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