1 /* 2 * QEMU live migration 3 * 4 * Copyright IBM, Corp. 2008 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 * Contributions after 2012-01-13 are licensed under the terms of the 13 * GNU GPL, version 2 or (at your option) any later version. 14 */ 15 16 #include "qemu/osdep.h" 17 #include "qemu/cutils.h" 18 #include "qemu/error-report.h" 19 #include "qemu/main-loop.h" 20 #include "migration/blocker.h" 21 #include "exec.h" 22 #include "fd.h" 23 #include "socket.h" 24 #include "rdma.h" 25 #include "ram.h" 26 #include "migration/migration.h" 27 #include "savevm.h" 28 #include "qemu-file-channel.h" 29 #include "qemu-file.h" 30 #include "migration/vmstate.h" 31 #include "sysemu/sysemu.h" 32 #include "block/block.h" 33 #include "qapi/qmp/qerror.h" 34 #include "qapi/util.h" 35 #include "qemu/sockets.h" 36 #include "qemu/rcu.h" 37 #include "block.h" 38 #include "postcopy-ram.h" 39 #include "qemu/thread.h" 40 #include "qmp-commands.h" 41 #include "trace.h" 42 #include "qapi-event.h" 43 #include "qom/cpu.h" 44 #include "exec/memory.h" 45 #include "exec/address-spaces.h" 46 #include "exec/target_page.h" 47 #include "io/channel-buffer.h" 48 #include "migration/colo.h" 49 50 #define MAX_THROTTLE (32 << 20) /* Migration transfer speed throttling */ 51 52 /* Amount of time to allocate to each "chunk" of bandwidth-throttled 53 * data. */ 54 #define BUFFER_DELAY 100 55 #define XFER_LIMIT_RATIO (1000 / BUFFER_DELAY) 56 57 /* Time in milliseconds we are allowed to stop the source, 58 * for sending the last part */ 59 #define DEFAULT_MIGRATE_SET_DOWNTIME 300 60 61 /* Maximum migrate downtime set to 2000 seconds */ 62 #define MAX_MIGRATE_DOWNTIME_SECONDS 2000 63 #define MAX_MIGRATE_DOWNTIME (MAX_MIGRATE_DOWNTIME_SECONDS * 1000) 64 65 /* Default compression thread count */ 66 #define DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT 8 67 /* Default decompression thread count, usually decompression is at 68 * least 4 times as fast as compression.*/ 69 #define DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT 2 70 /*0: means nocompress, 1: best speed, ... 9: best compress ratio */ 71 #define DEFAULT_MIGRATE_COMPRESS_LEVEL 1 72 /* Define default autoconverge cpu throttle migration parameters */ 73 #define DEFAULT_MIGRATE_CPU_THROTTLE_INITIAL 20 74 #define DEFAULT_MIGRATE_CPU_THROTTLE_INCREMENT 10 75 76 /* Migration XBZRLE default cache size */ 77 #define DEFAULT_MIGRATE_CACHE_SIZE (64 * 1024 * 1024) 78 79 /* The delay time (in ms) between two COLO checkpoints 80 * Note: Please change this default value to 10000 when we support hybrid mode. 81 */ 82 #define DEFAULT_MIGRATE_X_CHECKPOINT_DELAY 200 83 84 static NotifierList migration_state_notifiers = 85 NOTIFIER_LIST_INITIALIZER(migration_state_notifiers); 86 87 static bool deferred_incoming; 88 89 /* When we add fault tolerance, we could have several 90 migrations at once. For now we don't need to add 91 dynamic creation of migration */ 92 93 /* For outgoing */ 94 MigrationState *migrate_get_current(void) 95 { 96 static bool once; 97 static MigrationState current_migration = { 98 .state = MIGRATION_STATUS_NONE, 99 .xbzrle_cache_size = DEFAULT_MIGRATE_CACHE_SIZE, 100 .mbps = -1, 101 .parameters = { 102 .compress_level = DEFAULT_MIGRATE_COMPRESS_LEVEL, 103 .compress_threads = DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT, 104 .decompress_threads = DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT, 105 .cpu_throttle_initial = DEFAULT_MIGRATE_CPU_THROTTLE_INITIAL, 106 .cpu_throttle_increment = DEFAULT_MIGRATE_CPU_THROTTLE_INCREMENT, 107 .max_bandwidth = MAX_THROTTLE, 108 .downtime_limit = DEFAULT_MIGRATE_SET_DOWNTIME, 109 .x_checkpoint_delay = DEFAULT_MIGRATE_X_CHECKPOINT_DELAY, 110 }, 111 }; 112 113 if (!once) { 114 current_migration.parameters.tls_creds = g_strdup(""); 115 current_migration.parameters.tls_hostname = g_strdup(""); 116 once = true; 117 } 118 return ¤t_migration; 119 } 120 121 MigrationIncomingState *migration_incoming_get_current(void) 122 { 123 static bool once; 124 static MigrationIncomingState mis_current; 125 126 if (!once) { 127 mis_current.state = MIGRATION_STATUS_NONE; 128 memset(&mis_current, 0, sizeof(MigrationIncomingState)); 129 qemu_mutex_init(&mis_current.rp_mutex); 130 qemu_event_init(&mis_current.main_thread_load_event, false); 131 once = true; 132 } 133 return &mis_current; 134 } 135 136 void migration_incoming_state_destroy(void) 137 { 138 struct MigrationIncomingState *mis = migration_incoming_get_current(); 139 140 if (mis->to_src_file) { 141 /* Tell source that we are done */ 142 migrate_send_rp_shut(mis, qemu_file_get_error(mis->from_src_file) != 0); 143 qemu_fclose(mis->to_src_file); 144 mis->to_src_file = NULL; 145 } 146 147 if (mis->from_src_file) { 148 qemu_fclose(mis->from_src_file); 149 mis->from_src_file = NULL; 150 } 151 152 qemu_event_destroy(&mis->main_thread_load_event); 153 } 154 155 156 typedef struct { 157 bool optional; 158 uint32_t size; 159 uint8_t runstate[100]; 160 RunState state; 161 bool received; 162 } GlobalState; 163 164 static GlobalState global_state; 165 166 int global_state_store(void) 167 { 168 if (!runstate_store((char *)global_state.runstate, 169 sizeof(global_state.runstate))) { 170 error_report("runstate name too big: %s", global_state.runstate); 171 trace_migrate_state_too_big(); 172 return -EINVAL; 173 } 174 return 0; 175 } 176 177 void global_state_store_running(void) 178 { 179 const char *state = RunState_lookup[RUN_STATE_RUNNING]; 180 strncpy((char *)global_state.runstate, 181 state, sizeof(global_state.runstate)); 182 } 183 184 static bool global_state_received(void) 185 { 186 return global_state.received; 187 } 188 189 static RunState global_state_get_runstate(void) 190 { 191 return global_state.state; 192 } 193 194 void global_state_set_optional(void) 195 { 196 global_state.optional = true; 197 } 198 199 static bool global_state_needed(void *opaque) 200 { 201 GlobalState *s = opaque; 202 char *runstate = (char *)s->runstate; 203 204 /* If it is not optional, it is mandatory */ 205 206 if (s->optional == false) { 207 return true; 208 } 209 210 /* If state is running or paused, it is not needed */ 211 212 if (strcmp(runstate, "running") == 0 || 213 strcmp(runstate, "paused") == 0) { 214 return false; 215 } 216 217 /* for any other state it is needed */ 218 return true; 219 } 220 221 static int global_state_post_load(void *opaque, int version_id) 222 { 223 GlobalState *s = opaque; 224 Error *local_err = NULL; 225 int r; 226 char *runstate = (char *)s->runstate; 227 228 s->received = true; 229 trace_migrate_global_state_post_load(runstate); 230 231 r = qapi_enum_parse(RunState_lookup, runstate, RUN_STATE__MAX, 232 -1, &local_err); 233 234 if (r == -1) { 235 if (local_err) { 236 error_report_err(local_err); 237 } 238 return -EINVAL; 239 } 240 s->state = r; 241 242 return 0; 243 } 244 245 static void global_state_pre_save(void *opaque) 246 { 247 GlobalState *s = opaque; 248 249 trace_migrate_global_state_pre_save((char *)s->runstate); 250 s->size = strlen((char *)s->runstate) + 1; 251 } 252 253 static const VMStateDescription vmstate_globalstate = { 254 .name = "globalstate", 255 .version_id = 1, 256 .minimum_version_id = 1, 257 .post_load = global_state_post_load, 258 .pre_save = global_state_pre_save, 259 .needed = global_state_needed, 260 .fields = (VMStateField[]) { 261 VMSTATE_UINT32(size, GlobalState), 262 VMSTATE_BUFFER(runstate, GlobalState), 263 VMSTATE_END_OF_LIST() 264 }, 265 }; 266 267 void register_global_state(void) 268 { 269 /* We would use it independently that we receive it */ 270 strcpy((char *)&global_state.runstate, ""); 271 global_state.received = false; 272 vmstate_register(NULL, 0, &vmstate_globalstate, &global_state); 273 } 274 275 static void migrate_generate_event(int new_state) 276 { 277 if (migrate_use_events()) { 278 qapi_event_send_migration(new_state, &error_abort); 279 } 280 } 281 282 /* 283 * Called on -incoming with a defer: uri. 284 * The migration can be started later after any parameters have been 285 * changed. 286 */ 287 static void deferred_incoming_migration(Error **errp) 288 { 289 if (deferred_incoming) { 290 error_setg(errp, "Incoming migration already deferred"); 291 } 292 deferred_incoming = true; 293 } 294 295 /* Request a range of pages from the source VM at the given 296 * start address. 297 * rbname: Name of the RAMBlock to request the page in, if NULL it's the same 298 * as the last request (a name must have been given previously) 299 * Start: Address offset within the RB 300 * Len: Length in bytes required - must be a multiple of pagesize 301 */ 302 void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char *rbname, 303 ram_addr_t start, size_t len) 304 { 305 uint8_t bufc[12 + 1 + 255]; /* start (8), len (4), rbname up to 256 */ 306 size_t msglen = 12; /* start + len */ 307 308 *(uint64_t *)bufc = cpu_to_be64((uint64_t)start); 309 *(uint32_t *)(bufc + 8) = cpu_to_be32((uint32_t)len); 310 311 if (rbname) { 312 int rbname_len = strlen(rbname); 313 assert(rbname_len < 256); 314 315 bufc[msglen++] = rbname_len; 316 memcpy(bufc + msglen, rbname, rbname_len); 317 msglen += rbname_len; 318 migrate_send_rp_message(mis, MIG_RP_MSG_REQ_PAGES_ID, msglen, bufc); 319 } else { 320 migrate_send_rp_message(mis, MIG_RP_MSG_REQ_PAGES, msglen, bufc); 321 } 322 } 323 324 void qemu_start_incoming_migration(const char *uri, Error **errp) 325 { 326 const char *p; 327 328 qapi_event_send_migration(MIGRATION_STATUS_SETUP, &error_abort); 329 if (!strcmp(uri, "defer")) { 330 deferred_incoming_migration(errp); 331 } else if (strstart(uri, "tcp:", &p)) { 332 tcp_start_incoming_migration(p, errp); 333 #ifdef CONFIG_RDMA 334 } else if (strstart(uri, "rdma:", &p)) { 335 rdma_start_incoming_migration(p, errp); 336 #endif 337 } else if (strstart(uri, "exec:", &p)) { 338 exec_start_incoming_migration(p, errp); 339 } else if (strstart(uri, "unix:", &p)) { 340 unix_start_incoming_migration(p, errp); 341 } else if (strstart(uri, "fd:", &p)) { 342 fd_start_incoming_migration(p, errp); 343 } else { 344 error_setg(errp, "unknown migration protocol: %s", uri); 345 } 346 } 347 348 static void process_incoming_migration_bh(void *opaque) 349 { 350 Error *local_err = NULL; 351 MigrationIncomingState *mis = opaque; 352 353 /* Make sure all file formats flush their mutable metadata. 354 * If we get an error here, just don't restart the VM yet. */ 355 bdrv_invalidate_cache_all(&local_err); 356 if (local_err) { 357 error_report_err(local_err); 358 local_err = NULL; 359 autostart = false; 360 } 361 362 /* 363 * This must happen after all error conditions are dealt with and 364 * we're sure the VM is going to be running on this host. 365 */ 366 qemu_announce_self(); 367 368 /* If global state section was not received or we are in running 369 state, we need to obey autostart. Any other state is set with 370 runstate_set. */ 371 372 if (!global_state_received() || 373 global_state_get_runstate() == RUN_STATE_RUNNING) { 374 if (autostart) { 375 vm_start(); 376 } else { 377 runstate_set(RUN_STATE_PAUSED); 378 } 379 } else { 380 runstate_set(global_state_get_runstate()); 381 } 382 migrate_decompress_threads_join(); 383 /* 384 * This must happen after any state changes since as soon as an external 385 * observer sees this event they might start to prod at the VM assuming 386 * it's ready to use. 387 */ 388 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE, 389 MIGRATION_STATUS_COMPLETED); 390 qemu_bh_delete(mis->bh); 391 migration_incoming_state_destroy(); 392 } 393 394 static void process_incoming_migration_co(void *opaque) 395 { 396 QEMUFile *f = opaque; 397 MigrationIncomingState *mis = migration_incoming_get_current(); 398 PostcopyState ps; 399 int ret; 400 401 mis->from_src_file = f; 402 mis->largest_page_size = qemu_ram_pagesize_largest(); 403 postcopy_state_set(POSTCOPY_INCOMING_NONE); 404 migrate_set_state(&mis->state, MIGRATION_STATUS_NONE, 405 MIGRATION_STATUS_ACTIVE); 406 ret = qemu_loadvm_state(f); 407 408 ps = postcopy_state_get(); 409 trace_process_incoming_migration_co_end(ret, ps); 410 if (ps != POSTCOPY_INCOMING_NONE) { 411 if (ps == POSTCOPY_INCOMING_ADVISE) { 412 /* 413 * Where a migration had postcopy enabled (and thus went to advise) 414 * but managed to complete within the precopy period, we can use 415 * the normal exit. 416 */ 417 postcopy_ram_incoming_cleanup(mis); 418 } else if (ret >= 0) { 419 /* 420 * Postcopy was started, cleanup should happen at the end of the 421 * postcopy thread. 422 */ 423 trace_process_incoming_migration_co_postcopy_end_main(); 424 return; 425 } 426 /* Else if something went wrong then just fall out of the normal exit */ 427 } 428 429 /* we get COLO info, and know if we are in COLO mode */ 430 if (!ret && migration_incoming_enable_colo()) { 431 mis->migration_incoming_co = qemu_coroutine_self(); 432 qemu_thread_create(&mis->colo_incoming_thread, "COLO incoming", 433 colo_process_incoming_thread, mis, QEMU_THREAD_JOINABLE); 434 mis->have_colo_incoming_thread = true; 435 qemu_coroutine_yield(); 436 437 /* Wait checkpoint incoming thread exit before free resource */ 438 qemu_thread_join(&mis->colo_incoming_thread); 439 } 440 441 if (ret < 0) { 442 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE, 443 MIGRATION_STATUS_FAILED); 444 error_report("load of migration failed: %s", strerror(-ret)); 445 migrate_decompress_threads_join(); 446 exit(EXIT_FAILURE); 447 } 448 449 free_xbzrle_decoded_buf(); 450 451 mis->bh = qemu_bh_new(process_incoming_migration_bh, mis); 452 qemu_bh_schedule(mis->bh); 453 } 454 455 void migration_fd_process_incoming(QEMUFile *f) 456 { 457 Coroutine *co = qemu_coroutine_create(process_incoming_migration_co, f); 458 459 migrate_decompress_threads_create(); 460 qemu_file_set_blocking(f, false); 461 qemu_coroutine_enter(co); 462 } 463 464 /* 465 * Send a message on the return channel back to the source 466 * of the migration. 467 */ 468 void migrate_send_rp_message(MigrationIncomingState *mis, 469 enum mig_rp_message_type message_type, 470 uint16_t len, void *data) 471 { 472 trace_migrate_send_rp_message((int)message_type, len); 473 qemu_mutex_lock(&mis->rp_mutex); 474 qemu_put_be16(mis->to_src_file, (unsigned int)message_type); 475 qemu_put_be16(mis->to_src_file, len); 476 qemu_put_buffer(mis->to_src_file, data, len); 477 qemu_fflush(mis->to_src_file); 478 qemu_mutex_unlock(&mis->rp_mutex); 479 } 480 481 /* 482 * Send a 'SHUT' message on the return channel with the given value 483 * to indicate that we've finished with the RP. Non-0 value indicates 484 * error. 485 */ 486 void migrate_send_rp_shut(MigrationIncomingState *mis, 487 uint32_t value) 488 { 489 uint32_t buf; 490 491 buf = cpu_to_be32(value); 492 migrate_send_rp_message(mis, MIG_RP_MSG_SHUT, sizeof(buf), &buf); 493 } 494 495 /* 496 * Send a 'PONG' message on the return channel with the given value 497 * (normally in response to a 'PING') 498 */ 499 void migrate_send_rp_pong(MigrationIncomingState *mis, 500 uint32_t value) 501 { 502 uint32_t buf; 503 504 buf = cpu_to_be32(value); 505 migrate_send_rp_message(mis, MIG_RP_MSG_PONG, sizeof(buf), &buf); 506 } 507 508 MigrationCapabilityStatusList *qmp_query_migrate_capabilities(Error **errp) 509 { 510 MigrationCapabilityStatusList *head = NULL; 511 MigrationCapabilityStatusList *caps; 512 MigrationState *s = migrate_get_current(); 513 int i; 514 515 caps = NULL; /* silence compiler warning */ 516 for (i = 0; i < MIGRATION_CAPABILITY__MAX; i++) { 517 #ifndef CONFIG_LIVE_BLOCK_MIGRATION 518 if (i == MIGRATION_CAPABILITY_BLOCK) { 519 continue; 520 } 521 #endif 522 if (i == MIGRATION_CAPABILITY_X_COLO && !colo_supported()) { 523 continue; 524 } 525 if (head == NULL) { 526 head = g_malloc0(sizeof(*caps)); 527 caps = head; 528 } else { 529 caps->next = g_malloc0(sizeof(*caps)); 530 caps = caps->next; 531 } 532 caps->value = 533 g_malloc(sizeof(*caps->value)); 534 caps->value->capability = i; 535 caps->value->state = s->enabled_capabilities[i]; 536 } 537 538 return head; 539 } 540 541 MigrationParameters *qmp_query_migrate_parameters(Error **errp) 542 { 543 MigrationParameters *params; 544 MigrationState *s = migrate_get_current(); 545 546 params = g_malloc0(sizeof(*params)); 547 params->has_compress_level = true; 548 params->compress_level = s->parameters.compress_level; 549 params->has_compress_threads = true; 550 params->compress_threads = s->parameters.compress_threads; 551 params->has_decompress_threads = true; 552 params->decompress_threads = s->parameters.decompress_threads; 553 params->has_cpu_throttle_initial = true; 554 params->cpu_throttle_initial = s->parameters.cpu_throttle_initial; 555 params->has_cpu_throttle_increment = true; 556 params->cpu_throttle_increment = s->parameters.cpu_throttle_increment; 557 params->has_tls_creds = !!s->parameters.tls_creds; 558 params->tls_creds = g_strdup(s->parameters.tls_creds); 559 params->has_tls_hostname = !!s->parameters.tls_hostname; 560 params->tls_hostname = g_strdup(s->parameters.tls_hostname); 561 params->has_max_bandwidth = true; 562 params->max_bandwidth = s->parameters.max_bandwidth; 563 params->has_downtime_limit = true; 564 params->downtime_limit = s->parameters.downtime_limit; 565 params->has_x_checkpoint_delay = true; 566 params->x_checkpoint_delay = s->parameters.x_checkpoint_delay; 567 params->has_block_incremental = true; 568 params->block_incremental = s->parameters.block_incremental; 569 570 return params; 571 } 572 573 /* 574 * Return true if we're already in the middle of a migration 575 * (i.e. any of the active or setup states) 576 */ 577 static bool migration_is_setup_or_active(int state) 578 { 579 switch (state) { 580 case MIGRATION_STATUS_ACTIVE: 581 case MIGRATION_STATUS_POSTCOPY_ACTIVE: 582 case MIGRATION_STATUS_SETUP: 583 return true; 584 585 default: 586 return false; 587 588 } 589 } 590 591 static void get_xbzrle_cache_stats(MigrationInfo *info) 592 { 593 if (migrate_use_xbzrle()) { 594 info->has_xbzrle_cache = true; 595 info->xbzrle_cache = g_malloc0(sizeof(*info->xbzrle_cache)); 596 info->xbzrle_cache->cache_size = migrate_xbzrle_cache_size(); 597 info->xbzrle_cache->bytes = xbzrle_mig_bytes_transferred(); 598 info->xbzrle_cache->pages = xbzrle_mig_pages_transferred(); 599 info->xbzrle_cache->cache_miss = xbzrle_mig_pages_cache_miss(); 600 info->xbzrle_cache->cache_miss_rate = xbzrle_mig_cache_miss_rate(); 601 info->xbzrle_cache->overflow = xbzrle_mig_pages_overflow(); 602 } 603 } 604 605 static void populate_ram_info(MigrationInfo *info, MigrationState *s) 606 { 607 info->has_ram = true; 608 info->ram = g_malloc0(sizeof(*info->ram)); 609 info->ram->transferred = ram_bytes_transferred(); 610 info->ram->total = ram_bytes_total(); 611 info->ram->duplicate = dup_mig_pages_transferred(); 612 /* legacy value. It is not used anymore */ 613 info->ram->skipped = 0; 614 info->ram->normal = norm_mig_pages_transferred(); 615 info->ram->normal_bytes = norm_mig_pages_transferred() * 616 qemu_target_page_size(); 617 info->ram->mbps = s->mbps; 618 info->ram->dirty_sync_count = ram_dirty_sync_count(); 619 info->ram->postcopy_requests = ram_postcopy_requests(); 620 info->ram->page_size = qemu_target_page_size(); 621 622 if (s->state != MIGRATION_STATUS_COMPLETED) { 623 info->ram->remaining = ram_bytes_remaining(); 624 info->ram->dirty_pages_rate = ram_dirty_pages_rate(); 625 } 626 } 627 628 MigrationInfo *qmp_query_migrate(Error **errp) 629 { 630 MigrationInfo *info = g_malloc0(sizeof(*info)); 631 MigrationState *s = migrate_get_current(); 632 633 switch (s->state) { 634 case MIGRATION_STATUS_NONE: 635 /* no migration has happened ever */ 636 break; 637 case MIGRATION_STATUS_SETUP: 638 info->has_status = true; 639 info->has_total_time = false; 640 break; 641 case MIGRATION_STATUS_ACTIVE: 642 case MIGRATION_STATUS_CANCELLING: 643 info->has_status = true; 644 info->has_total_time = true; 645 info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) 646 - s->total_time; 647 info->has_expected_downtime = true; 648 info->expected_downtime = s->expected_downtime; 649 info->has_setup_time = true; 650 info->setup_time = s->setup_time; 651 652 populate_ram_info(info, s); 653 654 if (blk_mig_active()) { 655 info->has_disk = true; 656 info->disk = g_malloc0(sizeof(*info->disk)); 657 info->disk->transferred = blk_mig_bytes_transferred(); 658 info->disk->remaining = blk_mig_bytes_remaining(); 659 info->disk->total = blk_mig_bytes_total(); 660 } 661 662 if (cpu_throttle_active()) { 663 info->has_cpu_throttle_percentage = true; 664 info->cpu_throttle_percentage = cpu_throttle_get_percentage(); 665 } 666 667 get_xbzrle_cache_stats(info); 668 break; 669 case MIGRATION_STATUS_POSTCOPY_ACTIVE: 670 /* Mostly the same as active; TODO add some postcopy stats */ 671 info->has_status = true; 672 info->has_total_time = true; 673 info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) 674 - s->total_time; 675 info->has_expected_downtime = true; 676 info->expected_downtime = s->expected_downtime; 677 info->has_setup_time = true; 678 info->setup_time = s->setup_time; 679 680 populate_ram_info(info, s); 681 682 if (blk_mig_active()) { 683 info->has_disk = true; 684 info->disk = g_malloc0(sizeof(*info->disk)); 685 info->disk->transferred = blk_mig_bytes_transferred(); 686 info->disk->remaining = blk_mig_bytes_remaining(); 687 info->disk->total = blk_mig_bytes_total(); 688 } 689 690 get_xbzrle_cache_stats(info); 691 break; 692 case MIGRATION_STATUS_COLO: 693 info->has_status = true; 694 /* TODO: display COLO specific information (checkpoint info etc.) */ 695 break; 696 case MIGRATION_STATUS_COMPLETED: 697 get_xbzrle_cache_stats(info); 698 699 info->has_status = true; 700 info->has_total_time = true; 701 info->total_time = s->total_time; 702 info->has_downtime = true; 703 info->downtime = s->downtime; 704 info->has_setup_time = true; 705 info->setup_time = s->setup_time; 706 707 populate_ram_info(info, s); 708 break; 709 case MIGRATION_STATUS_FAILED: 710 info->has_status = true; 711 if (s->error) { 712 info->has_error_desc = true; 713 info->error_desc = g_strdup(error_get_pretty(s->error)); 714 } 715 break; 716 case MIGRATION_STATUS_CANCELLED: 717 info->has_status = true; 718 break; 719 } 720 info->status = s->state; 721 722 return info; 723 } 724 725 void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params, 726 Error **errp) 727 { 728 MigrationState *s = migrate_get_current(); 729 MigrationCapabilityStatusList *cap; 730 bool old_postcopy_cap = migrate_postcopy_ram(); 731 732 if (migration_is_setup_or_active(s->state)) { 733 error_setg(errp, QERR_MIGRATION_ACTIVE); 734 return; 735 } 736 737 for (cap = params; cap; cap = cap->next) { 738 #ifndef CONFIG_LIVE_BLOCK_MIGRATION 739 if (cap->value->capability == MIGRATION_CAPABILITY_BLOCK 740 && cap->value->state) { 741 error_setg(errp, "QEMU compiled without old-style (blk/-b, inc/-i) " 742 "block migration"); 743 error_append_hint(errp, "Use drive_mirror+NBD instead.\n"); 744 continue; 745 } 746 #endif 747 if (cap->value->capability == MIGRATION_CAPABILITY_X_COLO) { 748 if (!colo_supported()) { 749 error_setg(errp, "COLO is not currently supported, please" 750 " configure with --enable-colo option in order to" 751 " support COLO feature"); 752 continue; 753 } 754 } 755 s->enabled_capabilities[cap->value->capability] = cap->value->state; 756 } 757 758 if (migrate_postcopy_ram()) { 759 if (migrate_use_compression()) { 760 /* The decompression threads asynchronously write into RAM 761 * rather than use the atomic copies needed to avoid 762 * userfaulting. It should be possible to fix the decompression 763 * threads for compatibility in future. 764 */ 765 error_report("Postcopy is not currently compatible with " 766 "compression"); 767 s->enabled_capabilities[MIGRATION_CAPABILITY_POSTCOPY_RAM] = 768 false; 769 } 770 /* This check is reasonably expensive, so only when it's being 771 * set the first time, also it's only the destination that needs 772 * special support. 773 */ 774 if (!old_postcopy_cap && runstate_check(RUN_STATE_INMIGRATE) && 775 !postcopy_ram_supported_by_host()) { 776 /* postcopy_ram_supported_by_host will have emitted a more 777 * detailed message 778 */ 779 error_report("Postcopy is not supported"); 780 s->enabled_capabilities[MIGRATION_CAPABILITY_POSTCOPY_RAM] = 781 false; 782 } 783 } 784 } 785 786 void qmp_migrate_set_parameters(MigrationParameters *params, Error **errp) 787 { 788 MigrationState *s = migrate_get_current(); 789 790 if (params->has_compress_level && 791 (params->compress_level < 0 || params->compress_level > 9)) { 792 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "compress_level", 793 "is invalid, it should be in the range of 0 to 9"); 794 return; 795 } 796 if (params->has_compress_threads && 797 (params->compress_threads < 1 || params->compress_threads > 255)) { 798 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, 799 "compress_threads", 800 "is invalid, it should be in the range of 1 to 255"); 801 return; 802 } 803 if (params->has_decompress_threads && 804 (params->decompress_threads < 1 || params->decompress_threads > 255)) { 805 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, 806 "decompress_threads", 807 "is invalid, it should be in the range of 1 to 255"); 808 return; 809 } 810 if (params->has_cpu_throttle_initial && 811 (params->cpu_throttle_initial < 1 || 812 params->cpu_throttle_initial > 99)) { 813 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, 814 "cpu_throttle_initial", 815 "an integer in the range of 1 to 99"); 816 return; 817 } 818 if (params->has_cpu_throttle_increment && 819 (params->cpu_throttle_increment < 1 || 820 params->cpu_throttle_increment > 99)) { 821 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, 822 "cpu_throttle_increment", 823 "an integer in the range of 1 to 99"); 824 return; 825 } 826 if (params->has_max_bandwidth && 827 (params->max_bandwidth < 0 || params->max_bandwidth > SIZE_MAX)) { 828 error_setg(errp, "Parameter 'max_bandwidth' expects an integer in the" 829 " range of 0 to %zu bytes/second", SIZE_MAX); 830 return; 831 } 832 if (params->has_downtime_limit && 833 (params->downtime_limit < 0 || 834 params->downtime_limit > MAX_MIGRATE_DOWNTIME)) { 835 error_setg(errp, "Parameter 'downtime_limit' expects an integer in " 836 "the range of 0 to %d milliseconds", 837 MAX_MIGRATE_DOWNTIME); 838 return; 839 } 840 if (params->has_x_checkpoint_delay && (params->x_checkpoint_delay < 0)) { 841 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, 842 "x_checkpoint_delay", 843 "is invalid, it should be positive"); 844 } 845 846 if (params->has_compress_level) { 847 s->parameters.compress_level = params->compress_level; 848 } 849 if (params->has_compress_threads) { 850 s->parameters.compress_threads = params->compress_threads; 851 } 852 if (params->has_decompress_threads) { 853 s->parameters.decompress_threads = params->decompress_threads; 854 } 855 if (params->has_cpu_throttle_initial) { 856 s->parameters.cpu_throttle_initial = params->cpu_throttle_initial; 857 } 858 if (params->has_cpu_throttle_increment) { 859 s->parameters.cpu_throttle_increment = params->cpu_throttle_increment; 860 } 861 if (params->has_tls_creds) { 862 g_free(s->parameters.tls_creds); 863 s->parameters.tls_creds = g_strdup(params->tls_creds); 864 } 865 if (params->has_tls_hostname) { 866 g_free(s->parameters.tls_hostname); 867 s->parameters.tls_hostname = g_strdup(params->tls_hostname); 868 } 869 if (params->has_max_bandwidth) { 870 s->parameters.max_bandwidth = params->max_bandwidth; 871 if (s->to_dst_file) { 872 qemu_file_set_rate_limit(s->to_dst_file, 873 s->parameters.max_bandwidth / XFER_LIMIT_RATIO); 874 } 875 } 876 if (params->has_downtime_limit) { 877 s->parameters.downtime_limit = params->downtime_limit; 878 } 879 880 if (params->has_x_checkpoint_delay) { 881 s->parameters.x_checkpoint_delay = params->x_checkpoint_delay; 882 if (migration_in_colo_state()) { 883 colo_checkpoint_notify(s); 884 } 885 } 886 if (params->has_block_incremental) { 887 s->parameters.block_incremental = params->block_incremental; 888 } 889 } 890 891 892 void qmp_migrate_start_postcopy(Error **errp) 893 { 894 MigrationState *s = migrate_get_current(); 895 896 if (!migrate_postcopy_ram()) { 897 error_setg(errp, "Enable postcopy with migrate_set_capability before" 898 " the start of migration"); 899 return; 900 } 901 902 if (s->state == MIGRATION_STATUS_NONE) { 903 error_setg(errp, "Postcopy must be started after migration has been" 904 " started"); 905 return; 906 } 907 /* 908 * we don't error if migration has finished since that would be racy 909 * with issuing this command. 910 */ 911 atomic_set(&s->start_postcopy, true); 912 } 913 914 /* shared migration helpers */ 915 916 void migrate_set_state(int *state, int old_state, int new_state) 917 { 918 if (atomic_cmpxchg(state, old_state, new_state) == old_state) { 919 trace_migrate_set_state(new_state); 920 migrate_generate_event(new_state); 921 } 922 } 923 924 void migrate_set_block_enabled(bool value, Error **errp) 925 { 926 MigrationCapabilityStatusList *cap; 927 928 cap = g_new0(MigrationCapabilityStatusList, 1); 929 cap->value = g_new0(MigrationCapabilityStatus, 1); 930 cap->value->capability = MIGRATION_CAPABILITY_BLOCK; 931 cap->value->state = value; 932 qmp_migrate_set_capabilities(cap, errp); 933 qapi_free_MigrationCapabilityStatusList(cap); 934 } 935 936 static void migrate_set_block_incremental(MigrationState *s, bool value) 937 { 938 s->parameters.block_incremental = value; 939 } 940 941 static void block_cleanup_parameters(MigrationState *s) 942 { 943 if (s->must_remove_block_options) { 944 /* setting to false can never fail */ 945 migrate_set_block_enabled(false, &error_abort); 946 migrate_set_block_incremental(s, false); 947 s->must_remove_block_options = false; 948 } 949 } 950 951 static void migrate_fd_cleanup(void *opaque) 952 { 953 MigrationState *s = opaque; 954 955 qemu_bh_delete(s->cleanup_bh); 956 s->cleanup_bh = NULL; 957 958 migration_page_queue_free(); 959 960 if (s->to_dst_file) { 961 trace_migrate_fd_cleanup(); 962 qemu_mutex_unlock_iothread(); 963 if (s->migration_thread_running) { 964 qemu_thread_join(&s->thread); 965 s->migration_thread_running = false; 966 } 967 qemu_mutex_lock_iothread(); 968 969 migrate_compress_threads_join(); 970 qemu_fclose(s->to_dst_file); 971 s->to_dst_file = NULL; 972 } 973 974 assert((s->state != MIGRATION_STATUS_ACTIVE) && 975 (s->state != MIGRATION_STATUS_POSTCOPY_ACTIVE)); 976 977 if (s->state == MIGRATION_STATUS_CANCELLING) { 978 migrate_set_state(&s->state, MIGRATION_STATUS_CANCELLING, 979 MIGRATION_STATUS_CANCELLED); 980 } 981 982 notifier_list_notify(&migration_state_notifiers, s); 983 block_cleanup_parameters(s); 984 } 985 986 void migrate_fd_error(MigrationState *s, const Error *error) 987 { 988 trace_migrate_fd_error(error_get_pretty(error)); 989 assert(s->to_dst_file == NULL); 990 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP, 991 MIGRATION_STATUS_FAILED); 992 if (!s->error) { 993 s->error = error_copy(error); 994 } 995 notifier_list_notify(&migration_state_notifiers, s); 996 block_cleanup_parameters(s); 997 } 998 999 static void migrate_fd_cancel(MigrationState *s) 1000 { 1001 int old_state ; 1002 QEMUFile *f = migrate_get_current()->to_dst_file; 1003 trace_migrate_fd_cancel(); 1004 1005 if (s->rp_state.from_dst_file) { 1006 /* shutdown the rp socket, so causing the rp thread to shutdown */ 1007 qemu_file_shutdown(s->rp_state.from_dst_file); 1008 } 1009 1010 do { 1011 old_state = s->state; 1012 if (!migration_is_setup_or_active(old_state)) { 1013 break; 1014 } 1015 migrate_set_state(&s->state, old_state, MIGRATION_STATUS_CANCELLING); 1016 } while (s->state != MIGRATION_STATUS_CANCELLING); 1017 1018 /* 1019 * If we're unlucky the migration code might be stuck somewhere in a 1020 * send/write while the network has failed and is waiting to timeout; 1021 * if we've got shutdown(2) available then we can force it to quit. 1022 * The outgoing qemu file gets closed in migrate_fd_cleanup that is 1023 * called in a bh, so there is no race against this cancel. 1024 */ 1025 if (s->state == MIGRATION_STATUS_CANCELLING && f) { 1026 qemu_file_shutdown(f); 1027 } 1028 if (s->state == MIGRATION_STATUS_CANCELLING && s->block_inactive) { 1029 Error *local_err = NULL; 1030 1031 bdrv_invalidate_cache_all(&local_err); 1032 if (local_err) { 1033 error_report_err(local_err); 1034 } else { 1035 s->block_inactive = false; 1036 } 1037 } 1038 block_cleanup_parameters(s); 1039 } 1040 1041 void add_migration_state_change_notifier(Notifier *notify) 1042 { 1043 notifier_list_add(&migration_state_notifiers, notify); 1044 } 1045 1046 void remove_migration_state_change_notifier(Notifier *notify) 1047 { 1048 notifier_remove(notify); 1049 } 1050 1051 bool migration_in_setup(MigrationState *s) 1052 { 1053 return s->state == MIGRATION_STATUS_SETUP; 1054 } 1055 1056 bool migration_has_finished(MigrationState *s) 1057 { 1058 return s->state == MIGRATION_STATUS_COMPLETED; 1059 } 1060 1061 bool migration_has_failed(MigrationState *s) 1062 { 1063 return (s->state == MIGRATION_STATUS_CANCELLED || 1064 s->state == MIGRATION_STATUS_FAILED); 1065 } 1066 1067 bool migration_in_postcopy(void) 1068 { 1069 MigrationState *s = migrate_get_current(); 1070 1071 return (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE); 1072 } 1073 1074 bool migration_in_postcopy_after_devices(MigrationState *s) 1075 { 1076 return migration_in_postcopy() && s->postcopy_after_devices; 1077 } 1078 1079 bool migration_is_idle(void) 1080 { 1081 MigrationState *s = migrate_get_current(); 1082 1083 switch (s->state) { 1084 case MIGRATION_STATUS_NONE: 1085 case MIGRATION_STATUS_CANCELLED: 1086 case MIGRATION_STATUS_COMPLETED: 1087 case MIGRATION_STATUS_FAILED: 1088 return true; 1089 case MIGRATION_STATUS_SETUP: 1090 case MIGRATION_STATUS_CANCELLING: 1091 case MIGRATION_STATUS_ACTIVE: 1092 case MIGRATION_STATUS_POSTCOPY_ACTIVE: 1093 case MIGRATION_STATUS_COLO: 1094 return false; 1095 case MIGRATION_STATUS__MAX: 1096 g_assert_not_reached(); 1097 } 1098 1099 return false; 1100 } 1101 1102 MigrationState *migrate_init(void) 1103 { 1104 MigrationState *s = migrate_get_current(); 1105 1106 /* 1107 * Reinitialise all migration state, except 1108 * parameters/capabilities that the user set, and 1109 * locks. 1110 */ 1111 s->bytes_xfer = 0; 1112 s->xfer_limit = 0; 1113 s->cleanup_bh = 0; 1114 s->to_dst_file = NULL; 1115 s->state = MIGRATION_STATUS_NONE; 1116 s->rp_state.from_dst_file = NULL; 1117 s->rp_state.error = false; 1118 s->mbps = 0.0; 1119 s->downtime = 0; 1120 s->expected_downtime = 0; 1121 s->setup_time = 0; 1122 s->start_postcopy = false; 1123 s->postcopy_after_devices = false; 1124 s->migration_thread_running = false; 1125 error_free(s->error); 1126 s->error = NULL; 1127 1128 migrate_set_state(&s->state, MIGRATION_STATUS_NONE, MIGRATION_STATUS_SETUP); 1129 1130 s->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 1131 return s; 1132 } 1133 1134 static GSList *migration_blockers; 1135 1136 int migrate_add_blocker(Error *reason, Error **errp) 1137 { 1138 if (only_migratable) { 1139 error_propagate(errp, error_copy(reason)); 1140 error_prepend(errp, "disallowing migration blocker " 1141 "(--only_migratable) for: "); 1142 return -EACCES; 1143 } 1144 1145 if (migration_is_idle()) { 1146 migration_blockers = g_slist_prepend(migration_blockers, reason); 1147 return 0; 1148 } 1149 1150 error_propagate(errp, error_copy(reason)); 1151 error_prepend(errp, "disallowing migration blocker (migration in " 1152 "progress) for: "); 1153 return -EBUSY; 1154 } 1155 1156 void migrate_del_blocker(Error *reason) 1157 { 1158 migration_blockers = g_slist_remove(migration_blockers, reason); 1159 } 1160 1161 void qmp_migrate_incoming(const char *uri, Error **errp) 1162 { 1163 Error *local_err = NULL; 1164 static bool once = true; 1165 1166 if (!deferred_incoming) { 1167 error_setg(errp, "For use with '-incoming defer'"); 1168 return; 1169 } 1170 if (!once) { 1171 error_setg(errp, "The incoming migration has already been started"); 1172 } 1173 1174 qemu_start_incoming_migration(uri, &local_err); 1175 1176 if (local_err) { 1177 error_propagate(errp, local_err); 1178 return; 1179 } 1180 1181 once = false; 1182 } 1183 1184 bool migration_is_blocked(Error **errp) 1185 { 1186 if (qemu_savevm_state_blocked(errp)) { 1187 return true; 1188 } 1189 1190 if (migration_blockers) { 1191 *errp = error_copy(migration_blockers->data); 1192 return true; 1193 } 1194 1195 return false; 1196 } 1197 1198 void qmp_migrate(const char *uri, bool has_blk, bool blk, 1199 bool has_inc, bool inc, bool has_detach, bool detach, 1200 Error **errp) 1201 { 1202 Error *local_err = NULL; 1203 MigrationState *s = migrate_get_current(); 1204 const char *p; 1205 1206 if (migration_is_setup_or_active(s->state) || 1207 s->state == MIGRATION_STATUS_CANCELLING || 1208 s->state == MIGRATION_STATUS_COLO) { 1209 error_setg(errp, QERR_MIGRATION_ACTIVE); 1210 return; 1211 } 1212 if (runstate_check(RUN_STATE_INMIGRATE)) { 1213 error_setg(errp, "Guest is waiting for an incoming migration"); 1214 return; 1215 } 1216 1217 if (migration_is_blocked(errp)) { 1218 return; 1219 } 1220 1221 if ((has_blk && blk) || (has_inc && inc)) { 1222 if (migrate_use_block() || migrate_use_block_incremental()) { 1223 error_setg(errp, "Command options are incompatible with " 1224 "current migration capabilities"); 1225 return; 1226 } 1227 migrate_set_block_enabled(true, &local_err); 1228 if (local_err) { 1229 error_propagate(errp, local_err); 1230 return; 1231 } 1232 s->must_remove_block_options = true; 1233 } 1234 1235 if (has_inc && inc) { 1236 migrate_set_block_incremental(s, true); 1237 } 1238 1239 s = migrate_init(); 1240 1241 if (strstart(uri, "tcp:", &p)) { 1242 tcp_start_outgoing_migration(s, p, &local_err); 1243 #ifdef CONFIG_RDMA 1244 } else if (strstart(uri, "rdma:", &p)) { 1245 rdma_start_outgoing_migration(s, p, &local_err); 1246 #endif 1247 } else if (strstart(uri, "exec:", &p)) { 1248 exec_start_outgoing_migration(s, p, &local_err); 1249 } else if (strstart(uri, "unix:", &p)) { 1250 unix_start_outgoing_migration(s, p, &local_err); 1251 } else if (strstart(uri, "fd:", &p)) { 1252 fd_start_outgoing_migration(s, p, &local_err); 1253 } else { 1254 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "uri", 1255 "a valid migration protocol"); 1256 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP, 1257 MIGRATION_STATUS_FAILED); 1258 return; 1259 } 1260 1261 if (local_err) { 1262 migrate_fd_error(s, local_err); 1263 error_propagate(errp, local_err); 1264 return; 1265 } 1266 } 1267 1268 void qmp_migrate_cancel(Error **errp) 1269 { 1270 migrate_fd_cancel(migrate_get_current()); 1271 } 1272 1273 void qmp_migrate_set_cache_size(int64_t value, Error **errp) 1274 { 1275 MigrationState *s = migrate_get_current(); 1276 int64_t new_size; 1277 1278 /* Check for truncation */ 1279 if (value != (size_t)value) { 1280 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cache size", 1281 "exceeding address space"); 1282 return; 1283 } 1284 1285 /* Cache should not be larger than guest ram size */ 1286 if (value > ram_bytes_total()) { 1287 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cache size", 1288 "exceeds guest ram size "); 1289 return; 1290 } 1291 1292 new_size = xbzrle_cache_resize(value); 1293 if (new_size < 0) { 1294 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cache size", 1295 "is smaller than page size"); 1296 return; 1297 } 1298 1299 s->xbzrle_cache_size = new_size; 1300 } 1301 1302 int64_t qmp_query_migrate_cache_size(Error **errp) 1303 { 1304 return migrate_xbzrle_cache_size(); 1305 } 1306 1307 void qmp_migrate_set_speed(int64_t value, Error **errp) 1308 { 1309 MigrationParameters p = { 1310 .has_max_bandwidth = true, 1311 .max_bandwidth = value, 1312 }; 1313 1314 qmp_migrate_set_parameters(&p, errp); 1315 } 1316 1317 void qmp_migrate_set_downtime(double value, Error **errp) 1318 { 1319 if (value < 0 || value > MAX_MIGRATE_DOWNTIME_SECONDS) { 1320 error_setg(errp, "Parameter 'downtime_limit' expects an integer in " 1321 "the range of 0 to %d seconds", 1322 MAX_MIGRATE_DOWNTIME_SECONDS); 1323 return; 1324 } 1325 1326 value *= 1000; /* Convert to milliseconds */ 1327 value = MAX(0, MIN(INT64_MAX, value)); 1328 1329 MigrationParameters p = { 1330 .has_downtime_limit = true, 1331 .downtime_limit = value, 1332 }; 1333 1334 qmp_migrate_set_parameters(&p, errp); 1335 } 1336 1337 bool migrate_release_ram(void) 1338 { 1339 MigrationState *s; 1340 1341 s = migrate_get_current(); 1342 1343 return s->enabled_capabilities[MIGRATION_CAPABILITY_RELEASE_RAM]; 1344 } 1345 1346 bool migrate_postcopy_ram(void) 1347 { 1348 MigrationState *s; 1349 1350 s = migrate_get_current(); 1351 1352 return s->enabled_capabilities[MIGRATION_CAPABILITY_POSTCOPY_RAM]; 1353 } 1354 1355 bool migrate_auto_converge(void) 1356 { 1357 MigrationState *s; 1358 1359 s = migrate_get_current(); 1360 1361 return s->enabled_capabilities[MIGRATION_CAPABILITY_AUTO_CONVERGE]; 1362 } 1363 1364 bool migrate_zero_blocks(void) 1365 { 1366 MigrationState *s; 1367 1368 s = migrate_get_current(); 1369 1370 return s->enabled_capabilities[MIGRATION_CAPABILITY_ZERO_BLOCKS]; 1371 } 1372 1373 bool migrate_use_compression(void) 1374 { 1375 MigrationState *s; 1376 1377 s = migrate_get_current(); 1378 1379 return s->enabled_capabilities[MIGRATION_CAPABILITY_COMPRESS]; 1380 } 1381 1382 int migrate_compress_level(void) 1383 { 1384 MigrationState *s; 1385 1386 s = migrate_get_current(); 1387 1388 return s->parameters.compress_level; 1389 } 1390 1391 int migrate_compress_threads(void) 1392 { 1393 MigrationState *s; 1394 1395 s = migrate_get_current(); 1396 1397 return s->parameters.compress_threads; 1398 } 1399 1400 int migrate_decompress_threads(void) 1401 { 1402 MigrationState *s; 1403 1404 s = migrate_get_current(); 1405 1406 return s->parameters.decompress_threads; 1407 } 1408 1409 bool migrate_use_events(void) 1410 { 1411 MigrationState *s; 1412 1413 s = migrate_get_current(); 1414 1415 return s->enabled_capabilities[MIGRATION_CAPABILITY_EVENTS]; 1416 } 1417 1418 int migrate_use_xbzrle(void) 1419 { 1420 MigrationState *s; 1421 1422 s = migrate_get_current(); 1423 1424 return s->enabled_capabilities[MIGRATION_CAPABILITY_XBZRLE]; 1425 } 1426 1427 int64_t migrate_xbzrle_cache_size(void) 1428 { 1429 MigrationState *s; 1430 1431 s = migrate_get_current(); 1432 1433 return s->xbzrle_cache_size; 1434 } 1435 1436 bool migrate_use_block(void) 1437 { 1438 MigrationState *s; 1439 1440 s = migrate_get_current(); 1441 1442 return s->enabled_capabilities[MIGRATION_CAPABILITY_BLOCK]; 1443 } 1444 1445 bool migrate_use_block_incremental(void) 1446 { 1447 MigrationState *s; 1448 1449 s = migrate_get_current(); 1450 1451 return s->parameters.block_incremental; 1452 } 1453 1454 /* migration thread support */ 1455 /* 1456 * Something bad happened to the RP stream, mark an error 1457 * The caller shall print or trace something to indicate why 1458 */ 1459 static void mark_source_rp_bad(MigrationState *s) 1460 { 1461 s->rp_state.error = true; 1462 } 1463 1464 static struct rp_cmd_args { 1465 ssize_t len; /* -1 = variable */ 1466 const char *name; 1467 } rp_cmd_args[] = { 1468 [MIG_RP_MSG_INVALID] = { .len = -1, .name = "INVALID" }, 1469 [MIG_RP_MSG_SHUT] = { .len = 4, .name = "SHUT" }, 1470 [MIG_RP_MSG_PONG] = { .len = 4, .name = "PONG" }, 1471 [MIG_RP_MSG_REQ_PAGES] = { .len = 12, .name = "REQ_PAGES" }, 1472 [MIG_RP_MSG_REQ_PAGES_ID] = { .len = -1, .name = "REQ_PAGES_ID" }, 1473 [MIG_RP_MSG_MAX] = { .len = -1, .name = "MAX" }, 1474 }; 1475 1476 /* 1477 * Process a request for pages received on the return path, 1478 * We're allowed to send more than requested (e.g. to round to our page size) 1479 * and we don't need to send pages that have already been sent. 1480 */ 1481 static void migrate_handle_rp_req_pages(MigrationState *ms, const char* rbname, 1482 ram_addr_t start, size_t len) 1483 { 1484 long our_host_ps = getpagesize(); 1485 1486 trace_migrate_handle_rp_req_pages(rbname, start, len); 1487 1488 /* 1489 * Since we currently insist on matching page sizes, just sanity check 1490 * we're being asked for whole host pages. 1491 */ 1492 if (start & (our_host_ps-1) || 1493 (len & (our_host_ps-1))) { 1494 error_report("%s: Misaligned page request, start: " RAM_ADDR_FMT 1495 " len: %zd", __func__, start, len); 1496 mark_source_rp_bad(ms); 1497 return; 1498 } 1499 1500 if (ram_save_queue_pages(rbname, start, len)) { 1501 mark_source_rp_bad(ms); 1502 } 1503 } 1504 1505 /* 1506 * Handles messages sent on the return path towards the source VM 1507 * 1508 */ 1509 static void *source_return_path_thread(void *opaque) 1510 { 1511 MigrationState *ms = opaque; 1512 QEMUFile *rp = ms->rp_state.from_dst_file; 1513 uint16_t header_len, header_type; 1514 uint8_t buf[512]; 1515 uint32_t tmp32, sibling_error; 1516 ram_addr_t start = 0; /* =0 to silence warning */ 1517 size_t len = 0, expected_len; 1518 int res; 1519 1520 trace_source_return_path_thread_entry(); 1521 while (!ms->rp_state.error && !qemu_file_get_error(rp) && 1522 migration_is_setup_or_active(ms->state)) { 1523 trace_source_return_path_thread_loop_top(); 1524 header_type = qemu_get_be16(rp); 1525 header_len = qemu_get_be16(rp); 1526 1527 if (header_type >= MIG_RP_MSG_MAX || 1528 header_type == MIG_RP_MSG_INVALID) { 1529 error_report("RP: Received invalid message 0x%04x length 0x%04x", 1530 header_type, header_len); 1531 mark_source_rp_bad(ms); 1532 goto out; 1533 } 1534 1535 if ((rp_cmd_args[header_type].len != -1 && 1536 header_len != rp_cmd_args[header_type].len) || 1537 header_len > sizeof(buf)) { 1538 error_report("RP: Received '%s' message (0x%04x) with" 1539 "incorrect length %d expecting %zu", 1540 rp_cmd_args[header_type].name, header_type, header_len, 1541 (size_t)rp_cmd_args[header_type].len); 1542 mark_source_rp_bad(ms); 1543 goto out; 1544 } 1545 1546 /* We know we've got a valid header by this point */ 1547 res = qemu_get_buffer(rp, buf, header_len); 1548 if (res != header_len) { 1549 error_report("RP: Failed reading data for message 0x%04x" 1550 " read %d expected %d", 1551 header_type, res, header_len); 1552 mark_source_rp_bad(ms); 1553 goto out; 1554 } 1555 1556 /* OK, we have the message and the data */ 1557 switch (header_type) { 1558 case MIG_RP_MSG_SHUT: 1559 sibling_error = ldl_be_p(buf); 1560 trace_source_return_path_thread_shut(sibling_error); 1561 if (sibling_error) { 1562 error_report("RP: Sibling indicated error %d", sibling_error); 1563 mark_source_rp_bad(ms); 1564 } 1565 /* 1566 * We'll let the main thread deal with closing the RP 1567 * we could do a shutdown(2) on it, but we're the only user 1568 * anyway, so there's nothing gained. 1569 */ 1570 goto out; 1571 1572 case MIG_RP_MSG_PONG: 1573 tmp32 = ldl_be_p(buf); 1574 trace_source_return_path_thread_pong(tmp32); 1575 break; 1576 1577 case MIG_RP_MSG_REQ_PAGES: 1578 start = ldq_be_p(buf); 1579 len = ldl_be_p(buf + 8); 1580 migrate_handle_rp_req_pages(ms, NULL, start, len); 1581 break; 1582 1583 case MIG_RP_MSG_REQ_PAGES_ID: 1584 expected_len = 12 + 1; /* header + termination */ 1585 1586 if (header_len >= expected_len) { 1587 start = ldq_be_p(buf); 1588 len = ldl_be_p(buf + 8); 1589 /* Now we expect an idstr */ 1590 tmp32 = buf[12]; /* Length of the following idstr */ 1591 buf[13 + tmp32] = '\0'; 1592 expected_len += tmp32; 1593 } 1594 if (header_len != expected_len) { 1595 error_report("RP: Req_Page_id with length %d expecting %zd", 1596 header_len, expected_len); 1597 mark_source_rp_bad(ms); 1598 goto out; 1599 } 1600 migrate_handle_rp_req_pages(ms, (char *)&buf[13], start, len); 1601 break; 1602 1603 default: 1604 break; 1605 } 1606 } 1607 if (qemu_file_get_error(rp)) { 1608 trace_source_return_path_thread_bad_end(); 1609 mark_source_rp_bad(ms); 1610 } 1611 1612 trace_source_return_path_thread_end(); 1613 out: 1614 ms->rp_state.from_dst_file = NULL; 1615 qemu_fclose(rp); 1616 return NULL; 1617 } 1618 1619 static int open_return_path_on_source(MigrationState *ms) 1620 { 1621 1622 ms->rp_state.from_dst_file = qemu_file_get_return_path(ms->to_dst_file); 1623 if (!ms->rp_state.from_dst_file) { 1624 return -1; 1625 } 1626 1627 trace_open_return_path_on_source(); 1628 qemu_thread_create(&ms->rp_state.rp_thread, "return path", 1629 source_return_path_thread, ms, QEMU_THREAD_JOINABLE); 1630 1631 trace_open_return_path_on_source_continue(); 1632 1633 return 0; 1634 } 1635 1636 /* Returns 0 if the RP was ok, otherwise there was an error on the RP */ 1637 static int await_return_path_close_on_source(MigrationState *ms) 1638 { 1639 /* 1640 * If this is a normal exit then the destination will send a SHUT and the 1641 * rp_thread will exit, however if there's an error we need to cause 1642 * it to exit. 1643 */ 1644 if (qemu_file_get_error(ms->to_dst_file) && ms->rp_state.from_dst_file) { 1645 /* 1646 * shutdown(2), if we have it, will cause it to unblock if it's stuck 1647 * waiting for the destination. 1648 */ 1649 qemu_file_shutdown(ms->rp_state.from_dst_file); 1650 mark_source_rp_bad(ms); 1651 } 1652 trace_await_return_path_close_on_source_joining(); 1653 qemu_thread_join(&ms->rp_state.rp_thread); 1654 trace_await_return_path_close_on_source_close(); 1655 return ms->rp_state.error; 1656 } 1657 1658 /* 1659 * Switch from normal iteration to postcopy 1660 * Returns non-0 on error 1661 */ 1662 static int postcopy_start(MigrationState *ms, bool *old_vm_running) 1663 { 1664 int ret; 1665 QIOChannelBuffer *bioc; 1666 QEMUFile *fb; 1667 int64_t time_at_stop = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 1668 bool restart_block = false; 1669 migrate_set_state(&ms->state, MIGRATION_STATUS_ACTIVE, 1670 MIGRATION_STATUS_POSTCOPY_ACTIVE); 1671 1672 trace_postcopy_start(); 1673 qemu_mutex_lock_iothread(); 1674 trace_postcopy_start_set_run(); 1675 1676 qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER); 1677 *old_vm_running = runstate_is_running(); 1678 global_state_store(); 1679 ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); 1680 if (ret < 0) { 1681 goto fail; 1682 } 1683 1684 ret = bdrv_inactivate_all(); 1685 if (ret < 0) { 1686 goto fail; 1687 } 1688 restart_block = true; 1689 1690 /* 1691 * Cause any non-postcopiable, but iterative devices to 1692 * send out their final data. 1693 */ 1694 qemu_savevm_state_complete_precopy(ms->to_dst_file, true); 1695 1696 /* 1697 * in Finish migrate and with the io-lock held everything should 1698 * be quiet, but we've potentially still got dirty pages and we 1699 * need to tell the destination to throw any pages it's already received 1700 * that are dirty 1701 */ 1702 if (ram_postcopy_send_discard_bitmap(ms)) { 1703 error_report("postcopy send discard bitmap failed"); 1704 goto fail; 1705 } 1706 1707 /* 1708 * send rest of state - note things that are doing postcopy 1709 * will notice we're in POSTCOPY_ACTIVE and not actually 1710 * wrap their state up here 1711 */ 1712 qemu_file_set_rate_limit(ms->to_dst_file, INT64_MAX); 1713 /* Ping just for debugging, helps line traces up */ 1714 qemu_savevm_send_ping(ms->to_dst_file, 2); 1715 1716 /* 1717 * While loading the device state we may trigger page transfer 1718 * requests and the fd must be free to process those, and thus 1719 * the destination must read the whole device state off the fd before 1720 * it starts processing it. Unfortunately the ad-hoc migration format 1721 * doesn't allow the destination to know the size to read without fully 1722 * parsing it through each devices load-state code (especially the open 1723 * coded devices that use get/put). 1724 * So we wrap the device state up in a package with a length at the start; 1725 * to do this we use a qemu_buf to hold the whole of the device state. 1726 */ 1727 bioc = qio_channel_buffer_new(4096); 1728 qio_channel_set_name(QIO_CHANNEL(bioc), "migration-postcopy-buffer"); 1729 fb = qemu_fopen_channel_output(QIO_CHANNEL(bioc)); 1730 object_unref(OBJECT(bioc)); 1731 1732 /* 1733 * Make sure the receiver can get incoming pages before we send the rest 1734 * of the state 1735 */ 1736 qemu_savevm_send_postcopy_listen(fb); 1737 1738 qemu_savevm_state_complete_precopy(fb, false); 1739 qemu_savevm_send_ping(fb, 3); 1740 1741 qemu_savevm_send_postcopy_run(fb); 1742 1743 /* <><> end of stuff going into the package */ 1744 1745 /* Last point of recovery; as soon as we send the package the destination 1746 * can open devices and potentially start running. 1747 * Lets just check again we've not got any errors. 1748 */ 1749 ret = qemu_file_get_error(ms->to_dst_file); 1750 if (ret) { 1751 error_report("postcopy_start: Migration stream errored (pre package)"); 1752 goto fail_closefb; 1753 } 1754 1755 restart_block = false; 1756 1757 /* Now send that blob */ 1758 if (qemu_savevm_send_packaged(ms->to_dst_file, bioc->data, bioc->usage)) { 1759 goto fail_closefb; 1760 } 1761 qemu_fclose(fb); 1762 1763 /* Send a notify to give a chance for anything that needs to happen 1764 * at the transition to postcopy and after the device state; in particular 1765 * spice needs to trigger a transition now 1766 */ 1767 ms->postcopy_after_devices = true; 1768 notifier_list_notify(&migration_state_notifiers, ms); 1769 1770 ms->downtime = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) - time_at_stop; 1771 1772 qemu_mutex_unlock_iothread(); 1773 1774 /* 1775 * Although this ping is just for debug, it could potentially be 1776 * used for getting a better measurement of downtime at the source. 1777 */ 1778 qemu_savevm_send_ping(ms->to_dst_file, 4); 1779 1780 if (migrate_release_ram()) { 1781 ram_postcopy_migrated_memory_release(ms); 1782 } 1783 1784 ret = qemu_file_get_error(ms->to_dst_file); 1785 if (ret) { 1786 error_report("postcopy_start: Migration stream errored"); 1787 migrate_set_state(&ms->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, 1788 MIGRATION_STATUS_FAILED); 1789 } 1790 1791 return ret; 1792 1793 fail_closefb: 1794 qemu_fclose(fb); 1795 fail: 1796 migrate_set_state(&ms->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, 1797 MIGRATION_STATUS_FAILED); 1798 if (restart_block) { 1799 /* A failure happened early enough that we know the destination hasn't 1800 * accessed block devices, so we're safe to recover. 1801 */ 1802 Error *local_err = NULL; 1803 1804 bdrv_invalidate_cache_all(&local_err); 1805 if (local_err) { 1806 error_report_err(local_err); 1807 } 1808 } 1809 qemu_mutex_unlock_iothread(); 1810 return -1; 1811 } 1812 1813 /** 1814 * migration_completion: Used by migration_thread when there's not much left. 1815 * The caller 'breaks' the loop when this returns. 1816 * 1817 * @s: Current migration state 1818 * @current_active_state: The migration state we expect to be in 1819 * @*old_vm_running: Pointer to old_vm_running flag 1820 * @*start_time: Pointer to time to update 1821 */ 1822 static void migration_completion(MigrationState *s, int current_active_state, 1823 bool *old_vm_running, 1824 int64_t *start_time) 1825 { 1826 int ret; 1827 1828 if (s->state == MIGRATION_STATUS_ACTIVE) { 1829 qemu_mutex_lock_iothread(); 1830 *start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 1831 qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER); 1832 *old_vm_running = runstate_is_running(); 1833 ret = global_state_store(); 1834 1835 if (!ret) { 1836 ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); 1837 /* 1838 * Don't mark the image with BDRV_O_INACTIVE flag if 1839 * we will go into COLO stage later. 1840 */ 1841 if (ret >= 0 && !migrate_colo_enabled()) { 1842 ret = bdrv_inactivate_all(); 1843 } 1844 if (ret >= 0) { 1845 qemu_file_set_rate_limit(s->to_dst_file, INT64_MAX); 1846 qemu_savevm_state_complete_precopy(s->to_dst_file, false); 1847 s->block_inactive = true; 1848 } 1849 } 1850 qemu_mutex_unlock_iothread(); 1851 1852 if (ret < 0) { 1853 goto fail; 1854 } 1855 } else if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) { 1856 trace_migration_completion_postcopy_end(); 1857 1858 qemu_savevm_state_complete_postcopy(s->to_dst_file); 1859 trace_migration_completion_postcopy_end_after_complete(); 1860 } 1861 1862 /* 1863 * If rp was opened we must clean up the thread before 1864 * cleaning everything else up (since if there are no failures 1865 * it will wait for the destination to send it's status in 1866 * a SHUT command). 1867 * Postcopy opens rp if enabled (even if it's not avtivated) 1868 */ 1869 if (migrate_postcopy_ram()) { 1870 int rp_error; 1871 trace_migration_completion_postcopy_end_before_rp(); 1872 rp_error = await_return_path_close_on_source(s); 1873 trace_migration_completion_postcopy_end_after_rp(rp_error); 1874 if (rp_error) { 1875 goto fail_invalidate; 1876 } 1877 } 1878 1879 if (qemu_file_get_error(s->to_dst_file)) { 1880 trace_migration_completion_file_err(); 1881 goto fail_invalidate; 1882 } 1883 1884 if (!migrate_colo_enabled()) { 1885 migrate_set_state(&s->state, current_active_state, 1886 MIGRATION_STATUS_COMPLETED); 1887 } 1888 1889 return; 1890 1891 fail_invalidate: 1892 /* If not doing postcopy, vm_start() will be called: let's regain 1893 * control on images. 1894 */ 1895 if (s->state == MIGRATION_STATUS_ACTIVE) { 1896 Error *local_err = NULL; 1897 1898 qemu_mutex_lock_iothread(); 1899 bdrv_invalidate_cache_all(&local_err); 1900 if (local_err) { 1901 error_report_err(local_err); 1902 } else { 1903 s->block_inactive = false; 1904 } 1905 qemu_mutex_unlock_iothread(); 1906 } 1907 1908 fail: 1909 migrate_set_state(&s->state, current_active_state, 1910 MIGRATION_STATUS_FAILED); 1911 } 1912 1913 bool migrate_colo_enabled(void) 1914 { 1915 MigrationState *s = migrate_get_current(); 1916 return s->enabled_capabilities[MIGRATION_CAPABILITY_X_COLO]; 1917 } 1918 1919 /* 1920 * Master migration thread on the source VM. 1921 * It drives the migration and pumps the data down the outgoing channel. 1922 */ 1923 static void *migration_thread(void *opaque) 1924 { 1925 MigrationState *s = opaque; 1926 /* Used by the bandwidth calcs, updated later */ 1927 int64_t initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 1928 int64_t setup_start = qemu_clock_get_ms(QEMU_CLOCK_HOST); 1929 int64_t initial_bytes = 0; 1930 /* 1931 * The final stage happens when the remaining data is smaller than 1932 * this threshold; it's calculated from the requested downtime and 1933 * measured bandwidth 1934 */ 1935 int64_t threshold_size = 0; 1936 int64_t start_time = initial_time; 1937 int64_t end_time; 1938 bool old_vm_running = false; 1939 bool entered_postcopy = false; 1940 /* The active state we expect to be in; ACTIVE or POSTCOPY_ACTIVE */ 1941 enum MigrationStatus current_active_state = MIGRATION_STATUS_ACTIVE; 1942 bool enable_colo = migrate_colo_enabled(); 1943 1944 rcu_register_thread(); 1945 1946 qemu_savevm_state_header(s->to_dst_file); 1947 1948 if (migrate_postcopy_ram()) { 1949 /* Now tell the dest that it should open its end so it can reply */ 1950 qemu_savevm_send_open_return_path(s->to_dst_file); 1951 1952 /* And do a ping that will make stuff easier to debug */ 1953 qemu_savevm_send_ping(s->to_dst_file, 1); 1954 1955 /* 1956 * Tell the destination that we *might* want to do postcopy later; 1957 * if the other end can't do postcopy it should fail now, nice and 1958 * early. 1959 */ 1960 qemu_savevm_send_postcopy_advise(s->to_dst_file); 1961 } 1962 1963 qemu_savevm_state_begin(s->to_dst_file); 1964 1965 s->setup_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) - setup_start; 1966 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP, 1967 MIGRATION_STATUS_ACTIVE); 1968 1969 trace_migration_thread_setup_complete(); 1970 1971 while (s->state == MIGRATION_STATUS_ACTIVE || 1972 s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) { 1973 int64_t current_time; 1974 uint64_t pending_size; 1975 1976 if (!qemu_file_rate_limit(s->to_dst_file)) { 1977 uint64_t pend_post, pend_nonpost; 1978 1979 qemu_savevm_state_pending(s->to_dst_file, threshold_size, 1980 &pend_nonpost, &pend_post); 1981 pending_size = pend_nonpost + pend_post; 1982 trace_migrate_pending(pending_size, threshold_size, 1983 pend_post, pend_nonpost); 1984 if (pending_size && pending_size >= threshold_size) { 1985 /* Still a significant amount to transfer */ 1986 1987 if (migrate_postcopy_ram() && 1988 s->state != MIGRATION_STATUS_POSTCOPY_ACTIVE && 1989 pend_nonpost <= threshold_size && 1990 atomic_read(&s->start_postcopy)) { 1991 1992 if (!postcopy_start(s, &old_vm_running)) { 1993 current_active_state = MIGRATION_STATUS_POSTCOPY_ACTIVE; 1994 entered_postcopy = true; 1995 } 1996 1997 continue; 1998 } 1999 /* Just another iteration step */ 2000 qemu_savevm_state_iterate(s->to_dst_file, entered_postcopy); 2001 } else { 2002 trace_migration_thread_low_pending(pending_size); 2003 migration_completion(s, current_active_state, 2004 &old_vm_running, &start_time); 2005 break; 2006 } 2007 } 2008 2009 if (qemu_file_get_error(s->to_dst_file)) { 2010 migrate_set_state(&s->state, current_active_state, 2011 MIGRATION_STATUS_FAILED); 2012 trace_migration_thread_file_err(); 2013 break; 2014 } 2015 current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 2016 if (current_time >= initial_time + BUFFER_DELAY) { 2017 uint64_t transferred_bytes = qemu_ftell(s->to_dst_file) - 2018 initial_bytes; 2019 uint64_t time_spent = current_time - initial_time; 2020 double bandwidth = (double)transferred_bytes / time_spent; 2021 threshold_size = bandwidth * s->parameters.downtime_limit; 2022 2023 s->mbps = (((double) transferred_bytes * 8.0) / 2024 ((double) time_spent / 1000.0)) / 1000.0 / 1000.0; 2025 2026 trace_migrate_transferred(transferred_bytes, time_spent, 2027 bandwidth, threshold_size); 2028 /* if we haven't sent anything, we don't want to recalculate 2029 10000 is a small enough number for our purposes */ 2030 if (ram_dirty_pages_rate() && transferred_bytes > 10000) { 2031 s->expected_downtime = ram_dirty_pages_rate() * 2032 qemu_target_page_size() / bandwidth; 2033 } 2034 2035 qemu_file_reset_rate_limit(s->to_dst_file); 2036 initial_time = current_time; 2037 initial_bytes = qemu_ftell(s->to_dst_file); 2038 } 2039 if (qemu_file_rate_limit(s->to_dst_file)) { 2040 /* usleep expects microseconds */ 2041 g_usleep((initial_time + BUFFER_DELAY - current_time)*1000); 2042 } 2043 } 2044 2045 trace_migration_thread_after_loop(); 2046 /* If we enabled cpu throttling for auto-converge, turn it off. */ 2047 cpu_throttle_stop(); 2048 end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 2049 2050 qemu_mutex_lock_iothread(); 2051 /* 2052 * The resource has been allocated by migration will be reused in COLO 2053 * process, so don't release them. 2054 */ 2055 if (!enable_colo) { 2056 qemu_savevm_state_cleanup(); 2057 } 2058 if (s->state == MIGRATION_STATUS_COMPLETED) { 2059 uint64_t transferred_bytes = qemu_ftell(s->to_dst_file); 2060 s->total_time = end_time - s->total_time; 2061 if (!entered_postcopy) { 2062 s->downtime = end_time - start_time; 2063 } 2064 if (s->total_time) { 2065 s->mbps = (((double) transferred_bytes * 8.0) / 2066 ((double) s->total_time)) / 1000; 2067 } 2068 runstate_set(RUN_STATE_POSTMIGRATE); 2069 } else { 2070 if (s->state == MIGRATION_STATUS_ACTIVE && enable_colo) { 2071 migrate_start_colo_process(s); 2072 qemu_savevm_state_cleanup(); 2073 /* 2074 * Fixme: we will run VM in COLO no matter its old running state. 2075 * After exited COLO, we will keep running. 2076 */ 2077 old_vm_running = true; 2078 } 2079 if (old_vm_running && !entered_postcopy) { 2080 vm_start(); 2081 } else { 2082 if (runstate_check(RUN_STATE_FINISH_MIGRATE)) { 2083 runstate_set(RUN_STATE_POSTMIGRATE); 2084 } 2085 } 2086 } 2087 qemu_bh_schedule(s->cleanup_bh); 2088 qemu_mutex_unlock_iothread(); 2089 2090 rcu_unregister_thread(); 2091 return NULL; 2092 } 2093 2094 void migrate_fd_connect(MigrationState *s) 2095 { 2096 s->expected_downtime = s->parameters.downtime_limit; 2097 s->cleanup_bh = qemu_bh_new(migrate_fd_cleanup, s); 2098 2099 qemu_file_set_blocking(s->to_dst_file, true); 2100 qemu_file_set_rate_limit(s->to_dst_file, 2101 s->parameters.max_bandwidth / XFER_LIMIT_RATIO); 2102 2103 /* Notify before starting migration thread */ 2104 notifier_list_notify(&migration_state_notifiers, s); 2105 2106 /* 2107 * Open the return path; currently for postcopy but other things might 2108 * also want it. 2109 */ 2110 if (migrate_postcopy_ram()) { 2111 if (open_return_path_on_source(s)) { 2112 error_report("Unable to open return-path for postcopy"); 2113 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP, 2114 MIGRATION_STATUS_FAILED); 2115 migrate_fd_cleanup(s); 2116 return; 2117 } 2118 } 2119 2120 migrate_compress_threads_create(); 2121 qemu_thread_create(&s->thread, "live_migration", migration_thread, s, 2122 QEMU_THREAD_JOINABLE); 2123 s->migration_thread_running = true; 2124 } 2125 2126