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; | |
a7a533cd | 710 | struct lttng_tracker_ids *saved_ids; |
7c493d31 | 711 | |
55c9e7ca JR |
712 | ret = lttng_tracker_id_lookup_string(tracker_type, id, &value); |
713 | if (ret != LTTNG_OK) { | |
714 | return ret; | |
7c493d31 | 715 | } |
55c9e7ca JR |
716 | |
717 | tracker_list = get_id_tracker_list(session, tracker_type); | |
718 | if (!tracker_list) { | |
7c493d31 | 719 | return LTTNG_ERR_INVALID; |
7c493d31 | 720 | } |
ccf10263 | 721 | |
55c9e7ca | 722 | /* Save list for restore on error. */ |
a7a533cd JR |
723 | ret = lttng_tracker_id_get_list(tracker_list, &saved_ids); |
724 | if (ret != LTTNG_OK) { | |
55c9e7ca JR |
725 | return LTTNG_ERR_INVALID; |
726 | } | |
7c493d31 | 727 | |
55c9e7ca JR |
728 | /* Add to list. */ |
729 | ret = lttng_tracker_list_add(tracker_list, id); | |
730 | if (ret != LTTNG_OK) { | |
731 | goto end; | |
7c493d31 | 732 | } |
55c9e7ca JR |
733 | |
734 | switch (tracker_type) { | |
735 | case LTTNG_TRACKER_PID: | |
736 | DBG("Kernel track PID %d for session id %" PRIu64 ".", value, | |
737 | session->id); | |
738 | ret = kernctl_track_pid(session->fd, value); | |
739 | if (!ret) { | |
740 | ret = LTTNG_OK; | |
741 | goto end; | |
742 | } | |
743 | break; | |
744 | case LTTNG_TRACKER_VPID: | |
745 | DBG("Kernel track VPID %d for session id %" PRIu64 ".", value, | |
746 | session->id); | |
747 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_VPID, value); | |
748 | if (!ret) { | |
749 | ret = LTTNG_OK; | |
750 | goto end; | |
751 | } | |
752 | break; | |
753 | case LTTNG_TRACKER_UID: | |
754 | DBG("Kernel track UID %d for session id %" PRIu64 ".", value, | |
755 | session->id); | |
756 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_UID, value); | |
757 | if (!ret) { | |
758 | ret = LTTNG_OK; | |
759 | goto end; | |
760 | } | |
761 | break; | |
762 | case LTTNG_TRACKER_GID: | |
763 | DBG("Kernel track GID %d for session id %" PRIu64 ".", value, | |
764 | session->id); | |
765 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_GID, value); | |
766 | if (!ret) { | |
767 | ret = LTTNG_OK; | |
768 | goto end; | |
769 | } | |
770 | break; | |
771 | case LTTNG_TRACKER_VUID: | |
772 | DBG("Kernel track VUID %d for session id %" PRIu64 ".", value, | |
773 | session->id); | |
774 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_VUID, value); | |
775 | if (!ret) { | |
776 | ret = LTTNG_OK; | |
777 | goto end; | |
778 | } | |
779 | break; | |
780 | case LTTNG_TRACKER_VGID: | |
781 | DBG("Kernel track VGID %d for session id %" PRIu64 ".", value, | |
782 | session->id); | |
783 | ret = kernctl_track_id(session->fd, LTTNG_TRACKER_VGID, value); | |
784 | if (!ret) { | |
785 | ret = LTTNG_OK; | |
786 | goto end; | |
787 | } | |
788 | break; | |
789 | default: | |
790 | ret = -EINVAL; | |
791 | break; | |
792 | } | |
793 | ||
794 | /* Error handling. */ | |
32af2c95 | 795 | switch (-ret) { |
7c493d31 | 796 | case EINVAL: |
55c9e7ca JR |
797 | ret = LTTNG_ERR_INVALID; |
798 | break; | |
7c493d31 | 799 | case ENOMEM: |
55c9e7ca JR |
800 | ret = LTTNG_ERR_NOMEM; |
801 | break; | |
802 | case EEXIST: | |
803 | ret = LTTNG_ERR_ID_TRACKED; | |
804 | break; | |
7c493d31 | 805 | default: |
55c9e7ca JR |
806 | ret = LTTNG_ERR_UNK; |
807 | break; | |
808 | } | |
809 | ||
a7a533cd | 810 | if (lttng_tracker_id_set_list(tracker_list, saved_ids) != LTTNG_OK) { |
55c9e7ca | 811 | ERR("Error on tracker add error handling.\n"); |
7c493d31 | 812 | } |
55c9e7ca | 813 | end: |
a7a533cd | 814 | lttng_tracker_ids_destroy(saved_ids); |
55c9e7ca | 815 | return ret; |
ccf10263 MD |
816 | } |
817 | ||
55c9e7ca JR |
818 | int kernel_untrack_id(enum lttng_tracker_type tracker_type, |
819 | struct ltt_kernel_session *session, | |
820 | const struct lttng_tracker_id *id) | |
a5dfbb9d | 821 | { |
55c9e7ca JR |
822 | int ret, value; |
823 | struct lttng_tracker_list *tracker_list; | |
a7a533cd | 824 | struct lttng_tracker_ids *saved_ids; |
a5dfbb9d | 825 | |
55c9e7ca JR |
826 | ret = lttng_tracker_id_lookup_string(tracker_type, id, &value); |
827 | if (ret != LTTNG_OK) { | |
828 | return ret; | |
a5dfbb9d MD |
829 | } |
830 | ||
55c9e7ca JR |
831 | tracker_list = get_id_tracker_list(session, tracker_type); |
832 | if (!tracker_list) { | |
833 | return LTTNG_ERR_INVALID; | |
a5dfbb9d | 834 | } |
55c9e7ca | 835 | /* Save list for restore on error. */ |
a7a533cd JR |
836 | ret = lttng_tracker_id_get_list(tracker_list, &saved_ids); |
837 | if (ret != LTTNG_OK) { | |
55c9e7ca JR |
838 | return LTTNG_ERR_INVALID; |
839 | } | |
840 | /* Remove from list. */ | |
841 | ret = lttng_tracker_list_remove(tracker_list, id); | |
842 | if (ret != LTTNG_OK) { | |
a5dfbb9d MD |
843 | goto end; |
844 | } | |
845 | ||
55c9e7ca JR |
846 | switch (tracker_type) { |
847 | case LTTNG_TRACKER_PID: | |
848 | DBG("Kernel untrack PID %d for session id %" PRIu64 ".", value, | |
849 | session->id); | |
850 | ret = kernctl_untrack_pid(session->fd, value); | |
851 | if (!ret) { | |
852 | ret = LTTNG_OK; | |
853 | goto end; | |
854 | } | |
855 | break; | |
856 | case LTTNG_TRACKER_VPID: | |
857 | DBG("Kernel untrack VPID %d for session id %" PRIu64 ".", value, | |
858 | session->id); | |
859 | ret = kernctl_untrack_id( | |
860 | session->fd, LTTNG_TRACKER_VPID, value); | |
861 | if (!ret) { | |
862 | ret = LTTNG_OK; | |
863 | goto end; | |
864 | } | |
865 | break; | |
866 | case LTTNG_TRACKER_UID: | |
867 | DBG("Kernel untrack UID %d for session id %" PRIu64 ".", value, | |
868 | session->id); | |
869 | ret = kernctl_untrack_id(session->fd, LTTNG_TRACKER_UID, value); | |
870 | if (!ret) { | |
871 | ret = LTTNG_OK; | |
872 | goto end; | |
873 | } | |
874 | break; | |
875 | case LTTNG_TRACKER_GID: | |
876 | DBG("Kernel untrack GID %d for session id %" PRIu64 ".", value, | |
877 | session->id); | |
878 | ret = kernctl_untrack_id(session->fd, LTTNG_TRACKER_GID, value); | |
879 | if (!ret) { | |
880 | ret = LTTNG_OK; | |
881 | goto end; | |
882 | } | |
883 | break; | |
884 | case LTTNG_TRACKER_VUID: | |
885 | DBG("Kernel untrack VUID %d for session id %" PRIu64 ".", value, | |
886 | session->id); | |
887 | ret = kernctl_untrack_id( | |
888 | session->fd, LTTNG_TRACKER_VUID, value); | |
889 | if (!ret) { | |
890 | ret = LTTNG_OK; | |
891 | goto end; | |
892 | } | |
893 | break; | |
894 | case LTTNG_TRACKER_VGID: | |
895 | DBG("Kernel untrack VGID %d for session id %" PRIu64 ".", value, | |
896 | session->id); | |
897 | ret = kernctl_untrack_id( | |
898 | session->fd, LTTNG_TRACKER_VGID, value); | |
899 | if (!ret) { | |
900 | ret = LTTNG_OK; | |
901 | goto end; | |
a5dfbb9d | 902 | } |
55c9e7ca JR |
903 | break; |
904 | default: | |
905 | ret = -EINVAL; | |
906 | break; | |
907 | } | |
908 | ||
909 | /* Error handling. */ | |
910 | switch (-ret) { | |
911 | case EINVAL: | |
912 | ret = LTTNG_ERR_INVALID; | |
913 | break; | |
914 | case ENOMEM: | |
915 | ret = LTTNG_ERR_NOMEM; | |
916 | break; | |
917 | case EEXIST: | |
918 | ret = LTTNG_ERR_ID_TRACKED; | |
919 | break; | |
920 | default: | |
921 | ret = LTTNG_ERR_UNK; | |
922 | break; | |
a5dfbb9d MD |
923 | } |
924 | ||
a7a533cd | 925 | if (lttng_tracker_id_set_list(tracker_list, saved_ids) != LTTNG_OK) { |
55c9e7ca JR |
926 | ERR("Error on tracker remove error handling.\n"); |
927 | } | |
a5dfbb9d | 928 | end: |
a7a533cd | 929 | lttng_tracker_ids_destroy(saved_ids); |
55c9e7ca JR |
930 | return ret; |
931 | } | |
a5dfbb9d | 932 | |
55c9e7ca JR |
933 | /* |
934 | * Called with session lock held. | |
935 | */ | |
a7a533cd | 936 | int kernel_list_tracker_ids(enum lttng_tracker_type tracker_type, |
55c9e7ca | 937 | struct ltt_kernel_session *session, |
a7a533cd | 938 | struct lttng_tracker_ids **_ids) |
55c9e7ca | 939 | { |
a7a533cd | 940 | int ret = 0; |
55c9e7ca JR |
941 | struct lttng_tracker_list *tracker_list; |
942 | ||
943 | tracker_list = get_id_tracker_list(session, tracker_type); | |
944 | if (!tracker_list) { | |
a7a533cd JR |
945 | ret = -LTTNG_ERR_INVALID; |
946 | goto end; | |
a5dfbb9d | 947 | } |
a7a533cd JR |
948 | |
949 | ret = lttng_tracker_id_get_list(tracker_list, _ids); | |
950 | if (ret != LTTNG_OK) { | |
951 | ret = -LTTNG_ERR_INVALID; | |
952 | goto end; | |
953 | } | |
954 | ||
955 | end: | |
956 | return ret; | |
a5dfbb9d MD |
957 | } |
958 | ||
aaf26714 | 959 | /* |
050349bb DG |
960 | * Create kernel metadata, open from the kernel tracer and add it to the |
961 | * kernel session. | |
aaf26714 | 962 | */ |
a4b92340 | 963 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
964 | { |
965 | int ret; | |
74024a21 | 966 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 967 | |
0525e9ae DG |
968 | assert(session); |
969 | ||
54012638 | 970 | /* Allocate kernel metadata */ |
a4b92340 | 971 | lkm = trace_kernel_create_metadata(); |
54012638 | 972 | if (lkm == NULL) { |
aaf26714 DG |
973 | goto error; |
974 | } | |
975 | ||
54012638 | 976 | /* Kernel tracer metadata creation */ |
f3ed775e | 977 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 978 | if (ret < 0) { |
74024a21 | 979 | goto error_open; |
aaf26714 DG |
980 | } |
981 | ||
8c0faa1d | 982 | lkm->fd = ret; |
d40f0359 | 983 | lkm->key = ++next_kernel_channel_key; |
7b395890 DG |
984 | /* Prevent fd duplication after execlp() */ |
985 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
986 | if (ret < 0) { | |
df0f840b | 987 | PERROR("fcntl session fd"); |
7b395890 DG |
988 | } |
989 | ||
aaf26714 | 990 | session->metadata = lkm; |
8c0faa1d | 991 | |
00e2e675 | 992 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
993 | |
994 | return 0; | |
995 | ||
74024a21 DG |
996 | error_open: |
997 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 998 | error: |
54012638 | 999 | return -1; |
8c0faa1d DG |
1000 | } |
1001 | ||
1002 | /* | |
050349bb | 1003 | * Start tracing session. |
8c0faa1d DG |
1004 | */ |
1005 | int kernel_start_session(struct ltt_kernel_session *session) | |
1006 | { | |
1007 | int ret; | |
1008 | ||
0525e9ae DG |
1009 | assert(session); |
1010 | ||
8c0faa1d DG |
1011 | ret = kernctl_start_session(session->fd); |
1012 | if (ret < 0) { | |
df0f840b | 1013 | PERROR("ioctl start session"); |
8c0faa1d DG |
1014 | goto error; |
1015 | } | |
1016 | ||
1017 | DBG("Kernel session started"); | |
1018 | ||
1019 | return 0; | |
1020 | ||
1021 | error: | |
1022 | return ret; | |
1023 | } | |
1024 | ||
f3ed775e | 1025 | /* |
050349bb | 1026 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e | 1027 | */ |
7d268848 | 1028 | void kernel_wait_quiescent(void) |
f3ed775e DG |
1029 | { |
1030 | int ret; | |
7d268848 | 1031 | int fd = kernel_tracer_fd; |
f3ed775e DG |
1032 | |
1033 | DBG("Kernel quiescent wait on %d", fd); | |
1034 | ||
1035 | ret = kernctl_wait_quiescent(fd); | |
1036 | if (ret < 0) { | |
df0f840b | 1037 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
1038 | ERR("Kernel quiescent wait failed"); |
1039 | } | |
1040 | } | |
1041 | ||
1042 | /* | |
f3ed775e DG |
1043 | * Force flush buffer of metadata. |
1044 | */ | |
1045 | int kernel_metadata_flush_buffer(int fd) | |
1046 | { | |
1047 | int ret; | |
1048 | ||
169d2cb7 DG |
1049 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
1050 | ||
f3ed775e DG |
1051 | ret = kernctl_buffer_flush(fd); |
1052 | if (ret < 0) { | |
00e2e675 | 1053 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
1054 | } |
1055 | ||
1056 | return 0; | |
1057 | } | |
1058 | ||
1059 | /* | |
050349bb | 1060 | * Force flush buffer for channel. |
f3ed775e DG |
1061 | */ |
1062 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
1063 | { | |
1064 | int ret; | |
1065 | struct ltt_kernel_stream *stream; | |
1066 | ||
0525e9ae DG |
1067 | assert(channel); |
1068 | ||
f3ed775e DG |
1069 | DBG("Flush buffer for channel %s", channel->channel->name); |
1070 | ||
1071 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
1072 | DBG("Flushing channel stream %d", stream->fd); | |
1073 | ret = kernctl_buffer_flush(stream->fd); | |
1074 | if (ret < 0) { | |
df0f840b | 1075 | PERROR("ioctl"); |
f3ed775e DG |
1076 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
1077 | stream->fd, ret); | |
1078 | } | |
1079 | } | |
1080 | ||
1081 | return 0; | |
1082 | } | |
1083 | ||
8c0faa1d | 1084 | /* |
050349bb | 1085 | * Stop tracing session. |
8c0faa1d DG |
1086 | */ |
1087 | int kernel_stop_session(struct ltt_kernel_session *session) | |
1088 | { | |
1089 | int ret; | |
1090 | ||
0525e9ae DG |
1091 | assert(session); |
1092 | ||
8c0faa1d DG |
1093 | ret = kernctl_stop_session(session->fd); |
1094 | if (ret < 0) { | |
1095 | goto error; | |
1096 | } | |
1097 | ||
1098 | DBG("Kernel session stopped"); | |
1099 | ||
1100 | return 0; | |
1101 | ||
1102 | error: | |
1103 | return ret; | |
1104 | } | |
1105 | ||
1106 | /* | |
050349bb DG |
1107 | * Open stream of channel, register it to the kernel tracer and add it |
1108 | * to the stream list of the channel. | |
8c0faa1d | 1109 | * |
1cfb4b98 MD |
1110 | * Note: given that the streams may appear in random order wrt CPU |
1111 | * number (e.g. cpu hotplug), the index value of the stream number in | |
1112 | * the stream name is not necessarily linked to the CPU number. | |
1113 | * | |
050349bb | 1114 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 1115 | */ |
f3ed775e | 1116 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 1117 | { |
1cfb4b98 | 1118 | int ret; |
8c0faa1d DG |
1119 | struct ltt_kernel_stream *lks; |
1120 | ||
0525e9ae DG |
1121 | assert(channel); |
1122 | ||
5a47c6a2 | 1123 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
1124 | lks = trace_kernel_create_stream(channel->channel->name, |
1125 | channel->stream_count); | |
8c0faa1d | 1126 | if (lks == NULL) { |
799e2c4f MD |
1127 | ret = close(ret); |
1128 | if (ret) { | |
1129 | PERROR("close"); | |
1130 | } | |
8c0faa1d DG |
1131 | goto error; |
1132 | } | |
1133 | ||
1134 | lks->fd = ret; | |
7b395890 DG |
1135 | /* Prevent fd duplication after execlp() */ |
1136 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
1137 | if (ret < 0) { | |
df0f840b | 1138 | PERROR("fcntl session fd"); |
7b395890 DG |
1139 | } |
1140 | ||
1624d5b7 JD |
1141 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
1142 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
1143 | ||
1cfb4b98 | 1144 | /* Add stream to channel stream list */ |
8c0faa1d DG |
1145 | cds_list_add(&lks->list, &channel->stream_list.head); |
1146 | channel->stream_count++; | |
8c0faa1d | 1147 | |
00e2e675 DG |
1148 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
1149 | lks->state); | |
54012638 | 1150 | } |
8c0faa1d DG |
1151 | |
1152 | return channel->stream_count; | |
1153 | ||
1154 | error: | |
54012638 | 1155 | return -1; |
8c0faa1d DG |
1156 | } |
1157 | ||
1158 | /* | |
050349bb | 1159 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 1160 | */ |
f3ed775e | 1161 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
1162 | { |
1163 | int ret; | |
1164 | ||
0525e9ae DG |
1165 | assert(session); |
1166 | ||
8c0faa1d DG |
1167 | ret = kernctl_create_stream(session->metadata->fd); |
1168 | if (ret < 0) { | |
df0f840b | 1169 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
1170 | goto error; |
1171 | } | |
1172 | ||
1173 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
1174 | session->metadata_stream_fd = ret; | |
7b395890 DG |
1175 | /* Prevent fd duplication after execlp() */ |
1176 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
1177 | if (ret < 0) { | |
df0f840b | 1178 | PERROR("fcntl session fd"); |
7b395890 | 1179 | } |
aaf26714 DG |
1180 | |
1181 | return 0; | |
1182 | ||
1183 | error: | |
54012638 | 1184 | return -1; |
aaf26714 | 1185 | } |
2ef84c95 DG |
1186 | |
1187 | /* | |
9f19cc17 | 1188 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 1189 | */ |
7d268848 | 1190 | ssize_t kernel_list_events(struct lttng_event **events) |
2ef84c95 | 1191 | { |
53efb85a | 1192 | int fd, ret; |
9f19cc17 DG |
1193 | char *event; |
1194 | size_t nbmem, count = 0; | |
2ef84c95 | 1195 | FILE *fp; |
9f19cc17 | 1196 | struct lttng_event *elist; |
2ef84c95 | 1197 | |
0525e9ae DG |
1198 | assert(events); |
1199 | ||
7d268848 | 1200 | fd = kernctl_tracepoint_list(kernel_tracer_fd); |
2ef84c95 | 1201 | if (fd < 0) { |
df0f840b | 1202 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
1203 | goto error; |
1204 | } | |
1205 | ||
1206 | fp = fdopen(fd, "r"); | |
1207 | if (fp == NULL) { | |
df0f840b | 1208 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 1209 | goto error_fp; |
2ef84c95 DG |
1210 | } |
1211 | ||
1212 | /* | |
1213 | * Init memory size counter | |
1214 | * See kernel-ctl.h for explanation of this value | |
1215 | */ | |
6725fe19 | 1216 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
ba7f0ae5 | 1217 | elist = zmalloc(sizeof(struct lttng_event) * nbmem); |
3b870559 MD |
1218 | if (elist == NULL) { |
1219 | PERROR("alloc list events"); | |
1220 | count = -ENOMEM; | |
1221 | goto end; | |
1222 | } | |
2ef84c95 | 1223 | |
53efb85a | 1224 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 1225 | if (count >= nbmem) { |
3b870559 | 1226 | struct lttng_event *new_elist; |
53efb85a | 1227 | size_t new_nbmem; |
3b870559 | 1228 | |
53efb85a MD |
1229 | new_nbmem = nbmem << 1; |
1230 | DBG("Reallocating event list from %zu to %zu bytes", | |
1231 | nbmem, new_nbmem); | |
1232 | new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event)); | |
3b870559 | 1233 | if (new_elist == NULL) { |
df0f840b | 1234 | PERROR("realloc list events"); |
3b870559 MD |
1235 | free(event); |
1236 | free(elist); | |
61b73b12 MD |
1237 | count = -ENOMEM; |
1238 | goto end; | |
2ef84c95 | 1239 | } |
53efb85a MD |
1240 | /* Zero the new memory */ |
1241 | memset(new_elist + nbmem, 0, | |
1242 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
1243 | nbmem = new_nbmem; | |
3b870559 | 1244 | elist = new_elist; |
2ef84c95 | 1245 | } |
99497cd0 MD |
1246 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
1247 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 1248 | elist[count].enabled = -1; |
9f19cc17 | 1249 | count++; |
3b870559 | 1250 | free(event); |
2ef84c95 DG |
1251 | } |
1252 | ||
9f19cc17 | 1253 | *events = elist; |
ced2f820 | 1254 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 1255 | end: |
799e2c4f MD |
1256 | ret = fclose(fp); /* closes both fp and fd */ |
1257 | if (ret) { | |
1258 | PERROR("fclose"); | |
1259 | } | |
9f19cc17 | 1260 | return count; |
2ef84c95 | 1261 | |
61b73b12 | 1262 | error_fp: |
799e2c4f MD |
1263 | ret = close(fd); |
1264 | if (ret) { | |
1265 | PERROR("close"); | |
1266 | } | |
2ef84c95 DG |
1267 | error: |
1268 | return -1; | |
1269 | } | |
096102bd DG |
1270 | |
1271 | /* | |
1272 | * Get kernel version and validate it. | |
1273 | */ | |
7d268848 | 1274 | int kernel_validate_version(struct lttng_kernel_tracer_version *version, |
88076e89 | 1275 | struct lttng_kernel_tracer_abi_version *abi_version) |
096102bd DG |
1276 | { |
1277 | int ret; | |
096102bd | 1278 | |
7d268848 | 1279 | ret = kernctl_tracer_version(kernel_tracer_fd, version); |
096102bd | 1280 | if (ret < 0) { |
521dd134 | 1281 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
1282 | goto error; |
1283 | } | |
1284 | ||
1285 | /* Validate version */ | |
88076e89 | 1286 | if (version->major != VERSION_MAJOR) { |
c052142c | 1287 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", |
88076e89 | 1288 | version->major, VERSION_MAJOR); |
096102bd | 1289 | goto error_version; |
096102bd | 1290 | } |
7d268848 | 1291 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, abi_version); |
c052142c | 1292 | if (ret < 0) { |
521dd134 | 1293 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
1294 | goto error; |
1295 | } | |
88076e89 | 1296 | if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) { |
521dd134 | 1297 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
88076e89 | 1298 | abi_version->major, abi_version->minor, |
c052142c MD |
1299 | LTTNG_MODULES_ABI_MAJOR_VERSION); |
1300 | goto error; | |
1301 | } | |
1302 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
88076e89 JD |
1303 | version->major, version->minor, |
1304 | abi_version->major, abi_version->minor); | |
096102bd DG |
1305 | return 0; |
1306 | ||
1307 | error_version: | |
096102bd DG |
1308 | ret = -1; |
1309 | ||
1310 | error: | |
521dd134 | 1311 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
1312 | return ret; |
1313 | } | |
335a95b7 MD |
1314 | |
1315 | /* | |
1316 | * Kernel work-arounds called at the start of sessiond main(). | |
1317 | */ | |
1318 | int init_kernel_workarounds(void) | |
1319 | { | |
8936c33a | 1320 | int ret; |
335a95b7 MD |
1321 | FILE *fp; |
1322 | ||
1323 | /* | |
1324 | * boot_id needs to be read once before being used concurrently | |
1325 | * to deal with a Linux kernel race. A fix is proposed for | |
1326 | * upstream, but the work-around is needed for older kernels. | |
1327 | */ | |
1328 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
1329 | if (!fp) { | |
1330 | goto end_boot_id; | |
1331 | } | |
1332 | while (!feof(fp)) { | |
1333 | char buf[37] = ""; | |
1334 | ||
8936c33a DG |
1335 | ret = fread(buf, 1, sizeof(buf), fp); |
1336 | if (ret < 0) { | |
1337 | /* Ignore error, we don't really care */ | |
1338 | } | |
335a95b7 | 1339 | } |
799e2c4f MD |
1340 | ret = fclose(fp); |
1341 | if (ret) { | |
1342 | PERROR("fclose"); | |
1343 | } | |
335a95b7 | 1344 | end_boot_id: |
335a95b7 MD |
1345 | return 0; |
1346 | } | |
2f77fc4b DG |
1347 | |
1348 | /* | |
d070c424 | 1349 | * Teardown of a kernel session, keeping data required by destroy notifiers. |
2f77fc4b DG |
1350 | */ |
1351 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
1352 | { | |
82b69413 JG |
1353 | struct lttng_trace_chunk *trace_chunk; |
1354 | ||
2f77fc4b DG |
1355 | if (ksess == NULL) { |
1356 | DBG3("No kernel session when tearing down session"); | |
1357 | return; | |
1358 | } | |
1359 | ||
1360 | DBG("Tearing down kernel session"); | |
82b69413 | 1361 | trace_chunk = ksess->current_trace_chunk; |
2f77fc4b | 1362 | |
07b86b52 | 1363 | /* |
15dc512a DG |
1364 | * Destroy channels on the consumer if at least one FD has been sent and we |
1365 | * are in no output mode because the streams are in *no* monitor mode so we | |
1366 | * have to send a command to clean them up or else they leaked. | |
07b86b52 | 1367 | */ |
15dc512a | 1368 | if (!ksess->output_traces && ksess->consumer_fds_sent) { |
07b86b52 JD |
1369 | int ret; |
1370 | struct consumer_socket *socket; | |
1371 | struct lttng_ht_iter iter; | |
1372 | ||
1373 | /* For each consumer socket. */ | |
d069d577 | 1374 | rcu_read_lock(); |
07b86b52 JD |
1375 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, |
1376 | socket, node.node) { | |
1377 | struct ltt_kernel_channel *chan; | |
1378 | ||
1379 | /* For each channel, ask the consumer to destroy it. */ | |
1380 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1381 | ret = kernel_consumer_destroy_channel(socket, chan); | |
1382 | if (ret < 0) { | |
1383 | /* Consumer is probably dead. Use next socket. */ | |
1384 | continue; | |
1385 | } | |
1386 | } | |
1387 | } | |
d069d577 | 1388 | rcu_read_unlock(); |
07b86b52 JD |
1389 | } |
1390 | ||
2f77fc4b DG |
1391 | /* Close any relayd session */ |
1392 | consumer_output_send_destroy_relayd(ksess->consumer); | |
1393 | ||
1394 | trace_kernel_destroy_session(ksess); | |
82b69413 | 1395 | lttng_trace_chunk_put(trace_chunk); |
2f77fc4b | 1396 | } |
fb5f35b6 | 1397 | |
d070c424 MD |
1398 | /* Teardown of data required by destroy notifiers. */ |
1399 | void kernel_free_session(struct ltt_kernel_session *ksess) | |
1400 | { | |
1401 | if (ksess == NULL) { | |
1402 | return; | |
1403 | } | |
1404 | trace_kernel_free_session(ksess); | |
1405 | } | |
1406 | ||
fb5f35b6 DG |
1407 | /* |
1408 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
1409 | */ | |
1410 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
1411 | { | |
1412 | struct ltt_kernel_session *ksess = NULL; | |
1413 | ||
1414 | assert(kchan); | |
1415 | assert(kchan->channel); | |
1416 | ||
1417 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
1418 | ||
1419 | /* Update channel count of associated session. */ | |
1420 | if (kchan->session) { | |
1421 | /* Keep pointer reference so we can update it after the destroy. */ | |
1422 | ksess = kchan->session; | |
1423 | } | |
1424 | ||
1425 | trace_kernel_destroy_channel(kchan); | |
1426 | ||
1427 | /* | |
1428 | * At this point the kernel channel is not visible anymore. This is safe | |
1429 | * since in order to work on a visible kernel session, the tracing session | |
1430 | * lock (ltt_session.lock) MUST be acquired. | |
1431 | */ | |
1432 | if (ksess) { | |
1433 | ksess->channel_count--; | |
1434 | } | |
1435 | } | |
6dc3064a DG |
1436 | |
1437 | /* | |
1438 | * Take a snapshot for a given kernel session. | |
1439 | * | |
9a654598 | 1440 | * Return LTTNG_OK on success or else return a LTTNG_ERR code. |
6dc3064a | 1441 | */ |
fb9a95c4 JG |
1442 | enum lttng_error_code kernel_snapshot_record( |
1443 | struct ltt_kernel_session *ksess, | |
348a81dc | 1444 | const struct consumer_output *output, int wait, |
d07ceecd | 1445 | uint64_t nb_packets_per_stream) |
6dc3064a | 1446 | { |
2a06df8d | 1447 | int err, ret, saved_metadata_fd; |
9a654598 | 1448 | enum lttng_error_code status = LTTNG_OK; |
6dc3064a DG |
1449 | struct consumer_socket *socket; |
1450 | struct lttng_ht_iter iter; | |
1451 | struct ltt_kernel_metadata *saved_metadata; | |
3b967712 | 1452 | char *trace_path = NULL; |
5da88b0f | 1453 | size_t consumer_path_offset = 0; |
6dc3064a DG |
1454 | |
1455 | assert(ksess); | |
1456 | assert(ksess->consumer); | |
1457 | assert(output); | |
1458 | ||
1459 | DBG("Kernel snapshot record started"); | |
1460 | ||
1461 | /* Save current metadata since the following calls will change it. */ | |
1462 | saved_metadata = ksess->metadata; | |
1463 | saved_metadata_fd = ksess->metadata_stream_fd; | |
1464 | ||
1465 | rcu_read_lock(); | |
1466 | ||
1467 | ret = kernel_open_metadata(ksess); | |
1468 | if (ret < 0) { | |
9a654598 | 1469 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1470 | goto error; |
1471 | } | |
1472 | ||
1473 | ret = kernel_open_metadata_stream(ksess); | |
1474 | if (ret < 0) { | |
9a654598 | 1475 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1476 | goto error_open_stream; |
1477 | } | |
1478 | ||
3b967712 | 1479 | trace_path = setup_channel_trace_path(ksess->consumer, |
5da88b0f | 1480 | DEFAULT_KERNEL_TRACE_DIR, &consumer_path_offset); |
3b967712 MD |
1481 | if (!trace_path) { |
1482 | status = LTTNG_ERR_INVALID; | |
1483 | goto error; | |
1484 | } | |
6dc3064a | 1485 | /* Send metadata to consumer and snapshot everything. */ |
348a81dc | 1486 | cds_lfht_for_each_entry(output->socks->ht, &iter.iter, |
6dc3064a | 1487 | socket, node.node) { |
6dc3064a | 1488 | struct ltt_kernel_channel *chan; |
6dc3064a | 1489 | |
6dc3064a DG |
1490 | pthread_mutex_lock(socket->lock); |
1491 | /* This stream must not be monitored by the consumer. */ | |
07b86b52 | 1492 | ret = kernel_consumer_add_metadata(socket, ksess, 0); |
6dc3064a | 1493 | pthread_mutex_unlock(socket->lock); |
6dc3064a | 1494 | if (ret < 0) { |
0ed78e50 | 1495 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1496 | goto error_consumer; |
1497 | } | |
1498 | ||
1499 | /* For each channel, ask the consumer to snapshot it. */ | |
1500 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
9a654598 | 1501 | status = consumer_snapshot_channel(socket, chan->key, output, 0, |
5c786ded | 1502 | ksess->uid, ksess->gid, |
5da88b0f | 1503 | &trace_path[consumer_path_offset], wait, |
d2956687 | 1504 | nb_packets_per_stream); |
9a654598 | 1505 | if (status != LTTNG_OK) { |
2a06df8d DG |
1506 | (void) kernel_consumer_destroy_metadata(socket, |
1507 | ksess->metadata); | |
6dc3064a DG |
1508 | goto error_consumer; |
1509 | } | |
1510 | } | |
1511 | ||
1512 | /* Snapshot metadata, */ | |
9a654598 | 1513 | status = consumer_snapshot_channel(socket, ksess->metadata->key, output, |
5da88b0f MD |
1514 | 1, ksess->uid, ksess->gid, &trace_path[consumer_path_offset], |
1515 | wait, 0); | |
9a654598 | 1516 | if (status != LTTNG_OK) { |
6dc3064a DG |
1517 | goto error_consumer; |
1518 | } | |
07b86b52 JD |
1519 | |
1520 | /* | |
1521 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1522 | * it's not monitored on the consumer side. | |
1523 | */ | |
1524 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1525 | } |
1526 | ||
1527 | error_consumer: | |
1528 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1529 | err = close(ksess->metadata_stream_fd); |
1530 | if (err < 0) { | |
6dc3064a DG |
1531 | PERROR("close snapshot kernel"); |
1532 | } | |
1533 | ||
1534 | error_open_stream: | |
1535 | trace_kernel_destroy_metadata(ksess->metadata); | |
1536 | error: | |
1537 | /* Restore metadata state.*/ | |
1538 | ksess->metadata = saved_metadata; | |
1539 | ksess->metadata_stream_fd = saved_metadata_fd; | |
6dc3064a | 1540 | rcu_read_unlock(); |
3b967712 | 1541 | free(trace_path); |
9a654598 | 1542 | return status; |
6dc3064a | 1543 | } |
834978fd DG |
1544 | |
1545 | /* | |
1546 | * Get the syscall mask array from the kernel tracer. | |
1547 | * | |
1548 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1549 | * be freed. | |
1550 | */ | |
1551 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1552 | { | |
1553 | assert(syscall_mask); | |
1554 | assert(nr_bits); | |
1555 | ||
1556 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1557 | } | |
6e21424e JR |
1558 | |
1559 | /* | |
1560 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1561 | * version number. | |
1562 | * | |
1563 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1564 | * of errors. | |
1565 | */ | |
7d268848 | 1566 | int kernel_supports_ring_buffer_snapshot_sample_positions(void) |
6e21424e JR |
1567 | { |
1568 | int ret = 0; // Not supported by default | |
1569 | struct lttng_kernel_tracer_abi_version abi; | |
1570 | ||
7d268848 | 1571 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, &abi); |
6e21424e JR |
1572 | if (ret < 0) { |
1573 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1574 | goto error; | |
1575 | } | |
1576 | ||
1577 | /* | |
1578 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1579 | */ | |
1580 | if (abi.major >= 2 && abi.minor >= 3) { | |
1581 | /* Supported */ | |
1582 | ret = 1; | |
1583 | } else { | |
1584 | /* Not supported */ | |
1585 | ret = 0; | |
1586 | } | |
1587 | error: | |
1588 | return ret; | |
1589 | } | |
5c408ad8 | 1590 | |
a40a503f MD |
1591 | /* |
1592 | * Check for the support of the packet sequence number via abi version number. | |
1593 | * | |
1594 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1595 | * of errors. | |
1596 | */ | |
1597 | int kernel_supports_ring_buffer_packet_sequence_number(void) | |
1598 | { | |
1599 | int ret = 0; // Not supported by default | |
1600 | struct lttng_kernel_tracer_abi_version abi; | |
1601 | ||
1602 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, &abi); | |
1603 | if (ret < 0) { | |
1604 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1605 | goto error; | |
1606 | } | |
1607 | ||
1608 | /* | |
3029bc92 JG |
1609 | * Packet sequence number was introduced in LTTng 2.8, |
1610 | * lttng-modules ABI 2.1. | |
a40a503f | 1611 | */ |
3029bc92 | 1612 | if (abi.major >= 2 && abi.minor >= 1) { |
a40a503f MD |
1613 | /* Supported */ |
1614 | ret = 1; | |
1615 | } else { | |
1616 | /* Not supported */ | |
1617 | ret = 0; | |
1618 | } | |
1619 | error: | |
1620 | return ret; | |
1621 | } | |
1622 | ||
5c408ad8 JD |
1623 | /* |
1624 | * Rotate a kernel session. | |
1625 | * | |
d5a1b7aa | 1626 | * Return LTTNG_OK on success or else an LTTng error code. |
5c408ad8 | 1627 | */ |
d5a1b7aa | 1628 | enum lttng_error_code kernel_rotate_session(struct ltt_session *session) |
5c408ad8 JD |
1629 | { |
1630 | int ret; | |
d5a1b7aa | 1631 | enum lttng_error_code status = LTTNG_OK; |
5c408ad8 JD |
1632 | struct consumer_socket *socket; |
1633 | struct lttng_ht_iter iter; | |
1634 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1635 | ||
1636 | assert(ksess); | |
1637 | assert(ksess->consumer); | |
1638 | ||
1639 | DBG("Rotate kernel session %s started (session %" PRIu64 ")", | |
1640 | session->name, session->id); | |
1641 | ||
1642 | rcu_read_lock(); | |
1643 | ||
1644 | /* | |
1645 | * Note that this loop will end after one iteration given that there is | |
1646 | * only one kernel consumer. | |
1647 | */ | |
1648 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1649 | socket, node.node) { | |
1650 | struct ltt_kernel_channel *chan; | |
1651 | ||
d2956687 | 1652 | /* For each channel, ask the consumer to rotate it. */ |
5c408ad8 | 1653 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { |
92816cc3 JG |
1654 | DBG("Rotate kernel channel %" PRIu64 ", session %s", |
1655 | chan->key, session->name); | |
5c408ad8 JD |
1656 | ret = consumer_rotate_channel(socket, chan->key, |
1657 | ksess->uid, ksess->gid, ksess->consumer, | |
d2956687 | 1658 | /* is_metadata_channel */ false); |
5c408ad8 | 1659 | if (ret < 0) { |
d5a1b7aa | 1660 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1661 | goto error; |
1662 | } | |
1663 | } | |
1664 | ||
1665 | /* | |
1666 | * Rotate the metadata channel. | |
1667 | */ | |
22a1b931 | 1668 | ret = consumer_rotate_channel(socket, ksess->metadata->key, |
5c408ad8 | 1669 | ksess->uid, ksess->gid, ksess->consumer, |
d2956687 | 1670 | /* is_metadata_channel */ true); |
5c408ad8 | 1671 | if (ret < 0) { |
d5a1b7aa | 1672 | status = LTTNG_ERR_KERN_CONSUMER_FAIL; |
5c408ad8 JD |
1673 | goto error; |
1674 | } | |
1675 | } | |
1676 | ||
5c408ad8 JD |
1677 | error: |
1678 | rcu_read_unlock(); | |
d5a1b7aa | 1679 | return status; |
5c408ad8 | 1680 | } |
d2956687 JG |
1681 | |
1682 | enum lttng_error_code kernel_create_channel_subdirectories( | |
1683 | const struct ltt_kernel_session *ksess) | |
1684 | { | |
1685 | enum lttng_error_code ret = LTTNG_OK; | |
1686 | enum lttng_trace_chunk_status chunk_status; | |
1687 | ||
1688 | rcu_read_lock(); | |
1689 | assert(ksess->current_trace_chunk); | |
1690 | ||
1691 | /* | |
1692 | * Create the index subdirectory which will take care | |
1693 | * of implicitly creating the channel's path. | |
1694 | */ | |
1695 | chunk_status = lttng_trace_chunk_create_subdirectory( | |
1696 | ksess->current_trace_chunk, | |
1697 | DEFAULT_KERNEL_TRACE_DIR "/" DEFAULT_INDEX_DIR); | |
1698 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { | |
1699 | ret = LTTNG_ERR_CREATE_DIR_FAIL; | |
1700 | goto error; | |
1701 | } | |
1702 | error: | |
1703 | rcu_read_unlock(); | |
1704 | return ret; | |
1705 | } | |
7d268848 MD |
1706 | |
1707 | /* | |
1708 | * Setup necessary data for kernel tracer action. | |
1709 | */ | |
1710 | LTTNG_HIDDEN | |
1711 | int init_kernel_tracer(void) | |
1712 | { | |
1713 | int ret; | |
1714 | bool is_root = !getuid(); | |
1715 | ||
1716 | /* Modprobe lttng kernel modules */ | |
1717 | ret = modprobe_lttng_control(); | |
1718 | if (ret < 0) { | |
1719 | goto error; | |
1720 | } | |
1721 | ||
1722 | /* Open debugfs lttng */ | |
1723 | kernel_tracer_fd = open(module_proc_lttng, O_RDWR); | |
1724 | if (kernel_tracer_fd < 0) { | |
1725 | DBG("Failed to open %s", module_proc_lttng); | |
1726 | goto error_open; | |
1727 | } | |
1728 | ||
1729 | /* Validate kernel version */ | |
1730 | ret = kernel_validate_version(&kernel_tracer_version, | |
1731 | &kernel_tracer_abi_version); | |
1732 | if (ret < 0) { | |
1733 | goto error_version; | |
1734 | } | |
1735 | ||
1736 | ret = modprobe_lttng_data(); | |
1737 | if (ret < 0) { | |
1738 | goto error_modules; | |
1739 | } | |
1740 | ||
1741 | ret = kernel_supports_ring_buffer_snapshot_sample_positions(); | |
1742 | if (ret < 0) { | |
1743 | goto error_modules; | |
1744 | } | |
1745 | ||
1746 | if (ret < 1) { | |
1747 | WARN("Kernel tracer does not support buffer monitoring. " | |
1748 | "The monitoring timer of channels in the kernel domain " | |
1749 | "will be set to 0 (disabled)."); | |
1750 | } | |
1751 | ||
1752 | DBG("Kernel tracer fd %d", kernel_tracer_fd); | |
1753 | ||
1754 | ret = syscall_init_table(kernel_tracer_fd); | |
1755 | if (ret < 0) { | |
1756 | ERR("Unable to populate syscall table. Syscall tracing won't " | |
1757 | "work for this session daemon."); | |
1758 | } | |
1759 | return 0; | |
1760 | ||
1761 | error_version: | |
1762 | modprobe_remove_lttng_control(); | |
1763 | ret = close(kernel_tracer_fd); | |
1764 | if (ret) { | |
1765 | PERROR("close"); | |
1766 | } | |
1767 | kernel_tracer_fd = -1; | |
1768 | return LTTNG_ERR_KERN_VERSION; | |
1769 | ||
1770 | error_modules: | |
1771 | ret = close(kernel_tracer_fd); | |
1772 | if (ret) { | |
1773 | PERROR("close"); | |
1774 | } | |
1775 | ||
1776 | error_open: | |
1777 | modprobe_remove_lttng_control(); | |
1778 | ||
1779 | error: | |
1780 | WARN("No kernel tracer available"); | |
1781 | kernel_tracer_fd = -1; | |
1782 | if (!is_root) { | |
1783 | return LTTNG_ERR_NEED_ROOT_SESSIOND; | |
1784 | } else { | |
1785 | return LTTNG_ERR_KERN_NA; | |
1786 | } | |
1787 | } | |
1788 | ||
1789 | LTTNG_HIDDEN | |
1790 | void cleanup_kernel_tracer(void) | |
1791 | { | |
1792 | int ret; | |
1793 | ||
1794 | DBG2("Closing kernel fd"); | |
1795 | if (kernel_tracer_fd >= 0) { | |
1796 | ret = close(kernel_tracer_fd); | |
1797 | if (ret) { | |
1798 | PERROR("close"); | |
1799 | } | |
1800 | kernel_tracer_fd = -1; | |
1801 | } | |
1802 | DBG("Unloading kernel modules"); | |
1803 | modprobe_remove_lttng_all(); | |
1804 | free(syscall_table); | |
1805 | } | |
1806 | ||
1807 | LTTNG_HIDDEN | |
1808 | bool kernel_tracer_is_initialized(void) | |
1809 | { | |
1810 | return kernel_tracer_fd >= 0; | |
1811 | } | |
bca212a2 MD |
1812 | |
1813 | /* | |
1814 | * Clear a kernel session. | |
1815 | * | |
1816 | * Return LTTNG_OK on success or else an LTTng error code. | |
1817 | */ | |
1818 | enum lttng_error_code kernel_clear_session(struct ltt_session *session) | |
1819 | { | |
1820 | int ret; | |
1821 | enum lttng_error_code status = LTTNG_OK; | |
1822 | struct consumer_socket *socket; | |
1823 | struct lttng_ht_iter iter; | |
1824 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1825 | ||
1826 | assert(ksess); | |
1827 | assert(ksess->consumer); | |
1828 | ||
1829 | DBG("Clear kernel session %s (session %" PRIu64 ")", | |
1830 | session->name, session->id); | |
1831 | ||
1832 | rcu_read_lock(); | |
1833 | ||
1834 | if (ksess->active) { | |
1835 | ERR("Expecting inactive session %s (%" PRIu64 ")", session->name, session->id); | |
1836 | status = LTTNG_ERR_FATAL; | |
1837 | goto end; | |
1838 | } | |
1839 | ||
1840 | /* | |
1841 | * Note that this loop will end after one iteration given that there is | |
1842 | * only one kernel consumer. | |
1843 | */ | |
1844 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1845 | socket, node.node) { | |
1846 | struct ltt_kernel_channel *chan; | |
1847 | ||
1848 | /* For each channel, ask the consumer to clear it. */ | |
1849 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1850 | DBG("Clear kernel channel %" PRIu64 ", session %s", | |
1851 | chan->key, session->name); | |
1852 | ret = consumer_clear_channel(socket, chan->key); | |
1853 | if (ret < 0) { | |
1854 | goto error; | |
1855 | } | |
1856 | } | |
1857 | ||
1858 | if (!ksess->metadata) { | |
1859 | /* | |
1860 | * Nothing to do for the metadata. | |
1861 | * This is a snapshot session. | |
1862 | * The metadata is genererated on the fly. | |
1863 | */ | |
1864 | continue; | |
1865 | } | |
1866 | ||
1867 | /* | |
1868 | * Clear the metadata channel. | |
1869 | * Metadata channel is not cleared per se but we still need to | |
1870 | * perform a rotation operation on it behind the scene. | |
1871 | */ | |
1872 | ret = consumer_clear_channel(socket, ksess->metadata->key); | |
1873 | if (ret < 0) { | |
1874 | goto error; | |
1875 | } | |
1876 | } | |
1877 | ||
1878 | goto end; | |
1879 | error: | |
1880 | switch (-ret) { | |
1881 | case LTTCOMM_CONSUMERD_RELAYD_CLEAR_DISALLOWED: | |
1882 | status = LTTNG_ERR_CLEAR_RELAY_DISALLOWED; | |
1883 | break; | |
1884 | default: | |
1885 | status = LTTNG_ERR_CLEAR_FAIL_CONSUMER; | |
1886 | break; | |
1887 | } | |
1888 | end: | |
1889 | rcu_read_unlock(); | |
1890 | return status; | |
1891 | } |