Commit | Line | Data |
---|---|---|
20fe2104 | 1 | /* |
21cf9b6b | 2 | * Copyright (C) 2011 EfficiOS Inc. |
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 | |
c9e313bc SM |
17 | #include <common/common.hpp> |
18 | #include <common/hashtable/utils.hpp> | |
19 | #include <common/trace-chunk.hpp> | |
20 | #include <common/kernel-ctl/kernel-ctl.hpp> | |
21 | #include <common/kernel-ctl/kernel-ioctl.hpp> | |
22 | #include <common/sessiond-comm/sessiond-comm.hpp> | |
23 | #include <common/tracker.hpp> | |
24 | #include <common/utils.hpp> | |
c5bf436c JG |
25 | #include <lttng/event.h> |
26 | #include <lttng/lttng-error.h> | |
27 | #include <lttng/tracker.h> | |
1e307fab | 28 | |
352b58f5 | 29 | #include <lttng/userspace-probe.h> |
c9e313bc | 30 | #include <lttng/userspace-probe-internal.hpp> |
670a26e4 | 31 | #include <lttng/condition/event-rule-matches.h> |
c9e313bc | 32 | #include <lttng/condition/event-rule-matches-internal.hpp> |
352b58f5 | 33 | #include <lttng/event-rule/event-rule.h> |
c9e313bc SM |
34 | #include <lttng/event-rule/event-rule-internal.hpp> |
35 | #include <lttng/event-rule/kernel-uprobe-internal.hpp> | |
352b58f5 | 36 | |
c9e313bc SM |
37 | #include "event-notifier-error-accounting.hpp" |
38 | #include "lttng-sessiond.hpp" | |
39 | #include "lttng-syscall.hpp" | |
40 | #include "condition-internal.hpp" | |
41 | #include "consumer.hpp" | |
42 | #include "kernel.hpp" | |
43 | #include "kernel-consumer.hpp" | |
44 | #include "kern-modules.hpp" | |
45 | #include "sessiond-config.hpp" | |
46 | #include "utils.hpp" | |
47 | #include "rotate.hpp" | |
48 | #include "modprobe.hpp" | |
49 | #include "tracker.hpp" | |
50 | #include "notification-thread-commands.hpp" | |
20fe2104 | 51 | |
e1f3997a JD |
52 | /* |
53 | * Key used to reference a channel between the sessiond and the consumer. This | |
54 | * is only read and updated with the session_list lock held. | |
55 | */ | |
56 | static uint64_t next_kernel_channel_key; | |
57 | ||
7d268848 MD |
58 | static const char *module_proc_lttng = "/proc/lttng"; |
59 | ||
60 | static int kernel_tracer_fd = -1; | |
352b58f5 JR |
61 | static int kernel_tracer_event_notifier_group_fd = -1; |
62 | static int kernel_tracer_event_notifier_group_notification_fd = -1; | |
63 | static struct cds_lfht *kernel_token_to_event_notifier_rule_ht; | |
7d268848 | 64 | |
d65106b1 | 65 | /* |
050349bb | 66 | * Add context on a kernel channel. |
df3c77c8 JG |
67 | * |
68 | * Assumes the ownership of ctx. | |
d65106b1 DG |
69 | */ |
70 | int kernel_add_channel_context(struct ltt_kernel_channel *chan, | |
645328ae | 71 | struct ltt_kernel_context *ctx) |
d65106b1 DG |
72 | { |
73 | int ret; | |
74 | ||
a0377dfe FD |
75 | LTTNG_ASSERT(chan); |
76 | LTTNG_ASSERT(ctx); | |
0525e9ae | 77 | |
d65106b1 | 78 | DBG("Adding context to channel %s", chan->channel->name); |
645328ae | 79 | ret = kernctl_add_context(chan->fd, &ctx->ctx); |
d65106b1 | 80 | if (ret < 0) { |
32af2c95 | 81 | switch (-ret) { |
1ae5e83e JD |
82 | case ENOSYS: |
83 | /* Exists but not available for this kernel */ | |
84 | ret = LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE; | |
85 | goto error; | |
86 | case EEXIST: | |
b579acd9 DG |
87 | /* If EEXIST, we just ignore the error */ |
88 | ret = 0; | |
1ae5e83e JD |
89 | goto end; |
90 | default: | |
91 | PERROR("add context ioctl"); | |
92 | ret = LTTNG_ERR_KERN_CONTEXT_FAIL; | |
93 | goto error; | |
b579acd9 | 94 | } |
d65106b1 | 95 | } |
21ed98c1 | 96 | ret = 0; |
d65106b1 | 97 | |
1ae5e83e | 98 | end: |
645328ae | 99 | cds_list_add_tail(&ctx->list, &chan->ctx_list); |
ba985c3a | 100 | ctx->in_list = true; |
df3c77c8 | 101 | ctx = NULL; |
d65106b1 | 102 | error: |
df3c77c8 JG |
103 | if (ctx) { |
104 | trace_kernel_destroy_context(ctx); | |
105 | } | |
d65106b1 DG |
106 | return ret; |
107 | } | |
108 | ||
20fe2104 | 109 | /* |
050349bb DG |
110 | * Create a new kernel session, register it to the kernel tracer and add it to |
111 | * the session daemon session. | |
20fe2104 | 112 | */ |
7d268848 | 113 | int kernel_create_session(struct ltt_session *session) |
20fe2104 DG |
114 | { |
115 | int ret; | |
116 | struct ltt_kernel_session *lks; | |
117 | ||
a0377dfe | 118 | LTTNG_ASSERT(session); |
0525e9ae | 119 | |
54012638 | 120 | /* Allocate data structure */ |
0e1fd1e8 JR |
121 | lks = trace_kernel_create_session( |
122 | std::const_pointer_cast<const lttng::trace_format_descriptor>( | |
123 | session->trace_format)); | |
20fe2104 | 124 | if (lks == NULL) { |
54012638 | 125 | ret = -1; |
20fe2104 DG |
126 | goto error; |
127 | } | |
128 | ||
54012638 | 129 | /* Kernel tracer session creation */ |
7d268848 | 130 | ret = kernctl_create_session(kernel_tracer_fd); |
20fe2104 | 131 | if (ret < 0) { |
df0f840b | 132 | PERROR("ioctl kernel create session"); |
20fe2104 DG |
133 | goto error; |
134 | } | |
135 | ||
20fe2104 | 136 | lks->fd = ret; |
7b395890 DG |
137 | /* Prevent fd duplication after execlp() */ |
138 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
139 | if (ret < 0) { | |
df0f840b | 140 | PERROR("fcntl session fd"); |
7b395890 DG |
141 | } |
142 | ||
53632229 | 143 | lks->id = session->id; |
3bd1e081 | 144 | lks->consumer_fds_sent = 0; |
8c0faa1d | 145 | session->kernel_session = lks; |
8c0faa1d DG |
146 | |
147 | DBG("Kernel session created (fd: %d)", lks->fd); | |
20fe2104 | 148 | |
8ff4109e JR |
149 | /* |
150 | * This is necessary since the creation time is present in the session | |
151 | * name when it is generated. | |
152 | */ | |
153 | if (session->has_auto_generated_name) { | |
154 | ret = kernctl_session_set_name(lks->fd, DEFAULT_SESSION_NAME); | |
155 | } else { | |
156 | ret = kernctl_session_set_name(lks->fd, session->name); | |
157 | } | |
158 | if (ret) { | |
159 | WARN("Could not set kernel session name for session %" PRIu64 " name: %s", | |
160 | session->id, session->name); | |
161 | } | |
162 | ||
e04b2181 JR |
163 | ret = kernctl_session_set_creation_time(lks->fd, session->creation_time); |
164 | if (ret) { | |
165 | WARN("Could not set kernel session creation time for session %" PRIu64 " name: %s", | |
166 | session->id, session->name); | |
167 | } | |
168 | ||
121b0d1a JR |
169 | ret = kernctl_session_set_trace_format(lks->fd, *session->trace_format); |
170 | if (ret) { | |
171 | WARN("Could not set kernel session trace format %" PRIu64 " name: %s", session->id, | |
172 | session->name); | |
173 | } | |
20fe2104 DG |
174 | return 0; |
175 | ||
176 | error: | |
5f62c685 DG |
177 | if (lks) { |
178 | trace_kernel_destroy_session(lks); | |
d070c424 | 179 | trace_kernel_free_session(lks); |
5f62c685 | 180 | } |
20fe2104 DG |
181 | return ret; |
182 | } | |
183 | ||
184 | /* | |
050349bb DG |
185 | * Create a kernel channel, register it to the kernel tracer and add it to the |
186 | * kernel session. | |
20fe2104 | 187 | */ |
050349bb | 188 | int kernel_create_channel(struct ltt_kernel_session *session, |
fdd9eb17 | 189 | struct lttng_channel *chan) |
20fe2104 DG |
190 | { |
191 | int ret; | |
192 | struct ltt_kernel_channel *lkc; | |
20fe2104 | 193 | |
a0377dfe FD |
194 | LTTNG_ASSERT(session); |
195 | LTTNG_ASSERT(chan); | |
0525e9ae | 196 | |
54012638 | 197 | /* Allocate kernel channel */ |
fdd9eb17 | 198 | lkc = trace_kernel_create_channel(chan); |
54012638 | 199 | if (lkc == NULL) { |
20fe2104 DG |
200 | goto error; |
201 | } | |
202 | ||
ecc48a90 | 203 | DBG3("Kernel create channel %s with attr: %d, %" PRIu64 ", %" PRIu64 ", %u, %u, %d, %d", |
fdd9eb17 | 204 | chan->name, lkc->channel->attr.overwrite, |
173af62f DG |
205 | lkc->channel->attr.subbuf_size, lkc->channel->attr.num_subbuf, |
206 | lkc->channel->attr.switch_timer_interval, lkc->channel->attr.read_timer_interval, | |
ecc48a90 | 207 | lkc->channel->attr.live_timer_interval, lkc->channel->attr.output); |
173af62f | 208 | |
54012638 | 209 | /* Kernel tracer channel creation */ |
f3ed775e | 210 | ret = kernctl_create_channel(session->fd, &lkc->channel->attr); |
20fe2104 | 211 | if (ret < 0) { |
df0f840b | 212 | PERROR("ioctl kernel create channel"); |
20fe2104 DG |
213 | goto error; |
214 | } | |
215 | ||
54012638 | 216 | /* Setup the channel fd */ |
20fe2104 | 217 | lkc->fd = ret; |
7b395890 DG |
218 | /* Prevent fd duplication after execlp() */ |
219 | ret = fcntl(lkc->fd, F_SETFD, FD_CLOEXEC); | |
220 | if (ret < 0) { | |
df0f840b | 221 | PERROR("fcntl session fd"); |
7b395890 DG |
222 | } |
223 | ||
54012638 | 224 | /* Add channel to session */ |
8c0faa1d DG |
225 | cds_list_add(&lkc->list, &session->channel_list.head); |
226 | session->channel_count++; | |
fb5f35b6 | 227 | lkc->session = session; |
e1f3997a | 228 | lkc->key = ++next_kernel_channel_key; |
20fe2104 | 229 | |
e1f3997a JD |
230 | DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")", |
231 | lkc->channel->name, lkc->fd, lkc->key); | |
20fe2104 DG |
232 | |
233 | return 0; | |
234 | ||
235 | error: | |
5f62c685 DG |
236 | if (lkc) { |
237 | free(lkc->channel); | |
238 | free(lkc); | |
239 | } | |
54012638 | 240 | return -1; |
20fe2104 | 241 | } |
f34daff7 | 242 | |
352b58f5 JR |
243 | /* |
244 | * Create a kernel event notifier group, register it to the kernel tracer and | |
245 | * add it to the kernel session. | |
246 | */ | |
247 | static int kernel_create_event_notifier_group(int *event_notifier_group_fd) | |
248 | { | |
249 | int ret; | |
250 | int local_fd = -1; | |
251 | ||
a0377dfe | 252 | LTTNG_ASSERT(event_notifier_group_fd); |
352b58f5 JR |
253 | |
254 | /* Kernel event notifier group creation. */ | |
255 | ret = kernctl_create_event_notifier_group(kernel_tracer_fd); | |
256 | if (ret < 0) { | |
257 | PERROR("Failed to create kernel event notifier group"); | |
258 | ret = -1; | |
259 | goto error; | |
260 | } | |
261 | ||
262 | local_fd = ret; | |
263 | ||
264 | /* Prevent fd duplication after execlp(). */ | |
265 | ret = fcntl(local_fd, F_SETFD, FD_CLOEXEC); | |
266 | if (ret < 0) { | |
267 | PERROR("Failed to set FD_CLOEXEC on kernel event notifier group file descriptor: fd = %d", | |
268 | local_fd); | |
269 | goto error; | |
270 | } | |
271 | ||
272 | DBG("Created kernel event notifier group: fd = %d", local_fd); | |
273 | *event_notifier_group_fd = local_fd; | |
274 | local_fd = -1; | |
275 | ret = 0; | |
276 | error: | |
277 | if (local_fd >= 0) { | |
278 | ret = close(local_fd); | |
279 | if (ret) { | |
280 | PERROR("Failed to close kernel event notifier group file descriptor: fd = %d", | |
281 | local_fd); | |
282 | } | |
283 | } | |
284 | ||
285 | return ret; | |
286 | } | |
287 | ||
410b78a0 FD |
288 | /* |
289 | * Compute the offset of the instrumentation byte in the binary based on the | |
290 | * function probe location using the ELF lookup method. | |
291 | * | |
292 | * Returns 0 on success and set the offset out parameter to the offset of the | |
293 | * elf symbol | |
294 | * Returns -1 on error | |
295 | */ | |
296 | static | |
297 | int extract_userspace_probe_offset_function_elf( | |
87597c2c | 298 | const struct lttng_userspace_probe_location *probe_location, |
0a398bc4 | 299 | uid_t uid, gid_t gid, uint64_t *offset) |
410b78a0 FD |
300 | { |
301 | int fd; | |
302 | int ret = 0; | |
303 | const char *symbol = NULL; | |
87597c2c | 304 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
305 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; |
306 | ||
a0377dfe | 307 | LTTNG_ASSERT(lttng_userspace_probe_location_get_type(probe_location) == |
410b78a0 FD |
308 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_FUNCTION); |
309 | ||
310 | lookup = lttng_userspace_probe_location_get_lookup_method( | |
311 | probe_location); | |
312 | if (!lookup) { | |
313 | ret = -1; | |
314 | goto end; | |
315 | } | |
316 | ||
317 | lookup_method_type = | |
318 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
319 | ||
a0377dfe | 320 | LTTNG_ASSERT(lookup_method_type == |
410b78a0 FD |
321 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF); |
322 | ||
323 | symbol = lttng_userspace_probe_location_function_get_function_name( | |
324 | probe_location); | |
325 | if (!symbol) { | |
326 | ret = -1; | |
327 | goto end; | |
328 | } | |
329 | ||
330 | fd = lttng_userspace_probe_location_function_get_binary_fd(probe_location); | |
331 | if (fd < 0) { | |
332 | ret = -1; | |
333 | goto end; | |
334 | } | |
335 | ||
0a398bc4 | 336 | ret = run_as_extract_elf_symbol_offset(fd, symbol, uid, gid, offset); |
410b78a0 FD |
337 | if (ret < 0) { |
338 | DBG("userspace probe offset calculation failed for " | |
339 | "function %s", symbol); | |
340 | goto end; | |
341 | } | |
342 | ||
343 | DBG("userspace probe elf offset for %s is 0x%jd", symbol, (intmax_t)(*offset)); | |
344 | end: | |
345 | return ret; | |
346 | } | |
347 | ||
348 | /* | |
349 | * Compute the offsets of the instrumentation bytes in the binary based on the | |
350 | * tracepoint probe location using the SDT lookup method. This function | |
351 | * allocates the offsets buffer, the caller must free it. | |
352 | * | |
353 | * Returns 0 on success and set the offset out parameter to the offsets of the | |
354 | * SDT tracepoint. | |
355 | * Returns -1 on error. | |
356 | */ | |
357 | static | |
358 | int extract_userspace_probe_offset_tracepoint_sdt( | |
87597c2c | 359 | const struct lttng_userspace_probe_location *probe_location, |
0a398bc4 | 360 | uid_t uid, gid_t gid, uint64_t **offsets, |
410b78a0 FD |
361 | uint32_t *offsets_count) |
362 | { | |
363 | enum lttng_userspace_probe_location_lookup_method_type lookup_method_type; | |
87597c2c | 364 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
410b78a0 FD |
365 | const char *probe_name = NULL, *provider_name = NULL; |
366 | int ret = 0; | |
367 | int fd, i; | |
368 | ||
a0377dfe | 369 | LTTNG_ASSERT(lttng_userspace_probe_location_get_type(probe_location) == |
410b78a0 FD |
370 | LTTNG_USERSPACE_PROBE_LOCATION_TYPE_TRACEPOINT); |
371 | ||
372 | lookup = lttng_userspace_probe_location_get_lookup_method(probe_location); | |
373 | if (!lookup) { | |
374 | ret = -1; | |
375 | goto end; | |
376 | } | |
377 | ||
378 | lookup_method_type = | |
379 | lttng_userspace_probe_location_lookup_method_get_type(lookup); | |
380 | ||
a0377dfe | 381 | LTTNG_ASSERT(lookup_method_type == |
410b78a0 FD |
382 | LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT); |
383 | ||
384 | ||
385 | probe_name = lttng_userspace_probe_location_tracepoint_get_probe_name( | |
386 | probe_location); | |
387 | if (!probe_name) { | |
388 | ret = -1; | |
389 | goto end; | |
390 | } | |
391 | ||
392 | provider_name = lttng_userspace_probe_location_tracepoint_get_provider_name( | |
393 | probe_location); | |
394 | if (!provider_name) { | |
395 | ret = -1; | |
396 | goto end; | |
397 | } | |
398 | ||
399 | fd = lttng_userspace_probe_location_tracepoint_get_binary_fd(probe_location); | |
400 | if (fd < 0) { | |
401 | ret = -1; | |
402 | goto end; | |
403 | } | |
404 | ||
405 | ret = run_as_extract_sdt_probe_offsets(fd, provider_name, probe_name, | |
0a398bc4 | 406 | uid, gid, offsets, offsets_count); |
410b78a0 FD |
407 | if (ret < 0) { |
408 | DBG("userspace probe offset calculation failed for sdt " | |
409 | "probe %s:%s", provider_name, probe_name); | |
410 | goto end; | |
411 | } | |
412 | ||
413 | if (*offsets_count == 0) { | |
414 | DBG("no userspace probe offset found"); | |
415 | goto end; | |
416 | } | |
417 | ||
418 | DBG("%u userspace probe SDT offsets found for %s:%s at:", | |
419 | *offsets_count, provider_name, probe_name); | |
420 | for (i = 0; i < *offsets_count; i++) { | |
421 | DBG("\t0x%jd", (intmax_t)((*offsets)[i])); | |
422 | } | |
423 | end: | |
424 | return ret; | |
425 | } | |
426 | ||
410b78a0 | 427 | static |
0a398bc4 FD |
428 | int userspace_probe_add_callsite( |
429 | const struct lttng_userspace_probe_location *location, | |
430 | uid_t uid, gid_t gid, int fd) | |
410b78a0 | 431 | { |
87597c2c | 432 | const struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL; |
410b78a0 | 433 | enum lttng_userspace_probe_location_lookup_method_type type; |
410b78a0 FD |
434 | int ret; |
435 | ||
0a398bc4 | 436 | lookup_method = lttng_userspace_probe_location_get_lookup_method(location); |
410b78a0 FD |
437 | if (!lookup_method) { |
438 | ret = -1; | |
439 | goto end; | |
440 | } | |
441 | ||
442 | type = lttng_userspace_probe_location_lookup_method_get_type(lookup_method); | |
443 | switch (type) { | |
444 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: | |
445 | { | |
b8e2fb80 | 446 | struct lttng_kernel_abi_event_callsite callsite; |
410b78a0 FD |
447 | uint64_t offset; |
448 | ||
0a398bc4 FD |
449 | ret = extract_userspace_probe_offset_function_elf(location, |
450 | uid, gid, &offset); | |
410b78a0 FD |
451 | if (ret) { |
452 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
453 | goto end; | |
454 | } | |
455 | ||
456 | callsite.u.uprobe.offset = offset; | |
457 | ret = kernctl_add_callsite(fd, &callsite); | |
458 | if (ret) { | |
0a398bc4 | 459 | WARN("Failed to add callsite to ELF userspace probe."); |
410b78a0 FD |
460 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
461 | goto end; | |
462 | } | |
463 | break; | |
464 | } | |
465 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: | |
466 | { | |
467 | int i; | |
468 | uint64_t *offsets = NULL; | |
469 | uint32_t offsets_count; | |
b8e2fb80 | 470 | struct lttng_kernel_abi_event_callsite callsite; |
410b78a0 FD |
471 | |
472 | /* | |
473 | * This call allocates the offsets buffer. This buffer must be freed | |
474 | * by the caller | |
475 | */ | |
0a398bc4 FD |
476 | ret = extract_userspace_probe_offset_tracepoint_sdt(location, |
477 | uid, gid, &offsets, &offsets_count); | |
410b78a0 FD |
478 | if (ret) { |
479 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
480 | goto end; | |
481 | } | |
482 | for (i = 0; i < offsets_count; i++) { | |
483 | callsite.u.uprobe.offset = offsets[i]; | |
484 | ret = kernctl_add_callsite(fd, &callsite); | |
485 | if (ret) { | |
0a398bc4 | 486 | WARN("Failed to add callsite to SDT userspace probe"); |
410b78a0 FD |
487 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
488 | free(offsets); | |
489 | goto end; | |
490 | } | |
491 | } | |
492 | free(offsets); | |
493 | break; | |
494 | } | |
495 | default: | |
496 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; | |
497 | goto end; | |
498 | } | |
499 | end: | |
500 | return ret; | |
501 | } | |
502 | ||
0a398bc4 FD |
503 | /* |
504 | * Extract the offsets of the instrumentation point for the different lookup | |
505 | * methods. | |
506 | */ | |
507 | static | |
508 | int userspace_probe_event_add_callsites(struct lttng_event *ev, | |
509 | struct ltt_kernel_session *session, int fd) | |
510 | { | |
511 | int ret; | |
512 | const struct lttng_userspace_probe_location *location = NULL; | |
513 | ||
a0377dfe FD |
514 | LTTNG_ASSERT(ev); |
515 | LTTNG_ASSERT(ev->type == LTTNG_EVENT_USERSPACE_PROBE); | |
0a398bc4 FD |
516 | |
517 | location = lttng_event_get_userspace_probe_location(ev); | |
518 | if (!location) { | |
519 | ret = -1; | |
520 | goto end; | |
521 | } | |
522 | ||
523 | ret = userspace_probe_add_callsite(location, session->uid, session->gid, | |
524 | fd); | |
525 | if (ret) { | |
526 | WARN("Failed to add callsite to userspace probe event '%s'", | |
527 | ev->name); | |
528 | } | |
529 | ||
530 | end: | |
531 | return ret; | |
532 | } | |
533 | ||
352b58f5 JR |
534 | /* |
535 | * Extract the offsets of the instrumentation point for the different look-up | |
536 | * methods. | |
537 | */ | |
538 | static int userspace_probe_event_rule_add_callsites( | |
539 | const struct lttng_event_rule *rule, | |
540 | const struct lttng_credentials *creds, | |
541 | int fd) | |
542 | { | |
543 | int ret; | |
544 | enum lttng_event_rule_status status; | |
545 | enum lttng_event_rule_type event_rule_type; | |
546 | const struct lttng_userspace_probe_location *location = NULL; | |
547 | ||
a0377dfe FD |
548 | LTTNG_ASSERT(rule); |
549 | LTTNG_ASSERT(creds); | |
352b58f5 JR |
550 | |
551 | event_rule_type = lttng_event_rule_get_type(rule); | |
a0377dfe | 552 | LTTNG_ASSERT(event_rule_type == LTTNG_EVENT_RULE_TYPE_KERNEL_UPROBE); |
352b58f5 | 553 | |
46fd07ac | 554 | status = lttng_event_rule_kernel_uprobe_get_location(rule, &location); |
352b58f5 JR |
555 | if (status != LTTNG_EVENT_RULE_STATUS_OK || !location) { |
556 | ret = -1; | |
557 | goto end; | |
558 | } | |
559 | ||
560 | ret = userspace_probe_add_callsite(location, | |
561 | lttng_credentials_get_uid(creds), | |
562 | lttng_credentials_get_gid(creds), fd); | |
563 | if (ret) { | |
564 | WARN("Failed to add callsite to user space probe object: fd = %d", | |
565 | fd); | |
566 | } | |
567 | ||
568 | end: | |
569 | return ret; | |
570 | } | |
571 | ||
f34daff7 | 572 | /* |
050349bb DG |
573 | * Create a kernel event, enable it to the kernel tracer and add it to the |
574 | * channel event list of the kernel session. | |
49d21f93 | 575 | * We own filter_expression and filter. |
f34daff7 | 576 | */ |
050349bb | 577 | int kernel_create_event(struct lttng_event *ev, |
00a62084 MD |
578 | struct ltt_kernel_channel *channel, |
579 | char *filter_expression, | |
2b00d462 | 580 | struct lttng_bytecode *filter) |
f34daff7 | 581 | { |
71a3bb01 FD |
582 | int err, fd; |
583 | enum lttng_error_code ret; | |
f34daff7 | 584 | struct ltt_kernel_event *event; |
f34daff7 | 585 | |
a0377dfe FD |
586 | LTTNG_ASSERT(ev); |
587 | LTTNG_ASSERT(channel); | |
0525e9ae | 588 | |
a969e101 | 589 | /* We pass ownership of filter_expression and filter */ |
71a3bb01 FD |
590 | ret = trace_kernel_create_event(ev, filter_expression, |
591 | filter, &event); | |
592 | if (ret != LTTNG_OK) { | |
f34daff7 DG |
593 | goto error; |
594 | } | |
595 | ||
71a3bb01 FD |
596 | fd = kernctl_create_event(channel->fd, event->event); |
597 | if (fd < 0) { | |
598 | switch (-fd) { | |
bd29c13d | 599 | case EEXIST: |
71a3bb01 | 600 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
bd29c13d DG |
601 | break; |
602 | case ENOSYS: | |
603 | WARN("Event type not implemented"); | |
71a3bb01 | 604 | ret = LTTNG_ERR_KERN_EVENT_ENOSYS; |
bd29c13d | 605 | break; |
8197a339 DG |
606 | case ENOENT: |
607 | WARN("Event %s not found!", ev->name); | |
71a3bb01 | 608 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
8197a339 | 609 | break; |
bd29c13d | 610 | default: |
71a3bb01 | 611 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
d87bfb32 DG |
612 | PERROR("create event ioctl"); |
613 | } | |
e953ef25 | 614 | goto free_event; |
8c0faa1d | 615 | } |
f34daff7 | 616 | |
d0ae4ea8 | 617 | event->type = ev->type; |
71a3bb01 | 618 | event->fd = fd; |
7b395890 | 619 | /* Prevent fd duplication after execlp() */ |
71a3bb01 FD |
620 | err = fcntl(event->fd, F_SETFD, FD_CLOEXEC); |
621 | if (err < 0) { | |
df0f840b | 622 | PERROR("fcntl session fd"); |
7b395890 DG |
623 | } |
624 | ||
00a62084 | 625 | if (filter) { |
71a3bb01 FD |
626 | err = kernctl_filter(event->fd, filter); |
627 | if (err < 0) { | |
628 | switch (-err) { | |
629 | case ENOMEM: | |
630 | ret = LTTNG_ERR_FILTER_NOMEM; | |
631 | break; | |
632 | default: | |
633 | ret = LTTNG_ERR_FILTER_INVAL; | |
634 | break; | |
635 | } | |
00a62084 MD |
636 | goto filter_error; |
637 | } | |
638 | } | |
639 | ||
dcabc190 | 640 | if (ev->type == LTTNG_EVENT_USERSPACE_PROBE) { |
7966af57 | 641 | ret = (lttng_error_code) userspace_probe_event_add_callsites(ev, channel->session, |
0a398bc4 | 642 | event->fd); |
dcabc190 FD |
643 | if (ret) { |
644 | goto add_callsite_error; | |
645 | } | |
646 | } | |
647 | ||
71a3bb01 FD |
648 | err = kernctl_enable(event->fd); |
649 | if (err < 0) { | |
650 | switch (-err) { | |
00a62084 MD |
651 | case EEXIST: |
652 | ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
653 | break; | |
654 | default: | |
655 | PERROR("enable kernel event"); | |
71a3bb01 | 656 | ret = LTTNG_ERR_KERN_ENABLE_FAIL; |
00a62084 MD |
657 | break; |
658 | } | |
659 | goto enable_error; | |
660 | } | |
661 | ||
f3ed775e DG |
662 | /* Add event to event list */ |
663 | cds_list_add(&event->list, &channel->events_list.head); | |
cbbbb275 DG |
664 | channel->event_count++; |
665 | ||
e953ef25 DG |
666 | DBG("Event %s created (fd: %d)", ev->name, event->fd); |
667 | ||
668 | return 0; | |
669 | ||
dcabc190 | 670 | add_callsite_error: |
00a62084 MD |
671 | enable_error: |
672 | filter_error: | |
673 | { | |
674 | int closeret; | |
675 | ||
676 | closeret = close(event->fd); | |
677 | if (closeret) { | |
678 | PERROR("close event fd"); | |
679 | } | |
680 | } | |
e953ef25 DG |
681 | free_event: |
682 | free(event); | |
683 | error: | |
d87bfb32 | 684 | return ret; |
e953ef25 DG |
685 | } |
686 | ||
26cc6b4e | 687 | /* |
050349bb | 688 | * Disable a kernel channel. |
26cc6b4e DG |
689 | */ |
690 | int kernel_disable_channel(struct ltt_kernel_channel *chan) | |
691 | { | |
692 | int ret; | |
693 | ||
a0377dfe | 694 | LTTNG_ASSERT(chan); |
0525e9ae | 695 | |
26cc6b4e DG |
696 | ret = kernctl_disable(chan->fd); |
697 | if (ret < 0) { | |
df0f840b | 698 | PERROR("disable chan ioctl"); |
26cc6b4e DG |
699 | goto error; |
700 | } | |
701 | ||
702 | chan->enabled = 0; | |
e1f3997a JD |
703 | DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")", |
704 | chan->channel->name, chan->fd, chan->key); | |
26cc6b4e DG |
705 | |
706 | return 0; | |
707 | ||
708 | error: | |
709 | return ret; | |
710 | } | |
711 | ||
d36b8583 | 712 | /* |
050349bb | 713 | * Enable a kernel channel. |
d36b8583 DG |
714 | */ |
715 | int kernel_enable_channel(struct ltt_kernel_channel *chan) | |
716 | { | |
717 | int ret; | |
718 | ||
a0377dfe | 719 | LTTNG_ASSERT(chan); |
0525e9ae | 720 | |
d36b8583 | 721 | ret = kernctl_enable(chan->fd); |
32af2c95 | 722 | if (ret < 0 && ret != -EEXIST) { |
df0f840b | 723 | PERROR("Enable kernel chan"); |
d36b8583 DG |
724 | goto error; |
725 | } | |
726 | ||
727 | chan->enabled = 1; | |
e1f3997a JD |
728 | DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")", |
729 | chan->channel->name, chan->fd, chan->key); | |
d36b8583 DG |
730 | |
731 | return 0; | |
732 | ||
733 | error: | |
734 | return ret; | |
735 | } | |
736 | ||
19e70852 | 737 | /* |
050349bb | 738 | * Enable a kernel event. |
19e70852 DG |
739 | */ |
740 | int kernel_enable_event(struct ltt_kernel_event *event) | |
741 | { | |
742 | int ret; | |
743 | ||
a0377dfe | 744 | LTTNG_ASSERT(event); |
0525e9ae | 745 | |
19e70852 | 746 | ret = kernctl_enable(event->fd); |
42224349 | 747 | if (ret < 0) { |
32af2c95 | 748 | switch (-ret) { |
42224349 | 749 | case EEXIST: |
f73fabfd | 750 | ret = LTTNG_ERR_KERN_EVENT_EXIST; |
42224349 DG |
751 | break; |
752 | default: | |
753 | PERROR("enable kernel event"); | |
754 | break; | |
755 | } | |
19e70852 DG |
756 | goto error; |
757 | } | |
758 | ||
759 | event->enabled = 1; | |
760 | DBG("Kernel event %s enabled (fd: %d)", event->event->name, event->fd); | |
761 | ||
762 | return 0; | |
763 | ||
764 | error: | |
d36b8583 | 765 | return ret; |
19e70852 DG |
766 | } |
767 | ||
e953ef25 | 768 | /* |
050349bb | 769 | * Disable a kernel event. |
e953ef25 | 770 | */ |
19e70852 | 771 | int kernel_disable_event(struct ltt_kernel_event *event) |
e953ef25 DG |
772 | { |
773 | int ret; | |
19e70852 | 774 | |
a0377dfe | 775 | LTTNG_ASSERT(event); |
0525e9ae | 776 | |
19e70852 | 777 | ret = kernctl_disable(event->fd); |
42224349 | 778 | if (ret < 0) { |
d79bd829 JG |
779 | PERROR("Failed to disable kernel event: name = '%s', fd = %d", |
780 | event->event->name, event->fd); | |
19e70852 | 781 | goto error; |
e953ef25 | 782 | } |
f3ed775e | 783 | |
19e70852 DG |
784 | event->enabled = 0; |
785 | DBG("Kernel event %s disabled (fd: %d)", event->event->name, event->fd); | |
786 | ||
f34daff7 DG |
787 | return 0; |
788 | ||
789 | error: | |
d36b8583 | 790 | return ret; |
f34daff7 | 791 | } |
aaf26714 | 792 | |
352b58f5 JR |
793 | /* |
794 | * Disable a kernel event notifier. | |
795 | */ | |
796 | static | |
797 | int kernel_disable_event_notifier_rule(struct ltt_kernel_event_notifier_rule *event) | |
798 | { | |
799 | int ret; | |
800 | ||
a0377dfe | 801 | LTTNG_ASSERT(event); |
352b58f5 JR |
802 | |
803 | rcu_read_lock(); | |
804 | cds_lfht_del(kernel_token_to_event_notifier_rule_ht, &event->ht_node); | |
805 | rcu_read_unlock(); | |
806 | ||
807 | ret = kernctl_disable(event->fd); | |
808 | if (ret < 0) { | |
d79bd829 JG |
809 | PERROR("Failed to disable kernel event notifier: fd = %d, token = %" PRIu64, |
810 | event->fd, event->token); | |
352b58f5 JR |
811 | goto error; |
812 | } | |
813 | ||
814 | event->enabled = 0; | |
815 | DBG("Disabled kernel event notifier: fd = %d, token = %" PRIu64, | |
816 | event->fd, event->token); | |
817 | ||
818 | error: | |
819 | return ret; | |
820 | } | |
821 | ||
159b042f JG |
822 | static |
823 | struct process_attr_tracker *_kernel_get_process_attr_tracker( | |
55c9e7ca | 824 | struct ltt_kernel_session *session, |
159b042f | 825 | enum lttng_process_attr process_attr) |
55c9e7ca | 826 | { |
159b042f JG |
827 | switch (process_attr) { |
828 | case LTTNG_PROCESS_ATTR_PROCESS_ID: | |
829 | return session->tracker_pid; | |
830 | case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID: | |
831 | return session->tracker_vpid; | |
832 | case LTTNG_PROCESS_ATTR_USER_ID: | |
833 | return session->tracker_uid; | |
834 | case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID: | |
835 | return session->tracker_vuid; | |
836 | case LTTNG_PROCESS_ATTR_GROUP_ID: | |
837 | return session->tracker_gid; | |
838 | case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID: | |
839 | return session->tracker_vgid; | |
55c9e7ca JR |
840 | default: |
841 | return NULL; | |
842 | } | |
843 | } | |
6e911cad | 844 | |
159b042f | 845 | const struct process_attr_tracker *kernel_get_process_attr_tracker( |
55c9e7ca | 846 | struct ltt_kernel_session *session, |
159b042f | 847 | enum lttng_process_attr process_attr) |
ccf10263 | 848 | { |
159b042f JG |
849 | return (const struct process_attr_tracker *) |
850 | _kernel_get_process_attr_tracker(session, process_attr); | |
851 | } | |
7c493d31 | 852 | |
159b042f JG |
853 | enum lttng_error_code kernel_process_attr_tracker_set_tracking_policy( |
854 | struct ltt_kernel_session *session, | |
855 | enum lttng_process_attr process_attr, | |
856 | enum lttng_tracking_policy policy) | |
857 | { | |
858 | int ret; | |
859 | enum lttng_error_code ret_code = LTTNG_OK; | |
860 | struct process_attr_tracker *tracker = | |
861 | _kernel_get_process_attr_tracker(session, process_attr); | |
862 | enum lttng_tracking_policy previous_policy; | |
55c9e7ca | 863 | |
159b042f JG |
864 | if (!tracker) { |
865 | ret_code = LTTNG_ERR_INVALID; | |
866 | goto end; | |
7c493d31 | 867 | } |
ccf10263 | 868 | |
159b042f JG |
869 | previous_policy = process_attr_tracker_get_tracking_policy(tracker); |
870 | ret = process_attr_tracker_set_tracking_policy(tracker, policy); | |
871 | if (ret) { | |
872 | ret_code = LTTNG_ERR_UNK; | |
873 | goto end; | |
55c9e7ca | 874 | } |
7c493d31 | 875 | |
159b042f | 876 | if (previous_policy == policy) { |
55c9e7ca | 877 | goto end; |
7c493d31 | 878 | } |
55c9e7ca | 879 | |
159b042f JG |
880 | switch (policy) { |
881 | case LTTNG_TRACKING_POLICY_INCLUDE_ALL: | |
882 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
883 | /* | |
884 | * Maintain a special case for the process ID process | |
885 | * attribute tracker as it was the only supported | |
886 | * attribute prior to 2.12. | |
887 | */ | |
888 | ret = kernctl_track_pid(session->fd, -1); | |
889 | } else { | |
890 | ret = kernctl_track_id(session->fd, process_attr, -1); | |
55c9e7ca JR |
891 | } |
892 | break; | |
159b042f JG |
893 | case LTTNG_TRACKING_POLICY_EXCLUDE_ALL: |
894 | case LTTNG_TRACKING_POLICY_INCLUDE_SET: | |
895 | /* fall-through. */ | |
896 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
897 | /* | |
898 | * Maintain a special case for the process ID process | |
899 | * attribute tracker as it was the only supported | |
900 | * attribute prior to 2.12. | |
901 | */ | |
902 | ret = kernctl_untrack_pid(session->fd, -1); | |
903 | } else { | |
904 | ret = kernctl_untrack_id(session->fd, process_attr, -1); | |
55c9e7ca JR |
905 | } |
906 | break; | |
907 | default: | |
159b042f | 908 | abort(); |
55c9e7ca | 909 | } |
159b042f | 910 | /* kern-ctl error handling */ |
32af2c95 | 911 | switch (-ret) { |
159b042f JG |
912 | case 0: |
913 | ret_code = LTTNG_OK; | |
914 | break; | |
7c493d31 | 915 | case EINVAL: |
159b042f | 916 | ret_code = LTTNG_ERR_INVALID; |
55c9e7ca | 917 | break; |
7c493d31 | 918 | case ENOMEM: |
159b042f | 919 | ret_code = LTTNG_ERR_NOMEM; |
55c9e7ca JR |
920 | break; |
921 | case EEXIST: | |
159b042f | 922 | ret_code = LTTNG_ERR_PROCESS_ATTR_EXISTS; |
55c9e7ca | 923 | break; |
7c493d31 | 924 | default: |
159b042f | 925 | ret_code = LTTNG_ERR_UNK; |
55c9e7ca JR |
926 | break; |
927 | } | |
55c9e7ca | 928 | end: |
159b042f | 929 | return ret_code; |
ccf10263 MD |
930 | } |
931 | ||
159b042f | 932 | enum lttng_error_code kernel_process_attr_tracker_inclusion_set_add_value( |
55c9e7ca | 933 | struct ltt_kernel_session *session, |
159b042f JG |
934 | enum lttng_process_attr process_attr, |
935 | const struct process_attr_value *value) | |
a5dfbb9d | 936 | { |
159b042f JG |
937 | int ret, integral_value; |
938 | enum lttng_error_code ret_code; | |
939 | struct process_attr_tracker *tracker; | |
940 | enum process_attr_tracker_status status; | |
a5dfbb9d | 941 | |
159b042f JG |
942 | /* |
943 | * Convert process attribute tracker value to the integral | |
944 | * representation required by the kern-ctl API. | |
945 | */ | |
946 | switch (process_attr) { | |
947 | case LTTNG_PROCESS_ATTR_PROCESS_ID: | |
948 | case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID: | |
949 | integral_value = (int) value->value.pid; | |
55c9e7ca | 950 | break; |
159b042f JG |
951 | case LTTNG_PROCESS_ATTR_USER_ID: |
952 | case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID: | |
953 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME) { | |
954 | uid_t uid; | |
955 | ||
956 | ret_code = utils_user_id_from_name( | |
957 | value->value.user_name, &uid); | |
958 | if (ret_code != LTTNG_OK) { | |
959 | goto end; | |
960 | } | |
961 | integral_value = (int) uid; | |
962 | } else { | |
963 | integral_value = (int) value->value.uid; | |
55c9e7ca JR |
964 | } |
965 | break; | |
159b042f JG |
966 | case LTTNG_PROCESS_ATTR_GROUP_ID: |
967 | case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID: | |
968 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME) { | |
969 | gid_t gid; | |
970 | ||
971 | ret_code = utils_group_id_from_name( | |
972 | value->value.group_name, &gid); | |
973 | if (ret_code != LTTNG_OK) { | |
974 | goto end; | |
975 | } | |
976 | integral_value = (int) gid; | |
977 | } else { | |
978 | integral_value = (int) value->value.gid; | |
a5dfbb9d | 979 | } |
55c9e7ca JR |
980 | break; |
981 | default: | |
159b042f JG |
982 | ret_code = LTTNG_ERR_INVALID; |
983 | goto end; | |
55c9e7ca JR |
984 | } |
985 | ||
159b042f JG |
986 | tracker = _kernel_get_process_attr_tracker(session, process_attr); |
987 | if (!tracker) { | |
988 | ret_code = LTTNG_ERR_INVALID; | |
989 | goto end; | |
990 | } | |
991 | ||
992 | status = process_attr_tracker_inclusion_set_add_value(tracker, value); | |
993 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
994 | switch (status) { | |
995 | case PROCESS_ATTR_TRACKER_STATUS_EXISTS: | |
996 | ret_code = LTTNG_ERR_PROCESS_ATTR_EXISTS; | |
997 | break; | |
998 | case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY: | |
999 | ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY; | |
1000 | break; | |
1001 | case PROCESS_ATTR_TRACKER_STATUS_ERROR: | |
1002 | default: | |
1003 | ret_code = LTTNG_ERR_UNK; | |
1004 | break; | |
1005 | } | |
1006 | goto end; | |
1007 | } | |
1008 | ||
1009 | DBG("Kernel track %s %d for session id %" PRIu64, | |
1010 | lttng_process_attr_to_string(process_attr), | |
1011 | integral_value, session->id); | |
1012 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
1013 | /* | |
1014 | * Maintain a special case for the process ID process attribute | |
1015 | * tracker as it was the only supported attribute prior to 2.12. | |
1016 | */ | |
1017 | ret = kernctl_track_pid(session->fd, integral_value); | |
1018 | } else { | |
1019 | ret = kernctl_track_id( | |
1020 | session->fd, process_attr, integral_value); | |
1021 | } | |
1022 | if (ret == 0) { | |
1023 | ret_code = LTTNG_OK; | |
1024 | goto end; | |
1025 | } | |
1026 | ||
1027 | kernel_wait_quiescent(); | |
1028 | ||
1029 | /* kern-ctl error handling */ | |
55c9e7ca | 1030 | switch (-ret) { |
159b042f JG |
1031 | case 0: |
1032 | ret_code = LTTNG_OK; | |
1033 | break; | |
55c9e7ca | 1034 | case EINVAL: |
159b042f | 1035 | ret_code = LTTNG_ERR_INVALID; |
55c9e7ca JR |
1036 | break; |
1037 | case ENOMEM: | |
159b042f | 1038 | ret_code = LTTNG_ERR_NOMEM; |
55c9e7ca JR |
1039 | break; |
1040 | case EEXIST: | |
159b042f | 1041 | ret_code = LTTNG_ERR_PROCESS_ATTR_EXISTS; |
55c9e7ca JR |
1042 | break; |
1043 | default: | |
159b042f | 1044 | ret_code = LTTNG_ERR_UNK; |
55c9e7ca | 1045 | break; |
a5dfbb9d MD |
1046 | } |
1047 | ||
159b042f JG |
1048 | /* Attempt to remove the value from the tracker. */ |
1049 | status = process_attr_tracker_inclusion_set_remove_value( | |
1050 | tracker, value); | |
1051 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
1052 | ERR("Failed to roll-back the tracking of kernel %s process attribute %d while handling a kern-ctl error", | |
1053 | lttng_process_attr_to_string(process_attr), | |
1054 | integral_value); | |
55c9e7ca | 1055 | } |
a5dfbb9d | 1056 | end: |
159b042f | 1057 | return ret_code; |
55c9e7ca | 1058 | } |
a5dfbb9d | 1059 | |
159b042f | 1060 | enum lttng_error_code kernel_process_attr_tracker_inclusion_set_remove_value( |
55c9e7ca | 1061 | struct ltt_kernel_session *session, |
159b042f JG |
1062 | enum lttng_process_attr process_attr, |
1063 | const struct process_attr_value *value) | |
55c9e7ca | 1064 | { |
159b042f JG |
1065 | int ret, integral_value; |
1066 | enum lttng_error_code ret_code; | |
1067 | struct process_attr_tracker *tracker; | |
1068 | enum process_attr_tracker_status status; | |
1069 | ||
1070 | /* | |
1071 | * Convert process attribute tracker value to the integral | |
1072 | * representation required by the kern-ctl API. | |
1073 | */ | |
1074 | switch (process_attr) { | |
1075 | case LTTNG_PROCESS_ATTR_PROCESS_ID: | |
1076 | case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID: | |
1077 | integral_value = (int) value->value.pid; | |
1078 | break; | |
1079 | case LTTNG_PROCESS_ATTR_USER_ID: | |
1080 | case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID: | |
1081 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_USER_NAME) { | |
1082 | uid_t uid; | |
1083 | ||
1084 | ret_code = utils_user_id_from_name( | |
1085 | value->value.user_name, &uid); | |
1086 | if (ret_code != LTTNG_OK) { | |
1087 | goto end; | |
1088 | } | |
1089 | integral_value = (int) uid; | |
1090 | } else { | |
1091 | integral_value = (int) value->value.uid; | |
1092 | } | |
1093 | break; | |
1094 | case LTTNG_PROCESS_ATTR_GROUP_ID: | |
1095 | case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID: | |
1096 | if (value->type == LTTNG_PROCESS_ATTR_VALUE_TYPE_GROUP_NAME) { | |
1097 | gid_t gid; | |
1098 | ||
1099 | ret_code = utils_group_id_from_name( | |
1100 | value->value.group_name, &gid); | |
1101 | if (ret_code != LTTNG_OK) { | |
1102 | goto end; | |
1103 | } | |
1104 | integral_value = (int) gid; | |
1105 | } else { | |
1106 | integral_value = (int) value->value.gid; | |
1107 | } | |
1108 | break; | |
1109 | default: | |
1110 | ret_code = LTTNG_ERR_INVALID; | |
1111 | goto end; | |
1112 | } | |
55c9e7ca | 1113 | |
159b042f JG |
1114 | tracker = _kernel_get_process_attr_tracker(session, process_attr); |
1115 | if (!tracker) { | |
1116 | ret_code = LTTNG_ERR_INVALID; | |
a7a533cd | 1117 | goto end; |
a5dfbb9d | 1118 | } |
a7a533cd | 1119 | |
159b042f JG |
1120 | status = process_attr_tracker_inclusion_set_remove_value( |
1121 | tracker, value); | |
1122 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
1123 | switch (status) { | |
1124 | case PROCESS_ATTR_TRACKER_STATUS_MISSING: | |
1125 | ret_code = LTTNG_ERR_PROCESS_ATTR_MISSING; | |
1126 | break; | |
1127 | case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY: | |
1128 | ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY; | |
1129 | break; | |
1130 | case PROCESS_ATTR_TRACKER_STATUS_ERROR: | |
1131 | default: | |
1132 | ret_code = LTTNG_ERR_UNK; | |
1133 | break; | |
1134 | } | |
a7a533cd JR |
1135 | goto end; |
1136 | } | |
1137 | ||
159b042f JG |
1138 | DBG("Kernel track %s %d for session id %" PRIu64, |
1139 | lttng_process_attr_to_string(process_attr), | |
1140 | integral_value, session->id); | |
1141 | if (process_attr == LTTNG_PROCESS_ATTR_PROCESS_ID) { | |
1142 | /* | |
1143 | * Maintain a special case for the process ID process attribute | |
1144 | * tracker as it was the only supported attribute prior to 2.12. | |
1145 | */ | |
1146 | ret = kernctl_untrack_pid(session->fd, integral_value); | |
1147 | } else { | |
1148 | ret = kernctl_untrack_id( | |
1149 | session->fd, process_attr, integral_value); | |
1150 | } | |
1151 | if (ret == 0) { | |
1152 | ret_code = LTTNG_OK; | |
1153 | goto end; | |
1154 | } | |
1155 | kernel_wait_quiescent(); | |
1156 | ||
1157 | /* kern-ctl error handling */ | |
1158 | switch (-ret) { | |
1159 | case 0: | |
1160 | ret_code = LTTNG_OK; | |
1161 | break; | |
1162 | case EINVAL: | |
1163 | ret_code = LTTNG_ERR_INVALID; | |
1164 | break; | |
1165 | case ENOMEM: | |
1166 | ret_code = LTTNG_ERR_NOMEM; | |
1167 | break; | |
1168 | case ENOENT: | |
1169 | ret_code = LTTNG_ERR_PROCESS_ATTR_MISSING; | |
1170 | break; | |
1171 | default: | |
1172 | ret_code = LTTNG_ERR_UNK; | |
1173 | break; | |
1174 | } | |
1175 | ||
1176 | /* Attempt to add the value to the tracker. */ | |
1177 | status = process_attr_tracker_inclusion_set_add_value( | |
1178 | tracker, value); | |
1179 | if (status != PROCESS_ATTR_TRACKER_STATUS_OK) { | |
1180 | ERR("Failed to roll-back the tracking of kernel %s process attribute %d while handling a kern-ctl error", | |
1181 | lttng_process_attr_to_string(process_attr), | |
1182 | integral_value); | |
1183 | } | |
a7a533cd | 1184 | end: |
159b042f | 1185 | return ret_code; |
a5dfbb9d MD |
1186 | } |
1187 | ||
aaf26714 | 1188 | /* |
050349bb DG |
1189 | * Create kernel metadata, open from the kernel tracer and add it to the |
1190 | * kernel session. | |
aaf26714 | 1191 | */ |
a4b92340 | 1192 | int kernel_open_metadata(struct ltt_kernel_session *session) |
aaf26714 DG |
1193 | { |
1194 | int ret; | |
74024a21 | 1195 | struct ltt_kernel_metadata *lkm = NULL; |
aaf26714 | 1196 | |
a0377dfe | 1197 | LTTNG_ASSERT(session); |
0525e9ae | 1198 | |
54012638 | 1199 | /* Allocate kernel metadata */ |
a4b92340 | 1200 | lkm = trace_kernel_create_metadata(); |
54012638 | 1201 | if (lkm == NULL) { |
aaf26714 DG |
1202 | goto error; |
1203 | } | |
1204 | ||
54012638 | 1205 | /* Kernel tracer metadata creation */ |
f3ed775e | 1206 | ret = kernctl_open_metadata(session->fd, &lkm->conf->attr); |
aaf26714 | 1207 | if (ret < 0) { |
74024a21 | 1208 | goto error_open; |
aaf26714 DG |
1209 | } |
1210 | ||
8c0faa1d | 1211 | lkm->fd = ret; |
d40f0359 | 1212 | lkm->key = ++next_kernel_channel_key; |
7b395890 DG |
1213 | /* Prevent fd duplication after execlp() */ |
1214 | ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC); | |
1215 | if (ret < 0) { | |
df0f840b | 1216 | PERROR("fcntl session fd"); |
7b395890 DG |
1217 | } |
1218 | ||
aaf26714 | 1219 | session->metadata = lkm; |
8c0faa1d | 1220 | |
00e2e675 | 1221 | DBG("Kernel metadata opened (fd: %d)", lkm->fd); |
8c0faa1d DG |
1222 | |
1223 | return 0; | |
1224 | ||
74024a21 DG |
1225 | error_open: |
1226 | trace_kernel_destroy_metadata(lkm); | |
8c0faa1d | 1227 | error: |
54012638 | 1228 | return -1; |
8c0faa1d DG |
1229 | } |
1230 | ||
1231 | /* | |
050349bb | 1232 | * Start tracing session. |
8c0faa1d DG |
1233 | */ |
1234 | int kernel_start_session(struct ltt_kernel_session *session) | |
1235 | { | |
1236 | int ret; | |
1237 | ||
a0377dfe | 1238 | LTTNG_ASSERT(session); |
0525e9ae | 1239 | |
8c0faa1d DG |
1240 | ret = kernctl_start_session(session->fd); |
1241 | if (ret < 0) { | |
df0f840b | 1242 | PERROR("ioctl start session"); |
8c0faa1d DG |
1243 | goto error; |
1244 | } | |
1245 | ||
1246 | DBG("Kernel session started"); | |
1247 | ||
1248 | return 0; | |
1249 | ||
1250 | error: | |
1251 | return ret; | |
1252 | } | |
1253 | ||
f3ed775e | 1254 | /* |
050349bb | 1255 | * Make a kernel wait to make sure in-flight probe have completed. |
f3ed775e | 1256 | */ |
7d268848 | 1257 | void kernel_wait_quiescent(void) |
f3ed775e DG |
1258 | { |
1259 | int ret; | |
7d268848 | 1260 | int fd = kernel_tracer_fd; |
f3ed775e DG |
1261 | |
1262 | DBG("Kernel quiescent wait on %d", fd); | |
1263 | ||
1264 | ret = kernctl_wait_quiescent(fd); | |
1265 | if (ret < 0) { | |
df0f840b | 1266 | PERROR("wait quiescent ioctl"); |
f3ed775e DG |
1267 | ERR("Kernel quiescent wait failed"); |
1268 | } | |
1269 | } | |
1270 | ||
1271 | /* | |
f3ed775e DG |
1272 | * Force flush buffer of metadata. |
1273 | */ | |
1274 | int kernel_metadata_flush_buffer(int fd) | |
1275 | { | |
1276 | int ret; | |
1277 | ||
169d2cb7 DG |
1278 | DBG("Kernel flushing metadata buffer on fd %d", fd); |
1279 | ||
f3ed775e DG |
1280 | ret = kernctl_buffer_flush(fd); |
1281 | if (ret < 0) { | |
00e2e675 | 1282 | ERR("Fail to flush metadata buffers %d (ret: %d)", fd, ret); |
f3ed775e DG |
1283 | } |
1284 | ||
1285 | return 0; | |
1286 | } | |
1287 | ||
1288 | /* | |
050349bb | 1289 | * Force flush buffer for channel. |
f3ed775e DG |
1290 | */ |
1291 | int kernel_flush_buffer(struct ltt_kernel_channel *channel) | |
1292 | { | |
1293 | int ret; | |
1294 | struct ltt_kernel_stream *stream; | |
1295 | ||
a0377dfe | 1296 | LTTNG_ASSERT(channel); |
0525e9ae | 1297 | |
f3ed775e DG |
1298 | DBG("Flush buffer for channel %s", channel->channel->name); |
1299 | ||
1300 | cds_list_for_each_entry(stream, &channel->stream_list.head, list) { | |
1301 | DBG("Flushing channel stream %d", stream->fd); | |
1302 | ret = kernctl_buffer_flush(stream->fd); | |
1303 | if (ret < 0) { | |
df0f840b | 1304 | PERROR("ioctl"); |
f3ed775e DG |
1305 | ERR("Fail to flush buffer for stream %d (ret: %d)", |
1306 | stream->fd, ret); | |
1307 | } | |
1308 | } | |
1309 | ||
1310 | return 0; | |
1311 | } | |
1312 | ||
8c0faa1d | 1313 | /* |
050349bb | 1314 | * Stop tracing session. |
8c0faa1d DG |
1315 | */ |
1316 | int kernel_stop_session(struct ltt_kernel_session *session) | |
1317 | { | |
1318 | int ret; | |
1319 | ||
a0377dfe | 1320 | LTTNG_ASSERT(session); |
0525e9ae | 1321 | |
8c0faa1d DG |
1322 | ret = kernctl_stop_session(session->fd); |
1323 | if (ret < 0) { | |
1324 | goto error; | |
1325 | } | |
1326 | ||
1327 | DBG("Kernel session stopped"); | |
1328 | ||
1329 | return 0; | |
1330 | ||
1331 | error: | |
1332 | return ret; | |
1333 | } | |
1334 | ||
1335 | /* | |
050349bb DG |
1336 | * Open stream of channel, register it to the kernel tracer and add it |
1337 | * to the stream list of the channel. | |
8c0faa1d | 1338 | * |
1cfb4b98 MD |
1339 | * Note: given that the streams may appear in random order wrt CPU |
1340 | * number (e.g. cpu hotplug), the index value of the stream number in | |
1341 | * the stream name is not necessarily linked to the CPU number. | |
1342 | * | |
050349bb | 1343 | * Return the number of created stream. Else, a negative value. |
8c0faa1d | 1344 | */ |
f3ed775e | 1345 | int kernel_open_channel_stream(struct ltt_kernel_channel *channel) |
8c0faa1d | 1346 | { |
1cfb4b98 | 1347 | int ret; |
8c0faa1d DG |
1348 | struct ltt_kernel_stream *lks; |
1349 | ||
a0377dfe | 1350 | LTTNG_ASSERT(channel); |
0525e9ae | 1351 | |
5a47c6a2 | 1352 | while ((ret = kernctl_create_stream(channel->fd)) >= 0) { |
1cfb4b98 MD |
1353 | lks = trace_kernel_create_stream(channel->channel->name, |
1354 | channel->stream_count); | |
8c0faa1d | 1355 | if (lks == NULL) { |
799e2c4f MD |
1356 | ret = close(ret); |
1357 | if (ret) { | |
1358 | PERROR("close"); | |
1359 | } | |
8c0faa1d DG |
1360 | goto error; |
1361 | } | |
1362 | ||
1363 | lks->fd = ret; | |
7b395890 DG |
1364 | /* Prevent fd duplication after execlp() */ |
1365 | ret = fcntl(lks->fd, F_SETFD, FD_CLOEXEC); | |
1366 | if (ret < 0) { | |
df0f840b | 1367 | PERROR("fcntl session fd"); |
7b395890 DG |
1368 | } |
1369 | ||
1624d5b7 JD |
1370 | lks->tracefile_size = channel->channel->attr.tracefile_size; |
1371 | lks->tracefile_count = channel->channel->attr.tracefile_count; | |
1372 | ||
1cfb4b98 | 1373 | /* Add stream to channel stream list */ |
8c0faa1d DG |
1374 | cds_list_add(&lks->list, &channel->stream_list.head); |
1375 | channel->stream_count++; | |
8c0faa1d | 1376 | |
00e2e675 DG |
1377 | DBG("Kernel stream %s created (fd: %d, state: %d)", lks->name, lks->fd, |
1378 | lks->state); | |
54012638 | 1379 | } |
8c0faa1d DG |
1380 | |
1381 | return channel->stream_count; | |
1382 | ||
1383 | error: | |
54012638 | 1384 | return -1; |
8c0faa1d DG |
1385 | } |
1386 | ||
1387 | /* | |
050349bb | 1388 | * Open the metadata stream and set it to the kernel session. |
8c0faa1d | 1389 | */ |
f3ed775e | 1390 | int kernel_open_metadata_stream(struct ltt_kernel_session *session) |
8c0faa1d DG |
1391 | { |
1392 | int ret; | |
1393 | ||
a0377dfe | 1394 | LTTNG_ASSERT(session); |
0525e9ae | 1395 | |
8c0faa1d DG |
1396 | ret = kernctl_create_stream(session->metadata->fd); |
1397 | if (ret < 0) { | |
df0f840b | 1398 | PERROR("kernel create metadata stream"); |
8c0faa1d DG |
1399 | goto error; |
1400 | } | |
1401 | ||
1402 | DBG("Kernel metadata stream created (fd: %d)", ret); | |
1403 | session->metadata_stream_fd = ret; | |
7b395890 DG |
1404 | /* Prevent fd duplication after execlp() */ |
1405 | ret = fcntl(session->metadata_stream_fd, F_SETFD, FD_CLOEXEC); | |
1406 | if (ret < 0) { | |
df0f840b | 1407 | PERROR("fcntl session fd"); |
7b395890 | 1408 | } |
aaf26714 DG |
1409 | |
1410 | return 0; | |
1411 | ||
1412 | error: | |
54012638 | 1413 | return -1; |
aaf26714 | 1414 | } |
2ef84c95 DG |
1415 | |
1416 | /* | |
9f19cc17 | 1417 | * Get the event list from the kernel tracer and return the number of elements. |
2ef84c95 | 1418 | */ |
7d268848 | 1419 | ssize_t kernel_list_events(struct lttng_event **events) |
2ef84c95 | 1420 | { |
53efb85a | 1421 | int fd, ret; |
9f19cc17 DG |
1422 | char *event; |
1423 | size_t nbmem, count = 0; | |
2ef84c95 | 1424 | FILE *fp; |
9f19cc17 | 1425 | struct lttng_event *elist; |
2ef84c95 | 1426 | |
a0377dfe | 1427 | LTTNG_ASSERT(events); |
0525e9ae | 1428 | |
7d268848 | 1429 | fd = kernctl_tracepoint_list(kernel_tracer_fd); |
2ef84c95 | 1430 | if (fd < 0) { |
df0f840b | 1431 | PERROR("kernel tracepoint list"); |
2ef84c95 DG |
1432 | goto error; |
1433 | } | |
1434 | ||
1435 | fp = fdopen(fd, "r"); | |
1436 | if (fp == NULL) { | |
df0f840b | 1437 | PERROR("kernel tracepoint list fdopen"); |
61b73b12 | 1438 | goto error_fp; |
2ef84c95 DG |
1439 | } |
1440 | ||
1441 | /* | |
1442 | * Init memory size counter | |
1443 | * See kernel-ctl.h for explanation of this value | |
1444 | */ | |
6725fe19 | 1445 | nbmem = KERNEL_EVENT_INIT_LIST_SIZE; |
64803277 | 1446 | elist = calloc<lttng_event>(nbmem); |
3b870559 MD |
1447 | if (elist == NULL) { |
1448 | PERROR("alloc list events"); | |
1449 | count = -ENOMEM; | |
1450 | goto end; | |
1451 | } | |
2ef84c95 | 1452 | |
53efb85a | 1453 | while (fscanf(fp, "event { name = %m[^;]; };\n", &event) == 1) { |
6725fe19 | 1454 | if (count >= nbmem) { |
3b870559 | 1455 | struct lttng_event *new_elist; |
53efb85a | 1456 | size_t new_nbmem; |
3b870559 | 1457 | |
53efb85a MD |
1458 | new_nbmem = nbmem << 1; |
1459 | DBG("Reallocating event list from %zu to %zu bytes", | |
1460 | nbmem, new_nbmem); | |
7966af57 | 1461 | new_elist = (lttng_event *) realloc(elist, new_nbmem * sizeof(struct lttng_event)); |
3b870559 | 1462 | if (new_elist == NULL) { |
df0f840b | 1463 | PERROR("realloc list events"); |
3b870559 MD |
1464 | free(event); |
1465 | free(elist); | |
61b73b12 MD |
1466 | count = -ENOMEM; |
1467 | goto end; | |
2ef84c95 | 1468 | } |
53efb85a MD |
1469 | /* Zero the new memory */ |
1470 | memset(new_elist + nbmem, 0, | |
1471 | (new_nbmem - nbmem) * sizeof(struct lttng_event)); | |
1472 | nbmem = new_nbmem; | |
3b870559 | 1473 | elist = new_elist; |
2ef84c95 | 1474 | } |
99497cd0 MD |
1475 | strncpy(elist[count].name, event, LTTNG_SYMBOL_NAME_LEN); |
1476 | elist[count].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; | |
67b9d018 | 1477 | elist[count].enabled = -1; |
9f19cc17 | 1478 | count++; |
3b870559 | 1479 | free(event); |
2ef84c95 DG |
1480 | } |
1481 | ||
9f19cc17 | 1482 | *events = elist; |
ced2f820 | 1483 | DBG("Kernel list events done (%zu events)", count); |
61b73b12 | 1484 | end: |
799e2c4f MD |
1485 | ret = fclose(fp); /* closes both fp and fd */ |
1486 | if (ret) { | |
1487 | PERROR("fclose"); | |
1488 | } | |
9f19cc17 | 1489 | return count; |
2ef84c95 | 1490 | |
61b73b12 | 1491 | error_fp: |
799e2c4f MD |
1492 | ret = close(fd); |
1493 | if (ret) { | |
1494 | PERROR("close"); | |
1495 | } | |
2ef84c95 DG |
1496 | error: |
1497 | return -1; | |
1498 | } | |
096102bd DG |
1499 | |
1500 | /* | |
1501 | * Get kernel version and validate it. | |
1502 | */ | |
b8e2fb80 FD |
1503 | int kernel_validate_version(struct lttng_kernel_abi_tracer_version *version, |
1504 | struct lttng_kernel_abi_tracer_abi_version *abi_version) | |
096102bd DG |
1505 | { |
1506 | int ret; | |
096102bd | 1507 | |
7d268848 | 1508 | ret = kernctl_tracer_version(kernel_tracer_fd, version); |
096102bd | 1509 | if (ret < 0) { |
521dd134 | 1510 | ERR("Failed to retrieve the lttng-modules version"); |
096102bd DG |
1511 | goto error; |
1512 | } | |
1513 | ||
1514 | /* Validate version */ | |
88076e89 | 1515 | if (version->major != VERSION_MAJOR) { |
c052142c | 1516 | ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)", |
88076e89 | 1517 | version->major, VERSION_MAJOR); |
096102bd | 1518 | goto error_version; |
096102bd | 1519 | } |
7d268848 | 1520 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, abi_version); |
c052142c | 1521 | if (ret < 0) { |
521dd134 | 1522 | ERR("Failed to retrieve lttng-modules ABI version"); |
c052142c MD |
1523 | goto error; |
1524 | } | |
b8e2fb80 | 1525 | if (abi_version->major != LTTNG_KERNEL_ABI_MAJOR_VERSION) { |
521dd134 | 1526 | ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)", |
88076e89 | 1527 | abi_version->major, abi_version->minor, |
b8e2fb80 | 1528 | LTTNG_KERNEL_ABI_MAJOR_VERSION); |
c052142c MD |
1529 | goto error; |
1530 | } | |
1531 | DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)", | |
88076e89 JD |
1532 | version->major, version->minor, |
1533 | abi_version->major, abi_version->minor); | |
096102bd DG |
1534 | return 0; |
1535 | ||
1536 | error_version: | |
096102bd DG |
1537 | ret = -1; |
1538 | ||
1539 | error: | |
521dd134 | 1540 | ERR("Kernel tracer version check failed; kernel tracing will not be available"); |
096102bd DG |
1541 | return ret; |
1542 | } | |
335a95b7 MD |
1543 | |
1544 | /* | |
1545 | * Kernel work-arounds called at the start of sessiond main(). | |
1546 | */ | |
1547 | int init_kernel_workarounds(void) | |
1548 | { | |
8936c33a | 1549 | int ret; |
335a95b7 MD |
1550 | FILE *fp; |
1551 | ||
1552 | /* | |
1553 | * boot_id needs to be read once before being used concurrently | |
1554 | * to deal with a Linux kernel race. A fix is proposed for | |
1555 | * upstream, but the work-around is needed for older kernels. | |
1556 | */ | |
1557 | fp = fopen("/proc/sys/kernel/random/boot_id", "r"); | |
1558 | if (!fp) { | |
1559 | goto end_boot_id; | |
1560 | } | |
1561 | while (!feof(fp)) { | |
1562 | char buf[37] = ""; | |
1563 | ||
8936c33a DG |
1564 | ret = fread(buf, 1, sizeof(buf), fp); |
1565 | if (ret < 0) { | |
1566 | /* Ignore error, we don't really care */ | |
1567 | } | |
335a95b7 | 1568 | } |
799e2c4f MD |
1569 | ret = fclose(fp); |
1570 | if (ret) { | |
1571 | PERROR("fclose"); | |
1572 | } | |
335a95b7 | 1573 | end_boot_id: |
335a95b7 MD |
1574 | return 0; |
1575 | } | |
2f77fc4b DG |
1576 | |
1577 | /* | |
d070c424 | 1578 | * Teardown of a kernel session, keeping data required by destroy notifiers. |
2f77fc4b DG |
1579 | */ |
1580 | void kernel_destroy_session(struct ltt_kernel_session *ksess) | |
1581 | { | |
82b69413 JG |
1582 | struct lttng_trace_chunk *trace_chunk; |
1583 | ||
2f77fc4b DG |
1584 | if (ksess == NULL) { |
1585 | DBG3("No kernel session when tearing down session"); | |
1586 | return; | |
1587 | } | |
1588 | ||
1589 | DBG("Tearing down kernel session"); | |
82b69413 | 1590 | trace_chunk = ksess->current_trace_chunk; |
2f77fc4b | 1591 | |
07b86b52 | 1592 | /* |
15dc512a DG |
1593 | * Destroy channels on the consumer if at least one FD has been sent and we |
1594 | * are in no output mode because the streams are in *no* monitor mode so we | |
1595 | * have to send a command to clean them up or else they leaked. | |
07b86b52 | 1596 | */ |
15dc512a | 1597 | if (!ksess->output_traces && ksess->consumer_fds_sent) { |
07b86b52 JD |
1598 | int ret; |
1599 | struct consumer_socket *socket; | |
1600 | struct lttng_ht_iter iter; | |
1601 | ||
1602 | /* For each consumer socket. */ | |
d069d577 | 1603 | rcu_read_lock(); |
07b86b52 JD |
1604 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, |
1605 | socket, node.node) { | |
1606 | struct ltt_kernel_channel *chan; | |
1607 | ||
1608 | /* For each channel, ask the consumer to destroy it. */ | |
1609 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
1610 | ret = kernel_consumer_destroy_channel(socket, chan); | |
1611 | if (ret < 0) { | |
1612 | /* Consumer is probably dead. Use next socket. */ | |
1613 | continue; | |
1614 | } | |
1615 | } | |
1616 | } | |
d069d577 | 1617 | rcu_read_unlock(); |
07b86b52 JD |
1618 | } |
1619 | ||
2f77fc4b DG |
1620 | /* Close any relayd session */ |
1621 | consumer_output_send_destroy_relayd(ksess->consumer); | |
1622 | ||
1623 | trace_kernel_destroy_session(ksess); | |
82b69413 | 1624 | lttng_trace_chunk_put(trace_chunk); |
2f77fc4b | 1625 | } |
fb5f35b6 | 1626 | |
d070c424 MD |
1627 | /* Teardown of data required by destroy notifiers. */ |
1628 | void kernel_free_session(struct ltt_kernel_session *ksess) | |
1629 | { | |
1630 | if (ksess == NULL) { | |
1631 | return; | |
1632 | } | |
1633 | trace_kernel_free_session(ksess); | |
1634 | } | |
1635 | ||
fb5f35b6 DG |
1636 | /* |
1637 | * Destroy a kernel channel object. It does not do anything on the tracer side. | |
1638 | */ | |
1639 | void kernel_destroy_channel(struct ltt_kernel_channel *kchan) | |
1640 | { | |
1641 | struct ltt_kernel_session *ksess = NULL; | |
1642 | ||
a0377dfe FD |
1643 | LTTNG_ASSERT(kchan); |
1644 | LTTNG_ASSERT(kchan->channel); | |
fb5f35b6 DG |
1645 | |
1646 | DBG3("Kernel destroy channel %s", kchan->channel->name); | |
1647 | ||
1648 | /* Update channel count of associated session. */ | |
1649 | if (kchan->session) { | |
1650 | /* Keep pointer reference so we can update it after the destroy. */ | |
1651 | ksess = kchan->session; | |
1652 | } | |
1653 | ||
1654 | trace_kernel_destroy_channel(kchan); | |
1655 | ||
1656 | /* | |
1657 | * At this point the kernel channel is not visible anymore. This is safe | |
1658 | * since in order to work on a visible kernel session, the tracing session | |
1659 | * lock (ltt_session.lock) MUST be acquired. | |
1660 | */ | |
1661 | if (ksess) { | |
1662 | ksess->channel_count--; | |
1663 | } | |
1664 | } | |
6dc3064a DG |
1665 | |
1666 | /* | |
1667 | * Take a snapshot for a given kernel session. | |
1668 | * | |
9a654598 | 1669 | * Return LTTNG_OK on success or else return a LTTNG_ERR code. |
6dc3064a | 1670 | */ |
fb9a95c4 JG |
1671 | enum lttng_error_code kernel_snapshot_record( |
1672 | struct ltt_kernel_session *ksess, | |
f46376a1 | 1673 | const struct consumer_output *output, |
d07ceecd | 1674 | uint64_t nb_packets_per_stream) |
6dc3064a | 1675 | { |
2a06df8d | 1676 | int err, ret, saved_metadata_fd; |
9a654598 | 1677 | enum lttng_error_code status = LTTNG_OK; |
6dc3064a DG |
1678 | struct consumer_socket *socket; |
1679 | struct lttng_ht_iter iter; | |
1680 | struct ltt_kernel_metadata *saved_metadata; | |
3b967712 | 1681 | char *trace_path = NULL; |
5da88b0f | 1682 | size_t consumer_path_offset = 0; |
6dc3064a | 1683 | |
a0377dfe FD |
1684 | LTTNG_ASSERT(ksess); |
1685 | LTTNG_ASSERT(ksess->consumer); | |
1686 | LTTNG_ASSERT(output); | |
6dc3064a DG |
1687 | |
1688 | DBG("Kernel snapshot record started"); | |
1689 | ||
1690 | /* Save current metadata since the following calls will change it. */ | |
1691 | saved_metadata = ksess->metadata; | |
1692 | saved_metadata_fd = ksess->metadata_stream_fd; | |
1693 | ||
1694 | rcu_read_lock(); | |
1695 | ||
1696 | ret = kernel_open_metadata(ksess); | |
1697 | if (ret < 0) { | |
9a654598 | 1698 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1699 | goto error; |
1700 | } | |
1701 | ||
1702 | ret = kernel_open_metadata_stream(ksess); | |
1703 | if (ret < 0) { | |
9a654598 | 1704 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1705 | goto error_open_stream; |
1706 | } | |
1707 | ||
3b967712 | 1708 | trace_path = setup_channel_trace_path(ksess->consumer, |
bd666153 | 1709 | "", &consumer_path_offset); |
3b967712 MD |
1710 | if (!trace_path) { |
1711 | status = LTTNG_ERR_INVALID; | |
1712 | goto error; | |
1713 | } | |
6dc3064a | 1714 | /* Send metadata to consumer and snapshot everything. */ |
348a81dc | 1715 | cds_lfht_for_each_entry(output->socks->ht, &iter.iter, |
6dc3064a | 1716 | socket, node.node) { |
6dc3064a | 1717 | struct ltt_kernel_channel *chan; |
6dc3064a | 1718 | |
6dc3064a DG |
1719 | pthread_mutex_lock(socket->lock); |
1720 | /* This stream must not be monitored by the consumer. */ | |
07b86b52 | 1721 | ret = kernel_consumer_add_metadata(socket, ksess, 0); |
6dc3064a | 1722 | pthread_mutex_unlock(socket->lock); |
6dc3064a | 1723 | if (ret < 0) { |
0ed78e50 | 1724 | status = LTTNG_ERR_KERN_META_FAIL; |
6dc3064a DG |
1725 | goto error_consumer; |
1726 | } | |
1727 | ||
1728 | /* For each channel, ask the consumer to snapshot it. */ | |
1729 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
9a654598 | 1730 | status = consumer_snapshot_channel(socket, chan->key, output, 0, |
f46376a1 | 1731 | &trace_path[consumer_path_offset], |
d2956687 | 1732 | nb_packets_per_stream); |
9a654598 | 1733 | if (status != LTTNG_OK) { |
2a06df8d DG |
1734 | (void) kernel_consumer_destroy_metadata(socket, |
1735 | ksess->metadata); | |
6dc3064a DG |
1736 | goto error_consumer; |
1737 | } | |
1738 | } | |
1739 | ||
1740 | /* Snapshot metadata, */ | |
9a654598 | 1741 | status = consumer_snapshot_channel(socket, ksess->metadata->key, output, |
f46376a1 | 1742 | 1, &trace_path[consumer_path_offset], 0); |
9a654598 | 1743 | if (status != LTTNG_OK) { |
6dc3064a DG |
1744 | goto error_consumer; |
1745 | } | |
07b86b52 JD |
1746 | |
1747 | /* | |
1748 | * The metadata snapshot is done, ask the consumer to destroy it since | |
1749 | * it's not monitored on the consumer side. | |
1750 | */ | |
1751 | (void) kernel_consumer_destroy_metadata(socket, ksess->metadata); | |
6dc3064a DG |
1752 | } |
1753 | ||
1754 | error_consumer: | |
1755 | /* Close newly opened metadata stream. It's now on the consumer side. */ | |
2a06df8d DG |
1756 | err = close(ksess->metadata_stream_fd); |
1757 | if (err < 0) { | |
6dc3064a DG |
1758 | PERROR("close snapshot kernel"); |
1759 | } | |
1760 | ||
1761 | error_open_stream: | |
1762 | trace_kernel_destroy_metadata(ksess->metadata); | |
1763 | error: | |
1764 | /* Restore metadata state.*/ | |
1765 | ksess->metadata = saved_metadata; | |
1766 | ksess->metadata_stream_fd = saved_metadata_fd; | |
6dc3064a | 1767 | rcu_read_unlock(); |
3b967712 | 1768 | free(trace_path); |
9a654598 | 1769 | return status; |
6dc3064a | 1770 | } |
834978fd DG |
1771 | |
1772 | /* | |
1773 | * Get the syscall mask array from the kernel tracer. | |
1774 | * | |
1775 | * Return 0 on success else a negative value. In both case, syscall_mask should | |
1776 | * be freed. | |
1777 | */ | |
1778 | int kernel_syscall_mask(int chan_fd, char **syscall_mask, uint32_t *nr_bits) | |
1779 | { | |
a0377dfe FD |
1780 | LTTNG_ASSERT(syscall_mask); |
1781 | LTTNG_ASSERT(nr_bits); | |
834978fd DG |
1782 | |
1783 | return kernctl_syscall_mask(chan_fd, syscall_mask, nr_bits); | |
1784 | } | |
6e21424e | 1785 | |
959e3c66 JR |
1786 | static |
1787 | int kernel_tracer_abi_greater_or_equal(unsigned int major, unsigned int minor) | |
6e21424e | 1788 | { |
959e3c66 | 1789 | int ret; |
b8e2fb80 | 1790 | struct lttng_kernel_abi_tracer_abi_version abi; |
6e21424e | 1791 | |
7d268848 | 1792 | ret = kernctl_tracer_abi_version(kernel_tracer_fd, &abi); |
6e21424e JR |
1793 | if (ret < 0) { |
1794 | ERR("Failed to retrieve lttng-modules ABI version"); | |
1795 | goto error; | |
1796 | } | |
1797 | ||
959e3c66 JR |
1798 | ret = abi.major > major || (abi.major == major && abi.minor >= minor); |
1799 | error: | |
1800 | return ret; | |
1801 | } | |
1802 | ||
1803 | /* | |
1804 | * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi | |
1805 | * version number. | |
1806 | * | |
1807 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1808 | * of errors. | |
1809 | */ | |
1810 | int kernel_supports_ring_buffer_snapshot_sample_positions(void) | |
1811 | { | |
6e21424e JR |
1812 | /* |
1813 | * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3 | |
1814 | */ | |
959e3c66 | 1815 | return kernel_tracer_abi_greater_or_equal(2, 3); |
6e21424e | 1816 | } |
5c408ad8 | 1817 | |
a40a503f MD |
1818 | /* |
1819 | * Check for the support of the packet sequence number via abi version number. | |
1820 | * | |
1821 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1822 | * of errors. | |
1823 | */ | |
1824 | int kernel_supports_ring_buffer_packet_sequence_number(void) | |
1825 | { | |
a40a503f | 1826 | /* |
3029bc92 JG |
1827 | * Packet sequence number was introduced in LTTng 2.8, |
1828 | * lttng-modules ABI 2.1. | |
a40a503f | 1829 | */ |
959e3c66 JR |
1830 | return kernel_tracer_abi_greater_or_equal(2, 1); |
1831 | } | |
1832 | ||
1833 | /* | |
1834 | * Check for the support of event notifiers via abi version number. | |
1835 | * | |
1836 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1837 | * of errors. | |
1838 | */ | |
1839 | int kernel_supports_event_notifiers(void) | |
1840 | { | |
1841 | /* | |
1842 | * Event notifiers were introduced in LTTng 2.13, lttng-modules ABI 2.6. | |
1843 | */ | |
1844 | return kernel_tracer_abi_greater_or_equal(2, 6); | |
a40a503f MD |
1845 | } |
1846 | ||
346732ae JR |
1847 | /* |
1848 | * Check for the support of ctf2 via abi version number. | |
1849 | * | |
1850 | * Return 1 on success, 0 when feature is not supported, negative value in case | |
1851 | * of errors. | |
1852 | */ | |
1853 | int kernel_supports_ctf2(void) | |
1854 | { | |
1855 | /* | |
1856 | * JORAJ TODO: change this for the actual value when merged upstream | |
1857 | * default to 2.7 ABI for now (modules 2.14) | |
1858 | * CTF2 support was introduced in LTTng 2.1XX, lttng-modules ABI 2.XX. | |
1859 | */ | |
1860 | return kernel_tracer_abi_greater_or_equal(2, 7); | |
1861 | } | |
1862 | ||
5c408ad8 JD |
1863 | /* |
1864 | * Rotate a kernel session. | |
1865 | * | |
d5a1b7aa | 1866 | * Return LTTNG_OK on success or else an LTTng error code. |
5c408ad8 | 1867 | */ |
d5a1b7aa | 1868 | enum lttng_error_code kernel_rotate_session(struct ltt_session *session) |
5c408ad8 JD |
1869 | { |
1870 | int ret; | |
d5a1b7aa | 1871 | enum lttng_error_code status = LTTNG_OK; |
5c408ad8 JD |
1872 | struct consumer_socket *socket; |
1873 | struct lttng_ht_iter iter; | |
1874 | struct ltt_kernel_session *ksess = session->kernel_session; | |
1875 | ||
a0377dfe FD |
1876 | LTTNG_ASSERT(ksess); |
1877 | LTTNG_ASSERT(ksess->consumer); | |
5c408ad8 JD |
1878 | |
1879 | DBG("Rotate kernel session %s started (session %" PRIu64 ")", | |
1880 | session->name, session->id); | |
1881 | ||
1882 | rcu_read_lock(); | |
1883 | ||
1884 | /* | |
1885 | * Note that this loop will end after one iteration given that there is | |
1886 | * only one kernel consumer. | |
1887 | */ | |
1888 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
1889 | socket, node.node) { | |
1890 | struct ltt_kernel_channel *chan; | |
1891 | ||
b8a1b0bd | 1892 | /* For each channel, ask the consumer to rotate it. */ |
5c408ad8 | 1893 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { |
92816cc3 JG |
1894 | DBG("Rotate kernel channel %" PRIu64 ", session %s", |
1895 | chan->key, session->name); | |
5c408ad8 | 1896 | ret = consumer_rotate_channel(socket, chan->key, |
f46376a1 | 1897 | ksess->consumer, |
d2956687 | 1898 | /* is_metadata_channel */ false); |
5c408ad8 | 1899 | if (ret < 0) { |
7e0de219 | 1900 | status = LTTNG_ERR_ROTATION_FAIL_CONSUMER; |
5c408ad8 JD |
1901 | goto error; |
1902 | } | |
1903 | } | |
1904 | ||
1905 | /* | |
1906 | * Rotate the metadata channel. | |
1907 | */ | |
22a1b931 | 1908 | ret = consumer_rotate_channel(socket, ksess->metadata->key, |
f46376a1 | 1909 | ksess->consumer, |
d2956687 | 1910 | /* is_metadata_channel */ true); |
5c408ad8 | 1911 | if (ret < 0) { |
7e0de219 | 1912 | status = LTTNG_ERR_ROTATION_FAIL_CONSUMER; |
5c408ad8 JD |
1913 | goto error; |
1914 | } | |
1915 | } | |
1916 | ||
5c408ad8 JD |
1917 | error: |
1918 | rcu_read_unlock(); | |
d5a1b7aa | 1919 | return status; |
5c408ad8 | 1920 | } |
d2956687 JG |
1921 | |
1922 | enum lttng_error_code kernel_create_channel_subdirectories( | |
1923 | const struct ltt_kernel_session *ksess) | |
1924 | { | |
1925 | enum lttng_error_code ret = LTTNG_OK; | |
1926 | enum lttng_trace_chunk_status chunk_status; | |
1927 | ||
1928 | rcu_read_lock(); | |
a0377dfe | 1929 | LTTNG_ASSERT(ksess->current_trace_chunk); |
d2956687 JG |
1930 | |
1931 | /* | |
1932 | * Create the index subdirectory which will take care | |
1933 | * of implicitly creating the channel's path. | |
1934 | */ | |
1935 | chunk_status = lttng_trace_chunk_create_subdirectory( | |
1936 | ksess->current_trace_chunk, | |
1937 | DEFAULT_KERNEL_TRACE_DIR "/" DEFAULT_INDEX_DIR); | |
1938 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { | |
1939 | ret = LTTNG_ERR_CREATE_DIR_FAIL; | |
1940 | goto error; | |
1941 | } | |
1942 | error: | |
1943 | rcu_read_unlock(); | |
1944 | return ret; | |
1945 | } | |
7d268848 MD |
1946 | |
1947 | /* | |
1948 | * Setup necessary data for kernel tracer action. | |
1949 | */ | |
7d268848 MD |
1950 | int init_kernel_tracer(void) |
1951 | { | |
1952 | int ret; | |
1953 | bool is_root = !getuid(); | |
1954 | ||
1955 | /* Modprobe lttng kernel modules */ | |
1956 | ret = modprobe_lttng_control(); | |
1957 | if (ret < 0) { | |
1958 | goto error; | |
1959 | } | |
1960 | ||
1961 | /* Open debugfs lttng */ | |
1962 | kernel_tracer_fd = open(module_proc_lttng, O_RDWR); | |
1963 | if (kernel_tracer_fd < 0) { | |
1964 | DBG("Failed to open %s", module_proc_lttng); | |
1965 | goto error_open; | |
1966 | } | |
1967 | ||
1968 | /* Validate kernel version */ | |
412d7227 SM |
1969 | ret = kernel_validate_version(&the_kernel_tracer_version, |
1970 | &the_kernel_tracer_abi_version); | |
7d268848 MD |
1971 | if (ret < 0) { |
1972 | goto error_version; | |
1973 | } | |
1974 | ||
1975 | ret = modprobe_lttng_data(); | |
1976 | if (ret < 0) { | |
1977 | goto error_modules; | |
1978 | } | |
1979 | ||
1980 | ret = kernel_supports_ring_buffer_snapshot_sample_positions(); | |
1981 | if (ret < 0) { | |
1982 | goto error_modules; | |
1983 | } | |
7d268848 MD |
1984 | if (ret < 1) { |
1985 | WARN("Kernel tracer does not support buffer monitoring. " | |
1986 | "The monitoring timer of channels in the kernel domain " | |
1987 | "will be set to 0 (disabled)."); | |
1988 | } | |
1989 | ||
352b58f5 JR |
1990 | ret = kernel_supports_event_notifiers(); |
1991 | if (ret < 0) { | |
1992 | ERR("Failed to check for kernel tracer event notifier support"); | |
1993 | goto error_modules; | |
1994 | } | |
1995 | ret = kernel_create_event_notifier_group(&kernel_tracer_event_notifier_group_fd); | |
1996 | if (ret < 0) { | |
1997 | /* This is not fatal. */ | |
1998 | WARN("Failed to create kernel event notifier group"); | |
1999 | kernel_tracer_event_notifier_group_fd = -1; | |
2000 | } else { | |
90aa04a1 FD |
2001 | enum event_notifier_error_accounting_status error_accounting_status; |
2002 | enum lttng_error_code error_code_ret = | |
352b58f5 JR |
2003 | kernel_create_event_notifier_group_notification_fd( |
2004 | &kernel_tracer_event_notifier_group_notification_fd); | |
2005 | ||
2006 | if (error_code_ret != LTTNG_OK) { | |
2007 | goto error_modules; | |
2008 | } | |
2009 | ||
90aa04a1 FD |
2010 | error_accounting_status = event_notifier_error_accounting_register_kernel( |
2011 | kernel_tracer_event_notifier_group_fd); | |
2012 | if (error_accounting_status != EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK) { | |
2013 | ERR("Failed to initialize event notifier error accounting for kernel tracer"); | |
2014 | error_code_ret = LTTNG_ERR_EVENT_NOTIFIER_ERROR_ACCOUNTING; | |
2015 | goto error_modules; | |
2016 | } | |
2017 | ||
352b58f5 JR |
2018 | kernel_token_to_event_notifier_rule_ht = cds_lfht_new( |
2019 | DEFAULT_HT_SIZE, 1, 0, | |
2020 | CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, | |
2021 | NULL); | |
2022 | if (!kernel_token_to_event_notifier_rule_ht) { | |
2023 | goto error_token_ht; | |
2024 | } | |
2025 | } | |
2026 | ||
2027 | DBG("Kernel tracer initialized: kernel tracer fd = %d, event notifier group fd = %d, event notifier group notification fd = %d", | |
2028 | kernel_tracer_fd, kernel_tracer_event_notifier_group_fd, | |
2029 | kernel_tracer_event_notifier_group_notification_fd); | |
7d268848 MD |
2030 | |
2031 | ret = syscall_init_table(kernel_tracer_fd); | |
2032 | if (ret < 0) { | |
2033 | ERR("Unable to populate syscall table. Syscall tracing won't " | |
2034 | "work for this session daemon."); | |
2035 | } | |
352b58f5 | 2036 | |
7d268848 MD |
2037 | return 0; |
2038 | ||
2039 | error_version: | |
2040 | modprobe_remove_lttng_control(); | |
2041 | ret = close(kernel_tracer_fd); | |
2042 | if (ret) { | |
352b58f5 JR |
2043 | PERROR("Failed to close kernel tracer file descriptor: fd = %d", |
2044 | kernel_tracer_fd); | |
7d268848 | 2045 | } |
6dcf80d3 | 2046 | |
7d268848 MD |
2047 | kernel_tracer_fd = -1; |
2048 | return LTTNG_ERR_KERN_VERSION; | |
2049 | ||
352b58f5 JR |
2050 | |
2051 | error_token_ht: | |
2052 | ret = close(kernel_tracer_event_notifier_group_notification_fd); | |
2053 | if (ret) { | |
2054 | PERROR("Failed to close kernel tracer event notifier group notification file descriptor: fd = %d", | |
2055 | kernel_tracer_event_notifier_group_notification_fd); | |
2056 | } | |
2057 | ||
6dcf80d3 JG |
2058 | kernel_tracer_event_notifier_group_notification_fd = -1; |
2059 | ||
7d268848 | 2060 | error_modules: |
352b58f5 JR |
2061 | ret = close(kernel_tracer_event_notifier_group_fd); |
2062 | if (ret) { | |
2063 | PERROR("Failed to close kernel tracer event notifier group file descriptor: fd = %d", | |
2064 | kernel_tracer_event_notifier_group_fd); | |
2065 | } | |
2066 | ||
6dcf80d3 JG |
2067 | kernel_tracer_event_notifier_group_fd = -1; |
2068 | ||
7d268848 MD |
2069 | ret = close(kernel_tracer_fd); |
2070 | if (ret) { | |
352b58f5 JR |
2071 | PERROR("Failed to close kernel tracer file descriptor: fd = %d", |
2072 | kernel_tracer_fd); | |
7d268848 MD |
2073 | } |
2074 | ||
6dcf80d3 JG |
2075 | kernel_tracer_fd = -1; |
2076 | ||
7d268848 MD |
2077 | error_open: |
2078 | modprobe_remove_lttng_control(); | |
2079 | ||
2080 | error: | |
2081 | WARN("No kernel tracer available"); | |
2082 | kernel_tracer_fd = -1; | |
2083 | if (!is_root) { | |
2084 | return LTTNG_ERR_NEED_ROOT_SESSIOND; | |
2085 | } else { | |
2086 | return LTTNG_ERR_KERN_NA; | |
2087 | } | |
2088 | } | |
2089 | ||
7d268848 MD |
2090 | void cleanup_kernel_tracer(void) |
2091 | { | |
352b58f5 JR |
2092 | DBG2("Closing kernel event notifier group notification file descriptor"); |
2093 | if (kernel_tracer_event_notifier_group_notification_fd >= 0) { | |
b69a1b40 | 2094 | int ret = notification_thread_command_remove_tracer_event_source( |
412d7227 | 2095 | the_notification_thread_handle, |
352b58f5 JR |
2096 | kernel_tracer_event_notifier_group_notification_fd); |
2097 | if (ret != LTTNG_OK) { | |
2098 | ERR("Failed to remove kernel event notifier notification from notification thread"); | |
2099 | } | |
2100 | ||
2101 | ret = close(kernel_tracer_event_notifier_group_notification_fd); | |
2102 | if (ret) { | |
2103 | PERROR("Failed to close kernel event notifier group notification file descriptor: fd = %d", | |
2104 | kernel_tracer_event_notifier_group_notification_fd); | |
2105 | } | |
2106 | ||
2107 | kernel_tracer_event_notifier_group_notification_fd = -1; | |
2108 | } | |
2109 | ||
2110 | if (kernel_token_to_event_notifier_rule_ht) { | |
b69a1b40 JG |
2111 | const int ret = cds_lfht_destroy( |
2112 | kernel_token_to_event_notifier_rule_ht, NULL); | |
a0377dfe | 2113 | LTTNG_ASSERT(ret == 0); |
352b58f5 JR |
2114 | } |
2115 | ||
2116 | DBG2("Closing kernel event notifier group file descriptor"); | |
2117 | if (kernel_tracer_event_notifier_group_fd >= 0) { | |
b69a1b40 JG |
2118 | const int ret = close(kernel_tracer_event_notifier_group_fd); |
2119 | ||
352b58f5 JR |
2120 | if (ret) { |
2121 | PERROR("Failed to close kernel event notifier group file descriptor: fd = %d", | |
2122 | kernel_tracer_event_notifier_group_fd); | |
2123 | } | |
2124 | ||
2125 | kernel_tracer_event_notifier_group_fd = -1; | |
2126 | } | |
7d268848 MD |
2127 | |
2128 | DBG2("Closing kernel fd"); | |
2129 | if (kernel_tracer_fd >= 0) { | |
b69a1b40 JG |
2130 | const int ret = close(kernel_tracer_fd); |
2131 | ||
7d268848 | 2132 | if (ret) { |
352b58f5 JR |
2133 | PERROR("Failed to close kernel tracer file descriptor: fd = %d", |
2134 | kernel_tracer_fd); | |
7d268848 | 2135 | } |
352b58f5 | 2136 | |
7d268848 MD |
2137 | kernel_tracer_fd = -1; |
2138 | } | |
352b58f5 | 2139 | |
7d268848 MD |
2140 | free(syscall_table); |
2141 | } | |
2142 | ||
7d268848 MD |
2143 | bool kernel_tracer_is_initialized(void) |
2144 | { | |
2145 | return kernel_tracer_fd >= 0; | |
2146 | } | |
bca212a2 MD |
2147 | |
2148 | /* | |
2149 | * Clear a kernel session. | |
2150 | * | |
2151 | * Return LTTNG_OK on success or else an LTTng error code. | |
2152 | */ | |
2153 | enum lttng_error_code kernel_clear_session(struct ltt_session *session) | |
2154 | { | |
2155 | int ret; | |
2156 | enum lttng_error_code status = LTTNG_OK; | |
2157 | struct consumer_socket *socket; | |
2158 | struct lttng_ht_iter iter; | |
2159 | struct ltt_kernel_session *ksess = session->kernel_session; | |
2160 | ||
a0377dfe FD |
2161 | LTTNG_ASSERT(ksess); |
2162 | LTTNG_ASSERT(ksess->consumer); | |
bca212a2 MD |
2163 | |
2164 | DBG("Clear kernel session %s (session %" PRIu64 ")", | |
2165 | session->name, session->id); | |
2166 | ||
2167 | rcu_read_lock(); | |
2168 | ||
2169 | if (ksess->active) { | |
2170 | ERR("Expecting inactive session %s (%" PRIu64 ")", session->name, session->id); | |
2171 | status = LTTNG_ERR_FATAL; | |
2172 | goto end; | |
2173 | } | |
2174 | ||
2175 | /* | |
2176 | * Note that this loop will end after one iteration given that there is | |
2177 | * only one kernel consumer. | |
2178 | */ | |
2179 | cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter, | |
2180 | socket, node.node) { | |
2181 | struct ltt_kernel_channel *chan; | |
2182 | ||
2183 | /* For each channel, ask the consumer to clear it. */ | |
2184 | cds_list_for_each_entry(chan, &ksess->channel_list.head, list) { | |
2185 | DBG("Clear kernel channel %" PRIu64 ", session %s", | |
2186 | chan->key, session->name); | |
2187 | ret = consumer_clear_channel(socket, chan->key); | |
2188 | if (ret < 0) { | |
2189 | goto error; | |
2190 | } | |
2191 | } | |
2192 | ||
2193 | if (!ksess->metadata) { | |
2194 | /* | |
2195 | * Nothing to do for the metadata. | |
2196 | * This is a snapshot session. | |
2197 | * The metadata is genererated on the fly. | |
2198 | */ | |
2199 | continue; | |
2200 | } | |
2201 | ||
2202 | /* | |
2203 | * Clear the metadata channel. | |
2204 | * Metadata channel is not cleared per se but we still need to | |
2205 | * perform a rotation operation on it behind the scene. | |
2206 | */ | |
2207 | ret = consumer_clear_channel(socket, ksess->metadata->key); | |
2208 | if (ret < 0) { | |
2209 | goto error; | |
2210 | } | |
2211 | } | |
2212 | ||
2213 | goto end; | |
2214 | error: | |
2215 | switch (-ret) { | |
2216 | case LTTCOMM_CONSUMERD_RELAYD_CLEAR_DISALLOWED: | |
2217 | status = LTTNG_ERR_CLEAR_RELAY_DISALLOWED; | |
2218 | break; | |
2219 | default: | |
2220 | status = LTTNG_ERR_CLEAR_FAIL_CONSUMER; | |
2221 | break; | |
2222 | } | |
2223 | end: | |
2224 | rcu_read_unlock(); | |
2225 | return status; | |
2226 | } | |
352b58f5 JR |
2227 | |
2228 | enum lttng_error_code kernel_create_event_notifier_group_notification_fd( | |
2229 | int *event_notifier_group_notification_fd) | |
2230 | { | |
2231 | int local_fd = -1, ret; | |
2232 | enum lttng_error_code error_code_ret; | |
2233 | ||
a0377dfe | 2234 | LTTNG_ASSERT(event_notifier_group_notification_fd); |
352b58f5 JR |
2235 | |
2236 | ret = kernctl_create_event_notifier_group_notification_fd( | |
2237 | kernel_tracer_event_notifier_group_fd); | |
2238 | if (ret < 0) { | |
2239 | PERROR("Failed to create kernel event notifier group notification file descriptor"); | |
2240 | error_code_ret = LTTNG_ERR_EVENT_NOTIFIER_GROUP_NOTIFICATION_FD; | |
2241 | goto error; | |
2242 | } | |
2243 | ||
2244 | local_fd = ret; | |
2245 | ||
2246 | /* Prevent fd duplication after execlp(). */ | |
2247 | ret = fcntl(local_fd, F_SETFD, FD_CLOEXEC); | |
2248 | if (ret < 0) { | |
2249 | PERROR("Failed to set FD_CLOEXEC on kernel event notifier group notification file descriptor: fd = %d", | |
2250 | local_fd); | |
2251 | error_code_ret = LTTNG_ERR_EVENT_NOTIFIER_GROUP_NOTIFICATION_FD; | |
2252 | goto error; | |
2253 | } | |
2254 | ||
2255 | DBG("Created kernel notifier group notification file descriptor: fd = %d", | |
2256 | local_fd); | |
2257 | error_code_ret = LTTNG_OK; | |
2258 | *event_notifier_group_notification_fd = local_fd; | |
2259 | local_fd = -1; | |
2260 | ||
2261 | error: | |
2262 | if (local_fd >= 0) { | |
2263 | ret = close(local_fd); | |
2264 | if (ret) { | |
2265 | PERROR("Failed to close kernel event notifier group notification file descriptor: fd = %d", | |
2266 | local_fd); | |
2267 | } | |
2268 | } | |
2269 | ||
2270 | return error_code_ret; | |
2271 | } | |
2272 | ||
2273 | enum lttng_error_code kernel_destroy_event_notifier_group_notification_fd( | |
2274 | int event_notifier_group_notification_fd) | |
2275 | { | |
2276 | enum lttng_error_code ret_code = LTTNG_OK; | |
2277 | ||
2278 | DBG("Closing event notifier group notification file descriptor: fd = %d", | |
2279 | event_notifier_group_notification_fd); | |
2280 | if (event_notifier_group_notification_fd >= 0) { | |
2281 | const int ret = close(event_notifier_group_notification_fd); | |
2282 | if (ret) { | |
2283 | PERROR("Failed to close event notifier group notification file descriptor: fd = %d", | |
2284 | event_notifier_group_notification_fd); | |
2285 | } | |
2286 | } | |
2287 | ||
2288 | return ret_code; | |
2289 | } | |
2290 | ||
2291 | static | |
2292 | unsigned long hash_trigger(const struct lttng_trigger *trigger) | |
2293 | { | |
2294 | const struct lttng_condition *condition = | |
2295 | lttng_trigger_get_const_condition(trigger); | |
2296 | ||
2297 | return lttng_condition_hash(condition); | |
2298 | } | |
2299 | ||
2300 | static | |
2301 | int match_trigger(struct cds_lfht_node *node, const void *key) | |
2302 | { | |
2303 | const struct ltt_kernel_event_notifier_rule *event_notifier_rule; | |
7966af57 | 2304 | const struct lttng_trigger *trigger = (lttng_trigger *) key; |
352b58f5 JR |
2305 | |
2306 | event_notifier_rule = caa_container_of(node, | |
2307 | const struct ltt_kernel_event_notifier_rule, ht_node); | |
2308 | ||
2309 | return lttng_trigger_is_equal(trigger, event_notifier_rule->trigger); | |
2310 | } | |
2311 | ||
2312 | static enum lttng_error_code kernel_create_event_notifier_rule( | |
2313 | struct lttng_trigger *trigger, | |
2314 | const struct lttng_credentials *creds, uint64_t token) | |
2315 | { | |
2316 | int err, fd, ret = 0; | |
2317 | enum lttng_error_code error_code_ret; | |
2318 | enum lttng_condition_status condition_status; | |
2319 | enum lttng_condition_type condition_type; | |
2320 | enum lttng_event_rule_type event_rule_type; | |
2321 | struct ltt_kernel_event_notifier_rule *event_notifier_rule; | |
b8e2fb80 | 2322 | struct lttng_kernel_abi_event_notifier kernel_event_notifier = {}; |
bbd6675c | 2323 | unsigned int capture_bytecode_count = 0, i; |
352b58f5 JR |
2324 | const struct lttng_condition *condition = NULL; |
2325 | const struct lttng_event_rule *event_rule = NULL; | |
bbd6675c | 2326 | enum lttng_condition_status cond_status; |
352b58f5 | 2327 | |
a0377dfe | 2328 | LTTNG_ASSERT(trigger); |
352b58f5 JR |
2329 | |
2330 | condition = lttng_trigger_get_const_condition(trigger); | |
a0377dfe | 2331 | LTTNG_ASSERT(condition); |
352b58f5 JR |
2332 | |
2333 | condition_type = lttng_condition_get_type(condition); | |
a0377dfe | 2334 | LTTNG_ASSERT(condition_type == LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES); |
352b58f5 JR |
2335 | |
2336 | /* Does not acquire a reference. */ | |
8dbb86b8 | 2337 | condition_status = lttng_condition_event_rule_matches_get_rule( |
352b58f5 | 2338 | condition, &event_rule); |
a0377dfe FD |
2339 | LTTNG_ASSERT(condition_status == LTTNG_CONDITION_STATUS_OK); |
2340 | LTTNG_ASSERT(event_rule); | |
352b58f5 JR |
2341 | |
2342 | event_rule_type = lttng_event_rule_get_type(event_rule); | |
a0377dfe | 2343 | LTTNG_ASSERT(event_rule_type != LTTNG_EVENT_RULE_TYPE_UNKNOWN); |
352b58f5 JR |
2344 | |
2345 | error_code_ret = trace_kernel_create_event_notifier_rule(trigger, token, | |
8dbb86b8 JR |
2346 | lttng_condition_event_rule_matches_get_error_counter_index( |
2347 | condition), | |
352b58f5 JR |
2348 | &event_notifier_rule); |
2349 | if (error_code_ret != LTTNG_OK) { | |
2350 | goto error; | |
2351 | } | |
2352 | ||
2353 | error_code_ret = trace_kernel_init_event_notifier_from_event_rule( | |
2354 | event_rule, &kernel_event_notifier); | |
2355 | if (error_code_ret != LTTNG_OK) { | |
b5e3b044 | 2356 | goto free_event; |
352b58f5 JR |
2357 | } |
2358 | ||
2359 | kernel_event_notifier.event.token = event_notifier_rule->token; | |
90aa04a1 | 2360 | kernel_event_notifier.error_counter_idx = |
8dbb86b8 JR |
2361 | lttng_condition_event_rule_matches_get_error_counter_index( |
2362 | condition); | |
352b58f5 JR |
2363 | |
2364 | fd = kernctl_create_event_notifier( | |
2365 | kernel_tracer_event_notifier_group_fd, | |
2366 | &kernel_event_notifier); | |
2367 | if (fd < 0) { | |
2368 | switch (-fd) { | |
2369 | case EEXIST: | |
2370 | error_code_ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
2371 | break; | |
2372 | case ENOSYS: | |
2373 | WARN("Failed to create kernel event notifier: not notifier type not implemented"); | |
2374 | error_code_ret = LTTNG_ERR_KERN_EVENT_ENOSYS; | |
2375 | break; | |
2376 | case ENOENT: | |
2377 | WARN("Failed to create kernel event notifier: not found: name = '%s'", | |
2378 | kernel_event_notifier.event.name); | |
2379 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
2380 | break; | |
2381 | default: | |
2382 | PERROR("Failed to create kernel event notifier: error code = %d, name = '%s'", | |
2383 | fd, kernel_event_notifier.event.name); | |
2384 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
2385 | } | |
2386 | goto free_event; | |
2387 | } | |
2388 | ||
2389 | event_notifier_rule->fd = fd; | |
2390 | /* Prevent fd duplication after execlp(). */ | |
2391 | err = fcntl(event_notifier_rule->fd, F_SETFD, FD_CLOEXEC); | |
2392 | if (err < 0) { | |
2393 | PERROR("Failed to set FD_CLOEXEC on kernel event notifier file descriptor: fd = %d", | |
2394 | fd); | |
2395 | error_code_ret = LTTNG_ERR_FATAL; | |
2396 | goto set_cloexec_error; | |
2397 | } | |
2398 | ||
2399 | if (event_notifier_rule->filter) { | |
2400 | err = kernctl_filter(event_notifier_rule->fd, event_notifier_rule->filter); | |
2401 | if (err < 0) { | |
2402 | switch (-err) { | |
2403 | case ENOMEM: | |
2404 | error_code_ret = LTTNG_ERR_FILTER_NOMEM; | |
2405 | break; | |
2406 | default: | |
2407 | error_code_ret = LTTNG_ERR_FILTER_INVAL; | |
2408 | break; | |
2409 | } | |
2410 | goto filter_error; | |
2411 | } | |
2412 | } | |
2413 | ||
2414 | if (lttng_event_rule_get_type(event_rule) == | |
46fd07ac | 2415 | LTTNG_EVENT_RULE_TYPE_KERNEL_UPROBE) { |
352b58f5 JR |
2416 | ret = userspace_probe_event_rule_add_callsites( |
2417 | event_rule, creds, event_notifier_rule->fd); | |
2418 | if (ret) { | |
2419 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
2420 | goto add_callsite_error; | |
2421 | } | |
2422 | } | |
2423 | ||
d602bd6a | 2424 | /* Set the capture bytecode if any. */ |
8dbb86b8 | 2425 | cond_status = lttng_condition_event_rule_matches_get_capture_descriptor_count( |
bbd6675c | 2426 | condition, &capture_bytecode_count); |
a0377dfe | 2427 | LTTNG_ASSERT(cond_status == LTTNG_CONDITION_STATUS_OK); |
bbd6675c JR |
2428 | |
2429 | for (i = 0; i < capture_bytecode_count; i++) { | |
2430 | const struct lttng_bytecode *capture_bytecode = | |
8dbb86b8 | 2431 | lttng_condition_event_rule_matches_get_capture_bytecode_at_index( |
bbd6675c JR |
2432 | condition, i); |
2433 | ||
2434 | if (capture_bytecode == NULL) { | |
2435 | ERR("Unexpected NULL capture bytecode on condition"); | |
2436 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
e8b1187d | 2437 | goto capture_error; |
bbd6675c JR |
2438 | } |
2439 | ||
2440 | ret = kernctl_capture(event_notifier_rule->fd, capture_bytecode); | |
2441 | if (ret < 0) { | |
2442 | ERR("Failed to set capture bytecode on event notifier rule fd: fd = %d", | |
2443 | event_notifier_rule->fd); | |
2444 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
e8b1187d | 2445 | goto capture_error; |
bbd6675c JR |
2446 | } |
2447 | } | |
2448 | ||
352b58f5 JR |
2449 | err = kernctl_enable(event_notifier_rule->fd); |
2450 | if (err < 0) { | |
2451 | switch (-err) { | |
2452 | case EEXIST: | |
2453 | error_code_ret = LTTNG_ERR_KERN_EVENT_EXIST; | |
2454 | break; | |
2455 | default: | |
2456 | PERROR("enable kernel event notifier"); | |
2457 | error_code_ret = LTTNG_ERR_KERN_ENABLE_FAIL; | |
2458 | break; | |
2459 | } | |
2460 | goto enable_error; | |
2461 | } | |
2462 | ||
2463 | /* Add trigger to kernel token mapping in the hash table. */ | |
2464 | rcu_read_lock(); | |
2465 | cds_lfht_add(kernel_token_to_event_notifier_rule_ht, hash_trigger(trigger), | |
2466 | &event_notifier_rule->ht_node); | |
2467 | rcu_read_unlock(); | |
2468 | ||
2469 | DBG("Created kernel event notifier: name = '%s', fd = %d", | |
2470 | kernel_event_notifier.event.name, | |
2471 | event_notifier_rule->fd); | |
2472 | ||
2473 | return LTTNG_OK; | |
2474 | ||
e8b1187d | 2475 | capture_error: |
352b58f5 JR |
2476 | add_callsite_error: |
2477 | enable_error: | |
2478 | set_cloexec_error: | |
2479 | filter_error: | |
2480 | { | |
2481 | const int close_ret = close(event_notifier_rule->fd); | |
2482 | ||
2483 | if (close_ret) { | |
2484 | PERROR("Failed to close kernel event notifier file descriptor: fd = %d", | |
2485 | event_notifier_rule->fd); | |
2486 | } | |
2487 | } | |
2488 | free_event: | |
2489 | free(event_notifier_rule); | |
2490 | error: | |
2491 | return error_code_ret; | |
2492 | } | |
2493 | ||
2494 | enum lttng_error_code kernel_register_event_notifier( | |
2495 | struct lttng_trigger *trigger, | |
2496 | const struct lttng_credentials *cmd_creds) | |
2497 | { | |
2498 | enum lttng_error_code ret; | |
2499 | enum lttng_condition_status status; | |
2500 | enum lttng_domain_type domain_type; | |
2501 | const struct lttng_event_rule *event_rule; | |
2502 | const struct lttng_condition *const condition = | |
2503 | lttng_trigger_get_const_condition(trigger); | |
2504 | const uint64_t token = lttng_trigger_get_tracer_token(trigger); | |
2505 | ||
a0377dfe | 2506 | LTTNG_ASSERT(condition); |
352b58f5 JR |
2507 | |
2508 | /* Does not acquire a reference to the event rule. */ | |
8dbb86b8 | 2509 | status = lttng_condition_event_rule_matches_get_rule( |
352b58f5 | 2510 | condition, &event_rule); |
a0377dfe | 2511 | LTTNG_ASSERT(status == LTTNG_CONDITION_STATUS_OK); |
352b58f5 JR |
2512 | |
2513 | domain_type = lttng_event_rule_get_domain_type(event_rule); | |
a0377dfe | 2514 | LTTNG_ASSERT(domain_type == LTTNG_DOMAIN_KERNEL); |
352b58f5 JR |
2515 | |
2516 | ret = kernel_create_event_notifier_rule(trigger, cmd_creds, token); | |
2517 | if (ret != LTTNG_OK) { | |
124dda43 | 2518 | ERR("Failed to create kernel event notifier rule"); |
352b58f5 JR |
2519 | } |
2520 | ||
2521 | return ret; | |
2522 | } | |
2523 | ||
2524 | enum lttng_error_code kernel_unregister_event_notifier( | |
2525 | const struct lttng_trigger *trigger) | |
2526 | { | |
2527 | struct ltt_kernel_event_notifier_rule *token_event_rule_element; | |
2528 | struct cds_lfht_node *node; | |
2529 | struct cds_lfht_iter iter; | |
2530 | enum lttng_error_code error_code_ret; | |
2531 | int ret; | |
2532 | ||
2533 | rcu_read_lock(); | |
2534 | ||
2535 | cds_lfht_lookup(kernel_token_to_event_notifier_rule_ht, | |
2536 | hash_trigger(trigger), match_trigger, trigger, &iter); | |
2537 | ||
2538 | node = cds_lfht_iter_get_node(&iter); | |
2539 | if (!node) { | |
2540 | error_code_ret = LTTNG_ERR_TRIGGER_NOT_FOUND; | |
2541 | goto error; | |
2542 | } | |
2543 | ||
2544 | token_event_rule_element = caa_container_of(node, | |
2545 | struct ltt_kernel_event_notifier_rule, ht_node); | |
2546 | ||
2547 | ret = kernel_disable_event_notifier_rule(token_event_rule_element); | |
2548 | if (ret) { | |
2549 | error_code_ret = LTTNG_ERR_FATAL; | |
2550 | goto error; | |
2551 | } | |
2552 | ||
2553 | trace_kernel_destroy_event_notifier_rule(token_event_rule_element); | |
2554 | error_code_ret = LTTNG_OK; | |
2555 | ||
2556 | error: | |
2557 | rcu_read_unlock(); | |
2558 | ||
2559 | return error_code_ret; | |
2560 | } | |
2561 | ||
2562 | int kernel_get_notification_fd(void) | |
2563 | { | |
2564 | return kernel_tracer_event_notifier_group_notification_fd; | |
2565 | } |