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