1 /* 2 * Dirtyrate implement code 3 * 4 * Copyright (c) 2020 HUAWEI TECHNOLOGIES CO.,LTD. 5 * 6 * Authors: 7 * Chuan Zheng <zhengchuan@huawei.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2 or later. 10 * See the COPYING file in the top-level directory. 11 */ 12 13 #include "qemu/osdep.h" 14 #include "qemu/error-report.h" 15 #include "hw/core/cpu.h" 16 #include "qapi/error.h" 17 #include "exec/ramblock.h" 18 #include "exec/target_page.h" 19 #include "qemu/rcu_queue.h" 20 #include "qemu/main-loop.h" 21 #include "qapi/qapi-commands-migration.h" 22 #include "ram.h" 23 #include "trace.h" 24 #include "dirtyrate.h" 25 #include "monitor/hmp.h" 26 #include "monitor/monitor.h" 27 #include "qapi/qmp/qdict.h" 28 #include "sysemu/kvm.h" 29 #include "sysemu/runstate.h" 30 #include "exec/memory.h" 31 #include "qemu/xxhash.h" 32 #include "migration.h" 33 34 /* 35 * total_dirty_pages is procted by BQL and is used 36 * to stat dirty pages during the period of two 37 * memory_global_dirty_log_sync 38 */ 39 uint64_t total_dirty_pages; 40 41 typedef struct DirtyPageRecord { 42 uint64_t start_pages; 43 uint64_t end_pages; 44 } DirtyPageRecord; 45 46 static int CalculatingState = DIRTY_RATE_STATUS_UNSTARTED; 47 static struct DirtyRateStat DirtyStat; 48 static DirtyRateMeasureMode dirtyrate_mode = 49 DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING; 50 51 static int64_t dirty_stat_wait(int64_t msec, int64_t initial_time) 52 { 53 int64_t current_time; 54 55 current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 56 if ((current_time - initial_time) >= msec) { 57 msec = current_time - initial_time; 58 } else { 59 g_usleep((msec + initial_time - current_time) * 1000); 60 /* g_usleep may overshoot */ 61 msec = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) - initial_time; 62 } 63 64 return msec; 65 } 66 67 static inline void record_dirtypages(DirtyPageRecord *dirty_pages, 68 CPUState *cpu, bool start) 69 { 70 if (start) { 71 dirty_pages[cpu->cpu_index].start_pages = cpu->dirty_pages; 72 } else { 73 dirty_pages[cpu->cpu_index].end_pages = cpu->dirty_pages; 74 } 75 } 76 77 static int64_t do_calculate_dirtyrate(DirtyPageRecord dirty_pages, 78 int64_t calc_time_ms) 79 { 80 uint64_t increased_dirty_pages = 81 dirty_pages.end_pages - dirty_pages.start_pages; 82 83 /* 84 * multiply by 1000ms/s _before_ converting down to megabytes 85 * to avoid losing precision 86 */ 87 return qemu_target_pages_to_MiB(increased_dirty_pages * 1000) / 88 calc_time_ms; 89 } 90 91 void global_dirty_log_change(unsigned int flag, bool start) 92 { 93 Error *local_err = NULL; 94 bool ret; 95 96 bql_lock(); 97 if (start) { 98 ret = memory_global_dirty_log_start(flag, &local_err); 99 if (!ret) { 100 error_report_err(local_err); 101 } 102 } else { 103 memory_global_dirty_log_stop(flag); 104 } 105 bql_unlock(); 106 } 107 108 /* 109 * global_dirty_log_sync 110 * 1. sync dirty log from kvm 111 * 2. stop dirty tracking if needed. 112 */ 113 static void global_dirty_log_sync(unsigned int flag, bool one_shot) 114 { 115 bql_lock(); 116 memory_global_dirty_log_sync(false); 117 if (one_shot) { 118 memory_global_dirty_log_stop(flag); 119 } 120 bql_unlock(); 121 } 122 123 static DirtyPageRecord *vcpu_dirty_stat_alloc(VcpuStat *stat) 124 { 125 CPUState *cpu; 126 int nvcpu = 0; 127 128 CPU_FOREACH(cpu) { 129 nvcpu++; 130 } 131 132 stat->nvcpu = nvcpu; 133 stat->rates = g_new0(DirtyRateVcpu, nvcpu); 134 135 return g_new0(DirtyPageRecord, nvcpu); 136 } 137 138 static void vcpu_dirty_stat_collect(DirtyPageRecord *records, 139 bool start) 140 { 141 CPUState *cpu; 142 143 CPU_FOREACH(cpu) { 144 record_dirtypages(records, cpu, start); 145 } 146 } 147 148 int64_t vcpu_calculate_dirtyrate(int64_t calc_time_ms, 149 VcpuStat *stat, 150 unsigned int flag, 151 bool one_shot) 152 { 153 DirtyPageRecord *records = NULL; 154 int64_t init_time_ms; 155 int64_t duration; 156 int64_t dirtyrate; 157 int i = 0; 158 unsigned int gen_id = 0; 159 160 retry: 161 init_time_ms = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 162 163 WITH_QEMU_LOCK_GUARD(&qemu_cpu_list_lock) { 164 gen_id = cpu_list_generation_id_get(); 165 records = vcpu_dirty_stat_alloc(stat); 166 vcpu_dirty_stat_collect(records, true); 167 } 168 169 duration = dirty_stat_wait(calc_time_ms, init_time_ms); 170 171 global_dirty_log_sync(flag, one_shot); 172 173 WITH_QEMU_LOCK_GUARD(&qemu_cpu_list_lock) { 174 if (gen_id != cpu_list_generation_id_get()) { 175 g_free(records); 176 g_free(stat->rates); 177 cpu_list_unlock(); 178 goto retry; 179 } 180 vcpu_dirty_stat_collect(records, false); 181 } 182 183 for (i = 0; i < stat->nvcpu; i++) { 184 dirtyrate = do_calculate_dirtyrate(records[i], duration); 185 186 stat->rates[i].id = i; 187 stat->rates[i].dirty_rate = dirtyrate; 188 189 trace_dirtyrate_do_calculate_vcpu(i, dirtyrate); 190 } 191 192 g_free(records); 193 194 return duration; 195 } 196 197 static bool is_calc_time_valid(int64_t msec) 198 { 199 if ((msec < MIN_CALC_TIME_MS) || (msec > MAX_CALC_TIME_MS)) { 200 return false; 201 } 202 203 return true; 204 } 205 206 static bool is_sample_pages_valid(int64_t pages) 207 { 208 return pages >= MIN_SAMPLE_PAGE_COUNT && 209 pages <= MAX_SAMPLE_PAGE_COUNT; 210 } 211 212 static int dirtyrate_set_state(int *state, int old_state, int new_state) 213 { 214 assert(new_state < DIRTY_RATE_STATUS__MAX); 215 trace_dirtyrate_set_state(DirtyRateStatus_str(new_state)); 216 if (qatomic_cmpxchg(state, old_state, new_state) == old_state) { 217 return 0; 218 } else { 219 return -1; 220 } 221 } 222 223 /* Decimal power of given time unit relative to one second */ 224 static int time_unit_to_power(TimeUnit time_unit) 225 { 226 switch (time_unit) { 227 case TIME_UNIT_SECOND: 228 return 0; 229 case TIME_UNIT_MILLISECOND: 230 return -3; 231 default: 232 g_assert_not_reached(); 233 } 234 } 235 236 static int64_t convert_time_unit(int64_t value, TimeUnit unit_from, 237 TimeUnit unit_to) 238 { 239 int power = time_unit_to_power(unit_from) - 240 time_unit_to_power(unit_to); 241 while (power < 0) { 242 value /= 10; 243 power += 1; 244 } 245 while (power > 0) { 246 value *= 10; 247 power -= 1; 248 } 249 return value; 250 } 251 252 253 static struct DirtyRateInfo * 254 query_dirty_rate_info(TimeUnit calc_time_unit) 255 { 256 int i; 257 int64_t dirty_rate = DirtyStat.dirty_rate; 258 struct DirtyRateInfo *info = g_new0(DirtyRateInfo, 1); 259 DirtyRateVcpuList *head = NULL, **tail = &head; 260 261 info->status = CalculatingState; 262 info->start_time = DirtyStat.start_time; 263 info->calc_time = convert_time_unit(DirtyStat.calc_time_ms, 264 TIME_UNIT_MILLISECOND, 265 calc_time_unit); 266 info->calc_time_unit = calc_time_unit; 267 info->sample_pages = DirtyStat.sample_pages; 268 info->mode = dirtyrate_mode; 269 270 if (qatomic_read(&CalculatingState) == DIRTY_RATE_STATUS_MEASURED) { 271 info->has_dirty_rate = true; 272 info->dirty_rate = dirty_rate; 273 274 if (dirtyrate_mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) { 275 /* 276 * set sample_pages with 0 to indicate page sampling 277 * isn't enabled 278 **/ 279 info->sample_pages = 0; 280 info->has_vcpu_dirty_rate = true; 281 for (i = 0; i < DirtyStat.dirty_ring.nvcpu; i++) { 282 DirtyRateVcpu *rate = g_new0(DirtyRateVcpu, 1); 283 rate->id = DirtyStat.dirty_ring.rates[i].id; 284 rate->dirty_rate = DirtyStat.dirty_ring.rates[i].dirty_rate; 285 QAPI_LIST_APPEND(tail, rate); 286 } 287 info->vcpu_dirty_rate = head; 288 } 289 290 if (dirtyrate_mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP) { 291 info->sample_pages = 0; 292 } 293 } 294 295 trace_query_dirty_rate_info(DirtyRateStatus_str(CalculatingState)); 296 297 return info; 298 } 299 300 static void init_dirtyrate_stat(struct DirtyRateConfig config) 301 { 302 DirtyStat.dirty_rate = -1; 303 DirtyStat.start_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) / 1000; 304 DirtyStat.calc_time_ms = config.calc_time_ms; 305 DirtyStat.sample_pages = config.sample_pages_per_gigabytes; 306 307 switch (config.mode) { 308 case DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING: 309 DirtyStat.page_sampling.total_dirty_samples = 0; 310 DirtyStat.page_sampling.total_sample_count = 0; 311 DirtyStat.page_sampling.total_block_mem_MB = 0; 312 break; 313 case DIRTY_RATE_MEASURE_MODE_DIRTY_RING: 314 DirtyStat.dirty_ring.nvcpu = -1; 315 DirtyStat.dirty_ring.rates = NULL; 316 break; 317 default: 318 break; 319 } 320 } 321 322 static void cleanup_dirtyrate_stat(struct DirtyRateConfig config) 323 { 324 /* last calc-dirty-rate qmp use dirty ring mode */ 325 if (dirtyrate_mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) { 326 free(DirtyStat.dirty_ring.rates); 327 DirtyStat.dirty_ring.rates = NULL; 328 } 329 } 330 331 static void update_dirtyrate_stat(struct RamblockDirtyInfo *info) 332 { 333 DirtyStat.page_sampling.total_dirty_samples += info->sample_dirty_count; 334 DirtyStat.page_sampling.total_sample_count += info->sample_pages_count; 335 /* size of total pages in MB */ 336 DirtyStat.page_sampling.total_block_mem_MB += 337 qemu_target_pages_to_MiB(info->ramblock_pages); 338 } 339 340 static void update_dirtyrate(uint64_t msec) 341 { 342 uint64_t dirtyrate; 343 uint64_t total_dirty_samples = DirtyStat.page_sampling.total_dirty_samples; 344 uint64_t total_sample_count = DirtyStat.page_sampling.total_sample_count; 345 uint64_t total_block_mem_MB = DirtyStat.page_sampling.total_block_mem_MB; 346 347 dirtyrate = total_dirty_samples * total_block_mem_MB * 348 1000 / (total_sample_count * msec); 349 350 DirtyStat.dirty_rate = dirtyrate; 351 } 352 353 /* 354 * Compute hash of a single page of size TARGET_PAGE_SIZE. 355 */ 356 static uint32_t compute_page_hash(void *ptr) 357 { 358 size_t page_size = qemu_target_page_size(); 359 uint32_t i; 360 uint64_t v1, v2, v3, v4; 361 uint64_t res; 362 const uint64_t *p = ptr; 363 364 v1 = QEMU_XXHASH_SEED + XXH_PRIME64_1 + XXH_PRIME64_2; 365 v2 = QEMU_XXHASH_SEED + XXH_PRIME64_2; 366 v3 = QEMU_XXHASH_SEED + 0; 367 v4 = QEMU_XXHASH_SEED - XXH_PRIME64_1; 368 for (i = 0; i < page_size / 8; i += 4) { 369 v1 = XXH64_round(v1, p[i + 0]); 370 v2 = XXH64_round(v2, p[i + 1]); 371 v3 = XXH64_round(v3, p[i + 2]); 372 v4 = XXH64_round(v4, p[i + 3]); 373 } 374 res = XXH64_mergerounds(v1, v2, v3, v4); 375 res += page_size; 376 res = XXH64_avalanche(res); 377 return (uint32_t)(res & UINT32_MAX); 378 } 379 380 381 /* 382 * get hash result for the sampled memory with length of TARGET_PAGE_SIZE 383 * in ramblock, which starts from ramblock base address. 384 */ 385 static uint32_t get_ramblock_vfn_hash(struct RamblockDirtyInfo *info, 386 uint64_t vfn) 387 { 388 uint32_t hash; 389 390 hash = compute_page_hash(info->ramblock_addr + 391 vfn * qemu_target_page_size()); 392 393 trace_get_ramblock_vfn_hash(info->idstr, vfn, hash); 394 return hash; 395 } 396 397 static bool save_ramblock_hash(struct RamblockDirtyInfo *info) 398 { 399 unsigned int sample_pages_count; 400 int i; 401 GRand *rand; 402 403 sample_pages_count = info->sample_pages_count; 404 405 /* ramblock size less than one page, return success to skip this ramblock */ 406 if (unlikely(info->ramblock_pages == 0 || sample_pages_count == 0)) { 407 return true; 408 } 409 410 info->hash_result = g_try_malloc0_n(sample_pages_count, 411 sizeof(uint32_t)); 412 if (!info->hash_result) { 413 return false; 414 } 415 416 info->sample_page_vfn = g_try_malloc0_n(sample_pages_count, 417 sizeof(uint64_t)); 418 if (!info->sample_page_vfn) { 419 g_free(info->hash_result); 420 return false; 421 } 422 423 rand = g_rand_new(); 424 for (i = 0; i < sample_pages_count; i++) { 425 info->sample_page_vfn[i] = g_rand_int_range(rand, 0, 426 info->ramblock_pages - 1); 427 info->hash_result[i] = get_ramblock_vfn_hash(info, 428 info->sample_page_vfn[i]); 429 } 430 g_rand_free(rand); 431 432 return true; 433 } 434 435 static void get_ramblock_dirty_info(RAMBlock *block, 436 struct RamblockDirtyInfo *info, 437 struct DirtyRateConfig *config) 438 { 439 uint64_t sample_pages_per_gigabytes = config->sample_pages_per_gigabytes; 440 gsize len; 441 442 /* Right shift 30 bits to calc ramblock size in GB */ 443 info->sample_pages_count = (qemu_ram_get_used_length(block) * 444 sample_pages_per_gigabytes) >> 30; 445 /* Right shift TARGET_PAGE_BITS to calc page count */ 446 info->ramblock_pages = qemu_ram_get_used_length(block) >> 447 qemu_target_page_bits(); 448 info->ramblock_addr = qemu_ram_get_host_addr(block); 449 len = g_strlcpy(info->idstr, qemu_ram_get_idstr(block), 450 sizeof(info->idstr)); 451 g_assert(len < sizeof(info->idstr)); 452 } 453 454 static void free_ramblock_dirty_info(struct RamblockDirtyInfo *infos, int count) 455 { 456 int i; 457 458 if (!infos) { 459 return; 460 } 461 462 for (i = 0; i < count; i++) { 463 g_free(infos[i].sample_page_vfn); 464 g_free(infos[i].hash_result); 465 } 466 g_free(infos); 467 } 468 469 static bool skip_sample_ramblock(RAMBlock *block) 470 { 471 /* 472 * Sample only blocks larger than MIN_RAMBLOCK_SIZE. 473 */ 474 if (qemu_ram_get_used_length(block) < (MIN_RAMBLOCK_SIZE << 10)) { 475 trace_skip_sample_ramblock(block->idstr, 476 qemu_ram_get_used_length(block)); 477 return true; 478 } 479 480 return false; 481 } 482 483 static bool record_ramblock_hash_info(struct RamblockDirtyInfo **block_dinfo, 484 struct DirtyRateConfig config, 485 int *block_count) 486 { 487 struct RamblockDirtyInfo *info = NULL; 488 struct RamblockDirtyInfo *dinfo = NULL; 489 RAMBlock *block = NULL; 490 int total_count = 0; 491 int index = 0; 492 bool ret = false; 493 494 RAMBLOCK_FOREACH_MIGRATABLE(block) { 495 if (skip_sample_ramblock(block)) { 496 continue; 497 } 498 total_count++; 499 } 500 501 dinfo = g_try_malloc0_n(total_count, sizeof(struct RamblockDirtyInfo)); 502 if (dinfo == NULL) { 503 goto out; 504 } 505 506 RAMBLOCK_FOREACH_MIGRATABLE(block) { 507 if (skip_sample_ramblock(block)) { 508 continue; 509 } 510 if (index >= total_count) { 511 break; 512 } 513 info = &dinfo[index]; 514 get_ramblock_dirty_info(block, info, &config); 515 if (!save_ramblock_hash(info)) { 516 goto out; 517 } 518 index++; 519 } 520 ret = true; 521 522 out: 523 *block_count = index; 524 *block_dinfo = dinfo; 525 return ret; 526 } 527 528 static void calc_page_dirty_rate(struct RamblockDirtyInfo *info) 529 { 530 uint32_t hash; 531 int i; 532 533 for (i = 0; i < info->sample_pages_count; i++) { 534 hash = get_ramblock_vfn_hash(info, info->sample_page_vfn[i]); 535 if (hash != info->hash_result[i]) { 536 trace_calc_page_dirty_rate(info->idstr, hash, info->hash_result[i]); 537 info->sample_dirty_count++; 538 } 539 } 540 } 541 542 static struct RamblockDirtyInfo * 543 find_block_matched(RAMBlock *block, int count, 544 struct RamblockDirtyInfo *infos) 545 { 546 int i; 547 548 for (i = 0; i < count; i++) { 549 if (!strcmp(infos[i].idstr, qemu_ram_get_idstr(block))) { 550 break; 551 } 552 } 553 554 if (i == count) { 555 return NULL; 556 } 557 558 if (infos[i].ramblock_addr != qemu_ram_get_host_addr(block) || 559 infos[i].ramblock_pages != 560 (qemu_ram_get_used_length(block) >> qemu_target_page_bits())) { 561 trace_find_page_matched(block->idstr); 562 return NULL; 563 } 564 565 return &infos[i]; 566 } 567 568 static bool compare_page_hash_info(struct RamblockDirtyInfo *info, 569 int block_count) 570 { 571 struct RamblockDirtyInfo *block_dinfo = NULL; 572 RAMBlock *block = NULL; 573 574 RAMBLOCK_FOREACH_MIGRATABLE(block) { 575 if (skip_sample_ramblock(block)) { 576 continue; 577 } 578 block_dinfo = find_block_matched(block, block_count, info); 579 if (block_dinfo == NULL) { 580 continue; 581 } 582 calc_page_dirty_rate(block_dinfo); 583 update_dirtyrate_stat(block_dinfo); 584 } 585 586 if (DirtyStat.page_sampling.total_sample_count == 0) { 587 return false; 588 } 589 590 return true; 591 } 592 593 static inline void record_dirtypages_bitmap(DirtyPageRecord *dirty_pages, 594 bool start) 595 { 596 if (start) { 597 dirty_pages->start_pages = total_dirty_pages; 598 } else { 599 dirty_pages->end_pages = total_dirty_pages; 600 } 601 } 602 603 static inline void dirtyrate_manual_reset_protect(void) 604 { 605 RAMBlock *block = NULL; 606 607 WITH_RCU_READ_LOCK_GUARD() { 608 RAMBLOCK_FOREACH_MIGRATABLE(block) { 609 memory_region_clear_dirty_bitmap(block->mr, 0, 610 block->used_length); 611 } 612 } 613 } 614 615 static void calculate_dirtyrate_dirty_bitmap(struct DirtyRateConfig config) 616 { 617 int64_t start_time; 618 DirtyPageRecord dirty_pages; 619 Error *local_err = NULL; 620 621 bql_lock(); 622 if (!memory_global_dirty_log_start(GLOBAL_DIRTY_DIRTY_RATE, &local_err)) { 623 error_report_err(local_err); 624 } 625 626 /* 627 * 1'round of log sync may return all 1 bits with 628 * KVM_DIRTY_LOG_INITIALLY_SET enable 629 * skip it unconditionally and start dirty tracking 630 * from 2'round of log sync 631 */ 632 memory_global_dirty_log_sync(false); 633 634 /* 635 * reset page protect manually and unconditionally. 636 * this make sure kvm dirty log be cleared if 637 * KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE cap is enabled. 638 */ 639 dirtyrate_manual_reset_protect(); 640 bql_unlock(); 641 642 record_dirtypages_bitmap(&dirty_pages, true); 643 644 start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 645 DirtyStat.start_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) / 1000; 646 647 DirtyStat.calc_time_ms = dirty_stat_wait(config.calc_time_ms, start_time); 648 649 /* 650 * do two things. 651 * 1. fetch dirty bitmap from kvm 652 * 2. stop dirty tracking 653 */ 654 global_dirty_log_sync(GLOBAL_DIRTY_DIRTY_RATE, true); 655 656 record_dirtypages_bitmap(&dirty_pages, false); 657 658 DirtyStat.dirty_rate = do_calculate_dirtyrate(dirty_pages, 659 DirtyStat.calc_time_ms); 660 } 661 662 static void calculate_dirtyrate_dirty_ring(struct DirtyRateConfig config) 663 { 664 uint64_t dirtyrate = 0; 665 uint64_t dirtyrate_sum = 0; 666 int i = 0; 667 668 /* start log sync */ 669 global_dirty_log_change(GLOBAL_DIRTY_DIRTY_RATE, true); 670 671 DirtyStat.start_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) / 1000; 672 673 /* calculate vcpu dirtyrate */ 674 DirtyStat.calc_time_ms = vcpu_calculate_dirtyrate(config.calc_time_ms, 675 &DirtyStat.dirty_ring, 676 GLOBAL_DIRTY_DIRTY_RATE, 677 true); 678 679 /* calculate vm dirtyrate */ 680 for (i = 0; i < DirtyStat.dirty_ring.nvcpu; i++) { 681 dirtyrate = DirtyStat.dirty_ring.rates[i].dirty_rate; 682 DirtyStat.dirty_ring.rates[i].dirty_rate = dirtyrate; 683 dirtyrate_sum += dirtyrate; 684 } 685 686 DirtyStat.dirty_rate = dirtyrate_sum; 687 } 688 689 static void calculate_dirtyrate_sample_vm(struct DirtyRateConfig config) 690 { 691 struct RamblockDirtyInfo *block_dinfo = NULL; 692 int block_count = 0; 693 int64_t initial_time; 694 695 rcu_read_lock(); 696 initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 697 DirtyStat.start_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) / 1000; 698 if (!record_ramblock_hash_info(&block_dinfo, config, &block_count)) { 699 goto out; 700 } 701 rcu_read_unlock(); 702 703 DirtyStat.calc_time_ms = dirty_stat_wait(config.calc_time_ms, 704 initial_time); 705 706 rcu_read_lock(); 707 if (!compare_page_hash_info(block_dinfo, block_count)) { 708 goto out; 709 } 710 711 update_dirtyrate(DirtyStat.calc_time_ms); 712 713 out: 714 rcu_read_unlock(); 715 free_ramblock_dirty_info(block_dinfo, block_count); 716 } 717 718 static void calculate_dirtyrate(struct DirtyRateConfig config) 719 { 720 if (config.mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP) { 721 calculate_dirtyrate_dirty_bitmap(config); 722 } else if (config.mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) { 723 calculate_dirtyrate_dirty_ring(config); 724 } else { 725 calculate_dirtyrate_sample_vm(config); 726 } 727 728 trace_dirtyrate_calculate(DirtyStat.dirty_rate); 729 } 730 731 void *get_dirtyrate_thread(void *arg) 732 { 733 struct DirtyRateConfig config = *(struct DirtyRateConfig *)arg; 734 int ret; 735 rcu_register_thread(); 736 737 ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_UNSTARTED, 738 DIRTY_RATE_STATUS_MEASURING); 739 if (ret == -1) { 740 error_report("change dirtyrate state failed."); 741 return NULL; 742 } 743 744 calculate_dirtyrate(config); 745 746 ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_MEASURING, 747 DIRTY_RATE_STATUS_MEASURED); 748 if (ret == -1) { 749 error_report("change dirtyrate state failed."); 750 } 751 752 rcu_unregister_thread(); 753 return NULL; 754 } 755 756 void qmp_calc_dirty_rate(int64_t calc_time, 757 bool has_calc_time_unit, 758 TimeUnit calc_time_unit, 759 bool has_sample_pages, 760 int64_t sample_pages, 761 bool has_mode, 762 DirtyRateMeasureMode mode, 763 Error **errp) 764 { 765 static struct DirtyRateConfig config; 766 QemuThread thread; 767 int ret; 768 769 /* 770 * If the dirty rate is already being measured, don't attempt to start. 771 */ 772 if (qatomic_read(&CalculatingState) == DIRTY_RATE_STATUS_MEASURING) { 773 error_setg(errp, "the dirty rate is already being measured."); 774 return; 775 } 776 777 int64_t calc_time_ms = convert_time_unit( 778 calc_time, 779 has_calc_time_unit ? calc_time_unit : TIME_UNIT_SECOND, 780 TIME_UNIT_MILLISECOND 781 ); 782 783 if (!is_calc_time_valid(calc_time_ms)) { 784 error_setg(errp, "Calculation time is out of range [%dms, %dms].", 785 MIN_CALC_TIME_MS, MAX_CALC_TIME_MS); 786 return; 787 } 788 789 if (!has_mode) { 790 mode = DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING; 791 } 792 793 if (has_sample_pages && mode != DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING) { 794 error_setg(errp, "sample-pages is used only in page-sampling mode"); 795 return; 796 } 797 798 if (has_sample_pages) { 799 if (!is_sample_pages_valid(sample_pages)) { 800 error_setg(errp, "sample-pages is out of range[%d, %d].", 801 MIN_SAMPLE_PAGE_COUNT, 802 MAX_SAMPLE_PAGE_COUNT); 803 return; 804 } 805 } else { 806 sample_pages = DIRTYRATE_DEFAULT_SAMPLE_PAGES; 807 } 808 809 /* 810 * dirty ring mode only works when kvm dirty ring is enabled. 811 * on the contrary, dirty bitmap mode is not. 812 */ 813 if (((mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) && 814 !kvm_dirty_ring_enabled()) || 815 ((mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP) && 816 kvm_dirty_ring_enabled())) { 817 error_setg(errp, "mode %s is not enabled, use other method instead.", 818 DirtyRateMeasureMode_str(mode)); 819 return; 820 } 821 822 /* 823 * Init calculation state as unstarted. 824 */ 825 ret = dirtyrate_set_state(&CalculatingState, CalculatingState, 826 DIRTY_RATE_STATUS_UNSTARTED); 827 if (ret == -1) { 828 error_setg(errp, "init dirty rate calculation state failed."); 829 return; 830 } 831 832 config.calc_time_ms = calc_time_ms; 833 config.sample_pages_per_gigabytes = sample_pages; 834 config.mode = mode; 835 836 cleanup_dirtyrate_stat(config); 837 838 /* 839 * update dirty rate mode so that we can figure out what mode has 840 * been used in last calculation 841 **/ 842 dirtyrate_mode = mode; 843 844 init_dirtyrate_stat(config); 845 846 qemu_thread_create(&thread, MIGRATION_THREAD_DIRTY_RATE, 847 get_dirtyrate_thread, (void *)&config, 848 QEMU_THREAD_DETACHED); 849 } 850 851 852 struct DirtyRateInfo *qmp_query_dirty_rate(bool has_calc_time_unit, 853 TimeUnit calc_time_unit, 854 Error **errp) 855 { 856 return query_dirty_rate_info( 857 has_calc_time_unit ? calc_time_unit : TIME_UNIT_SECOND); 858 } 859 860 void hmp_info_dirty_rate(Monitor *mon, const QDict *qdict) 861 { 862 DirtyRateInfo *info = query_dirty_rate_info(TIME_UNIT_SECOND); 863 864 monitor_printf(mon, "Status: %s\n", 865 DirtyRateStatus_str(info->status)); 866 monitor_printf(mon, "Start Time: %"PRIi64" (ms)\n", 867 info->start_time); 868 if (info->mode == DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING) { 869 monitor_printf(mon, "Sample Pages: %"PRIu64" (per GB)\n", 870 info->sample_pages); 871 } 872 monitor_printf(mon, "Period: %"PRIi64" (sec)\n", 873 info->calc_time); 874 monitor_printf(mon, "Mode: %s\n", 875 DirtyRateMeasureMode_str(info->mode)); 876 monitor_printf(mon, "Dirty rate: "); 877 if (info->has_dirty_rate) { 878 monitor_printf(mon, "%"PRIi64" (MB/s)\n", info->dirty_rate); 879 if (info->has_vcpu_dirty_rate) { 880 DirtyRateVcpuList *rate, *head = info->vcpu_dirty_rate; 881 for (rate = head; rate != NULL; rate = rate->next) { 882 monitor_printf(mon, "vcpu[%"PRIi64"], Dirty rate: %"PRIi64 883 " (MB/s)\n", rate->value->id, 884 rate->value->dirty_rate); 885 } 886 } 887 } else { 888 monitor_printf(mon, "(not ready)\n"); 889 } 890 891 qapi_free_DirtyRateVcpuList(info->vcpu_dirty_rate); 892 g_free(info); 893 } 894 895 void hmp_calc_dirty_rate(Monitor *mon, const QDict *qdict) 896 { 897 int64_t sec = qdict_get_try_int(qdict, "second", 0); 898 int64_t sample_pages = qdict_get_try_int(qdict, "sample_pages_per_GB", -1); 899 bool has_sample_pages = (sample_pages != -1); 900 bool dirty_ring = qdict_get_try_bool(qdict, "dirty_ring", false); 901 bool dirty_bitmap = qdict_get_try_bool(qdict, "dirty_bitmap", false); 902 DirtyRateMeasureMode mode = DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING; 903 Error *err = NULL; 904 905 if (!sec) { 906 monitor_printf(mon, "Incorrect period length specified!\n"); 907 return; 908 } 909 910 if (dirty_ring && dirty_bitmap) { 911 monitor_printf(mon, "Either dirty ring or dirty bitmap " 912 "can be specified!\n"); 913 return; 914 } 915 916 if (dirty_bitmap) { 917 mode = DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP; 918 } else if (dirty_ring) { 919 mode = DIRTY_RATE_MEASURE_MODE_DIRTY_RING; 920 } 921 922 qmp_calc_dirty_rate(sec, /* calc-time */ 923 false, TIME_UNIT_SECOND, /* calc-time-unit */ 924 has_sample_pages, sample_pages, 925 true, mode, 926 &err); 927 if (err) { 928 hmp_handle_error(mon, err); 929 return; 930 } 931 932 monitor_printf(mon, "Starting dirty rate measurement with period %"PRIi64 933 " seconds\n", sec); 934 monitor_printf(mon, "[Please use 'info dirty_rate' to check results]\n"); 935 } 936