Implement consumer ring buffer position sampling
[lttng-tools.git] / src / bin / lttng-sessiond / trace-kernel.c
CommitLineData
54012638
DG
1/*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 *
d14d33bf
AM
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License, version 2 only,
6 * as published by the Free Software Foundation.
54012638
DG
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
d14d33bf
AM
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
54012638
DG
16 */
17
6c1c0768 18#define _LGPL_SOURCE
54012638
DG
19#include <stdio.h>
20#include <stdlib.h>
21#include <string.h>
c363b55d 22#include <unistd.h>
54012638 23
990570ed
DG
24#include <common/common.h>
25#include <common/defaults.h>
1e307fab 26
00e2e675 27#include "consumer.h"
62499ad6 28#include "trace-kernel.h"
e9404c27
JG
29#include "lttng-sessiond.h"
30#include "notification-thread-commands.h"
54012638 31
19e70852 32/*
050349bb 33 * Find the channel name for the given kernel session.
19e70852 34 */
62499ad6 35struct ltt_kernel_channel *trace_kernel_get_channel_by_name(
19e70852
DG
36 char *name, struct ltt_kernel_session *session)
37{
38 struct ltt_kernel_channel *chan;
39
0525e9ae
DG
40 assert(session);
41 assert(name);
19e70852 42
85076754
MD
43 /*
44 * If we receive an empty string for channel name, it means the
45 * default channel name is requested.
46 */
47 if (name[0] == '\0')
48 name = DEFAULT_CHANNEL_NAME;
49
54d01ffb
DG
50 DBG("Trying to find channel %s", name);
51
19e70852
DG
52 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
53 if (strcmp(name, chan->channel->name) == 0) {
54 DBG("Found channel by name %s", name);
55 return chan;
56 }
57 }
58
19e70852
DG
59 return NULL;
60}
61
00a62084
MD
62/*
63 * Find the event for the given channel.
64 */
65struct ltt_kernel_event *trace_kernel_find_event(
66 char *name, struct ltt_kernel_channel *channel,
67 enum lttng_event_type type,
68 struct lttng_filter_bytecode *filter)
69{
70 struct ltt_kernel_event *ev;
71 int found = 0;
72
73 assert(name);
74 assert(channel);
75
76 cds_list_for_each_entry(ev, &channel->events_list.head, list) {
77 if (type != LTTNG_EVENT_ALL && ev->type != type) {
78 continue;
79 }
80 if (strcmp(name, ev->event->name)) {
81 continue;
82 }
83 if ((ev->filter && !filter) || (!ev->filter && filter)) {
84 continue;
85 }
86 if (ev->filter && filter) {
87 if (ev->filter->len != filter->len ||
88 memcmp(ev->filter->data, filter->data,
89 filter->len) != 0) {
90 continue;
91 }
92 }
93 found = 1;
94 break;
95 }
96 if (found) {
97 DBG("Found event %s for channel %s", name,
98 channel->channel->name);
99 return ev;
100 } else {
101 return NULL;
102 }
103}
104
19e70852 105/*
050349bb 106 * Find the event name for the given channel.
19e70852 107 */
62499ad6 108struct ltt_kernel_event *trace_kernel_get_event_by_name(
d0ae4ea8
MD
109 char *name, struct ltt_kernel_channel *channel,
110 enum lttng_event_type type)
19e70852
DG
111{
112 struct ltt_kernel_event *ev;
00a62084 113 int found = 0;
19e70852 114
0525e9ae
DG
115 assert(name);
116 assert(channel);
19e70852
DG
117
118 cds_list_for_each_entry(ev, &channel->events_list.head, list) {
00a62084 119 if (type != LTTNG_EVENT_ALL && ev->type != type) {
d0ae4ea8 120 continue;
19e70852 121 }
00a62084
MD
122 if (strcmp(name, ev->event->name)) {
123 continue;
124 }
125 found = 1;
126 break;
127 }
128 if (found) {
129 DBG("Found event %s for channel %s", name,
130 channel->channel->name);
131 return ev;
132 } else {
133 return NULL;
19e70852 134 }
19e70852
DG
135}
136
54012638 137/*
050349bb 138 * Allocate and initialize a kernel session data structure.
54012638 139 *
050349bb 140 * Return pointer to structure or NULL.
54012638 141 */
dec56f6c 142struct ltt_kernel_session *trace_kernel_create_session(void)
54012638 143{
a4b92340 144 struct ltt_kernel_session *lks = NULL;
54012638
DG
145
146 /* Allocate a new ltt kernel session */
ba7f0ae5 147 lks = zmalloc(sizeof(struct ltt_kernel_session));
54012638 148 if (lks == NULL) {
df0f840b 149 PERROR("create kernel session zmalloc");
a4b92340 150 goto alloc_error;
54012638
DG
151 }
152
153 /* Init data structure */
03550b58
MD
154 lks->fd = -1;
155 lks->metadata_stream_fd = -1;
54012638
DG
156 lks->channel_count = 0;
157 lks->stream_count_global = 0;
158 lks->metadata = NULL;
159 CDS_INIT_LIST_HEAD(&lks->channel_list.head);
160
00e2e675
DG
161 lks->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
162 if (lks->consumer == NULL) {
163 goto error;
164 }
165
54012638
DG
166 return lks;
167
168error:
a4b92340
DG
169 free(lks);
170
171alloc_error:
54012638
DG
172 return NULL;
173}
174
175/*
050349bb 176 * Allocate and initialize a kernel channel data structure.
54012638 177 *
050349bb 178 * Return pointer to structure or NULL.
54012638 179 */
00e2e675 180struct ltt_kernel_channel *trace_kernel_create_channel(
fdd9eb17 181 struct lttng_channel *chan)
54012638 182{
54012638 183 struct ltt_kernel_channel *lkc;
e9404c27 184 struct lttng_channel_extended *extended;
54012638 185
0525e9ae
DG
186 assert(chan);
187
ba7f0ae5 188 lkc = zmalloc(sizeof(struct ltt_kernel_channel));
f3ed775e 189 if (lkc == NULL) {
df0f840b 190 PERROR("ltt_kernel_channel zmalloc");
54012638
DG
191 goto error;
192 }
193
ba7f0ae5 194 lkc->channel = zmalloc(sizeof(struct lttng_channel));
f3ed775e 195 if (lkc->channel == NULL) {
df0f840b 196 PERROR("lttng_channel zmalloc");
e9404c27
JG
197 goto error;
198 }
199
200 extended = zmalloc(sizeof(struct lttng_channel_extended));
201 if (!extended) {
202 PERROR("lttng_channel_channel zmalloc");
f3ed775e
DG
203 goto error;
204 }
205 memcpy(lkc->channel, chan, sizeof(struct lttng_channel));
e9404c27
JG
206 memcpy(extended, chan->attr.extended.ptr, sizeof(struct lttng_channel_extended));
207 lkc->channel->attr.extended.ptr = extended;
208 extended = NULL;
54012638 209
85076754
MD
210 /*
211 * If we receive an empty string for channel name, it means the
212 * default channel name is requested.
213 */
214 if (chan->name[0] == '\0') {
215 strncpy(lkc->channel->name, DEFAULT_CHANNEL_NAME,
216 sizeof(lkc->channel->name));
217 }
bd722d76 218 lkc->channel->name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
85076754 219
03550b58 220 lkc->fd = -1;
54012638 221 lkc->stream_count = 0;
cbbbb275 222 lkc->event_count = 0;
d36b8583 223 lkc->enabled = 1;
54012638
DG
224 /* Init linked list */
225 CDS_INIT_LIST_HEAD(&lkc->events_list.head);
226 CDS_INIT_LIST_HEAD(&lkc->stream_list.head);
645328ae 227 CDS_INIT_LIST_HEAD(&lkc->ctx_list);
54012638
DG
228
229 return lkc;
230
231error:
e9404c27
JG
232 if (lkc) {
233 free(lkc->channel);
234 }
235 free(extended);
236 free(lkc);
54012638
DG
237 return NULL;
238}
239
645328ae
DG
240/*
241 * Allocate and init a kernel context object.
242 *
243 * Return the allocated object or NULL on error.
244 */
245struct ltt_kernel_context *trace_kernel_create_context(
246 struct lttng_kernel_context *ctx)
247{
248 struct ltt_kernel_context *kctx;
249
250 kctx = zmalloc(sizeof(*kctx));
251 if (!kctx) {
252 PERROR("zmalloc kernel context");
253 goto error;
254 }
255
256 if (ctx) {
257 memcpy(&kctx->ctx, ctx, sizeof(kctx->ctx));
258 }
259
7b9445b3
DG
260 CDS_INIT_LIST_HEAD(&kctx->list);
261
645328ae
DG
262error:
263 return kctx;
264}
265
54012638 266/*
050349bb 267 * Allocate and initialize a kernel event. Set name and event type.
a969e101 268 * We own filter_expression, and filter.
54012638 269 *
050349bb 270 * Return pointer to structure or NULL.
54012638 271 */
00a62084
MD
272struct ltt_kernel_event *trace_kernel_create_event(struct lttng_event *ev,
273 char *filter_expression, struct lttng_filter_bytecode *filter)
54012638
DG
274{
275 struct ltt_kernel_event *lke;
276 struct lttng_kernel_event *attr;
277
0525e9ae
DG
278 assert(ev);
279
ba7f0ae5
DG
280 lke = zmalloc(sizeof(struct ltt_kernel_event));
281 attr = zmalloc(sizeof(struct lttng_kernel_event));
54012638 282 if (lke == NULL || attr == NULL) {
df0f840b 283 PERROR("kernel event zmalloc");
54012638
DG
284 goto error;
285 }
286
f3ed775e 287 switch (ev->type) {
7d29a247 288 case LTTNG_EVENT_PROBE:
e6ddca71 289 attr->instrumentation = LTTNG_KERNEL_KPROBE;
7d29a247
DG
290 attr->u.kprobe.addr = ev->attr.probe.addr;
291 attr->u.kprobe.offset = ev->attr.probe.offset;
f3ed775e 292 strncpy(attr->u.kprobe.symbol_name,
dbbb3ec5
DG
293 ev->attr.probe.symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
294 attr->u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
f3ed775e
DG
295 break;
296 case LTTNG_EVENT_FUNCTION:
8f0d098b
MD
297 attr->instrumentation = LTTNG_KERNEL_KRETPROBE;
298 attr->u.kretprobe.addr = ev->attr.probe.addr;
299 attr->u.kretprobe.offset = ev->attr.probe.offset;
8f0d098b 300 strncpy(attr->u.kretprobe.symbol_name,
dbbb3ec5
DG
301 ev->attr.probe.symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
302 attr->u.kretprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
8f0d098b
MD
303 break;
304 case LTTNG_EVENT_FUNCTION_ENTRY:
f3ed775e
DG
305 attr->instrumentation = LTTNG_KERNEL_FUNCTION;
306 strncpy(attr->u.ftrace.symbol_name,
dbbb3ec5
DG
307 ev->attr.ftrace.symbol_name, LTTNG_KERNEL_SYM_NAME_LEN);
308 attr->u.ftrace.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
f3ed775e 309 break;
e6ddca71
DG
310 case LTTNG_EVENT_TRACEPOINT:
311 attr->instrumentation = LTTNG_KERNEL_TRACEPOINT;
f3ed775e 312 break;
a54bd42d
MD
313 case LTTNG_EVENT_SYSCALL:
314 attr->instrumentation = LTTNG_KERNEL_SYSCALL;
0133c199 315 break;
7a3d1328
MD
316 case LTTNG_EVENT_ALL:
317 attr->instrumentation = LTTNG_KERNEL_ALL;
318 break;
f3ed775e
DG
319 default:
320 ERR("Unknown kernel instrumentation type (%d)", ev->type);
321 goto error;
322 }
323
324 /* Copy event name */
dbbb3ec5
DG
325 strncpy(attr->name, ev->name, LTTNG_KERNEL_SYM_NAME_LEN);
326 attr->name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
f3ed775e 327
54012638 328 /* Setting up a kernel event */
03550b58 329 lke->fd = -1;
54012638 330 lke->event = attr;
d36b8583 331 lke->enabled = 1;
00a62084
MD
332 lke->filter_expression = filter_expression;
333 lke->filter = filter;
54012638
DG
334
335 return lke;
336
337error:
a969e101
MD
338 free(filter_expression);
339 free(filter);
a2c0da86
MD
340 free(lke);
341 free(attr);
54012638
DG
342 return NULL;
343}
344
345/*
050349bb 346 * Allocate and initialize a kernel metadata.
54012638 347 *
050349bb 348 * Return pointer to structure or NULL.
54012638 349 */
a4b92340 350struct ltt_kernel_metadata *trace_kernel_create_metadata(void)
54012638 351{
54012638 352 struct ltt_kernel_metadata *lkm;
f3ed775e 353 struct lttng_channel *chan;
54012638 354
ba7f0ae5
DG
355 lkm = zmalloc(sizeof(struct ltt_kernel_metadata));
356 chan = zmalloc(sizeof(struct lttng_channel));
f3ed775e 357 if (lkm == NULL || chan == NULL) {
df0f840b 358 PERROR("kernel metadata zmalloc");
54012638
DG
359 goto error;
360 }
361
362 /* Set default attributes */
f3ed775e 363 chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
3e230f92 364 chan->attr.subbuf_size = default_get_metadata_subbuf_size();
b389abbe 365 chan->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
6bb9e85f
MD
366 chan->attr.switch_timer_interval = DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
367 chan->attr.read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
7d452e12 368 chan->attr.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
54012638
DG
369
370 /* Init metadata */
03550b58 371 lkm->fd = -1;
f3ed775e 372 lkm->conf = chan;
54012638
DG
373
374 return lkm;
375
376error:
a2c0da86
MD
377 free(lkm);
378 free(chan);
54012638
DG
379 return NULL;
380}
381
382/*
050349bb
DG
383 * Allocate and initialize a kernel stream. The stream is set to ACTIVE_FD by
384 * default.
54012638 385 *
050349bb 386 * Return pointer to structure or NULL.
54012638 387 */
00e2e675
DG
388struct ltt_kernel_stream *trace_kernel_create_stream(const char *name,
389 unsigned int count)
54012638 390{
00e2e675 391 int ret;
54012638
DG
392 struct ltt_kernel_stream *lks;
393
0525e9ae
DG
394 assert(name);
395
ba7f0ae5 396 lks = zmalloc(sizeof(struct ltt_kernel_stream));
54012638 397 if (lks == NULL) {
df0f840b 398 PERROR("kernel stream zmalloc");
54012638
DG
399 goto error;
400 }
401
00e2e675 402 /* Set name */
535b8ff4 403 ret = snprintf(lks->name, sizeof(lks->name), "%s_%u", name, count);
00e2e675
DG
404 if (ret < 0) {
405 PERROR("snprintf stream name");
406 goto error;
407 }
408 lks->name[sizeof(lks->name) - 1] = '\0';
409
54012638 410 /* Init stream */
03550b58 411 lks->fd = -1;
54012638 412 lks->state = 0;
ffe60014 413 lks->cpu = count;
54012638
DG
414
415 return lks;
416
417error:
418 return NULL;
419}
c363b55d 420
050349bb
DG
421/*
422 * Cleanup kernel stream structure.
423 */
62499ad6 424void trace_kernel_destroy_stream(struct ltt_kernel_stream *stream)
c363b55d 425{
0525e9ae
DG
426 assert(stream);
427
33a2b854 428 DBG("[trace] Closing stream fd %d", stream->fd);
c363b55d 429 /* Close kernel fd */
03550b58 430 if (stream->fd >= 0) {
c617c0c6
MD
431 int ret;
432
03550b58
MD
433 ret = close(stream->fd);
434 if (ret) {
435 PERROR("close");
436 }
799e2c4f 437 }
c363b55d
DG
438 /* Remove from stream list */
439 cds_list_del(&stream->list);
f9815039 440
c363b55d
DG
441 free(stream);
442}
443
050349bb
DG
444/*
445 * Cleanup kernel event structure.
446 */
62499ad6 447void trace_kernel_destroy_event(struct ltt_kernel_event *event)
c363b55d 448{
0525e9ae
DG
449 assert(event);
450
87eb4ab8 451 if (event->fd >= 0) {
c617c0c6
MD
452 int ret;
453
87eb4ab8
MD
454 DBG("[trace] Closing event fd %d", event->fd);
455 /* Close kernel fd */
799e2c4f
MD
456 ret = close(event->fd);
457 if (ret) {
458 PERROR("close");
459 }
87eb4ab8
MD
460 } else {
461 DBG("[trace] Tearing down event (no associated fd)");
462 }
c363b55d
DG
463
464 /* Remove from event list */
465 cds_list_del(&event->list);
f9815039 466
00a62084
MD
467 free(event->filter_expression);
468 free(event->filter);
469
f9815039 470 free(event->event);
c363b55d
DG
471 free(event);
472}
473
645328ae
DG
474/*
475 * Cleanup kernel context structure.
476 */
477void trace_kernel_destroy_context(struct ltt_kernel_context *ctx)
478{
479 assert(ctx);
480
481 cds_list_del(&ctx->list);
482 free(ctx);
483}
484
050349bb
DG
485/*
486 * Cleanup kernel channel structure.
487 */
62499ad6 488void trace_kernel_destroy_channel(struct ltt_kernel_channel *channel)
c363b55d 489{
af9737e9
DG
490 struct ltt_kernel_stream *stream, *stmp;
491 struct ltt_kernel_event *event, *etmp;
645328ae 492 struct ltt_kernel_context *ctx, *ctmp;
799e2c4f 493 int ret;
e9404c27 494 enum lttng_error_code status;
c363b55d 495
0525e9ae
DG
496 assert(channel);
497
33a2b854 498 DBG("[trace] Closing channel fd %d", channel->fd);
c363b55d 499 /* Close kernel fd */
03550b58
MD
500 if (channel->fd >= 0) {
501 ret = close(channel->fd);
502 if (ret) {
503 PERROR("close");
504 }
799e2c4f 505 }
c363b55d
DG
506
507 /* For each stream in the channel list */
af9737e9 508 cds_list_for_each_entry_safe(stream, stmp, &channel->stream_list.head, list) {
62499ad6 509 trace_kernel_destroy_stream(stream);
c363b55d
DG
510 }
511
512 /* For each event in the channel list */
af9737e9 513 cds_list_for_each_entry_safe(event, etmp, &channel->events_list.head, list) {
62499ad6 514 trace_kernel_destroy_event(event);
c363b55d
DG
515 }
516
645328ae
DG
517 /* For each context in the channel list */
518 cds_list_for_each_entry_safe(ctx, ctmp, &channel->ctx_list, list) {
519 trace_kernel_destroy_context(ctx);
520 }
521
c363b55d
DG
522 /* Remove from channel list */
523 cds_list_del(&channel->list);
f9815039 524
e9404c27
JG
525 status = notification_thread_command_remove_channel(
526 notification_thread_handle,
527 channel->fd, LTTNG_DOMAIN_KERNEL);
528 assert(status == LTTNG_OK);
529 free(channel->channel->attr.extended.ptr);
f9815039 530 free(channel->channel);
c363b55d
DG
531 free(channel);
532}
533
050349bb
DG
534/*
535 * Cleanup kernel metadata structure.
536 */
62499ad6 537void trace_kernel_destroy_metadata(struct ltt_kernel_metadata *metadata)
c363b55d 538{
0525e9ae
DG
539 assert(metadata);
540
33a2b854 541 DBG("[trace] Closing metadata fd %d", metadata->fd);
c363b55d 542 /* Close kernel fd */
03550b58 543 if (metadata->fd >= 0) {
c617c0c6
MD
544 int ret;
545
03550b58
MD
546 ret = close(metadata->fd);
547 if (ret) {
548 PERROR("close");
549 }
799e2c4f 550 }
c363b55d 551
f9815039 552 free(metadata->conf);
c363b55d
DG
553 free(metadata);
554}
555
050349bb 556/*
62499ad6 557 * Cleanup kernel session structure
36b588ed
MD
558 *
559 * Should *NOT* be called with RCU read-side lock held.
050349bb 560 */
62499ad6 561void trace_kernel_destroy_session(struct ltt_kernel_session *session)
c363b55d 562{
af9737e9 563 struct ltt_kernel_channel *channel, *ctmp;
799e2c4f 564 int ret;
c363b55d 565
0525e9ae
DG
566 assert(session);
567
33a2b854 568 DBG("[trace] Closing session fd %d", session->fd);
c363b55d 569 /* Close kernel fds */
03550b58
MD
570 if (session->fd >= 0) {
571 ret = close(session->fd);
572 if (ret) {
573 PERROR("close");
574 }
799e2c4f 575 }
f9815039 576
03550b58 577 if (session->metadata_stream_fd >= 0) {
70dc1c34 578 DBG("[trace] Closing metadata stream fd %d", session->metadata_stream_fd);
799e2c4f
MD
579 ret = close(session->metadata_stream_fd);
580 if (ret) {
581 PERROR("close");
582 }
70dc1c34 583 }
c363b55d 584
d36b8583 585 if (session->metadata != NULL) {
62499ad6 586 trace_kernel_destroy_metadata(session->metadata);
d36b8583 587 }
c363b55d 588
af9737e9 589 cds_list_for_each_entry_safe(channel, ctmp, &session->channel_list.head, list) {
62499ad6 590 trace_kernel_destroy_channel(channel);
c363b55d
DG
591 }
592
00e2e675 593 /* Wipe consumer output object */
6addfa37 594 consumer_output_put(session->consumer);
00e2e675 595
c363b55d
DG
596 free(session);
597}
This page took 0.133266 seconds and 4 git commands to generate.