| 1 | /* |
| 2 | * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca> |
| 3 | * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 4 | * 2012 - David Goulet <dgoulet@efficios.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License, version 2 only, |
| 8 | * as published by the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 13 | * more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License along |
| 16 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 17 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 18 | */ |
| 19 | |
| 20 | #define _GNU_SOURCE |
| 21 | #include <assert.h> |
| 22 | #include <poll.h> |
| 23 | #include <pthread.h> |
| 24 | #include <stdlib.h> |
| 25 | #include <string.h> |
| 26 | #include <sys/mman.h> |
| 27 | #include <sys/socket.h> |
| 28 | #include <sys/types.h> |
| 29 | #include <unistd.h> |
| 30 | #include <inttypes.h> |
| 31 | |
| 32 | #include <common/common.h> |
| 33 | #include <common/kernel-ctl/kernel-ctl.h> |
| 34 | #include <common/sessiond-comm/relayd.h> |
| 35 | #include <common/sessiond-comm/sessiond-comm.h> |
| 36 | #include <common/kernel-consumer/kernel-consumer.h> |
| 37 | #include <common/relayd/relayd.h> |
| 38 | #include <common/ust-consumer/ust-consumer.h> |
| 39 | |
| 40 | #include "consumer.h" |
| 41 | |
| 42 | struct lttng_consumer_global_data consumer_data = { |
| 43 | .stream_count = 0, |
| 44 | .need_update = 1, |
| 45 | .type = LTTNG_CONSUMER_UNKNOWN, |
| 46 | }; |
| 47 | |
| 48 | /* timeout parameter, to control the polling thread grace period. */ |
| 49 | int consumer_poll_timeout = -1; |
| 50 | |
| 51 | /* |
| 52 | * Flag to inform the polling thread to quit when all fd hung up. Updated by |
| 53 | * the consumer_thread_receive_fds when it notices that all fds has hung up. |
| 54 | * Also updated by the signal handler (consumer_should_exit()). Read by the |
| 55 | * polling threads. |
| 56 | */ |
| 57 | volatile int consumer_quit = 0; |
| 58 | |
| 59 | /* |
| 60 | * Find a stream. The consumer_data.lock must be locked during this |
| 61 | * call. |
| 62 | */ |
| 63 | static struct lttng_consumer_stream *consumer_find_stream(int key) |
| 64 | { |
| 65 | struct lttng_ht_iter iter; |
| 66 | struct lttng_ht_node_ulong *node; |
| 67 | struct lttng_consumer_stream *stream = NULL; |
| 68 | |
| 69 | /* Negative keys are lookup failures */ |
| 70 | if (key < 0) |
| 71 | return NULL; |
| 72 | |
| 73 | rcu_read_lock(); |
| 74 | |
| 75 | lttng_ht_lookup(consumer_data.stream_ht, (void *)((unsigned long) key), |
| 76 | &iter); |
| 77 | node = lttng_ht_iter_get_node_ulong(&iter); |
| 78 | if (node != NULL) { |
| 79 | stream = caa_container_of(node, struct lttng_consumer_stream, node); |
| 80 | } |
| 81 | |
| 82 | rcu_read_unlock(); |
| 83 | |
| 84 | return stream; |
| 85 | } |
| 86 | |
| 87 | static void consumer_steal_stream_key(int key) |
| 88 | { |
| 89 | struct lttng_consumer_stream *stream; |
| 90 | |
| 91 | rcu_read_lock(); |
| 92 | stream = consumer_find_stream(key); |
| 93 | if (stream) { |
| 94 | stream->key = -1; |
| 95 | /* |
| 96 | * We don't want the lookup to match, but we still need |
| 97 | * to iterate on this stream when iterating over the hash table. Just |
| 98 | * change the node key. |
| 99 | */ |
| 100 | stream->node.key = -1; |
| 101 | } |
| 102 | rcu_read_unlock(); |
| 103 | } |
| 104 | |
| 105 | static struct lttng_consumer_channel *consumer_find_channel(int key) |
| 106 | { |
| 107 | struct lttng_ht_iter iter; |
| 108 | struct lttng_ht_node_ulong *node; |
| 109 | struct lttng_consumer_channel *channel = NULL; |
| 110 | |
| 111 | /* Negative keys are lookup failures */ |
| 112 | if (key < 0) |
| 113 | return NULL; |
| 114 | |
| 115 | rcu_read_lock(); |
| 116 | |
| 117 | lttng_ht_lookup(consumer_data.channel_ht, (void *)((unsigned long) key), |
| 118 | &iter); |
| 119 | node = lttng_ht_iter_get_node_ulong(&iter); |
| 120 | if (node != NULL) { |
| 121 | channel = caa_container_of(node, struct lttng_consumer_channel, node); |
| 122 | } |
| 123 | |
| 124 | rcu_read_unlock(); |
| 125 | |
| 126 | return channel; |
| 127 | } |
| 128 | |
| 129 | static void consumer_steal_channel_key(int key) |
| 130 | { |
| 131 | struct lttng_consumer_channel *channel; |
| 132 | |
| 133 | rcu_read_lock(); |
| 134 | channel = consumer_find_channel(key); |
| 135 | if (channel) { |
| 136 | channel->key = -1; |
| 137 | /* |
| 138 | * We don't want the lookup to match, but we still need |
| 139 | * to iterate on this channel when iterating over the hash table. Just |
| 140 | * change the node key. |
| 141 | */ |
| 142 | channel->node.key = -1; |
| 143 | } |
| 144 | rcu_read_unlock(); |
| 145 | } |
| 146 | |
| 147 | static |
| 148 | void consumer_free_stream(struct rcu_head *head) |
| 149 | { |
| 150 | struct lttng_ht_node_ulong *node = |
| 151 | caa_container_of(head, struct lttng_ht_node_ulong, head); |
| 152 | struct lttng_consumer_stream *stream = |
| 153 | caa_container_of(node, struct lttng_consumer_stream, node); |
| 154 | |
| 155 | free(stream); |
| 156 | } |
| 157 | |
| 158 | /* |
| 159 | * RCU protected relayd socket pair free. |
| 160 | */ |
| 161 | static void consumer_rcu_free_relayd(struct rcu_head *head) |
| 162 | { |
| 163 | struct lttng_ht_node_ulong *node = |
| 164 | caa_container_of(head, struct lttng_ht_node_ulong, head); |
| 165 | struct consumer_relayd_sock_pair *relayd = |
| 166 | caa_container_of(node, struct consumer_relayd_sock_pair, node); |
| 167 | |
| 168 | free(relayd); |
| 169 | } |
| 170 | |
| 171 | /* |
| 172 | * Destroy and free relayd socket pair object. |
| 173 | * |
| 174 | * This function MUST be called with the consumer_data lock acquired. |
| 175 | */ |
| 176 | void consumer_destroy_relayd(struct consumer_relayd_sock_pair *relayd) |
| 177 | { |
| 178 | int ret; |
| 179 | struct lttng_ht_iter iter; |
| 180 | |
| 181 | if (relayd == NULL) { |
| 182 | return; |
| 183 | } |
| 184 | |
| 185 | DBG("Consumer destroy and close relayd socket pair"); |
| 186 | |
| 187 | iter.iter.node = &relayd->node.node; |
| 188 | ret = lttng_ht_del(consumer_data.relayd_ht, &iter); |
| 189 | if (ret != 0) { |
| 190 | /* We assume the relayd was already destroyed */ |
| 191 | return; |
| 192 | } |
| 193 | |
| 194 | /* Close all sockets */ |
| 195 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); |
| 196 | (void) relayd_close(&relayd->control_sock); |
| 197 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); |
| 198 | (void) relayd_close(&relayd->data_sock); |
| 199 | |
| 200 | /* RCU free() call */ |
| 201 | call_rcu(&relayd->node.head, consumer_rcu_free_relayd); |
| 202 | } |
| 203 | |
| 204 | /* |
| 205 | * Remove a stream from the global list protected by a mutex. This |
| 206 | * function is also responsible for freeing its data structures. |
| 207 | */ |
| 208 | void consumer_del_stream(struct lttng_consumer_stream *stream) |
| 209 | { |
| 210 | int ret; |
| 211 | struct lttng_ht_iter iter; |
| 212 | struct lttng_consumer_channel *free_chan = NULL; |
| 213 | struct consumer_relayd_sock_pair *relayd; |
| 214 | |
| 215 | assert(stream); |
| 216 | |
| 217 | pthread_mutex_lock(&consumer_data.lock); |
| 218 | |
| 219 | switch (consumer_data.type) { |
| 220 | case LTTNG_CONSUMER_KERNEL: |
| 221 | if (stream->mmap_base != NULL) { |
| 222 | ret = munmap(stream->mmap_base, stream->mmap_len); |
| 223 | if (ret != 0) { |
| 224 | perror("munmap"); |
| 225 | } |
| 226 | } |
| 227 | break; |
| 228 | case LTTNG_CONSUMER32_UST: |
| 229 | case LTTNG_CONSUMER64_UST: |
| 230 | lttng_ustconsumer_del_stream(stream); |
| 231 | break; |
| 232 | default: |
| 233 | ERR("Unknown consumer_data type"); |
| 234 | assert(0); |
| 235 | goto end; |
| 236 | } |
| 237 | |
| 238 | rcu_read_lock(); |
| 239 | iter.iter.node = &stream->node.node; |
| 240 | ret = lttng_ht_del(consumer_data.stream_ht, &iter); |
| 241 | assert(!ret); |
| 242 | |
| 243 | rcu_read_unlock(); |
| 244 | |
| 245 | if (consumer_data.stream_count <= 0) { |
| 246 | goto end; |
| 247 | } |
| 248 | consumer_data.stream_count--; |
| 249 | if (!stream) { |
| 250 | goto end; |
| 251 | } |
| 252 | if (stream->out_fd >= 0) { |
| 253 | ret = close(stream->out_fd); |
| 254 | if (ret) { |
| 255 | PERROR("close"); |
| 256 | } |
| 257 | } |
| 258 | if (stream->wait_fd >= 0 && !stream->wait_fd_is_copy) { |
| 259 | ret = close(stream->wait_fd); |
| 260 | if (ret) { |
| 261 | PERROR("close"); |
| 262 | } |
| 263 | } |
| 264 | if (stream->shm_fd >= 0 && stream->wait_fd != stream->shm_fd) { |
| 265 | ret = close(stream->shm_fd); |
| 266 | if (ret) { |
| 267 | PERROR("close"); |
| 268 | } |
| 269 | } |
| 270 | |
| 271 | /* Check and cleanup relayd */ |
| 272 | rcu_read_lock(); |
| 273 | relayd = consumer_find_relayd(stream->net_seq_idx); |
| 274 | if (relayd != NULL) { |
| 275 | uatomic_dec(&relayd->refcount); |
| 276 | assert(uatomic_read(&relayd->refcount) >= 0); |
| 277 | |
| 278 | /* Closing streams requires to lock the control socket. */ |
| 279 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); |
| 280 | ret = relayd_send_close_stream(&relayd->control_sock, |
| 281 | stream->relayd_stream_id, |
| 282 | stream->next_net_seq_num - 1); |
| 283 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); |
| 284 | if (ret < 0) { |
| 285 | DBG("Unable to close stream on the relayd. Continuing"); |
| 286 | /* |
| 287 | * Continue here. There is nothing we can do for the relayd. |
| 288 | * Chances are that the relayd has closed the socket so we just |
| 289 | * continue cleaning up. |
| 290 | */ |
| 291 | } |
| 292 | |
| 293 | /* Both conditions are met, we destroy the relayd. */ |
| 294 | if (uatomic_read(&relayd->refcount) == 0 && |
| 295 | uatomic_read(&relayd->destroy_flag)) { |
| 296 | consumer_destroy_relayd(relayd); |
| 297 | } |
| 298 | } |
| 299 | rcu_read_unlock(); |
| 300 | |
| 301 | if (!--stream->chan->refcount) { |
| 302 | free_chan = stream->chan; |
| 303 | } |
| 304 | |
| 305 | |
| 306 | call_rcu(&stream->node.head, consumer_free_stream); |
| 307 | end: |
| 308 | consumer_data.need_update = 1; |
| 309 | pthread_mutex_unlock(&consumer_data.lock); |
| 310 | |
| 311 | if (free_chan) |
| 312 | consumer_del_channel(free_chan); |
| 313 | } |
| 314 | |
| 315 | struct lttng_consumer_stream *consumer_allocate_stream( |
| 316 | int channel_key, int stream_key, |
| 317 | int shm_fd, int wait_fd, |
| 318 | enum lttng_consumer_stream_state state, |
| 319 | uint64_t mmap_len, |
| 320 | enum lttng_event_output output, |
| 321 | const char *path_name, |
| 322 | uid_t uid, |
| 323 | gid_t gid, |
| 324 | int net_index, |
| 325 | int metadata_flag) |
| 326 | { |
| 327 | struct lttng_consumer_stream *stream; |
| 328 | int ret; |
| 329 | |
| 330 | stream = zmalloc(sizeof(*stream)); |
| 331 | if (stream == NULL) { |
| 332 | perror("malloc struct lttng_consumer_stream"); |
| 333 | goto end; |
| 334 | } |
| 335 | stream->chan = consumer_find_channel(channel_key); |
| 336 | if (!stream->chan) { |
| 337 | perror("Unable to find channel key"); |
| 338 | goto end; |
| 339 | } |
| 340 | stream->chan->refcount++; |
| 341 | stream->key = stream_key; |
| 342 | stream->shm_fd = shm_fd; |
| 343 | stream->wait_fd = wait_fd; |
| 344 | stream->out_fd = -1; |
| 345 | stream->out_fd_offset = 0; |
| 346 | stream->state = state; |
| 347 | stream->mmap_len = mmap_len; |
| 348 | stream->mmap_base = NULL; |
| 349 | stream->output = output; |
| 350 | stream->uid = uid; |
| 351 | stream->gid = gid; |
| 352 | stream->net_seq_idx = net_index; |
| 353 | stream->metadata_flag = metadata_flag; |
| 354 | strncpy(stream->path_name, path_name, sizeof(stream->path_name)); |
| 355 | stream->path_name[sizeof(stream->path_name) - 1] = '\0'; |
| 356 | lttng_ht_node_init_ulong(&stream->node, stream->key); |
| 357 | lttng_ht_node_init_ulong(&stream->waitfd_node, stream->wait_fd); |
| 358 | |
| 359 | switch (consumer_data.type) { |
| 360 | case LTTNG_CONSUMER_KERNEL: |
| 361 | break; |
| 362 | case LTTNG_CONSUMER32_UST: |
| 363 | case LTTNG_CONSUMER64_UST: |
| 364 | stream->cpu = stream->chan->cpucount++; |
| 365 | ret = lttng_ustconsumer_allocate_stream(stream); |
| 366 | if (ret) { |
| 367 | free(stream); |
| 368 | return NULL; |
| 369 | } |
| 370 | break; |
| 371 | default: |
| 372 | ERR("Unknown consumer_data type"); |
| 373 | assert(0); |
| 374 | goto end; |
| 375 | } |
| 376 | DBG("Allocated stream %s (key %d, shm_fd %d, wait_fd %d, mmap_len %llu, out_fd %d, net_seq_idx %d)", |
| 377 | stream->path_name, stream->key, |
| 378 | stream->shm_fd, |
| 379 | stream->wait_fd, |
| 380 | (unsigned long long) stream->mmap_len, |
| 381 | stream->out_fd, |
| 382 | stream->net_seq_idx); |
| 383 | end: |
| 384 | return stream; |
| 385 | } |
| 386 | |
| 387 | /* |
| 388 | * Add a stream to the global list protected by a mutex. |
| 389 | */ |
| 390 | int consumer_add_stream(struct lttng_consumer_stream *stream) |
| 391 | { |
| 392 | int ret = 0; |
| 393 | struct lttng_ht_node_ulong *node; |
| 394 | struct lttng_ht_iter iter; |
| 395 | struct consumer_relayd_sock_pair *relayd; |
| 396 | |
| 397 | pthread_mutex_lock(&consumer_data.lock); |
| 398 | /* Steal stream identifier, for UST */ |
| 399 | consumer_steal_stream_key(stream->key); |
| 400 | |
| 401 | rcu_read_lock(); |
| 402 | lttng_ht_lookup(consumer_data.stream_ht, |
| 403 | (void *)((unsigned long) stream->key), &iter); |
| 404 | node = lttng_ht_iter_get_node_ulong(&iter); |
| 405 | if (node != NULL) { |
| 406 | rcu_read_unlock(); |
| 407 | /* Stream already exist. Ignore the insertion */ |
| 408 | goto end; |
| 409 | } |
| 410 | |
| 411 | lttng_ht_add_unique_ulong(consumer_data.stream_ht, &stream->node); |
| 412 | |
| 413 | /* Check and cleanup relayd */ |
| 414 | relayd = consumer_find_relayd(stream->net_seq_idx); |
| 415 | if (relayd != NULL) { |
| 416 | uatomic_inc(&relayd->refcount); |
| 417 | } |
| 418 | rcu_read_unlock(); |
| 419 | |
| 420 | /* Update consumer data */ |
| 421 | consumer_data.stream_count++; |
| 422 | consumer_data.need_update = 1; |
| 423 | |
| 424 | switch (consumer_data.type) { |
| 425 | case LTTNG_CONSUMER_KERNEL: |
| 426 | break; |
| 427 | case LTTNG_CONSUMER32_UST: |
| 428 | case LTTNG_CONSUMER64_UST: |
| 429 | /* Streams are in CPU number order (we rely on this) */ |
| 430 | stream->cpu = stream->chan->nr_streams++; |
| 431 | break; |
| 432 | default: |
| 433 | ERR("Unknown consumer_data type"); |
| 434 | assert(0); |
| 435 | goto end; |
| 436 | } |
| 437 | |
| 438 | end: |
| 439 | pthread_mutex_unlock(&consumer_data.lock); |
| 440 | |
| 441 | return ret; |
| 442 | } |
| 443 | |
| 444 | /* |
| 445 | * Add relayd socket to global consumer data hashtable. RCU read side lock MUST |
| 446 | * be acquired before calling this. |
| 447 | */ |
| 448 | |
| 449 | int consumer_add_relayd(struct consumer_relayd_sock_pair *relayd) |
| 450 | { |
| 451 | int ret = 0; |
| 452 | struct lttng_ht_node_ulong *node; |
| 453 | struct lttng_ht_iter iter; |
| 454 | |
| 455 | if (relayd == NULL) { |
| 456 | ret = -1; |
| 457 | goto end; |
| 458 | } |
| 459 | |
| 460 | lttng_ht_lookup(consumer_data.relayd_ht, |
| 461 | (void *)((unsigned long) relayd->net_seq_idx), &iter); |
| 462 | node = lttng_ht_iter_get_node_ulong(&iter); |
| 463 | if (node != NULL) { |
| 464 | /* Relayd already exist. Ignore the insertion */ |
| 465 | goto end; |
| 466 | } |
| 467 | lttng_ht_add_unique_ulong(consumer_data.relayd_ht, &relayd->node); |
| 468 | |
| 469 | end: |
| 470 | return ret; |
| 471 | } |
| 472 | |
| 473 | /* |
| 474 | * Allocate and return a consumer relayd socket. |
| 475 | */ |
| 476 | struct consumer_relayd_sock_pair *consumer_allocate_relayd_sock_pair( |
| 477 | int net_seq_idx) |
| 478 | { |
| 479 | struct consumer_relayd_sock_pair *obj = NULL; |
| 480 | |
| 481 | /* Negative net sequence index is a failure */ |
| 482 | if (net_seq_idx < 0) { |
| 483 | goto error; |
| 484 | } |
| 485 | |
| 486 | obj = zmalloc(sizeof(struct consumer_relayd_sock_pair)); |
| 487 | if (obj == NULL) { |
| 488 | PERROR("zmalloc relayd sock"); |
| 489 | goto error; |
| 490 | } |
| 491 | |
| 492 | obj->net_seq_idx = net_seq_idx; |
| 493 | obj->refcount = 0; |
| 494 | obj->destroy_flag = 0; |
| 495 | lttng_ht_node_init_ulong(&obj->node, obj->net_seq_idx); |
| 496 | pthread_mutex_init(&obj->ctrl_sock_mutex, NULL); |
| 497 | |
| 498 | error: |
| 499 | return obj; |
| 500 | } |
| 501 | |
| 502 | /* |
| 503 | * Find a relayd socket pair in the global consumer data. |
| 504 | * |
| 505 | * Return the object if found else NULL. |
| 506 | * RCU read-side lock must be held across this call and while using the |
| 507 | * returned object. |
| 508 | */ |
| 509 | struct consumer_relayd_sock_pair *consumer_find_relayd(int key) |
| 510 | { |
| 511 | struct lttng_ht_iter iter; |
| 512 | struct lttng_ht_node_ulong *node; |
| 513 | struct consumer_relayd_sock_pair *relayd = NULL; |
| 514 | |
| 515 | /* Negative keys are lookup failures */ |
| 516 | if (key < 0) { |
| 517 | goto error; |
| 518 | } |
| 519 | |
| 520 | lttng_ht_lookup(consumer_data.relayd_ht, (void *)((unsigned long) key), |
| 521 | &iter); |
| 522 | node = lttng_ht_iter_get_node_ulong(&iter); |
| 523 | if (node != NULL) { |
| 524 | relayd = caa_container_of(node, struct consumer_relayd_sock_pair, node); |
| 525 | } |
| 526 | |
| 527 | error: |
| 528 | return relayd; |
| 529 | } |
| 530 | |
| 531 | /* |
| 532 | * Handle stream for relayd transmission if the stream applies for network |
| 533 | * streaming where the net sequence index is set. |
| 534 | * |
| 535 | * Return destination file descriptor or negative value on error. |
| 536 | */ |
| 537 | static int write_relayd_stream_header(struct lttng_consumer_stream *stream, |
| 538 | size_t data_size, struct consumer_relayd_sock_pair *relayd) |
| 539 | { |
| 540 | int outfd = -1, ret; |
| 541 | struct lttcomm_relayd_data_hdr data_hdr; |
| 542 | |
| 543 | /* Safety net */ |
| 544 | assert(stream); |
| 545 | assert(relayd); |
| 546 | |
| 547 | /* Reset data header */ |
| 548 | memset(&data_hdr, 0, sizeof(data_hdr)); |
| 549 | |
| 550 | if (stream->metadata_flag) { |
| 551 | /* Caller MUST acquire the relayd control socket lock */ |
| 552 | ret = relayd_send_metadata(&relayd->control_sock, data_size); |
| 553 | if (ret < 0) { |
| 554 | goto error; |
| 555 | } |
| 556 | |
| 557 | /* Metadata are always sent on the control socket. */ |
| 558 | outfd = relayd->control_sock.fd; |
| 559 | } else { |
| 560 | /* Set header with stream information */ |
| 561 | data_hdr.stream_id = htobe64(stream->relayd_stream_id); |
| 562 | data_hdr.data_size = htobe32(data_size); |
| 563 | data_hdr.net_seq_num = htobe64(stream->next_net_seq_num++); |
| 564 | /* Other fields are zeroed previously */ |
| 565 | |
| 566 | ret = relayd_send_data_hdr(&relayd->data_sock, &data_hdr, |
| 567 | sizeof(data_hdr)); |
| 568 | if (ret < 0) { |
| 569 | goto error; |
| 570 | } |
| 571 | |
| 572 | /* Set to go on data socket */ |
| 573 | outfd = relayd->data_sock.fd; |
| 574 | } |
| 575 | |
| 576 | error: |
| 577 | return outfd; |
| 578 | } |
| 579 | |
| 580 | /* |
| 581 | * Update a stream according to what we just received. |
| 582 | */ |
| 583 | void consumer_change_stream_state(int stream_key, |
| 584 | enum lttng_consumer_stream_state state) |
| 585 | { |
| 586 | struct lttng_consumer_stream *stream; |
| 587 | |
| 588 | pthread_mutex_lock(&consumer_data.lock); |
| 589 | stream = consumer_find_stream(stream_key); |
| 590 | if (stream) { |
| 591 | stream->state = state; |
| 592 | } |
| 593 | consumer_data.need_update = 1; |
| 594 | pthread_mutex_unlock(&consumer_data.lock); |
| 595 | } |
| 596 | |
| 597 | static |
| 598 | void consumer_free_channel(struct rcu_head *head) |
| 599 | { |
| 600 | struct lttng_ht_node_ulong *node = |
| 601 | caa_container_of(head, struct lttng_ht_node_ulong, head); |
| 602 | struct lttng_consumer_channel *channel = |
| 603 | caa_container_of(node, struct lttng_consumer_channel, node); |
| 604 | |
| 605 | free(channel); |
| 606 | } |
| 607 | |
| 608 | /* |
| 609 | * Remove a channel from the global list protected by a mutex. This |
| 610 | * function is also responsible for freeing its data structures. |
| 611 | */ |
| 612 | void consumer_del_channel(struct lttng_consumer_channel *channel) |
| 613 | { |
| 614 | int ret; |
| 615 | struct lttng_ht_iter iter; |
| 616 | |
| 617 | pthread_mutex_lock(&consumer_data.lock); |
| 618 | |
| 619 | switch (consumer_data.type) { |
| 620 | case LTTNG_CONSUMER_KERNEL: |
| 621 | break; |
| 622 | case LTTNG_CONSUMER32_UST: |
| 623 | case LTTNG_CONSUMER64_UST: |
| 624 | lttng_ustconsumer_del_channel(channel); |
| 625 | break; |
| 626 | default: |
| 627 | ERR("Unknown consumer_data type"); |
| 628 | assert(0); |
| 629 | goto end; |
| 630 | } |
| 631 | |
| 632 | rcu_read_lock(); |
| 633 | iter.iter.node = &channel->node.node; |
| 634 | ret = lttng_ht_del(consumer_data.channel_ht, &iter); |
| 635 | assert(!ret); |
| 636 | rcu_read_unlock(); |
| 637 | |
| 638 | if (channel->mmap_base != NULL) { |
| 639 | ret = munmap(channel->mmap_base, channel->mmap_len); |
| 640 | if (ret != 0) { |
| 641 | perror("munmap"); |
| 642 | } |
| 643 | } |
| 644 | if (channel->wait_fd >= 0 && !channel->wait_fd_is_copy) { |
| 645 | ret = close(channel->wait_fd); |
| 646 | if (ret) { |
| 647 | PERROR("close"); |
| 648 | } |
| 649 | } |
| 650 | if (channel->shm_fd >= 0 && channel->wait_fd != channel->shm_fd) { |
| 651 | ret = close(channel->shm_fd); |
| 652 | if (ret) { |
| 653 | PERROR("close"); |
| 654 | } |
| 655 | } |
| 656 | |
| 657 | call_rcu(&channel->node.head, consumer_free_channel); |
| 658 | end: |
| 659 | pthread_mutex_unlock(&consumer_data.lock); |
| 660 | } |
| 661 | |
| 662 | struct lttng_consumer_channel *consumer_allocate_channel( |
| 663 | int channel_key, |
| 664 | int shm_fd, int wait_fd, |
| 665 | uint64_t mmap_len, |
| 666 | uint64_t max_sb_size) |
| 667 | { |
| 668 | struct lttng_consumer_channel *channel; |
| 669 | int ret; |
| 670 | |
| 671 | channel = zmalloc(sizeof(*channel)); |
| 672 | if (channel == NULL) { |
| 673 | perror("malloc struct lttng_consumer_channel"); |
| 674 | goto end; |
| 675 | } |
| 676 | channel->key = channel_key; |
| 677 | channel->shm_fd = shm_fd; |
| 678 | channel->wait_fd = wait_fd; |
| 679 | channel->mmap_len = mmap_len; |
| 680 | channel->max_sb_size = max_sb_size; |
| 681 | channel->refcount = 0; |
| 682 | channel->nr_streams = 0; |
| 683 | lttng_ht_node_init_ulong(&channel->node, channel->key); |
| 684 | |
| 685 | switch (consumer_data.type) { |
| 686 | case LTTNG_CONSUMER_KERNEL: |
| 687 | channel->mmap_base = NULL; |
| 688 | channel->mmap_len = 0; |
| 689 | break; |
| 690 | case LTTNG_CONSUMER32_UST: |
| 691 | case LTTNG_CONSUMER64_UST: |
| 692 | ret = lttng_ustconsumer_allocate_channel(channel); |
| 693 | if (ret) { |
| 694 | free(channel); |
| 695 | return NULL; |
| 696 | } |
| 697 | break; |
| 698 | default: |
| 699 | ERR("Unknown consumer_data type"); |
| 700 | assert(0); |
| 701 | goto end; |
| 702 | } |
| 703 | DBG("Allocated channel (key %d, shm_fd %d, wait_fd %d, mmap_len %llu, max_sb_size %llu)", |
| 704 | channel->key, channel->shm_fd, channel->wait_fd, |
| 705 | (unsigned long long) channel->mmap_len, |
| 706 | (unsigned long long) channel->max_sb_size); |
| 707 | end: |
| 708 | return channel; |
| 709 | } |
| 710 | |
| 711 | /* |
| 712 | * Add a channel to the global list protected by a mutex. |
| 713 | */ |
| 714 | int consumer_add_channel(struct lttng_consumer_channel *channel) |
| 715 | { |
| 716 | struct lttng_ht_node_ulong *node; |
| 717 | struct lttng_ht_iter iter; |
| 718 | |
| 719 | pthread_mutex_lock(&consumer_data.lock); |
| 720 | /* Steal channel identifier, for UST */ |
| 721 | consumer_steal_channel_key(channel->key); |
| 722 | rcu_read_lock(); |
| 723 | |
| 724 | lttng_ht_lookup(consumer_data.channel_ht, |
| 725 | (void *)((unsigned long) channel->key), &iter); |
| 726 | node = lttng_ht_iter_get_node_ulong(&iter); |
| 727 | if (node != NULL) { |
| 728 | /* Channel already exist. Ignore the insertion */ |
| 729 | goto end; |
| 730 | } |
| 731 | |
| 732 | lttng_ht_add_unique_ulong(consumer_data.channel_ht, &channel->node); |
| 733 | |
| 734 | end: |
| 735 | rcu_read_unlock(); |
| 736 | pthread_mutex_unlock(&consumer_data.lock); |
| 737 | |
| 738 | return 0; |
| 739 | } |
| 740 | |
| 741 | /* |
| 742 | * Allocate the pollfd structure and the local view of the out fds to avoid |
| 743 | * doing a lookup in the linked list and concurrency issues when writing is |
| 744 | * needed. Called with consumer_data.lock held. |
| 745 | * |
| 746 | * Returns the number of fds in the structures. |
| 747 | */ |
| 748 | int consumer_update_poll_array( |
| 749 | struct lttng_consumer_local_data *ctx, struct pollfd **pollfd, |
| 750 | struct lttng_consumer_stream **local_stream, |
| 751 | struct lttng_ht *metadata_ht) |
| 752 | { |
| 753 | int i = 0; |
| 754 | struct lttng_ht_iter iter; |
| 755 | struct lttng_consumer_stream *stream; |
| 756 | |
| 757 | DBG("Updating poll fd array"); |
| 758 | rcu_read_lock(); |
| 759 | cds_lfht_for_each_entry(consumer_data.stream_ht->ht, &iter.iter, stream, |
| 760 | node.node) { |
| 761 | if (stream->state != LTTNG_CONSUMER_ACTIVE_STREAM) { |
| 762 | continue; |
| 763 | } |
| 764 | DBG("Active FD %d", stream->wait_fd); |
| 765 | (*pollfd)[i].fd = stream->wait_fd; |
| 766 | (*pollfd)[i].events = POLLIN | POLLPRI; |
| 767 | if (stream->metadata_flag && metadata_ht) { |
| 768 | lttng_ht_add_unique_ulong(metadata_ht, &stream->waitfd_node); |
| 769 | DBG("Active FD added to metadata hash table"); |
| 770 | } |
| 771 | local_stream[i] = stream; |
| 772 | i++; |
| 773 | } |
| 774 | rcu_read_unlock(); |
| 775 | |
| 776 | /* |
| 777 | * Insert the consumer_poll_pipe at the end of the array and don't |
| 778 | * increment i so nb_fd is the number of real FD. |
| 779 | */ |
| 780 | (*pollfd)[i].fd = ctx->consumer_poll_pipe[0]; |
| 781 | (*pollfd)[i].events = POLLIN | POLLPRI; |
| 782 | return i; |
| 783 | } |
| 784 | |
| 785 | /* |
| 786 | * Poll on the should_quit pipe and the command socket return -1 on error and |
| 787 | * should exit, 0 if data is available on the command socket |
| 788 | */ |
| 789 | int lttng_consumer_poll_socket(struct pollfd *consumer_sockpoll) |
| 790 | { |
| 791 | int num_rdy; |
| 792 | |
| 793 | restart: |
| 794 | num_rdy = poll(consumer_sockpoll, 2, -1); |
| 795 | if (num_rdy == -1) { |
| 796 | /* |
| 797 | * Restart interrupted system call. |
| 798 | */ |
| 799 | if (errno == EINTR) { |
| 800 | goto restart; |
| 801 | } |
| 802 | perror("Poll error"); |
| 803 | goto exit; |
| 804 | } |
| 805 | if (consumer_sockpoll[0].revents & (POLLIN | POLLPRI)) { |
| 806 | DBG("consumer_should_quit wake up"); |
| 807 | goto exit; |
| 808 | } |
| 809 | return 0; |
| 810 | |
| 811 | exit: |
| 812 | return -1; |
| 813 | } |
| 814 | |
| 815 | /* |
| 816 | * Set the error socket. |
| 817 | */ |
| 818 | void lttng_consumer_set_error_sock( |
| 819 | struct lttng_consumer_local_data *ctx, int sock) |
| 820 | { |
| 821 | ctx->consumer_error_socket = sock; |
| 822 | } |
| 823 | |
| 824 | /* |
| 825 | * Set the command socket path. |
| 826 | */ |
| 827 | void lttng_consumer_set_command_sock_path( |
| 828 | struct lttng_consumer_local_data *ctx, char *sock) |
| 829 | { |
| 830 | ctx->consumer_command_sock_path = sock; |
| 831 | } |
| 832 | |
| 833 | /* |
| 834 | * Send return code to the session daemon. |
| 835 | * If the socket is not defined, we return 0, it is not a fatal error |
| 836 | */ |
| 837 | int lttng_consumer_send_error( |
| 838 | struct lttng_consumer_local_data *ctx, int cmd) |
| 839 | { |
| 840 | if (ctx->consumer_error_socket > 0) { |
| 841 | return lttcomm_send_unix_sock(ctx->consumer_error_socket, &cmd, |
| 842 | sizeof(enum lttcomm_sessiond_command)); |
| 843 | } |
| 844 | |
| 845 | return 0; |
| 846 | } |
| 847 | |
| 848 | /* |
| 849 | * Close all the tracefiles and stream fds, should be called when all instances |
| 850 | * are destroyed. |
| 851 | */ |
| 852 | void lttng_consumer_cleanup(void) |
| 853 | { |
| 854 | struct lttng_ht_iter iter; |
| 855 | struct lttng_ht_node_ulong *node; |
| 856 | |
| 857 | rcu_read_lock(); |
| 858 | |
| 859 | /* |
| 860 | * close all outfd. Called when there are no more threads running (after |
| 861 | * joining on the threads), no need to protect list iteration with mutex. |
| 862 | */ |
| 863 | cds_lfht_for_each_entry(consumer_data.stream_ht->ht, &iter.iter, node, |
| 864 | node) { |
| 865 | struct lttng_consumer_stream *stream = |
| 866 | caa_container_of(node, struct lttng_consumer_stream, node); |
| 867 | consumer_del_stream(stream); |
| 868 | } |
| 869 | |
| 870 | cds_lfht_for_each_entry(consumer_data.channel_ht->ht, &iter.iter, node, |
| 871 | node) { |
| 872 | struct lttng_consumer_channel *channel = |
| 873 | caa_container_of(node, struct lttng_consumer_channel, node); |
| 874 | consumer_del_channel(channel); |
| 875 | } |
| 876 | |
| 877 | rcu_read_unlock(); |
| 878 | |
| 879 | lttng_ht_destroy(consumer_data.stream_ht); |
| 880 | lttng_ht_destroy(consumer_data.channel_ht); |
| 881 | } |
| 882 | |
| 883 | /* |
| 884 | * Called from signal handler. |
| 885 | */ |
| 886 | void lttng_consumer_should_exit(struct lttng_consumer_local_data *ctx) |
| 887 | { |
| 888 | int ret; |
| 889 | consumer_quit = 1; |
| 890 | do { |
| 891 | ret = write(ctx->consumer_should_quit[1], "4", 1); |
| 892 | } while (ret < 0 && errno == EINTR); |
| 893 | if (ret < 0) { |
| 894 | perror("write consumer quit"); |
| 895 | } |
| 896 | } |
| 897 | |
| 898 | void lttng_consumer_sync_trace_file(struct lttng_consumer_stream *stream, |
| 899 | off_t orig_offset) |
| 900 | { |
| 901 | int outfd = stream->out_fd; |
| 902 | |
| 903 | /* |
| 904 | * This does a blocking write-and-wait on any page that belongs to the |
| 905 | * subbuffer prior to the one we just wrote. |
| 906 | * Don't care about error values, as these are just hints and ways to |
| 907 | * limit the amount of page cache used. |
| 908 | */ |
| 909 | if (orig_offset < stream->chan->max_sb_size) { |
| 910 | return; |
| 911 | } |
| 912 | lttng_sync_file_range(outfd, orig_offset - stream->chan->max_sb_size, |
| 913 | stream->chan->max_sb_size, |
| 914 | SYNC_FILE_RANGE_WAIT_BEFORE |
| 915 | | SYNC_FILE_RANGE_WRITE |
| 916 | | SYNC_FILE_RANGE_WAIT_AFTER); |
| 917 | /* |
| 918 | * Give hints to the kernel about how we access the file: |
| 919 | * POSIX_FADV_DONTNEED : we won't re-access data in a near future after |
| 920 | * we write it. |
| 921 | * |
| 922 | * We need to call fadvise again after the file grows because the |
| 923 | * kernel does not seem to apply fadvise to non-existing parts of the |
| 924 | * file. |
| 925 | * |
| 926 | * Call fadvise _after_ having waited for the page writeback to |
| 927 | * complete because the dirty page writeback semantic is not well |
| 928 | * defined. So it can be expected to lead to lower throughput in |
| 929 | * streaming. |
| 930 | */ |
| 931 | posix_fadvise(outfd, orig_offset - stream->chan->max_sb_size, |
| 932 | stream->chan->max_sb_size, POSIX_FADV_DONTNEED); |
| 933 | } |
| 934 | |
| 935 | /* |
| 936 | * Initialise the necessary environnement : |
| 937 | * - create a new context |
| 938 | * - create the poll_pipe |
| 939 | * - create the should_quit pipe (for signal handler) |
| 940 | * - create the thread pipe (for splice) |
| 941 | * |
| 942 | * Takes a function pointer as argument, this function is called when data is |
| 943 | * available on a buffer. This function is responsible to do the |
| 944 | * kernctl_get_next_subbuf, read the data with mmap or splice depending on the |
| 945 | * buffer configuration and then kernctl_put_next_subbuf at the end. |
| 946 | * |
| 947 | * Returns a pointer to the new context or NULL on error. |
| 948 | */ |
| 949 | struct lttng_consumer_local_data *lttng_consumer_create( |
| 950 | enum lttng_consumer_type type, |
| 951 | ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream, |
| 952 | struct lttng_consumer_local_data *ctx), |
| 953 | int (*recv_channel)(struct lttng_consumer_channel *channel), |
| 954 | int (*recv_stream)(struct lttng_consumer_stream *stream), |
| 955 | int (*update_stream)(int stream_key, uint32_t state)) |
| 956 | { |
| 957 | int ret, i; |
| 958 | struct lttng_consumer_local_data *ctx; |
| 959 | |
| 960 | assert(consumer_data.type == LTTNG_CONSUMER_UNKNOWN || |
| 961 | consumer_data.type == type); |
| 962 | consumer_data.type = type; |
| 963 | |
| 964 | ctx = zmalloc(sizeof(struct lttng_consumer_local_data)); |
| 965 | if (ctx == NULL) { |
| 966 | perror("allocating context"); |
| 967 | goto error; |
| 968 | } |
| 969 | |
| 970 | ctx->consumer_error_socket = -1; |
| 971 | /* assign the callbacks */ |
| 972 | ctx->on_buffer_ready = buffer_ready; |
| 973 | ctx->on_recv_channel = recv_channel; |
| 974 | ctx->on_recv_stream = recv_stream; |
| 975 | ctx->on_update_stream = update_stream; |
| 976 | |
| 977 | ret = pipe(ctx->consumer_poll_pipe); |
| 978 | if (ret < 0) { |
| 979 | perror("Error creating poll pipe"); |
| 980 | goto error_poll_pipe; |
| 981 | } |
| 982 | |
| 983 | /* set read end of the pipe to non-blocking */ |
| 984 | ret = fcntl(ctx->consumer_poll_pipe[0], F_SETFL, O_NONBLOCK); |
| 985 | if (ret < 0) { |
| 986 | perror("fcntl O_NONBLOCK"); |
| 987 | goto error_poll_fcntl; |
| 988 | } |
| 989 | |
| 990 | /* set write end of the pipe to non-blocking */ |
| 991 | ret = fcntl(ctx->consumer_poll_pipe[1], F_SETFL, O_NONBLOCK); |
| 992 | if (ret < 0) { |
| 993 | perror("fcntl O_NONBLOCK"); |
| 994 | goto error_poll_fcntl; |
| 995 | } |
| 996 | |
| 997 | ret = pipe(ctx->consumer_should_quit); |
| 998 | if (ret < 0) { |
| 999 | perror("Error creating recv pipe"); |
| 1000 | goto error_quit_pipe; |
| 1001 | } |
| 1002 | |
| 1003 | ret = pipe(ctx->consumer_thread_pipe); |
| 1004 | if (ret < 0) { |
| 1005 | perror("Error creating thread pipe"); |
| 1006 | goto error_thread_pipe; |
| 1007 | } |
| 1008 | |
| 1009 | return ctx; |
| 1010 | |
| 1011 | |
| 1012 | error_thread_pipe: |
| 1013 | for (i = 0; i < 2; i++) { |
| 1014 | int err; |
| 1015 | |
| 1016 | err = close(ctx->consumer_should_quit[i]); |
| 1017 | if (err) { |
| 1018 | PERROR("close"); |
| 1019 | } |
| 1020 | } |
| 1021 | error_poll_fcntl: |
| 1022 | error_quit_pipe: |
| 1023 | for (i = 0; i < 2; i++) { |
| 1024 | int err; |
| 1025 | |
| 1026 | err = close(ctx->consumer_poll_pipe[i]); |
| 1027 | if (err) { |
| 1028 | PERROR("close"); |
| 1029 | } |
| 1030 | } |
| 1031 | error_poll_pipe: |
| 1032 | free(ctx); |
| 1033 | error: |
| 1034 | return NULL; |
| 1035 | } |
| 1036 | |
| 1037 | /* |
| 1038 | * Close all fds associated with the instance and free the context. |
| 1039 | */ |
| 1040 | void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx) |
| 1041 | { |
| 1042 | int ret; |
| 1043 | |
| 1044 | ret = close(ctx->consumer_error_socket); |
| 1045 | if (ret) { |
| 1046 | PERROR("close"); |
| 1047 | } |
| 1048 | ret = close(ctx->consumer_thread_pipe[0]); |
| 1049 | if (ret) { |
| 1050 | PERROR("close"); |
| 1051 | } |
| 1052 | ret = close(ctx->consumer_thread_pipe[1]); |
| 1053 | if (ret) { |
| 1054 | PERROR("close"); |
| 1055 | } |
| 1056 | ret = close(ctx->consumer_poll_pipe[0]); |
| 1057 | if (ret) { |
| 1058 | PERROR("close"); |
| 1059 | } |
| 1060 | ret = close(ctx->consumer_poll_pipe[1]); |
| 1061 | if (ret) { |
| 1062 | PERROR("close"); |
| 1063 | } |
| 1064 | ret = close(ctx->consumer_should_quit[0]); |
| 1065 | if (ret) { |
| 1066 | PERROR("close"); |
| 1067 | } |
| 1068 | ret = close(ctx->consumer_should_quit[1]); |
| 1069 | if (ret) { |
| 1070 | PERROR("close"); |
| 1071 | } |
| 1072 | unlink(ctx->consumer_command_sock_path); |
| 1073 | free(ctx); |
| 1074 | } |
| 1075 | |
| 1076 | /* |
| 1077 | * Write the metadata stream id on the specified file descriptor. |
| 1078 | */ |
| 1079 | static int write_relayd_metadata_id(int fd, |
| 1080 | struct lttng_consumer_stream *stream, |
| 1081 | struct consumer_relayd_sock_pair *relayd) |
| 1082 | { |
| 1083 | int ret; |
| 1084 | uint64_t metadata_id; |
| 1085 | |
| 1086 | metadata_id = htobe64(stream->relayd_stream_id); |
| 1087 | do { |
| 1088 | ret = write(fd, (void *) &metadata_id, |
| 1089 | sizeof(stream->relayd_stream_id)); |
| 1090 | } while (ret < 0 && errno == EINTR); |
| 1091 | if (ret < 0) { |
| 1092 | PERROR("write metadata stream id"); |
| 1093 | goto end; |
| 1094 | } |
| 1095 | DBG("Metadata stream id %" PRIu64 " written before data", |
| 1096 | stream->relayd_stream_id); |
| 1097 | |
| 1098 | end: |
| 1099 | return ret; |
| 1100 | } |
| 1101 | |
| 1102 | /* |
| 1103 | * Mmap the ring buffer, read it and write the data to the tracefile. This is a |
| 1104 | * core function for writing trace buffers to either the local filesystem or |
| 1105 | * the network. |
| 1106 | * |
| 1107 | * Careful review MUST be put if any changes occur! |
| 1108 | * |
| 1109 | * Returns the number of bytes written |
| 1110 | */ |
| 1111 | ssize_t lttng_consumer_on_read_subbuffer_mmap( |
| 1112 | struct lttng_consumer_local_data *ctx, |
| 1113 | struct lttng_consumer_stream *stream, unsigned long len) |
| 1114 | { |
| 1115 | unsigned long mmap_offset; |
| 1116 | ssize_t ret = 0, written = 0; |
| 1117 | off_t orig_offset = stream->out_fd_offset; |
| 1118 | /* Default is on the disk */ |
| 1119 | int outfd = stream->out_fd; |
| 1120 | struct consumer_relayd_sock_pair *relayd = NULL; |
| 1121 | |
| 1122 | /* RCU lock for the relayd pointer */ |
| 1123 | rcu_read_lock(); |
| 1124 | |
| 1125 | /* Flag that the current stream if set for network streaming. */ |
| 1126 | if (stream->net_seq_idx != -1) { |
| 1127 | relayd = consumer_find_relayd(stream->net_seq_idx); |
| 1128 | if (relayd == NULL) { |
| 1129 | goto end; |
| 1130 | } |
| 1131 | } |
| 1132 | |
| 1133 | /* get the offset inside the fd to mmap */ |
| 1134 | switch (consumer_data.type) { |
| 1135 | case LTTNG_CONSUMER_KERNEL: |
| 1136 | ret = kernctl_get_mmap_read_offset(stream->wait_fd, &mmap_offset); |
| 1137 | break; |
| 1138 | case LTTNG_CONSUMER32_UST: |
| 1139 | case LTTNG_CONSUMER64_UST: |
| 1140 | ret = lttng_ustctl_get_mmap_read_offset(stream->chan->handle, |
| 1141 | stream->buf, &mmap_offset); |
| 1142 | break; |
| 1143 | default: |
| 1144 | ERR("Unknown consumer_data type"); |
| 1145 | assert(0); |
| 1146 | } |
| 1147 | if (ret != 0) { |
| 1148 | errno = -ret; |
| 1149 | PERROR("tracer ctl get_mmap_read_offset"); |
| 1150 | written = ret; |
| 1151 | goto end; |
| 1152 | } |
| 1153 | |
| 1154 | /* Handle stream on the relayd if the output is on the network */ |
| 1155 | if (relayd) { |
| 1156 | unsigned long netlen = len; |
| 1157 | |
| 1158 | /* |
| 1159 | * Lock the control socket for the complete duration of the function |
| 1160 | * since from this point on we will use the socket. |
| 1161 | */ |
| 1162 | if (stream->metadata_flag) { |
| 1163 | /* Metadata requires the control socket. */ |
| 1164 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); |
| 1165 | netlen += sizeof(stream->relayd_stream_id); |
| 1166 | } |
| 1167 | |
| 1168 | ret = write_relayd_stream_header(stream, netlen, relayd); |
| 1169 | if (ret >= 0) { |
| 1170 | /* Use the returned socket. */ |
| 1171 | outfd = ret; |
| 1172 | |
| 1173 | /* Write metadata stream id before payload */ |
| 1174 | if (stream->metadata_flag) { |
| 1175 | ret = write_relayd_metadata_id(outfd, stream, relayd); |
| 1176 | if (ret < 0) { |
| 1177 | written = ret; |
| 1178 | goto end; |
| 1179 | } |
| 1180 | } |
| 1181 | } |
| 1182 | /* Else, use the default set before which is the filesystem. */ |
| 1183 | } |
| 1184 | |
| 1185 | while (len > 0) { |
| 1186 | do { |
| 1187 | ret = write(outfd, stream->mmap_base + mmap_offset, len); |
| 1188 | } while (ret < 0 && errno == EINTR); |
| 1189 | if (ret < 0) { |
| 1190 | PERROR("Error in file write"); |
| 1191 | if (written == 0) { |
| 1192 | written = ret; |
| 1193 | } |
| 1194 | goto end; |
| 1195 | } else if (ret > len) { |
| 1196 | PERROR("Error in file write (ret %zd > len %lu)", ret, len); |
| 1197 | written += ret; |
| 1198 | goto end; |
| 1199 | } else { |
| 1200 | len -= ret; |
| 1201 | mmap_offset += ret; |
| 1202 | } |
| 1203 | DBG("Consumer mmap write() ret %zd (len %lu)", ret, len); |
| 1204 | |
| 1205 | /* This call is useless on a socket so better save a syscall. */ |
| 1206 | if (!relayd) { |
| 1207 | /* This won't block, but will start writeout asynchronously */ |
| 1208 | lttng_sync_file_range(outfd, stream->out_fd_offset, ret, |
| 1209 | SYNC_FILE_RANGE_WRITE); |
| 1210 | stream->out_fd_offset += ret; |
| 1211 | } |
| 1212 | written += ret; |
| 1213 | } |
| 1214 | lttng_consumer_sync_trace_file(stream, orig_offset); |
| 1215 | |
| 1216 | end: |
| 1217 | /* Unlock only if ctrl socket used */ |
| 1218 | if (relayd && stream->metadata_flag) { |
| 1219 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); |
| 1220 | } |
| 1221 | |
| 1222 | rcu_read_unlock(); |
| 1223 | return written; |
| 1224 | } |
| 1225 | |
| 1226 | /* |
| 1227 | * Splice the data from the ring buffer to the tracefile. |
| 1228 | * |
| 1229 | * Returns the number of bytes spliced. |
| 1230 | */ |
| 1231 | ssize_t lttng_consumer_on_read_subbuffer_splice( |
| 1232 | struct lttng_consumer_local_data *ctx, |
| 1233 | struct lttng_consumer_stream *stream, unsigned long len) |
| 1234 | { |
| 1235 | ssize_t ret = 0, written = 0, ret_splice = 0; |
| 1236 | loff_t offset = 0; |
| 1237 | off_t orig_offset = stream->out_fd_offset; |
| 1238 | int fd = stream->wait_fd; |
| 1239 | /* Default is on the disk */ |
| 1240 | int outfd = stream->out_fd; |
| 1241 | struct consumer_relayd_sock_pair *relayd = NULL; |
| 1242 | |
| 1243 | switch (consumer_data.type) { |
| 1244 | case LTTNG_CONSUMER_KERNEL: |
| 1245 | break; |
| 1246 | case LTTNG_CONSUMER32_UST: |
| 1247 | case LTTNG_CONSUMER64_UST: |
| 1248 | /* Not supported for user space tracing */ |
| 1249 | return -ENOSYS; |
| 1250 | default: |
| 1251 | ERR("Unknown consumer_data type"); |
| 1252 | assert(0); |
| 1253 | } |
| 1254 | |
| 1255 | /* RCU lock for the relayd pointer */ |
| 1256 | rcu_read_lock(); |
| 1257 | |
| 1258 | /* Flag that the current stream if set for network streaming. */ |
| 1259 | if (stream->net_seq_idx != -1) { |
| 1260 | relayd = consumer_find_relayd(stream->net_seq_idx); |
| 1261 | if (relayd == NULL) { |
| 1262 | goto end; |
| 1263 | } |
| 1264 | } |
| 1265 | |
| 1266 | /* Write metadata stream id before payload */ |
| 1267 | if (stream->metadata_flag && relayd) { |
| 1268 | /* |
| 1269 | * Lock the control socket for the complete duration of the function |
| 1270 | * since from this point on we will use the socket. |
| 1271 | */ |
| 1272 | pthread_mutex_lock(&relayd->ctrl_sock_mutex); |
| 1273 | |
| 1274 | ret = write_relayd_metadata_id(ctx->consumer_thread_pipe[1], |
| 1275 | stream, relayd); |
| 1276 | if (ret < 0) { |
| 1277 | written = ret; |
| 1278 | goto end; |
| 1279 | } |
| 1280 | } |
| 1281 | |
| 1282 | while (len > 0) { |
| 1283 | DBG("splice chan to pipe offset %lu of len %lu (fd : %d)", |
| 1284 | (unsigned long)offset, len, fd); |
| 1285 | ret_splice = splice(fd, &offset, ctx->consumer_thread_pipe[1], NULL, len, |
| 1286 | SPLICE_F_MOVE | SPLICE_F_MORE); |
| 1287 | DBG("splice chan to pipe, ret %zd", ret_splice); |
| 1288 | if (ret_splice < 0) { |
| 1289 | PERROR("Error in relay splice"); |
| 1290 | if (written == 0) { |
| 1291 | written = ret_splice; |
| 1292 | } |
| 1293 | ret = errno; |
| 1294 | goto splice_error; |
| 1295 | } |
| 1296 | |
| 1297 | /* Handle stream on the relayd if the output is on the network */ |
| 1298 | if (relayd) { |
| 1299 | if (stream->metadata_flag) { |
| 1300 | /* Update counter to fit the spliced data */ |
| 1301 | ret_splice += sizeof(stream->relayd_stream_id); |
| 1302 | len += sizeof(stream->relayd_stream_id); |
| 1303 | /* |
| 1304 | * We do this so the return value can match the len passed as |
| 1305 | * argument to this function. |
| 1306 | */ |
| 1307 | written -= sizeof(stream->relayd_stream_id); |
| 1308 | } |
| 1309 | |
| 1310 | ret = write_relayd_stream_header(stream, ret_splice, relayd); |
| 1311 | if (ret >= 0) { |
| 1312 | /* Use the returned socket. */ |
| 1313 | outfd = ret; |
| 1314 | } else { |
| 1315 | ERR("Remote relayd disconnected. Stopping"); |
| 1316 | goto end; |
| 1317 | } |
| 1318 | } |
| 1319 | |
| 1320 | /* Splice data out */ |
| 1321 | ret_splice = splice(ctx->consumer_thread_pipe[0], NULL, outfd, NULL, |
| 1322 | ret_splice, SPLICE_F_MOVE | SPLICE_F_MORE); |
| 1323 | DBG("Kernel consumer splice pipe to file, ret %zd", ret_splice); |
| 1324 | if (ret_splice < 0) { |
| 1325 | PERROR("Error in file splice"); |
| 1326 | if (written == 0) { |
| 1327 | written = ret_splice; |
| 1328 | } |
| 1329 | ret = errno; |
| 1330 | goto splice_error; |
| 1331 | } else if (ret_splice > len) { |
| 1332 | errno = EINVAL; |
| 1333 | PERROR("Wrote more data than requested %zd (len: %lu)", |
| 1334 | ret_splice, len); |
| 1335 | written += ret_splice; |
| 1336 | ret = errno; |
| 1337 | goto splice_error; |
| 1338 | } |
| 1339 | len -= ret_splice; |
| 1340 | |
| 1341 | /* This call is useless on a socket so better save a syscall. */ |
| 1342 | if (!relayd) { |
| 1343 | /* This won't block, but will start writeout asynchronously */ |
| 1344 | lttng_sync_file_range(outfd, stream->out_fd_offset, ret_splice, |
| 1345 | SYNC_FILE_RANGE_WRITE); |
| 1346 | stream->out_fd_offset += ret_splice; |
| 1347 | } |
| 1348 | written += ret_splice; |
| 1349 | } |
| 1350 | lttng_consumer_sync_trace_file(stream, orig_offset); |
| 1351 | |
| 1352 | ret = ret_splice; |
| 1353 | |
| 1354 | goto end; |
| 1355 | |
| 1356 | splice_error: |
| 1357 | /* send the appropriate error description to sessiond */ |
| 1358 | switch (ret) { |
| 1359 | case EBADF: |
| 1360 | lttng_consumer_send_error(ctx, CONSUMERD_SPLICE_EBADF); |
| 1361 | break; |
| 1362 | case EINVAL: |
| 1363 | lttng_consumer_send_error(ctx, CONSUMERD_SPLICE_EINVAL); |
| 1364 | break; |
| 1365 | case ENOMEM: |
| 1366 | lttng_consumer_send_error(ctx, CONSUMERD_SPLICE_ENOMEM); |
| 1367 | break; |
| 1368 | case ESPIPE: |
| 1369 | lttng_consumer_send_error(ctx, CONSUMERD_SPLICE_ESPIPE); |
| 1370 | break; |
| 1371 | } |
| 1372 | |
| 1373 | end: |
| 1374 | if (relayd && stream->metadata_flag) { |
| 1375 | pthread_mutex_unlock(&relayd->ctrl_sock_mutex); |
| 1376 | } |
| 1377 | |
| 1378 | rcu_read_unlock(); |
| 1379 | return written; |
| 1380 | } |
| 1381 | |
| 1382 | /* |
| 1383 | * Take a snapshot for a specific fd |
| 1384 | * |
| 1385 | * Returns 0 on success, < 0 on error |
| 1386 | */ |
| 1387 | int lttng_consumer_take_snapshot(struct lttng_consumer_local_data *ctx, |
| 1388 | struct lttng_consumer_stream *stream) |
| 1389 | { |
| 1390 | switch (consumer_data.type) { |
| 1391 | case LTTNG_CONSUMER_KERNEL: |
| 1392 | return lttng_kconsumer_take_snapshot(ctx, stream); |
| 1393 | case LTTNG_CONSUMER32_UST: |
| 1394 | case LTTNG_CONSUMER64_UST: |
| 1395 | return lttng_ustconsumer_take_snapshot(ctx, stream); |
| 1396 | default: |
| 1397 | ERR("Unknown consumer_data type"); |
| 1398 | assert(0); |
| 1399 | return -ENOSYS; |
| 1400 | } |
| 1401 | |
| 1402 | } |
| 1403 | |
| 1404 | /* |
| 1405 | * Get the produced position |
| 1406 | * |
| 1407 | * Returns 0 on success, < 0 on error |
| 1408 | */ |
| 1409 | int lttng_consumer_get_produced_snapshot( |
| 1410 | struct lttng_consumer_local_data *ctx, |
| 1411 | struct lttng_consumer_stream *stream, |
| 1412 | unsigned long *pos) |
| 1413 | { |
| 1414 | switch (consumer_data.type) { |
| 1415 | case LTTNG_CONSUMER_KERNEL: |
| 1416 | return lttng_kconsumer_get_produced_snapshot(ctx, stream, pos); |
| 1417 | case LTTNG_CONSUMER32_UST: |
| 1418 | case LTTNG_CONSUMER64_UST: |
| 1419 | return lttng_ustconsumer_get_produced_snapshot(ctx, stream, pos); |
| 1420 | default: |
| 1421 | ERR("Unknown consumer_data type"); |
| 1422 | assert(0); |
| 1423 | return -ENOSYS; |
| 1424 | } |
| 1425 | } |
| 1426 | |
| 1427 | int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx, |
| 1428 | int sock, struct pollfd *consumer_sockpoll) |
| 1429 | { |
| 1430 | switch (consumer_data.type) { |
| 1431 | case LTTNG_CONSUMER_KERNEL: |
| 1432 | return lttng_kconsumer_recv_cmd(ctx, sock, consumer_sockpoll); |
| 1433 | case LTTNG_CONSUMER32_UST: |
| 1434 | case LTTNG_CONSUMER64_UST: |
| 1435 | return lttng_ustconsumer_recv_cmd(ctx, sock, consumer_sockpoll); |
| 1436 | default: |
| 1437 | ERR("Unknown consumer_data type"); |
| 1438 | assert(0); |
| 1439 | return -ENOSYS; |
| 1440 | } |
| 1441 | } |
| 1442 | |
| 1443 | /* |
| 1444 | * This thread polls the fds in the set to consume the data and write |
| 1445 | * it to tracefile if necessary. |
| 1446 | */ |
| 1447 | void *lttng_consumer_thread_poll_fds(void *data) |
| 1448 | { |
| 1449 | int num_rdy, num_hup, high_prio, ret, i; |
| 1450 | struct pollfd *pollfd = NULL; |
| 1451 | /* local view of the streams */ |
| 1452 | struct lttng_consumer_stream **local_stream = NULL; |
| 1453 | /* local view of consumer_data.fds_count */ |
| 1454 | int nb_fd = 0; |
| 1455 | struct lttng_consumer_local_data *ctx = data; |
| 1456 | struct lttng_ht *metadata_ht; |
| 1457 | struct lttng_ht_iter iter; |
| 1458 | struct lttng_ht_node_ulong *node; |
| 1459 | struct lttng_consumer_stream *metadata_stream; |
| 1460 | ssize_t len; |
| 1461 | |
| 1462 | metadata_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); |
| 1463 | |
| 1464 | rcu_register_thread(); |
| 1465 | |
| 1466 | local_stream = zmalloc(sizeof(struct lttng_consumer_stream)); |
| 1467 | |
| 1468 | while (1) { |
| 1469 | high_prio = 0; |
| 1470 | num_hup = 0; |
| 1471 | |
| 1472 | /* |
| 1473 | * the fds set has been updated, we need to update our |
| 1474 | * local array as well |
| 1475 | */ |
| 1476 | pthread_mutex_lock(&consumer_data.lock); |
| 1477 | if (consumer_data.need_update) { |
| 1478 | if (pollfd != NULL) { |
| 1479 | free(pollfd); |
| 1480 | pollfd = NULL; |
| 1481 | } |
| 1482 | if (local_stream != NULL) { |
| 1483 | free(local_stream); |
| 1484 | local_stream = NULL; |
| 1485 | } |
| 1486 | |
| 1487 | /* allocate for all fds + 1 for the consumer_poll_pipe */ |
| 1488 | pollfd = zmalloc((consumer_data.stream_count + 1) * sizeof(struct pollfd)); |
| 1489 | if (pollfd == NULL) { |
| 1490 | perror("pollfd malloc"); |
| 1491 | pthread_mutex_unlock(&consumer_data.lock); |
| 1492 | goto end; |
| 1493 | } |
| 1494 | |
| 1495 | /* allocate for all fds + 1 for the consumer_poll_pipe */ |
| 1496 | local_stream = zmalloc((consumer_data.stream_count + 1) * |
| 1497 | sizeof(struct lttng_consumer_stream)); |
| 1498 | if (local_stream == NULL) { |
| 1499 | perror("local_stream malloc"); |
| 1500 | pthread_mutex_unlock(&consumer_data.lock); |
| 1501 | goto end; |
| 1502 | } |
| 1503 | ret = consumer_update_poll_array(ctx, &pollfd, local_stream, |
| 1504 | metadata_ht); |
| 1505 | if (ret < 0) { |
| 1506 | ERR("Error in allocating pollfd or local_outfds"); |
| 1507 | lttng_consumer_send_error(ctx, CONSUMERD_POLL_ERROR); |
| 1508 | pthread_mutex_unlock(&consumer_data.lock); |
| 1509 | goto end; |
| 1510 | } |
| 1511 | nb_fd = ret; |
| 1512 | consumer_data.need_update = 0; |
| 1513 | } |
| 1514 | pthread_mutex_unlock(&consumer_data.lock); |
| 1515 | |
| 1516 | /* No FDs and consumer_quit, consumer_cleanup the thread */ |
| 1517 | if (nb_fd == 0 && consumer_quit == 1) { |
| 1518 | goto end; |
| 1519 | } |
| 1520 | /* poll on the array of fds */ |
| 1521 | restart: |
| 1522 | DBG("polling on %d fd", nb_fd + 1); |
| 1523 | num_rdy = poll(pollfd, nb_fd + 1, consumer_poll_timeout); |
| 1524 | DBG("poll num_rdy : %d", num_rdy); |
| 1525 | if (num_rdy == -1) { |
| 1526 | /* |
| 1527 | * Restart interrupted system call. |
| 1528 | */ |
| 1529 | if (errno == EINTR) { |
| 1530 | goto restart; |
| 1531 | } |
| 1532 | perror("Poll error"); |
| 1533 | lttng_consumer_send_error(ctx, CONSUMERD_POLL_ERROR); |
| 1534 | goto end; |
| 1535 | } else if (num_rdy == 0) { |
| 1536 | DBG("Polling thread timed out"); |
| 1537 | goto end; |
| 1538 | } |
| 1539 | |
| 1540 | /* |
| 1541 | * If the consumer_poll_pipe triggered poll go directly to the |
| 1542 | * beginning of the loop to update the array. We want to prioritize |
| 1543 | * array update over low-priority reads. |
| 1544 | */ |
| 1545 | if (pollfd[nb_fd].revents & (POLLIN | POLLPRI)) { |
| 1546 | size_t pipe_readlen; |
| 1547 | char tmp; |
| 1548 | |
| 1549 | DBG("consumer_poll_pipe wake up"); |
| 1550 | /* Consume 1 byte of pipe data */ |
| 1551 | do { |
| 1552 | pipe_readlen = read(ctx->consumer_poll_pipe[0], &tmp, 1); |
| 1553 | } while (pipe_readlen == -1 && errno == EINTR); |
| 1554 | continue; |
| 1555 | } |
| 1556 | |
| 1557 | /* Take care of high priority channels first. */ |
| 1558 | for (i = 0; i < nb_fd; i++) { |
| 1559 | /* Lookup for metadata which is the highest priority */ |
| 1560 | lttng_ht_lookup(metadata_ht, |
| 1561 | (void *)((unsigned long) pollfd[i].fd), &iter); |
| 1562 | node = lttng_ht_iter_get_node_ulong(&iter); |
| 1563 | if (node != NULL && |
| 1564 | (pollfd[i].revents & (POLLIN | POLLPRI))) { |
| 1565 | DBG("Urgent metadata read on fd %d", pollfd[i].fd); |
| 1566 | metadata_stream = caa_container_of(node, |
| 1567 | struct lttng_consumer_stream, waitfd_node); |
| 1568 | high_prio = 1; |
| 1569 | len = ctx->on_buffer_ready(metadata_stream, ctx); |
| 1570 | /* it's ok to have an unavailable sub-buffer */ |
| 1571 | if (len < 0 && len != -EAGAIN) { |
| 1572 | goto end; |
| 1573 | } else if (len > 0) { |
| 1574 | metadata_stream->data_read = 1; |
| 1575 | } |
| 1576 | } else if (pollfd[i].revents & POLLPRI) { |
| 1577 | DBG("Urgent read on fd %d", pollfd[i].fd); |
| 1578 | high_prio = 1; |
| 1579 | len = ctx->on_buffer_ready(local_stream[i], ctx); |
| 1580 | /* it's ok to have an unavailable sub-buffer */ |
| 1581 | if (len < 0 && len != -EAGAIN) { |
| 1582 | goto end; |
| 1583 | } else if (len > 0) { |
| 1584 | local_stream[i]->data_read = 1; |
| 1585 | } |
| 1586 | } |
| 1587 | } |
| 1588 | |
| 1589 | /* |
| 1590 | * If we read high prio channel in this loop, try again |
| 1591 | * for more high prio data. |
| 1592 | */ |
| 1593 | if (high_prio) { |
| 1594 | continue; |
| 1595 | } |
| 1596 | |
| 1597 | /* Take care of low priority channels. */ |
| 1598 | for (i = 0; i < nb_fd; i++) { |
| 1599 | if ((pollfd[i].revents & POLLIN) || |
| 1600 | local_stream[i]->hangup_flush_done) { |
| 1601 | DBG("Normal read on fd %d", pollfd[i].fd); |
| 1602 | len = ctx->on_buffer_ready(local_stream[i], ctx); |
| 1603 | /* it's ok to have an unavailable sub-buffer */ |
| 1604 | if (len < 0 && len != -EAGAIN) { |
| 1605 | goto end; |
| 1606 | } else if (len > 0) { |
| 1607 | local_stream[i]->data_read = 1; |
| 1608 | } |
| 1609 | } |
| 1610 | } |
| 1611 | |
| 1612 | /* Handle hangup and errors */ |
| 1613 | for (i = 0; i < nb_fd; i++) { |
| 1614 | if (!local_stream[i]->hangup_flush_done |
| 1615 | && (pollfd[i].revents & (POLLHUP | POLLERR | POLLNVAL)) |
| 1616 | && (consumer_data.type == LTTNG_CONSUMER32_UST |
| 1617 | || consumer_data.type == LTTNG_CONSUMER64_UST)) { |
| 1618 | DBG("fd %d is hup|err|nval. Attempting flush and read.", |
| 1619 | pollfd[i].fd); |
| 1620 | lttng_ustconsumer_on_stream_hangup(local_stream[i]); |
| 1621 | /* Attempt read again, for the data we just flushed. */ |
| 1622 | local_stream[i]->data_read = 1; |
| 1623 | } |
| 1624 | /* |
| 1625 | * If the poll flag is HUP/ERR/NVAL and we have |
| 1626 | * read no data in this pass, we can remove the |
| 1627 | * stream from its hash table. |
| 1628 | */ |
| 1629 | if ((pollfd[i].revents & POLLHUP)) { |
| 1630 | DBG("Polling fd %d tells it has hung up.", pollfd[i].fd); |
| 1631 | if (!local_stream[i]->data_read) { |
| 1632 | if (local_stream[i]->metadata_flag) { |
| 1633 | iter.iter.node = &local_stream[i]->waitfd_node.node; |
| 1634 | ret = lttng_ht_del(metadata_ht, &iter); |
| 1635 | assert(!ret); |
| 1636 | } |
| 1637 | consumer_del_stream(local_stream[i]); |
| 1638 | num_hup++; |
| 1639 | } |
| 1640 | } else if (pollfd[i].revents & POLLERR) { |
| 1641 | ERR("Error returned in polling fd %d.", pollfd[i].fd); |
| 1642 | if (!local_stream[i]->data_read) { |
| 1643 | if (local_stream[i]->metadata_flag) { |
| 1644 | iter.iter.node = &local_stream[i]->waitfd_node.node; |
| 1645 | ret = lttng_ht_del(metadata_ht, &iter); |
| 1646 | assert(!ret); |
| 1647 | } |
| 1648 | consumer_del_stream(local_stream[i]); |
| 1649 | num_hup++; |
| 1650 | } |
| 1651 | } else if (pollfd[i].revents & POLLNVAL) { |
| 1652 | ERR("Polling fd %d tells fd is not open.", pollfd[i].fd); |
| 1653 | if (!local_stream[i]->data_read) { |
| 1654 | if (local_stream[i]->metadata_flag) { |
| 1655 | iter.iter.node = &local_stream[i]->waitfd_node.node; |
| 1656 | ret = lttng_ht_del(metadata_ht, &iter); |
| 1657 | assert(!ret); |
| 1658 | } |
| 1659 | consumer_del_stream(local_stream[i]); |
| 1660 | num_hup++; |
| 1661 | } |
| 1662 | } |
| 1663 | local_stream[i]->data_read = 0; |
| 1664 | } |
| 1665 | } |
| 1666 | end: |
| 1667 | DBG("polling thread exiting"); |
| 1668 | if (pollfd != NULL) { |
| 1669 | free(pollfd); |
| 1670 | pollfd = NULL; |
| 1671 | } |
| 1672 | if (local_stream != NULL) { |
| 1673 | free(local_stream); |
| 1674 | local_stream = NULL; |
| 1675 | } |
| 1676 | rcu_unregister_thread(); |
| 1677 | return NULL; |
| 1678 | } |
| 1679 | |
| 1680 | /* |
| 1681 | * This thread listens on the consumerd socket and receives the file |
| 1682 | * descriptors from the session daemon. |
| 1683 | */ |
| 1684 | void *lttng_consumer_thread_receive_fds(void *data) |
| 1685 | { |
| 1686 | int sock, client_socket, ret; |
| 1687 | /* |
| 1688 | * structure to poll for incoming data on communication socket avoids |
| 1689 | * making blocking sockets. |
| 1690 | */ |
| 1691 | struct pollfd consumer_sockpoll[2]; |
| 1692 | struct lttng_consumer_local_data *ctx = data; |
| 1693 | |
| 1694 | rcu_register_thread(); |
| 1695 | |
| 1696 | DBG("Creating command socket %s", ctx->consumer_command_sock_path); |
| 1697 | unlink(ctx->consumer_command_sock_path); |
| 1698 | client_socket = lttcomm_create_unix_sock(ctx->consumer_command_sock_path); |
| 1699 | if (client_socket < 0) { |
| 1700 | ERR("Cannot create command socket"); |
| 1701 | goto end; |
| 1702 | } |
| 1703 | |
| 1704 | ret = lttcomm_listen_unix_sock(client_socket); |
| 1705 | if (ret < 0) { |
| 1706 | goto end; |
| 1707 | } |
| 1708 | |
| 1709 | DBG("Sending ready command to lttng-sessiond"); |
| 1710 | ret = lttng_consumer_send_error(ctx, CONSUMERD_COMMAND_SOCK_READY); |
| 1711 | /* return < 0 on error, but == 0 is not fatal */ |
| 1712 | if (ret < 0) { |
| 1713 | ERR("Error sending ready command to lttng-sessiond"); |
| 1714 | goto end; |
| 1715 | } |
| 1716 | |
| 1717 | ret = fcntl(client_socket, F_SETFL, O_NONBLOCK); |
| 1718 | if (ret < 0) { |
| 1719 | perror("fcntl O_NONBLOCK"); |
| 1720 | goto end; |
| 1721 | } |
| 1722 | |
| 1723 | /* prepare the FDs to poll : to client socket and the should_quit pipe */ |
| 1724 | consumer_sockpoll[0].fd = ctx->consumer_should_quit[0]; |
| 1725 | consumer_sockpoll[0].events = POLLIN | POLLPRI; |
| 1726 | consumer_sockpoll[1].fd = client_socket; |
| 1727 | consumer_sockpoll[1].events = POLLIN | POLLPRI; |
| 1728 | |
| 1729 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { |
| 1730 | goto end; |
| 1731 | } |
| 1732 | DBG("Connection on client_socket"); |
| 1733 | |
| 1734 | /* Blocking call, waiting for transmission */ |
| 1735 | sock = lttcomm_accept_unix_sock(client_socket); |
| 1736 | if (sock <= 0) { |
| 1737 | WARN("On accept"); |
| 1738 | goto end; |
| 1739 | } |
| 1740 | ret = fcntl(sock, F_SETFL, O_NONBLOCK); |
| 1741 | if (ret < 0) { |
| 1742 | perror("fcntl O_NONBLOCK"); |
| 1743 | goto end; |
| 1744 | } |
| 1745 | |
| 1746 | /* update the polling structure to poll on the established socket */ |
| 1747 | consumer_sockpoll[1].fd = sock; |
| 1748 | consumer_sockpoll[1].events = POLLIN | POLLPRI; |
| 1749 | |
| 1750 | while (1) { |
| 1751 | if (lttng_consumer_poll_socket(consumer_sockpoll) < 0) { |
| 1752 | goto end; |
| 1753 | } |
| 1754 | DBG("Incoming command on sock"); |
| 1755 | ret = lttng_consumer_recv_cmd(ctx, sock, consumer_sockpoll); |
| 1756 | if (ret == -ENOENT) { |
| 1757 | DBG("Received STOP command"); |
| 1758 | goto end; |
| 1759 | } |
| 1760 | if (ret < 0) { |
| 1761 | ERR("Communication interrupted on command socket"); |
| 1762 | goto end; |
| 1763 | } |
| 1764 | if (consumer_quit) { |
| 1765 | DBG("consumer_thread_receive_fds received quit from signal"); |
| 1766 | goto end; |
| 1767 | } |
| 1768 | DBG("received fds on sock"); |
| 1769 | } |
| 1770 | end: |
| 1771 | DBG("consumer_thread_receive_fds exiting"); |
| 1772 | |
| 1773 | /* |
| 1774 | * when all fds have hung up, the polling thread |
| 1775 | * can exit cleanly |
| 1776 | */ |
| 1777 | consumer_quit = 1; |
| 1778 | |
| 1779 | /* |
| 1780 | * 2s of grace period, if no polling events occur during |
| 1781 | * this period, the polling thread will exit even if there |
| 1782 | * are still open FDs (should not happen, but safety mechanism). |
| 1783 | */ |
| 1784 | consumer_poll_timeout = LTTNG_CONSUMER_POLL_TIMEOUT; |
| 1785 | |
| 1786 | /* |
| 1787 | * Wake-up the other end by writing a null byte in the pipe |
| 1788 | * (non-blocking). Important note: Because writing into the |
| 1789 | * pipe is non-blocking (and therefore we allow dropping wakeup |
| 1790 | * data, as long as there is wakeup data present in the pipe |
| 1791 | * buffer to wake up the other end), the other end should |
| 1792 | * perform the following sequence for waiting: |
| 1793 | * 1) empty the pipe (reads). |
| 1794 | * 2) perform update operation. |
| 1795 | * 3) wait on the pipe (poll). |
| 1796 | */ |
| 1797 | do { |
| 1798 | ret = write(ctx->consumer_poll_pipe[1], "", 1); |
| 1799 | } while (ret < 0 && errno == EINTR); |
| 1800 | rcu_unregister_thread(); |
| 1801 | return NULL; |
| 1802 | } |
| 1803 | |
| 1804 | ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream, |
| 1805 | struct lttng_consumer_local_data *ctx) |
| 1806 | { |
| 1807 | switch (consumer_data.type) { |
| 1808 | case LTTNG_CONSUMER_KERNEL: |
| 1809 | return lttng_kconsumer_read_subbuffer(stream, ctx); |
| 1810 | case LTTNG_CONSUMER32_UST: |
| 1811 | case LTTNG_CONSUMER64_UST: |
| 1812 | return lttng_ustconsumer_read_subbuffer(stream, ctx); |
| 1813 | default: |
| 1814 | ERR("Unknown consumer_data type"); |
| 1815 | assert(0); |
| 1816 | return -ENOSYS; |
| 1817 | } |
| 1818 | } |
| 1819 | |
| 1820 | int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream) |
| 1821 | { |
| 1822 | switch (consumer_data.type) { |
| 1823 | case LTTNG_CONSUMER_KERNEL: |
| 1824 | return lttng_kconsumer_on_recv_stream(stream); |
| 1825 | case LTTNG_CONSUMER32_UST: |
| 1826 | case LTTNG_CONSUMER64_UST: |
| 1827 | return lttng_ustconsumer_on_recv_stream(stream); |
| 1828 | default: |
| 1829 | ERR("Unknown consumer_data type"); |
| 1830 | assert(0); |
| 1831 | return -ENOSYS; |
| 1832 | } |
| 1833 | } |
| 1834 | |
| 1835 | /* |
| 1836 | * Allocate and set consumer data hash tables. |
| 1837 | */ |
| 1838 | void lttng_consumer_init(void) |
| 1839 | { |
| 1840 | consumer_data.stream_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); |
| 1841 | consumer_data.channel_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); |
| 1842 | consumer_data.relayd_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG); |
| 1843 | } |