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 33 /* 34 * total_dirty_pages is procted by BQL and is used 35 * to stat dirty pages during the period of two 36 * memory_global_dirty_log_sync 37 */ 38 uint64_t total_dirty_pages; 39 40 typedef struct DirtyPageRecord { 41 uint64_t start_pages; 42 uint64_t end_pages; 43 } DirtyPageRecord; 44 45 static int CalculatingState = DIRTY_RATE_STATUS_UNSTARTED; 46 static struct DirtyRateStat DirtyStat; 47 static DirtyRateMeasureMode dirtyrate_mode = 48 DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING; 49 50 static int64_t dirty_stat_wait(int64_t msec, int64_t initial_time) 51 { 52 int64_t current_time; 53 54 current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 55 if ((current_time - initial_time) >= msec) { 56 msec = current_time - initial_time; 57 } else { 58 g_usleep((msec + initial_time - current_time) * 1000); 59 /* g_usleep may overshoot */ 60 msec = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) - initial_time; 61 } 62 63 return msec; 64 } 65 66 static inline void record_dirtypages(DirtyPageRecord *dirty_pages, 67 CPUState *cpu, bool start) 68 { 69 if (start) { 70 dirty_pages[cpu->cpu_index].start_pages = cpu->dirty_pages; 71 } else { 72 dirty_pages[cpu->cpu_index].end_pages = cpu->dirty_pages; 73 } 74 } 75 76 static int64_t do_calculate_dirtyrate(DirtyPageRecord dirty_pages, 77 int64_t calc_time_ms) 78 { 79 uint64_t increased_dirty_pages = 80 dirty_pages.end_pages - dirty_pages.start_pages; 81 82 /* 83 * multiply by 1000ms/s _before_ converting down to megabytes 84 * to avoid losing precision 85 */ 86 return qemu_target_pages_to_MiB(increased_dirty_pages * 1000) / 87 calc_time_ms; 88 } 89 90 void global_dirty_log_change(unsigned int flag, bool start) 91 { 92 Error *local_err = NULL; 93 bool ret; 94 95 bql_lock(); 96 if (start) { 97 ret = memory_global_dirty_log_start(flag, &local_err); 98 if (!ret) { 99 error_report_err(local_err); 100 } 101 } else { 102 memory_global_dirty_log_stop(flag); 103 } 104 bql_unlock(); 105 } 106 107 /* 108 * global_dirty_log_sync 109 * 1. sync dirty log from kvm 110 * 2. stop dirty tracking if needed. 111 */ 112 static void global_dirty_log_sync(unsigned int flag, bool one_shot) 113 { 114 bql_lock(); 115 memory_global_dirty_log_sync(false); 116 if (one_shot) { 117 memory_global_dirty_log_stop(flag); 118 } 119 bql_unlock(); 120 } 121 122 static DirtyPageRecord *vcpu_dirty_stat_alloc(VcpuStat *stat) 123 { 124 CPUState *cpu; 125 int nvcpu = 0; 126 127 CPU_FOREACH(cpu) { 128 nvcpu++; 129 } 130 131 stat->nvcpu = nvcpu; 132 stat->rates = g_new0(DirtyRateVcpu, nvcpu); 133 134 return g_new0(DirtyPageRecord, nvcpu); 135 } 136 137 static void vcpu_dirty_stat_collect(DirtyPageRecord *records, 138 bool start) 139 { 140 CPUState *cpu; 141 142 CPU_FOREACH(cpu) { 143 record_dirtypages(records, cpu, start); 144 } 145 } 146 147 int64_t vcpu_calculate_dirtyrate(int64_t calc_time_ms, 148 VcpuStat *stat, 149 unsigned int flag, 150 bool one_shot) 151 { 152 DirtyPageRecord *records; 153 int64_t init_time_ms; 154 int64_t duration; 155 int64_t dirtyrate; 156 int i = 0; 157 unsigned int gen_id; 158 159 retry: 160 init_time_ms = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 161 162 WITH_QEMU_LOCK_GUARD(&qemu_cpu_list_lock) { 163 gen_id = cpu_list_generation_id_get(); 164 records = vcpu_dirty_stat_alloc(stat); 165 vcpu_dirty_stat_collect(records, true); 166 } 167 168 duration = dirty_stat_wait(calc_time_ms, init_time_ms); 169 170 global_dirty_log_sync(flag, one_shot); 171 172 WITH_QEMU_LOCK_GUARD(&qemu_cpu_list_lock) { 173 if (gen_id != cpu_list_generation_id_get()) { 174 g_free(records); 175 g_free(stat->rates); 176 cpu_list_unlock(); 177 goto retry; 178 } 179 vcpu_dirty_stat_collect(records, false); 180 } 181 182 for (i = 0; i < stat->nvcpu; i++) { 183 dirtyrate = do_calculate_dirtyrate(records[i], duration); 184 185 stat->rates[i].id = i; 186 stat->rates[i].dirty_rate = dirtyrate; 187 188 trace_dirtyrate_do_calculate_vcpu(i, dirtyrate); 189 } 190 191 g_free(records); 192 193 return duration; 194 } 195 196 static bool is_calc_time_valid(int64_t msec) 197 { 198 if ((msec < MIN_CALC_TIME_MS) || (msec > MAX_CALC_TIME_MS)) { 199 return false; 200 } 201 202 return true; 203 } 204 205 static bool is_sample_pages_valid(int64_t pages) 206 { 207 return pages >= MIN_SAMPLE_PAGE_COUNT && 208 pages <= MAX_SAMPLE_PAGE_COUNT; 209 } 210 211 static int dirtyrate_set_state(int *state, int old_state, int new_state) 212 { 213 assert(new_state < DIRTY_RATE_STATUS__MAX); 214 trace_dirtyrate_set_state(DirtyRateStatus_str(new_state)); 215 if (qatomic_cmpxchg(state, old_state, new_state) == old_state) { 216 return 0; 217 } else { 218 return -1; 219 } 220 } 221 222 /* Decimal power of given time unit relative to one second */ 223 static int time_unit_to_power(TimeUnit time_unit) 224 { 225 switch (time_unit) { 226 case TIME_UNIT_SECOND: 227 return 0; 228 case TIME_UNIT_MILLISECOND: 229 return -3; 230 default: 231 assert(false); /* unreachable */ 232 return 0; 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; 440 441 /* Right shift 30 bits to calc ramblock size in GB */ 442 info->sample_pages_count = (qemu_ram_get_used_length(block) * 443 sample_pages_per_gigabytes) >> 30; 444 /* Right shift TARGET_PAGE_BITS to calc page count */ 445 info->ramblock_pages = qemu_ram_get_used_length(block) >> 446 qemu_target_page_bits(); 447 info->ramblock_addr = qemu_ram_get_host_addr(block); 448 strcpy(info->idstr, qemu_ram_get_idstr(block)); 449 } 450 451 static void free_ramblock_dirty_info(struct RamblockDirtyInfo *infos, int count) 452 { 453 int i; 454 455 if (!infos) { 456 return; 457 } 458 459 for (i = 0; i < count; i++) { 460 g_free(infos[i].sample_page_vfn); 461 g_free(infos[i].hash_result); 462 } 463 g_free(infos); 464 } 465 466 static bool skip_sample_ramblock(RAMBlock *block) 467 { 468 /* 469 * Sample only blocks larger than MIN_RAMBLOCK_SIZE. 470 */ 471 if (qemu_ram_get_used_length(block) < (MIN_RAMBLOCK_SIZE << 10)) { 472 trace_skip_sample_ramblock(block->idstr, 473 qemu_ram_get_used_length(block)); 474 return true; 475 } 476 477 return false; 478 } 479 480 static bool record_ramblock_hash_info(struct RamblockDirtyInfo **block_dinfo, 481 struct DirtyRateConfig config, 482 int *block_count) 483 { 484 struct RamblockDirtyInfo *info = NULL; 485 struct RamblockDirtyInfo *dinfo = NULL; 486 RAMBlock *block = NULL; 487 int total_count = 0; 488 int index = 0; 489 bool ret = false; 490 491 RAMBLOCK_FOREACH_MIGRATABLE(block) { 492 if (skip_sample_ramblock(block)) { 493 continue; 494 } 495 total_count++; 496 } 497 498 dinfo = g_try_malloc0_n(total_count, sizeof(struct RamblockDirtyInfo)); 499 if (dinfo == NULL) { 500 goto out; 501 } 502 503 RAMBLOCK_FOREACH_MIGRATABLE(block) { 504 if (skip_sample_ramblock(block)) { 505 continue; 506 } 507 if (index >= total_count) { 508 break; 509 } 510 info = &dinfo[index]; 511 get_ramblock_dirty_info(block, info, &config); 512 if (!save_ramblock_hash(info)) { 513 goto out; 514 } 515 index++; 516 } 517 ret = true; 518 519 out: 520 *block_count = index; 521 *block_dinfo = dinfo; 522 return ret; 523 } 524 525 static void calc_page_dirty_rate(struct RamblockDirtyInfo *info) 526 { 527 uint32_t hash; 528 int i; 529 530 for (i = 0; i < info->sample_pages_count; i++) { 531 hash = get_ramblock_vfn_hash(info, info->sample_page_vfn[i]); 532 if (hash != info->hash_result[i]) { 533 trace_calc_page_dirty_rate(info->idstr, hash, info->hash_result[i]); 534 info->sample_dirty_count++; 535 } 536 } 537 } 538 539 static struct RamblockDirtyInfo * 540 find_block_matched(RAMBlock *block, int count, 541 struct RamblockDirtyInfo *infos) 542 { 543 int i; 544 545 for (i = 0; i < count; i++) { 546 if (!strcmp(infos[i].idstr, qemu_ram_get_idstr(block))) { 547 break; 548 } 549 } 550 551 if (i == count) { 552 return NULL; 553 } 554 555 if (infos[i].ramblock_addr != qemu_ram_get_host_addr(block) || 556 infos[i].ramblock_pages != 557 (qemu_ram_get_used_length(block) >> qemu_target_page_bits())) { 558 trace_find_page_matched(block->idstr); 559 return NULL; 560 } 561 562 return &infos[i]; 563 } 564 565 static bool compare_page_hash_info(struct RamblockDirtyInfo *info, 566 int block_count) 567 { 568 struct RamblockDirtyInfo *block_dinfo = NULL; 569 RAMBlock *block = NULL; 570 571 RAMBLOCK_FOREACH_MIGRATABLE(block) { 572 if (skip_sample_ramblock(block)) { 573 continue; 574 } 575 block_dinfo = find_block_matched(block, block_count, info); 576 if (block_dinfo == NULL) { 577 continue; 578 } 579 calc_page_dirty_rate(block_dinfo); 580 update_dirtyrate_stat(block_dinfo); 581 } 582 583 if (DirtyStat.page_sampling.total_sample_count == 0) { 584 return false; 585 } 586 587 return true; 588 } 589 590 static inline void record_dirtypages_bitmap(DirtyPageRecord *dirty_pages, 591 bool start) 592 { 593 if (start) { 594 dirty_pages->start_pages = total_dirty_pages; 595 } else { 596 dirty_pages->end_pages = total_dirty_pages; 597 } 598 } 599 600 static inline void dirtyrate_manual_reset_protect(void) 601 { 602 RAMBlock *block = NULL; 603 604 WITH_RCU_READ_LOCK_GUARD() { 605 RAMBLOCK_FOREACH_MIGRATABLE(block) { 606 memory_region_clear_dirty_bitmap(block->mr, 0, 607 block->used_length); 608 } 609 } 610 } 611 612 static void calculate_dirtyrate_dirty_bitmap(struct DirtyRateConfig config) 613 { 614 int64_t start_time; 615 DirtyPageRecord dirty_pages; 616 Error *local_err = NULL; 617 618 bql_lock(); 619 if (!memory_global_dirty_log_start(GLOBAL_DIRTY_DIRTY_RATE, &local_err)) { 620 error_report_err(local_err); 621 } 622 623 /* 624 * 1'round of log sync may return all 1 bits with 625 * KVM_DIRTY_LOG_INITIALLY_SET enable 626 * skip it unconditionally and start dirty tracking 627 * from 2'round of log sync 628 */ 629 memory_global_dirty_log_sync(false); 630 631 /* 632 * reset page protect manually and unconditionally. 633 * this make sure kvm dirty log be cleared if 634 * KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE cap is enabled. 635 */ 636 dirtyrate_manual_reset_protect(); 637 bql_unlock(); 638 639 record_dirtypages_bitmap(&dirty_pages, true); 640 641 start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 642 DirtyStat.start_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) / 1000; 643 644 DirtyStat.calc_time_ms = dirty_stat_wait(config.calc_time_ms, start_time); 645 646 /* 647 * do two things. 648 * 1. fetch dirty bitmap from kvm 649 * 2. stop dirty tracking 650 */ 651 global_dirty_log_sync(GLOBAL_DIRTY_DIRTY_RATE, true); 652 653 record_dirtypages_bitmap(&dirty_pages, false); 654 655 DirtyStat.dirty_rate = do_calculate_dirtyrate(dirty_pages, 656 DirtyStat.calc_time_ms); 657 } 658 659 static void calculate_dirtyrate_dirty_ring(struct DirtyRateConfig config) 660 { 661 uint64_t dirtyrate = 0; 662 uint64_t dirtyrate_sum = 0; 663 int i = 0; 664 665 /* start log sync */ 666 global_dirty_log_change(GLOBAL_DIRTY_DIRTY_RATE, true); 667 668 DirtyStat.start_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) / 1000; 669 670 /* calculate vcpu dirtyrate */ 671 DirtyStat.calc_time_ms = vcpu_calculate_dirtyrate(config.calc_time_ms, 672 &DirtyStat.dirty_ring, 673 GLOBAL_DIRTY_DIRTY_RATE, 674 true); 675 676 /* calculate vm dirtyrate */ 677 for (i = 0; i < DirtyStat.dirty_ring.nvcpu; i++) { 678 dirtyrate = DirtyStat.dirty_ring.rates[i].dirty_rate; 679 DirtyStat.dirty_ring.rates[i].dirty_rate = dirtyrate; 680 dirtyrate_sum += dirtyrate; 681 } 682 683 DirtyStat.dirty_rate = dirtyrate_sum; 684 } 685 686 static void calculate_dirtyrate_sample_vm(struct DirtyRateConfig config) 687 { 688 struct RamblockDirtyInfo *block_dinfo = NULL; 689 int block_count = 0; 690 int64_t initial_time; 691 692 rcu_read_lock(); 693 initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); 694 DirtyStat.start_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) / 1000; 695 if (!record_ramblock_hash_info(&block_dinfo, config, &block_count)) { 696 goto out; 697 } 698 rcu_read_unlock(); 699 700 DirtyStat.calc_time_ms = dirty_stat_wait(config.calc_time_ms, 701 initial_time); 702 703 rcu_read_lock(); 704 if (!compare_page_hash_info(block_dinfo, block_count)) { 705 goto out; 706 } 707 708 update_dirtyrate(DirtyStat.calc_time_ms); 709 710 out: 711 rcu_read_unlock(); 712 free_ramblock_dirty_info(block_dinfo, block_count); 713 } 714 715 static void calculate_dirtyrate(struct DirtyRateConfig config) 716 { 717 if (config.mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP) { 718 calculate_dirtyrate_dirty_bitmap(config); 719 } else if (config.mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) { 720 calculate_dirtyrate_dirty_ring(config); 721 } else { 722 calculate_dirtyrate_sample_vm(config); 723 } 724 725 trace_dirtyrate_calculate(DirtyStat.dirty_rate); 726 } 727 728 void *get_dirtyrate_thread(void *arg) 729 { 730 struct DirtyRateConfig config = *(struct DirtyRateConfig *)arg; 731 int ret; 732 rcu_register_thread(); 733 734 ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_UNSTARTED, 735 DIRTY_RATE_STATUS_MEASURING); 736 if (ret == -1) { 737 error_report("change dirtyrate state failed."); 738 return NULL; 739 } 740 741 calculate_dirtyrate(config); 742 743 ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_MEASURING, 744 DIRTY_RATE_STATUS_MEASURED); 745 if (ret == -1) { 746 error_report("change dirtyrate state failed."); 747 } 748 749 rcu_unregister_thread(); 750 return NULL; 751 } 752 753 void qmp_calc_dirty_rate(int64_t calc_time, 754 bool has_calc_time_unit, 755 TimeUnit calc_time_unit, 756 bool has_sample_pages, 757 int64_t sample_pages, 758 bool has_mode, 759 DirtyRateMeasureMode mode, 760 Error **errp) 761 { 762 static struct DirtyRateConfig config; 763 QemuThread thread; 764 int ret; 765 766 /* 767 * If the dirty rate is already being measured, don't attempt to start. 768 */ 769 if (qatomic_read(&CalculatingState) == DIRTY_RATE_STATUS_MEASURING) { 770 error_setg(errp, "the dirty rate is already being measured."); 771 return; 772 } 773 774 int64_t calc_time_ms = convert_time_unit( 775 calc_time, 776 has_calc_time_unit ? calc_time_unit : TIME_UNIT_SECOND, 777 TIME_UNIT_MILLISECOND 778 ); 779 780 if (!is_calc_time_valid(calc_time_ms)) { 781 error_setg(errp, "Calculation time is out of range [%dms, %dms].", 782 MIN_CALC_TIME_MS, MAX_CALC_TIME_MS); 783 return; 784 } 785 786 if (!has_mode) { 787 mode = DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING; 788 } 789 790 if (has_sample_pages && mode != DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING) { 791 error_setg(errp, "sample-pages is used only in page-sampling mode"); 792 return; 793 } 794 795 if (has_sample_pages) { 796 if (!is_sample_pages_valid(sample_pages)) { 797 error_setg(errp, "sample-pages is out of range[%d, %d].", 798 MIN_SAMPLE_PAGE_COUNT, 799 MAX_SAMPLE_PAGE_COUNT); 800 return; 801 } 802 } else { 803 sample_pages = DIRTYRATE_DEFAULT_SAMPLE_PAGES; 804 } 805 806 /* 807 * dirty ring mode only works when kvm dirty ring is enabled. 808 * on the contrary, dirty bitmap mode is not. 809 */ 810 if (((mode == DIRTY_RATE_MEASURE_MODE_DIRTY_RING) && 811 !kvm_dirty_ring_enabled()) || 812 ((mode == DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP) && 813 kvm_dirty_ring_enabled())) { 814 error_setg(errp, "mode %s is not enabled, use other method instead.", 815 DirtyRateMeasureMode_str(mode)); 816 return; 817 } 818 819 /* 820 * Init calculation state as unstarted. 821 */ 822 ret = dirtyrate_set_state(&CalculatingState, CalculatingState, 823 DIRTY_RATE_STATUS_UNSTARTED); 824 if (ret == -1) { 825 error_setg(errp, "init dirty rate calculation state failed."); 826 return; 827 } 828 829 config.calc_time_ms = calc_time_ms; 830 config.sample_pages_per_gigabytes = sample_pages; 831 config.mode = mode; 832 833 cleanup_dirtyrate_stat(config); 834 835 /* 836 * update dirty rate mode so that we can figure out what mode has 837 * been used in last calculation 838 **/ 839 dirtyrate_mode = mode; 840 841 init_dirtyrate_stat(config); 842 843 qemu_thread_create(&thread, "get_dirtyrate", get_dirtyrate_thread, 844 (void *)&config, QEMU_THREAD_DETACHED); 845 } 846 847 848 struct DirtyRateInfo *qmp_query_dirty_rate(bool has_calc_time_unit, 849 TimeUnit calc_time_unit, 850 Error **errp) 851 { 852 return query_dirty_rate_info( 853 has_calc_time_unit ? calc_time_unit : TIME_UNIT_SECOND); 854 } 855 856 void hmp_info_dirty_rate(Monitor *mon, const QDict *qdict) 857 { 858 DirtyRateInfo *info = query_dirty_rate_info(TIME_UNIT_SECOND); 859 860 monitor_printf(mon, "Status: %s\n", 861 DirtyRateStatus_str(info->status)); 862 monitor_printf(mon, "Start Time: %"PRIi64" (ms)\n", 863 info->start_time); 864 if (info->mode == DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING) { 865 monitor_printf(mon, "Sample Pages: %"PRIu64" (per GB)\n", 866 info->sample_pages); 867 } 868 monitor_printf(mon, "Period: %"PRIi64" (sec)\n", 869 info->calc_time); 870 monitor_printf(mon, "Mode: %s\n", 871 DirtyRateMeasureMode_str(info->mode)); 872 monitor_printf(mon, "Dirty rate: "); 873 if (info->has_dirty_rate) { 874 monitor_printf(mon, "%"PRIi64" (MB/s)\n", info->dirty_rate); 875 if (info->has_vcpu_dirty_rate) { 876 DirtyRateVcpuList *rate, *head = info->vcpu_dirty_rate; 877 for (rate = head; rate != NULL; rate = rate->next) { 878 monitor_printf(mon, "vcpu[%"PRIi64"], Dirty rate: %"PRIi64 879 " (MB/s)\n", rate->value->id, 880 rate->value->dirty_rate); 881 } 882 } 883 } else { 884 monitor_printf(mon, "(not ready)\n"); 885 } 886 887 qapi_free_DirtyRateVcpuList(info->vcpu_dirty_rate); 888 g_free(info); 889 } 890 891 void hmp_calc_dirty_rate(Monitor *mon, const QDict *qdict) 892 { 893 int64_t sec = qdict_get_try_int(qdict, "second", 0); 894 int64_t sample_pages = qdict_get_try_int(qdict, "sample_pages_per_GB", -1); 895 bool has_sample_pages = (sample_pages != -1); 896 bool dirty_ring = qdict_get_try_bool(qdict, "dirty_ring", false); 897 bool dirty_bitmap = qdict_get_try_bool(qdict, "dirty_bitmap", false); 898 DirtyRateMeasureMode mode = DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING; 899 Error *err = NULL; 900 901 if (!sec) { 902 monitor_printf(mon, "Incorrect period length specified!\n"); 903 return; 904 } 905 906 if (dirty_ring && dirty_bitmap) { 907 monitor_printf(mon, "Either dirty ring or dirty bitmap " 908 "can be specified!\n"); 909 return; 910 } 911 912 if (dirty_bitmap) { 913 mode = DIRTY_RATE_MEASURE_MODE_DIRTY_BITMAP; 914 } else if (dirty_ring) { 915 mode = DIRTY_RATE_MEASURE_MODE_DIRTY_RING; 916 } 917 918 qmp_calc_dirty_rate(sec, /* calc-time */ 919 false, TIME_UNIT_SECOND, /* calc-time-unit */ 920 has_sample_pages, sample_pages, 921 true, mode, 922 &err); 923 if (err) { 924 hmp_handle_error(mon, err); 925 return; 926 } 927 928 monitor_printf(mon, "Starting dirty rate measurement with period %"PRIi64 929 " seconds\n", sec); 930 monitor_printf(mon, "[Please use 'info dirty_rate' to check results]\n"); 931 } 932