1 /* 2 * QEMU System Emulator 3 * 4 * Copyright (c) 2003-2008 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 #include <stdint.h> 25 #include <stdarg.h> 26 #include <stdlib.h> 27 #ifndef _WIN32 28 #include <sys/types.h> 29 #include <sys/mman.h> 30 #endif 31 #include "config.h" 32 #include "monitor/monitor.h" 33 #include "sysemu/sysemu.h" 34 #include "qemu/bitops.h" 35 #include "qemu/bitmap.h" 36 #include "sysemu/arch_init.h" 37 #include "audio/audio.h" 38 #include "hw/i386/pc.h" 39 #include "hw/pci/pci.h" 40 #include "hw/audio/audio.h" 41 #include "sysemu/kvm.h" 42 #include "migration/migration.h" 43 #include "hw/i386/smbios.h" 44 #include "exec/address-spaces.h" 45 #include "hw/audio/pcspk.h" 46 #include "migration/page_cache.h" 47 #include "qemu/config-file.h" 48 #include "qemu/error-report.h" 49 #include "qmp-commands.h" 50 #include "trace.h" 51 #include "exec/cpu-all.h" 52 #include "exec/ram_addr.h" 53 #include "hw/acpi/acpi.h" 54 #include "qemu/host-utils.h" 55 #include "qemu/rcu_queue.h" 56 57 #ifdef DEBUG_ARCH_INIT 58 #define DPRINTF(fmt, ...) \ 59 do { fprintf(stdout, "arch_init: " fmt, ## __VA_ARGS__); } while (0) 60 #else 61 #define DPRINTF(fmt, ...) \ 62 do { } while (0) 63 #endif 64 65 #ifdef TARGET_SPARC 66 int graphic_width = 1024; 67 int graphic_height = 768; 68 int graphic_depth = 8; 69 #else 70 int graphic_width = 800; 71 int graphic_height = 600; 72 int graphic_depth = 32; 73 #endif 74 75 76 #if defined(TARGET_ALPHA) 77 #define QEMU_ARCH QEMU_ARCH_ALPHA 78 #elif defined(TARGET_ARM) 79 #define QEMU_ARCH QEMU_ARCH_ARM 80 #elif defined(TARGET_CRIS) 81 #define QEMU_ARCH QEMU_ARCH_CRIS 82 #elif defined(TARGET_I386) 83 #define QEMU_ARCH QEMU_ARCH_I386 84 #elif defined(TARGET_M68K) 85 #define QEMU_ARCH QEMU_ARCH_M68K 86 #elif defined(TARGET_LM32) 87 #define QEMU_ARCH QEMU_ARCH_LM32 88 #elif defined(TARGET_MICROBLAZE) 89 #define QEMU_ARCH QEMU_ARCH_MICROBLAZE 90 #elif defined(TARGET_MIPS) 91 #define QEMU_ARCH QEMU_ARCH_MIPS 92 #elif defined(TARGET_MOXIE) 93 #define QEMU_ARCH QEMU_ARCH_MOXIE 94 #elif defined(TARGET_OPENRISC) 95 #define QEMU_ARCH QEMU_ARCH_OPENRISC 96 #elif defined(TARGET_PPC) 97 #define QEMU_ARCH QEMU_ARCH_PPC 98 #elif defined(TARGET_S390X) 99 #define QEMU_ARCH QEMU_ARCH_S390X 100 #elif defined(TARGET_SH4) 101 #define QEMU_ARCH QEMU_ARCH_SH4 102 #elif defined(TARGET_SPARC) 103 #define QEMU_ARCH QEMU_ARCH_SPARC 104 #elif defined(TARGET_XTENSA) 105 #define QEMU_ARCH QEMU_ARCH_XTENSA 106 #elif defined(TARGET_UNICORE32) 107 #define QEMU_ARCH QEMU_ARCH_UNICORE32 108 #elif defined(TARGET_TRICORE) 109 #define QEMU_ARCH QEMU_ARCH_TRICORE 110 #endif 111 112 const uint32_t arch_type = QEMU_ARCH; 113 static bool mig_throttle_on; 114 static int dirty_rate_high_cnt; 115 static void check_guest_throttling(void); 116 117 static uint64_t bitmap_sync_count; 118 119 /***********************************************************/ 120 /* ram save/restore */ 121 122 #define RAM_SAVE_FLAG_FULL 0x01 /* Obsolete, not used anymore */ 123 #define RAM_SAVE_FLAG_COMPRESS 0x02 124 #define RAM_SAVE_FLAG_MEM_SIZE 0x04 125 #define RAM_SAVE_FLAG_PAGE 0x08 126 #define RAM_SAVE_FLAG_EOS 0x10 127 #define RAM_SAVE_FLAG_CONTINUE 0x20 128 #define RAM_SAVE_FLAG_XBZRLE 0x40 129 /* 0x80 is reserved in migration.h start with 0x100 next */ 130 131 static struct defconfig_file { 132 const char *filename; 133 /* Indicates it is an user config file (disabled by -no-user-config) */ 134 bool userconfig; 135 } default_config_files[] = { 136 { CONFIG_QEMU_CONFDIR "/qemu.conf", true }, 137 { CONFIG_QEMU_CONFDIR "/target-" TARGET_NAME ".conf", true }, 138 { NULL }, /* end of list */ 139 }; 140 141 static const uint8_t ZERO_TARGET_PAGE[TARGET_PAGE_SIZE]; 142 143 int qemu_read_default_config_files(bool userconfig) 144 { 145 int ret; 146 struct defconfig_file *f; 147 148 for (f = default_config_files; f->filename; f++) { 149 if (!userconfig && f->userconfig) { 150 continue; 151 } 152 ret = qemu_read_config_file(f->filename); 153 if (ret < 0 && ret != -ENOENT) { 154 return ret; 155 } 156 } 157 158 return 0; 159 } 160 161 static inline bool is_zero_range(uint8_t *p, uint64_t size) 162 { 163 return buffer_find_nonzero_offset(p, size) == size; 164 } 165 166 /* struct contains XBZRLE cache and a static page 167 used by the compression */ 168 static struct { 169 /* buffer used for XBZRLE encoding */ 170 uint8_t *encoded_buf; 171 /* buffer for storing page content */ 172 uint8_t *current_buf; 173 /* Cache for XBZRLE, Protected by lock. */ 174 PageCache *cache; 175 QemuMutex lock; 176 } XBZRLE; 177 178 /* buffer used for XBZRLE decoding */ 179 static uint8_t *xbzrle_decoded_buf; 180 181 static void XBZRLE_cache_lock(void) 182 { 183 if (migrate_use_xbzrle()) 184 qemu_mutex_lock(&XBZRLE.lock); 185 } 186 187 static void XBZRLE_cache_unlock(void) 188 { 189 if (migrate_use_xbzrle()) 190 qemu_mutex_unlock(&XBZRLE.lock); 191 } 192 193 /* 194 * called from qmp_migrate_set_cache_size in main thread, possibly while 195 * a migration is in progress. 196 * A running migration maybe using the cache and might finish during this 197 * call, hence changes to the cache are protected by XBZRLE.lock(). 198 */ 199 int64_t xbzrle_cache_resize(int64_t new_size) 200 { 201 PageCache *new_cache; 202 int64_t ret; 203 204 if (new_size < TARGET_PAGE_SIZE) { 205 return -1; 206 } 207 208 XBZRLE_cache_lock(); 209 210 if (XBZRLE.cache != NULL) { 211 if (pow2floor(new_size) == migrate_xbzrle_cache_size()) { 212 goto out_new_size; 213 } 214 new_cache = cache_init(new_size / TARGET_PAGE_SIZE, 215 TARGET_PAGE_SIZE); 216 if (!new_cache) { 217 error_report("Error creating cache"); 218 ret = -1; 219 goto out; 220 } 221 222 cache_fini(XBZRLE.cache); 223 XBZRLE.cache = new_cache; 224 } 225 226 out_new_size: 227 ret = pow2floor(new_size); 228 out: 229 XBZRLE_cache_unlock(); 230 return ret; 231 } 232 233 /* accounting for migration statistics */ 234 typedef struct AccountingInfo { 235 uint64_t dup_pages; 236 uint64_t skipped_pages; 237 uint64_t norm_pages; 238 uint64_t iterations; 239 uint64_t xbzrle_bytes; 240 uint64_t xbzrle_pages; 241 uint64_t xbzrle_cache_miss; 242 double xbzrle_cache_miss_rate; 243 uint64_t xbzrle_overflows; 244 } AccountingInfo; 245 246 static AccountingInfo acct_info; 247 248 static void acct_clear(void) 249 { 250 memset(&acct_info, 0, sizeof(acct_info)); 251 } 252 253 uint64_t dup_mig_bytes_transferred(void) 254 { 255 return acct_info.dup_pages * TARGET_PAGE_SIZE; 256 } 257 258 uint64_t dup_mig_pages_transferred(void) 259 { 260 return acct_info.dup_pages; 261 } 262 263 uint64_t skipped_mig_bytes_transferred(void) 264 { 265 return acct_info.skipped_pages * TARGET_PAGE_SIZE; 266 } 267 268 uint64_t skipped_mig_pages_transferred(void) 269 { 270 return acct_info.skipped_pages; 271 } 272 273 uint64_t norm_mig_bytes_transferred(void) 274 { 275 return acct_info.norm_pages * TARGET_PAGE_SIZE; 276 } 277 278 uint64_t norm_mig_pages_transferred(void) 279 { 280 return acct_info.norm_pages; 281 } 282 283 uint64_t xbzrle_mig_bytes_transferred(void) 284 { 285 return acct_info.xbzrle_bytes; 286 } 287 288 uint64_t xbzrle_mig_pages_transferred(void) 289 { 290 return acct_info.xbzrle_pages; 291 } 292 293 uint64_t xbzrle_mig_pages_cache_miss(void) 294 { 295 return acct_info.xbzrle_cache_miss; 296 } 297 298 double xbzrle_mig_cache_miss_rate(void) 299 { 300 return acct_info.xbzrle_cache_miss_rate; 301 } 302 303 uint64_t xbzrle_mig_pages_overflow(void) 304 { 305 return acct_info.xbzrle_overflows; 306 } 307 308 /* This is the last block that we have visited serching for dirty pages 309 */ 310 static RAMBlock *last_seen_block; 311 /* This is the last block from where we have sent data */ 312 static RAMBlock *last_sent_block; 313 static ram_addr_t last_offset; 314 static unsigned long *migration_bitmap; 315 static uint64_t migration_dirty_pages; 316 static uint32_t last_version; 317 static bool ram_bulk_stage; 318 319 /** 320 * save_page_header: Write page header to wire 321 * 322 * If this is the 1st block, it also writes the block identification 323 * 324 * Returns: Number of bytes written 325 * 326 * @f: QEMUFile where to send the data 327 * @block: block that contains the page we want to send 328 * @offset: offset inside the block for the page 329 * in the lower bits, it contains flags 330 */ 331 static size_t save_page_header(QEMUFile *f, RAMBlock *block, ram_addr_t offset) 332 { 333 size_t size; 334 335 if (block == last_sent_block) { 336 offset |= RAM_SAVE_FLAG_CONTINUE; 337 } 338 339 qemu_put_be64(f, offset); 340 size = 8; 341 342 if (block != last_sent_block) { 343 qemu_put_byte(f, strlen(block->idstr)); 344 qemu_put_buffer(f, (uint8_t *)block->idstr, 345 strlen(block->idstr)); 346 size += 1 + strlen(block->idstr); 347 last_sent_block = block; 348 } 349 return size; 350 } 351 352 /* Update the xbzrle cache to reflect a page that's been sent as all 0. 353 * The important thing is that a stale (not-yet-0'd) page be replaced 354 * by the new data. 355 * As a bonus, if the page wasn't in the cache it gets added so that 356 * when a small write is made into the 0'd page it gets XBZRLE sent 357 */ 358 static void xbzrle_cache_zero_page(ram_addr_t current_addr) 359 { 360 if (ram_bulk_stage || !migrate_use_xbzrle()) { 361 return; 362 } 363 364 /* We don't care if this fails to allocate a new cache page 365 * as long as it updated an old one */ 366 cache_insert(XBZRLE.cache, current_addr, ZERO_TARGET_PAGE, 367 bitmap_sync_count); 368 } 369 370 #define ENCODING_FLAG_XBZRLE 0x1 371 372 /** 373 * save_xbzrle_page: compress and send current page 374 * 375 * Returns: 1 means that we wrote the page 376 * 0 means that page is identical to the one already sent 377 * -1 means that xbzrle would be longer than normal 378 * 379 * @f: QEMUFile where to send the data 380 * @current_data: 381 * @current_addr: 382 * @block: block that contains the page we want to send 383 * @offset: offset inside the block for the page 384 * @last_stage: if we are at the completion stage 385 * @bytes_transferred: increase it with the number of transferred bytes 386 */ 387 static int save_xbzrle_page(QEMUFile *f, uint8_t **current_data, 388 ram_addr_t current_addr, RAMBlock *block, 389 ram_addr_t offset, bool last_stage, 390 uint64_t *bytes_transferred) 391 { 392 int encoded_len = 0, bytes_xbzrle; 393 uint8_t *prev_cached_page; 394 395 if (!cache_is_cached(XBZRLE.cache, current_addr, bitmap_sync_count)) { 396 acct_info.xbzrle_cache_miss++; 397 if (!last_stage) { 398 if (cache_insert(XBZRLE.cache, current_addr, *current_data, 399 bitmap_sync_count) == -1) { 400 return -1; 401 } else { 402 /* update *current_data when the page has been 403 inserted into cache */ 404 *current_data = get_cached_data(XBZRLE.cache, current_addr); 405 } 406 } 407 return -1; 408 } 409 410 prev_cached_page = get_cached_data(XBZRLE.cache, current_addr); 411 412 /* save current buffer into memory */ 413 memcpy(XBZRLE.current_buf, *current_data, TARGET_PAGE_SIZE); 414 415 /* XBZRLE encoding (if there is no overflow) */ 416 encoded_len = xbzrle_encode_buffer(prev_cached_page, XBZRLE.current_buf, 417 TARGET_PAGE_SIZE, XBZRLE.encoded_buf, 418 TARGET_PAGE_SIZE); 419 if (encoded_len == 0) { 420 DPRINTF("Skipping unmodified page\n"); 421 return 0; 422 } else if (encoded_len == -1) { 423 DPRINTF("Overflow\n"); 424 acct_info.xbzrle_overflows++; 425 /* update data in the cache */ 426 if (!last_stage) { 427 memcpy(prev_cached_page, *current_data, TARGET_PAGE_SIZE); 428 *current_data = prev_cached_page; 429 } 430 return -1; 431 } 432 433 /* we need to update the data in the cache, in order to get the same data */ 434 if (!last_stage) { 435 memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE); 436 } 437 438 /* Send XBZRLE based compressed page */ 439 bytes_xbzrle = save_page_header(f, block, offset | RAM_SAVE_FLAG_XBZRLE); 440 qemu_put_byte(f, ENCODING_FLAG_XBZRLE); 441 qemu_put_be16(f, encoded_len); 442 qemu_put_buffer(f, XBZRLE.encoded_buf, encoded_len); 443 bytes_xbzrle += encoded_len + 1 + 2; 444 acct_info.xbzrle_pages++; 445 acct_info.xbzrle_bytes += bytes_xbzrle; 446 *bytes_transferred += bytes_xbzrle; 447 448 return 1; 449 } 450 451 static inline 452 ram_addr_t migration_bitmap_find_and_reset_dirty(MemoryRegion *mr, 453 ram_addr_t start) 454 { 455 unsigned long base = mr->ram_addr >> TARGET_PAGE_BITS; 456 unsigned long nr = base + (start >> TARGET_PAGE_BITS); 457 uint64_t mr_size = TARGET_PAGE_ALIGN(memory_region_size(mr)); 458 unsigned long size = base + (mr_size >> TARGET_PAGE_BITS); 459 460 unsigned long next; 461 462 if (ram_bulk_stage && nr > base) { 463 next = nr + 1; 464 } else { 465 next = find_next_bit(migration_bitmap, size, nr); 466 } 467 468 if (next < size) { 469 clear_bit(next, migration_bitmap); 470 migration_dirty_pages--; 471 } 472 return (next - base) << TARGET_PAGE_BITS; 473 } 474 475 static inline bool migration_bitmap_set_dirty(ram_addr_t addr) 476 { 477 bool ret; 478 int nr = addr >> TARGET_PAGE_BITS; 479 480 ret = test_and_set_bit(nr, migration_bitmap); 481 482 if (!ret) { 483 migration_dirty_pages++; 484 } 485 return ret; 486 } 487 488 static void migration_bitmap_sync_range(ram_addr_t start, ram_addr_t length) 489 { 490 ram_addr_t addr; 491 unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS); 492 493 /* start address is aligned at the start of a word? */ 494 if (((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) { 495 int k; 496 int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS); 497 unsigned long *src = ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION]; 498 499 for (k = page; k < page + nr; k++) { 500 if (src[k]) { 501 unsigned long new_dirty; 502 new_dirty = ~migration_bitmap[k]; 503 migration_bitmap[k] |= src[k]; 504 new_dirty &= src[k]; 505 migration_dirty_pages += ctpopl(new_dirty); 506 src[k] = 0; 507 } 508 } 509 } else { 510 for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) { 511 if (cpu_physical_memory_get_dirty(start + addr, 512 TARGET_PAGE_SIZE, 513 DIRTY_MEMORY_MIGRATION)) { 514 cpu_physical_memory_reset_dirty(start + addr, 515 TARGET_PAGE_SIZE, 516 DIRTY_MEMORY_MIGRATION); 517 migration_bitmap_set_dirty(start + addr); 518 } 519 } 520 } 521 } 522 523 524 /* Fix me: there are too many global variables used in migration process. */ 525 static int64_t start_time; 526 static int64_t bytes_xfer_prev; 527 static int64_t num_dirty_pages_period; 528 529 static void migration_bitmap_sync_init(void) 530 { 531 start_time = 0; 532 bytes_xfer_prev = 0; 533 num_dirty_pages_period = 0; 534 } 535 536 /* Called with iothread lock held, to protect ram_list.dirty_memory[] */ 537 static void migration_bitmap_sync(void) 538 { 539 RAMBlock *block; 540 uint64_t num_dirty_pages_init = migration_dirty_pages; 541 MigrationState *s = migrate_get_current(); 542 int64_t end_time; 543 int64_t bytes_xfer_now; 544 static uint64_t xbzrle_cache_miss_prev; 545 static uint64_t iterations_prev; 546 547 bitmap_sync_count++; 548 549 if (!bytes_xfer_prev) { 550 bytes_xfer_prev = ram_bytes_transferred(); 551 } 552 553 if (!start_time) { 554 start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 555 } 556 557 trace_migration_bitmap_sync_start(); 558 address_space_sync_dirty_bitmap(&address_space_memory); 559 560 rcu_read_lock(); 561 QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { 562 migration_bitmap_sync_range(block->mr->ram_addr, block->used_length); 563 } 564 rcu_read_unlock(); 565 566 trace_migration_bitmap_sync_end(migration_dirty_pages 567 - num_dirty_pages_init); 568 num_dirty_pages_period += migration_dirty_pages - num_dirty_pages_init; 569 end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 570 571 /* more than 1 second = 1000 millisecons */ 572 if (end_time > start_time + 1000) { 573 if (migrate_auto_converge()) { 574 /* The following detection logic can be refined later. For now: 575 Check to see if the dirtied bytes is 50% more than the approx. 576 amount of bytes that just got transferred since the last time we 577 were in this routine. If that happens >N times (for now N==4) 578 we turn on the throttle down logic */ 579 bytes_xfer_now = ram_bytes_transferred(); 580 if (s->dirty_pages_rate && 581 (num_dirty_pages_period * TARGET_PAGE_SIZE > 582 (bytes_xfer_now - bytes_xfer_prev)/2) && 583 (dirty_rate_high_cnt++ > 4)) { 584 trace_migration_throttle(); 585 mig_throttle_on = true; 586 dirty_rate_high_cnt = 0; 587 } 588 bytes_xfer_prev = bytes_xfer_now; 589 } else { 590 mig_throttle_on = false; 591 } 592 if (migrate_use_xbzrle()) { 593 if (iterations_prev != 0) { 594 acct_info.xbzrle_cache_miss_rate = 595 (double)(acct_info.xbzrle_cache_miss - 596 xbzrle_cache_miss_prev) / 597 (acct_info.iterations - iterations_prev); 598 } 599 iterations_prev = acct_info.iterations; 600 xbzrle_cache_miss_prev = acct_info.xbzrle_cache_miss; 601 } 602 s->dirty_pages_rate = num_dirty_pages_period * 1000 603 / (end_time - start_time); 604 s->dirty_bytes_rate = s->dirty_pages_rate * TARGET_PAGE_SIZE; 605 start_time = end_time; 606 num_dirty_pages_period = 0; 607 s->dirty_sync_count = bitmap_sync_count; 608 } 609 } 610 611 /** 612 * ram_save_page: Send the given page to the stream 613 * 614 * Returns: Number of pages written. 615 * 616 * @f: QEMUFile where to send the data 617 * @block: block that contains the page we want to send 618 * @offset: offset inside the block for the page 619 * @last_stage: if we are at the completion stage 620 * @bytes_transferred: increase it with the number of transferred bytes 621 */ 622 static int ram_save_page(QEMUFile *f, RAMBlock* block, ram_addr_t offset, 623 bool last_stage, uint64_t *bytes_transferred) 624 { 625 int pages = -1; 626 uint64_t bytes_xmit; 627 ram_addr_t current_addr; 628 MemoryRegion *mr = block->mr; 629 uint8_t *p; 630 int ret; 631 bool send_async = true; 632 633 p = memory_region_get_ram_ptr(mr) + offset; 634 635 /* In doubt sent page as normal */ 636 bytes_xmit = 0; 637 ret = ram_control_save_page(f, block->offset, 638 offset, TARGET_PAGE_SIZE, &bytes_xmit); 639 if (bytes_xmit) { 640 *bytes_transferred += bytes_xmit; 641 pages = 1; 642 } 643 644 XBZRLE_cache_lock(); 645 646 current_addr = block->offset + offset; 647 if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { 648 if (ret != RAM_SAVE_CONTROL_DELAYED) { 649 if (bytes_xmit > 0) { 650 acct_info.norm_pages++; 651 } else if (bytes_xmit == 0) { 652 acct_info.dup_pages++; 653 } 654 } 655 } else if (is_zero_range(p, TARGET_PAGE_SIZE)) { 656 acct_info.dup_pages++; 657 *bytes_transferred += save_page_header(f, block, 658 offset | RAM_SAVE_FLAG_COMPRESS); 659 qemu_put_byte(f, 0); 660 *bytes_transferred += 1; 661 pages = 1; 662 /* Must let xbzrle know, otherwise a previous (now 0'd) cached 663 * page would be stale 664 */ 665 xbzrle_cache_zero_page(current_addr); 666 } else if (!ram_bulk_stage && migrate_use_xbzrle()) { 667 pages = save_xbzrle_page(f, &p, current_addr, block, 668 offset, last_stage, bytes_transferred); 669 if (!last_stage) { 670 /* Can't send this cached data async, since the cache page 671 * might get updated before it gets to the wire 672 */ 673 send_async = false; 674 } 675 } 676 677 /* XBZRLE overflow or normal page */ 678 if (pages == -1) { 679 *bytes_transferred += save_page_header(f, block, 680 offset | RAM_SAVE_FLAG_PAGE); 681 if (send_async) { 682 qemu_put_buffer_async(f, p, TARGET_PAGE_SIZE); 683 } else { 684 qemu_put_buffer(f, p, TARGET_PAGE_SIZE); 685 } 686 *bytes_transferred += TARGET_PAGE_SIZE; 687 pages = 1; 688 acct_info.norm_pages++; 689 } 690 691 XBZRLE_cache_unlock(); 692 693 return pages; 694 } 695 696 /** 697 * ram_find_and_save_block: Finds a dirty page and sends it to f 698 * 699 * Called within an RCU critical section. 700 * 701 * Returns: The number of pages written 702 * 0 means no dirty pages 703 * 704 * @f: QEMUFile where to send the data 705 * @last_stage: if we are at the completion stage 706 * @bytes_transferred: increase it with the number of transferred bytes 707 */ 708 709 static int ram_find_and_save_block(QEMUFile *f, bool last_stage, 710 uint64_t *bytes_transferred) 711 { 712 RAMBlock *block = last_seen_block; 713 ram_addr_t offset = last_offset; 714 bool complete_round = false; 715 int pages = 0; 716 MemoryRegion *mr; 717 718 if (!block) 719 block = QLIST_FIRST_RCU(&ram_list.blocks); 720 721 while (true) { 722 mr = block->mr; 723 offset = migration_bitmap_find_and_reset_dirty(mr, offset); 724 if (complete_round && block == last_seen_block && 725 offset >= last_offset) { 726 break; 727 } 728 if (offset >= block->used_length) { 729 offset = 0; 730 block = QLIST_NEXT_RCU(block, next); 731 if (!block) { 732 block = QLIST_FIRST_RCU(&ram_list.blocks); 733 complete_round = true; 734 ram_bulk_stage = false; 735 } 736 } else { 737 pages = ram_save_page(f, block, offset, last_stage, 738 bytes_transferred); 739 740 /* if page is unmodified, continue to the next */ 741 if (pages > 0) { 742 break; 743 } 744 } 745 } 746 747 last_seen_block = block; 748 last_offset = offset; 749 750 return pages; 751 } 752 753 static uint64_t bytes_transferred; 754 755 void acct_update_position(QEMUFile *f, size_t size, bool zero) 756 { 757 uint64_t pages = size / TARGET_PAGE_SIZE; 758 if (zero) { 759 acct_info.dup_pages += pages; 760 } else { 761 acct_info.norm_pages += pages; 762 bytes_transferred += size; 763 qemu_update_position(f, size); 764 } 765 } 766 767 static ram_addr_t ram_save_remaining(void) 768 { 769 return migration_dirty_pages; 770 } 771 772 uint64_t ram_bytes_remaining(void) 773 { 774 return ram_save_remaining() * TARGET_PAGE_SIZE; 775 } 776 777 uint64_t ram_bytes_transferred(void) 778 { 779 return bytes_transferred; 780 } 781 782 uint64_t ram_bytes_total(void) 783 { 784 RAMBlock *block; 785 uint64_t total = 0; 786 787 rcu_read_lock(); 788 QLIST_FOREACH_RCU(block, &ram_list.blocks, next) 789 total += block->used_length; 790 rcu_read_unlock(); 791 return total; 792 } 793 794 void free_xbzrle_decoded_buf(void) 795 { 796 g_free(xbzrle_decoded_buf); 797 xbzrle_decoded_buf = NULL; 798 } 799 800 static void migration_end(void) 801 { 802 if (migration_bitmap) { 803 memory_global_dirty_log_stop(); 804 g_free(migration_bitmap); 805 migration_bitmap = NULL; 806 } 807 808 XBZRLE_cache_lock(); 809 if (XBZRLE.cache) { 810 cache_fini(XBZRLE.cache); 811 g_free(XBZRLE.encoded_buf); 812 g_free(XBZRLE.current_buf); 813 XBZRLE.cache = NULL; 814 XBZRLE.encoded_buf = NULL; 815 XBZRLE.current_buf = NULL; 816 } 817 XBZRLE_cache_unlock(); 818 } 819 820 static void ram_migration_cancel(void *opaque) 821 { 822 migration_end(); 823 } 824 825 static void reset_ram_globals(void) 826 { 827 last_seen_block = NULL; 828 last_sent_block = NULL; 829 last_offset = 0; 830 last_version = ram_list.version; 831 ram_bulk_stage = true; 832 } 833 834 #define MAX_WAIT 50 /* ms, half buffered_file limit */ 835 836 837 /* Each of ram_save_setup, ram_save_iterate and ram_save_complete has 838 * long-running RCU critical section. When rcu-reclaims in the code 839 * start to become numerous it will be necessary to reduce the 840 * granularity of these critical sections. 841 */ 842 843 static int ram_save_setup(QEMUFile *f, void *opaque) 844 { 845 RAMBlock *block; 846 int64_t ram_bitmap_pages; /* Size of bitmap in pages, including gaps */ 847 848 mig_throttle_on = false; 849 dirty_rate_high_cnt = 0; 850 bitmap_sync_count = 0; 851 migration_bitmap_sync_init(); 852 853 if (migrate_use_xbzrle()) { 854 XBZRLE_cache_lock(); 855 XBZRLE.cache = cache_init(migrate_xbzrle_cache_size() / 856 TARGET_PAGE_SIZE, 857 TARGET_PAGE_SIZE); 858 if (!XBZRLE.cache) { 859 XBZRLE_cache_unlock(); 860 error_report("Error creating cache"); 861 return -1; 862 } 863 XBZRLE_cache_unlock(); 864 865 /* We prefer not to abort if there is no memory */ 866 XBZRLE.encoded_buf = g_try_malloc0(TARGET_PAGE_SIZE); 867 if (!XBZRLE.encoded_buf) { 868 error_report("Error allocating encoded_buf"); 869 return -1; 870 } 871 872 XBZRLE.current_buf = g_try_malloc(TARGET_PAGE_SIZE); 873 if (!XBZRLE.current_buf) { 874 error_report("Error allocating current_buf"); 875 g_free(XBZRLE.encoded_buf); 876 XBZRLE.encoded_buf = NULL; 877 return -1; 878 } 879 880 acct_clear(); 881 } 882 883 /* iothread lock needed for ram_list.dirty_memory[] */ 884 qemu_mutex_lock_iothread(); 885 qemu_mutex_lock_ramlist(); 886 rcu_read_lock(); 887 bytes_transferred = 0; 888 reset_ram_globals(); 889 890 ram_bitmap_pages = last_ram_offset() >> TARGET_PAGE_BITS; 891 migration_bitmap = bitmap_new(ram_bitmap_pages); 892 bitmap_set(migration_bitmap, 0, ram_bitmap_pages); 893 894 /* 895 * Count the total number of pages used by ram blocks not including any 896 * gaps due to alignment or unplugs. 897 */ 898 migration_dirty_pages = 0; 899 QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { 900 uint64_t block_pages; 901 902 block_pages = block->used_length >> TARGET_PAGE_BITS; 903 migration_dirty_pages += block_pages; 904 } 905 906 memory_global_dirty_log_start(); 907 migration_bitmap_sync(); 908 qemu_mutex_unlock_ramlist(); 909 qemu_mutex_unlock_iothread(); 910 911 qemu_put_be64(f, ram_bytes_total() | RAM_SAVE_FLAG_MEM_SIZE); 912 913 QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { 914 qemu_put_byte(f, strlen(block->idstr)); 915 qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr)); 916 qemu_put_be64(f, block->used_length); 917 } 918 919 rcu_read_unlock(); 920 921 ram_control_before_iterate(f, RAM_CONTROL_SETUP); 922 ram_control_after_iterate(f, RAM_CONTROL_SETUP); 923 924 qemu_put_be64(f, RAM_SAVE_FLAG_EOS); 925 926 return 0; 927 } 928 929 static int ram_save_iterate(QEMUFile *f, void *opaque) 930 { 931 int ret; 932 int i; 933 int64_t t0; 934 int pages_sent = 0; 935 936 rcu_read_lock(); 937 if (ram_list.version != last_version) { 938 reset_ram_globals(); 939 } 940 941 /* Read version before ram_list.blocks */ 942 smp_rmb(); 943 944 ram_control_before_iterate(f, RAM_CONTROL_ROUND); 945 946 t0 = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); 947 i = 0; 948 while ((ret = qemu_file_rate_limit(f)) == 0) { 949 int pages; 950 951 pages = ram_find_and_save_block(f, false, &bytes_transferred); 952 /* no more pages to sent */ 953 if (pages == 0) { 954 break; 955 } 956 pages_sent += pages; 957 acct_info.iterations++; 958 check_guest_throttling(); 959 /* we want to check in the 1st loop, just in case it was the 1st time 960 and we had to sync the dirty bitmap. 961 qemu_get_clock_ns() is a bit expensive, so we only check each some 962 iterations 963 */ 964 if ((i & 63) == 0) { 965 uint64_t t1 = (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - t0) / 1000000; 966 if (t1 > MAX_WAIT) { 967 DPRINTF("big wait: %" PRIu64 " milliseconds, %d iterations\n", 968 t1, i); 969 break; 970 } 971 } 972 i++; 973 } 974 rcu_read_unlock(); 975 976 /* 977 * Must occur before EOS (or any QEMUFile operation) 978 * because of RDMA protocol. 979 */ 980 ram_control_after_iterate(f, RAM_CONTROL_ROUND); 981 982 qemu_put_be64(f, RAM_SAVE_FLAG_EOS); 983 bytes_transferred += 8; 984 985 ret = qemu_file_get_error(f); 986 if (ret < 0) { 987 return ret; 988 } 989 990 return pages_sent; 991 } 992 993 /* Called with iothread lock */ 994 static int ram_save_complete(QEMUFile *f, void *opaque) 995 { 996 rcu_read_lock(); 997 998 migration_bitmap_sync(); 999 1000 ram_control_before_iterate(f, RAM_CONTROL_FINISH); 1001 1002 /* try transferring iterative blocks of memory */ 1003 1004 /* flush all remaining blocks regardless of rate limiting */ 1005 while (true) { 1006 int pages; 1007 1008 pages = ram_find_and_save_block(f, true, &bytes_transferred); 1009 /* no more blocks to sent */ 1010 if (pages == 0) { 1011 break; 1012 } 1013 } 1014 1015 ram_control_after_iterate(f, RAM_CONTROL_FINISH); 1016 migration_end(); 1017 1018 rcu_read_unlock(); 1019 qemu_put_be64(f, RAM_SAVE_FLAG_EOS); 1020 1021 return 0; 1022 } 1023 1024 static uint64_t ram_save_pending(QEMUFile *f, void *opaque, uint64_t max_size) 1025 { 1026 uint64_t remaining_size; 1027 1028 remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE; 1029 1030 if (remaining_size < max_size) { 1031 qemu_mutex_lock_iothread(); 1032 rcu_read_lock(); 1033 migration_bitmap_sync(); 1034 rcu_read_unlock(); 1035 qemu_mutex_unlock_iothread(); 1036 remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE; 1037 } 1038 return remaining_size; 1039 } 1040 1041 static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host) 1042 { 1043 unsigned int xh_len; 1044 int xh_flags; 1045 1046 if (!xbzrle_decoded_buf) { 1047 xbzrle_decoded_buf = g_malloc(TARGET_PAGE_SIZE); 1048 } 1049 1050 /* extract RLE header */ 1051 xh_flags = qemu_get_byte(f); 1052 xh_len = qemu_get_be16(f); 1053 1054 if (xh_flags != ENCODING_FLAG_XBZRLE) { 1055 error_report("Failed to load XBZRLE page - wrong compression!"); 1056 return -1; 1057 } 1058 1059 if (xh_len > TARGET_PAGE_SIZE) { 1060 error_report("Failed to load XBZRLE page - len overflow!"); 1061 return -1; 1062 } 1063 /* load data and decode */ 1064 qemu_get_buffer(f, xbzrle_decoded_buf, xh_len); 1065 1066 /* decode RLE */ 1067 if (xbzrle_decode_buffer(xbzrle_decoded_buf, xh_len, host, 1068 TARGET_PAGE_SIZE) == -1) { 1069 error_report("Failed to load XBZRLE page - decode error!"); 1070 return -1; 1071 } 1072 1073 return 0; 1074 } 1075 1076 /* Must be called from within a rcu critical section. 1077 * Returns a pointer from within the RCU-protected ram_list. 1078 */ 1079 static inline void *host_from_stream_offset(QEMUFile *f, 1080 ram_addr_t offset, 1081 int flags) 1082 { 1083 static RAMBlock *block = NULL; 1084 char id[256]; 1085 uint8_t len; 1086 1087 if (flags & RAM_SAVE_FLAG_CONTINUE) { 1088 if (!block || block->max_length <= offset) { 1089 error_report("Ack, bad migration stream!"); 1090 return NULL; 1091 } 1092 1093 return memory_region_get_ram_ptr(block->mr) + offset; 1094 } 1095 1096 len = qemu_get_byte(f); 1097 qemu_get_buffer(f, (uint8_t *)id, len); 1098 id[len] = 0; 1099 1100 QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { 1101 if (!strncmp(id, block->idstr, sizeof(id)) && 1102 block->max_length > offset) { 1103 return memory_region_get_ram_ptr(block->mr) + offset; 1104 } 1105 } 1106 1107 error_report("Can't find block %s!", id); 1108 return NULL; 1109 } 1110 1111 /* 1112 * If a page (or a whole RDMA chunk) has been 1113 * determined to be zero, then zap it. 1114 */ 1115 void ram_handle_compressed(void *host, uint8_t ch, uint64_t size) 1116 { 1117 if (ch != 0 || !is_zero_range(host, size)) { 1118 memset(host, ch, size); 1119 } 1120 } 1121 1122 static int ram_load(QEMUFile *f, void *opaque, int version_id) 1123 { 1124 int flags = 0, ret = 0; 1125 static uint64_t seq_iter; 1126 1127 seq_iter++; 1128 1129 if (version_id != 4) { 1130 ret = -EINVAL; 1131 } 1132 1133 /* This RCU critical section can be very long running. 1134 * When RCU reclaims in the code start to become numerous, 1135 * it will be necessary to reduce the granularity of this 1136 * critical section. 1137 */ 1138 rcu_read_lock(); 1139 while (!ret && !(flags & RAM_SAVE_FLAG_EOS)) { 1140 ram_addr_t addr, total_ram_bytes; 1141 void *host; 1142 uint8_t ch; 1143 1144 addr = qemu_get_be64(f); 1145 flags = addr & ~TARGET_PAGE_MASK; 1146 addr &= TARGET_PAGE_MASK; 1147 1148 switch (flags & ~RAM_SAVE_FLAG_CONTINUE) { 1149 case RAM_SAVE_FLAG_MEM_SIZE: 1150 /* Synchronize RAM block list */ 1151 total_ram_bytes = addr; 1152 while (!ret && total_ram_bytes) { 1153 RAMBlock *block; 1154 uint8_t len; 1155 char id[256]; 1156 ram_addr_t length; 1157 1158 len = qemu_get_byte(f); 1159 qemu_get_buffer(f, (uint8_t *)id, len); 1160 id[len] = 0; 1161 length = qemu_get_be64(f); 1162 1163 QLIST_FOREACH_RCU(block, &ram_list.blocks, next) { 1164 if (!strncmp(id, block->idstr, sizeof(id))) { 1165 if (length != block->used_length) { 1166 Error *local_err = NULL; 1167 1168 ret = qemu_ram_resize(block->offset, length, &local_err); 1169 if (local_err) { 1170 error_report_err(local_err); 1171 } 1172 } 1173 break; 1174 } 1175 } 1176 1177 if (!block) { 1178 error_report("Unknown ramblock \"%s\", cannot " 1179 "accept migration", id); 1180 ret = -EINVAL; 1181 } 1182 1183 total_ram_bytes -= length; 1184 } 1185 break; 1186 case RAM_SAVE_FLAG_COMPRESS: 1187 host = host_from_stream_offset(f, addr, flags); 1188 if (!host) { 1189 error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); 1190 ret = -EINVAL; 1191 break; 1192 } 1193 ch = qemu_get_byte(f); 1194 ram_handle_compressed(host, ch, TARGET_PAGE_SIZE); 1195 break; 1196 case RAM_SAVE_FLAG_PAGE: 1197 host = host_from_stream_offset(f, addr, flags); 1198 if (!host) { 1199 error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); 1200 ret = -EINVAL; 1201 break; 1202 } 1203 qemu_get_buffer(f, host, TARGET_PAGE_SIZE); 1204 break; 1205 case RAM_SAVE_FLAG_XBZRLE: 1206 host = host_from_stream_offset(f, addr, flags); 1207 if (!host) { 1208 error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); 1209 ret = -EINVAL; 1210 break; 1211 } 1212 if (load_xbzrle(f, addr, host) < 0) { 1213 error_report("Failed to decompress XBZRLE page at " 1214 RAM_ADDR_FMT, addr); 1215 ret = -EINVAL; 1216 break; 1217 } 1218 break; 1219 case RAM_SAVE_FLAG_EOS: 1220 /* normal exit */ 1221 break; 1222 default: 1223 if (flags & RAM_SAVE_FLAG_HOOK) { 1224 ram_control_load_hook(f, flags); 1225 } else { 1226 error_report("Unknown combination of migration flags: %#x", 1227 flags); 1228 ret = -EINVAL; 1229 } 1230 } 1231 if (!ret) { 1232 ret = qemu_file_get_error(f); 1233 } 1234 } 1235 1236 rcu_read_unlock(); 1237 DPRINTF("Completed load of VM with exit code %d seq iteration " 1238 "%" PRIu64 "\n", ret, seq_iter); 1239 return ret; 1240 } 1241 1242 static SaveVMHandlers savevm_ram_handlers = { 1243 .save_live_setup = ram_save_setup, 1244 .save_live_iterate = ram_save_iterate, 1245 .save_live_complete = ram_save_complete, 1246 .save_live_pending = ram_save_pending, 1247 .load_state = ram_load, 1248 .cancel = ram_migration_cancel, 1249 }; 1250 1251 void ram_mig_init(void) 1252 { 1253 qemu_mutex_init(&XBZRLE.lock); 1254 register_savevm_live(NULL, "ram", 0, 4, &savevm_ram_handlers, NULL); 1255 } 1256 1257 struct soundhw { 1258 const char *name; 1259 const char *descr; 1260 int enabled; 1261 int isa; 1262 union { 1263 int (*init_isa) (ISABus *bus); 1264 int (*init_pci) (PCIBus *bus); 1265 } init; 1266 }; 1267 1268 static struct soundhw soundhw[9]; 1269 static int soundhw_count; 1270 1271 void isa_register_soundhw(const char *name, const char *descr, 1272 int (*init_isa)(ISABus *bus)) 1273 { 1274 assert(soundhw_count < ARRAY_SIZE(soundhw) - 1); 1275 soundhw[soundhw_count].name = name; 1276 soundhw[soundhw_count].descr = descr; 1277 soundhw[soundhw_count].isa = 1; 1278 soundhw[soundhw_count].init.init_isa = init_isa; 1279 soundhw_count++; 1280 } 1281 1282 void pci_register_soundhw(const char *name, const char *descr, 1283 int (*init_pci)(PCIBus *bus)) 1284 { 1285 assert(soundhw_count < ARRAY_SIZE(soundhw) - 1); 1286 soundhw[soundhw_count].name = name; 1287 soundhw[soundhw_count].descr = descr; 1288 soundhw[soundhw_count].isa = 0; 1289 soundhw[soundhw_count].init.init_pci = init_pci; 1290 soundhw_count++; 1291 } 1292 1293 void select_soundhw(const char *optarg) 1294 { 1295 struct soundhw *c; 1296 1297 if (is_help_option(optarg)) { 1298 show_valid_cards: 1299 1300 if (soundhw_count) { 1301 printf("Valid sound card names (comma separated):\n"); 1302 for (c = soundhw; c->name; ++c) { 1303 printf ("%-11s %s\n", c->name, c->descr); 1304 } 1305 printf("\n-soundhw all will enable all of the above\n"); 1306 } else { 1307 printf("Machine has no user-selectable audio hardware " 1308 "(it may or may not have always-present audio hardware).\n"); 1309 } 1310 exit(!is_help_option(optarg)); 1311 } 1312 else { 1313 size_t l; 1314 const char *p; 1315 char *e; 1316 int bad_card = 0; 1317 1318 if (!strcmp(optarg, "all")) { 1319 for (c = soundhw; c->name; ++c) { 1320 c->enabled = 1; 1321 } 1322 return; 1323 } 1324 1325 p = optarg; 1326 while (*p) { 1327 e = strchr(p, ','); 1328 l = !e ? strlen(p) : (size_t) (e - p); 1329 1330 for (c = soundhw; c->name; ++c) { 1331 if (!strncmp(c->name, p, l) && !c->name[l]) { 1332 c->enabled = 1; 1333 break; 1334 } 1335 } 1336 1337 if (!c->name) { 1338 if (l > 80) { 1339 error_report("Unknown sound card name (too big to show)"); 1340 } 1341 else { 1342 error_report("Unknown sound card name `%.*s'", 1343 (int) l, p); 1344 } 1345 bad_card = 1; 1346 } 1347 p += l + (e != NULL); 1348 } 1349 1350 if (bad_card) { 1351 goto show_valid_cards; 1352 } 1353 } 1354 } 1355 1356 void audio_init(void) 1357 { 1358 struct soundhw *c; 1359 ISABus *isa_bus = (ISABus *) object_resolve_path_type("", TYPE_ISA_BUS, NULL); 1360 PCIBus *pci_bus = (PCIBus *) object_resolve_path_type("", TYPE_PCI_BUS, NULL); 1361 1362 for (c = soundhw; c->name; ++c) { 1363 if (c->enabled) { 1364 if (c->isa) { 1365 if (!isa_bus) { 1366 error_report("ISA bus not available for %s", c->name); 1367 exit(1); 1368 } 1369 c->init.init_isa(isa_bus); 1370 } else { 1371 if (!pci_bus) { 1372 error_report("PCI bus not available for %s", c->name); 1373 exit(1); 1374 } 1375 c->init.init_pci(pci_bus); 1376 } 1377 } 1378 } 1379 } 1380 1381 int qemu_uuid_parse(const char *str, uint8_t *uuid) 1382 { 1383 int ret; 1384 1385 if (strlen(str) != 36) { 1386 return -1; 1387 } 1388 1389 ret = sscanf(str, UUID_FMT, &uuid[0], &uuid[1], &uuid[2], &uuid[3], 1390 &uuid[4], &uuid[5], &uuid[6], &uuid[7], &uuid[8], &uuid[9], 1391 &uuid[10], &uuid[11], &uuid[12], &uuid[13], &uuid[14], 1392 &uuid[15]); 1393 1394 if (ret != 16) { 1395 return -1; 1396 } 1397 return 0; 1398 } 1399 1400 void do_acpitable_option(const QemuOpts *opts) 1401 { 1402 #ifdef TARGET_I386 1403 Error *err = NULL; 1404 1405 acpi_table_add(opts, &err); 1406 if (err) { 1407 error_report("Wrong acpi table provided: %s", 1408 error_get_pretty(err)); 1409 error_free(err); 1410 exit(1); 1411 } 1412 #endif 1413 } 1414 1415 void do_smbios_option(QemuOpts *opts) 1416 { 1417 #ifdef TARGET_I386 1418 smbios_entry_add(opts); 1419 #endif 1420 } 1421 1422 void cpudef_init(void) 1423 { 1424 #if defined(cpudef_setup) 1425 cpudef_setup(); /* parse cpu definitions in target config file */ 1426 #endif 1427 } 1428 1429 int kvm_available(void) 1430 { 1431 #ifdef CONFIG_KVM 1432 return 1; 1433 #else 1434 return 0; 1435 #endif 1436 } 1437 1438 int xen_available(void) 1439 { 1440 #ifdef CONFIG_XEN 1441 return 1; 1442 #else 1443 return 0; 1444 #endif 1445 } 1446 1447 1448 TargetInfo *qmp_query_target(Error **errp) 1449 { 1450 TargetInfo *info = g_malloc0(sizeof(*info)); 1451 1452 info->arch = g_strdup(TARGET_NAME); 1453 1454 return info; 1455 } 1456 1457 /* Stub function that's gets run on the vcpu when its brought out of the 1458 VM to run inside qemu via async_run_on_cpu()*/ 1459 static void mig_sleep_cpu(void *opq) 1460 { 1461 qemu_mutex_unlock_iothread(); 1462 g_usleep(30*1000); 1463 qemu_mutex_lock_iothread(); 1464 } 1465 1466 /* To reduce the dirty rate explicitly disallow the VCPUs from spending 1467 much time in the VM. The migration thread will try to catchup. 1468 Workload will experience a performance drop. 1469 */ 1470 static void mig_throttle_guest_down(void) 1471 { 1472 CPUState *cpu; 1473 1474 qemu_mutex_lock_iothread(); 1475 CPU_FOREACH(cpu) { 1476 async_run_on_cpu(cpu, mig_sleep_cpu, NULL); 1477 } 1478 qemu_mutex_unlock_iothread(); 1479 } 1480 1481 static void check_guest_throttling(void) 1482 { 1483 static int64_t t0; 1484 int64_t t1; 1485 1486 if (!mig_throttle_on) { 1487 return; 1488 } 1489 1490 if (!t0) { 1491 t0 = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); 1492 return; 1493 } 1494 1495 t1 = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); 1496 1497 /* If it has been more than 40 ms since the last time the guest 1498 * was throttled then do it again. 1499 */ 1500 if (40 < (t1-t0)/1000000) { 1501 mig_throttle_guest_down(); 1502 t0 = t1; 1503 } 1504 } 1505