| 1 | /* |
| 2 | * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca> |
| 3 | * |
| 4 | * SPDX-License-Identifier: GPL-2.0-only |
| 5 | * |
| 6 | */ |
| 7 | |
| 8 | #define _LGPL_SOURCE |
| 9 | #include <stdio.h> |
| 10 | #include <stdlib.h> |
| 11 | #include <string.h> |
| 12 | #include <unistd.h> |
| 13 | |
| 14 | #include <lttng/event.h> |
| 15 | #include <lttng/lttng-error.h> |
| 16 | #include <lttng/kernel-probe.h> |
| 17 | #include <lttng/userspace-probe.h> |
| 18 | #include <lttng/userspace-probe-internal.h> |
| 19 | #include <lttng/event-rule/event-rule.h> |
| 20 | #include <lttng/event-rule/event-rule-internal.h> |
| 21 | #include <lttng/event-rule/kernel-probe.h> |
| 22 | #include <lttng/event-rule/kernel-probe-internal.h> |
| 23 | #include <lttng/event-rule/kernel-syscall.h> |
| 24 | #include <lttng/event-rule/kernel-syscall-internal.h> |
| 25 | #include <lttng/event-rule/tracepoint.h> |
| 26 | #include <lttng/event-rule/tracepoint-internal.h> |
| 27 | #include <lttng/event-rule/userspace-probe-internal.h> |
| 28 | #include <common/common.h> |
| 29 | #include <common/defaults.h> |
| 30 | #include <common/trace-chunk.h> |
| 31 | #include <common/macros.h> |
| 32 | |
| 33 | #include "consumer.h" |
| 34 | #include "trace-kernel.h" |
| 35 | #include "lttng-sessiond.h" |
| 36 | #include "notification-thread-commands.h" |
| 37 | |
| 38 | /* |
| 39 | * Find the channel name for the given kernel session. |
| 40 | */ |
| 41 | struct ltt_kernel_channel *trace_kernel_get_channel_by_name( |
| 42 | const char *name, struct ltt_kernel_session *session) |
| 43 | { |
| 44 | struct ltt_kernel_channel *chan; |
| 45 | |
| 46 | assert(session); |
| 47 | assert(name); |
| 48 | |
| 49 | /* |
| 50 | * If we receive an empty string for channel name, it means the |
| 51 | * default channel name is requested. |
| 52 | */ |
| 53 | if (name[0] == '\0') |
| 54 | name = DEFAULT_CHANNEL_NAME; |
| 55 | |
| 56 | DBG("Trying to find channel %s", name); |
| 57 | |
| 58 | cds_list_for_each_entry(chan, &session->channel_list.head, list) { |
| 59 | if (strcmp(name, chan->channel->name) == 0) { |
| 60 | DBG("Found channel by name %s", name); |
| 61 | return chan; |
| 62 | } |
| 63 | } |
| 64 | |
| 65 | return NULL; |
| 66 | } |
| 67 | |
| 68 | /* |
| 69 | * Find the event for the given channel. |
| 70 | */ |
| 71 | struct ltt_kernel_event *trace_kernel_find_event( |
| 72 | char *name, struct ltt_kernel_channel *channel, |
| 73 | enum lttng_event_type type, |
| 74 | struct lttng_bytecode *filter) |
| 75 | { |
| 76 | struct ltt_kernel_event *ev; |
| 77 | int found = 0; |
| 78 | |
| 79 | assert(name); |
| 80 | assert(channel); |
| 81 | |
| 82 | cds_list_for_each_entry(ev, &channel->events_list.head, list) { |
| 83 | if (type != LTTNG_EVENT_ALL && ev->type != type) { |
| 84 | continue; |
| 85 | } |
| 86 | if (strcmp(name, ev->event->name)) { |
| 87 | continue; |
| 88 | } |
| 89 | if ((ev->filter && !filter) || (!ev->filter && filter)) { |
| 90 | continue; |
| 91 | } |
| 92 | if (ev->filter && filter) { |
| 93 | if (ev->filter->len != filter->len || |
| 94 | memcmp(ev->filter->data, filter->data, |
| 95 | filter->len) != 0) { |
| 96 | continue; |
| 97 | } |
| 98 | } |
| 99 | found = 1; |
| 100 | break; |
| 101 | } |
| 102 | if (found) { |
| 103 | DBG("Found event %s for channel %s", name, |
| 104 | channel->channel->name); |
| 105 | return ev; |
| 106 | } else { |
| 107 | return NULL; |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | /* |
| 112 | * Find the event name for the given channel. |
| 113 | */ |
| 114 | struct ltt_kernel_event *trace_kernel_get_event_by_name( |
| 115 | char *name, struct ltt_kernel_channel *channel, |
| 116 | enum lttng_event_type type) |
| 117 | { |
| 118 | struct ltt_kernel_event *ev; |
| 119 | int found = 0; |
| 120 | |
| 121 | assert(name); |
| 122 | assert(channel); |
| 123 | |
| 124 | cds_list_for_each_entry(ev, &channel->events_list.head, list) { |
| 125 | if (type != LTTNG_EVENT_ALL && ev->type != type) { |
| 126 | continue; |
| 127 | } |
| 128 | if (strcmp(name, ev->event->name)) { |
| 129 | continue; |
| 130 | } |
| 131 | found = 1; |
| 132 | break; |
| 133 | } |
| 134 | if (found) { |
| 135 | DBG("Found event %s for channel %s", name, |
| 136 | channel->channel->name); |
| 137 | return ev; |
| 138 | } else { |
| 139 | return NULL; |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | /* |
| 144 | * Allocate and initialize a kernel session data structure. |
| 145 | * |
| 146 | * Return pointer to structure or NULL. |
| 147 | */ |
| 148 | struct ltt_kernel_session *trace_kernel_create_session(void) |
| 149 | { |
| 150 | struct ltt_kernel_session *lks = NULL; |
| 151 | |
| 152 | /* Allocate a new ltt kernel session */ |
| 153 | lks = zmalloc(sizeof(struct ltt_kernel_session)); |
| 154 | if (lks == NULL) { |
| 155 | PERROR("create kernel session zmalloc"); |
| 156 | goto alloc_error; |
| 157 | } |
| 158 | |
| 159 | /* Init data structure */ |
| 160 | lks->fd = -1; |
| 161 | lks->metadata_stream_fd = -1; |
| 162 | lks->channel_count = 0; |
| 163 | lks->stream_count_global = 0; |
| 164 | lks->metadata = NULL; |
| 165 | CDS_INIT_LIST_HEAD(&lks->channel_list.head); |
| 166 | |
| 167 | lks->tracker_pid = process_attr_tracker_create(); |
| 168 | if (!lks->tracker_pid) { |
| 169 | goto error; |
| 170 | } |
| 171 | lks->tracker_vpid = process_attr_tracker_create(); |
| 172 | if (!lks->tracker_vpid) { |
| 173 | goto error; |
| 174 | } |
| 175 | lks->tracker_uid = process_attr_tracker_create(); |
| 176 | if (!lks->tracker_uid) { |
| 177 | goto error; |
| 178 | } |
| 179 | lks->tracker_vuid = process_attr_tracker_create(); |
| 180 | if (!lks->tracker_vuid) { |
| 181 | goto error; |
| 182 | } |
| 183 | lks->tracker_gid = process_attr_tracker_create(); |
| 184 | if (!lks->tracker_gid) { |
| 185 | goto error; |
| 186 | } |
| 187 | lks->tracker_vgid = process_attr_tracker_create(); |
| 188 | if (!lks->tracker_vgid) { |
| 189 | goto error; |
| 190 | } |
| 191 | lks->consumer = consumer_create_output(CONSUMER_DST_LOCAL); |
| 192 | if (lks->consumer == NULL) { |
| 193 | goto error; |
| 194 | } |
| 195 | |
| 196 | return lks; |
| 197 | |
| 198 | error: |
| 199 | process_attr_tracker_destroy(lks->tracker_pid); |
| 200 | process_attr_tracker_destroy(lks->tracker_vpid); |
| 201 | process_attr_tracker_destroy(lks->tracker_uid); |
| 202 | process_attr_tracker_destroy(lks->tracker_vuid); |
| 203 | process_attr_tracker_destroy(lks->tracker_gid); |
| 204 | process_attr_tracker_destroy(lks->tracker_vgid); |
| 205 | free(lks); |
| 206 | |
| 207 | alloc_error: |
| 208 | return NULL; |
| 209 | } |
| 210 | |
| 211 | /* |
| 212 | * Allocate and initialize a kernel channel data structure. |
| 213 | * |
| 214 | * Return pointer to structure or NULL. |
| 215 | */ |
| 216 | struct ltt_kernel_channel *trace_kernel_create_channel( |
| 217 | struct lttng_channel *chan) |
| 218 | { |
| 219 | struct ltt_kernel_channel *lkc; |
| 220 | struct lttng_channel_extended *extended = NULL; |
| 221 | |
| 222 | assert(chan); |
| 223 | |
| 224 | lkc = zmalloc(sizeof(struct ltt_kernel_channel)); |
| 225 | if (lkc == NULL) { |
| 226 | PERROR("ltt_kernel_channel zmalloc"); |
| 227 | goto error; |
| 228 | } |
| 229 | |
| 230 | lkc->channel = zmalloc(sizeof(struct lttng_channel)); |
| 231 | if (lkc->channel == NULL) { |
| 232 | PERROR("lttng_channel zmalloc"); |
| 233 | goto error; |
| 234 | } |
| 235 | |
| 236 | extended = zmalloc(sizeof(struct lttng_channel_extended)); |
| 237 | if (!extended) { |
| 238 | PERROR("lttng_channel_channel zmalloc"); |
| 239 | goto error; |
| 240 | } |
| 241 | memcpy(lkc->channel, chan, sizeof(struct lttng_channel)); |
| 242 | memcpy(extended, chan->attr.extended.ptr, sizeof(struct lttng_channel_extended)); |
| 243 | lkc->channel->attr.extended.ptr = extended; |
| 244 | extended = NULL; |
| 245 | |
| 246 | /* |
| 247 | * If we receive an empty string for channel name, it means the |
| 248 | * default channel name is requested. |
| 249 | */ |
| 250 | if (chan->name[0] == '\0') { |
| 251 | strncpy(lkc->channel->name, DEFAULT_CHANNEL_NAME, |
| 252 | sizeof(lkc->channel->name)); |
| 253 | } |
| 254 | lkc->channel->name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 255 | |
| 256 | lkc->fd = -1; |
| 257 | lkc->stream_count = 0; |
| 258 | lkc->event_count = 0; |
| 259 | lkc->enabled = 1; |
| 260 | lkc->published_to_notification_thread = false; |
| 261 | /* Init linked list */ |
| 262 | CDS_INIT_LIST_HEAD(&lkc->events_list.head); |
| 263 | CDS_INIT_LIST_HEAD(&lkc->stream_list.head); |
| 264 | CDS_INIT_LIST_HEAD(&lkc->ctx_list); |
| 265 | |
| 266 | return lkc; |
| 267 | |
| 268 | error: |
| 269 | if (lkc) { |
| 270 | free(lkc->channel); |
| 271 | } |
| 272 | free(extended); |
| 273 | free(lkc); |
| 274 | return NULL; |
| 275 | } |
| 276 | |
| 277 | /* |
| 278 | * Allocate and init a kernel context object. |
| 279 | * |
| 280 | * Return the allocated object or NULL on error. |
| 281 | */ |
| 282 | struct ltt_kernel_context *trace_kernel_create_context( |
| 283 | struct lttng_kernel_abi_context *ctx) |
| 284 | { |
| 285 | struct ltt_kernel_context *kctx; |
| 286 | |
| 287 | kctx = zmalloc(sizeof(*kctx)); |
| 288 | if (!kctx) { |
| 289 | PERROR("zmalloc kernel context"); |
| 290 | goto error; |
| 291 | } |
| 292 | |
| 293 | if (ctx) { |
| 294 | memcpy(&kctx->ctx, ctx, sizeof(kctx->ctx)); |
| 295 | } |
| 296 | error: |
| 297 | return kctx; |
| 298 | } |
| 299 | |
| 300 | /* |
| 301 | * Allocate and init a kernel context object from an existing kernel context |
| 302 | * object. |
| 303 | * |
| 304 | * Return the allocated object or NULL on error. |
| 305 | */ |
| 306 | struct ltt_kernel_context *trace_kernel_copy_context( |
| 307 | struct ltt_kernel_context *kctx) |
| 308 | { |
| 309 | struct ltt_kernel_context *kctx_copy; |
| 310 | |
| 311 | assert(kctx); |
| 312 | kctx_copy = zmalloc(sizeof(*kctx_copy)); |
| 313 | if (!kctx_copy) { |
| 314 | PERROR("zmalloc ltt_kernel_context"); |
| 315 | goto error; |
| 316 | } |
| 317 | |
| 318 | memcpy(kctx_copy, kctx, sizeof(*kctx_copy)); |
| 319 | memset(&kctx_copy->list, 0, sizeof(kctx_copy->list)); |
| 320 | |
| 321 | error: |
| 322 | return kctx_copy; |
| 323 | } |
| 324 | |
| 325 | /* |
| 326 | * Allocate and initialize a kernel event. Set name and event type. |
| 327 | * We own filter_expression, and filter. |
| 328 | * |
| 329 | * Return pointer to structure or NULL. |
| 330 | */ |
| 331 | enum lttng_error_code trace_kernel_create_event( |
| 332 | struct lttng_event *ev, char *filter_expression, |
| 333 | struct lttng_bytecode *filter, |
| 334 | struct ltt_kernel_event **kernel_event) |
| 335 | { |
| 336 | enum lttng_error_code ret; |
| 337 | struct lttng_kernel_abi_event *attr; |
| 338 | struct ltt_kernel_event *local_kernel_event; |
| 339 | struct lttng_userspace_probe_location *userspace_probe_location = NULL; |
| 340 | |
| 341 | assert(ev); |
| 342 | |
| 343 | local_kernel_event = zmalloc(sizeof(struct ltt_kernel_event)); |
| 344 | attr = zmalloc(sizeof(struct lttng_kernel_abi_event)); |
| 345 | if (local_kernel_event == NULL || attr == NULL) { |
| 346 | PERROR("kernel event zmalloc"); |
| 347 | ret = LTTNG_ERR_NOMEM; |
| 348 | goto error; |
| 349 | } |
| 350 | |
| 351 | switch (ev->type) { |
| 352 | case LTTNG_EVENT_PROBE: |
| 353 | attr->instrumentation = LTTNG_KERNEL_ABI_KPROBE; |
| 354 | attr->u.kprobe.addr = ev->attr.probe.addr; |
| 355 | attr->u.kprobe.offset = ev->attr.probe.offset; |
| 356 | strncpy(attr->u.kprobe.symbol_name, |
| 357 | ev->attr.probe.symbol_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 358 | attr->u.kprobe.symbol_name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 359 | break; |
| 360 | case LTTNG_EVENT_USERSPACE_PROBE: |
| 361 | { |
| 362 | const struct lttng_userspace_probe_location* location = NULL; |
| 363 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
| 364 | |
| 365 | location = lttng_event_get_userspace_probe_location(ev); |
| 366 | if (!location) { |
| 367 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; |
| 368 | goto error; |
| 369 | } |
| 370 | |
| 371 | /* |
| 372 | * From this point on, the specific term 'uprobe' is used |
| 373 | * instead of the generic 'userspace probe' because it's the |
| 374 | * technology used at the moment for this instrumentation. |
| 375 | * LTTng currently implements userspace probes using uprobes. |
| 376 | * In the interactions with the kernel tracer, we use the |
| 377 | * uprobe term. |
| 378 | */ |
| 379 | attr->instrumentation = LTTNG_KERNEL_ABI_UPROBE; |
| 380 | |
| 381 | lookup = lttng_userspace_probe_location_get_lookup_method( |
| 382 | location); |
| 383 | if (!lookup) { |
| 384 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; |
| 385 | goto error; |
| 386 | } |
| 387 | |
| 388 | /* |
| 389 | * From the kernel tracer's perspective, all userspace probe |
| 390 | * event types are all the same: a file and an offset. |
| 391 | */ |
| 392 | switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) { |
| 393 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: |
| 394 | /* Get the file descriptor on the target binary. */ |
| 395 | attr->u.uprobe.fd = |
| 396 | lttng_userspace_probe_location_function_get_binary_fd(location); |
| 397 | |
| 398 | /* |
| 399 | * Save a reference to the probe location used during |
| 400 | * the listing of events. |
| 401 | */ |
| 402 | userspace_probe_location = |
| 403 | lttng_userspace_probe_location_copy(location); |
| 404 | break; |
| 405 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: |
| 406 | /* Get the file descriptor on the target binary. */ |
| 407 | attr->u.uprobe.fd = |
| 408 | lttng_userspace_probe_location_tracepoint_get_binary_fd(location); |
| 409 | |
| 410 | /* |
| 411 | * Save a reference to the probe location used during the listing of |
| 412 | * events. |
| 413 | */ |
| 414 | userspace_probe_location = |
| 415 | lttng_userspace_probe_location_copy(location); |
| 416 | break; |
| 417 | default: |
| 418 | DBG("Unsupported lookup method type"); |
| 419 | ret = LTTNG_ERR_PROBE_LOCATION_INVAL; |
| 420 | goto error; |
| 421 | } |
| 422 | break; |
| 423 | } |
| 424 | case LTTNG_EVENT_FUNCTION: |
| 425 | attr->instrumentation = LTTNG_KERNEL_ABI_KRETPROBE; |
| 426 | attr->u.kretprobe.addr = ev->attr.probe.addr; |
| 427 | attr->u.kretprobe.offset = ev->attr.probe.offset; |
| 428 | strncpy(attr->u.kretprobe.symbol_name, |
| 429 | ev->attr.probe.symbol_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 430 | attr->u.kretprobe.symbol_name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 431 | break; |
| 432 | case LTTNG_EVENT_FUNCTION_ENTRY: |
| 433 | attr->instrumentation = LTTNG_KERNEL_ABI_FUNCTION; |
| 434 | strncpy(attr->u.ftrace.symbol_name, |
| 435 | ev->attr.ftrace.symbol_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 436 | attr->u.ftrace.symbol_name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 437 | break; |
| 438 | case LTTNG_EVENT_TRACEPOINT: |
| 439 | attr->instrumentation = LTTNG_KERNEL_ABI_TRACEPOINT; |
| 440 | break; |
| 441 | case LTTNG_EVENT_SYSCALL: |
| 442 | attr->instrumentation = LTTNG_KERNEL_ABI_SYSCALL; |
| 443 | attr->u.syscall.abi = LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL; |
| 444 | attr->u.syscall.entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT; |
| 445 | attr->u.syscall.match = LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME; |
| 446 | break; |
| 447 | case LTTNG_EVENT_ALL: |
| 448 | attr->instrumentation = LTTNG_KERNEL_ABI_ALL; |
| 449 | break; |
| 450 | default: |
| 451 | ERR("Unknown kernel instrumentation type (%d)", ev->type); |
| 452 | ret = LTTNG_ERR_INVALID; |
| 453 | goto error; |
| 454 | } |
| 455 | |
| 456 | /* Copy event name */ |
| 457 | strncpy(attr->name, ev->name, LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 458 | attr->name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 459 | |
| 460 | /* Setting up a kernel event */ |
| 461 | local_kernel_event->fd = -1; |
| 462 | local_kernel_event->event = attr; |
| 463 | local_kernel_event->enabled = 1; |
| 464 | local_kernel_event->filter_expression = filter_expression; |
| 465 | local_kernel_event->filter = filter; |
| 466 | local_kernel_event->userspace_probe_location = userspace_probe_location; |
| 467 | |
| 468 | *kernel_event = local_kernel_event; |
| 469 | |
| 470 | return LTTNG_OK; |
| 471 | |
| 472 | error: |
| 473 | free(filter_expression); |
| 474 | free(filter); |
| 475 | free(local_kernel_event); |
| 476 | free(attr); |
| 477 | return ret; |
| 478 | } |
| 479 | |
| 480 | /* |
| 481 | * Allocate and initialize a kernel token event rule. |
| 482 | * |
| 483 | * Return pointer to structure or NULL. |
| 484 | */ |
| 485 | enum lttng_error_code trace_kernel_create_event_notifier_rule( |
| 486 | struct lttng_trigger *trigger, |
| 487 | uint64_t token, |
| 488 | uint64_t error_counter_index, |
| 489 | struct ltt_kernel_event_notifier_rule **event_notifier_rule) |
| 490 | { |
| 491 | enum lttng_error_code ret = LTTNG_OK; |
| 492 | enum lttng_condition_type condition_type; |
| 493 | enum lttng_event_rule_type event_rule_type; |
| 494 | enum lttng_condition_status condition_status; |
| 495 | struct ltt_kernel_event_notifier_rule *local_kernel_token_event_rule; |
| 496 | const struct lttng_condition *condition = NULL; |
| 497 | const struct lttng_event_rule *event_rule = NULL; |
| 498 | |
| 499 | assert(event_notifier_rule); |
| 500 | |
| 501 | condition = lttng_trigger_get_const_condition(trigger); |
| 502 | assert(condition); |
| 503 | |
| 504 | condition_type = lttng_condition_get_type(condition); |
| 505 | assert(condition_type == LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES); |
| 506 | |
| 507 | condition_status = lttng_condition_event_rule_matches_get_rule( |
| 508 | condition, &event_rule); |
| 509 | assert(condition_status == LTTNG_CONDITION_STATUS_OK); |
| 510 | assert(event_rule); |
| 511 | |
| 512 | event_rule_type = lttng_event_rule_get_type(event_rule); |
| 513 | assert(event_rule_type != LTTNG_EVENT_RULE_TYPE_UNKNOWN); |
| 514 | |
| 515 | local_kernel_token_event_rule = |
| 516 | zmalloc(sizeof(struct ltt_kernel_event_notifier_rule)); |
| 517 | if (local_kernel_token_event_rule == NULL) { |
| 518 | PERROR("Failed to allocate ltt_kernel_token_event_rule structure"); |
| 519 | ret = LTTNG_ERR_NOMEM; |
| 520 | goto error; |
| 521 | } |
| 522 | |
| 523 | local_kernel_token_event_rule->fd = -1; |
| 524 | local_kernel_token_event_rule->enabled = 1; |
| 525 | local_kernel_token_event_rule->token = token; |
| 526 | local_kernel_token_event_rule->error_counter_index = error_counter_index; |
| 527 | |
| 528 | /* Get the reference of the event rule. */ |
| 529 | lttng_trigger_get(trigger); |
| 530 | |
| 531 | local_kernel_token_event_rule->trigger = trigger; |
| 532 | /* The event rule still owns the filter and bytecode. */ |
| 533 | local_kernel_token_event_rule->filter = |
| 534 | lttng_event_rule_get_filter_bytecode(event_rule); |
| 535 | |
| 536 | DBG3("Created kernel event notifier rule: token = %" PRIu64, |
| 537 | local_kernel_token_event_rule->token); |
| 538 | error: |
| 539 | *event_notifier_rule = local_kernel_token_event_rule; |
| 540 | return ret; |
| 541 | } |
| 542 | |
| 543 | /* |
| 544 | * Initialize a kernel trigger from an event rule. |
| 545 | */ |
| 546 | enum lttng_error_code trace_kernel_init_event_notifier_from_event_rule( |
| 547 | const struct lttng_event_rule *rule, |
| 548 | struct lttng_kernel_abi_event_notifier *kernel_event_notifier) |
| 549 | { |
| 550 | enum lttng_error_code ret_code; |
| 551 | const char *name; |
| 552 | int strncpy_ret; |
| 553 | |
| 554 | switch (lttng_event_rule_get_type(rule)) { |
| 555 | case LTTNG_EVENT_RULE_TYPE_KERNEL_PROBE: |
| 556 | { |
| 557 | uint64_t address = 0, offset = 0; |
| 558 | const char *symbol_name = NULL; |
| 559 | const struct lttng_kernel_probe_location *location = NULL; |
| 560 | enum lttng_kernel_probe_location_status k_status; |
| 561 | enum lttng_event_rule_status status; |
| 562 | |
| 563 | status = lttng_event_rule_kernel_probe_get_location(rule, &location); |
| 564 | if (status != LTTNG_EVENT_RULE_STATUS_OK) { |
| 565 | ret_code = LTTNG_ERR_PROBE_LOCATION_INVAL; |
| 566 | goto error; |
| 567 | } |
| 568 | |
| 569 | switch (lttng_kernel_probe_location_get_type(location)) { |
| 570 | case LTTNG_KERNEL_PROBE_LOCATION_TYPE_ADDRESS: |
| 571 | { |
| 572 | k_status = lttng_kernel_probe_location_address_get_address( |
| 573 | location, &address); |
| 574 | assert(k_status == LTTNG_KERNEL_PROBE_LOCATION_STATUS_OK); |
| 575 | break; |
| 576 | } |
| 577 | case LTTNG_KERNEL_PROBE_LOCATION_TYPE_SYMBOL_OFFSET: |
| 578 | { |
| 579 | k_status = lttng_kernel_probe_location_symbol_get_offset( |
| 580 | location, &offset); |
| 581 | assert(k_status == LTTNG_KERNEL_PROBE_LOCATION_STATUS_OK); |
| 582 | symbol_name = lttng_kernel_probe_location_symbol_get_name( |
| 583 | location); |
| 584 | break; |
| 585 | } |
| 586 | default: |
| 587 | abort(); |
| 588 | } |
| 589 | |
| 590 | kernel_event_notifier->event.instrumentation = LTTNG_KERNEL_ABI_KPROBE; |
| 591 | kernel_event_notifier->event.u.kprobe.addr = address; |
| 592 | kernel_event_notifier->event.u.kprobe.offset = offset; |
| 593 | if (symbol_name) { |
| 594 | strncpy_ret = lttng_strncpy( |
| 595 | kernel_event_notifier->event.u.kprobe.symbol_name, |
| 596 | symbol_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 597 | |
| 598 | if (strncpy_ret) { |
| 599 | ret_code = LTTNG_ERR_INVALID; |
| 600 | goto error; |
| 601 | } |
| 602 | } |
| 603 | |
| 604 | kernel_event_notifier->event.u.kprobe.symbol_name[LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 605 | |
| 606 | status = lttng_event_rule_kernel_probe_get_event_name(rule, &name); |
| 607 | assert(status == LTTNG_EVENT_RULE_STATUS_OK); |
| 608 | ret_code = LTTNG_OK; |
| 609 | break; |
| 610 | } |
| 611 | case LTTNG_EVENT_RULE_TYPE_USERSPACE_PROBE: |
| 612 | { |
| 613 | const struct lttng_userspace_probe_location* location = NULL; |
| 614 | const struct lttng_userspace_probe_location_lookup_method *lookup = NULL; |
| 615 | enum lttng_event_rule_status status; |
| 616 | |
| 617 | status = lttng_event_rule_userspace_probe_get_location(rule, &location); |
| 618 | if (status != LTTNG_EVENT_RULE_STATUS_OK) { |
| 619 | ret_code = LTTNG_ERR_PROBE_LOCATION_INVAL; |
| 620 | goto error; |
| 621 | } |
| 622 | |
| 623 | kernel_event_notifier->event.instrumentation = LTTNG_KERNEL_ABI_UPROBE; |
| 624 | |
| 625 | lookup = lttng_userspace_probe_location_get_lookup_method( |
| 626 | location); |
| 627 | if (!lookup) { |
| 628 | ret_code = LTTNG_ERR_PROBE_LOCATION_INVAL; |
| 629 | goto error; |
| 630 | } |
| 631 | |
| 632 | /* |
| 633 | * From the kernel tracer's perspective, all userspace probe |
| 634 | * event types are all the same: a file and an offset. |
| 635 | */ |
| 636 | switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) { |
| 637 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF: |
| 638 | /* Get the file descriptor on the target binary. */ |
| 639 | kernel_event_notifier->event.u.uprobe.fd = |
| 640 | lttng_userspace_probe_location_function_get_binary_fd(location); |
| 641 | |
| 642 | break; |
| 643 | case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT: |
| 644 | /* Get the file descriptor on the target binary. */ |
| 645 | kernel_event_notifier->event.u.uprobe.fd = |
| 646 | lttng_userspace_probe_location_tracepoint_get_binary_fd(location); |
| 647 | break; |
| 648 | default: |
| 649 | abort(); |
| 650 | } |
| 651 | |
| 652 | status = lttng_event_rule_userspace_probe_get_event_name( |
| 653 | rule, &name); |
| 654 | assert(status == LTTNG_EVENT_RULE_STATUS_OK); |
| 655 | ret_code = LTTNG_OK; |
| 656 | break; |
| 657 | } |
| 658 | case LTTNG_EVENT_RULE_TYPE_TRACEPOINT: |
| 659 | { |
| 660 | const enum lttng_domain_type domain = |
| 661 | lttng_event_rule_get_domain_type(rule); |
| 662 | const enum lttng_event_rule_status status = |
| 663 | lttng_event_rule_tracepoint_get_name_pattern( |
| 664 | rule, &name); |
| 665 | |
| 666 | assert(domain == LTTNG_DOMAIN_KERNEL); |
| 667 | assert(status == LTTNG_EVENT_RULE_STATUS_OK); |
| 668 | kernel_event_notifier->event.instrumentation = |
| 669 | LTTNG_KERNEL_ABI_TRACEPOINT; |
| 670 | |
| 671 | ret_code = LTTNG_OK; |
| 672 | break; |
| 673 | } |
| 674 | case LTTNG_EVENT_RULE_TYPE_KERNEL_SYSCALL: |
| 675 | { |
| 676 | const enum lttng_event_rule_status status = |
| 677 | lttng_event_rule_kernel_syscall_get_name_pattern( |
| 678 | rule, &name); |
| 679 | const enum lttng_event_rule_kernel_syscall_emission_site |
| 680 | emission_site = |
| 681 | lttng_event_rule_kernel_syscall_get_emission_site(rule); |
| 682 | enum lttng_kernel_abi_syscall_entryexit entryexit; |
| 683 | |
| 684 | assert(status == LTTNG_EVENT_RULE_STATUS_OK); |
| 685 | assert(emission_site != LTTNG_EVENT_RULE_KERNEL_SYSCALL_EMISSION_SITE_UNKNOWN); |
| 686 | |
| 687 | switch(emission_site) { |
| 688 | case LTTNG_EVENT_RULE_KERNEL_SYSCALL_EMISSION_SITE_ENTRY: |
| 689 | entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRY; |
| 690 | break; |
| 691 | case LTTNG_EVENT_RULE_KERNEL_SYSCALL_EMISSION_SITE_EXIT: |
| 692 | entryexit = LTTNG_KERNEL_ABI_SYSCALL_EXIT; |
| 693 | break; |
| 694 | case LTTNG_EVENT_RULE_KERNEL_SYSCALL_EMISSION_SITE_ENTRY_EXIT: |
| 695 | entryexit = LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT; |
| 696 | break; |
| 697 | default: |
| 698 | abort(); |
| 699 | break; |
| 700 | } |
| 701 | |
| 702 | kernel_event_notifier->event.instrumentation = |
| 703 | LTTNG_KERNEL_ABI_SYSCALL; |
| 704 | kernel_event_notifier->event.u.syscall.abi = |
| 705 | LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL; |
| 706 | kernel_event_notifier->event.u.syscall.entryexit = |
| 707 | entryexit; |
| 708 | kernel_event_notifier->event.u.syscall.match = |
| 709 | LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME; |
| 710 | ret_code = LTTNG_OK; |
| 711 | break; |
| 712 | } |
| 713 | case LTTNG_EVENT_RULE_TYPE_KERNEL_FUNCTION: |
| 714 | default: |
| 715 | abort(); |
| 716 | break; |
| 717 | } |
| 718 | |
| 719 | strncpy_ret = lttng_strncpy(kernel_event_notifier->event.name, name, |
| 720 | LTTNG_KERNEL_ABI_SYM_NAME_LEN); |
| 721 | if (strncpy_ret) { |
| 722 | ret_code = LTTNG_ERR_INVALID; |
| 723 | goto error; |
| 724 | } |
| 725 | |
| 726 | error: |
| 727 | return ret_code; |
| 728 | } |
| 729 | /* |
| 730 | * Allocate and initialize a kernel metadata. |
| 731 | * |
| 732 | * Return pointer to structure or NULL. |
| 733 | */ |
| 734 | struct ltt_kernel_metadata *trace_kernel_create_metadata(void) |
| 735 | { |
| 736 | int ret; |
| 737 | struct ltt_kernel_metadata *lkm; |
| 738 | struct lttng_channel *chan; |
| 739 | |
| 740 | lkm = zmalloc(sizeof(struct ltt_kernel_metadata)); |
| 741 | chan = zmalloc(sizeof(struct lttng_channel)); |
| 742 | if (lkm == NULL || chan == NULL) { |
| 743 | PERROR("kernel metadata zmalloc"); |
| 744 | goto error; |
| 745 | } |
| 746 | |
| 747 | ret = lttng_strncpy( |
| 748 | chan->name, DEFAULT_METADATA_NAME, sizeof(chan->name)); |
| 749 | if (ret) { |
| 750 | ERR("Failed to initialize metadata channel name to `%s`", |
| 751 | DEFAULT_METADATA_NAME); |
| 752 | goto error; |
| 753 | } |
| 754 | |
| 755 | /* Set default attributes */ |
| 756 | chan->attr.overwrite = DEFAULT_METADATA_OVERWRITE; |
| 757 | chan->attr.subbuf_size = default_get_metadata_subbuf_size(); |
| 758 | chan->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM; |
| 759 | chan->attr.switch_timer_interval = DEFAULT_METADATA_SWITCH_TIMER; |
| 760 | chan->attr.read_timer_interval = DEFAULT_METADATA_READ_TIMER;; |
| 761 | |
| 762 | |
| 763 | /* |
| 764 | * The metadata channel of kernel sessions must use the "mmap" |
| 765 | * back-end since the consumer daemon accumulates complete |
| 766 | * metadata units before sending them to the relay daemon in |
| 767 | * live mode. The consumer daemon also needs to extract the contents |
| 768 | * of the metadata cache when computing a rotation position. |
| 769 | * |
| 770 | * In both cases, it is not possible to rely on the splice |
| 771 | * back-end as the consumer daemon may need to accumulate more |
| 772 | * content than can be backed by the ring buffer's underlying |
| 773 | * pages. |
| 774 | */ |
| 775 | chan->attr.output = LTTNG_EVENT_MMAP; |
| 776 | chan->attr.tracefile_size = 0; |
| 777 | chan->attr.tracefile_count = 0; |
| 778 | chan->attr.live_timer_interval = 0; |
| 779 | |
| 780 | /* Init metadata */ |
| 781 | lkm->fd = -1; |
| 782 | lkm->conf = chan; |
| 783 | |
| 784 | return lkm; |
| 785 | |
| 786 | error: |
| 787 | free(lkm); |
| 788 | free(chan); |
| 789 | return NULL; |
| 790 | } |
| 791 | |
| 792 | /* |
| 793 | * Allocate and initialize a kernel stream. The stream is set to ACTIVE_FD by |
| 794 | * default. |
| 795 | * |
| 796 | * Return pointer to structure or NULL. |
| 797 | */ |
| 798 | struct ltt_kernel_stream *trace_kernel_create_stream(const char *name, |
| 799 | unsigned int count) |
| 800 | { |
| 801 | int ret; |
| 802 | struct ltt_kernel_stream *lks; |
| 803 | |
| 804 | assert(name); |
| 805 | |
| 806 | lks = zmalloc(sizeof(struct ltt_kernel_stream)); |
| 807 | if (lks == NULL) { |
| 808 | PERROR("kernel stream zmalloc"); |
| 809 | goto error; |
| 810 | } |
| 811 | |
| 812 | /* Set name */ |
| 813 | ret = snprintf(lks->name, sizeof(lks->name), "%s_%u", name, count); |
| 814 | if (ret < 0) { |
| 815 | PERROR("snprintf stream name"); |
| 816 | goto error; |
| 817 | } |
| 818 | lks->name[sizeof(lks->name) - 1] = '\0'; |
| 819 | |
| 820 | /* Init stream */ |
| 821 | lks->fd = -1; |
| 822 | lks->state = 0; |
| 823 | lks->cpu = count; |
| 824 | |
| 825 | return lks; |
| 826 | |
| 827 | error: |
| 828 | return NULL; |
| 829 | } |
| 830 | |
| 831 | /* |
| 832 | * Cleanup kernel stream structure. |
| 833 | */ |
| 834 | void trace_kernel_destroy_stream(struct ltt_kernel_stream *stream) |
| 835 | { |
| 836 | assert(stream); |
| 837 | |
| 838 | DBG("[trace] Closing stream fd %d", stream->fd); |
| 839 | /* Close kernel fd */ |
| 840 | if (stream->fd >= 0) { |
| 841 | int ret; |
| 842 | |
| 843 | ret = close(stream->fd); |
| 844 | if (ret) { |
| 845 | PERROR("close"); |
| 846 | } |
| 847 | } |
| 848 | /* Remove from stream list */ |
| 849 | cds_list_del(&stream->list); |
| 850 | |
| 851 | free(stream); |
| 852 | } |
| 853 | |
| 854 | /* |
| 855 | * Cleanup kernel event structure. |
| 856 | */ |
| 857 | void trace_kernel_destroy_event(struct ltt_kernel_event *event) |
| 858 | { |
| 859 | assert(event); |
| 860 | |
| 861 | if (event->fd >= 0) { |
| 862 | int ret; |
| 863 | |
| 864 | DBG("[trace] Closing event fd %d", event->fd); |
| 865 | /* Close kernel fd */ |
| 866 | ret = close(event->fd); |
| 867 | if (ret) { |
| 868 | PERROR("close"); |
| 869 | } |
| 870 | } else { |
| 871 | DBG("[trace] Tearing down event (no associated file descriptor)"); |
| 872 | } |
| 873 | |
| 874 | /* Remove from event list */ |
| 875 | cds_list_del(&event->list); |
| 876 | |
| 877 | free(event->filter_expression); |
| 878 | free(event->filter); |
| 879 | |
| 880 | free(event->event); |
| 881 | free(event); |
| 882 | } |
| 883 | |
| 884 | /* |
| 885 | * Cleanup kernel event structure. |
| 886 | */ |
| 887 | static void free_token_event_rule_rcu(struct rcu_head *rcu_node) |
| 888 | { |
| 889 | struct ltt_kernel_event_notifier_rule *rule = caa_container_of(rcu_node, |
| 890 | struct ltt_kernel_event_notifier_rule, rcu_node); |
| 891 | |
| 892 | free(rule); |
| 893 | } |
| 894 | |
| 895 | void trace_kernel_destroy_event_notifier_rule( |
| 896 | struct ltt_kernel_event_notifier_rule *event) |
| 897 | { |
| 898 | assert(event); |
| 899 | |
| 900 | if (event->fd >= 0) { |
| 901 | const int ret = close(event->fd); |
| 902 | |
| 903 | DBG("Closing kernel event notifier rule file descriptor: fd = %d", |
| 904 | event->fd); |
| 905 | if (ret) { |
| 906 | PERROR("Failed to close kernel event notifier file descriptor: fd = %d", |
| 907 | event->fd); |
| 908 | } |
| 909 | } else { |
| 910 | DBG("Destroying kernel event notifier rule (no associated file descriptor)"); |
| 911 | } |
| 912 | |
| 913 | lttng_trigger_put(event->trigger); |
| 914 | call_rcu(&event->rcu_node, free_token_event_rule_rcu); |
| 915 | } |
| 916 | /* |
| 917 | * Cleanup kernel context structure. |
| 918 | */ |
| 919 | void trace_kernel_destroy_context(struct ltt_kernel_context *ctx) |
| 920 | { |
| 921 | assert(ctx); |
| 922 | |
| 923 | if (ctx->in_list) { |
| 924 | cds_list_del(&ctx->list); |
| 925 | } |
| 926 | free(ctx); |
| 927 | } |
| 928 | |
| 929 | /* |
| 930 | * Cleanup kernel channel structure. |
| 931 | */ |
| 932 | void trace_kernel_destroy_channel(struct ltt_kernel_channel *channel) |
| 933 | { |
| 934 | struct ltt_kernel_stream *stream, *stmp; |
| 935 | struct ltt_kernel_event *event, *etmp; |
| 936 | struct ltt_kernel_context *ctx, *ctmp; |
| 937 | int ret; |
| 938 | enum lttng_error_code status; |
| 939 | |
| 940 | assert(channel); |
| 941 | |
| 942 | DBG("[trace] Closing channel fd %d", channel->fd); |
| 943 | /* Close kernel fd */ |
| 944 | if (channel->fd >= 0) { |
| 945 | ret = close(channel->fd); |
| 946 | if (ret) { |
| 947 | PERROR("close"); |
| 948 | } |
| 949 | } |
| 950 | |
| 951 | /* For each stream in the channel list */ |
| 952 | cds_list_for_each_entry_safe(stream, stmp, &channel->stream_list.head, list) { |
| 953 | trace_kernel_destroy_stream(stream); |
| 954 | } |
| 955 | |
| 956 | /* For each event in the channel list */ |
| 957 | cds_list_for_each_entry_safe(event, etmp, &channel->events_list.head, list) { |
| 958 | trace_kernel_destroy_event(event); |
| 959 | } |
| 960 | |
| 961 | /* For each context in the channel list */ |
| 962 | cds_list_for_each_entry_safe(ctx, ctmp, &channel->ctx_list, list) { |
| 963 | trace_kernel_destroy_context(ctx); |
| 964 | } |
| 965 | |
| 966 | /* Remove from channel list */ |
| 967 | cds_list_del(&channel->list); |
| 968 | |
| 969 | if (the_notification_thread_handle && |
| 970 | channel->published_to_notification_thread) { |
| 971 | status = notification_thread_command_remove_channel( |
| 972 | the_notification_thread_handle, channel->key, |
| 973 | LTTNG_DOMAIN_KERNEL); |
| 974 | assert(status == LTTNG_OK); |
| 975 | } |
| 976 | free(channel->channel->attr.extended.ptr); |
| 977 | free(channel->channel); |
| 978 | free(channel); |
| 979 | } |
| 980 | |
| 981 | /* |
| 982 | * Cleanup kernel metadata structure. |
| 983 | */ |
| 984 | void trace_kernel_destroy_metadata(struct ltt_kernel_metadata *metadata) |
| 985 | { |
| 986 | assert(metadata); |
| 987 | |
| 988 | DBG("[trace] Closing metadata fd %d", metadata->fd); |
| 989 | /* Close kernel fd */ |
| 990 | if (metadata->fd >= 0) { |
| 991 | int ret; |
| 992 | |
| 993 | ret = close(metadata->fd); |
| 994 | if (ret) { |
| 995 | PERROR("close"); |
| 996 | } |
| 997 | } |
| 998 | |
| 999 | free(metadata->conf); |
| 1000 | free(metadata); |
| 1001 | } |
| 1002 | |
| 1003 | /* |
| 1004 | * Cleanup kernel session structure |
| 1005 | * |
| 1006 | * Should *NOT* be called with RCU read-side lock held. |
| 1007 | */ |
| 1008 | void trace_kernel_destroy_session(struct ltt_kernel_session *session) |
| 1009 | { |
| 1010 | struct ltt_kernel_channel *channel, *ctmp; |
| 1011 | int ret; |
| 1012 | |
| 1013 | assert(session); |
| 1014 | |
| 1015 | DBG("[trace] Closing session fd %d", session->fd); |
| 1016 | /* Close kernel fds */ |
| 1017 | if (session->fd >= 0) { |
| 1018 | ret = close(session->fd); |
| 1019 | if (ret) { |
| 1020 | PERROR("close"); |
| 1021 | } |
| 1022 | } |
| 1023 | |
| 1024 | if (session->metadata_stream_fd >= 0) { |
| 1025 | DBG("[trace] Closing metadata stream fd %d", session->metadata_stream_fd); |
| 1026 | ret = close(session->metadata_stream_fd); |
| 1027 | if (ret) { |
| 1028 | PERROR("close"); |
| 1029 | } |
| 1030 | } |
| 1031 | |
| 1032 | if (session->metadata != NULL) { |
| 1033 | trace_kernel_destroy_metadata(session->metadata); |
| 1034 | } |
| 1035 | |
| 1036 | cds_list_for_each_entry_safe(channel, ctmp, &session->channel_list.head, list) { |
| 1037 | trace_kernel_destroy_channel(channel); |
| 1038 | } |
| 1039 | } |
| 1040 | |
| 1041 | /* Free elements needed by destroy notifiers. */ |
| 1042 | void trace_kernel_free_session(struct ltt_kernel_session *session) |
| 1043 | { |
| 1044 | /* Wipe consumer output object */ |
| 1045 | consumer_output_put(session->consumer); |
| 1046 | |
| 1047 | process_attr_tracker_destroy(session->tracker_pid); |
| 1048 | process_attr_tracker_destroy(session->tracker_vpid); |
| 1049 | process_attr_tracker_destroy(session->tracker_uid); |
| 1050 | process_attr_tracker_destroy(session->tracker_vuid); |
| 1051 | process_attr_tracker_destroy(session->tracker_gid); |
| 1052 | process_attr_tracker_destroy(session->tracker_vgid); |
| 1053 | |
| 1054 | free(session); |
| 1055 | } |