Commit | Line | Data |
---|---|---|
20fe2104 | 1 | /* |
ab5be9fa | 2 | * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca> |
20fe2104 | 3 | * |
ab5be9fa | 4 | * SPDX-License-Identifier: GPL-2.0-only |
20fe2104 | 5 | * |
20fe2104 DG |
6 | */ |
7 | ||
6c1c0768 | 8 | #define _LGPL_SOURCE |
7b395890 | 9 | #include <fcntl.h> |
20fe2104 DG |
10 | #include <stdlib.h> |
11 | #include <stdio.h> | |
f34daff7 | 12 | #include <string.h> |
8c0faa1d | 13 | #include <unistd.h> |
77c7c900 | 14 | #include <inttypes.h> |
7d268848 | 15 | #include <sys/types.h> |
20fe2104 | 16 | |
990570ed | 17 | #include <common/common.h> |
82b69413 | 18 | #include <common/trace-chunk.h> |
db758600 | 19 | #include <common/kernel-ctl/kernel-ctl.h> |
c052142c | 20 | #include <common/kernel-ctl/kernel-ioctl.h> |
42224349 | 21 | #include <common/sessiond-comm/sessiond-comm.h> |
c5bf436c JG |
22 | #include <common/tracker.h> |
23 | #include <common/utils.h> | |
24 | #include <lttng/event.h> | |
25 | #include <lttng/lttng-error.h> | |
26 | #include <lttng/tracker.h> | |
1e307fab | 27 | |
7d268848 MD |
28 | #include "lttng-sessiond.h" |
29 | #include "lttng-syscall.h" | |
2f77fc4b | 30 | #include "consumer.h" |
4771f025 | 31 | #include "kernel.h" |
6dc3064a | 32 | #include "kernel-consumer.h" |
096102bd | 33 | #include "kern-modules.h" |
834978fd | 34 | #include "utils.h" |
5c408ad8 | 35 | #include "rotate.h" |
7d268848 | 36 | #include "modprobe.h" |
c5bf436c | 37 | #include "tracker.h" |
20fe2104 | 38 | |
e1f3997a JD |
39 | /* |
40 | * Key used to reference a channel between the sessiond and the consumer. This | |
41 | * is only read and updated with the session_list lock held. | |
42 | */ | |
43 | static uint64_t next_kernel_channel_key; | |
44 | ||
7d268848 MD |
45 | static const char *module_proc_lttng = "/proc/lttng"; |
46 | ||
47 | static int kernel_tracer_fd = -1; | |
48 | ||
410b78a0 FD |
49 | #include <lttng/userspace-probe.h> |
50 | #include <lttng/userspace-probe-internal.h> | |
d65106b1 | 51 | /* |
050349bb | 52 | * Add context on a kernel channel. |
df3c77c8 JG |
53 | * |
54 | * Assumes the ownership of ctx. | |
d65106b1 DG |
55 | */ |
56 | int kernel_add_channel_context(struct ltt_kernel_channel *chan, | |
645328ae | 57 | struct ltt_kernel_context *ctx) |
d65106b1 DG |
58 | { |
59 | int ret; | |
60 | ||
0525e9ae DG |
61 | assert(chan); |
62 | assert(ctx); | |
63 | ||
d65106b1 | 64 | DBG("Adding context to channel %s", chan->channel->name); |
645328ae | 65 | ret = kernctl_add_context(chan->fd, &ctx->ctx); |
d65106b1 | 66 | if (ret < 0) { |
32af2c95 | 67 | switch (-ret) { |
1ae5e83e JD |
68 | case ENOSYS: |
69 | /* Exists but not available for this kernel */ | |
70 | ret = LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE; | |
71 | goto error; | |
72 | case EEXIST: | |
b579acd9 DG |
73 | /* If EEXIST, we just ignore the error */ |
74 | ret = 0; | |
1ae5e83e JD |
75 | goto end; |
76 | default: | |
77 | PERROR("add context ioctl"); | |
78 | ret = LTTNG_ERR_KERN_CONTEXT_FAIL; | |
79 | goto error; | |
b579acd9 | 80 | } |
d65106b1 | 81 | } |
21ed98c1 | 82 | ret = 0; |
d65106b1 | 83 | |
1ae5e83e | 84 | end: |
645328ae | 85 | cds_list_add_tail(&ctx->list, &chan->ctx_list); |
ba985c3a | 86 | ctx->in_list = true; |
df3c77c8 | 87 | ctx = NULL; |
d65106b1 | 88 | error: |
df3c77c8 JG |
89 | if (ctx) { |
90 | trace_kernel_destroy_context(ctx); | |
91 | } | |
d65106b1 DG |
92 | return ret; |
93 | } | |
94 | ||
20fe2104 | 95 | /* |
050349bb DG |
96 | * Create a new kernel session, register it to the kernel tracer and add it to |
97 | * the session daemon session. | |
20fe2104 | 98 | */ |
7d268848 | 99 | int kernel_create_session(struct ltt_session *session) |
20fe2104 DG |
100 | { |
101 | int ret; | |
102 | struct ltt_kernel_session *lks; | |
103 | ||
0525e9ae DG |
104 | assert(session); |
105 | ||
54012638 | 106 | /* Allocate data structure */ |
dec56f6c | 107 | lks = trace_kernel_create_session(); |
20fe2104 | 108 | if (lks == NULL) { |
54012638 | 109 | ret = -1; |
20fe2104 DG |
110 | goto error; |
111 | } | |
112 | ||
54012638 | 113 | /* Kernel tracer session creation */ |
7d268848 | 114 | ret = kernctl_create_session(kernel_tracer_fd); |
20fe2104 | 115 | if (ret < 0) { |
df0f840b | 116 | PERROR("ioctl kernel create session"); |
20fe2104 DG |
117 | goto error; |
118 | } | |
119 | ||
20fe2104 | 120 | lks->fd = ret; |
7b395890 DG |
121 | /* Prevent fd duplication after execlp() */ |
122 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
123 | if (ret < 0) { | |
df0f840b | 124 | PERROR("fcntl session fd"); |
7b395890 DG |
125 | } |
126 | ||
53632229 | 127 | lks->id = session->id; |
3bd1e081 | 128 | lks->consumer_fds_sent = 0; |
8c0faa1d | 129 | session->kernel_session = lks; |
8c0faa1d DG |
130 | |
131 | DBG("Kernel session created (fd: %d)", lks->fd); | |
20fe2104 | 132 | |
8ff4109e JR |
133 | /* |
134 | * This is necessary since the creation time is present in the session | |
135 | * name when it is generated. | |
136 | */ | |
137 | if (session->has_auto_generated_name) { | |
138 | ret = kernctl_session_set_name(lks->fd, DEFAULT_SESSION_NAME); | |
139 | } else { | |
140 | ret = kernctl_session_set_name(lks->fd, session->name); | |
141 | } | |
142 | if (ret) { | |
143 | WARN("Could not set kernel session name for session %" PRIu64 " name: %s", | |
144 | session->id, session->name); | |
145 | } | |
146 | ||
e04b2181 JR |
147 | ret = kernctl_session_set_creation_time(lks->fd, session->creation_time); |
148 | if (ret) { | |
149 | WARN("Could not set kernel session creation time for session %" PRIu64 " name: %s", | |
150 | session->id, session->name); | |
151 | } | |
152 | ||
20fe2104 DG |
153 | return 0; |
154 | ||
155 | error: | |
5f62c685 DG |
156 | if (lks) { |
157 | trace_kernel_destroy_session(lks); | |
d070c424 | 158 | trace_kernel_free_session(lks); |
5f62c685 | 159 | } |
20fe2104 DG |
160 | return ret; |
161 | } | |
162 | ||
163 | /* | |
050349bb DG |
164 | * Create a kernel channel, register it to the kernel tracer and add it to the |
165 | * kernel session. | |
20fe2104 | 166 | */ |
050349bb | 167 | int kernel_create_channel(struct ltt_kernel_session *session, |
fdd9eb17 | 168 | struct lttng_channel *chan) |
20fe2104 DG |
169 | { |
170 | int ret; | |
171 | struct ltt_kernel_channel *lkc; | |
20fe2104 | 172 | |
0525e9ae DG |
173 | assert(session); |
174 | assert(chan); | |
0525e9ae | 175 | |
54012638 | 176 | /* Allocate kernel channel */ |
fdd9eb17 | 177 | lkc = trace_kernel_create_channel(chan); |
54012638 | 178 | if (lkc == NULL) { |
20fe2104 DG |
179 | goto error; |
180 | } | |
181 | ||
ecc48a90 | 182 | DBG3("Kernel create channel %s with attr: %d, %" PRIu64 ", %" PRIu64 ", %u, %u, %d, %d", |
fdd9eb17 | 183 | chan->name, lkc->channel->attr.overwrite, |
173af62f DG |
184 | lkc->channel->attr.subbuf_size, lkc->channel->attr.num_subbuf, |
185 | lkc->channel->attr.switch_timer_interval, lkc->channel->attr.read_timer_interval, | |
ecc48a90 | 186 | lkc->channel->attr.live_timer_interval, lkc->channel->attr.output); |
173af62f | 187 | |
54012638 | 188 | /* Kernel tracer channel creation */ |
f3ed775e | 189 | ret = kernctl_create_channel(session->fd, &lkc->channel->attr); |
20fe2104 | 190 | if (ret < 0) { |
df0f840b | 191 | PERROR("ioctl kernel create channel"); |
20fe2104 DG |
192 | goto error; |
193 | } | |
194 | ||
54012638 | 195 | /* Setup the channel fd */ |
20fe2104 | 196 | lkc->fd = ret; |
7b395890 DG |
197 | /* Prevent fd duplication after execlp() */ |
198 | ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC); | |
199 | if (ret < 0) { | |
df0f840b | 200 | PERROR("fcntl session fd"); |
7b395890 DG |
201 | } |
202 | ||
54012638 | 203 | /* Add channel to session */ |
8c0faa1d DG |
204 | cds_list_add(&lkc->list, &session->channel_list.head); |
205 | session->channel_count++; | |
fb5f35b6 | 206 | lkc->session = session; |
e1f3997a | 207 | lkc->key = ++next_kernel_channel_key; |
20fe2104 | 208 | |
e1f3997a JD |
209 | DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")", |
210 | lkc->channel->name, lkc->fd, lkc->key); | |
20fe2104 DG |
211 | |
212 | return 0; | |
213 | ||
214 | error: | |
5f62c685 DG |
215 | if (lkc) { |
216 | free(lkc->channel); | |
217 | free(lkc); | |
218 | } | |
54012638 | 219 | return -1; |
20fe2104 | 220 | } |
f34daff7 | 221 | |
410b78a0 FD |
222 | /* |
223 | * Compute the offset of the instrumentation byte in the binary based on the | |
224 | * function probe location using the ELF lookup method. | |
225 | * | |
226 | * Returns 0 on success and set the offset out parameter to the offset of the | |
227 | * elf symbol | |
228 | * Returns -1 on error | |
229 | */ | |
230 | static | |
231 | int extract_userspace_probe_offset_function_elf( | |
87597c2c | 232 | const struct lttng_userspace_probe_location *probe_location, |
0a398bc4 | 233 | uid_t uid, gid_t gid, uint64_t *offset) |
410b78a0 FD |
234 | { |
235 | int fd; | |
236 | int ret = 0; | |
237 | const char *symbol = NULL; | |
87597c2c | 238 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
239 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; |
240 | ||
410b78a0 FD |
241 | assert(lttng_userspace_probe_location_get_type(probe_location) == |
242 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_FUNCTION); | |
243 | ||
244 | lookup = lttng_userspace_probe_location_get_lookup_method( | |
245 | probe_location); | |
246 | if (!lookup) { | |
247 | ret = -1; | |
248 | goto end; | |
249 | } | |
250 | ||
251 | lookup_method_type = | |
252 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
253 | ||
254 | assert(lookup_method_type == | |
255 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF); | |
256 | ||
257 | symbol = lttng_userspace_probe_location_function_get_function_name( | |
258 | probe_location); | |
259 | if (!symbol) { | |
260 | ret = -1; | |
261 | goto end; | |
262 | } | |
263 | ||
264 | fd = lttng_userspace_probe_location_function_get_binary_fd(probe_location); | |
265 | if (fd < 0) { | |
266 | ret = -1; | |
267 | goto end; | |
268 | } | |
269 | ||
0a398bc4 | 270 | ret = run_as_extract_elf_symbol_offset(fd, symbol, uid, gid, offset); |
410b78a0 FD |
271 | if (ret < 0) { |
272 | DBG("userspace probe offset calculation failed for " | |
273 | "function %s", symbol); | |
274 | goto end; | |
275 | } | |
276 | ||
277 | DBG("userspace probe elf offset for %s is 0x%jd", symbol, (intmax_t)(*offset)); | |
278 | end: | |
279 | return ret; | |
280 | } | |
281 | ||
282 | /* | |
283 | * Compute the offsets of the instrumentation bytes in the binary based on the | |
284 | * tracepoint probe location using the SDT lookup method. This function | |
285 | * allocates the offsets buffer, the caller must free it. | |
286 | * | |
287 | * Returns 0 on success and set the offset out parameter to the offsets of the | |
288 | * SDT tracepoint. | |
289 | * Returns -1 on error. | |
290 | */ | |
291 | static | |
292 | int extract_userspace_probe_offset_tracepoint_sdt( | |
87597c2c | 293 | const struct lttng_userspace_probe_location *probe_location, |
0a398bc4 | 294 | uid_t uid, gid_t gid, uint64_t **offsets, |
410b78a0 FD |
295 | uint32_t *offsets_count) |
296 | { | |
297 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; | |
87597c2c | 298 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
299 | const char *probe_name = NULL, *provider_name = NULL; |
300 | int ret = 0; | |
301 | int fd, i; | |
302 | ||
303 | assert(lttng_userspace_probe_location_get_type(probe_location) == | |
304 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_TRACEPOINT); | |
305 | ||
306 | lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); | |
307 | if (!lookup) { | |
308 | ret = -1; | |
309 | goto end; | |
310 | } | |
311 | ||
312 | lookup_method_type = | |
313 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
314 | ||
315 | assert(lookup_method_type == | |
316 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT); | |
317 | ||
318 | ||
319 | probe_name = lttng_userspace_probe_location_tracepoint_get_probe_name( | |
320 | probe_location); | |
321 | if (!probe_name) { | |
322 | ret = -1; | |
323 | goto end; | |
324 | } | |
325 | ||
326 | provider_name = lttng_userspace_probe_location_tracepoint_get_provider_name( | |
327 | probe_location); | |
328 | if (!provider_name) { | |
329 | ret = -1; | |
330 | goto end; | |
331 | } | |
332 | ||
333 | fd = lttng_userspace_probe_location_tracepoint_get_binary_fd(probe_location); | |
334 | if (fd < 0) { | |
335 | ret = -1; | |
336 | goto end; | |
337 | } | |
338 | ||
339 | ret = run_as_extract_sdt_probe_offsets(fd, provider_name, probe_name, | |
0a398bc4 | 340 | uid, gid, offsets, offsets_count); |
410b78a0 FD |
341 | if (ret < 0) { |
342 | DBG("userspace probe offset calculation failed for sdt " | |
343 | "probe %s:%s", provider_name, probe_name); | |
344 | goto end; | |
345 | } | |
346 | ||
347 | if (*offsets_count == 0) { | |
348 | DBG("no userspace probe offset found"); | |
349 | goto end; | |
350 | } | |
351 | ||
352 | DBG("%u userspace probe SDT offsets found for %s:%s at:", | |
353 | *offsets_count, provider_name, probe_name); | |
354 | for (i = 0; i < *offsets_count; i++) { | |
355 | DBG("\t0x%jd", (intmax_t)((*offsets)[i])); | |
356 | } | |
357 | end: | |
358 | return ret; | |
359 | } | |
360 | ||
410b78a0 | 361 | static |
0a398bc4 FD |
362 | int userspace_probe_add_callsite( |
363 | const struct lttng_userspace_probe_location *location, | |
364 | uid_t uid, gid_t gid, int fd) | |
410b78a0 | 365 | { |
87597c2c | 366 | const struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL; |
410b78a0 | 367 | enum lttng_userspace_probe_location_lookup_method_type type; |
410b78a0 FD |
368 | int ret; |
369 | ||
0a398bc4 | 370 | lookup_method = lttng_userspace_probe_location_get_lookup_method(location); |
410b78a0 FD |
371 | if (!lookup_method) { |
372 | ret = -1; | |
373 | goto end; | |
374 | } | |
375 | ||
376 | type = lttng_userspace_probe_location_lookup_method_get_type(lookup_method); | |
377 | switch (type) { | |
378 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: | |
379 | { | |
380 | struct lttng_kernel_event_callsite callsite; | |
381 | uint64_t offset; | |
382 | ||
0a398bc4 FD |
383 | ret = extract_userspace_probe_offset_function_elf(location, |
384 | uid, gid, &offset); | |
410b78a0 FD |
385 | if (ret) { |
386 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
387 | goto end; | |
388 | } | |
389 | ||
390 | callsite.u.uprobe.offset = offset; | |
391 | ret = kernctl_add_callsite(fd, &callsite); | |
392 | if (ret) { | |
0a398bc4 | 393 | WARN("Failed to add callsite to ELF userspace probe."); |
410b78a0 FD |
394 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
395 | goto end; | |
396 | } | |
397 | break; | |
398 | } | |
399 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: | |
400 | { | |
401 | int i; | |
402 | uint64_t *offsets = NULL; | |
403 | uint32_t offsets_count; | |
404 | struct lttng_kernel_event_callsite callsite; | |
405 | ||
406 | /* | |
407 | * This call allocates the offsets buffer. This buffer must be freed | |
408 | * by the caller | |
409 | */ | |
0a398bc4 FD |
410 | ret = extract_userspace_probe_offset_tracepoint_sdt(location, |
411 | uid, gid, &offsets, &offsets_count); | |
410b78a0 FD |
412 | if (ret) { |
413 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
414 | goto end; | |
415 | } | |
416 | for (i = 0; i < offsets_count; i++) { | |
417 | callsite.u.uprobe.offset = offsets[i]; | |
418 | ret = kernctl_add_callsite(fd, &callsite); | |
419 | if (ret) { | |
0a398bc4 | 420 | WARN("Failed to add callsite to SDT userspace probe"); |
410b78a0 FD |
421 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
422 | free(offsets); | |
423 | goto end; | |
424 | } | |
425 | } | |
426 | free(offsets); | |
427 | break; | |
428 | } | |
429 | default: | |
430 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
431 | goto end; | |
432 | } | |
433 | end: | |
434 | return ret; | |
435 | } | |
436 | ||
0a398bc4 FD |
437 | /* |
438 | * Extract the offsets of the instrumentation point for the different lookup | |
439 | * methods. | |
440 | */ | |
441 | static | |
442 | int userspace_probe_event_add_callsites(struct lttng_event *ev, | |
443 | struct ltt_kernel_session *session, int fd) | |
444 | { | |
445 | int ret; | |
446 | const struct lttng_userspace_probe_location *location = NULL; | |
447 | ||
448 | assert(ev); | |
449 | assert(ev->type == LTTNG_EVENT_USERSPACE_PROBE); | |
450 | ||
451 | location = lttng_event_get_userspace_probe_location(ev); | |
452 | if (!location) { | |
453 | ret = -1; | |
454 | goto end; | |
455 | } | |
456 | ||
457 | ret = userspace_probe_add_callsite(location, session->uid, session->gid, | |
458 | fd); | |
459 | if (ret) { | |
460 | WARN("Failed to add callsite to userspace probe event '%s'", | |
461 | ev->name); | |
462 | } | |
463 | ||
464 | end: | |
465 | return ret; | |
466 | } | |
467 | ||
f34daff7 | 468 | /* |
050349bb DG |
469 | * Create a kernel event, enable it to the kernel tracer and add it to the |
470 | * channel event list of the kernel session. | |
49d21f93 | 471 | * We own filter_expression and filter. |
f34daff7 | 472 | */ |
050349bb | 473 | int kernel_create_event(struct lttng_event *ev, |
00a62084 MD |
474 | struct ltt_kernel_channel *channel, |
475 | char *filter_expression, | |
476 | struct lttng_filter_bytecode *filter) | |
f34daff7 | 477 | { |
71a3bb01 FD |
478 | int err, fd; |
479 | enum lttng_error_code ret; | |
f34daff7 | 480 | struct ltt_kernel_event *event; |
f34daff7 | 481 | |
0525e9ae DG |
482 | assert(ev); |
483 | assert(channel); | |
484 | ||
a969e101 | 485 | /* We pass ownership of filter_expression and filter */ |
71a3bb01 FD |
486 | ret = trace_kernel_create_event(ev, filter_expression, |
487 | filter, &event); | |
488 | if (ret != LTTNG_OK) { | |
f34daff7 DG |
489 | goto error; |
490 | } | |
491 | ||
71a3bb01 FD |
492 | fd = kernctl_create_event(channel->fd, event->event); |
493 | if (fd < 0) { | |
494 | switch (-fd) { | |
bd29c13d | 495 | case EEXIST: |
71a3bb01 | 496 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
bd29c13d DG |
497 | break; |
498 | case ENOSYS: | |
499 | WARN("Event type not implemented"); | |
71a3bb01 | 500 | ret = LTTNG_ERR_KERN_EVENT_ENOSYS; |
bd29c13d | 501 | break; |
8197a339 DG |
502 | case ENOENT: |
503 | WARN("Event %s not found!", ev->name); | |
71a3bb01 | 504 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
8197a339 | 505 | break; |
bd29c13d | 506 | default: |
71a3bb01 | 507 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
d87bfb32 DG |
508 | PERROR("create event ioctl"); |
509 | } | |
e953ef25 | 510 | goto free_event; |
8c0faa1d | 511 | } |
f34daff7 | 512 | |
d0ae4ea8 | 513 | event->type = ev->type; |
71a3bb01 | 514 | event->fd = fd; |
7b395890 | 515 | /* Prevent fd duplication after execlp() */ |
71a3bb01 FD |
516 | err = fcntl(event->fd, F_SETFD, FD_CLOEXEC); |
517 | if (err < 0) { | |
df0f840b | 518 | PERROR("fcntl session fd"); |
7b395890 DG |
519 | } |
520 | ||
00a62084 | 521 | if (filter) { |
71a3bb01 FD |
522 | err = kernctl_filter(event->fd, filter); |
523 | if (err < 0) { | |
524 | switch (-err) { | |
525 | case ENOMEM: | |
526 | ret = LTTNG_ERR_FILTER_NOMEM; | |
527 | break; | |
528 | default: | |
529 | ret = LTTNG_ERR_FILTER_INVAL; | |
530 | break; | |
531 | } | |
00a62084 MD |
532 | goto filter_error; |
533 | } | |
534 | } | |
535 | ||
dcabc190 | 536 | if (ev->type == LTTNG_EVENT_USERSPACE_PROBE) { |
0a398bc4 FD |
537 | ret = userspace_probe_event_add_callsites(ev, channel->session, |
538 | event->fd); | |
dcabc190 FD |
539 | if (ret) { |
540 | goto add_callsite_error; | |
541 | } | |
542 | } | |
543 | ||
71a3bb01 FD |
544 | err = kernctl_enable(event->fd); |
545 | if (err < 0) { | |
546 | switch (-err) { | |
00a62084 MD |
547 | case EEXIST: |
548 | ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
549 | break; | |
550 | default: | |
551 | PERROR("enable kernel event"); | |
71a3bb01 | 552 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
00a62084 MD |
553 | break; |
554 | } | |
555 | goto enable_error; | |
556 | } | |
557 | ||
f3ed775e DG |
558 | /* Add event to event list */ |
559 | cds_list_add(&event->list, &channel->events_list.head); | |
cbbbb275 DG |
560 | channel->event_count++; |
561 | ||
e953ef25 DG |
562 | DBG("Event %s created (fd: %d)", ev->name, event->fd); |
563 | ||
564 | return 0; | |
565 | ||
dcabc190 | 566 | add_callsite_error: |
00a62084 MD |
567 | enable_error: |
568 | filter_error: | |
569 | { | |
570 | int closeret; | |
571 | ||
572 | closeret = close(event->fd); | |
573 | if (closeret) { | |
574 | PERROR("close event fd"); | |
575 | } | |
576 | } | |
e953ef25 DG |
577 | free_event: |
578 | free(event); | |
579 | error: | |
d87bfb32 | 580 | return ret; |
e953ef25 DG |
581 | } |
582 | ||
26cc6b4e | 583 | /* |
050349bb | 584 | * Disable a kernel channel. |
26cc6b4e DG |
585 | */ |
586 | int kernel_disable_channel(struct ltt_kernel_channel *chan) | |
587 | { | |
588 | int ret; | |
589 | ||
0525e9ae DG |
590 | assert(chan); |
591 | ||
26cc6b4e DG |
592 | ret = kernctl_disable(chan->fd); |
593 | if (ret < 0) { | |
df0f840b | 594 | PERROR("disable chan ioctl"); |
26cc6b4e DG |
595 | goto error; |
596 | } | |
597 | ||
598 | chan->enabled = 0; | |
e1f3997a JD |
599 | DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")", |
600 | chan->channel->name, chan->fd, chan->key); | |
26cc6b4e DG |
601 | |
602 | return 0; | |
603 | ||
604 | error: | |
605 | return ret; | |
606 | } | |
607 | ||
d36b8583 | 608 | /* |
050349bb | 609 | * Enable a kernel channel. |
d36b8583 DG |
610 | */ |
611 | int kernel_enable_channel(struct ltt_kernel_channel *chan) | |
612 | { | |
613 | int ret; | |
614 | ||
0525e9ae DG |
615 | assert(chan); |
616 | ||
d36b8583 | 617 | ret = kernctl_enable(chan->fd); |
32af2c95 | 618 | if (ret < 0 && ret != -EEXIST) { |
df0f840b | 619 | PERROR("Enable kernel chan"); |
d36b8583 DG |
620 | goto error; |
621 | } | |
622 | ||
623 | chan->enabled = 1; | |
e1f3997a JD |
624 | DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")", |
625 | chan->channel->name, chan->fd, chan->key); | |
d36b8583 DG |
626 | |
627 | return 0; | |
628 | ||
629 | error: | |
630 | return ret; | |
631 | } | |
632 | ||
19e70852 | 633 | /* |
050349bb | 634 | * Enable a kernel event. |
19e70852 DG |
635 | */ |
636 | int kernel_enable_event(struct ltt_kernel_event *event) | |
637 | { | |
638 | int ret; | |
639 | ||
0525e9ae DG |
640 | assert(event); |
641 | ||
19e70852 | 642 | ret = kernctl_enable(event->fd); |
42224349 | 643 | if (ret < 0) { |
32af2c95 | 644 | switch (-ret) { |
42224349 | 645 | case EEXIST: |
f73fabfd | 646 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
647 | break; |
648 | default: | |
649 | PERROR("enable kernel event"); | |
650 | break; | |
651 | } | |
19e70852 DG |
652 | goto error; |
653 | } | |
654 | ||
655 | event->enabled = 1; | |
656 | DBG("Kernel event %s enabled (fd: %d)", event->event->name, event->fd); | |
657 | ||
658 | return 0; | |
659 | ||
660 | error: | |
d36b8583 | 661 | return ret; |
19e70852 DG |
662 | } |
663 | ||
e953ef25 | 664 | /* |
050349bb | 665 | * Disable a kernel event. |
e953ef25 | 666 | */ |
19e70852 | 667 | int kernel_disable_event(struct ltt_kernel_event *event) |
e953ef25 DG |
668 | { |
669 | int ret; | |
19e70852 | 670 | |
0525e9ae DG |
671 | assert(event); |
672 | ||
19e70852 | 673 | ret = kernctl_disable(event->fd); |
42224349 | 674 | if (ret < 0) { |
32af2c95 | 675 | switch (-ret) { |
42224349 | 676 | case EEXIST: |
f73fabfd | 677 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
678 | break; |
679 | default: | |
680 | PERROR("disable kernel event"); | |
681 | break; | |
682 | } | |
19e70852 | 683 | goto error; |
e953ef25 | 684 | } |
f3ed775e | 685 | |
19e70852 DG |
686 | event->enabled = 0; |
687 | DBG("Kernel event %s disabled (fd: %d)", event->event->name, event->fd); | |
688 | ||
f34daff7 DG |
689 | return 0; |
690 | ||
691 | error: | |
d36b8583 | 692 | return ret; |
f34daff7 | 693 | } |
aaf26714 | 694 | |
159b042f JG |
695 | static |
696 | struct process_attr_tracker *_kernel_get_process_attr_tracker( | |
55c9e7ca | 697 | struct ltt_kernel_session *session, |
159b042f | 698 | enum lttng_process_attr process_attr) |
55c9e7ca | 699 | { |
159b042f JG |
700 | switch (process_attr) { |
701 | case LTTNG_PROCESS_ATTR_PROCESS_ID: | |
702 | return session->tracker_pid; | |
703 | case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID: | |
704 | return session->tracker_vpid; | |
705 | case LTTNG_PROCESS_ATTR_USER_ID: | |
706 | return session->tracker_uid; | |
707 | case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID: | |
708 | return session->tracker_vuid; | |
709 | case LTTNG_PROCESS_ATTR_GROUP_ID: | |
710 | return session->tracker_gid; | |
711 | case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID: | |
712 | return session->tracker_vgid; | |
55c9e7ca JR |
713 | default: |
714 | return NULL; | |
715 | } | |
716 | } | |
6e911cad | 717 | |
159b042f | 718 | const struct process_attr_tracker *kernel_get_process_attr_tracker( |
55c9e7ca | 719 | struct ltt_kernel_session *session, |
159b042f | 720 | enum lttng_process_attr process_attr) |
ccf10263 | 721 | { |
159b042f JG |
722 | return (const struct process_attr_tracker *) |
723 | _kernel_get_process_attr_tracker(session, process_attr); | |
724 | } | |
7c493d31 | 725 | |
159b042f JG |
726 | enum lttng_error_code kernel_process_attr_tracker_set_tracking_policy( |
727 | struct ltt_kernel_session *session, | |
728 | enum lttng_process_attr process_attr, | |
729 | enum lttng_tracking_policy policy) | |
730 | { | |
731 | int ret; | |
732 | enum lttng_error_code ret_code = LTTNG_OK; | |
733 | struct process_attr_tracker *tracker = | |
734 | _kernel_get_process_attr_tracker(session, process_attr); | |
735 | enum lttng_tracking_policy previous_policy; | |
55c9e7ca | 736 | |
159b042f JG |
737 | if (!tracker) { |
738 | ret_code = LTTNG_ERR_INVALID; | |
739 | goto end; | |
7c493d31 | 740 | } |
ccf10263 | 741 | |
159b042f JG |
742 | previous_policy = process_attr_tracker_get_tracking_policy(tracker); |
743 | ret = process_attr_tracker_set_tracking_policy(tracker, policy); | |
744 | if (ret) { | |
745 | ret_code = LTTNG_ERR_UNK; | |
746 | goto end; | |
55c9e7ca | 747 | } |
7c493d31 | 748 | |
159b042f | 749 | if (previous_policy == policy) { |
55c9e7ca | 750 | goto end; |
7c493d31 | 751 | } |
55c9e7ca | 752 | |
159b042f JG |
753 | switch (policy) { |
754 | case LTTNG_TRACKING_POLICY_INCLUDE_ALL: | |
755 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
756 | /* | |
757 | * Maintain a special case for the process ID process | |
758 | * attribute tracker as it was the only supported | |
759 | * attribute prior to 2.12. | |
760 | */ | |
761 | ret = kernctl_track_pid(session->fd, -1); | |
762 | } else { | |
763 | ret = kernctl_track_id(session->fd, process_attr, -1); | |
55c9e7ca JR |
764 | } |
765 | break; | |
159b042f JG |
766 | case LTTNG_TRACKING_POLICY_EXCLUDE_ALL: |
767 | case LTTNG_TRACKING_POLICY_INCLUDE_SET: | |
768 | /* fall-through. */ | |
769 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
770 | /* | |
771 | * Maintain a special case for the process ID process | |
772 | * attribute tracker as it was the only supported | |
773 | * attribute prior to 2.12. | |
774 | */ | |
775 | ret = kernctl_untrack_pid(session->fd, -1); | |
776 | } else { | |
777 | ret = kernctl_untrack_id(session->fd, process_attr, -1); | |
55c9e7ca JR |
778 | } |
779 | break; | |
780 | default: | |
159b042f | 781 | abort(); |
55c9e7ca | 782 | } |
159b042f | 783 | /* kern-ctl error handling */ |
32af2c95 | 784 | switch (-ret) { |
159b042f JG |
785 | case 0: |
786 | ret_code = LTTNG_OK; | |
787 | break; | |
7c493d31 | 788 | case EINVAL: |
159b042f | 789 | ret_code = LTTNG_ERR_INVALID; |
55c9e7ca | 790 | break; |
7c493d31 | 791 | case ENOMEM: |
159b042f | 792 | ret_code = LTTNG_ERR_NOMEM; |
55c9e7ca JR |
793 | break; |
794 | case EEXIST: | |
159b042f | 795 | ret_code = LTTNG_ERR_PROCESS_ATTR_EXISTS; |
55c9e7ca | 796 | break; |
7c493d31 | 797 | default: |
159b042f | 798 | ret_code = LTTNG_ERR_UNK; |
55c9e7ca JR |
799 | break; |
800 | } | |
55c9e7ca | 801 | end: |
159b042f | 802 | return ret_code; |
ccf10263 MD |
803 | } |
804 | ||
159b042f | 805 | enum lttng_error_code kernel_process_attr_tracker_inclusion_set_add_value( |
55c9e7ca | 806 | struct ltt_kernel_session *session, |
159b042f JG |
807 | enum lttng_process_attr process_attr, |
808 | const struct process_attr_value *value) | |
a5dfbb9d | 809 | { |
159b042f JG |
810 | int ret, integral_value; |
811 | enum lttng_error_code ret_code; | |
812 | struct process_attr_tracker *tracker; | |
813 | enum process_attr_tracker_status status; | |
a5dfbb9d | 814 | |
159b042f JG |
815 | /* |
816 | * Convert process attribute tracker value to the integral | |
817 | * representation required by the kern-ctl API. | |
818 | */ | |
819 | switch (process_attr) { | |
820 | case LTTNG_PROCESS_ATTR_PROCESS_ID: | |
821 | case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID: | |
822 | integral_value = (int) value->value.pid; | |
55c9e7ca | 823 | break; |
159b042f JG |
824 | case LTTNG_PROCESS_ATTR_USER_ID: |
825 | case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID: | |
826 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME) { | |
827 | uid_t uid; | |
828 | ||
829 | ret_code = utils_user_id_from_name( | |
830 | value->value.user_name, &uid); | |
831 | if (ret_code != LTTNG_OK) { | |
832 | goto end; | |
833 | } | |
834 | integral_value = (int) uid; | |
835 | } else { | |
836 | integral_value = (int) value->value.uid; | |
55c9e7ca JR |
837 | } |
838 | break; | |
159b042f JG |
839 | case LTTNG_PROCESS_ATTR_GROUP_ID: |
840 | case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID: | |
841 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME) { | |
842 | gid_t gid; | |
843 | ||
844 | ret_code = utils_group_id_from_name( | |
845 | value->value.group_name, &gid); | |
846 | if (ret_code != LTTNG_OK) { | |
847 | goto end; | |
848 | } | |
849 | integral_value = (int) gid; | |
850 | } else { | |
851 | integral_value = (int) value->value.gid; | |
a5dfbb9d | 852 | } |
55c9e7ca JR |
853 | break; |
854 | default: | |
159b042f JG |
855 | ret_code = LTTNG_ERR_INVALID; |
856 | goto end; | |
55c9e7ca JR |
857 | } |
858 | ||
159b042f JG |
859 | tracker = _kernel_get_process_attr_tracker(session, process_attr); |
860 | if (!tracker) { | |
861 | ret_code = LTTNG_ERR_INVALID; | |
862 | goto end; | |
863 | } | |
864 | ||
865 | status = process_attr_tracker_inclusion_set_add_value(tracker, value); | |
866 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
867 | switch (status) { | |
868 | case PROCESS_ATTR_TRACKER_STATUS_EXISTS: | |
869 | ret_code = LTTNG_ERR_PROCESS_ATTR_EXISTS; | |
870 | break; | |
871 | case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY: | |
872 | ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY; | |
873 | break; | |
874 | case PROCESS_ATTR_TRACKER_STATUS_ERROR: | |
875 | default: | |
876 | ret_code = LTTNG_ERR_UNK; | |
877 | break; | |
878 | } | |
879 | goto end; | |
880 | } | |
881 | ||
882 | DBG("Kernel track %s %d for session id %" PRIu64, | |
883 | lttng_process_attr_to_string(process_attr), | |
884 | integral_value, session->id); | |
885 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
886 | /* | |
887 | * Maintain a special case for the process ID process attribute | |
888 | * tracker as it was the only supported attribute prior to 2.12. | |
889 | */ | |
890 | ret = kernctl_track_pid(session->fd, integral_value); | |
891 | } else { | |
892 | ret = kernctl_track_id( | |
893 | session->fd, process_attr, integral_value); | |
894 | } | |
895 | if (ret == 0) { | |
896 | ret_code = LTTNG_OK; | |
897 | goto end; | |
898 | } | |
899 | ||
900 | kernel_wait_quiescent(); | |
901 | ||
902 | /* kern-ctl error handling */ | |
55c9e7ca | 903 | switch (-ret) { |
159b042f JG |
904 | case 0: |
905 | ret_code = LTTNG_OK; | |
906 | break; | |
55c9e7ca | 907 | case EINVAL: |
159b042f | 908 | ret_code = LTTNG_ERR_INVALID; |
55c9e7ca JR |
909 | break; |
910 | case ENOMEM: | |
159b042f | 911 | ret_code = LTTNG_ERR_NOMEM; |
55c9e7ca JR |
912 | break; |
913 | case EEXIST: | |
159b042f | 914 | ret_code = LTTNG_ERR_PROCESS_ATTR_EXISTS; |
55c9e7ca JR |
915 | break; |
916 | default: | |
159b042f | 917 | ret_code = LTTNG_ERR_UNK; |
55c9e7ca | 918 | break; |
a5dfbb9d MD |
919 | } |
920 | ||
159b042f JG |
921 | /* Attempt to remove the value from the tracker. */ |
922 | status = process_attr_tracker_inclusion_set_remove_value( | |
923 | tracker, value); | |
924 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
925 | ERR("Failed to roll-back the tracking of kernel %s process attribute %d while handling a kern-ctl error", | |
926 | lttng_process_attr_to_string(process_attr), | |
927 | integral_value); | |
55c9e7ca | 928 | } |
a5dfbb9d | 929 | end: |
159b042f | 930 | return ret_code; |
55c9e7ca | 931 | } |
a5dfbb9d | 932 | |
159b042f | 933 | enum lttng_error_code kernel_process_attr_tracker_inclusion_set_remove_value( |
55c9e7ca | 934 | struct ltt_kernel_session *session, |
159b042f JG |
935 | enum lttng_process_attr process_attr, |
936 | const struct process_attr_value *value) | |
55c9e7ca | 937 | { |
159b042f JG |
938 | int ret, integral_value; |
939 | enum lttng_error_code ret_code; | |
940 | struct process_attr_tracker *tracker; | |
941 | enum process_attr_tracker_status status; | |
942 | ||
943 | /* | |
944 | * Convert process attribute tracker value to the integral | |
945 | * representation required by the kern-ctl API. | |
946 | */ | |
947 | switch (process_attr) { | |
948 | case LTTNG_PROCESS_ATTR_PROCESS_ID: | |
949 | case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID: | |
950 | integral_value = (int) value->value.pid; | |
951 | break; | |
952 | case LTTNG_PROCESS_ATTR_USER_ID: | |
953 | case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID: | |
954 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME) { | |
955 | uid_t uid; | |
956 | ||
957 | ret_code = utils_user_id_from_name( | |
958 | value->value.user_name, &uid); | |
959 | if (ret_code != LTTNG_OK) { | |
960 | goto end; | |
961 | } | |
962 | integral_value = (int) uid; | |
963 | } else { | |
964 | integral_value = (int) value->value.uid; | |
965 | } | |
966 | break; | |
967 | case LTTNG_PROCESS_ATTR_GROUP_ID: | |
968 | case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID: | |
969 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME) { | |
970 | gid_t gid; | |
971 | ||
972 | ret_code = utils_group_id_from_name( | |
973 | value->value.group_name, &gid); | |
974 | if (ret_code != LTTNG_OK) { | |
975 | goto end; | |
976 | } | |
977 | integral_value = (int) gid; | |
978 | } else { | |
979 | integral_value = (int) value->value.gid; | |
980 | } | |
981 | break; | |
982 | default: | |
983 | ret_code = LTTNG_ERR_INVALID; | |
984 | goto end; | |
985 | } | |
55c9e7ca | 986 | |
159b042f JG |
987 | tracker = _kernel_get_process_attr_tracker(session, process_attr); |
988 | if (!tracker) { | |
989 | ret_code = LTTNG_ERR_INVALID; | |
a7a533cd | 990 | goto end; |
a5dfbb9d | 991 | } |
a7a533cd | 992 | |
159b042f JG |
993 | status = process_attr_tracker_inclusion_set_remove_value( |
994 | tracker, value); | |
995 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
996 | switch (status) { | |
997 | case PROCESS_ATTR_TRACKER_STATUS_MISSING: | |
998 | ret_code = LTTNG_ERR_PROCESS_ATTR_MISSING; | |
999 | break; | |
1000 | case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY: | |
1001 | ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY; | |
1002 | break; | |
1003 | case PROCESS_ATTR_TRACKER_STATUS_ERROR: | |
1004 | default: | |
1005 | ret_code = LTTNG_ERR_UNK; | |
1006 | break; | |
1007 | } | |
a7a533cd JR |
1008 | goto end; |
1009 | } | |
1010 | ||
159b042f JG |
1011 | DBG("Kernel track %s %d for session id %" PRIu64, |
1012 | lttng_process_attr_to_string(process_attr), | |
1013 | integral_value, session->id); | |
1014 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
1015 | /* | |
1016 | * Maintain a special case for the process ID process attribute | |
1017 | * tracker as it was the only supported attribute prior to 2.12. | |
1018 | */ | |
1019 | ret = kernctl_untrack_pid(session->fd, integral_value); | |
1020 | } else { | |
1021 | ret = kernctl_untrack_id( | |
1022 | session->fd, process_attr, integral_value); | |
1023 | } | |
1024 | if (ret == 0) { | |
1025 | ret_code = LTTNG_OK; | |
1026 | goto end; | |
1027 | } | |
1028 | kernel_wait_quiescent(); | |
1029 | ||
1030 | /* kern-ctl error handling */ | |
1031 | switch (-ret) { | |
1032 | case 0: | |
1033 | ret_code = LTTNG_OK; | |
1034 | break; | |
1035 | case EINVAL: | |
1036 | ret_code = LTTNG_ERR_INVALID; | |
1037 | break; | |
1038 | case ENOMEM: | |
1039 | ret_code = LTTNG_ERR_NOMEM; | |
1040 | break; | |
1041 | case ENOENT: | |
1042 | ret_code = LTTNG_ERR_PROCESS_ATTR_MISSING; | |
1043 | break; | |
1044 | default: | |
1045 | ret_code = LTTNG_ERR_UNK; | |
1046 | break; | |
1047 | } | |
1048 | ||
1049 | /* Attempt to add the value to the tracker. */ | |
1050 | status = process_attr_tracker_inclusion_set_add_value( | |
1051 | tracker, value); | |
1052 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
1053 | ERR("Failed to roll-back the tracking of kernel %s process attribute %d while handling a kern-ctl error", | |
1054 | lttng_process_attr_to_string(process_attr), | |
1055 | integral_value); | |
1056 | } | |
a7a533cd | 1057 | end: |
159b042f | 1058 | return ret_code; |
a5dfbb9d MD |
1059 | } |
1060 | ||
aaf26714 | 1061 | /* |
050349bb DG |
1062 | * Create kernel metadata, open from the kernel tracer and add it to the |
1063 | * kernel session. | |
aaf26714 | 1064 | */ |
a4b92340 | 1065 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
1066 | { |
1067 | int ret; | |
74024a21 | 1068 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 1069 | |
0525e9ae DG |
1070 | assert(session); |
1071 | ||
54012638 | 1072 | /* Allocate kernel metadata */ |
a4b92340 | 1073 | lkm = trace_kernel_create_metadata(); |
54012638 | 1074 | if (lkm == NULL) { |
aaf26714 DG |
1075 | goto error; |
1076 | } | |
1077 | ||
54012638 | 1078 | /* Kernel tracer metadata creation */ |
f3ed775e | 1079 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 1080 | if (ret < 0) { |
74024a21 | 1081 | goto error_open; |
aaf26714 DG |
1082 | } |
1083 | ||
8c0faa1d | 1084 | lkm->fd = ret; |
d40f0359 | 1085 | lkm->key = ++next_kernel_channel_key; |
7b395890 DG |
1086 | /* Prevent fd duplication after execlp() */ |
1087 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
1088 | if (ret < 0) { | |
df0f840b | 1089 | PERROR("fcntl session fd"); |
7b395890 DG |
1090 | } |
1091 | ||
aaf26714 | 1092 | session->metadata = lkm; |
8c0faa1d | 1093 | |
00e2e675 | 1094 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
1095 | |
1096 | return 0; | |
1097 | ||
74024a21 DG |
1098 | error_open: |
1099 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 1100 | error: |
54012638 | 1101 | return -1; |
8c0faa1d DG |
1102 | } |
1103 | ||
1104 | /* | |
050349bb | 1105 | * Start tracing session. |
8c0faa1d DG |
1106 | */ |
1107 | int kernel_start_session(struct ltt_kernel_session *session) | |
1108 | { | |
1109 | int ret; | |
1110 | ||
0525e9ae DG |
1111 | assert(session); |
1112 | ||
8c0faa1d DG |
1113 | ret = kernctl_start_session(session->fd); |
1114 | if (ret < 0) { | |
df0f840b | 1115 | PERROR("ioctl start session"); |
8c0faa1d DG |
1116 | goto error; |
1117 | } | |
1118 | ||
1119 | DBG("Kernel session started"); | |
1120 | ||
1121 | return 0; | |
1122 | ||
1123 | error: | |
1124 | return ret; | |
1125 | } | |
1126 | ||
f3ed775e | 1127 | /* |
050349bb | 1128 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e | 1129 | */ |
7d268848 | 1130 | void kernel_wait_quiescent(void) |
f3ed775e DG |
1131 | { |
1132 | int ret; | |
7d268848 | 1133 | int fd = kernel_tracer_fd; |
f3ed775e DG |
1134 | |
1135 | DBG("Kernel quiescent wait on %d", fd); | |
1136 | ||
1137 | ret = kernctl_wait_quiescent(fd); | |
1138 | if (ret < 0) { | |
df0f840b | 1139 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
1140 | ERR("Kernel quiescent wait failed"); |
1141 | } | |
1142 | } | |
1143 | ||
1144 | /* | |
f3ed775e DG |
1145 | * Force flush buffer of metadata. |
1146 | */ | |
1147 | int kernel_metadata_flush_buffer(int fd) | |
1148 | { | |
1149 | int ret; | |
1150 | ||
169d2cb7 DG |
1151 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
1152 | ||
f3ed775e DG |
1153 | ret = kernctl_buffer_flush(fd); |
1154 | if (ret < 0) { | |
00e2e675 | 1155 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
1156 | } |
1157 | ||
1158 | return 0; | |
1159 | } | |
1160 | ||
1161 | /* | |
050349bb | 1162 | * Force flush buffer for channel. |
f3ed775e DG |
1163 | */ |
1164 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
1165 | { | |
1166 | int ret; | |
1167 | struct ltt_kernel_stream *stream; | |
1168 | ||
0525e9ae DG |
1169 | assert(channel); |
1170 | ||
f3ed775e DG |
1171 | DBG("Flush buffer for channel %s", channel->channel->name); |
1172 | ||
1173 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
1174 | DBG("Flushing channel stream %d", stream->fd); | |
1175 | ret = kernctl_buffer_flush(stream->fd); | |
1176 | if (ret < 0) { | |
df0f840b | 1177 | PERROR("ioctl"); |
f3ed775e DG |
1178 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
1179 | stream->fd, ret); | |
1180 | } | |
1181 | } | |
1182 | ||
1183 | return 0; | |
1184 | } | |
1185 | ||
8c0faa1d | 1186 | /* |
050349bb | 1187 | * Stop tracing session. |
8c0faa1d DG |
1188 | */ |
1189 | int kernel_stop_session(struct ltt_kernel_session *session) | |
1190 | { | |
1191 | int ret; | |
1192 | ||
0525e9ae DG |
1193 | assert(session); |
1194 | ||
8c0faa1d DG |
1195 | ret = kernctl_stop_session(session->fd); |
1196 | if (ret < 0) { | |
1197 | goto error; | |
1198 | } | |
1199 | ||
1200 | DBG("Kernel session stopped"); | |
1201 | ||
1202 | return 0; | |
1203 | ||
1204 | error: | |
1205 | return ret; | |
1206 | } | |
1207 | ||
1208 | /* | |
050349bb DG |
1209 | * Open stream of channel, register it to the kernel tracer and add it |
1210 | * to the stream list of the channel. | |
8c0faa1d | 1211 | * |
1cfb4b98 MD |
1212 | * Note: given that the streams may appear in random order wrt CPU |
1213 | * number (e.g. cpu hotplug), the index value of the stream number in | |
1214 | * the stream name is not necessarily linked to the CPU number. | |
1215 | * | |
050349bb | 1216 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 1217 | */ |
f3ed775e | 1218 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 1219 | { |
1cfb4b98 | 1220 | int ret; |
8c0faa1d DG |
1221 | struct ltt_kernel_stream *lks; |
1222 | ||
0525e9ae DG |
1223 | assert(channel); |
1224 | ||
5a47c6a2 | 1225 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
1226 | lks = trace_kernel_create_stream(channel->channel->name, |
1227 | channel->stream_count); | |
8c0faa1d | 1228 | if (lks == NULL) { |
799e2c4f MD |
1229 | ret = close(ret); |
1230 | if (ret) { | |
1231 | PERROR("close"); | |
1232 | } | |
8c0faa1d DG |
1233 | goto error; |
1234 | } | |
1235 | ||
1236 | lks->fd = ret; | |
7b395890 DG |
1237 | /* Prevent fd duplication after execlp() */ |
1238 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
1239 | if (ret < 0) { | |
df0f840b | 1240 | PERROR("fcntl session fd"); |
7b395890 DG |
1241 | } |
1242 | ||
1624d5b7 JD |
1243 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
1244 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
1245 | ||
1cfb4b98 | 1246 | /* Add stream to channel stream list */ |
8c0faa1d DG |
1247 | cds_list_add(&lks->list, &channel->stream_list.head); |
1248 | channel->stream_count++; | |
8c0faa1d | 1249 | |
00e2e675 DG |
1250 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
1251 | lks->state); | |
54012638 | 1252 | } |
8c0faa1d DG |
1253 | |
1254 | return channel->stream_count; | |
1255 | ||
1256 | error: | |
54012638 | 1257 | return -1; |
8c0faa1d DG |
1258 | } |
1259 | ||
1260 | /* | |
050349bb | 1261 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 1262 | */ |
f3ed775e | 1263 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
1264 | { |
1265 | int ret; | |
1266 | ||
0525e9ae DG |
1267 | assert(session); |
1268 | ||
8c0faa1d DG |
1269 | ret = kernctl_create_stream(session->metadata->fd); |
1270 | if (ret < 0) { | |
df0f840b | 1271 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
1272 | goto error; |
1273 | } | |
1274 | ||
1275 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
1276 | session->metadata_stream_fd = ret; | |
7b395890 DG |
1277 | /* Prevent fd duplication after execlp() */ |
1278 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
1279 | if (ret < 0) { | |
df0f840b | 1280 | PERROR("fcntl session fd"); |
7b395890 | 1281 | } |
aaf26714 DG |
1282 | |
1283 | return 0; | |
1284 | ||
1285 | error: | |
54012638 | 1286 | return -1; |
aaf26714 | 1287 | } |
2ef84c95 DG |
1288 | |
1289 | /* | |
9f19cc17 | 1290 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 1291 | */ |
7d268848 | 1292 | ssize_t kernel_list_events(struct lttng_event **events) |
2ef84c95 | 1293 | { |
53efb85a | 1294 | int fd, ret; |
9f19cc17 DG |
1295 | char *event; |
1296 | size_t nbmem, count = 0; | |
2ef84c95 | 1297 | FILE *fp; |
9f19cc17 | 1298 | struct lttng_event *elist; |
2ef84c95 | 1299 | |
0525e9ae DG |
1300 | assert(events); |
1301 | ||
7d268848 | 1302 | fd = kernctl_tracepoint_list(kernel_tracer_fd); |
2ef84c95 | 1303 | if (fd < 0) { |
df0f840b | 1304 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
1305 | goto error; |
1306 | } | |
1307 | ||
1308 | fp = fdopen(fd, "r"); | |
1309 | if (fp == NULL) { | |
df0f840b | 1310 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 1311 | goto error_fp; |
2ef84c95 DG |
1312 | } |
1313 | ||
1314 | /* | |
1315 | * Init memory size counter | |
1316 | * See kernel-ctl.h for explanation of this value | |
1317 | */ | |
6725fe19 | 1318 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
ba7f0ae5 | 1319 | elist = zmalloc(sizeof(struct lttng_event) * nbmem); |
3b870559 MD |
1320 | if (elist == NULL) { |
1321 | PERROR("alloc list events"); | |
1322 | count = -ENOMEM; | |
1323 | goto end; | |
1324 | } | |
2ef84c95 | 1325 | |
53efb85a | 1326 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 1327 | if (count >= nbmem) { |
3b870559 | 1328 | struct lttng_event *new_elist; |
53efb85a | 1329 | size_t new_nbmem; |
3b870559 | 1330 | |
53efb85a MD |
1331 | new_nbmem = nbmem << 1; |
1332 | DBG("Reallocating event list from %zu to %zu bytes", | |
1333 | nbmem, new_nbmem); | |
1334 | new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event)); | |
3b870559 | 1335 | if (new_elist == NULL) { |
df0f840b | 1336 | PERROR("realloc list events"); |
3b870559 MD |
1337 | free(event); |
1338 | free(elist); | |
61b73b12 MD |
1339 | count = -ENOMEM; |
1340 | goto end; | |
2ef84c95 | 1341 | } |
53efb85a MD |
1342 | /* Zero the new memory */ |
1343 | memset(new_elist + nbmem, 0, | |
1344 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
1345 | nbmem = new_nbmem; | |
3b870559 | 1346 | elist = new_elist; |
2ef84c95 | 1347 | } |
99497cd0 MD |
1348 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
1349 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 1350 | elist[count].enabled = -1; |
9f19cc17 | 1351 | count++; |
3b870559 | 1352 | free(event); |
2ef84c95 DG |
1353 | } |
1354 | ||
9f19cc17 | 1355 | *events = elist; |
ced2f820 | 1356 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 1357 | end: |
799e2c4f MD |
1358 | ret = fclose(fp); /* closes both fp and fd */ |
1359 | if (ret) { | |
1360 | PERROR("fclose"); | |
1361 | } | |
9f19cc17 | 1362 | return count; |
2ef84c95 | 1363 | |
61b73b12 | 1364 | error_fp: |
799e2c4f MD |
1365 | ret = close(fd); |
1366 | if (ret) { | |
1367 | PERROR("close"); | |
1368 | } | |
2ef84c95 DG |
1369 | error: |
1370 | return -1; | |
1371 | } | |
096102bd DG |
1372 | |
1373 | /* | |
1374 | * Get kernel version and validate it. | |
1375 | */ | |
7d268848 | 1376 | int kernel_validate_version(struct lttng_kernel_tracer_version *version, |
88076e89 | 1377 | struct lttng_kernel_tracer_abi_version *abi_version) |
096102bd DG |
1378 | { |
1379 | int ret; | |
096102bd | 1380 | |
7d268848 | 1381 | ret = kernctl_tracer_version(kernel_tracer_fd, version); |
096102bd | 1382 | if (ret < 0) { |
521dd134 | 1383 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
1384 | goto error; |
1385 | } | |
1386 | ||
1387 | /* Validate version */ | |
88076e89 | 1388 | if (version->major != VERSION_MAJOR) { |
c052142c | 1389 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", |
88076e89 | 1390 | version->major, VERSION_MAJOR); |
096102bd | 1391 | goto error_version; |
096102bd | 1392 | } |
7d268848 | 1393 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, abi_version); |
c052142c | 1394 | if (ret < 0) { |
521dd134 | 1395 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
1396 | goto error; |
1397 | } | |
88076e89 | 1398 | if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) { |
521dd134 | 1399 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
88076e89 | 1400 | abi_version->major, abi_version->minor, |
c052142c MD |
1401 | LTTNG_MODULES_ABI_MAJOR_VERSION); |
1402 | goto error; | |
1403 | } | |
1404 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
88076e89 JD |
1405 | version->major, version->minor, |
1406 | abi_version->major, abi_version->minor); | |
096102bd DG |
1407 | return 0; |
1408 | ||
1409 | error_version: | |
096102bd DG |
1410 | ret = -1; |
1411 | ||
1412 | error: | |
521dd134 | 1413 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
1414 | return ret; |
1415 | } | |
335a95b7 MD |
1416 | |
1417 | /* | |
1418 | * Kernel work-arounds called at the start of sessiond main(). | |
1419 | */ | |
1420 | int init_kernel_workarounds(void) | |
1421 | { | |
8936c33a | 1422 | int ret; |
335a95b7 MD |
1423 | FILE *fp; |
1424 | ||
1425 | /* | |
1426 | * boot_id needs to be read once before being used concurrently | |
1427 | * to deal with a Linux kernel race. A fix is proposed for | |
1428 | * upstream, but the work-around is needed for older kernels. | |
1429 | */ | |
1430 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
1431 | if (!fp) { | |
1432 | goto end_boot_id; | |
1433 | } | |
1434 | while (!feof(fp)) { | |
1435 | char buf[37] = ""; | |
1436 | ||
8936c33a DG |
1437 | ret = fread(buf, 1, sizeof(buf), fp); |
1438 | if (ret < 0) { | |
1439 | /* Ignore error, we don't really care */ | |
1440 | } | |
335a95b7 | 1441 | } |
799e2c4f MD |
1442 | ret = fclose(fp); |
1443 | if (ret) { | |
1444 | PERROR("fclose"); | |
1445 | } | |
335a95b7 | 1446 | end_boot_id: |
335a95b7 MD |
1447 | return 0; |
1448 | } | |
2f77fc4b DG |
1449 | |
1450 | /* | |
d070c424 | 1451 | * Teardown of a kernel session, keeping data required by destroy notifiers. |
2f77fc4b DG |
1452 | */ |
1453 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
1454 | { | |
82b69413 JG |
1455 | struct lttng_trace_chunk *trace_chunk; |
1456 | ||
2f77fc4b DG |
1457 | if (ksess == NULL) { |
1458 | DBG3("No kernel session when tearing down session"); | |
1459 | return; | |
1460 | } | |
1461 | ||
1462 | DBG("Tearing down kernel session"); | |
82b69413 | 1463 | trace_chunk = ksess->current_trace_chunk; |
2f77fc4b | 1464 | |
07b86b52 | 1465 | /* |
15dc512a DG |
1466 | * Destroy channels on the consumer if at least one FD has been sent and we |
1467 | * are in no output mode because the streams are in *no* monitor mode so we | |
1468 | * have to send a command to clean them up or else they leaked. | |
07b86b52 | 1469 | */ |
15dc512a | 1470 | if (!ksess->output_traces && ksess->consumer_fds_sent) { |
07b86b52 JD |
1471 | int ret; |
1472 | struct consumer_socket *socket; | |
1473 | struct lttng_ht_iter iter; | |
1474 | ||
1475 | /* For each consumer socket. */ | |
d069d577 | 1476 | rcu_read_lock(); |
07b86b52 JD |
1477 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, |
1478 | socket, node.node) { | |
1479 | struct ltt_kernel_channel *chan; | |
1480 | ||
1481 | /* For each channel, ask the consumer to destroy it. */ | |
1482 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1483 | ret = kernel_consumer_destroy_channel(socket, chan); | |
1484 | if (ret < 0) { | |
1485 | /* Consumer is probably dead. Use next socket. */ | |
1486 | continue; | |
1487 | } | |
1488 | } | |
1489 | } | |
d069d577 | 1490 | rcu_read_unlock(); |
07b86b52 JD |
1491 | } |
1492 | ||
2f77fc4b DG |
1493 | /* Close any relayd session */ |
1494 | consumer_output_send_destroy_relayd(ksess->consumer); | |
1495 | ||
1496 | trace_kernel_destroy_session(ksess); | |
82b69413 | 1497 | lttng_trace_chunk_put(trace_chunk); |
2f77fc4b | 1498 | } |
fb5f35b6 | 1499 | |
d070c424 MD |
1500 | /* Teardown of data required by destroy notifiers. */ |
1501 | void kernel_free_session(struct ltt_kernel_session *ksess) | |
1502 | { | |
1503 | if (ksess == NULL) { | |
1504 | return; | |
1505 | } | |
1506 | trace_kernel_free_session(ksess); | |
1507 | } | |
1508 | ||
fb5f35b6 DG |
1509 | /* |
1510 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
1511 | */ | |
1512 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
1513 | { | |
1514 | struct ltt_kernel_session *ksess = NULL; | |
1515 | ||
1516 | assert(kchan); | |
1517 | assert(kchan->channel); | |
1518 | ||
1519 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
1520 | ||
1521 | /* Update channel count of associated session. */ | |
1522 | if (kchan->session) { | |
1523 | /* Keep pointer reference so we can update it after the destroy. */ | |
1524 | ksess = kchan->session; | |
1525 | } | |
1526 | ||
1527 | trace_kernel_destroy_channel(kchan); | |
1528 | ||
1529 | /* | |
1530 | * At this point the kernel channel is not visible anymore. This is safe | |
1531 | * since in order to work on a visible kernel session, the tracing session | |
1532 | * lock (ltt_session.lock) MUST be acquired. | |
1533 | */ | |
1534 | if (ksess) { | |
1535 | ksess->channel_count--; | |
1536 | } | |
1537 | } | |
6dc3064a DG |
1538 | |
1539 | /* | |
1540 | * Take a snapshot for a given kernel session. | |
1541 | * | |
9a654598 | 1542 | * Return LTTNG_OK on success or else return a LTTNG_ERR code. |
6dc3064a | 1543 | */ |
fb9a95c4 JG |
1544 | enum lttng_error_code kernel_snapshot_record( |
1545 | struct ltt_kernel_session *ksess, | |
348a81dc | 1546 | const struct consumer_output *output, int wait, |
d07ceecd | 1547 | uint64_t nb_packets_per_stream) |
6dc3064a | 1548 | { |
2a06df8d | 1549 | int err, ret, saved_metadata_fd; |
9a654598 | 1550 | enum lttng_error_code status = LTTNG_OK; |
6dc3064a DG |
1551 | struct consumer_socket *socket; |
1552 | struct lttng_ht_iter iter; | |
1553 | struct ltt_kernel_metadata *saved_metadata; | |
3b967712 | 1554 | char *trace_path = NULL; |
5da88b0f | 1555 | size_t consumer_path_offset = 0; |
6dc3064a DG |
1556 | |
1557 | assert(ksess); | |
1558 | assert(ksess->consumer); | |
1559 | assert(output); | |
1560 | ||
1561 | DBG("Kernel snapshot record started"); | |
1562 | ||
1563 | /* Save current metadata since the following calls will change it. */ | |
1564 | saved_metadata = ksess->metadata; | |
1565 | saved_metadata_fd = ksess->metadata_stream_fd; | |
1566 | ||
1567 | rcu_read_lock(); | |
1568 | ||
1569 | ret = kernel_open_metadata(ksess); | |
1570 | if (ret < 0) { | |
9a654598 | 1571 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1572 | goto error; |
1573 | } | |
1574 | ||
1575 | ret = kernel_open_metadata_stream(ksess); | |
1576 | if (ret < 0) { | |
9a654598 | 1577 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1578 | goto error_open_stream; |
1579 | } | |
1580 | ||
3b967712 | 1581 | trace_path = setup_channel_trace_path(ksess->consumer, |
5da88b0f | 1582 | DEFAULT_KERNEL_TRACE_DIR, &consumer_path_offset); |
3b967712 MD |
1583 | if (!trace_path) { |
1584 | status = LTTNG_ERR_INVALID; | |
1585 | goto error; | |
1586 | } | |
6dc3064a | 1587 | /* Send metadata to consumer and snapshot everything. */ |
348a81dc | 1588 | cds_lfht_for_each_entry(output->socks->ht, &iter.iter, |
6dc3064a | 1589 | socket, node.node) { |
6dc3064a | 1590 | struct ltt_kernel_channel *chan; |
6dc3064a | 1591 | |
6dc3064a DG |
1592 | pthread_mutex_lock(socket->lock); |
1593 | /* This stream must not be monitored by the consumer. */ | |
07b86b52 | 1594 | ret = kernel_consumer_add_metadata(socket, ksess, 0); |
6dc3064a | 1595 | pthread_mutex_unlock(socket->lock); |
6dc3064a | 1596 | if (ret < 0) { |
0ed78e50 | 1597 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1598 | goto error_consumer; |
1599 | } | |
1600 | ||
1601 | /* For each channel, ask the consumer to snapshot it. */ | |
1602 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
9a654598 | 1603 | status = consumer_snapshot_channel(socket, chan->key, output, 0, |
5c786ded | 1604 | ksess->uid, ksess->gid, |
5da88b0f | 1605 | &trace_path[consumer_path_offset], wait, |
d2956687 | 1606 | nb_packets_per_stream); |
9a654598 | 1607 | if (status != LTTNG_OK) { |
2a06df8d DG |
1608 | (void) kernel_consumer_destroy_metadata(socket, |
1609 | ksess->metadata); | |
6dc3064a DG |
1610 | goto error_consumer; |
1611 | } | |
1612 | } | |
1613 | ||
1614 | /* Snapshot metadata, */ | |
9a654598 | 1615 | status = consumer_snapshot_channel(socket, ksess->metadata->key, output, |
5da88b0f MD |
1616 | 1, ksess->uid, ksess->gid, &trace_path[consumer_path_offset], |
1617 | wait, 0); | |
9a654598 | 1618 | if (status != LTTNG_OK) { |
6dc3064a DG |
1619 | goto error_consumer; |
1620 | } | |
07b86b52 JD |
1621 | |
1622 | /* | |
1623 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1624 | * it's not monitored on the consumer side. | |
1625 | */ | |
1626 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1627 | } |
1628 | ||
1629 | error_consumer: | |
1630 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1631 | err = close(ksess->metadata_stream_fd); |
1632 | if (err < 0) { | |
6dc3064a DG |
1633 | PERROR("close snapshot kernel"); |
1634 | } | |
1635 | ||
1636 | error_open_stream: | |
1637 | trace_kernel_destroy_metadata(ksess->metadata); | |
1638 | error: | |
1639 | /* Restore metadata state.*/ | |
1640 | ksess->metadata = saved_metadata; | |
1641 | ksess->metadata_stream_fd = saved_metadata_fd; | |
6dc3064a | 1642 | rcu_read_unlock(); |
3b967712 | 1643 | free(trace_path); |
9a654598 | 1644 | return status; |
6dc3064a | 1645 | } |
834978fd DG |
1646 | |
1647 | /* | |
1648 | * Get the syscall mask array from the kernel tracer. | |
1649 | * | |
1650 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1651 | * be freed. | |
1652 | */ | |
1653 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1654 | { | |
1655 | assert(syscall_mask); | |
1656 | assert(nr_bits); | |
1657 | ||
1658 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1659 | } | |
6e21424e | 1660 | |
959e3c66 JR |
1661 | static |
1662 | int kernel_tracer_abi_greater_or_equal(unsigned int major, unsigned int minor) | |
6e21424e | 1663 | { |
959e3c66 | 1664 | int ret; |
6e21424e JR |
1665 | struct lttng_kernel_tracer_abi_version abi; |
1666 | ||
7d268848 | 1667 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, &abi); |
6e21424e JR |
1668 | if (ret < 0) { |
1669 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1670 | goto error; | |
1671 | } | |
1672 | ||
959e3c66 JR |
1673 | ret = abi.major > major || (abi.major == major && abi.minor >= minor); |
1674 | error: | |
1675 | return ret; | |
1676 | } | |
1677 | ||
1678 | /* | |
1679 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1680 | * version number. | |
1681 | * | |
1682 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1683 | * of errors. | |
1684 | */ | |
1685 | int kernel_supports_ring_buffer_snapshot_sample_positions(void) | |
1686 | { | |
6e21424e JR |
1687 | /* |
1688 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1689 | */ | |
959e3c66 | 1690 | return kernel_tracer_abi_greater_or_equal(2, 3); |
6e21424e | 1691 | } |
5c408ad8 | 1692 | |
a40a503f MD |
1693 | /* |
1694 | * Check for the support of the packet sequence number via abi version number. | |
1695 | * | |
1696 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1697 | * of errors. | |
1698 | */ | |
1699 | int kernel_supports_ring_buffer_packet_sequence_number(void) | |
1700 | { | |
a40a503f | 1701 | /* |
3029bc92 JG |
1702 | * Packet sequence number was introduced in LTTng 2.8, |
1703 | * lttng-modules ABI 2.1. | |
a40a503f | 1704 | */ |
959e3c66 JR |
1705 | return kernel_tracer_abi_greater_or_equal(2, 1); |
1706 | } | |
1707 | ||
1708 | /* | |
1709 | * Check for the support of event notifiers via abi version number. | |
1710 | * | |
1711 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1712 | * of errors. | |
1713 | */ | |
1714 | int kernel_supports_event_notifiers(void) | |
1715 | { | |
1716 | /* | |
1717 | * Event notifiers were introduced in LTTng 2.13, lttng-modules ABI 2.6. | |
1718 | */ | |
1719 | return kernel_tracer_abi_greater_or_equal(2, 6); | |
a40a503f MD |
1720 | } |
1721 | ||
5c408ad8 JD |
1722 | /* |
1723 | * Rotate a kernel session. | |
1724 | * | |
d5a1b7aa | 1725 | * Return LTTNG_OK on success or else an LTTng error code. |
5c408ad8 | 1726 | */ |
d5a1b7aa | 1727 | enum lttng_error_code kernel_rotate_session(struct ltt_session *session) |
5c408ad8 JD |
1728 | { |
1729 | int ret; | |
d5a1b7aa | 1730 | enum lttng_error_code status = LTTNG_OK; |
5c408ad8 JD |
1731 | struct consumer_socket *socket; |
1732 | struct lttng_ht_iter iter; | |
1733 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1734 | ||
1735 | assert(ksess); | |
1736 | assert(ksess->consumer); | |
1737 | ||
1738 | DBG("Rotate kernel session %s started (session %" PRIu64 ")", | |
1739 | session->name, session->id); | |
1740 | ||
1741 | rcu_read_lock(); | |
1742 | ||
1743 | /* | |
1744 | * Note that this loop will end after one iteration given that there is | |
1745 | * only one kernel consumer. | |
1746 | */ | |
1747 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1748 | socket, node.node) { | |
1749 | struct ltt_kernel_channel *chan; | |
1750 | ||
b8a1b0bd | 1751 | /* For each channel, ask the consumer to rotate it. */ |
5c408ad8 | 1752 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { |
92816cc3 JG |
1753 | DBG("Rotate kernel channel %" PRIu64 ", session %s", |
1754 | chan->key, session->name); | |
5c408ad8 JD |
1755 | ret = consumer_rotate_channel(socket, chan->key, |
1756 | ksess->uid, ksess->gid, ksess->consumer, | |
d2956687 | 1757 | /* is_metadata_channel */ false); |
5c408ad8 | 1758 | if (ret < 0) { |
7e0de219 | 1759 | status = LTTNG_ERR_ROTATION_FAIL_CONSUMER; |
5c408ad8 JD |
1760 | goto error; |
1761 | } | |
1762 | } | |
1763 | ||
1764 | /* | |
1765 | * Rotate the metadata channel. | |
1766 | */ | |
22a1b931 | 1767 | ret = consumer_rotate_channel(socket, ksess->metadata->key, |
5c408ad8 | 1768 | ksess->uid, ksess->gid, ksess->consumer, |
d2956687 | 1769 | /* is_metadata_channel */ true); |
5c408ad8 | 1770 | if (ret < 0) { |
7e0de219 | 1771 | status = LTTNG_ERR_ROTATION_FAIL_CONSUMER; |
5c408ad8 JD |
1772 | goto error; |
1773 | } | |
1774 | } | |
1775 | ||
5c408ad8 JD |
1776 | error: |
1777 | rcu_read_unlock(); | |
d5a1b7aa | 1778 | return status; |
5c408ad8 | 1779 | } |
d2956687 JG |
1780 | |
1781 | enum lttng_error_code kernel_create_channel_subdirectories( | |
1782 | const struct ltt_kernel_session *ksess) | |
1783 | { | |
1784 | enum lttng_error_code ret = LTTNG_OK; | |
1785 | enum lttng_trace_chunk_status chunk_status; | |
1786 | ||
1787 | rcu_read_lock(); | |
1788 | assert(ksess->current_trace_chunk); | |
1789 | ||
1790 | /* | |
1791 | * Create the index subdirectory which will take care | |
1792 | * of implicitly creating the channel's path. | |
1793 | */ | |
1794 | chunk_status = lttng_trace_chunk_create_subdirectory( | |
1795 | ksess->current_trace_chunk, | |
1796 | DEFAULT_KERNEL_TRACE_DIR "/" DEFAULT_INDEX_DIR); | |
1797 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { | |
1798 | ret = LTTNG_ERR_CREATE_DIR_FAIL; | |
1799 | goto error; | |
1800 | } | |
1801 | error: | |
1802 | rcu_read_unlock(); | |
1803 | return ret; | |
1804 | } | |
7d268848 MD |
1805 | |
1806 | /* | |
1807 | * Setup necessary data for kernel tracer action. | |
1808 | */ | |
1809 | LTTNG_HIDDEN | |
1810 | int init_kernel_tracer(void) | |
1811 | { | |
1812 | int ret; | |
1813 | bool is_root = !getuid(); | |
1814 | ||
1815 | /* Modprobe lttng kernel modules */ | |
1816 | ret = modprobe_lttng_control(); | |
1817 | if (ret < 0) { | |
1818 | goto error; | |
1819 | } | |
1820 | ||
1821 | /* Open debugfs lttng */ | |
1822 | kernel_tracer_fd = open(module_proc_lttng, O_RDWR); | |
1823 | if (kernel_tracer_fd < 0) { | |
1824 | DBG("Failed to open %s", module_proc_lttng); | |
1825 | goto error_open; | |
1826 | } | |
1827 | ||
1828 | /* Validate kernel version */ | |
1829 | ret = kernel_validate_version(&kernel_tracer_version, | |
1830 | &kernel_tracer_abi_version); | |
1831 | if (ret < 0) { | |
1832 | goto error_version; | |
1833 | } | |
1834 | ||
1835 | ret = modprobe_lttng_data(); | |
1836 | if (ret < 0) { | |
1837 | goto error_modules; | |
1838 | } | |
1839 | ||
1840 | ret = kernel_supports_ring_buffer_snapshot_sample_positions(); | |
1841 | if (ret < 0) { | |
1842 | goto error_modules; | |
1843 | } | |
1844 | ||
1845 | if (ret < 1) { | |
1846 | WARN("Kernel tracer does not support buffer monitoring. " | |
1847 | "The monitoring timer of channels in the kernel domain " | |
1848 | "will be set to 0 (disabled)."); | |
1849 | } | |
1850 | ||
1851 | DBG("Kernel tracer fd %d", kernel_tracer_fd); | |
1852 | ||
1853 | ret = syscall_init_table(kernel_tracer_fd); | |
1854 | if (ret < 0) { | |
1855 | ERR("Unable to populate syscall table. Syscall tracing won't " | |
1856 | "work for this session daemon."); | |
1857 | } | |
1858 | return 0; | |
1859 | ||
1860 | error_version: | |
1861 | modprobe_remove_lttng_control(); | |
1862 | ret = close(kernel_tracer_fd); | |
1863 | if (ret) { | |
1864 | PERROR("close"); | |
1865 | } | |
1866 | kernel_tracer_fd = -1; | |
1867 | return LTTNG_ERR_KERN_VERSION; | |
1868 | ||
1869 | error_modules: | |
1870 | ret = close(kernel_tracer_fd); | |
1871 | if (ret) { | |
1872 | PERROR("close"); | |
1873 | } | |
1874 | ||
1875 | error_open: | |
1876 | modprobe_remove_lttng_control(); | |
1877 | ||
1878 | error: | |
1879 | WARN("No kernel tracer available"); | |
1880 | kernel_tracer_fd = -1; | |
1881 | if (!is_root) { | |
1882 | return LTTNG_ERR_NEED_ROOT_SESSIOND; | |
1883 | } else { | |
1884 | return LTTNG_ERR_KERN_NA; | |
1885 | } | |
1886 | } | |
1887 | ||
1888 | LTTNG_HIDDEN | |
1889 | void cleanup_kernel_tracer(void) | |
1890 | { | |
1891 | int ret; | |
1892 | ||
1893 | DBG2("Closing kernel fd"); | |
1894 | if (kernel_tracer_fd >= 0) { | |
1895 | ret = close(kernel_tracer_fd); | |
1896 | if (ret) { | |
1897 | PERROR("close"); | |
1898 | } | |
1899 | kernel_tracer_fd = -1; | |
1900 | } | |
1901 | DBG("Unloading kernel modules"); | |
1902 | modprobe_remove_lttng_all(); | |
1903 | free(syscall_table); | |
1904 | } | |
1905 | ||
1906 | LTTNG_HIDDEN | |
1907 | bool kernel_tracer_is_initialized(void) | |
1908 | { | |
1909 | return kernel_tracer_fd >= 0; | |
1910 | } | |
bca212a2 MD |
1911 | |
1912 | /* | |
1913 | * Clear a kernel session. | |
1914 | * | |
1915 | * Return LTTNG_OK on success or else an LTTng error code. | |
1916 | */ | |
1917 | enum lttng_error_code kernel_clear_session(struct ltt_session *session) | |
1918 | { | |
1919 | int ret; | |
1920 | enum lttng_error_code status = LTTNG_OK; | |
1921 | struct consumer_socket *socket; | |
1922 | struct lttng_ht_iter iter; | |
1923 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1924 | ||
1925 | assert(ksess); | |
1926 | assert(ksess->consumer); | |
1927 | ||
1928 | DBG("Clear kernel session %s (session %" PRIu64 ")", | |
1929 | session->name, session->id); | |
1930 | ||
1931 | rcu_read_lock(); | |
1932 | ||
1933 | if (ksess->active) { | |
1934 | ERR("Expecting inactive session %s (%" PRIu64 ")", session->name, session->id); | |
1935 | status = LTTNG_ERR_FATAL; | |
1936 | goto end; | |
1937 | } | |
1938 | ||
1939 | /* | |
1940 | * Note that this loop will end after one iteration given that there is | |
1941 | * only one kernel consumer. | |
1942 | */ | |
1943 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1944 | socket, node.node) { | |
1945 | struct ltt_kernel_channel *chan; | |
1946 | ||
1947 | /* For each channel, ask the consumer to clear it. */ | |
1948 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1949 | DBG("Clear kernel channel %" PRIu64 ", session %s", | |
1950 | chan->key, session->name); | |
1951 | ret = consumer_clear_channel(socket, chan->key); | |
1952 | if (ret < 0) { | |
1953 | goto error; | |
1954 | } | |
1955 | } | |
1956 | ||
1957 | if (!ksess->metadata) { | |
1958 | /* | |
1959 | * Nothing to do for the metadata. | |
1960 | * This is a snapshot session. | |
1961 | * The metadata is genererated on the fly. | |
1962 | */ | |
1963 | continue; | |
1964 | } | |
1965 | ||
1966 | /* | |
1967 | * Clear the metadata channel. | |
1968 | * Metadata channel is not cleared per se but we still need to | |
1969 | * perform a rotation operation on it behind the scene. | |
1970 | */ | |
1971 | ret = consumer_clear_channel(socket, ksess->metadata->key); | |
1972 | if (ret < 0) { | |
1973 | goto error; | |
1974 | } | |
1975 | } | |
1976 | ||
1977 | goto end; | |
1978 | error: | |
1979 | switch (-ret) { | |
1980 | case LTTCOMM_CONSUMERD_RELAYD_CLEAR_DISALLOWED: | |
1981 | status = LTTNG_ERR_CLEAR_RELAY_DISALLOWED; | |
1982 | break; | |
1983 | default: | |
1984 | status = LTTNG_ERR_CLEAR_FAIL_CONSUMER; | |
1985 | break; | |
1986 | } | |
1987 | end: | |
1988 | rcu_read_unlock(); | |
1989 | return status; | |
1990 | } |