker_id **saved_ids; |
828 | ssize_t saved_ids_count; | |
a5dfbb9d | 829 | |
55c9e7ca JR |
830 | ret = lttng_tracker_id_lookup_string(tracker_type, id, &value); |
831 | if (ret != LTTNG_OK) { | |
832 | return ret; | |
a5dfbb9d MD |
833 | } |
834 | ||
55c9e7ca JR |
835 | tracker_list = get_id_tracker_list(session, tracker_type); |
836 | if (!tracker_list) { | |
837 | return LTTNG_ERR_INVALID; | |
a5dfbb9d | 838 | } |
55c9e7ca JR |
839 | /* Save list for restore on error. */ |
840 | saved_ids_count = lttng_tracker_id_get_list(tracker_list, &saved_ids); | |
841 | if (saved_ids_count < 0) { | |
842 | return LTTNG_ERR_INVALID; | |
843 | } | |
844 | /* Remove from list. */ | |
845 | ret = lttng_tracker_list_remove(tracker_list, id); | |
846 | if (ret != LTTNG_OK) { | |
a5dfbb9d MD |
847 | goto end; |
848 | } | |
849 | ||
55c9e7ca JR |
850 | switch (tracker_type) { |
851 | case LTTNG_TRACKER_PID: | |
852 | DBG("Kernel untrack PID %d for session id %" PRIu64 ".", value, | |
853 | session->id); | |
854 | ret = kernctl_untrack_pid(session->fd, value); | |
855 | if (!ret) { | |
856 | ret = LTTNG_OK; | |
857 | goto end; | |
858 | } | |
859 | break; | |
860 | case LTTNG_TRACKER_VPID: | |
861 | DBG("Kernel untrack VPID %d for session id %" PRIu64 ".", value, | |
862 | session->id); | |
863 | ret = kernctl_untrack_id( | |
864 | session->fd, LTTNG_TRACKER_VPID, value); | |
865 | if (!ret) { | |
866 | ret = LTTNG_OK; | |
867 | goto end; | |
868 | } | |
869 | break; | |
870 | case LTTNG_TRACKER_UID: | |
871 | DBG("Kernel untrack UID %d for session id %" PRIu64 ".", value, | |
872 | session->id); | |
873 | ret = kernctl_untrack_id(session->fd, LTTNG_TRACKER_UID, value); | |
874 | if (!ret) { | |
875 | ret = LTTNG_OK; | |
876 | goto end; | |
877 | } | |
878 | break; | |
879 | case LTTNG_TRACKER_GID: | |
880 | DBG("Kernel untrack GID %d for session id %" PRIu64 ".", value, | |
881 | session->id); | |
882 | ret = kernctl_untrack_id(session->fd, LTTNG_TRACKER_GID, value); | |
883 | if (!ret) { | |
884 | ret = LTTNG_OK; | |
885 | goto end; | |
886 | } | |
887 | break; | |
888 | case LTTNG_TRACKER_VUID: | |
889 | DBG("Kernel untrack VUID %d for session id %" PRIu64 ".", value, | |
890 | session->id); | |
891 | ret = kernctl_untrack_id( | |
892 | session->fd, LTTNG_TRACKER_VUID, value); | |
893 | if (!ret) { | |
894 | ret = LTTNG_OK; | |
895 | goto end; | |
896 | } | |
897 | break; | |
898 | case LTTNG_TRACKER_VGID: | |
899 | DBG("Kernel untrack VGID %d for session id %" PRIu64 ".", value, | |
900 | session->id); | |
901 | ret = kernctl_untrack_id( | |
902 | session->fd, LTTNG_TRACKER_VGID, value); | |
903 | if (!ret) { | |
904 | ret = LTTNG_OK; | |
905 | goto end; | |
a5dfbb9d | 906 | } |
55c9e7ca JR |
907 | break; |
908 | default: | |
909 | ret = -EINVAL; | |
910 | break; | |
911 | } | |
912 | ||
913 | /* Error handling. */ | |
914 | switch (-ret) { | |
915 | case EINVAL: | |
916 | ret = LTTNG_ERR_INVALID; | |
917 | break; | |
918 | case ENOMEM: | |
919 | ret = LTTNG_ERR_NOMEM; | |
920 | break; | |
921 | case EEXIST: | |
922 | ret = LTTNG_ERR_ID_TRACKED; | |
923 | break; | |
924 | default: | |
925 | ret = LTTNG_ERR_UNK; | |
926 | break; | |
a5dfbb9d MD |
927 | } |
928 | ||
55c9e7ca JR |
929 | if (lttng_tracker_id_set_list(tracker_list, saved_ids, |
930 | saved_ids_count) != LTTNG_OK) { | |
931 | ERR("Error on tracker remove error handling.\n"); | |
932 | } | |
a5dfbb9d | 933 | end: |
2d97a006 | 934 | lttng_tracker_ids_destroy(saved_ids, saved_ids_count); |
55c9e7ca JR |
935 | free(saved_ids); |
936 | return ret; | |
937 | } | |
a5dfbb9d | 938 | |
55c9e7ca JR |
939 | /* |
940 | * Called with session lock held. | |
941 | */ | |
942 | ssize_t kernel_list_tracker_ids(enum lttng_tracker_type tracker_type, | |
943 | struct ltt_kernel_session *session, | |
2d97a006 | 944 | struct lttng_tracker_id ***_ids) |
55c9e7ca JR |
945 | { |
946 | struct lttng_tracker_list *tracker_list; | |
947 | ||
948 | tracker_list = get_id_tracker_list(session, tracker_type); | |
949 | if (!tracker_list) { | |
950 | return -LTTNG_ERR_INVALID; | |
a5dfbb9d | 951 | } |
55c9e7ca | 952 | return lttng_tracker_id_get_list(tracker_list, _ids); |
a5dfbb9d MD |
953 | } |
954 | ||
aaf26714 | 955 | /* |
050349bb DG |
956 | * Create kernel metadata, open from the kernel tracer and add it to the |
957 | * kernel session. | |
aaf26714 | 958 | */ |
a4b92340 | 959 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
960 | { |
961 | int ret; | |
74024a21 | 962 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 963 | |
0525e9ae DG |
964 | assert(session); |
965 | ||
54012638 | 966 | /* Allocate kernel metadata */ |
a4b92340 | 967 | lkm = trace_kernel_create_metadata(); |
54012638 | 968 | if (lkm == NULL) { |
aaf26714 DG |
969 | goto error; |
970 | } | |
971 | ||
54012638 | 972 | /* Kernel tracer metadata creation */ |
f3ed775e | 973 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 974 | if (ret < 0) { |
74024a21 | 975 | goto error_open; |
aaf26714 DG |
976 | } |
977 | ||
8c0faa1d | 978 | lkm->fd = ret; |
d40f0359 | 979 | lkm->key = ++next_kernel_channel_key; |
7b395890 DG |
980 | /* Prevent fd duplication after execlp() */ |
981 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
982 | if (ret < 0) { | |
df0f840b | 983 | PERROR("fcntl session fd"); |
7b395890 DG |
984 | } |
985 | ||
aaf26714 | 986 | session->metadata = lkm; |
8c0faa1d | 987 | |
00e2e675 | 988 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
989 | |
990 | return 0; | |
991 | ||
74024a21 DG |
992 | error_open: |
993 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 994 | error: |
54012638 | 995 | return -1; |
8c0faa1d DG |
996 | } |
997 | ||
998 | /* | |
050349bb | 999 | * Start tracing session. |
8c0faa1d DG |
1000 | */ |
1001 | int kernel_start_session(struct ltt_kernel_session *session) | |
1002 | { | |
1003 | int ret; | |
1004 | ||
0525e9ae DG |
1005 | assert(session); |
1006 | ||
8c0faa1d DG |
1007 | ret = kernctl_start_session(session->fd); |
1008 | if (ret < 0) { | |
df0f840b | 1009 | PERROR("ioctl start session"); |
8c0faa1d DG |
1010 | goto error; |
1011 | } | |
1012 | ||
1013 | DBG("Kernel session started"); | |
1014 | ||
1015 | return 0; | |
1016 | ||
1017 | error: | |
1018 | return ret; | |
1019 | } | |
1020 | ||
f3ed775e | 1021 | /* |
050349bb | 1022 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e | 1023 | */ |
7d268848 | 1024 | void kernel_wait_quiescent(void) |
f3ed775e DG |
1025 | { |
1026 | int ret; | |
7d268848 | 1027 | int fd = kernel_tracer_fd; |
f3ed775e DG |
1028 | |
1029 | DBG("Kernel quiescent wait on %d", fd); | |
1030 | ||
1031 | ret = kernctl_wait_quiescent(fd); | |
1032 | if (ret < 0) { | |
df0f840b | 1033 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
1034 | ERR("Kernel quiescent wait failed"); |
1035 | } | |
1036 | } | |
1037 | ||
1038 | /* | |
f3ed775e DG |
1039 | * Force flush buffer of metadata. |
1040 | */ | |
1041 | int kernel_metadata_flush_buffer(int fd) | |
1042 | { | |
1043 | int ret; | |
1044 | ||
169d2cb7 DG |
1045 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
1046 | ||
f3ed775e DG |
1047 | ret = kernctl_buffer_flush(fd); |
1048 | if (ret < 0) { | |
00e2e675 | 1049 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
1050 | } |
1051 | ||
1052 | return 0; | |
1053 | } | |
1054 | ||
1055 | /* | |
050349bb | 1056 | * Force flush buffer for channel. |
f3ed775e DG |
1057 | */ |
1058 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
1059 | { | |
1060 | int ret; | |
1061 | struct ltt_kernel_stream *stream; | |
1062 | ||
0525e9ae DG |
1063 | assert(channel); |
1064 | ||
f3ed775e DG |
1065 | DBG("Flush buffer for channel %s", channel->channel->name); |
1066 | ||
1067 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
1068 | DBG("Flushing channel stream %d", stream->fd); | |
1069 | ret = kernctl_buffer_flush(stream->fd); | |
1070 | if (ret < 0) { | |
df0f840b | 1071 | PERROR("ioctl"); |
f3ed775e DG |
1072 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
1073 | stream->fd, ret); | |
1074 | } | |
1075 | } | |
1076 | ||
1077 | return 0; | |
1078 | } | |
1079 | ||
8c0faa1d | 1080 | /* |
050349bb | 1081 | * Stop tracing session. |
8c0faa1d DG |
1082 | */ |
1083 | int kernel_stop_session(struct ltt_kernel_session *session) | |
1084 | { | |
1085 | int ret; | |
1086 | ||
0525e9ae DG |
1087 | assert(session); |
1088 | ||
8c0faa1d DG |
1089 | ret = kernctl_stop_session(session->fd); |
1090 | if (ret < 0) { | |
1091 | goto error; | |
1092 | } | |
1093 | ||
1094 | DBG("Kernel session stopped"); | |
1095 | ||
1096 | return 0; | |
1097 | ||
1098 | error: | |
1099 | return ret; | |
1100 | } | |
1101 | ||
1102 | /* | |
050349bb DG |
1103 | * Open stream of channel, register it to the kernel tracer and add it |
1104 | * to the stream list of the channel. | |
8c0faa1d | 1105 | * |
1cfb4b98 MD |
1106 | * Note: given that the streams may appear in random order wrt CPU |
1107 | * number (e.g. cpu hotplug), the index value of the stream number in | |
1108 | * the stream name is not necessarily linked to the CPU number. | |
1109 | * | |
050349bb | 1110 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 1111 | */ |
f3ed775e | 1112 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 1113 | { |
1cfb4b98 | 1114 | int ret; |
8c0faa1d DG |
1115 | struct ltt_kernel_stream *lks; |
1116 | ||
0525e9ae DG |
1117 | assert(channel); |
1118 | ||
5a47c6a2 | 1119 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
1120 | lks = trace_kernel_create_stream(channel->channel->name, |
1121 | channel->stream_count); | |
8c0faa1d | 1122 | if (lks == NULL) { |
799e2c4f MD |
1123 | ret = close(ret); |
1124 | if (ret) { | |
1125 | PERROR("close"); | |
1126 | } | |
8c0faa1d DG |
1127 | goto error; |
1128 | } | |
1129 | ||
1130 | lks->fd = ret; | |
7b395890 DG |
1131 | /* Prevent fd duplication after execlp() */ |
1132 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
1133 | if (ret < 0) { | |
df0f840b | 1134 | PERROR("fcntl session fd"); |
7b395890 DG |
1135 | } |
1136 | ||
1624d5b7 JD |
1137 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
1138 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
1139 | ||
1cfb4b98 | 1140 | /* Add stream to channel stream list */ |
8c0faa1d DG |
1141 | cds_list_add(&lks->list, &channel->stream_list.head); |
1142 | channel->stream_count++; | |
8c0faa1d | 1143 | |
00e2e675 DG |
1144 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
1145 | lks->state); | |
54012638 | 1146 | } |
8c0faa1d DG |
1147 | |
1148 | return channel->stream_count; | |
1149 | ||
1150 | error: | |
54012638 | 1151 | return -1; |
8c0faa1d DG |
1152 | } |
1153 | ||
1154 | /* | |
050349bb | 1155 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 1156 | */ |
f3ed775e | 1157 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
1158 | { |
1159 | int ret; | |
1160 | ||
0525e9ae DG |
1161 | assert(session); |
1162 | ||
8c0faa1d DG |
1163 | ret = kernctl_create_stream(session->metadata->fd); |
1164 | if (ret < 0) { | |
df0f840b | 1165 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
1166 | goto error; |
1167 | } | |
1168 | ||
1169 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
1170 | session->metadata_stream_fd = ret; | |
7b395890 DG |
1171 | /* Prevent fd duplication after execlp() */ |
1172 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
1173 | if (ret < 0) { | |
df0f840b | 1174 | PERROR("fcntl session fd"); |
7b395890 | 1175 | } |
aaf26714 DG |
1176 | |
1177 | return 0; | |
1178 | ||
1179 | error: | |
54012638 | 1180 | return -1; |
aaf26714 | 1181 | } |
2ef84c95 DG |
1182 | |
1183 | /* | |
9f19cc17 | 1184 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 1185 | */ |
7d268848 | 1186 | ssize_t kernel_list_events(struct lttng_event **events) |
2ef84c95 | 1187 | { |
53efb85a | 1188 | int fd, ret; |
9f19cc17 DG |
1189 | char *event; |
1190 | size_t nbmem, count = 0; | |
2ef84c95 | 1191 | FILE *fp; |
9f19cc17 | 1192 | struct lttng_event *elist; |
2ef84c95 | 1193 | |
0525e9ae DG |
1194 | assert(events); |
1195 | ||
7d268848 | 1196 | fd = kernctl_tracepoint_list(kernel_tracer_fd); |
2ef84c95 | 1197 | if (fd < 0) { |
df0f840b | 1198 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
1199 | goto error; |
1200 | } | |
1201 | ||
1202 | fp = fdopen(fd, "r"); | |
1203 | if (fp == NULL) { | |
df0f840b | 1204 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 1205 | goto error_fp; |
2ef84c95 DG |
1206 | } |
1207 | ||
1208 | /* | |
1209 | * Init memory size counter | |
1210 | * See kernel-ctl.h for explanation of this value | |
1211 | */ | |
6725fe19 | 1212 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
ba7f0ae5 | 1213 | elist = zmalloc(sizeof(struct lttng_event) * nbmem); |
3b870559 MD |
1214 | if (elist == NULL) { |
1215 | PERROR("alloc list events"); | |
1216 | count = -ENOMEM; | |
1217 | goto end; | |
1218 | } | |
2ef84c95 | 1219 | |
53efb85a | 1220 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 1221 | if (count >= nbmem) { |
3b870559 | 1222 | struct lttng_event *new_elist; |
53efb85a | 1223 | size_t new_nbmem; |
3b870559 | 1224 | |
53efb85a MD |
1225 | new_nbmem = nbmem << 1; |
1226 | DBG("Reallocating event list from %zu to %zu bytes", | |
1227 | nbmem, new_nbmem); | |
1228 | new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event)); | |
3b870559 | 1229 | if (new_elist == NULL) { |
df0f840b | 1230 | PERROR("realloc list events"); |
3b870559 MD |
1231 | free(event); |
1232 | free(elist); | |
61b73b12 MD |
1233 | count = -ENOMEM; |
1234 | goto end; | |
2ef84c95 | 1235 | } |
53efb85a MD |
1236 | /* Zero the new memory */ |
1237 | memset(new_elist + nbmem, 0, | |
1238 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
1239 | nbmem = new_nbmem; | |
3b870559 | 1240 | elist = new_elist; |
2ef84c95 | 1241 | } |
99497cd0 MD |
1242 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
1243 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 1244 | elist[count].enabled = -1; |
9f19cc17 | 1245 | count++; |
3b870559 | 1246 | free(event); |
2ef84c95 DG |
1247 | } |
1248 | ||
9f19cc17 | 1249 | *events = elist; |
ced2f820 | 1250 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 1251 | end: |
799e2c4f MD |
1252 | ret = fclose(fp); /* closes both fp and fd */ |
1253 | if (ret) { | |
1254 | PERROR("fclose"); | |
1255 | } | |
9f19cc17 | 1256 | return count; |
2ef84c95 | 1257 | |
61b73b12 | 1258 | error_fp: |
799e2c4f MD |
1259 | ret = close(fd); |
1260 | if (ret) { | |
1261 | PERROR("close"); | |
1262 | } | |
2ef84c95 DG |
1263 | error: |
1264 | return -1; | |
1265 | } | |
096102bd DG |
1266 | |
1267 | /* | |
1268 | * Get kernel version and validate it. | |
1269 | */ | |
7d268848 | 1270 | int kernel_validate_version(struct lttng_kernel_tracer_version *version, |
88076e89 | 1271 | struct lttng_kernel_tracer_abi_version *abi_version) |
096102bd DG |
1272 | { |
1273 | int ret; | |
096102bd | 1274 | |
7d268848 | 1275 | ret = kernctl_tracer_version(kernel_tracer_fd, version); |
096102bd | 1276 | if (ret < 0) { |
521dd134 | 1277 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
1278 | goto error; |
1279 | } | |
1280 | ||
1281 | /* Validate version */ | |
88076e89 | 1282 | if (version->major != VERSION_MAJOR) { |
c052142c | 1283 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", |
88076e89 | 1284 | version->major, VERSION_MAJOR); |
096102bd | 1285 | goto error_version; |
096102bd | 1286 | } |
7d268848 | 1287 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, abi_version); |
c052142c | 1288 | if (ret < 0) { |
521dd134 | 1289 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
1290 | goto error; |
1291 | } | |
88076e89 | 1292 | if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) { |
521dd134 | 1293 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
88076e89 | 1294 | abi_version->major, abi_version->minor, |
c052142c MD |
1295 | LTTNG_MODULES_ABI_MAJOR_VERSION); |
1296 | goto error; | |
1297 | } | |
1298 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
88076e89 JD |
1299 | version->major, version->minor, |
1300 | abi_version->major, abi_version->minor); | |
096102bd DG |
1301 | return 0; |
1302 | ||
1303 | error_version: | |
096102bd DG |
1304 | ret = -1; |
1305 | ||
1306 | error: | |
521dd134 | 1307 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
1308 | return ret; |
1309 | } | |
335a95b7 MD |
1310 | |
1311 | /* | |
1312 | * Kernel work-arounds called at the start of sessiond main(). | |
1313 | */ | |
1314 | int init_kernel_workarounds(void) | |
1315 | { | |
8936c33a | 1316 | int ret; |
335a95b7 MD |
1317 | FILE *fp; |
1318 | ||
1319 | /* | |
1320 | * boot_id needs to be read once before being used concurrently | |
1321 | * to deal with a Linux kernel race. A fix is proposed for | |
1322 | * upstream, but the work-around is needed for older kernels. | |
1323 | */ | |
1324 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
1325 | if (!fp) { | |
1326 | goto end_boot_id; | |
1327 | } | |
1328 | while (!feof(fp)) { | |
1329 | char buf[37] = ""; | |
1330 | ||
8936c33a DG |
1331 | ret = fread(buf, 1, sizeof(buf), fp); |
1332 | if (ret < 0) { | |
1333 | /* Ignore error, we don't really care */ | |
1334 | } | |
335a95b7 | 1335 | } |
799e2c4f MD |
1336 | ret = fclose(fp); |
1337 | if (ret) { | |
1338 | PERROR("fclose"); | |
1339 | } | |
335a95b7 | 1340 | end_boot_id: |
335a95b7 MD |
1341 | return 0; |
1342 | } | |
2f77fc4b DG |
1343 | |
1344 | /* | |
d070c424 | 1345 | * Teardown of a kernel session, keeping data required by destroy notifiers. |
2f77fc4b DG |
1346 | */ |
1347 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
1348 | { | |
82b69413 JG |
1349 | struct lttng_trace_chunk *trace_chunk; |
1350 | ||
2f77fc4b DG |
1351 | if (ksess == NULL) { |
1352 | DBG3("No kernel session when tearing down session"); | |
1353 | return; | |
1354 | } | |
1355 | ||
1356 | DBG("Tearing down kernel session"); | |
82b69413 | 1357 | trace_chunk = ksess->current_trace_chunk; |
2f77fc4b | 1358 | |
07b86b52 | 1359 | /* |
15dc512a DG |
1360 | * Destroy channels on the consumer if at least one FD has been sent and we |
1361 | * are in no output mode because the streams are in *no* monitor mode so we | |
1362 | * have to send a command to clean them up or else they leaked. | |
07b86b52 | 1363 | */ |
15dc512a | 1364 | if (!ksess->output_traces && ksess->consumer_fds_sent) { |
07b86b52 JD |
1365 | int ret; |
1366 | struct consumer_socket *socket; | |
1367 | struct lttng_ht_iter iter; | |
1368 | ||
1369 | /* For each consumer socket. */ | |
d069d577 | 1370 | rcu_read_lock(); |
07b86b52 JD |
1371 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, |
1372 | socket, node.node) { | |
1373 | struct ltt_kernel_channel *chan; | |
1374 | ||
1375 | /* For each channel, ask the consumer to destroy it. */ | |
1376 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1377 | ret = kernel_consumer_destroy_channel(socket, chan); | |
1378 | if (ret < 0) { | |
1379 | /* Consumer is probably dead. Use next socket. */ | |
1380 | continue; | |
1381 | } | |
1382 | } | |
1383 | } | |
d069d577 | 1384 | rcu_read_unlock(); |
07b86b52 JD |
1385 | } |
1386 | ||
2f77fc4b DG |
1387 | /* Close any relayd session */ |
1388 | consumer_output_send_destroy_relayd(ksess->consumer); | |
1389 | ||
1390 | trace_kernel_destroy_session(ksess); | |
82b69413 | 1391 | lttng_trace_chunk_put(trace_chunk); |
2f77fc4b | 1392 | } |
fb5f35b6 | 1393 | |
d070c424 MD |
1394 | /* Teardown of data required by destroy notifiers. */ |
1395 | void kernel_free_session(struct ltt_kernel_session *ksess) | |
1396 | { | |
1397 | if (ksess == NULL) { | |
1398 | return; | |
1399 | } | |
1400 | trace_kernel_free_session(ksess); | |
1401 | } | |
1402 | ||
fb5f35b6 DG |
1403 | /* |
1404 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
1405 | */ | |
1406 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
1407 | { | |
1408 | struct ltt_kernel_session *ksess = NULL; | |
1409 | ||
1410 | assert(kchan); | |
1411 | assert(kchan->channel); | |
1412 | ||
1413 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
1414 | ||
1415 | /* Update channel count of associated session. */ | |
1416 | if (kchan->session) { | |
1417 | /* Keep pointer reference so we can update it after the destroy. */ | |
1418 | ksess = kchan->session; | |
1419 | } | |
1420 | ||
1421 | trace_kernel_destroy_channel(kchan); | |
1422 | ||
1423 | /* | |
1424 | * At this point the kernel channel is not visible anymore. This is safe | |
1425 | * since in order to work on a visible kernel session, the tracing session | |
1426 | * lock (ltt_session.lock) MUST be acquired. | |
1427 | */ | |
1428 | if (ksess) { | |
1429 | ksess->channel_count--; | |
1430 | } | |
1431 | } | |
6dc3064a DG |
1432 | |
1433 | /* | |
1434 | * Take a snapshot for a given kernel session. | |
1435 | * | |
9a654598 | 1436 | * Return LTTNG_OK on success or else return a LTTNG_ERR code. |
6dc3064a | 1437 | */ |
fb9a95c4 JG |
1438 | enum lttng_error_code kernel_snapshot_record( |
1439 | struct ltt_kernel_session *ksess, | |
348a81dc | 1440 | const struct consumer_output *output, int wait, |
d07ceecd | 1441 | uint64_t nb_packets_per_stream) |
6dc3064a | 1442 | { |
2a06df8d | 1443 | int err, ret, saved_metadata_fd; |
9a654598 | 1444 | enum lttng_error_code status = LTTNG_OK; |
6dc3064a DG |
1445 | struct consumer_socket *socket; |
1446 | struct lttng_ht_iter iter; | |
1447 | struct ltt_kernel_metadata *saved_metadata; | |
3b967712 | 1448 | char *trace_path = NULL; |
5da88b0f | 1449 | size_t consumer_path_offset = 0; |
6dc3064a DG |
1450 | |
1451 | assert(ksess); | |
1452 | assert(ksess->consumer); | |
1453 | assert(output); | |
1454 | ||
1455 | DBG("Kernel snapshot record started"); | |
1456 | ||
1457 | /* Save current metadata since the following calls will change it. */ | |
1458 | saved_metadata = ksess->metadata; | |
1459 | saved_metadata_fd = ksess->metadata_stream_fd; | |
1460 | ||
1461 | rcu_read_lock(); | |
1462 | ||
1463 | ret = kernel_open_metadata(ksess); | |
1464 | if (ret < 0) { | |
9a654598 | 1465 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1466 | goto error; |
1467 | } | |
1468 | ||
1469 | ret = kernel_open_metadata_stream(ksess); | |
1470 | if (ret < 0) { | |
9a654598 | 1471 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1472 | goto error_open_stream; |
1473 | } | |
1474 | ||
3b967712 | 1475 | trace_path = setup_channel_trace_path(ksess->consumer, |
5da88b0f | 1476 | DEFAULT_KERNEL_TRACE_DIR, &consumer_path_offset); |
3b967712 MD |
1477 | if (!trace_path) { |
1478 | status = LTTNG_ERR_INVALID; | |
1479 | goto error; | |
1480 | } | |
6dc3064a | 1481 | /* Send metadata to consumer and snapshot everything. */ |
348a81dc | 1482 | cds_lfht_for_each_entry(output->socks->ht, &iter.iter, |
6dc3064a | 1483 | socket, node.node) { |
6dc3064a | 1484 | struct ltt_kernel_channel *chan; |
6dc3064a | 1485 | |
6dc3064a DG |
1486 | pthread_mutex_lock(socket->lock); |
1487 | /* This stream must not be monitored by the consumer. */ | |
07b86b52 | 1488 | ret = kernel_consumer_add_metadata(socket, ksess, 0); |
6dc3064a | 1489 | pthread_mutex_unlock(socket->lock); |
6dc3064a | 1490 | if (ret < 0) { |
0ed78e50 | 1491 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1492 | goto error_consumer; |
1493 | } | |
1494 | ||
1495 | /* For each channel, ask the consumer to snapshot it. */ | |
1496 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
9a654598 | 1497 | status = consumer_snapshot_channel(socket, chan->key, output, 0, |
5c786ded | 1498 | ksess->uid, ksess->gid, |
5da88b0f | 1499 | &trace_path[consumer_path_offset], wait, |
d2956687 | 1500 | nb_packets_per_stream); |
9a654598 | 1501 | if (status != LTTNG_OK) { |
2a06df8d DG |
1502 | (void) kernel_consumer_destroy_metadata(socket, |
1503 | ksess->metadata); | |
6dc3064a DG |
1504 | goto error_consumer; |
1505 | } | |
1506 | } | |
1507 | ||
1508 | /* Snapshot metadata, */ | |
9a654598 | 1509 | status = consumer_snapshot_channel(socket, ksess->metadata->key, output, |
5da88b0f MD |
1510 | 1, ksess->uid, ksess->gid, &trace_path[consumer_path_offset], |
1511 | wait, 0); | |
9a654598 | 1512 | if (status != LTTNG_OK) { |
6dc3064a DG |
1513 | goto error_consumer; |
1514 | } | |
07b86b52 JD |
1515 | |
1516 | /* | |
1517 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1518 | * it's not monitored on the consumer side. | |
1519 | */ | |
1520 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1521 | } |
1522 | ||
1523 | error_consumer: | |
1524 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1525 | err = close(ksess->metadata_stream_fd); |
1526 | if (err < 0) { | |
6dc3064a DG |
1527 | PERROR("close snapshot kernel"); |
1528 | } | |
1529 | ||
1530 | error_open_stream: | |
1531 | trace_kernel_destroy_metadata(ksess->metadata); | |
1532 | error: | |
1533 | /* Restore metadata state.*/ | |
1534 | ksess->metadata = saved_metadata; | |
1535 | ksess->metadata_stream_fd = saved_metadata_fd; | |
6dc3064a | 1536 | rcu_read_unlock(); |
3b967712 | 1537 | free(trace_path); |
9a654598 | 1538 | return status; |
6dc3064a | 1539 | } |
834978fd DG |
1540 | |
1541 | /* | |
1542 | * Get the syscall mask array from the kernel tracer. | |
1543 | * | |
1544 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1545 | * be freed. | |
1546 | */ | |
1547 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1548 | { | |
1549 | assert(syscall_mask); | |
1550 | assert(nr_bits); | |
1551 | ||
1552 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1553 | } | |
6e21424e JR |
1554 | |
1555 | /* | |
1556 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1557 | * version number. | |
1558 | * | |
1559 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1560 | * of errors. | |
1561 | */ | |
7d268848 | 1562 | int kernel_supports_ring_buffer_snapshot_sample_positions(void) |
6e21424e JR |
1563 | { |
1564 | int ret = 0; // Not supported by default | |
1565 | struct lttng_kernel_tracer_abi_version abi; | |
1566 | ||
7d268848 | 1567 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, &abi); |
6e21424e JR |
1568 | if (ret < 0) { |
1569 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1570 | goto error; | |
1571 | } | |
1572 | ||
1573 | /* | |
1574 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1575 | */ | |
1576 | if (abi.major >= 2 && abi.minor >= 3) { | |
1577 | /* Supported */ | |
1578 | ret = 1; | |
1579 | } else { | |
1580 | /* Not supported */ | |
1581 | ret = 0; | |
1582 | } | |
1583 | error: | |
1584 | return ret; | |
1585 | } | |
5c408ad8 | 1586 | |
a40a503f MD |
1587 | /* |
1588 | * Check for the support of the packet sequence number via abi version number. | |
1589 | * | |
1590 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1591 | * of errors. | |
1592 | */ | |
1593 | int kernel_supports_ring_buffer_packet_sequence_number(void) | |
1594 | { | |
1595 | int ret = 0; // Not supported by default | |
1596 | struct lttng_kernel_tracer_abi_version abi; | |
1597 | ||
1598 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, &abi); | |
1599 | if (ret < 0) { | |
1600 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1601 | goto error; | |
1602 | } | |
1603 | ||
1604 | /* | |
3029bc92 JG |
1605 | * Packet sequence number was introduced in LTTng 2.8, |
1606 | * lttng-modules ABI 2.1. | |
a40a503f | 1607 | */ |
3029bc92 | 1608 | if (abi.major >= 2 && abi.minor >= 1) { |
a40a503f MD |
1609 | /* Supported */ |
1610 | ret = 1; | |
1611 | } else { | |
1612 | /* Not supported */ | |
1613 | ret = 0; | |
1614 | } | |
1615 | error: | |
1616 | return ret; | |
1617 | } | |
1618 | ||
5c408ad8 JD |
1619 | /* |
1620 | * Rotate a kernel session. | |
1621 | * | |
d5a1b7aa | 1622 | * Return LTTNG_OK on success or else an LTTng error code. |
5c408ad8 | 1623 | */ |
d5a1b7aa | 1624 | enum lttng_error_code kernel_rotate_session(struct ltt_session *session) |
5c408ad8 JD |
1625 | { |
1626 | int ret; | |
d5a1b7aa | 1627 | enum lttng_error_code status = LTTNG_OK; |
5c408ad8 JD |
1628 | struct consumer_socket *socket; |
1629 | struct lttng_ht_iter iter; | |
1630 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1631 | ||
1632 | assert(ksess); | |
1633 | assert(ksess->consumer); | |
1634 | ||
1635 | DBG("Rotate kernel session %s started (session %" PRIu64 ")", | |
1636 | session->name, session->id); | |
1637 | ||
1638 | rcu_read_lock(); | |
1639 | ||
1640 | /* | |
1641 | * Note that this loop will end after one iteration given that there is | |
1642 | * only one kernel consumer. | |
1643 | */ | |
1644 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1645 | socket, node.node) { | |
1646 | struct ltt_kernel_channel *chan; | |
1647 | ||
d2956687 | 1648 | /* For each channel, ask the consumer to rotate it. */ |
5c408ad8 | 1649 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { |
92816cc3 JG |
1650 | DBG("Rotate kernel channel %" PRIu64 ", session %s", |
1651 | chan->key, session->name); | |
5c408ad8 JD |
1652 | ret = consumer_rotate_channel(socket, chan->key, |
1653 | ksess->uid, ksess->gid, ksess->consumer, | |
d2956687 | 1654 | /* is_metadata_channel */ false); |
5c408ad8 | 1655 | if (ret < 0) { |
d5a1b7aa | 1656 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1657 | goto error; |
1658 | } | |
1659 | } | |
1660 | ||
1661 | /* | |
1662 | * Rotate the metadata channel. | |
1663 | */ | |
22a1b931 | 1664 | ret = consumer_rotate_channel(socket, ksess->metadata->key, |
5c408ad8 | 1665 | ksess->uid, ksess->gid, ksess->consumer, |
d2956687 | 1666 | /* is_metadata_channel */ true); |
5c408ad8 | 1667 | if (ret < 0) { |
d5a1b7aa | 1668 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1669 | goto error; |
1670 | } | |
1671 | } | |
1672 | ||
5c408ad8 JD |
1673 | error: |
1674 | rcu_read_unlock(); | |
d5a1b7aa | 1675 | return status; |
5c408ad8 | 1676 | } |
d2956687 JG |
1677 | |
1678 | enum lttng_error_code kernel_create_channel_subdirectories( | |
1679 | const struct ltt_kernel_session *ksess) | |
1680 | { | |
1681 | enum lttng_error_code ret = LTTNG_OK; | |
1682 | enum lttng_trace_chunk_status chunk_status; | |
1683 | ||
1684 | rcu_read_lock(); | |
1685 | assert(ksess->current_trace_chunk); | |
1686 | ||
1687 | /* | |
1688 | * Create the index subdirectory which will take care | |
1689 | * of implicitly creating the channel's path. | |
1690 | */ | |
1691 | chunk_status = lttng_trace_chunk_create_subdirectory( | |
1692 | ksess->current_trace_chunk, | |
1693 | DEFAULT_KERNEL_TRACE_DIR "/" DEFAULT_INDEX_DIR); | |
1694 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { | |
1695 | ret = LTTNG_ERR_CREATE_DIR_FAIL; | |
1696 | goto error; | |
1697 | } | |
1698 | error: | |
1699 | rcu_read_unlock(); | |
1700 | return ret; | |
1701 | } | |
7d268848 MD |
1702 | |
1703 | /* | |
1704 | * Setup necessary data for kernel tracer action. | |
1705 | */ | |
1706 | LTTNG_HIDDEN | |
1707 | int init_kernel_tracer(void) | |
1708 | { | |
1709 | int ret; | |
1710 | bool is_root = !getuid(); | |
1711 | ||
1712 | /* Modprobe lttng kernel modules */ | |
1713 | ret = modprobe_lttng_control(); | |
1714 | if (ret < 0) { | |
1715 | goto error; | |
1716 | } | |
1717 | ||
1718 | /* Open debugfs lttng */ | |
1719 | kernel_tracer_fd = open(module_proc_lttng, O_RDWR); | |
1720 | if (kernel_tracer_fd < 0) { | |
1721 | DBG("Failed to open %s", module_proc_lttng); | |
1722 | goto error_open; | |
1723 | } | |
1724 | ||
1725 | /* Validate kernel version */ | |
1726 | ret = kernel_validate_version(&kernel_tracer_version, | |
1727 | &kernel_tracer_abi_version); | |
1728 | if (ret < 0) { | |
1729 | goto error_version; | |
1730 | } | |
1731 | ||
1732 | ret = modprobe_lttng_data(); | |
1733 | if (ret < 0) { | |
1734 | goto error_modules; | |
1735 | } | |
1736 | ||
1737 | ret = kernel_supports_ring_buffer_snapshot_sample_positions(); | |
1738 | if (ret < 0) { | |
1739 | goto error_modules; | |
1740 | } | |
1741 | ||
1742 | if (ret < 1) { | |
1743 | WARN("Kernel tracer does not support buffer monitoring. " | |
1744 | "The monitoring timer of channels in the kernel domain " | |
1745 | "will be set to 0 (disabled)."); | |
1746 | } | |
1747 | ||
1748 | DBG("Kernel tracer fd %d", kernel_tracer_fd); | |
1749 | ||
1750 | ret = syscall_init_table(kernel_tracer_fd); | |
1751 | if (ret < 0) { | |
1752 | ERR("Unable to populate syscall table. Syscall tracing won't " | |
1753 | "work for this session daemon."); | |
1754 | } | |
1755 | return 0; | |
1756 | ||
1757 | error_version: | |
1758 | modprobe_remove_lttng_control(); | |
1759 | ret = close(kernel_tracer_fd); | |
1760 | if (ret) { | |
1761 | PERROR("close"); | |
1762 | } | |
1763 | kernel_tracer_fd = -1; | |
1764 | return LTTNG_ERR_KERN_VERSION; | |
1765 | ||
1766 | error_modules: | |
1767 | ret = close(kernel_tracer_fd); | |
1768 | if (ret) { | |
1769 | PERROR("close"); | |
1770 | } | |
1771 | ||
1772 | error_open: | |
1773 | modprobe_remove_lttng_control(); | |
1774 | ||
1775 | error: | |
1776 | WARN("No kernel tracer available"); | |
1777 | kernel_tracer_fd = -1; | |
1778 | if (!is_root) { | |
1779 | return LTTNG_ERR_NEED_ROOT_SESSIOND; | |
1780 | } else { | |
1781 | return LTTNG_ERR_KERN_NA; | |
1782 | } | |
1783 | } | |
1784 | ||
1785 | LTTNG_HIDDEN | |
1786 | void cleanup_kernel_tracer(void) | |
1787 | { | |
1788 | int ret; | |
1789 | ||
1790 | DBG2("Closing kernel fd"); | |
1791 | if (kernel_tracer_fd >= 0) { | |
1792 | ret = close(kernel_tracer_fd); | |
1793 | if (ret) { | |
1794 | PERROR("close"); | |
1795 | } | |
1796 | kernel_tracer_fd = -1; | |
1797 | } | |
1798 | DBG("Unloading kernel modules"); | |
1799 | modprobe_remove_lttng_all(); | |
1800 | free(syscall_table); | |
1801 | } | |
1802 | ||
1803 | LTTNG_HIDDEN | |
1804 | bool kernel_tracer_is_initialized(void) | |
1805 | { | |
1806 | return kernel_tracer_fd >= 0; | |
1807 | } | |
bca212a2 MD |
1808 | |
1809 | /* | |
1810 | * Clear a kernel session. | |
1811 | * | |
1812 | * Return LTTNG_OK on success or else an LTTng error code. | |
1813 | */ | |
1814 | enum lttng_error_code kernel_clear_session(struct ltt_session *session) | |
1815 | { | |
1816 | int ret; | |
1817 | enum lttng_error_code status = LTTNG_OK; | |
1818 | struct consumer_socket *socket; | |
1819 | struct lttng_ht_iter iter; | |
1820 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1821 | ||
1822 | assert(ksess); | |
1823 | assert(ksess->consumer); | |
1824 | ||
1825 | DBG("Clear kernel session %s (session %" PRIu64 ")", | |
1826 | session->name, session->id); | |
1827 | ||
1828 | rcu_read_lock(); | |
1829 | ||
1830 | if (ksess->active) { | |
1831 | ERR("Expecting inactive session %s (%" PRIu64 ")", session->name, session->id); | |
1832 | status = LTTNG_ERR_FATAL; | |
1833 | goto end; | |
1834 | } | |
1835 | ||
1836 | /* | |
1837 | * Note that this loop will end after one iteration given that there is | |
1838 | * only one kernel consumer. | |
1839 | */ | |
1840 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1841 | socket, node.node) { | |
1842 | struct ltt_kernel_channel *chan; | |
1843 | ||
1844 | /* For each channel, ask the consumer to clear it. */ | |
1845 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1846 | DBG("Clear kernel channel %" PRIu64 ", session %s", | |
1847 | chan->key, session->name); | |
1848 | ret = consumer_clear_channel(socket, chan->key); | |
1849 | if (ret < 0) { | |
1850 | goto error; | |
1851 | } | |
1852 | } | |
1853 | ||
1854 | if (!ksess->metadata) { | |
1855 | /* | |
1856 | * Nothing to do for the metadata. | |
1857 | * This is a snapshot session. | |
1858 | * The metadata is genererated on the fly. | |
1859 | */ | |
1860 | continue; | |
1861 | } | |
1862 | ||
1863 | /* | |
1864 | * Clear the metadata channel. | |
1865 | * Metadata channel is not cleared per se but we still need to | |
1866 | * perform a rotation operation on it behind the scene. | |
1867 | */ | |
1868 | ret = consumer_clear_channel(socket, ksess->metadata->key); | |
1869 | if (ret < 0) { | |
1870 | goto error; | |
1871 | } | |
1872 | } | |
1873 | ||
1874 | goto end; | |
1875 | error: | |
1876 | switch (-ret) { | |
1877 | case LTTCOMM_CONSUMERD_RELAYD_CLEAR_DISALLOWED: | |
1878 | status = LTTNG_ERR_CLEAR_RELAY_DISALLOWED; | |
1879 | break; | |
1880 | default: | |
1881 | status = LTTNG_ERR_CLEAR_FAIL_CONSUMER; | |
1882 | break; | |
1883 | } | |
1884 | end: | |
1885 | rcu_read_unlock(); | |
1886 | return status; | |
1887 | } |