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