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> |
352b58f5 | 18 | #include <common/hashtable/utils.h> |
82b69413 | 19 | #include <common/trace-chunk.h> |
db758600 | 20 | #include <common/kernel-ctl/kernel-ctl.h> |
c052142c | 21 | #include <common/kernel-ctl/kernel-ioctl.h> |
42224349 | 22 | #include <common/sessiond-comm/sessiond-comm.h> |
c5bf436c JG |
23 | #include <common/tracker.h> |
24 | #include <common/utils.h> | |
25 | #include <lttng/event.h> | |
26 | #include <lttng/lttng-error.h> | |
27 | #include <lttng/tracker.h> | |
1e307fab | 28 | |
352b58f5 JR |
29 | #include <lttng/userspace-probe.h> |
30 | #include <lttng/userspace-probe-internal.h> | |
31 | #include <lttng/condition/event-rule.h> | |
32 | #include <lttng/condition/event-rule-internal.h> | |
33 | #include <lttng/event-rule/event-rule.h> | |
34 | #include <lttng/event-rule/event-rule-internal.h> | |
35 | #include <lttng/event-rule/uprobe-internal.h> | |
36 | ||
7d268848 MD |
37 | #include "lttng-sessiond.h" |
38 | #include "lttng-syscall.h" | |
352b58f5 | 39 | #include "condition-internal.h" |
2f77fc4b | 40 | #include "consumer.h" |
4771f025 | 41 | #include "kernel.h" |
6dc3064a | 42 | #include "kernel-consumer.h" |
096102bd | 43 | #include "kern-modules.h" |
834978fd | 44 | #include "utils.h" |
5c408ad8 | 45 | #include "rotate.h" |
7d268848 | 46 | #include "modprobe.h" |
c5bf436c | 47 | #include "tracker.h" |
352b58f5 | 48 | #include "notification-thread-commands.h" |
20fe2104 | 49 | |
e1f3997a JD |
50 | /* |
51 | * Key used to reference a channel between the sessiond and the consumer. This | |
52 | * is only read and updated with the session_list lock held. | |
53 | */ | |
54 | static uint64_t next_kernel_channel_key; | |
55 | ||
7d268848 MD |
56 | static const char *module_proc_lttng = "/proc/lttng"; |
57 | ||
58 | static int kernel_tracer_fd = -1; | |
352b58f5 JR |
59 | static int kernel_tracer_event_notifier_group_fd = -1; |
60 | static int kernel_tracer_event_notifier_group_notification_fd = -1; | |
61 | static struct cds_lfht *kernel_token_to_event_notifier_rule_ht; | |
7d268848 | 62 | |
d65106b1 | 63 | /* |
050349bb | 64 | * Add context on a kernel channel. |
df3c77c8 JG |
65 | * |
66 | * Assumes the ownership of ctx. | |
d65106b1 DG |
67 | */ |
68 | int kernel_add_channel_context(struct ltt_kernel_channel *chan, | |
645328ae | 69 | struct ltt_kernel_context *ctx) |
d65106b1 DG |
70 | { |
71 | int ret; | |
72 | ||
0525e9ae DG |
73 | assert(chan); |
74 | assert(ctx); | |
75 | ||
d65106b1 | 76 | DBG("Adding context to channel %s", chan->channel->name); |
645328ae | 77 | ret = kernctl_add_context(chan->fd, &ctx->ctx); |
d65106b1 | 78 | if (ret < 0) { |
32af2c95 | 79 | switch (-ret) { |
1ae5e83e JD |
80 | case ENOSYS: |
81 | /* Exists but not available for this kernel */ | |
82 | ret = LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE; | |
83 | goto error; | |
84 | case EEXIST: | |
b579acd9 DG |
85 | /* If EEXIST, we just ignore the error */ |
86 | ret = 0; | |
1ae5e83e JD |
87 | goto end; |
88 | default: | |
89 | PERROR("add context ioctl"); | |
90 | ret = LTTNG_ERR_KERN_CONTEXT_FAIL; | |
91 | goto error; | |
b579acd9 | 92 | } |
d65106b1 | 93 | } |
21ed98c1 | 94 | ret = 0; |
d65106b1 | 95 | |
1ae5e83e | 96 | end: |
645328ae | 97 | cds_list_add_tail(&ctx->list, &chan->ctx_list); |
ba985c3a | 98 | ctx->in_list = true; |
df3c77c8 | 99 | ctx = NULL; |
d65106b1 | 100 | error: |
df3c77c8 JG |
101 | if (ctx) { |
102 | trace_kernel_destroy_context(ctx); | |
103 | } | |
d65106b1 DG |
104 | return ret; |
105 | } | |
106 | ||
20fe2104 | 107 | /* |
050349bb DG |
108 | * Create a new kernel session, register it to the kernel tracer and add it to |
109 | * the session daemon session. | |
20fe2104 | 110 | */ |
7d268848 | 111 | int kernel_create_session(struct ltt_session *session) |
20fe2104 DG |
112 | { |
113 | int ret; | |
114 | struct ltt_kernel_session *lks; | |
115 | ||
0525e9ae DG |
116 | assert(session); |
117 | ||
54012638 | 118 | /* Allocate data structure */ |
dec56f6c | 119 | lks = trace_kernel_create_session(); |
20fe2104 | 120 | if (lks == NULL) { |
54012638 | 121 | ret = -1; |
20fe2104 DG |
122 | goto error; |
123 | } | |
124 | ||
54012638 | 125 | /* Kernel tracer session creation */ |
7d268848 | 126 | ret = kernctl_create_session(kernel_tracer_fd); |
20fe2104 | 127 | if (ret < 0) { |
df0f840b | 128 | PERROR("ioctl kernel create session"); |
20fe2104 DG |
129 | goto error; |
130 | } | |
131 | ||
20fe2104 | 132 | lks->fd = ret; |
7b395890 DG |
133 | /* Prevent fd duplication after execlp() */ |
134 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
135 | if (ret < 0) { | |
df0f840b | 136 | PERROR("fcntl session fd"); |
7b395890 DG |
137 | } |
138 | ||
53632229 | 139 | lks->id = session->id; |
3bd1e081 | 140 | lks->consumer_fds_sent = 0; |
8c0faa1d | 141 | session->kernel_session = lks; |
8c0faa1d DG |
142 | |
143 | DBG("Kernel session created (fd: %d)", lks->fd); | |
20fe2104 | 144 | |
8ff4109e JR |
145 | /* |
146 | * This is necessary since the creation time is present in the session | |
147 | * name when it is generated. | |
148 | */ | |
149 | if (session->has_auto_generated_name) { | |
150 | ret = kernctl_session_set_name(lks->fd, DEFAULT_SESSION_NAME); | |
151 | } else { | |
152 | ret = kernctl_session_set_name(lks->fd, session->name); | |
153 | } | |
154 | if (ret) { | |
155 | WARN("Could not set kernel session name for session %" PRIu64 " name: %s", | |
156 | session->id, session->name); | |
157 | } | |
158 | ||
e04b2181 JR |
159 | ret = kernctl_session_set_creation_time(lks->fd, session->creation_time); |
160 | if (ret) { | |
161 | WARN("Could not set kernel session creation time for session %" PRIu64 " name: %s", | |
162 | session->id, session->name); | |
163 | } | |
164 | ||
20fe2104 DG |
165 | return 0; |
166 | ||
167 | error: | |
5f62c685 DG |
168 | if (lks) { |
169 | trace_kernel_destroy_session(lks); | |
d070c424 | 170 | trace_kernel_free_session(lks); |
5f62c685 | 171 | } |
20fe2104 DG |
172 | return ret; |
173 | } | |
174 | ||
175 | /* | |
050349bb DG |
176 | * Create a kernel channel, register it to the kernel tracer and add it to the |
177 | * kernel session. | |
20fe2104 | 178 | */ |
050349bb | 179 | int kernel_create_channel(struct ltt_kernel_session *session, |
fdd9eb17 | 180 | struct lttng_channel *chan) |
20fe2104 DG |
181 | { |
182 | int ret; | |
183 | struct ltt_kernel_channel *lkc; | |
20fe2104 | 184 | |
0525e9ae DG |
185 | assert(session); |
186 | assert(chan); | |
0525e9ae | 187 | |
54012638 | 188 | /* Allocate kernel channel */ |
fdd9eb17 | 189 | lkc = trace_kernel_create_channel(chan); |
54012638 | 190 | if (lkc == NULL) { |
20fe2104 DG |
191 | goto error; |
192 | } | |
193 | ||
ecc48a90 | 194 | DBG3("Kernel create channel %s with attr: %d, %" PRIu64 ", %" PRIu64 ", %u, %u, %d, %d", |
fdd9eb17 | 195 | chan->name, lkc->channel->attr.overwrite, |
173af62f DG |
196 | lkc->channel->attr.subbuf_size, lkc->channel->attr.num_subbuf, |
197 | lkc->channel->attr.switch_timer_interval, lkc->channel->attr.read_timer_interval, | |
ecc48a90 | 198 | lkc->channel->attr.live_timer_interval, lkc->channel->attr.output); |
173af62f | 199 | |
54012638 | 200 | /* Kernel tracer channel creation */ |
f3ed775e | 201 | ret = kernctl_create_channel(session->fd, &lkc->channel->attr); |
20fe2104 | 202 | if (ret < 0) { |
df0f840b | 203 | PERROR("ioctl kernel create channel"); |
20fe2104 DG |
204 | goto error; |
205 | } | |
206 | ||
54012638 | 207 | /* Setup the channel fd */ |
20fe2104 | 208 | lkc->fd = ret; |
7b395890 DG |
209 | /* Prevent fd duplication after execlp() */ |
210 | ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC); | |
211 | if (ret < 0) { | |
df0f840b | 212 | PERROR("fcntl session fd"); |
7b395890 DG |
213 | } |
214 | ||
54012638 | 215 | /* Add channel to session */ |
8c0faa1d DG |
216 | cds_list_add(&lkc->list, &session->channel_list.head); |
217 | session->channel_count++; | |
fb5f35b6 | 218 | lkc->session = session; |
e1f3997a | 219 | lkc->key = ++next_kernel_channel_key; |
20fe2104 | 220 | |
e1f3997a JD |
221 | DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")", |
222 | lkc->channel->name, lkc->fd, lkc->key); | |
20fe2104 DG |
223 | |
224 | return 0; | |
225 | ||
226 | error: | |
5f62c685 DG |
227 | if (lkc) { |
228 | free(lkc->channel); | |
229 | free(lkc); | |
230 | } | |
54012638 | 231 | return -1; |
20fe2104 | 232 | } |
f34daff7 | 233 | |
352b58f5 JR |
234 | /* |
235 | * Create a kernel event notifier group, register it to the kernel tracer and | |
236 | * add it to the kernel session. | |
237 | */ | |
238 | static int kernel_create_event_notifier_group(int *event_notifier_group_fd) | |
239 | { | |
240 | int ret; | |
241 | int local_fd = -1; | |
242 | ||
243 | assert(event_notifier_group_fd); | |
244 | ||
245 | /* Kernel event notifier group creation. */ | |
246 | ret = kernctl_create_event_notifier_group(kernel_tracer_fd); | |
247 | if (ret < 0) { | |
248 | PERROR("Failed to create kernel event notifier group"); | |
249 | ret = -1; | |
250 | goto error; | |
251 | } | |
252 | ||
253 | local_fd = ret; | |
254 | ||
255 | /* Prevent fd duplication after execlp(). */ | |
256 | ret = fcntl(local_fd, F_SETFD, FD_CLOEXEC); | |
257 | if (ret < 0) { | |
258 | PERROR("Failed to set FD_CLOEXEC on kernel event notifier group file descriptor: fd = %d", | |
259 | local_fd); | |
260 | goto error; | |
261 | } | |
262 | ||
263 | DBG("Created kernel event notifier group: fd = %d", local_fd); | |
264 | *event_notifier_group_fd = local_fd; | |
265 | local_fd = -1; | |
266 | ret = 0; | |
267 | error: | |
268 | if (local_fd >= 0) { | |
269 | ret = close(local_fd); | |
270 | if (ret) { | |
271 | PERROR("Failed to close kernel event notifier group file descriptor: fd = %d", | |
272 | local_fd); | |
273 | } | |
274 | } | |
275 | ||
276 | return ret; | |
277 | } | |
278 | ||
410b78a0 FD |
279 | /* |
280 | * Compute the offset of the instrumentation byte in the binary based on the | |
281 | * function probe location using the ELF lookup method. | |
282 | * | |
283 | * Returns 0 on success and set the offset out parameter to the offset of the | |
284 | * elf symbol | |
285 | * Returns -1 on error | |
286 | */ | |
287 | static | |
288 | int extract_userspace_probe_offset_function_elf( | |
87597c2c | 289 | const struct lttng_userspace_probe_location *probe_location, |
0a398bc4 | 290 | uid_t uid, gid_t gid, uint64_t *offset) |
410b78a0 FD |
291 | { |
292 | int fd; | |
293 | int ret = 0; | |
294 | const char *symbol = NULL; | |
87597c2c | 295 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
296 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; |
297 | ||
410b78a0 FD |
298 | assert(lttng_userspace_probe_location_get_type(probe_location) == |
299 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_FUNCTION); | |
300 | ||
301 | lookup = lttng_userspace_probe_location_get_lookup_method( | |
302 | probe_location); | |
303 | if (!lookup) { | |
304 | ret = -1; | |
305 | goto end; | |
306 | } | |
307 | ||
308 | lookup_method_type = | |
309 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
310 | ||
311 | assert(lookup_method_type == | |
312 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF); | |
313 | ||
314 | symbol = lttng_userspace_probe_location_function_get_function_name( | |
315 | probe_location); | |
316 | if (!symbol) { | |
317 | ret = -1; | |
318 | goto end; | |
319 | } | |
320 | ||
321 | fd = lttng_userspace_probe_location_function_get_binary_fd(probe_location); | |
322 | if (fd < 0) { | |
323 | ret = -1; | |
324 | goto end; | |
325 | } | |
326 | ||
0a398bc4 | 327 | ret = run_as_extract_elf_symbol_offset(fd, symbol, uid, gid, offset); |
410b78a0 FD |
328 | if (ret < 0) { |
329 | DBG("userspace probe offset calculation failed for " | |
330 | "function %s", symbol); | |
331 | goto end; | |
332 | } | |
333 | ||
334 | DBG("userspace probe elf offset for %s is 0x%jd", symbol, (intmax_t)(*offset)); | |
335 | end: | |
336 | return ret; | |
337 | } | |
338 | ||
339 | /* | |
340 | * Compute the offsets of the instrumentation bytes in the binary based on the | |
341 | * tracepoint probe location using the SDT lookup method. This function | |
342 | * allocates the offsets buffer, the caller must free it. | |
343 | * | |
344 | * Returns 0 on success and set the offset out parameter to the offsets of the | |
345 | * SDT tracepoint. | |
346 | * Returns -1 on error. | |
347 | */ | |
348 | static | |
349 | int extract_userspace_probe_offset_tracepoint_sdt( | |
87597c2c | 350 | const struct lttng_userspace_probe_location *probe_location, |
0a398bc4 | 351 | uid_t uid, gid_t gid, uint64_t **offsets, |
410b78a0 FD |
352 | uint32_t *offsets_count) |
353 | { | |
354 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; | |
87597c2c | 355 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
356 | const char *probe_name = NULL, *provider_name = NULL; |
357 | int ret = 0; | |
358 | int fd, i; | |
359 | ||
360 | assert(lttng_userspace_probe_location_get_type(probe_location) == | |
361 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_TRACEPOINT); | |
362 | ||
363 | lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); | |
364 | if (!lookup) { | |
365 | ret = -1; | |
366 | goto end; | |
367 | } | |
368 | ||
369 | lookup_method_type = | |
370 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
371 | ||
372 | assert(lookup_method_type == | |
373 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT); | |
374 | ||
375 | ||
376 | probe_name = lttng_userspace_probe_location_tracepoint_get_probe_name( | |
377 | probe_location); | |
378 | if (!probe_name) { | |
379 | ret = -1; | |
380 | goto end; | |
381 | } | |
382 | ||
383 | provider_name = lttng_userspace_probe_location_tracepoint_get_provider_name( | |
384 | probe_location); | |
385 | if (!provider_name) { | |
386 | ret = -1; | |
387 | goto end; | |
388 | } | |
389 | ||
390 | fd = lttng_userspace_probe_location_tracepoint_get_binary_fd(probe_location); | |
391 | if (fd < 0) { | |
392 | ret = -1; | |
393 | goto end; | |
394 | } | |
395 | ||
396 | ret = run_as_extract_sdt_probe_offsets(fd, provider_name, probe_name, | |
0a398bc4 | 397 | uid, gid, offsets, offsets_count); |
410b78a0 FD |
398 | if (ret < 0) { |
399 | DBG("userspace probe offset calculation failed for sdt " | |
400 | "probe %s:%s", provider_name, probe_name); | |
401 | goto end; | |
402 | } | |
403 | ||
404 | if (*offsets_count == 0) { | |
405 | DBG("no userspace probe offset found"); | |
406 | goto end; | |
407 | } | |
408 | ||
409 | DBG("%u userspace probe SDT offsets found for %s:%s at:", | |
410 | *offsets_count, provider_name, probe_name); | |
411 | for (i = 0; i < *offsets_count; i++) { | |
412 | DBG("\t0x%jd", (intmax_t)((*offsets)[i])); | |
413 | } | |
414 | end: | |
415 | return ret; | |
416 | } | |
417 | ||
410b78a0 | 418 | static |
0a398bc4 FD |
419 | int userspace_probe_add_callsite( |
420 | const struct lttng_userspace_probe_location *location, | |
421 | uid_t uid, gid_t gid, int fd) | |
410b78a0 | 422 | { |
87597c2c | 423 | const struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL; |
410b78a0 | 424 | enum lttng_userspace_probe_location_lookup_method_type type; |
410b78a0 FD |
425 | int ret; |
426 | ||
0a398bc4 | 427 | lookup_method = lttng_userspace_probe_location_get_lookup_method(location); |
410b78a0 FD |
428 | if (!lookup_method) { |
429 | ret = -1; | |
430 | goto end; | |
431 | } | |
432 | ||
433 | type = lttng_userspace_probe_location_lookup_method_get_type(lookup_method); | |
434 | switch (type) { | |
435 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: | |
436 | { | |
437 | struct lttng_kernel_event_callsite callsite; | |
438 | uint64_t offset; | |
439 | ||
0a398bc4 FD |
440 | ret = extract_userspace_probe_offset_function_elf(location, |
441 | uid, gid, &offset); | |
410b78a0 FD |
442 | if (ret) { |
443 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
444 | goto end; | |
445 | } | |
446 | ||
447 | callsite.u.uprobe.offset = offset; | |
448 | ret = kernctl_add_callsite(fd, &callsite); | |
449 | if (ret) { | |
0a398bc4 | 450 | WARN("Failed to add callsite to ELF userspace probe."); |
410b78a0 FD |
451 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
452 | goto end; | |
453 | } | |
454 | break; | |
455 | } | |
456 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: | |
457 | { | |
458 | int i; | |
459 | uint64_t *offsets = NULL; | |
460 | uint32_t offsets_count; | |
461 | struct lttng_kernel_event_callsite callsite; | |
462 | ||
463 | /* | |
464 | * This call allocates the offsets buffer. This buffer must be freed | |
465 | * by the caller | |
466 | */ | |
0a398bc4 FD |
467 | ret = extract_userspace_probe_offset_tracepoint_sdt(location, |
468 | uid, gid, &offsets, &offsets_count); | |
410b78a0 FD |
469 | if (ret) { |
470 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
471 | goto end; | |
472 | } | |
473 | for (i = 0; i < offsets_count; i++) { | |
474 | callsite.u.uprobe.offset = offsets[i]; | |
475 | ret = kernctl_add_callsite(fd, &callsite); | |
476 | if (ret) { | |
0a398bc4 | 477 | WARN("Failed to add callsite to SDT userspace probe"); |
410b78a0 FD |
478 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
479 | free(offsets); | |
480 | goto end; | |
481 | } | |
482 | } | |
483 | free(offsets); | |
484 | break; | |
485 | } | |
486 | default: | |
487 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
488 | goto end; | |
489 | } | |
490 | end: | |
491 | return ret; | |
492 | } | |
493 | ||
0a398bc4 FD |
494 | /* |
495 | * Extract the offsets of the instrumentation point for the different lookup | |
496 | * methods. | |
497 | */ | |
498 | static | |
499 | int userspace_probe_event_add_callsites(struct lttng_event *ev, | |
500 | struct ltt_kernel_session *session, int fd) | |
501 | { | |
502 | int ret; | |
503 | const struct lttng_userspace_probe_location *location = NULL; | |
504 | ||
505 | assert(ev); | |
506 | assert(ev->type == LTTNG_EVENT_USERSPACE_PROBE); | |
507 | ||
508 | location = lttng_event_get_userspace_probe_location(ev); | |
509 | if (!location) { | |
510 | ret = -1; | |
511 | goto end; | |
512 | } | |
513 | ||
514 | ret = userspace_probe_add_callsite(location, session->uid, session->gid, | |
515 | fd); | |
516 | if (ret) { | |
517 | WARN("Failed to add callsite to userspace probe event '%s'", | |
518 | ev->name); | |
519 | } | |
520 | ||
521 | end: | |
522 | return ret; | |
523 | } | |
524 | ||
352b58f5 JR |
525 | /* |
526 | * Extract the offsets of the instrumentation point for the different look-up | |
527 | * methods. | |
528 | */ | |
529 | static int userspace_probe_event_rule_add_callsites( | |
530 | const struct lttng_event_rule *rule, | |
531 | const struct lttng_credentials *creds, | |
532 | int fd) | |
533 | { | |
534 | int ret; | |
535 | enum lttng_event_rule_status status; | |
536 | enum lttng_event_rule_type event_rule_type; | |
537 | const struct lttng_userspace_probe_location *location = NULL; | |
538 | ||
539 | assert(rule); | |
540 | assert(creds); | |
541 | ||
542 | event_rule_type = lttng_event_rule_get_type(rule); | |
543 | assert(event_rule_type == LTTNG_EVENT_RULE_TYPE_UPROBE); | |
544 | ||
545 | status = lttng_event_rule_uprobe_get_location(rule, &location); | |
546 | if (status != LTTNG_EVENT_RULE_STATUS_OK || !location) { | |
547 | ret = -1; | |
548 | goto end; | |
549 | } | |
550 | ||
551 | ret = userspace_probe_add_callsite(location, | |
552 | lttng_credentials_get_uid(creds), | |
553 | lttng_credentials_get_gid(creds), fd); | |
554 | if (ret) { | |
555 | WARN("Failed to add callsite to user space probe object: fd = %d", | |
556 | fd); | |
557 | } | |
558 | ||
559 | end: | |
560 | return ret; | |
561 | } | |
562 | ||
f34daff7 | 563 | /* |
050349bb DG |
564 | * Create a kernel event, enable it to the kernel tracer and add it to the |
565 | * channel event list of the kernel session. | |
49d21f93 | 566 | * We own filter_expression and filter. |
f34daff7 | 567 | */ |
050349bb | 568 | int kernel_create_event(struct lttng_event *ev, |
00a62084 MD |
569 | struct ltt_kernel_channel *channel, |
570 | char *filter_expression, | |
2b00d462 | 571 | struct lttng_bytecode *filter) |
f34daff7 | 572 | { |
71a3bb01 FD |
573 | int err, fd; |
574 | enum lttng_error_code ret; | |
f34daff7 | 575 | struct ltt_kernel_event *event; |
f34daff7 | 576 | |
0525e9ae DG |
577 | assert(ev); |
578 | assert(channel); | |
579 | ||
a969e101 | 580 | /* We pass ownership of filter_expression and filter */ |
71a3bb01 FD |
581 | ret = trace_kernel_create_event(ev, filter_expression, |
582 | filter, &event); | |
583 | if (ret != LTTNG_OK) { | |
f34daff7 DG |
584 | goto error; |
585 | } | |
586 | ||
71a3bb01 FD |
587 | fd = kernctl_create_event(channel->fd, event->event); |
588 | if (fd < 0) { | |
589 | switch (-fd) { | |
bd29c13d | 590 | case EEXIST: |
71a3bb01 | 591 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
bd29c13d DG |
592 | break; |
593 | case ENOSYS: | |
594 | WARN("Event type not implemented"); | |
71a3bb01 | 595 | ret = LTTNG_ERR_KERN_EVENT_ENOSYS; |
bd29c13d | 596 | break; |
8197a339 DG |
597 | case ENOENT: |
598 | WARN("Event %s not found!", ev->name); | |
71a3bb01 | 599 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
8197a339 | 600 | break; |
bd29c13d | 601 | default: |
71a3bb01 | 602 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
d87bfb32 DG |
603 | PERROR("create event ioctl"); |
604 | } | |
e953ef25 | 605 | goto free_event; |
8c0faa1d | 606 | } |
f34daff7 | 607 | |
d0ae4ea8 | 608 | event->type = ev->type; |
71a3bb01 | 609 | event->fd = fd; |
7b395890 | 610 | /* Prevent fd duplication after execlp() */ |
71a3bb01 FD |
611 | err = fcntl(event->fd, F_SETFD, FD_CLOEXEC); |
612 | if (err < 0) { | |
df0f840b | 613 | PERROR("fcntl session fd"); |
7b395890 DG |
614 | } |
615 | ||
00a62084 | 616 | if (filter) { |
71a3bb01 FD |
617 | err = kernctl_filter(event->fd, filter); |
618 | if (err < 0) { | |
619 | switch (-err) { | |
620 | case ENOMEM: | |
621 | ret = LTTNG_ERR_FILTER_NOMEM; | |
622 | break; | |
623 | default: | |
624 | ret = LTTNG_ERR_FILTER_INVAL; | |
625 | break; | |
626 | } | |
00a62084 MD |
627 | goto filter_error; |
628 | } | |
629 | } | |
630 | ||
dcabc190 | 631 | if (ev->type == LTTNG_EVENT_USERSPACE_PROBE) { |
0a398bc4 FD |
632 | ret = userspace_probe_event_add_callsites(ev, channel->session, |
633 | event->fd); | |
dcabc190 FD |
634 | if (ret) { |
635 | goto add_callsite_error; | |
636 | } | |
637 | } | |
638 | ||
71a3bb01 FD |
639 | err = kernctl_enable(event->fd); |
640 | if (err < 0) { | |
641 | switch (-err) { | |
00a62084 MD |
642 | case EEXIST: |
643 | ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
644 | break; | |
645 | default: | |
646 | PERROR("enable kernel event"); | |
71a3bb01 | 647 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
00a62084 MD |
648 | break; |
649 | } | |
650 | goto enable_error; | |
651 | } | |
652 | ||
f3ed775e DG |
653 | /* Add event to event list */ |
654 | cds_list_add(&event->list, &channel->events_list.head); | |
cbbbb275 DG |
655 | channel->event_count++; |
656 | ||
e953ef25 DG |
657 | DBG("Event %s created (fd: %d)", ev->name, event->fd); |
658 | ||
659 | return 0; | |
660 | ||
dcabc190 | 661 | add_callsite_error: |
00a62084 MD |
662 | enable_error: |
663 | filter_error: | |
664 | { | |
665 | int closeret; | |
666 | ||
667 | closeret = close(event->fd); | |
668 | if (closeret) { | |
669 | PERROR("close event fd"); | |
670 | } | |
671 | } | |
e953ef25 DG |
672 | free_event: |
673 | free(event); | |
674 | error: | |
d87bfb32 | 675 | return ret; |
e953ef25 DG |
676 | } |
677 | ||
26cc6b4e | 678 | /* |
050349bb | 679 | * Disable a kernel channel. |
26cc6b4e DG |
680 | */ |
681 | int kernel_disable_channel(struct ltt_kernel_channel *chan) | |
682 | { | |
683 | int ret; | |
684 | ||
0525e9ae DG |
685 | assert(chan); |
686 | ||
26cc6b4e DG |
687 | ret = kernctl_disable(chan->fd); |
688 | if (ret < 0) { | |
df0f840b | 689 | PERROR("disable chan ioctl"); |
26cc6b4e DG |
690 | goto error; |
691 | } | |
692 | ||
693 | chan->enabled = 0; | |
e1f3997a JD |
694 | DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")", |
695 | chan->channel->name, chan->fd, chan->key); | |
26cc6b4e DG |
696 | |
697 | return 0; | |
698 | ||
699 | error: | |
700 | return ret; | |
701 | } | |
702 | ||
d36b8583 | 703 | /* |
050349bb | 704 | * Enable a kernel channel. |
d36b8583 DG |
705 | */ |
706 | int kernel_enable_channel(struct ltt_kernel_channel *chan) | |
707 | { | |
708 | int ret; | |
709 | ||
0525e9ae DG |
710 | assert(chan); |
711 | ||
d36b8583 | 712 | ret = kernctl_enable(chan->fd); |
32af2c95 | 713 | if (ret < 0 && ret != -EEXIST) { |
df0f840b | 714 | PERROR("Enable kernel chan"); |
d36b8583 DG |
715 | goto error; |
716 | } | |
717 | ||
718 | chan->enabled = 1; | |
e1f3997a JD |
719 | DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")", |
720 | chan->channel->name, chan->fd, chan->key); | |
d36b8583 DG |
721 | |
722 | return 0; | |
723 | ||
724 | error: | |
725 | return ret; | |
726 | } | |
727 | ||
19e70852 | 728 | /* |
050349bb | 729 | * Enable a kernel event. |
19e70852 DG |
730 | */ |
731 | int kernel_enable_event(struct ltt_kernel_event *event) | |
732 | { | |
733 | int ret; | |
734 | ||
0525e9ae DG |
735 | assert(event); |
736 | ||
19e70852 | 737 | ret = kernctl_enable(event->fd); |
42224349 | 738 | if (ret < 0) { |
32af2c95 | 739 | switch (-ret) { |
42224349 | 740 | case EEXIST: |
f73fabfd | 741 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
742 | break; |
743 | default: | |
744 | PERROR("enable kernel event"); | |
745 | break; | |
746 | } | |
19e70852 DG |
747 | goto error; |
748 | } | |
749 | ||
750 | event->enabled = 1; | |
751 | DBG("Kernel event %s enabled (fd: %d)", event->event->name, event->fd); | |
752 | ||
753 | return 0; | |
754 | ||
755 | error: | |
d36b8583 | 756 | return ret; |
19e70852 DG |
757 | } |
758 | ||
e953ef25 | 759 | /* |
050349bb | 760 | * Disable a kernel event. |
e953ef25 | 761 | */ |
19e70852 | 762 | int kernel_disable_event(struct ltt_kernel_event *event) |
e953ef25 DG |
763 | { |
764 | int ret; | |
19e70852 | 765 | |
0525e9ae DG |
766 | assert(event); |
767 | ||
19e70852 | 768 | ret = kernctl_disable(event->fd); |
42224349 | 769 | if (ret < 0) { |
32af2c95 | 770 | switch (-ret) { |
42224349 | 771 | case EEXIST: |
f73fabfd | 772 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
773 | break; |
774 | default: | |
775 | PERROR("disable kernel event"); | |
776 | break; | |
777 | } | |
19e70852 | 778 | goto error; |
e953ef25 | 779 | } |
f3ed775e | 780 | |
19e70852 DG |
781 | event->enabled = 0; |
782 | DBG("Kernel event %s disabled (fd: %d)", event->event->name, event->fd); | |
783 | ||
f34daff7 DG |
784 | return 0; |
785 | ||
786 | error: | |
d36b8583 | 787 | return ret; |
f34daff7 | 788 | } |
aaf26714 | 789 | |
352b58f5 JR |
790 | /* |
791 | * Disable a kernel event notifier. | |
792 | */ | |
793 | static | |
794 | int kernel_disable_event_notifier_rule(struct ltt_kernel_event_notifier_rule *event) | |
795 | { | |
796 | int ret; | |
797 | ||
798 | assert(event); | |
799 | ||
800 | rcu_read_lock(); | |
801 | cds_lfht_del(kernel_token_to_event_notifier_rule_ht, &event->ht_node); | |
802 | rcu_read_unlock(); | |
803 | ||
804 | ret = kernctl_disable(event->fd); | |
805 | if (ret < 0) { | |
806 | switch (-ret) { | |
807 | case EEXIST: | |
808 | ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
809 | break; | |
810 | default: | |
811 | PERROR("Failed to disable kernel event notifier: fd = %d, token = %" PRIu64, | |
812 | event->fd, event->token); | |
813 | break; | |
814 | } | |
815 | goto error; | |
816 | } | |
817 | ||
818 | event->enabled = 0; | |
819 | DBG("Disabled kernel event notifier: fd = %d, token = %" PRIu64, | |
820 | event->fd, event->token); | |
821 | ||
822 | error: | |
823 | return ret; | |
824 | } | |
825 | ||
159b042f JG |
826 | static |
827 | struct process_attr_tracker *_kernel_get_process_attr_tracker( | |
55c9e7ca | 828 | struct ltt_kernel_session *session, |
159b042f | 829 | enum lttng_process_attr process_attr) |
55c9e7ca | 830 | { |
159b042f JG |
831 | switch (process_attr) { |
832 | case LTTNG_PROCESS_ATTR_PROCESS_ID: | |
833 | return session->tracker_pid; | |
834 | case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID: | |
835 | return session->tracker_vpid; | |
836 | case LTTNG_PROCESS_ATTR_USER_ID: | |
837 | return session->tracker_uid; | |
838 | case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID: | |
839 | return session->tracker_vuid; | |
840 | case LTTNG_PROCESS_ATTR_GROUP_ID: | |
841 | return session->tracker_gid; | |
842 | case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID: | |
843 | return session->tracker_vgid; | |
55c9e7ca JR |
844 | default: |
845 | return NULL; | |
846 | } | |
847 | } | |
6e911cad | 848 | |
159b042f | 849 | const struct process_attr_tracker *kernel_get_process_attr_tracker( |
55c9e7ca | 850 | struct ltt_kernel_session *session, |
159b042f | 851 | enum lttng_process_attr process_attr) |
ccf10263 | 852 | { |
159b042f JG |
853 | return (const struct process_attr_tracker *) |
854 | _kernel_get_process_attr_tracker(session, process_attr); | |
855 | } | |
7c493d31 | 856 | |
159b042f JG |
857 | enum lttng_error_code kernel_process_attr_tracker_set_tracking_policy( |
858 | struct ltt_kernel_session *session, | |
859 | enum lttng_process_attr process_attr, | |
860 | enum lttng_tracking_policy policy) | |
861 | { | |
862 | int ret; | |
863 | enum lttng_error_code ret_code = LTTNG_OK; | |
864 | struct process_attr_tracker *tracker = | |
865 | _kernel_get_process_attr_tracker(session, process_attr); | |
866 | enum lttng_tracking_policy previous_policy; | |
55c9e7ca | 867 | |
159b042f JG |
868 | if (!tracker) { |
869 | ret_code = LTTNG_ERR_INVALID; | |
870 | goto end; | |
7c493d31 | 871 | } |
ccf10263 | 872 | |
159b042f JG |
873 | previous_policy = process_attr_tracker_get_tracking_policy(tracker); |
874 | ret = process_attr_tracker_set_tracking_policy(tracker, policy); | |
875 | if (ret) { | |
876 | ret_code = LTTNG_ERR_UNK; | |
877 | goto end; | |
55c9e7ca | 878 | } |
7c493d31 | 879 | |
159b042f | 880 | if (previous_policy == policy) { |
55c9e7ca | 881 | goto end; |
7c493d31 | 882 | } |
55c9e7ca | 883 | |
159b042f JG |
884 | switch (policy) { |
885 | case LTTNG_TRACKING_POLICY_INCLUDE_ALL: | |
886 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
887 | /* | |
888 | * Maintain a special case for the process ID process | |
889 | * attribute tracker as it was the only supported | |
890 | * attribute prior to 2.12. | |
891 | */ | |
892 | ret = kernctl_track_pid(session->fd, -1); | |
893 | } else { | |
894 | ret = kernctl_track_id(session->fd, process_attr, -1); | |
55c9e7ca JR |
895 | } |
896 | break; | |
159b042f JG |
897 | case LTTNG_TRACKING_POLICY_EXCLUDE_ALL: |
898 | case LTTNG_TRACKING_POLICY_INCLUDE_SET: | |
899 | /* fall-through. */ | |
900 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
901 | /* | |
902 | * Maintain a special case for the process ID process | |
903 | * attribute tracker as it was the only supported | |
904 | * attribute prior to 2.12. | |
905 | */ | |
906 | ret = kernctl_untrack_pid(session->fd, -1); | |
907 | } else { | |
908 | ret = kernctl_untrack_id(session->fd, process_attr, -1); | |
55c9e7ca JR |
909 | } |
910 | break; | |
911 | default: | |
159b042f | 912 | abort(); |
55c9e7ca | 913 | } |
159b042f | 914 | /* kern-ctl error handling */ |
32af2c95 | 915 | switch (-ret) { |
159b042f JG |
916 | case 0: |
917 | ret_code = LTTNG_OK; | |
918 | break; | |
7c493d31 | 919 | case EINVAL: |
159b042f | 920 | ret_code = LTTNG_ERR_INVALID; |
55c9e7ca | 921 | break; |
7c493d31 | 922 | case ENOMEM: |
159b042f | 923 | ret_code = LTTNG_ERR_NOMEM; |
55c9e7ca JR |
924 | break; |
925 | case EEXIST: | |
159b042f | 926 | ret_code = LTTNG_ERR_PROCESS_ATTR_EXISTS; |
55c9e7ca | 927 | break; |
7c493d31 | 928 | default: |
159b042f | 929 | ret_code = LTTNG_ERR_UNK; |
55c9e7ca JR |
930 | break; |
931 | } | |
55c9e7ca | 932 | end: |
159b042f | 933 | return ret_code; |
ccf10263 MD |
934 | } |
935 | ||
159b042f | 936 | enum lttng_error_code kernel_process_attr_tracker_inclusion_set_add_value( |
55c9e7ca | 937 | struct ltt_kernel_session *session, |
159b042f JG |
938 | enum lttng_process_attr process_attr, |
939 | const struct process_attr_value *value) | |
a5dfbb9d | 940 | { |
159b042f JG |
941 | int ret, integral_value; |
942 | enum lttng_error_code ret_code; | |
943 | struct process_attr_tracker *tracker; | |
944 | enum process_attr_tracker_status status; | |
a5dfbb9d | 945 | |
159b042f JG |
946 | /* |
947 | * Convert process attribute tracker value to the integral | |
948 | * representation required by the kern-ctl API. | |
949 | */ | |
950 | switch (process_attr) { | |
951 | case LTTNG_PROCESS_ATTR_PROCESS_ID: | |
952 | case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID: | |
953 | integral_value = (int) value->value.pid; | |
55c9e7ca | 954 | break; |
159b042f JG |
955 | case LTTNG_PROCESS_ATTR_USER_ID: |
956 | case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID: | |
957 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME) { | |
958 | uid_t uid; | |
959 | ||
960 | ret_code = utils_user_id_from_name( | |
961 | value->value.user_name, &uid); | |
962 | if (ret_code != LTTNG_OK) { | |
963 | goto end; | |
964 | } | |
965 | integral_value = (int) uid; | |
966 | } else { | |
967 | integral_value = (int) value->value.uid; | |
55c9e7ca JR |
968 | } |
969 | break; | |
159b042f JG |
970 | case LTTNG_PROCESS_ATTR_GROUP_ID: |
971 | case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID: | |
972 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME) { | |
973 | gid_t gid; | |
974 | ||
975 | ret_code = utils_group_id_from_name( | |
976 | value->value.group_name, &gid); | |
977 | if (ret_code != LTTNG_OK) { | |
978 | goto end; | |
979 | } | |
980 | integral_value = (int) gid; | |
981 | } else { | |
982 | integral_value = (int) value->value.gid; | |
a5dfbb9d | 983 | } |
55c9e7ca JR |
984 | break; |
985 | default: | |
159b042f JG |
986 | ret_code = LTTNG_ERR_INVALID; |
987 | goto end; | |
55c9e7ca JR |
988 | } |
989 | ||
159b042f JG |
990 | tracker = _kernel_get_process_attr_tracker(session, process_attr); |
991 | if (!tracker) { | |
992 | ret_code = LTTNG_ERR_INVALID; | |
993 | goto end; | |
994 | } | |
995 | ||
996 | status = process_attr_tracker_inclusion_set_add_value(tracker, value); | |
997 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
998 | switch (status) { | |
999 | case PROCESS_ATTR_TRACKER_STATUS_EXISTS: | |
1000 | ret_code = LTTNG_ERR_PROCESS_ATTR_EXISTS; | |
1001 | break; | |
1002 | case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY: | |
1003 | ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY; | |
1004 | break; | |
1005 | case PROCESS_ATTR_TRACKER_STATUS_ERROR: | |
1006 | default: | |
1007 | ret_code = LTTNG_ERR_UNK; | |
1008 | break; | |
1009 | } | |
1010 | goto end; | |
1011 | } | |
1012 | ||
1013 | DBG("Kernel track %s %d for session id %" PRIu64, | |
1014 | lttng_process_attr_to_string(process_attr), | |
1015 | integral_value, session->id); | |
1016 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
1017 | /* | |
1018 | * Maintain a special case for the process ID process attribute | |
1019 | * tracker as it was the only supported attribute prior to 2.12. | |
1020 | */ | |
1021 | ret = kernctl_track_pid(session->fd, integral_value); | |
1022 | } else { | |
1023 | ret = kernctl_track_id( | |
1024 | session->fd, process_attr, integral_value); | |
1025 | } | |
1026 | if (ret == 0) { | |
1027 | ret_code = LTTNG_OK; | |
1028 | goto end; | |
1029 | } | |
1030 | ||
1031 | kernel_wait_quiescent(); | |
1032 | ||
1033 | /* kern-ctl error handling */ | |
55c9e7ca | 1034 | switch (-ret) { |
159b042f JG |
1035 | case 0: |
1036 | ret_code = LTTNG_OK; | |
1037 | break; | |
55c9e7ca | 1038 | case EINVAL: |
159b042f | 1039 | ret_code = LTTNG_ERR_INVALID; |
55c9e7ca JR |
1040 | break; |
1041 | case ENOMEM: | |
159b042f | 1042 | ret_code = LTTNG_ERR_NOMEM; |
55c9e7ca JR |
1043 | break; |
1044 | case EEXIST: | |
159b042f | 1045 | ret_code = LTTNG_ERR_PROCESS_ATTR_EXISTS; |
55c9e7ca JR |
1046 | break; |
1047 | default: | |
159b042f | 1048 | ret_code = LTTNG_ERR_UNK; |
55c9e7ca | 1049 | break; |
a5dfbb9d MD |
1050 | } |
1051 | ||
159b042f JG |
1052 | /* Attempt to remove the value from the tracker. */ |
1053 | status = process_attr_tracker_inclusion_set_remove_value( | |
1054 | tracker, value); | |
1055 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
1056 | ERR("Failed to roll-back the tracking of kernel %s process attribute %d while handling a kern-ctl error", | |
1057 | lttng_process_attr_to_string(process_attr), | |
1058 | integral_value); | |
55c9e7ca | 1059 | } |
a5dfbb9d | 1060 | end: |
159b042f | 1061 | return ret_code; |
55c9e7ca | 1062 | } |
a5dfbb9d | 1063 | |
159b042f | 1064 | enum lttng_error_code kernel_process_attr_tracker_inclusion_set_remove_value( |
55c9e7ca | 1065 | struct ltt_kernel_session *session, |
159b042f JG |
1066 | enum lttng_process_attr process_attr, |
1067 | const struct process_attr_value *value) | |
55c9e7ca | 1068 | { |
159b042f JG |
1069 | int ret, integral_value; |
1070 | enum lttng_error_code ret_code; | |
1071 | struct process_attr_tracker *tracker; | |
1072 | enum process_attr_tracker_status status; | |
1073 | ||
1074 | /* | |
1075 | * Convert process attribute tracker value to the integral | |
1076 | * representation required by the kern-ctl API. | |
1077 | */ | |
1078 | switch (process_attr) { | |
1079 | case LTTNG_PROCESS_ATTR_PROCESS_ID: | |
1080 | case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID: | |
1081 | integral_value = (int) value->value.pid; | |
1082 | break; | |
1083 | case LTTNG_PROCESS_ATTR_USER_ID: | |
1084 | case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID: | |
1085 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME) { | |
1086 | uid_t uid; | |
1087 | ||
1088 | ret_code = utils_user_id_from_name( | |
1089 | value->value.user_name, &uid); | |
1090 | if (ret_code != LTTNG_OK) { | |
1091 | goto end; | |
1092 | } | |
1093 | integral_value = (int) uid; | |
1094 | } else { | |
1095 | integral_value = (int) value->value.uid; | |
1096 | } | |
1097 | break; | |
1098 | case LTTNG_PROCESS_ATTR_GROUP_ID: | |
1099 | case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID: | |
1100 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME) { | |
1101 | gid_t gid; | |
1102 | ||
1103 | ret_code = utils_group_id_from_name( | |
1104 | value->value.group_name, &gid); | |
1105 | if (ret_code != LTTNG_OK) { | |
1106 | goto end; | |
1107 | } | |
1108 | integral_value = (int) gid; | |
1109 | } else { | |
1110 | integral_value = (int) value->value.gid; | |
1111 | } | |
1112 | break; | |
1113 | default: | |
1114 | ret_code = LTTNG_ERR_INVALID; | |
1115 | goto end; | |
1116 | } | |
55c9e7ca | 1117 | |
159b042f JG |
1118 | tracker = _kernel_get_process_attr_tracker(session, process_attr); |
1119 | if (!tracker) { | |
1120 | ret_code = LTTNG_ERR_INVALID; | |
a7a533cd | 1121 | goto end; |
a5dfbb9d | 1122 | } |
a7a533cd | 1123 | |
159b042f JG |
1124 | status = process_attr_tracker_inclusion_set_remove_value( |
1125 | tracker, value); | |
1126 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
1127 | switch (status) { | |
1128 | case PROCESS_ATTR_TRACKER_STATUS_MISSING: | |
1129 | ret_code = LTTNG_ERR_PROCESS_ATTR_MISSING; | |
1130 | break; | |
1131 | case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY: | |
1132 | ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY; | |
1133 | break; | |
1134 | case PROCESS_ATTR_TRACKER_STATUS_ERROR: | |
1135 | default: | |
1136 | ret_code = LTTNG_ERR_UNK; | |
1137 | break; | |
1138 | } | |
a7a533cd JR |
1139 | goto end; |
1140 | } | |
1141 | ||
159b042f JG |
1142 | DBG("Kernel track %s %d for session id %" PRIu64, |
1143 | lttng_process_attr_to_string(process_attr), | |
1144 | integral_value, session->id); | |
1145 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
1146 | /* | |
1147 | * Maintain a special case for the process ID process attribute | |
1148 | * tracker as it was the only supported attribute prior to 2.12. | |
1149 | */ | |
1150 | ret = kernctl_untrack_pid(session->fd, integral_value); | |
1151 | } else { | |
1152 | ret = kernctl_untrack_id( | |
1153 | session->fd, process_attr, integral_value); | |
1154 | } | |
1155 | if (ret == 0) { | |
1156 | ret_code = LTTNG_OK; | |
1157 | goto end; | |
1158 | } | |
1159 | kernel_wait_quiescent(); | |
1160 | ||
1161 | /* kern-ctl error handling */ | |
1162 | switch (-ret) { | |
1163 | case 0: | |
1164 | ret_code = LTTNG_OK; | |
1165 | break; | |
1166 | case EINVAL: | |
1167 | ret_code = LTTNG_ERR_INVALID; | |
1168 | break; | |
1169 | case ENOMEM: | |
1170 | ret_code = LTTNG_ERR_NOMEM; | |
1171 | break; | |
1172 | case ENOENT: | |
1173 | ret_code = LTTNG_ERR_PROCESS_ATTR_MISSING; | |
1174 | break; | |
1175 | default: | |
1176 | ret_code = LTTNG_ERR_UNK; | |
1177 | break; | |
1178 | } | |
1179 | ||
1180 | /* Attempt to add the value to the tracker. */ | |
1181 | status = process_attr_tracker_inclusion_set_add_value( | |
1182 | tracker, value); | |
1183 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
1184 | ERR("Failed to roll-back the tracking of kernel %s process attribute %d while handling a kern-ctl error", | |
1185 | lttng_process_attr_to_string(process_attr), | |
1186 | integral_value); | |
1187 | } | |
a7a533cd | 1188 | end: |
159b042f | 1189 | return ret_code; |
a5dfbb9d MD |
1190 | } |
1191 | ||
aaf26714 | 1192 | /* |
050349bb DG |
1193 | * Create kernel metadata, open from the kernel tracer and add it to the |
1194 | * kernel session. | |
aaf26714 | 1195 | */ |
a4b92340 | 1196 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
1197 | { |
1198 | int ret; | |
74024a21 | 1199 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 1200 | |
0525e9ae DG |
1201 | assert(session); |
1202 | ||
54012638 | 1203 | /* Allocate kernel metadata */ |
a4b92340 | 1204 | lkm = trace_kernel_create_metadata(); |
54012638 | 1205 | if (lkm == NULL) { |
aaf26714 DG |
1206 | goto error; |
1207 | } | |
1208 | ||
54012638 | 1209 | /* Kernel tracer metadata creation */ |
f3ed775e | 1210 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 1211 | if (ret < 0) { |
74024a21 | 1212 | goto error_open; |
aaf26714 DG |
1213 | } |
1214 | ||
8c0faa1d | 1215 | lkm->fd = ret; |
d40f0359 | 1216 | lkm->key = ++next_kernel_channel_key; |
7b395890 DG |
1217 | /* Prevent fd duplication after execlp() */ |
1218 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
1219 | if (ret < 0) { | |
df0f840b | 1220 | PERROR("fcntl session fd"); |
7b395890 DG |
1221 | } |
1222 | ||
aaf26714 | 1223 | session->metadata = lkm; |
8c0faa1d | 1224 | |
00e2e675 | 1225 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
1226 | |
1227 | return 0; | |
1228 | ||
74024a21 DG |
1229 | error_open: |
1230 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 1231 | error: |
54012638 | 1232 | return -1; |
8c0faa1d DG |
1233 | } |
1234 | ||
1235 | /* | |
050349bb | 1236 | * Start tracing session. |
8c0faa1d DG |
1237 | */ |
1238 | int kernel_start_session(struct ltt_kernel_session *session) | |
1239 | { | |
1240 | int ret; | |
1241 | ||
0525e9ae DG |
1242 | assert(session); |
1243 | ||
8c0faa1d DG |
1244 | ret = kernctl_start_session(session->fd); |
1245 | if (ret < 0) { | |
df0f840b | 1246 | PERROR("ioctl start session"); |
8c0faa1d DG |
1247 | goto error; |
1248 | } | |
1249 | ||
1250 | DBG("Kernel session started"); | |
1251 | ||
1252 | return 0; | |
1253 | ||
1254 | error: | |
1255 | return ret; | |
1256 | } | |
1257 | ||
f3ed775e | 1258 | /* |
050349bb | 1259 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e | 1260 | */ |
7d268848 | 1261 | void kernel_wait_quiescent(void) |
f3ed775e DG |
1262 | { |
1263 | int ret; | |
7d268848 | 1264 | int fd = kernel_tracer_fd; |
f3ed775e DG |
1265 | |
1266 | DBG("Kernel quiescent wait on %d", fd); | |
1267 | ||
1268 | ret = kernctl_wait_quiescent(fd); | |
1269 | if (ret < 0) { | |
df0f840b | 1270 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
1271 | ERR("Kernel quiescent wait failed"); |
1272 | } | |
1273 | } | |
1274 | ||
1275 | /* | |
f3ed775e DG |
1276 | * Force flush buffer of metadata. |
1277 | */ | |
1278 | int kernel_metadata_flush_buffer(int fd) | |
1279 | { | |
1280 | int ret; | |
1281 | ||
169d2cb7 DG |
1282 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
1283 | ||
f3ed775e DG |
1284 | ret = kernctl_buffer_flush(fd); |
1285 | if (ret < 0) { | |
00e2e675 | 1286 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
1287 | } |
1288 | ||
1289 | return 0; | |
1290 | } | |
1291 | ||
1292 | /* | |
050349bb | 1293 | * Force flush buffer for channel. |
f3ed775e DG |
1294 | */ |
1295 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
1296 | { | |
1297 | int ret; | |
1298 | struct ltt_kernel_stream *stream; | |
1299 | ||
0525e9ae DG |
1300 | assert(channel); |
1301 | ||
f3ed775e DG |
1302 | DBG("Flush buffer for channel %s", channel->channel->name); |
1303 | ||
1304 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
1305 | DBG("Flushing channel stream %d", stream->fd); | |
1306 | ret = kernctl_buffer_flush(stream->fd); | |
1307 | if (ret < 0) { | |
df0f840b | 1308 | PERROR("ioctl"); |
f3ed775e DG |
1309 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
1310 | stream->fd, ret); | |
1311 | } | |
1312 | } | |
1313 | ||
1314 | return 0; | |
1315 | } | |
1316 | ||
8c0faa1d | 1317 | /* |
050349bb | 1318 | * Stop tracing session. |
8c0faa1d DG |
1319 | */ |
1320 | int kernel_stop_session(struct ltt_kernel_session *session) | |
1321 | { | |
1322 | int ret; | |
1323 | ||
0525e9ae DG |
1324 | assert(session); |
1325 | ||
8c0faa1d DG |
1326 | ret = kernctl_stop_session(session->fd); |
1327 | if (ret < 0) { | |
1328 | goto error; | |
1329 | } | |
1330 | ||
1331 | DBG("Kernel session stopped"); | |
1332 | ||
1333 | return 0; | |
1334 | ||
1335 | error: | |
1336 | return ret; | |
1337 | } | |
1338 | ||
1339 | /* | |
050349bb DG |
1340 | * Open stream of channel, register it to the kernel tracer and add it |
1341 | * to the stream list of the channel. | |
8c0faa1d | 1342 | * |
1cfb4b98 MD |
1343 | * Note: given that the streams may appear in random order wrt CPU |
1344 | * number (e.g. cpu hotplug), the index value of the stream number in | |
1345 | * the stream name is not necessarily linked to the CPU number. | |
1346 | * | |
050349bb | 1347 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 1348 | */ |
f3ed775e | 1349 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 1350 | { |
1cfb4b98 | 1351 | int ret; |
8c0faa1d DG |
1352 | struct ltt_kernel_stream *lks; |
1353 | ||
0525e9ae DG |
1354 | assert(channel); |
1355 | ||
5a47c6a2 | 1356 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
1357 | lks = trace_kernel_create_stream(channel->channel->name, |
1358 | channel->stream_count); | |
8c0faa1d | 1359 | if (lks == NULL) { |
799e2c4f MD |
1360 | ret = close(ret); |
1361 | if (ret) { | |
1362 | PERROR("close"); | |
1363 | } | |
8c0faa1d DG |
1364 | goto error; |
1365 | } | |
1366 | ||
1367 | lks->fd = ret; | |
7b395890 DG |
1368 | /* Prevent fd duplication after execlp() */ |
1369 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
1370 | if (ret < 0) { | |
df0f840b | 1371 | PERROR("fcntl session fd"); |
7b395890 DG |
1372 | } |
1373 | ||
1624d5b7 JD |
1374 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
1375 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
1376 | ||
1cfb4b98 | 1377 | /* Add stream to channel stream list */ |
8c0faa1d DG |
1378 | cds_list_add(&lks->list, &channel->stream_list.head); |
1379 | channel->stream_count++; | |
8c0faa1d | 1380 | |
00e2e675 DG |
1381 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
1382 | lks->state); | |
54012638 | 1383 | } |
8c0faa1d DG |
1384 | |
1385 | return channel->stream_count; | |
1386 | ||
1387 | error: | |
54012638 | 1388 | return -1; |
8c0faa1d DG |
1389 | } |
1390 | ||
1391 | /* | |
050349bb | 1392 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 1393 | */ |
f3ed775e | 1394 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
1395 | { |
1396 | int ret; | |
1397 | ||
0525e9ae DG |
1398 | assert(session); |
1399 | ||
8c0faa1d DG |
1400 | ret = kernctl_create_stream(session->metadata->fd); |
1401 | if (ret < 0) { | |
df0f840b | 1402 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
1403 | goto error; |
1404 | } | |
1405 | ||
1406 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
1407 | session->metadata_stream_fd = ret; | |
7b395890 DG |
1408 | /* Prevent fd duplication after execlp() */ |
1409 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
1410 | if (ret < 0) { | |
df0f840b | 1411 | PERROR("fcntl session fd"); |
7b395890 | 1412 | } |
aaf26714 DG |
1413 | |
1414 | return 0; | |
1415 | ||
1416 | error: | |
54012638 | 1417 | return -1; |
aaf26714 | 1418 | } |
2ef84c95 DG |
1419 | |
1420 | /* | |
9f19cc17 | 1421 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 1422 | */ |
7d268848 | 1423 | ssize_t kernel_list_events(struct lttng_event **events) |
2ef84c95 | 1424 | { |
53efb85a | 1425 | int fd, ret; |
9f19cc17 DG |
1426 | char *event; |
1427 | size_t nbmem, count = 0; | |
2ef84c95 | 1428 | FILE *fp; |
9f19cc17 | 1429 | struct lttng_event *elist; |
2ef84c95 | 1430 | |
0525e9ae DG |
1431 | assert(events); |
1432 | ||
7d268848 | 1433 | fd = kernctl_tracepoint_list(kernel_tracer_fd); |
2ef84c95 | 1434 | if (fd < 0) { |
df0f840b | 1435 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
1436 | goto error; |
1437 | } | |
1438 | ||
1439 | fp = fdopen(fd, "r"); | |
1440 | if (fp == NULL) { | |
df0f840b | 1441 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 1442 | goto error_fp; |
2ef84c95 DG |
1443 | } |
1444 | ||
1445 | /* | |
1446 | * Init memory size counter | |
1447 | * See kernel-ctl.h for explanation of this value | |
1448 | */ | |
6725fe19 | 1449 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
ba7f0ae5 | 1450 | elist = zmalloc(sizeof(struct lttng_event) * nbmem); |
3b870559 MD |
1451 | if (elist == NULL) { |
1452 | PERROR("alloc list events"); | |
1453 | count = -ENOMEM; | |
1454 | goto end; | |
1455 | } | |
2ef84c95 | 1456 | |
53efb85a | 1457 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 1458 | if (count >= nbmem) { |
3b870559 | 1459 | struct lttng_event *new_elist; |
53efb85a | 1460 | size_t new_nbmem; |
3b870559 | 1461 | |
53efb85a MD |
1462 | new_nbmem = nbmem << 1; |
1463 | DBG("Reallocating event list from %zu to %zu bytes", | |
1464 | nbmem, new_nbmem); | |
1465 | new_elist = realloc(elist, new_nbmem * sizeof(struct lttng_event)); | |
3b870559 | 1466 | if (new_elist == NULL) { |
df0f840b | 1467 | PERROR("realloc list events"); |
3b870559 MD |
1468 | free(event); |
1469 | free(elist); | |
61b73b12 MD |
1470 | count = -ENOMEM; |
1471 | goto end; | |
2ef84c95 | 1472 | } |
53efb85a MD |
1473 | /* Zero the new memory */ |
1474 | memset(new_elist + nbmem, 0, | |
1475 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
1476 | nbmem = new_nbmem; | |
3b870559 | 1477 | elist = new_elist; |
2ef84c95 | 1478 | } |
99497cd0 MD |
1479 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
1480 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 1481 | elist[count].enabled = -1; |
9f19cc17 | 1482 | count++; |
3b870559 | 1483 | free(event); |
2ef84c95 DG |
1484 | } |
1485 | ||
9f19cc17 | 1486 | *events = elist; |
ced2f820 | 1487 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 1488 | end: |
799e2c4f MD |
1489 | ret = fclose(fp); /* closes both fp and fd */ |
1490 | if (ret) { | |
1491 | PERROR("fclose"); | |
1492 | } | |
9f19cc17 | 1493 | return count; |
2ef84c95 | 1494 | |
61b73b12 | 1495 | error_fp: |
799e2c4f MD |
1496 | ret = close(fd); |
1497 | if (ret) { | |
1498 | PERROR("close"); | |
1499 | } | |
2ef84c95 DG |
1500 | error: |
1501 | return -1; | |
1502 | } | |
096102bd DG |
1503 | |
1504 | /* | |
1505 | * Get kernel version and validate it. | |
1506 | */ | |
7d268848 | 1507 | int kernel_validate_version(struct lttng_kernel_tracer_version *version, |
88076e89 | 1508 | struct lttng_kernel_tracer_abi_version *abi_version) |
096102bd DG |
1509 | { |
1510 | int ret; | |
096102bd | 1511 | |
7d268848 | 1512 | ret = kernctl_tracer_version(kernel_tracer_fd, version); |
096102bd | 1513 | if (ret < 0) { |
521dd134 | 1514 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
1515 | goto error; |
1516 | } | |
1517 | ||
1518 | /* Validate version */ | |
88076e89 | 1519 | if (version->major != VERSION_MAJOR) { |
c052142c | 1520 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", |
88076e89 | 1521 | version->major, VERSION_MAJOR); |
096102bd | 1522 | goto error_version; |
096102bd | 1523 | } |
7d268848 | 1524 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, abi_version); |
c052142c | 1525 | if (ret < 0) { |
521dd134 | 1526 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
1527 | goto error; |
1528 | } | |
88076e89 | 1529 | if (abi_version->major != LTTNG_MODULES_ABI_MAJOR_VERSION) { |
521dd134 | 1530 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
88076e89 | 1531 | abi_version->major, abi_version->minor, |
c052142c MD |
1532 | LTTNG_MODULES_ABI_MAJOR_VERSION); |
1533 | goto error; | |
1534 | } | |
1535 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
88076e89 JD |
1536 | version->major, version->minor, |
1537 | abi_version->major, abi_version->minor); | |
096102bd DG |
1538 | return 0; |
1539 | ||
1540 | error_version: | |
096102bd DG |
1541 | ret = -1; |
1542 | ||
1543 | error: | |
521dd134 | 1544 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
1545 | return ret; |
1546 | } | |
335a95b7 MD |
1547 | |
1548 | /* | |
1549 | * Kernel work-arounds called at the start of sessiond main(). | |
1550 | */ | |
1551 | int init_kernel_workarounds(void) | |
1552 | { | |
8936c33a | 1553 | int ret; |
335a95b7 MD |
1554 | FILE *fp; |
1555 | ||
1556 | /* | |
1557 | * boot_id needs to be read once before being used concurrently | |
1558 | * to deal with a Linux kernel race. A fix is proposed for | |
1559 | * upstream, but the work-around is needed for older kernels. | |
1560 | */ | |
1561 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
1562 | if (!fp) { | |
1563 | goto end_boot_id; | |
1564 | } | |
1565 | while (!feof(fp)) { | |
1566 | char buf[37] = ""; | |
1567 | ||
8936c33a DG |
1568 | ret = fread(buf, 1, sizeof(buf), fp); |
1569 | if (ret < 0) { | |
1570 | /* Ignore error, we don't really care */ | |
1571 | } | |
335a95b7 | 1572 | } |
799e2c4f MD |
1573 | ret = fclose(fp); |
1574 | if (ret) { | |
1575 | PERROR("fclose"); | |
1576 | } | |
335a95b7 | 1577 | end_boot_id: |
335a95b7 MD |
1578 | return 0; |
1579 | } | |
2f77fc4b DG |
1580 | |
1581 | /* | |
d070c424 | 1582 | * Teardown of a kernel session, keeping data required by destroy notifiers. |
2f77fc4b DG |
1583 | */ |
1584 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
1585 | { | |
82b69413 JG |
1586 | struct lttng_trace_chunk *trace_chunk; |
1587 | ||
2f77fc4b DG |
1588 | if (ksess == NULL) { |
1589 | DBG3("No kernel session when tearing down session"); | |
1590 | return; | |
1591 | } | |
1592 | ||
1593 | DBG("Tearing down kernel session"); | |
82b69413 | 1594 | trace_chunk = ksess->current_trace_chunk; |
2f77fc4b | 1595 | |
07b86b52 | 1596 | /* |
15dc512a DG |
1597 | * Destroy channels on the consumer if at least one FD has been sent and we |
1598 | * are in no output mode because the streams are in *no* monitor mode so we | |
1599 | * have to send a command to clean them up or else they leaked. | |
07b86b52 | 1600 | */ |
15dc512a | 1601 | if (!ksess->output_traces && ksess->consumer_fds_sent) { |
07b86b52 JD |
1602 | int ret; |
1603 | struct consumer_socket *socket; | |
1604 | struct lttng_ht_iter iter; | |
1605 | ||
1606 | /* For each consumer socket. */ | |
d069d577 | 1607 | rcu_read_lock(); |
07b86b52 JD |
1608 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, |
1609 | socket, node.node) { | |
1610 | struct ltt_kernel_channel *chan; | |
1611 | ||
1612 | /* For each channel, ask the consumer to destroy it. */ | |
1613 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1614 | ret = kernel_consumer_destroy_channel(socket, chan); | |
1615 | if (ret < 0) { | |
1616 | /* Consumer is probably dead. Use next socket. */ | |
1617 | continue; | |
1618 | } | |
1619 | } | |
1620 | } | |
d069d577 | 1621 | rcu_read_unlock(); |
07b86b52 JD |
1622 | } |
1623 | ||
2f77fc4b DG |
1624 | /* Close any relayd session */ |
1625 | consumer_output_send_destroy_relayd(ksess->consumer); | |
1626 | ||
1627 | trace_kernel_destroy_session(ksess); | |
82b69413 | 1628 | lttng_trace_chunk_put(trace_chunk); |
2f77fc4b | 1629 | } |
fb5f35b6 | 1630 | |
d070c424 MD |
1631 | /* Teardown of data required by destroy notifiers. */ |
1632 | void kernel_free_session(struct ltt_kernel_session *ksess) | |
1633 | { | |
1634 | if (ksess == NULL) { | |
1635 | return; | |
1636 | } | |
1637 | trace_kernel_free_session(ksess); | |
1638 | } | |
1639 | ||
fb5f35b6 DG |
1640 | /* |
1641 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
1642 | */ | |
1643 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
1644 | { | |
1645 | struct ltt_kernel_session *ksess = NULL; | |
1646 | ||
1647 | assert(kchan); | |
1648 | assert(kchan->channel); | |
1649 | ||
1650 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
1651 | ||
1652 | /* Update channel count of associated session. */ | |
1653 | if (kchan->session) { | |
1654 | /* Keep pointer reference so we can update it after the destroy. */ | |
1655 | ksess = kchan->session; | |
1656 | } | |
1657 | ||
1658 | trace_kernel_destroy_channel(kchan); | |
1659 | ||
1660 | /* | |
1661 | * At this point the kernel channel is not visible anymore. This is safe | |
1662 | * since in order to work on a visible kernel session, the tracing session | |
1663 | * lock (ltt_session.lock) MUST be acquired. | |
1664 | */ | |
1665 | if (ksess) { | |
1666 | ksess->channel_count--; | |
1667 | } | |
1668 | } | |
6dc3064a DG |
1669 | |
1670 | /* | |
1671 | * Take a snapshot for a given kernel session. | |
1672 | * | |
9a654598 | 1673 | * Return LTTNG_OK on success or else return a LTTNG_ERR code. |
6dc3064a | 1674 | */ |
fb9a95c4 JG |
1675 | enum lttng_error_code kernel_snapshot_record( |
1676 | struct ltt_kernel_session *ksess, | |
348a81dc | 1677 | const struct consumer_output *output, int wait, |
d07ceecd | 1678 | uint64_t nb_packets_per_stream) |
6dc3064a | 1679 | { |
2a06df8d | 1680 | int err, ret, saved_metadata_fd; |
9a654598 | 1681 | enum lttng_error_code status = LTTNG_OK; |
6dc3064a DG |
1682 | struct consumer_socket *socket; |
1683 | struct lttng_ht_iter iter; | |
1684 | struct ltt_kernel_metadata *saved_metadata; | |
3b967712 | 1685 | char *trace_path = NULL; |
5da88b0f | 1686 | size_t consumer_path_offset = 0; |
6dc3064a DG |
1687 | |
1688 | assert(ksess); | |
1689 | assert(ksess->consumer); | |
1690 | assert(output); | |
1691 | ||
1692 | DBG("Kernel snapshot record started"); | |
1693 | ||
1694 | /* Save current metadata since the following calls will change it. */ | |
1695 | saved_metadata = ksess->metadata; | |
1696 | saved_metadata_fd = ksess->metadata_stream_fd; | |
1697 | ||
1698 | rcu_read_lock(); | |
1699 | ||
1700 | ret = kernel_open_metadata(ksess); | |
1701 | if (ret < 0) { | |
9a654598 | 1702 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1703 | goto error; |
1704 | } | |
1705 | ||
1706 | ret = kernel_open_metadata_stream(ksess); | |
1707 | if (ret < 0) { | |
9a654598 | 1708 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1709 | goto error_open_stream; |
1710 | } | |
1711 | ||
3b967712 | 1712 | trace_path = setup_channel_trace_path(ksess->consumer, |
5da88b0f | 1713 | DEFAULT_KERNEL_TRACE_DIR, &consumer_path_offset); |
3b967712 MD |
1714 | if (!trace_path) { |
1715 | status = LTTNG_ERR_INVALID; | |
1716 | goto error; | |
1717 | } | |
6dc3064a | 1718 | /* Send metadata to consumer and snapshot everything. */ |
348a81dc | 1719 | cds_lfht_for_each_entry(output->socks->ht, &iter.iter, |
6dc3064a | 1720 | socket, node.node) { |
6dc3064a | 1721 | struct ltt_kernel_channel *chan; |
6dc3064a | 1722 | |
6dc3064a DG |
1723 | pthread_mutex_lock(socket->lock); |
1724 | /* This stream must not be monitored by the consumer. */ | |
07b86b52 | 1725 | ret = kernel_consumer_add_metadata(socket, ksess, 0); |
6dc3064a | 1726 | pthread_mutex_unlock(socket->lock); |
6dc3064a | 1727 | if (ret < 0) { |
0ed78e50 | 1728 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1729 | goto error_consumer; |
1730 | } | |
1731 | ||
1732 | /* For each channel, ask the consumer to snapshot it. */ | |
1733 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
9a654598 | 1734 | status = consumer_snapshot_channel(socket, chan->key, output, 0, |
5c786ded | 1735 | ksess->uid, ksess->gid, |
5da88b0f | 1736 | &trace_path[consumer_path_offset], wait, |
d2956687 | 1737 | nb_packets_per_stream); |
9a654598 | 1738 | if (status != LTTNG_OK) { |
2a06df8d DG |
1739 | (void) kernel_consumer_destroy_metadata(socket, |
1740 | ksess->metadata); | |
6dc3064a DG |
1741 | goto error_consumer; |
1742 | } | |
1743 | } | |
1744 | ||
1745 | /* Snapshot metadata, */ | |
9a654598 | 1746 | status = consumer_snapshot_channel(socket, ksess->metadata->key, output, |
5da88b0f MD |
1747 | 1, ksess->uid, ksess->gid, &trace_path[consumer_path_offset], |
1748 | wait, 0); | |
9a654598 | 1749 | if (status != LTTNG_OK) { |
6dc3064a DG |
1750 | goto error_consumer; |
1751 | } | |
07b86b52 JD |
1752 | |
1753 | /* | |
1754 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1755 | * it's not monitored on the consumer side. | |
1756 | */ | |
1757 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1758 | } |
1759 | ||
1760 | error_consumer: | |
1761 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1762 | err = close(ksess->metadata_stream_fd); |
1763 | if (err < 0) { | |
6dc3064a DG |
1764 | PERROR("close snapshot kernel"); |
1765 | } | |
1766 | ||
1767 | error_open_stream: | |
1768 | trace_kernel_destroy_metadata(ksess->metadata); | |
1769 | error: | |
1770 | /* Restore metadata state.*/ | |
1771 | ksess->metadata = saved_metadata; | |
1772 | ksess->metadata_stream_fd = saved_metadata_fd; | |
6dc3064a | 1773 | rcu_read_unlock(); |
3b967712 | 1774 | free(trace_path); |
9a654598 | 1775 | return status; |
6dc3064a | 1776 | } |
834978fd DG |
1777 | |
1778 | /* | |
1779 | * Get the syscall mask array from the kernel tracer. | |
1780 | * | |
1781 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1782 | * be freed. | |
1783 | */ | |
1784 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1785 | { | |
1786 | assert(syscall_mask); | |
1787 | assert(nr_bits); | |
1788 | ||
1789 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1790 | } | |
6e21424e | 1791 | |
959e3c66 JR |
1792 | static |
1793 | int kernel_tracer_abi_greater_or_equal(unsigned int major, unsigned int minor) | |
6e21424e | 1794 | { |
959e3c66 | 1795 | int ret; |
6e21424e JR |
1796 | struct lttng_kernel_tracer_abi_version abi; |
1797 | ||
7d268848 | 1798 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, &abi); |
6e21424e JR |
1799 | if (ret < 0) { |
1800 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1801 | goto error; | |
1802 | } | |
1803 | ||
959e3c66 JR |
1804 | ret = abi.major > major || (abi.major == major && abi.minor >= minor); |
1805 | error: | |
1806 | return ret; | |
1807 | } | |
1808 | ||
1809 | /* | |
1810 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1811 | * version number. | |
1812 | * | |
1813 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1814 | * of errors. | |
1815 | */ | |
1816 | int kernel_supports_ring_buffer_snapshot_sample_positions(void) | |
1817 | { | |
6e21424e JR |
1818 | /* |
1819 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1820 | */ | |
959e3c66 | 1821 | return kernel_tracer_abi_greater_or_equal(2, 3); |
6e21424e | 1822 | } |
5c408ad8 | 1823 | |
a40a503f MD |
1824 | /* |
1825 | * Check for the support of the packet sequence number via abi version number. | |
1826 | * | |
1827 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1828 | * of errors. | |
1829 | */ | |
1830 | int kernel_supports_ring_buffer_packet_sequence_number(void) | |
1831 | { | |
a40a503f | 1832 | /* |
3029bc92 JG |
1833 | * Packet sequence number was introduced in LTTng 2.8, |
1834 | * lttng-modules ABI 2.1. | |
a40a503f | 1835 | */ |
959e3c66 JR |
1836 | return kernel_tracer_abi_greater_or_equal(2, 1); |
1837 | } | |
1838 | ||
1839 | /* | |
1840 | * Check for the support of event notifiers via abi version number. | |
1841 | * | |
1842 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1843 | * of errors. | |
1844 | */ | |
1845 | int kernel_supports_event_notifiers(void) | |
1846 | { | |
1847 | /* | |
1848 | * Event notifiers were introduced in LTTng 2.13, lttng-modules ABI 2.6. | |
1849 | */ | |
1850 | return kernel_tracer_abi_greater_or_equal(2, 6); | |
a40a503f MD |
1851 | } |
1852 | ||
5c408ad8 JD |
1853 | /* |
1854 | * Rotate a kernel session. | |
1855 | * | |
d5a1b7aa | 1856 | * Return LTTNG_OK on success or else an LTTng error code. |
5c408ad8 | 1857 | */ |
d5a1b7aa | 1858 | enum lttng_error_code kernel_rotate_session(struct ltt_session *session) |
5c408ad8 JD |
1859 | { |
1860 | int ret; | |
d5a1b7aa | 1861 | enum lttng_error_code status = LTTNG_OK; |
5c408ad8 JD |
1862 | struct consumer_socket *socket; |
1863 | struct lttng_ht_iter iter; | |
1864 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1865 | ||
1866 | assert(ksess); | |
1867 | assert(ksess->consumer); | |
1868 | ||
1869 | DBG("Rotate kernel session %s started (session %" PRIu64 ")", | |
1870 | session->name, session->id); | |
1871 | ||
1872 | rcu_read_lock(); | |
1873 | ||
1874 | /* | |
1875 | * Note that this loop will end after one iteration given that there is | |
1876 | * only one kernel consumer. | |
1877 | */ | |
1878 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1879 | socket, node.node) { | |
1880 | struct ltt_kernel_channel *chan; | |
1881 | ||
b8a1b0bd | 1882 | /* For each channel, ask the consumer to rotate it. */ |
5c408ad8 | 1883 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { |
92816cc3 JG |
1884 | DBG("Rotate kernel channel %" PRIu64 ", session %s", |
1885 | chan->key, session->name); | |
5c408ad8 JD |
1886 | ret = consumer_rotate_channel(socket, chan->key, |
1887 | ksess->uid, ksess->gid, ksess->consumer, | |
d2956687 | 1888 | /* is_metadata_channel */ false); |
5c408ad8 | 1889 | if (ret < 0) { |
7e0de219 | 1890 | status = LTTNG_ERR_ROTATION_FAIL_CONSUMER; |
5c408ad8 JD |
1891 | goto error; |
1892 | } | |
1893 | } | |
1894 | ||
1895 | /* | |
1896 | * Rotate the metadata channel. | |
1897 | */ | |
22a1b931 | 1898 | ret = consumer_rotate_channel(socket, ksess->metadata->key, |
5c408ad8 | 1899 | ksess->uid, ksess->gid, ksess->consumer, |
d2956687 | 1900 | /* is_metadata_channel */ true); |
5c408ad8 | 1901 | if (ret < 0) { |
7e0de219 | 1902 | status = LTTNG_ERR_ROTATION_FAIL_CONSUMER; |
5c408ad8 JD |
1903 | goto error; |
1904 | } | |
1905 | } | |
1906 | ||
5c408ad8 JD |
1907 | error: |
1908 | rcu_read_unlock(); | |
d5a1b7aa | 1909 | return status; |
5c408ad8 | 1910 | } |
d2956687 JG |
1911 | |
1912 | enum lttng_error_code kernel_create_channel_subdirectories( | |
1913 | const struct ltt_kernel_session *ksess) | |
1914 | { | |
1915 | enum lttng_error_code ret = LTTNG_OK; | |
1916 | enum lttng_trace_chunk_status chunk_status; | |
1917 | ||
1918 | rcu_read_lock(); | |
1919 | assert(ksess->current_trace_chunk); | |
1920 | ||
1921 | /* | |
1922 | * Create the index subdirectory which will take care | |
1923 | * of implicitly creating the channel's path. | |
1924 | */ | |
1925 | chunk_status = lttng_trace_chunk_create_subdirectory( | |
1926 | ksess->current_trace_chunk, | |
1927 | DEFAULT_KERNEL_TRACE_DIR "/" DEFAULT_INDEX_DIR); | |
1928 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { | |
1929 | ret = LTTNG_ERR_CREATE_DIR_FAIL; | |
1930 | goto error; | |
1931 | } | |
1932 | error: | |
1933 | rcu_read_unlock(); | |
1934 | return ret; | |
1935 | } | |
7d268848 MD |
1936 | |
1937 | /* | |
1938 | * Setup necessary data for kernel tracer action. | |
1939 | */ | |
1940 | LTTNG_HIDDEN | |
1941 | int init_kernel_tracer(void) | |
1942 | { | |
1943 | int ret; | |
1944 | bool is_root = !getuid(); | |
1945 | ||
1946 | /* Modprobe lttng kernel modules */ | |
1947 | ret = modprobe_lttng_control(); | |
1948 | if (ret < 0) { | |
1949 | goto error; | |
1950 | } | |
1951 | ||
1952 | /* Open debugfs lttng */ | |
1953 | kernel_tracer_fd = open(module_proc_lttng, O_RDWR); | |
1954 | if (kernel_tracer_fd < 0) { | |
1955 | DBG("Failed to open %s", module_proc_lttng); | |
1956 | goto error_open; | |
1957 | } | |
1958 | ||
1959 | /* Validate kernel version */ | |
1960 | ret = kernel_validate_version(&kernel_tracer_version, | |
1961 | &kernel_tracer_abi_version); | |
1962 | if (ret < 0) { | |
1963 | goto error_version; | |
1964 | } | |
1965 | ||
1966 | ret = modprobe_lttng_data(); | |
1967 | if (ret < 0) { | |
1968 | goto error_modules; | |
1969 | } | |
1970 | ||
1971 | ret = kernel_supports_ring_buffer_snapshot_sample_positions(); | |
1972 | if (ret < 0) { | |
1973 | goto error_modules; | |
1974 | } | |
7d268848 MD |
1975 | if (ret < 1) { |
1976 | WARN("Kernel tracer does not support buffer monitoring. " | |
1977 | "The monitoring timer of channels in the kernel domain " | |
1978 | "will be set to 0 (disabled)."); | |
1979 | } | |
1980 | ||
352b58f5 JR |
1981 | ret = kernel_supports_event_notifiers(); |
1982 | if (ret < 0) { | |
1983 | ERR("Failed to check for kernel tracer event notifier support"); | |
1984 | goto error_modules; | |
1985 | } | |
1986 | ret = kernel_create_event_notifier_group(&kernel_tracer_event_notifier_group_fd); | |
1987 | if (ret < 0) { | |
1988 | /* This is not fatal. */ | |
1989 | WARN("Failed to create kernel event notifier group"); | |
1990 | kernel_tracer_event_notifier_group_fd = -1; | |
1991 | } else { | |
1992 | const enum lttng_error_code error_code_ret = | |
1993 | kernel_create_event_notifier_group_notification_fd( | |
1994 | &kernel_tracer_event_notifier_group_notification_fd); | |
1995 | ||
1996 | if (error_code_ret != LTTNG_OK) { | |
1997 | goto error_modules; | |
1998 | } | |
1999 | ||
2000 | kernel_token_to_event_notifier_rule_ht = cds_lfht_new( | |
2001 | DEFAULT_HT_SIZE, 1, 0, | |
2002 | CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, | |
2003 | NULL); | |
2004 | if (!kernel_token_to_event_notifier_rule_ht) { | |
2005 | goto error_token_ht; | |
2006 | } | |
2007 | } | |
2008 | ||
2009 | DBG("Kernel tracer initialized: kernel tracer fd = %d, event notifier group fd = %d, event notifier group notification fd = %d", | |
2010 | kernel_tracer_fd, kernel_tracer_event_notifier_group_fd, | |
2011 | kernel_tracer_event_notifier_group_notification_fd); | |
7d268848 MD |
2012 | |
2013 | ret = syscall_init_table(kernel_tracer_fd); | |
2014 | if (ret < 0) { | |
2015 | ERR("Unable to populate syscall table. Syscall tracing won't " | |
2016 | "work for this session daemon."); | |
2017 | } | |
352b58f5 | 2018 | |
7d268848 MD |
2019 | return 0; |
2020 | ||
2021 | error_version: | |
2022 | modprobe_remove_lttng_control(); | |
2023 | ret = close(kernel_tracer_fd); | |
2024 | if (ret) { | |
352b58f5 JR |
2025 | PERROR("Failed to close kernel tracer file descriptor: fd = %d", |
2026 | kernel_tracer_fd); | |
7d268848 MD |
2027 | } |
2028 | kernel_tracer_fd = -1; | |
2029 | return LTTNG_ERR_KERN_VERSION; | |
2030 | ||
352b58f5 JR |
2031 | |
2032 | error_token_ht: | |
2033 | ret = close(kernel_tracer_event_notifier_group_notification_fd); | |
2034 | if (ret) { | |
2035 | PERROR("Failed to close kernel tracer event notifier group notification file descriptor: fd = %d", | |
2036 | kernel_tracer_event_notifier_group_notification_fd); | |
2037 | } | |
2038 | ||
7d268848 | 2039 | error_modules: |
352b58f5 JR |
2040 | ret = close(kernel_tracer_event_notifier_group_fd); |
2041 | if (ret) { | |
2042 | PERROR("Failed to close kernel tracer event notifier group file descriptor: fd = %d", | |
2043 | kernel_tracer_event_notifier_group_fd); | |
2044 | } | |
2045 | ||
7d268848 MD |
2046 | ret = close(kernel_tracer_fd); |
2047 | if (ret) { | |
352b58f5 JR |
2048 | PERROR("Failed to close kernel tracer file descriptor: fd = %d", |
2049 | kernel_tracer_fd); | |
7d268848 MD |
2050 | } |
2051 | ||
2052 | error_open: | |
2053 | modprobe_remove_lttng_control(); | |
2054 | ||
2055 | error: | |
2056 | WARN("No kernel tracer available"); | |
2057 | kernel_tracer_fd = -1; | |
2058 | if (!is_root) { | |
2059 | return LTTNG_ERR_NEED_ROOT_SESSIOND; | |
2060 | } else { | |
2061 | return LTTNG_ERR_KERN_NA; | |
2062 | } | |
2063 | } | |
2064 | ||
2065 | LTTNG_HIDDEN | |
2066 | void cleanup_kernel_tracer(void) | |
2067 | { | |
352b58f5 JR |
2068 | DBG2("Closing kernel event notifier group notification file descriptor"); |
2069 | if (kernel_tracer_event_notifier_group_notification_fd >= 0) { | |
b69a1b40 | 2070 | int ret = notification_thread_command_remove_tracer_event_source( |
352b58f5 JR |
2071 | notification_thread_handle, |
2072 | kernel_tracer_event_notifier_group_notification_fd); | |
2073 | if (ret != LTTNG_OK) { | |
2074 | ERR("Failed to remove kernel event notifier notification from notification thread"); | |
2075 | } | |
2076 | ||
2077 | ret = close(kernel_tracer_event_notifier_group_notification_fd); | |
2078 | if (ret) { | |
2079 | PERROR("Failed to close kernel event notifier group notification file descriptor: fd = %d", | |
2080 | kernel_tracer_event_notifier_group_notification_fd); | |
2081 | } | |
2082 | ||
2083 | kernel_tracer_event_notifier_group_notification_fd = -1; | |
2084 | } | |
2085 | ||
2086 | if (kernel_token_to_event_notifier_rule_ht) { | |
b69a1b40 JG |
2087 | const int ret = cds_lfht_destroy( |
2088 | kernel_token_to_event_notifier_rule_ht, NULL); | |
352b58f5 JR |
2089 | assert(ret == 0); |
2090 | } | |
2091 | ||
2092 | DBG2("Closing kernel event notifier group file descriptor"); | |
2093 | if (kernel_tracer_event_notifier_group_fd >= 0) { | |
b69a1b40 JG |
2094 | const int ret = close(kernel_tracer_event_notifier_group_fd); |
2095 | ||
352b58f5 JR |
2096 | if (ret) { |
2097 | PERROR("Failed to close kernel event notifier group file descriptor: fd = %d", | |
2098 | kernel_tracer_event_notifier_group_fd); | |
2099 | } | |
2100 | ||
2101 | kernel_tracer_event_notifier_group_fd = -1; | |
2102 | } | |
7d268848 MD |
2103 | |
2104 | DBG2("Closing kernel fd"); | |
2105 | if (kernel_tracer_fd >= 0) { | |
b69a1b40 JG |
2106 | const int ret = close(kernel_tracer_fd); |
2107 | ||
7d268848 | 2108 | if (ret) { |
352b58f5 JR |
2109 | PERROR("Failed to close kernel tracer file descriptor: fd = %d", |
2110 | kernel_tracer_fd); | |
7d268848 | 2111 | } |
352b58f5 | 2112 | |
7d268848 MD |
2113 | kernel_tracer_fd = -1; |
2114 | } | |
352b58f5 | 2115 | |
7d268848 MD |
2116 | DBG("Unloading kernel modules"); |
2117 | modprobe_remove_lttng_all(); | |
2118 | free(syscall_table); | |
2119 | } | |
2120 | ||
2121 | LTTNG_HIDDEN | |
2122 | bool kernel_tracer_is_initialized(void) | |
2123 | { | |
2124 | return kernel_tracer_fd >= 0; | |
2125 | } | |
bca212a2 MD |
2126 | |
2127 | /* | |
2128 | * Clear a kernel session. | |
2129 | * | |
2130 | * Return LTTNG_OK on success or else an LTTng error code. | |
2131 | */ | |
2132 | enum lttng_error_code kernel_clear_session(struct ltt_session *session) | |
2133 | { | |
2134 | int ret; | |
2135 | enum lttng_error_code status = LTTNG_OK; | |
2136 | struct consumer_socket *socket; | |
2137 | struct lttng_ht_iter iter; | |
2138 | struct ltt_kernel_session *ksess = session->kernel_session; | |
2139 | ||
2140 | assert(ksess); | |
2141 | assert(ksess->consumer); | |
2142 | ||
2143 | DBG("Clear kernel session %s (session %" PRIu64 ")", | |
2144 | session->name, session->id); | |
2145 | ||
2146 | rcu_read_lock(); | |
2147 | ||
2148 | if (ksess->active) { | |
2149 | ERR("Expecting inactive session %s (%" PRIu64 ")", session->name, session->id); | |
2150 | status = LTTNG_ERR_FATAL; | |
2151 | goto end; | |
2152 | } | |
2153 | ||
2154 | /* | |
2155 | * Note that this loop will end after one iteration given that there is | |
2156 | * only one kernel consumer. | |
2157 | */ | |
2158 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
2159 | socket, node.node) { | |
2160 | struct ltt_kernel_channel *chan; | |
2161 | ||
2162 | /* For each channel, ask the consumer to clear it. */ | |
2163 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
2164 | DBG("Clear kernel channel %" PRIu64 ", session %s", | |
2165 | chan->key, session->name); | |
2166 | ret = consumer_clear_channel(socket, chan->key); | |
2167 | if (ret < 0) { | |
2168 | goto error; | |
2169 | } | |
2170 | } | |
2171 | ||
2172 | if (!ksess->metadata) { | |
2173 | /* | |
2174 | * Nothing to do for the metadata. | |
2175 | * This is a snapshot session. | |
2176 | * The metadata is genererated on the fly. | |
2177 | */ | |
2178 | continue; | |
2179 | } | |
2180 | ||
2181 | /* | |
2182 | * Clear the metadata channel. | |
2183 | * Metadata channel is not cleared per se but we still need to | |
2184 | * perform a rotation operation on it behind the scene. | |
2185 | */ | |
2186 | ret = consumer_clear_channel(socket, ksess->metadata->key); | |
2187 | if (ret < 0) { | |
2188 | goto error; | |
2189 | } | |
2190 | } | |
2191 | ||
2192 | goto end; | |
2193 | error: | |
2194 | switch (-ret) { | |
2195 | case LTTCOMM_CONSUMERD_RELAYD_CLEAR_DISALLOWED: | |
2196 | status = LTTNG_ERR_CLEAR_RELAY_DISALLOWED; | |
2197 | break; | |
2198 | default: | |
2199 | status = LTTNG_ERR_CLEAR_FAIL_CONSUMER; | |
2200 | break; | |
2201 | } | |
2202 | end: | |
2203 | rcu_read_unlock(); | |
2204 | return status; | |
2205 | } | |
352b58f5 JR |
2206 | |
2207 | enum lttng_error_code kernel_create_event_notifier_group_notification_fd( | |
2208 | int *event_notifier_group_notification_fd) | |
2209 | { | |
2210 | int local_fd = -1, ret; | |
2211 | enum lttng_error_code error_code_ret; | |
2212 | ||
2213 | assert(event_notifier_group_notification_fd); | |
2214 | ||
2215 | ret = kernctl_create_event_notifier_group_notification_fd( | |
2216 | kernel_tracer_event_notifier_group_fd); | |
2217 | if (ret < 0) { | |
2218 | PERROR("Failed to create kernel event notifier group notification file descriptor"); | |
2219 | error_code_ret = LTTNG_ERR_EVENT_NOTIFIER_GROUP_NOTIFICATION_FD; | |
2220 | goto error; | |
2221 | } | |
2222 | ||
2223 | local_fd = ret; | |
2224 | ||
2225 | /* Prevent fd duplication after execlp(). */ | |
2226 | ret = fcntl(local_fd, F_SETFD, FD_CLOEXEC); | |
2227 | if (ret < 0) { | |
2228 | PERROR("Failed to set FD_CLOEXEC on kernel event notifier group notification file descriptor: fd = %d", | |
2229 | local_fd); | |
2230 | error_code_ret = LTTNG_ERR_EVENT_NOTIFIER_GROUP_NOTIFICATION_FD; | |
2231 | goto error; | |
2232 | } | |
2233 | ||
2234 | DBG("Created kernel notifier group notification file descriptor: fd = %d", | |
2235 | local_fd); | |
2236 | error_code_ret = LTTNG_OK; | |
2237 | *event_notifier_group_notification_fd = local_fd; | |
2238 | local_fd = -1; | |
2239 | ||
2240 | error: | |
2241 | if (local_fd >= 0) { | |
2242 | ret = close(local_fd); | |
2243 | if (ret) { | |
2244 | PERROR("Failed to close kernel event notifier group notification file descriptor: fd = %d", | |
2245 | local_fd); | |
2246 | } | |
2247 | } | |
2248 | ||
2249 | return error_code_ret; | |
2250 | } | |
2251 | ||
2252 | enum lttng_error_code kernel_destroy_event_notifier_group_notification_fd( | |
2253 | int event_notifier_group_notification_fd) | |
2254 | { | |
2255 | enum lttng_error_code ret_code = LTTNG_OK; | |
2256 | ||
2257 | DBG("Closing event notifier group notification file descriptor: fd = %d", | |
2258 | event_notifier_group_notification_fd); | |
2259 | if (event_notifier_group_notification_fd >= 0) { | |
2260 | const int ret = close(event_notifier_group_notification_fd); | |
2261 | if (ret) { | |
2262 | PERROR("Failed to close event notifier group notification file descriptor: fd = %d", | |
2263 | event_notifier_group_notification_fd); | |
2264 | } | |
2265 | } | |
2266 | ||
2267 | return ret_code; | |
2268 | } | |
2269 | ||
2270 | static | |
2271 | unsigned long hash_trigger(const struct lttng_trigger *trigger) | |
2272 | { | |
2273 | const struct lttng_condition *condition = | |
2274 | lttng_trigger_get_const_condition(trigger); | |
2275 | ||
2276 | return lttng_condition_hash(condition); | |
2277 | } | |
2278 | ||
2279 | static | |
2280 | int match_trigger(struct cds_lfht_node *node, const void *key) | |
2281 | { | |
2282 | const struct ltt_kernel_event_notifier_rule *event_notifier_rule; | |
2283 | const struct lttng_trigger *trigger = key; | |
2284 | ||
2285 | event_notifier_rule = caa_container_of(node, | |
2286 | const struct ltt_kernel_event_notifier_rule, ht_node); | |
2287 | ||
2288 | return lttng_trigger_is_equal(trigger, event_notifier_rule->trigger); | |
2289 | } | |
2290 | ||
2291 | static enum lttng_error_code kernel_create_event_notifier_rule( | |
2292 | struct lttng_trigger *trigger, | |
2293 | const struct lttng_credentials *creds, uint64_t token) | |
2294 | { | |
2295 | int err, fd, ret = 0; | |
2296 | enum lttng_error_code error_code_ret; | |
2297 | enum lttng_condition_status condition_status; | |
2298 | enum lttng_condition_type condition_type; | |
2299 | enum lttng_event_rule_type event_rule_type; | |
2300 | struct ltt_kernel_event_notifier_rule *event_notifier_rule; | |
2301 | struct lttng_kernel_event_notifier kernel_event_notifier = {}; | |
2302 | const struct lttng_condition *condition = NULL; | |
2303 | const struct lttng_event_rule *event_rule = NULL; | |
2304 | ||
2305 | assert(trigger); | |
2306 | ||
2307 | condition = lttng_trigger_get_const_condition(trigger); | |
2308 | assert(condition); | |
2309 | ||
2310 | condition_type = lttng_condition_get_type(condition); | |
2311 | assert(condition_type == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT); | |
2312 | ||
2313 | /* Does not acquire a reference. */ | |
2314 | condition_status = lttng_condition_event_rule_get_rule( | |
2315 | condition, &event_rule); | |
2316 | assert(condition_status == LTTNG_CONDITION_STATUS_OK); | |
2317 | assert(event_rule); | |
2318 | ||
2319 | event_rule_type = lttng_event_rule_get_type(event_rule); | |
2320 | assert(event_rule_type != LTTNG_EVENT_RULE_TYPE_UNKNOWN); | |
2321 | ||
2322 | error_code_ret = trace_kernel_create_event_notifier_rule(trigger, token, | |
2323 | &event_notifier_rule); | |
2324 | if (error_code_ret != LTTNG_OK) { | |
2325 | goto error; | |
2326 | } | |
2327 | ||
2328 | error_code_ret = trace_kernel_init_event_notifier_from_event_rule( | |
2329 | event_rule, &kernel_event_notifier); | |
2330 | if (error_code_ret != LTTNG_OK) { | |
b5e3b044 | 2331 | goto free_event; |
352b58f5 JR |
2332 | } |
2333 | ||
2334 | kernel_event_notifier.event.token = event_notifier_rule->token; | |
2335 | ||
2336 | fd = kernctl_create_event_notifier( | |
2337 | kernel_tracer_event_notifier_group_fd, | |
2338 | &kernel_event_notifier); | |
2339 | if (fd < 0) { | |
2340 | switch (-fd) { | |
2341 | case EEXIST: | |
2342 | error_code_ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
2343 | break; | |
2344 | case ENOSYS: | |
2345 | WARN("Failed to create kernel event notifier: not notifier type not implemented"); | |
2346 | error_code_ret = LTTNG_ERR_KERN_EVENT_ENOSYS; | |
2347 | break; | |
2348 | case ENOENT: | |
2349 | WARN("Failed to create kernel event notifier: not found: name = '%s'", | |
2350 | kernel_event_notifier.event.name); | |
2351 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
2352 | break; | |
2353 | default: | |
2354 | PERROR("Failed to create kernel event notifier: error code = %d, name = '%s'", | |
2355 | fd, kernel_event_notifier.event.name); | |
2356 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
2357 | } | |
2358 | goto free_event; | |
2359 | } | |
2360 | ||
2361 | event_notifier_rule->fd = fd; | |
2362 | /* Prevent fd duplication after execlp(). */ | |
2363 | err = fcntl(event_notifier_rule->fd, F_SETFD, FD_CLOEXEC); | |
2364 | if (err < 0) { | |
2365 | PERROR("Failed to set FD_CLOEXEC on kernel event notifier file descriptor: fd = %d", | |
2366 | fd); | |
2367 | error_code_ret = LTTNG_ERR_FATAL; | |
2368 | goto set_cloexec_error; | |
2369 | } | |
2370 | ||
2371 | if (event_notifier_rule->filter) { | |
2372 | err = kernctl_filter(event_notifier_rule->fd, event_notifier_rule->filter); | |
2373 | if (err < 0) { | |
2374 | switch (-err) { | |
2375 | case ENOMEM: | |
2376 | error_code_ret = LTTNG_ERR_FILTER_NOMEM; | |
2377 | break; | |
2378 | default: | |
2379 | error_code_ret = LTTNG_ERR_FILTER_INVAL; | |
2380 | break; | |
2381 | } | |
2382 | goto filter_error; | |
2383 | } | |
2384 | } | |
2385 | ||
2386 | if (lttng_event_rule_get_type(event_rule) == | |
2387 | LTTNG_EVENT_RULE_TYPE_UPROBE) { | |
2388 | ret = userspace_probe_event_rule_add_callsites( | |
2389 | event_rule, creds, event_notifier_rule->fd); | |
2390 | if (ret) { | |
2391 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
2392 | goto add_callsite_error; | |
2393 | } | |
2394 | } | |
2395 | ||
2396 | err = kernctl_enable(event_notifier_rule->fd); | |
2397 | if (err < 0) { | |
2398 | switch (-err) { | |
2399 | case EEXIST: | |
2400 | error_code_ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
2401 | break; | |
2402 | default: | |
2403 | PERROR("enable kernel event notifier"); | |
2404 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
2405 | break; | |
2406 | } | |
2407 | goto enable_error; | |
2408 | } | |
2409 | ||
2410 | /* Add trigger to kernel token mapping in the hash table. */ | |
2411 | rcu_read_lock(); | |
2412 | cds_lfht_add(kernel_token_to_event_notifier_rule_ht, hash_trigger(trigger), | |
2413 | &event_notifier_rule->ht_node); | |
2414 | rcu_read_unlock(); | |
2415 | ||
2416 | DBG("Created kernel event notifier: name = '%s', fd = %d", | |
2417 | kernel_event_notifier.event.name, | |
2418 | event_notifier_rule->fd); | |
2419 | ||
2420 | return LTTNG_OK; | |
2421 | ||
2422 | add_callsite_error: | |
2423 | enable_error: | |
2424 | set_cloexec_error: | |
2425 | filter_error: | |
2426 | { | |
2427 | const int close_ret = close(event_notifier_rule->fd); | |
2428 | ||
2429 | if (close_ret) { | |
2430 | PERROR("Failed to close kernel event notifier file descriptor: fd = %d", | |
2431 | event_notifier_rule->fd); | |
2432 | } | |
2433 | } | |
2434 | free_event: | |
2435 | free(event_notifier_rule); | |
2436 | error: | |
2437 | return error_code_ret; | |
2438 | } | |
2439 | ||
2440 | enum lttng_error_code kernel_register_event_notifier( | |
2441 | struct lttng_trigger *trigger, | |
2442 | const struct lttng_credentials *cmd_creds) | |
2443 | { | |
2444 | enum lttng_error_code ret; | |
2445 | enum lttng_condition_status status; | |
2446 | enum lttng_domain_type domain_type; | |
2447 | const struct lttng_event_rule *event_rule; | |
2448 | const struct lttng_condition *const condition = | |
2449 | lttng_trigger_get_const_condition(trigger); | |
2450 | const uint64_t token = lttng_trigger_get_tracer_token(trigger); | |
2451 | ||
2452 | assert(condition); | |
2453 | ||
2454 | /* Does not acquire a reference to the event rule. */ | |
2455 | status = lttng_condition_event_rule_get_rule( | |
2456 | condition, &event_rule); | |
2457 | assert(status == LTTNG_CONDITION_STATUS_OK); | |
2458 | ||
2459 | domain_type = lttng_event_rule_get_domain_type(event_rule); | |
2460 | assert(domain_type == LTTNG_DOMAIN_KERNEL); | |
2461 | ||
2462 | ret = kernel_create_event_notifier_rule(trigger, cmd_creds, token); | |
2463 | if (ret != LTTNG_OK) { | |
124dda43 | 2464 | ERR("Failed to create kernel event notifier rule"); |
352b58f5 JR |
2465 | } |
2466 | ||
2467 | return ret; | |
2468 | } | |
2469 | ||
2470 | enum lttng_error_code kernel_unregister_event_notifier( | |
2471 | const struct lttng_trigger *trigger) | |
2472 | { | |
2473 | struct ltt_kernel_event_notifier_rule *token_event_rule_element; | |
2474 | struct cds_lfht_node *node; | |
2475 | struct cds_lfht_iter iter; | |
2476 | enum lttng_error_code error_code_ret; | |
2477 | int ret; | |
2478 | ||
2479 | rcu_read_lock(); | |
2480 | ||
2481 | cds_lfht_lookup(kernel_token_to_event_notifier_rule_ht, | |
2482 | hash_trigger(trigger), match_trigger, trigger, &iter); | |
2483 | ||
2484 | node = cds_lfht_iter_get_node(&iter); | |
2485 | if (!node) { | |
2486 | error_code_ret = LTTNG_ERR_TRIGGER_NOT_FOUND; | |
2487 | goto error; | |
2488 | } | |
2489 | ||
2490 | token_event_rule_element = caa_container_of(node, | |
2491 | struct ltt_kernel_event_notifier_rule, ht_node); | |
2492 | ||
2493 | ret = kernel_disable_event_notifier_rule(token_event_rule_element); | |
2494 | if (ret) { | |
2495 | error_code_ret = LTTNG_ERR_FATAL; | |
2496 | goto error; | |
2497 | } | |
2498 | ||
2499 | trace_kernel_destroy_event_notifier_rule(token_event_rule_element); | |
2500 | error_code_ret = LTTNG_OK; | |
2501 | ||
2502 | error: | |
2503 | rcu_read_unlock(); | |
2504 | ||
2505 | return error_code_ret; | |
2506 | } | |
2507 | ||
2508 | int kernel_get_notification_fd(void) | |
2509 | { | |
2510 | return kernel_tracer_event_notifier_group_notification_fd; | |
2511 | } |