| 1 | /* |
| 2 | * Copyright (C) 2011 EfficiOS Inc. |
| 3 | * Copyright (C) 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 4 | * |
| 5 | * SPDX-License-Identifier: GPL-2.0-only |
| 6 | * |
| 7 | */ |
| 8 | |
| 9 | #define _LGPL_SOURCE |
| 10 | #include <inttypes.h> |
| 11 | #include <string.h> |
| 12 | #include <unistd.h> |
| 13 | |
| 14 | #include <common/common.h> |
| 15 | #include <common/defaults.h> |
| 16 | #include <common/sessiond-comm/sessiond-comm.h> |
| 17 | |
| 18 | #include "channel.h" |
| 19 | #include "lttng-sessiond.h" |
| 20 | #include "kernel.h" |
| 21 | #include "lttng-ust-ctl.h" |
| 22 | #include "lttng-ust-error.h" |
| 23 | #include "utils.h" |
| 24 | #include "ust-app.h" |
| 25 | #include "agent.h" |
| 26 | |
| 27 | /* |
| 28 | * Return allocated channel attributes. |
| 29 | */ |
| 30 | struct lttng_channel *channel_new_default_attr(int dom, |
| 31 | enum lttng_buffer_type type) |
| 32 | { |
| 33 | struct lttng_channel *chan; |
| 34 | const char *channel_name = DEFAULT_CHANNEL_NAME; |
| 35 | struct lttng_channel_extended *extended_attr = NULL; |
| 36 | |
| 37 | chan = zmalloc(sizeof(struct lttng_channel)); |
| 38 | if (chan == NULL) { |
| 39 | PERROR("zmalloc channel init"); |
| 40 | goto error_alloc; |
| 41 | } |
| 42 | |
| 43 | extended_attr = zmalloc(sizeof(struct lttng_channel_extended)); |
| 44 | if (!extended_attr) { |
| 45 | PERROR("zmalloc channel extended init"); |
| 46 | goto error; |
| 47 | } |
| 48 | |
| 49 | chan->attr.extended.ptr = extended_attr; |
| 50 | |
| 51 | /* Same for all domains. */ |
| 52 | chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE; |
| 53 | chan->attr.tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE; |
| 54 | chan->attr.tracefile_count = DEFAULT_CHANNEL_TRACEFILE_COUNT; |
| 55 | |
| 56 | switch (dom) { |
| 57 | case LTTNG_DOMAIN_KERNEL: |
| 58 | assert(type == LTTNG_BUFFER_GLOBAL); |
| 59 | chan->attr.subbuf_size = |
| 60 | default_get_kernel_channel_subbuf_size(); |
| 61 | chan->attr.num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM; |
| 62 | chan->attr.output = DEFAULT_KERNEL_CHANNEL_OUTPUT; |
| 63 | chan->attr.switch_timer_interval = DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER; |
| 64 | chan->attr.read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER; |
| 65 | chan->attr.live_timer_interval = DEFAULT_KERNEL_CHANNEL_LIVE_TIMER; |
| 66 | extended_attr->blocking_timeout = DEFAULT_KERNEL_CHANNEL_BLOCKING_TIMEOUT; |
| 67 | extended_attr->monitor_timer_interval = |
| 68 | DEFAULT_KERNEL_CHANNEL_MONITOR_TIMER; |
| 69 | break; |
| 70 | case LTTNG_DOMAIN_JUL: |
| 71 | channel_name = DEFAULT_JUL_CHANNEL_NAME; |
| 72 | goto common_ust; |
| 73 | case LTTNG_DOMAIN_LOG4J: |
| 74 | channel_name = DEFAULT_LOG4J_CHANNEL_NAME; |
| 75 | goto common_ust; |
| 76 | case LTTNG_DOMAIN_PYTHON: |
| 77 | channel_name = DEFAULT_PYTHON_CHANNEL_NAME; |
| 78 | goto common_ust; |
| 79 | case LTTNG_DOMAIN_UST: |
| 80 | common_ust: |
| 81 | switch (type) { |
| 82 | case LTTNG_BUFFER_PER_UID: |
| 83 | chan->attr.subbuf_size = default_get_ust_uid_channel_subbuf_size(); |
| 84 | chan->attr.num_subbuf = DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM; |
| 85 | chan->attr.output = DEFAULT_UST_UID_CHANNEL_OUTPUT; |
| 86 | chan->attr.switch_timer_interval = |
| 87 | DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER; |
| 88 | chan->attr.read_timer_interval = |
| 89 | DEFAULT_UST_UID_CHANNEL_READ_TIMER; |
| 90 | chan->attr.live_timer_interval = |
| 91 | DEFAULT_UST_UID_CHANNEL_LIVE_TIMER; |
| 92 | extended_attr->blocking_timeout = DEFAULT_UST_UID_CHANNEL_BLOCKING_TIMEOUT; |
| 93 | extended_attr->monitor_timer_interval = |
| 94 | DEFAULT_UST_UID_CHANNEL_MONITOR_TIMER; |
| 95 | break; |
| 96 | case LTTNG_BUFFER_PER_PID: |
| 97 | default: |
| 98 | chan->attr.subbuf_size = default_get_ust_pid_channel_subbuf_size(); |
| 99 | chan->attr.num_subbuf = DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM; |
| 100 | chan->attr.output = DEFAULT_UST_PID_CHANNEL_OUTPUT; |
| 101 | chan->attr.switch_timer_interval = |
| 102 | DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER; |
| 103 | chan->attr.read_timer_interval = |
| 104 | DEFAULT_UST_PID_CHANNEL_READ_TIMER; |
| 105 | chan->attr.live_timer_interval = |
| 106 | DEFAULT_UST_PID_CHANNEL_LIVE_TIMER; |
| 107 | extended_attr->blocking_timeout = DEFAULT_UST_PID_CHANNEL_BLOCKING_TIMEOUT; |
| 108 | extended_attr->monitor_timer_interval = |
| 109 | DEFAULT_UST_PID_CHANNEL_MONITOR_TIMER; |
| 110 | break; |
| 111 | } |
| 112 | break; |
| 113 | default: |
| 114 | goto error; /* Not implemented */ |
| 115 | } |
| 116 | |
| 117 | if (snprintf(chan->name, sizeof(chan->name), "%s", |
| 118 | channel_name) < 0) { |
| 119 | PERROR("snprintf default channel name"); |
| 120 | goto error; |
| 121 | } |
| 122 | return chan; |
| 123 | |
| 124 | error: |
| 125 | free(extended_attr); |
| 126 | free(chan); |
| 127 | error_alloc: |
| 128 | return NULL; |
| 129 | } |
| 130 | |
| 131 | void channel_attr_destroy(struct lttng_channel *channel) |
| 132 | { |
| 133 | if (!channel) { |
| 134 | return; |
| 135 | } |
| 136 | free(channel->attr.extended.ptr); |
| 137 | free(channel); |
| 138 | } |
| 139 | |
| 140 | /* |
| 141 | * Disable kernel channel of the kernel session. |
| 142 | */ |
| 143 | int channel_kernel_disable(struct ltt_kernel_session *ksession, |
| 144 | char *channel_name) |
| 145 | { |
| 146 | int ret; |
| 147 | struct ltt_kernel_channel *kchan; |
| 148 | |
| 149 | assert(ksession); |
| 150 | assert(channel_name); |
| 151 | |
| 152 | kchan = trace_kernel_get_channel_by_name(channel_name, ksession); |
| 153 | if (kchan == NULL) { |
| 154 | ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND; |
| 155 | goto error; |
| 156 | } |
| 157 | |
| 158 | /* Only if channel is enabled disable it. */ |
| 159 | if (kchan->enabled == 1) { |
| 160 | ret = kernel_disable_channel(kchan); |
| 161 | if (ret < 0 && ret != -EEXIST) { |
| 162 | ret = LTTNG_ERR_KERN_CHAN_DISABLE_FAIL; |
| 163 | goto error; |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | ret = LTTNG_OK; |
| 168 | |
| 169 | error: |
| 170 | return ret; |
| 171 | } |
| 172 | |
| 173 | /* |
| 174 | * Enable kernel channel of the kernel session. |
| 175 | */ |
| 176 | int channel_kernel_enable(struct ltt_kernel_session *ksession, |
| 177 | struct ltt_kernel_channel *kchan) |
| 178 | { |
| 179 | int ret; |
| 180 | |
| 181 | assert(ksession); |
| 182 | assert(kchan); |
| 183 | |
| 184 | if (kchan->enabled == 0) { |
| 185 | ret = kernel_enable_channel(kchan); |
| 186 | if (ret < 0) { |
| 187 | ret = LTTNG_ERR_KERN_CHAN_ENABLE_FAIL; |
| 188 | goto error; |
| 189 | } |
| 190 | } else { |
| 191 | ret = LTTNG_ERR_KERN_CHAN_EXIST; |
| 192 | goto error; |
| 193 | } |
| 194 | |
| 195 | ret = LTTNG_OK; |
| 196 | |
| 197 | error: |
| 198 | return ret; |
| 199 | } |
| 200 | |
| 201 | static int channel_validate(struct lttng_channel *attr) |
| 202 | { |
| 203 | /* |
| 204 | * The ringbuffer (both in user space and kernel) behaves badly |
| 205 | * in overwrite mode and with less than 2 subbuffers so block it |
| 206 | * right away and send back an invalid attribute error. |
| 207 | */ |
| 208 | if (attr->attr.overwrite && attr->attr.num_subbuf < 2) { |
| 209 | return -1; |
| 210 | } |
| 211 | return 0; |
| 212 | } |
| 213 | |
| 214 | static int channel_validate_kernel(struct lttng_channel *attr) |
| 215 | { |
| 216 | /* Kernel channels do not support blocking timeout. */ |
| 217 | if (((struct lttng_channel_extended *)attr->attr.extended.ptr)->blocking_timeout) { |
| 218 | return -1; |
| 219 | } |
| 220 | return 0; |
| 221 | } |
| 222 | |
| 223 | /* |
| 224 | * Create kernel channel of the kernel session and notify kernel thread. |
| 225 | */ |
| 226 | int channel_kernel_create(struct ltt_kernel_session *ksession, |
| 227 | struct lttng_channel *attr, int kernel_pipe) |
| 228 | { |
| 229 | int ret; |
| 230 | struct lttng_channel *defattr = NULL; |
| 231 | |
| 232 | assert(ksession); |
| 233 | |
| 234 | /* Creating channel attributes if needed */ |
| 235 | if (attr == NULL) { |
| 236 | defattr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL, |
| 237 | LTTNG_BUFFER_GLOBAL); |
| 238 | if (defattr == NULL) { |
| 239 | ret = LTTNG_ERR_FATAL; |
| 240 | goto error; |
| 241 | } |
| 242 | attr = defattr; |
| 243 | } |
| 244 | |
| 245 | /* |
| 246 | * Set the overwrite mode for this channel based on the session |
| 247 | * type unless the client explicitly overrides the channel mode. |
| 248 | */ |
| 249 | if (attr->attr.overwrite == DEFAULT_CHANNEL_OVERWRITE) { |
| 250 | attr->attr.overwrite = !!ksession->snapshot_mode; |
| 251 | } |
| 252 | |
| 253 | /* Validate common channel properties. */ |
| 254 | if (channel_validate(attr) < 0) { |
| 255 | ret = LTTNG_ERR_INVALID; |
| 256 | goto error; |
| 257 | } |
| 258 | |
| 259 | if (channel_validate_kernel(attr) < 0) { |
| 260 | ret = LTTNG_ERR_INVALID; |
| 261 | goto error; |
| 262 | } |
| 263 | |
| 264 | /* Channel not found, creating it */ |
| 265 | ret = kernel_create_channel(ksession, attr); |
| 266 | if (ret < 0) { |
| 267 | ret = LTTNG_ERR_KERN_CHAN_FAIL; |
| 268 | goto error; |
| 269 | } |
| 270 | |
| 271 | /* Notify kernel thread that there is a new channel */ |
| 272 | ret = notify_thread_pipe(kernel_pipe); |
| 273 | if (ret < 0) { |
| 274 | ret = LTTNG_ERR_FATAL; |
| 275 | goto error; |
| 276 | } |
| 277 | |
| 278 | ret = LTTNG_OK; |
| 279 | error: |
| 280 | channel_attr_destroy(defattr); |
| 281 | return ret; |
| 282 | } |
| 283 | |
| 284 | /* |
| 285 | * Enable UST channel for session and domain. |
| 286 | */ |
| 287 | int channel_ust_enable(struct ltt_ust_session *usess, |
| 288 | struct ltt_ust_channel *uchan) |
| 289 | { |
| 290 | int ret = LTTNG_OK; |
| 291 | |
| 292 | assert(usess); |
| 293 | assert(uchan); |
| 294 | |
| 295 | /* If already enabled, everything is OK */ |
| 296 | if (uchan->enabled) { |
| 297 | DBG3("Channel %s already enabled. Skipping", uchan->name); |
| 298 | ret = LTTNG_ERR_UST_CHAN_EXIST; |
| 299 | goto end; |
| 300 | } else { |
| 301 | uchan->enabled = 1; |
| 302 | DBG2("Channel %s enabled successfully", uchan->name); |
| 303 | } |
| 304 | |
| 305 | if (!usess->active) { |
| 306 | /* |
| 307 | * The channel will be activated against the apps |
| 308 | * when the session is started as part of the |
| 309 | * application channel "synchronize" operation. |
| 310 | */ |
| 311 | goto end; |
| 312 | } |
| 313 | |
| 314 | DBG2("Channel %s being enabled in UST domain", uchan->name); |
| 315 | |
| 316 | /* |
| 317 | * Enable channel for UST global domain on all applications. Ignore return |
| 318 | * value here since whatever error we got, it means that the channel was |
| 319 | * not created on one or many registered applications and we can not report |
| 320 | * this to the user yet. However, at this stage, the channel was |
| 321 | * successfully created on the session daemon side so the enable-channel |
| 322 | * command is a success. |
| 323 | */ |
| 324 | (void) ust_app_enable_channel_glb(usess, uchan); |
| 325 | |
| 326 | |
| 327 | end: |
| 328 | return ret; |
| 329 | } |
| 330 | |
| 331 | /* |
| 332 | * Create UST channel for session and domain. |
| 333 | */ |
| 334 | int channel_ust_create(struct ltt_ust_session *usess, |
| 335 | struct lttng_channel *attr, enum lttng_buffer_type type) |
| 336 | { |
| 337 | int ret = LTTNG_OK; |
| 338 | struct ltt_ust_channel *uchan = NULL; |
| 339 | struct lttng_channel *defattr = NULL; |
| 340 | enum lttng_domain_type domain = LTTNG_DOMAIN_UST; |
| 341 | bool chan_published = false; |
| 342 | |
| 343 | assert(usess); |
| 344 | |
| 345 | /* Creating channel attributes if needed */ |
| 346 | if (attr == NULL) { |
| 347 | defattr = channel_new_default_attr(LTTNG_DOMAIN_UST, type); |
| 348 | if (defattr == NULL) { |
| 349 | ret = LTTNG_ERR_FATAL; |
| 350 | goto error; |
| 351 | } |
| 352 | attr = defattr; |
| 353 | } else { |
| 354 | /* |
| 355 | * HACK: Set the channel's subdomain (JUL, Log4j, Python, etc.) |
| 356 | * based on the default name. |
| 357 | */ |
| 358 | if (!strcmp(attr->name, DEFAULT_JUL_CHANNEL_NAME)) { |
| 359 | domain = LTTNG_DOMAIN_JUL; |
| 360 | } else if (!strcmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME)) { |
| 361 | domain = LTTNG_DOMAIN_LOG4J; |
| 362 | } else if (!strcmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME)) { |
| 363 | domain = LTTNG_DOMAIN_PYTHON; |
| 364 | } |
| 365 | } |
| 366 | |
| 367 | /* |
| 368 | * Set the overwrite mode for this channel based on the session |
| 369 | * type unless the client explicitly overrides the channel mode. |
| 370 | */ |
| 371 | if (attr->attr.overwrite == DEFAULT_CHANNEL_OVERWRITE) { |
| 372 | attr->attr.overwrite = !!usess->snapshot_mode; |
| 373 | } |
| 374 | |
| 375 | /* Enforce mmap output for snapshot sessions. */ |
| 376 | if (usess->snapshot_mode) { |
| 377 | attr->attr.output = LTTNG_EVENT_MMAP; |
| 378 | } |
| 379 | |
| 380 | /* Validate common channel properties. */ |
| 381 | if (channel_validate(attr) < 0) { |
| 382 | ret = LTTNG_ERR_INVALID; |
| 383 | goto error; |
| 384 | } |
| 385 | |
| 386 | /* |
| 387 | * Validate UST buffer size and number of buffers: must both be power of 2 |
| 388 | * and nonzero. We validate right here for UST, because applications will |
| 389 | * not report the error to the user (unlike kernel tracing). |
| 390 | */ |
| 391 | if (!attr->attr.subbuf_size || |
| 392 | (attr->attr.subbuf_size & (attr->attr.subbuf_size - 1))) { |
| 393 | ret = LTTNG_ERR_INVALID; |
| 394 | goto error; |
| 395 | } |
| 396 | |
| 397 | /* |
| 398 | * Invalid subbuffer size if it's lower then the page size. |
| 399 | */ |
| 400 | if (attr->attr.subbuf_size < the_page_size) { |
| 401 | ret = LTTNG_ERR_INVALID; |
| 402 | goto error; |
| 403 | } |
| 404 | |
| 405 | if (!attr->attr.num_subbuf || |
| 406 | (attr->attr.num_subbuf & (attr->attr.num_subbuf - 1))) { |
| 407 | ret = LTTNG_ERR_INVALID; |
| 408 | goto error; |
| 409 | } |
| 410 | |
| 411 | if (attr->attr.output != LTTNG_EVENT_MMAP) { |
| 412 | ret = LTTNG_ERR_NOT_SUPPORTED; |
| 413 | goto error; |
| 414 | } |
| 415 | |
| 416 | /* |
| 417 | * The tracefile_size should not be < to the subbuf_size, otherwise |
| 418 | * we won't be able to write the packets on disk |
| 419 | */ |
| 420 | if ((attr->attr.tracefile_size > 0) && |
| 421 | (attr->attr.tracefile_size < attr->attr.subbuf_size)) { |
| 422 | ret = LTTNG_ERR_INVALID; |
| 423 | goto error; |
| 424 | } |
| 425 | |
| 426 | /* Validate buffer type. */ |
| 427 | switch (type) { |
| 428 | case LTTNG_BUFFER_PER_PID: |
| 429 | break; |
| 430 | case LTTNG_BUFFER_PER_UID: |
| 431 | break; |
| 432 | default: |
| 433 | ret = LTTNG_ERR_BUFFER_NOT_SUPPORTED; |
| 434 | goto error; |
| 435 | } |
| 436 | |
| 437 | /* Create UST channel */ |
| 438 | uchan = trace_ust_create_channel(attr, domain); |
| 439 | if (uchan == NULL) { |
| 440 | ret = LTTNG_ERR_FATAL; |
| 441 | goto error; |
| 442 | } |
| 443 | |
| 444 | uchan->enabled = 1; |
| 445 | if (trace_ust_is_max_id(usess->used_channel_id)) { |
| 446 | ret = LTTNG_ERR_UST_CHAN_FAIL; |
| 447 | goto error; |
| 448 | } |
| 449 | uchan->id = trace_ust_get_next_chan_id(usess); |
| 450 | |
| 451 | DBG2("Channel %s is being created for UST with buffer %d and id %" PRIu64, |
| 452 | uchan->name, type, uchan->id); |
| 453 | |
| 454 | /* Flag session buffer type. */ |
| 455 | if (!usess->buffer_type_changed) { |
| 456 | usess->buffer_type = type; |
| 457 | usess->buffer_type_changed = 1; |
| 458 | } else if (usess->buffer_type != type) { |
| 459 | /* Buffer type was already set. Refuse to create channel. */ |
| 460 | ret = LTTNG_ERR_BUFFER_TYPE_MISMATCH; |
| 461 | goto error_free_chan; |
| 462 | } |
| 463 | |
| 464 | /* Adding the channel to the channel hash table. */ |
| 465 | rcu_read_lock(); |
| 466 | if (strncmp(uchan->name, DEFAULT_METADATA_NAME, |
| 467 | sizeof(uchan->name))) { |
| 468 | lttng_ht_add_unique_str(usess->domain_global.channels, &uchan->node); |
| 469 | chan_published = true; |
| 470 | } else { |
| 471 | /* |
| 472 | * Copy channel attribute to session if this is metadata so if NO |
| 473 | * application exists we can access that data in the shadow copy during |
| 474 | * the global update of newly registered application. |
| 475 | */ |
| 476 | memcpy(&usess->metadata_attr, &uchan->attr, |
| 477 | sizeof(usess->metadata_attr)); |
| 478 | } |
| 479 | rcu_read_unlock(); |
| 480 | |
| 481 | DBG2("Channel %s created successfully", uchan->name); |
| 482 | if (domain != LTTNG_DOMAIN_UST) { |
| 483 | struct agent *agt = trace_ust_find_agent(usess, domain); |
| 484 | |
| 485 | if (!agt) { |
| 486 | agt = agent_create(domain); |
| 487 | if (!agt) { |
| 488 | ret = LTTNG_ERR_NOMEM; |
| 489 | goto error_remove_chan; |
| 490 | } |
| 491 | agent_add(agt, usess->agents); |
| 492 | } |
| 493 | } |
| 494 | |
| 495 | channel_attr_destroy(defattr); |
| 496 | return LTTNG_OK; |
| 497 | |
| 498 | error_remove_chan: |
| 499 | if (chan_published) { |
| 500 | trace_ust_delete_channel(usess->domain_global.channels, uchan); |
| 501 | } |
| 502 | error_free_chan: |
| 503 | trace_ust_destroy_channel(uchan); |
| 504 | error: |
| 505 | channel_attr_destroy(defattr); |
| 506 | return ret; |
| 507 | } |
| 508 | |
| 509 | /* |
| 510 | * Disable UST channel for session and domain. |
| 511 | */ |
| 512 | int channel_ust_disable(struct ltt_ust_session *usess, |
| 513 | struct ltt_ust_channel *uchan) |
| 514 | { |
| 515 | int ret = LTTNG_OK; |
| 516 | |
| 517 | assert(usess); |
| 518 | assert(uchan); |
| 519 | |
| 520 | /* Already disabled */ |
| 521 | if (uchan->enabled == 0) { |
| 522 | DBG2("Channel UST %s already disabled", uchan->name); |
| 523 | goto end; |
| 524 | } |
| 525 | |
| 526 | uchan->enabled = 0; |
| 527 | |
| 528 | /* |
| 529 | * If session is inactive we don't notify the tracer right away. We |
| 530 | * wait for the next synchronization. |
| 531 | */ |
| 532 | if (!usess->active) { |
| 533 | goto end; |
| 534 | } |
| 535 | |
| 536 | DBG2("Channel %s being disabled in UST global domain", uchan->name); |
| 537 | /* Disable channel for global domain */ |
| 538 | ret = ust_app_disable_channel_glb(usess, uchan); |
| 539 | if (ret < 0 && ret != -LTTNG_UST_ERR_EXIST) { |
| 540 | ret = LTTNG_ERR_UST_CHAN_DISABLE_FAIL; |
| 541 | goto error; |
| 542 | } |
| 543 | |
| 544 | DBG2("Channel %s disabled successfully", uchan->name); |
| 545 | |
| 546 | return LTTNG_OK; |
| 547 | |
| 548 | end: |
| 549 | error: |
| 550 | return ret; |
| 551 | } |