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