1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * KVM dirty page logging test 4 * 5 * Copyright (C) 2018, Red Hat, Inc. 6 */ 7 8 #define _GNU_SOURCE /* for program_invocation_name */ 9 10 #include <stdio.h> 11 #include <stdlib.h> 12 #include <pthread.h> 13 #include <semaphore.h> 14 #include <sys/types.h> 15 #include <signal.h> 16 #include <errno.h> 17 #include <linux/bitmap.h> 18 #include <linux/bitops.h> 19 #include <linux/atomic.h> 20 21 #include "kvm_util.h" 22 #include "test_util.h" 23 #include "guest_modes.h" 24 #include "processor.h" 25 26 #define VCPU_ID 1 27 28 /* The memory slot index to track dirty pages */ 29 #define TEST_MEM_SLOT_INDEX 1 30 31 /* Default guest test virtual memory offset */ 32 #define DEFAULT_GUEST_TEST_MEM 0xc0000000 33 34 /* How many pages to dirty for each guest loop */ 35 #define TEST_PAGES_PER_LOOP 1024 36 37 /* How many host loops to run (one KVM_GET_DIRTY_LOG for each loop) */ 38 #define TEST_HOST_LOOP_N 32UL 39 40 /* Interval for each host loop (ms) */ 41 #define TEST_HOST_LOOP_INTERVAL 10UL 42 43 /* Dirty bitmaps are always little endian, so we need to swap on big endian */ 44 #if defined(__s390x__) 45 # define BITOP_LE_SWIZZLE ((BITS_PER_LONG-1) & ~0x7) 46 # define test_bit_le(nr, addr) \ 47 test_bit((nr) ^ BITOP_LE_SWIZZLE, addr) 48 # define set_bit_le(nr, addr) \ 49 set_bit((nr) ^ BITOP_LE_SWIZZLE, addr) 50 # define clear_bit_le(nr, addr) \ 51 clear_bit((nr) ^ BITOP_LE_SWIZZLE, addr) 52 # define test_and_set_bit_le(nr, addr) \ 53 test_and_set_bit((nr) ^ BITOP_LE_SWIZZLE, addr) 54 # define test_and_clear_bit_le(nr, addr) \ 55 test_and_clear_bit((nr) ^ BITOP_LE_SWIZZLE, addr) 56 #else 57 # define test_bit_le test_bit 58 # define set_bit_le set_bit 59 # define clear_bit_le clear_bit 60 # define test_and_set_bit_le test_and_set_bit 61 # define test_and_clear_bit_le test_and_clear_bit 62 #endif 63 64 #define TEST_DIRTY_RING_COUNT 65536 65 66 #define SIG_IPI SIGUSR1 67 68 /* 69 * Guest/Host shared variables. Ensure addr_gva2hva() and/or 70 * sync_global_to/from_guest() are used when accessing from 71 * the host. READ/WRITE_ONCE() should also be used with anything 72 * that may change. 73 */ 74 static uint64_t host_page_size; 75 static uint64_t guest_page_size; 76 static uint64_t guest_num_pages; 77 static uint64_t random_array[TEST_PAGES_PER_LOOP]; 78 static uint64_t iteration; 79 80 /* 81 * Guest physical memory offset of the testing memory slot. 82 * This will be set to the topmost valid physical address minus 83 * the test memory size. 84 */ 85 static uint64_t guest_test_phys_mem; 86 87 /* 88 * Guest virtual memory offset of the testing memory slot. 89 * Must not conflict with identity mapped test code. 90 */ 91 static uint64_t guest_test_virt_mem = DEFAULT_GUEST_TEST_MEM; 92 93 /* 94 * Continuously write to the first 8 bytes of a random pages within 95 * the testing memory region. 96 */ 97 static void guest_code(void) 98 { 99 uint64_t addr; 100 int i; 101 102 /* 103 * On s390x, all pages of a 1M segment are initially marked as dirty 104 * when a page of the segment is written to for the very first time. 105 * To compensate this specialty in this test, we need to touch all 106 * pages during the first iteration. 107 */ 108 for (i = 0; i < guest_num_pages; i++) { 109 addr = guest_test_virt_mem + i * guest_page_size; 110 *(uint64_t *)addr = READ_ONCE(iteration); 111 } 112 113 while (true) { 114 for (i = 0; i < TEST_PAGES_PER_LOOP; i++) { 115 addr = guest_test_virt_mem; 116 addr += (READ_ONCE(random_array[i]) % guest_num_pages) 117 * guest_page_size; 118 addr = align_down(addr, host_page_size); 119 *(uint64_t *)addr = READ_ONCE(iteration); 120 } 121 122 /* Tell the host that we need more random numbers */ 123 GUEST_SYNC(1); 124 } 125 } 126 127 /* Host variables */ 128 static bool host_quit; 129 130 /* Points to the test VM memory region on which we track dirty logs */ 131 static void *host_test_mem; 132 static uint64_t host_num_pages; 133 134 /* For statistics only */ 135 static uint64_t host_dirty_count; 136 static uint64_t host_clear_count; 137 static uint64_t host_track_next_count; 138 139 /* Whether dirty ring reset is requested, or finished */ 140 static sem_t sem_vcpu_stop; 141 static sem_t sem_vcpu_cont; 142 /* 143 * This is only set by main thread, and only cleared by vcpu thread. It is 144 * used to request vcpu thread to stop at the next GUEST_SYNC, since GUEST_SYNC 145 * is the only place that we'll guarantee both "dirty bit" and "dirty data" 146 * will match. E.g., SIG_IPI won't guarantee that if the vcpu is interrupted 147 * after setting dirty bit but before the data is written. 148 */ 149 static atomic_t vcpu_sync_stop_requested; 150 /* 151 * This is updated by the vcpu thread to tell the host whether it's a 152 * ring-full event. It should only be read until a sem_wait() of 153 * sem_vcpu_stop and before vcpu continues to run. 154 */ 155 static bool dirty_ring_vcpu_ring_full; 156 /* 157 * This is only used for verifying the dirty pages. Dirty ring has a very 158 * tricky case when the ring just got full, kvm will do userspace exit due to 159 * ring full. When that happens, the very last PFN is set but actually the 160 * data is not changed (the guest WRITE is not really applied yet), because 161 * we found that the dirty ring is full, refused to continue the vcpu, and 162 * recorded the dirty gfn with the old contents. 163 * 164 * For this specific case, it's safe to skip checking this pfn for this 165 * bit, because it's a redundant bit, and when the write happens later the bit 166 * will be set again. We use this variable to always keep track of the latest 167 * dirty gfn we've collected, so that if a mismatch of data found later in the 168 * verifying process, we let it pass. 169 */ 170 static uint64_t dirty_ring_last_page; 171 172 enum log_mode_t { 173 /* Only use KVM_GET_DIRTY_LOG for logging */ 174 LOG_MODE_DIRTY_LOG = 0, 175 176 /* Use both KVM_[GET|CLEAR]_DIRTY_LOG for logging */ 177 LOG_MODE_CLEAR_LOG = 1, 178 179 /* Use dirty ring for logging */ 180 LOG_MODE_DIRTY_RING = 2, 181 182 LOG_MODE_NUM, 183 184 /* Run all supported modes */ 185 LOG_MODE_ALL = LOG_MODE_NUM, 186 }; 187 188 /* Mode of logging to test. Default is to run all supported modes */ 189 static enum log_mode_t host_log_mode_option = LOG_MODE_ALL; 190 /* Logging mode for current run */ 191 static enum log_mode_t host_log_mode; 192 static pthread_t vcpu_thread; 193 static uint32_t test_dirty_ring_count = TEST_DIRTY_RING_COUNT; 194 195 static void vcpu_kick(void) 196 { 197 pthread_kill(vcpu_thread, SIG_IPI); 198 } 199 200 /* 201 * In our test we do signal tricks, let's use a better version of 202 * sem_wait to avoid signal interrupts 203 */ 204 static void sem_wait_until(sem_t *sem) 205 { 206 int ret; 207 208 do 209 ret = sem_wait(sem); 210 while (ret == -1 && errno == EINTR); 211 } 212 213 static bool clear_log_supported(void) 214 { 215 return kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2); 216 } 217 218 static void clear_log_create_vm_done(struct kvm_vm *vm) 219 { 220 struct kvm_enable_cap cap = {}; 221 u64 manual_caps; 222 223 manual_caps = kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2); 224 TEST_ASSERT(manual_caps, "MANUAL_CAPS is zero!"); 225 manual_caps &= (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE | 226 KVM_DIRTY_LOG_INITIALLY_SET); 227 cap.cap = KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2; 228 cap.args[0] = manual_caps; 229 vm_enable_cap(vm, &cap); 230 } 231 232 static void dirty_log_collect_dirty_pages(struct kvm_vm *vm, int slot, 233 void *bitmap, uint32_t num_pages) 234 { 235 kvm_vm_get_dirty_log(vm, slot, bitmap); 236 } 237 238 static void clear_log_collect_dirty_pages(struct kvm_vm *vm, int slot, 239 void *bitmap, uint32_t num_pages) 240 { 241 kvm_vm_get_dirty_log(vm, slot, bitmap); 242 kvm_vm_clear_dirty_log(vm, slot, bitmap, 0, num_pages); 243 } 244 245 /* Should only be called after a GUEST_SYNC */ 246 static void vcpu_handle_sync_stop(void) 247 { 248 if (atomic_read(&vcpu_sync_stop_requested)) { 249 /* It means main thread is sleeping waiting */ 250 atomic_set(&vcpu_sync_stop_requested, false); 251 sem_post(&sem_vcpu_stop); 252 sem_wait_until(&sem_vcpu_cont); 253 } 254 } 255 256 static void default_after_vcpu_run(struct kvm_vm *vm, int ret, int err) 257 { 258 struct kvm_run *run = vcpu_state(vm, VCPU_ID); 259 260 TEST_ASSERT(ret == 0 || (ret == -1 && err == EINTR), 261 "vcpu run failed: errno=%d", err); 262 263 TEST_ASSERT(get_ucall(vm, VCPU_ID, NULL) == UCALL_SYNC, 264 "Invalid guest sync status: exit_reason=%s\n", 265 exit_reason_str(run->exit_reason)); 266 267 vcpu_handle_sync_stop(); 268 } 269 270 static bool dirty_ring_supported(void) 271 { 272 return kvm_check_cap(KVM_CAP_DIRTY_LOG_RING); 273 } 274 275 static void dirty_ring_create_vm_done(struct kvm_vm *vm) 276 { 277 /* 278 * Switch to dirty ring mode after VM creation but before any 279 * of the vcpu creation. 280 */ 281 vm_enable_dirty_ring(vm, test_dirty_ring_count * 282 sizeof(struct kvm_dirty_gfn)); 283 } 284 285 static inline bool dirty_gfn_is_dirtied(struct kvm_dirty_gfn *gfn) 286 { 287 return gfn->flags == KVM_DIRTY_GFN_F_DIRTY; 288 } 289 290 static inline void dirty_gfn_set_collected(struct kvm_dirty_gfn *gfn) 291 { 292 gfn->flags = KVM_DIRTY_GFN_F_RESET; 293 } 294 295 static uint32_t dirty_ring_collect_one(struct kvm_dirty_gfn *dirty_gfns, 296 int slot, void *bitmap, 297 uint32_t num_pages, uint32_t *fetch_index) 298 { 299 struct kvm_dirty_gfn *cur; 300 uint32_t count = 0; 301 302 while (true) { 303 cur = &dirty_gfns[*fetch_index % test_dirty_ring_count]; 304 if (!dirty_gfn_is_dirtied(cur)) 305 break; 306 TEST_ASSERT(cur->slot == slot, "Slot number didn't match: " 307 "%u != %u", cur->slot, slot); 308 TEST_ASSERT(cur->offset < num_pages, "Offset overflow: " 309 "0x%llx >= 0x%x", cur->offset, num_pages); 310 //pr_info("fetch 0x%x page %llu\n", *fetch_index, cur->offset); 311 set_bit_le(cur->offset, bitmap); 312 dirty_ring_last_page = cur->offset; 313 dirty_gfn_set_collected(cur); 314 (*fetch_index)++; 315 count++; 316 } 317 318 return count; 319 } 320 321 static void dirty_ring_wait_vcpu(void) 322 { 323 /* This makes sure that hardware PML cache flushed */ 324 vcpu_kick(); 325 sem_wait_until(&sem_vcpu_stop); 326 } 327 328 static void dirty_ring_continue_vcpu(void) 329 { 330 pr_info("Notifying vcpu to continue\n"); 331 sem_post(&sem_vcpu_cont); 332 } 333 334 static void dirty_ring_collect_dirty_pages(struct kvm_vm *vm, int slot, 335 void *bitmap, uint32_t num_pages) 336 { 337 /* We only have one vcpu */ 338 static uint32_t fetch_index = 0; 339 uint32_t count = 0, cleared; 340 bool continued_vcpu = false; 341 342 dirty_ring_wait_vcpu(); 343 344 if (!dirty_ring_vcpu_ring_full) { 345 /* 346 * This is not a ring-full event, it's safe to allow 347 * vcpu to continue 348 */ 349 dirty_ring_continue_vcpu(); 350 continued_vcpu = true; 351 } 352 353 /* Only have one vcpu */ 354 count = dirty_ring_collect_one(vcpu_map_dirty_ring(vm, VCPU_ID), 355 slot, bitmap, num_pages, &fetch_index); 356 357 cleared = kvm_vm_reset_dirty_ring(vm); 358 359 /* Cleared pages should be the same as collected */ 360 TEST_ASSERT(cleared == count, "Reset dirty pages (%u) mismatch " 361 "with collected (%u)", cleared, count); 362 363 if (!continued_vcpu) { 364 TEST_ASSERT(dirty_ring_vcpu_ring_full, 365 "Didn't continue vcpu even without ring full"); 366 dirty_ring_continue_vcpu(); 367 } 368 369 pr_info("Iteration %ld collected %u pages\n", iteration, count); 370 } 371 372 static void dirty_ring_after_vcpu_run(struct kvm_vm *vm, int ret, int err) 373 { 374 struct kvm_run *run = vcpu_state(vm, VCPU_ID); 375 376 /* A ucall-sync or ring-full event is allowed */ 377 if (get_ucall(vm, VCPU_ID, NULL) == UCALL_SYNC) { 378 /* We should allow this to continue */ 379 ; 380 } else if (run->exit_reason == KVM_EXIT_DIRTY_RING_FULL || 381 (ret == -1 && err == EINTR)) { 382 /* Update the flag first before pause */ 383 WRITE_ONCE(dirty_ring_vcpu_ring_full, 384 run->exit_reason == KVM_EXIT_DIRTY_RING_FULL); 385 sem_post(&sem_vcpu_stop); 386 pr_info("vcpu stops because %s...\n", 387 dirty_ring_vcpu_ring_full ? 388 "dirty ring is full" : "vcpu is kicked out"); 389 sem_wait_until(&sem_vcpu_cont); 390 pr_info("vcpu continues now.\n"); 391 } else { 392 TEST_ASSERT(false, "Invalid guest sync status: " 393 "exit_reason=%s\n", 394 exit_reason_str(run->exit_reason)); 395 } 396 } 397 398 static void dirty_ring_before_vcpu_join(void) 399 { 400 /* Kick another round of vcpu just to make sure it will quit */ 401 sem_post(&sem_vcpu_cont); 402 } 403 404 struct log_mode { 405 const char *name; 406 /* Return true if this mode is supported, otherwise false */ 407 bool (*supported)(void); 408 /* Hook when the vm creation is done (before vcpu creation) */ 409 void (*create_vm_done)(struct kvm_vm *vm); 410 /* Hook to collect the dirty pages into the bitmap provided */ 411 void (*collect_dirty_pages) (struct kvm_vm *vm, int slot, 412 void *bitmap, uint32_t num_pages); 413 /* Hook to call when after each vcpu run */ 414 void (*after_vcpu_run)(struct kvm_vm *vm, int ret, int err); 415 void (*before_vcpu_join) (void); 416 } log_modes[LOG_MODE_NUM] = { 417 { 418 .name = "dirty-log", 419 .collect_dirty_pages = dirty_log_collect_dirty_pages, 420 .after_vcpu_run = default_after_vcpu_run, 421 }, 422 { 423 .name = "clear-log", 424 .supported = clear_log_supported, 425 .create_vm_done = clear_log_create_vm_done, 426 .collect_dirty_pages = clear_log_collect_dirty_pages, 427 .after_vcpu_run = default_after_vcpu_run, 428 }, 429 { 430 .name = "dirty-ring", 431 .supported = dirty_ring_supported, 432 .create_vm_done = dirty_ring_create_vm_done, 433 .collect_dirty_pages = dirty_ring_collect_dirty_pages, 434 .before_vcpu_join = dirty_ring_before_vcpu_join, 435 .after_vcpu_run = dirty_ring_after_vcpu_run, 436 }, 437 }; 438 439 /* 440 * We use this bitmap to track some pages that should have its dirty 441 * bit set in the _next_ iteration. For example, if we detected the 442 * page value changed to current iteration but at the same time the 443 * page bit is cleared in the latest bitmap, then the system must 444 * report that write in the next get dirty log call. 445 */ 446 static unsigned long *host_bmap_track; 447 448 static void log_modes_dump(void) 449 { 450 int i; 451 452 printf("all"); 453 for (i = 0; i < LOG_MODE_NUM; i++) 454 printf(", %s", log_modes[i].name); 455 printf("\n"); 456 } 457 458 static bool log_mode_supported(void) 459 { 460 struct log_mode *mode = &log_modes[host_log_mode]; 461 462 if (mode->supported) 463 return mode->supported(); 464 465 return true; 466 } 467 468 static void log_mode_create_vm_done(struct kvm_vm *vm) 469 { 470 struct log_mode *mode = &log_modes[host_log_mode]; 471 472 if (mode->create_vm_done) 473 mode->create_vm_done(vm); 474 } 475 476 static void log_mode_collect_dirty_pages(struct kvm_vm *vm, int slot, 477 void *bitmap, uint32_t num_pages) 478 { 479 struct log_mode *mode = &log_modes[host_log_mode]; 480 481 TEST_ASSERT(mode->collect_dirty_pages != NULL, 482 "collect_dirty_pages() is required for any log mode!"); 483 mode->collect_dirty_pages(vm, slot, bitmap, num_pages); 484 } 485 486 static void log_mode_after_vcpu_run(struct kvm_vm *vm, int ret, int err) 487 { 488 struct log_mode *mode = &log_modes[host_log_mode]; 489 490 if (mode->after_vcpu_run) 491 mode->after_vcpu_run(vm, ret, err); 492 } 493 494 static void log_mode_before_vcpu_join(void) 495 { 496 struct log_mode *mode = &log_modes[host_log_mode]; 497 498 if (mode->before_vcpu_join) 499 mode->before_vcpu_join(); 500 } 501 502 static void generate_random_array(uint64_t *guest_array, uint64_t size) 503 { 504 uint64_t i; 505 506 for (i = 0; i < size; i++) 507 guest_array[i] = random(); 508 } 509 510 static void *vcpu_worker(void *data) 511 { 512 int ret, vcpu_fd; 513 struct kvm_vm *vm = data; 514 uint64_t *guest_array; 515 uint64_t pages_count = 0; 516 struct kvm_signal_mask *sigmask = alloca(offsetof(struct kvm_signal_mask, sigset) 517 + sizeof(sigset_t)); 518 sigset_t *sigset = (sigset_t *) &sigmask->sigset; 519 520 vcpu_fd = vcpu_get_fd(vm, VCPU_ID); 521 522 /* 523 * SIG_IPI is unblocked atomically while in KVM_RUN. It causes the 524 * ioctl to return with -EINTR, but it is still pending and we need 525 * to accept it with the sigwait. 526 */ 527 sigmask->len = 8; 528 pthread_sigmask(0, NULL, sigset); 529 sigdelset(sigset, SIG_IPI); 530 vcpu_ioctl(vm, VCPU_ID, KVM_SET_SIGNAL_MASK, sigmask); 531 532 sigemptyset(sigset); 533 sigaddset(sigset, SIG_IPI); 534 535 guest_array = addr_gva2hva(vm, (vm_vaddr_t)random_array); 536 537 while (!READ_ONCE(host_quit)) { 538 /* Clear any existing kick signals */ 539 generate_random_array(guest_array, TEST_PAGES_PER_LOOP); 540 pages_count += TEST_PAGES_PER_LOOP; 541 /* Let the guest dirty the random pages */ 542 ret = ioctl(vcpu_fd, KVM_RUN, NULL); 543 if (ret == -1 && errno == EINTR) { 544 int sig = -1; 545 sigwait(sigset, &sig); 546 assert(sig == SIG_IPI); 547 } 548 log_mode_after_vcpu_run(vm, ret, errno); 549 } 550 551 pr_info("Dirtied %"PRIu64" pages\n", pages_count); 552 553 return NULL; 554 } 555 556 static void vm_dirty_log_verify(enum vm_guest_mode mode, unsigned long *bmap) 557 { 558 uint64_t step = vm_num_host_pages(mode, 1); 559 uint64_t page; 560 uint64_t *value_ptr; 561 uint64_t min_iter = 0; 562 563 for (page = 0; page < host_num_pages; page += step) { 564 value_ptr = host_test_mem + page * host_page_size; 565 566 /* If this is a special page that we were tracking... */ 567 if (test_and_clear_bit_le(page, host_bmap_track)) { 568 host_track_next_count++; 569 TEST_ASSERT(test_bit_le(page, bmap), 570 "Page %"PRIu64" should have its dirty bit " 571 "set in this iteration but it is missing", 572 page); 573 } 574 575 if (test_and_clear_bit_le(page, bmap)) { 576 bool matched; 577 578 host_dirty_count++; 579 580 /* 581 * If the bit is set, the value written onto 582 * the corresponding page should be either the 583 * previous iteration number or the current one. 584 */ 585 matched = (*value_ptr == iteration || 586 *value_ptr == iteration - 1); 587 588 if (host_log_mode == LOG_MODE_DIRTY_RING && !matched) { 589 if (*value_ptr == iteration - 2 && min_iter <= iteration - 2) { 590 /* 591 * Short answer: this case is special 592 * only for dirty ring test where the 593 * page is the last page before a kvm 594 * dirty ring full in iteration N-2. 595 * 596 * Long answer: Assuming ring size R, 597 * one possible condition is: 598 * 599 * main thr vcpu thr 600 * -------- -------- 601 * iter=1 602 * write 1 to page 0~(R-1) 603 * full, vmexit 604 * collect 0~(R-1) 605 * kick vcpu 606 * write 1 to (R-1)~(2R-2) 607 * full, vmexit 608 * iter=2 609 * collect (R-1)~(2R-2) 610 * kick vcpu 611 * write 1 to (2R-2) 612 * (NOTE!!! "1" cached in cpu reg) 613 * write 2 to (2R-1)~(3R-3) 614 * full, vmexit 615 * iter=3 616 * collect (2R-2)~(3R-3) 617 * (here if we read value on page 618 * "2R-2" is 1, while iter=3!!!) 619 * 620 * This however can only happen once per iteration. 621 */ 622 min_iter = iteration - 1; 623 continue; 624 } else if (page == dirty_ring_last_page) { 625 /* 626 * Please refer to comments in 627 * dirty_ring_last_page. 628 */ 629 continue; 630 } 631 } 632 633 TEST_ASSERT(matched, 634 "Set page %"PRIu64" value %"PRIu64 635 " incorrect (iteration=%"PRIu64")", 636 page, *value_ptr, iteration); 637 } else { 638 host_clear_count++; 639 /* 640 * If cleared, the value written can be any 641 * value smaller or equals to the iteration 642 * number. Note that the value can be exactly 643 * (iteration-1) if that write can happen 644 * like this: 645 * 646 * (1) increase loop count to "iteration-1" 647 * (2) write to page P happens (with value 648 * "iteration-1") 649 * (3) get dirty log for "iteration-1"; we'll 650 * see that page P bit is set (dirtied), 651 * and not set the bit in host_bmap_track 652 * (4) increase loop count to "iteration" 653 * (which is current iteration) 654 * (5) get dirty log for current iteration, 655 * we'll see that page P is cleared, with 656 * value "iteration-1". 657 */ 658 TEST_ASSERT(*value_ptr <= iteration, 659 "Clear page %"PRIu64" value %"PRIu64 660 " incorrect (iteration=%"PRIu64")", 661 page, *value_ptr, iteration); 662 if (*value_ptr == iteration) { 663 /* 664 * This page is _just_ modified; it 665 * should report its dirtyness in the 666 * next run 667 */ 668 set_bit_le(page, host_bmap_track); 669 } 670 } 671 } 672 } 673 674 static struct kvm_vm *create_vm(enum vm_guest_mode mode, uint32_t vcpuid, 675 uint64_t extra_mem_pages, void *guest_code) 676 { 677 struct kvm_vm *vm; 678 uint64_t extra_pg_pages = extra_mem_pages / 512 * 2; 679 680 pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode)); 681 682 vm = vm_create(mode, DEFAULT_GUEST_PHY_PAGES + extra_pg_pages); 683 kvm_vm_elf_load(vm, program_invocation_name); 684 #ifdef __x86_64__ 685 vm_create_irqchip(vm); 686 #endif 687 log_mode_create_vm_done(vm); 688 vm_vcpu_add_default(vm, vcpuid, guest_code); 689 return vm; 690 } 691 692 #define DIRTY_MEM_BITS 30 /* 1G */ 693 #define PAGE_SHIFT_4K 12 694 695 struct test_params { 696 unsigned long iterations; 697 unsigned long interval; 698 uint64_t phys_offset; 699 }; 700 701 static void run_test(enum vm_guest_mode mode, void *arg) 702 { 703 struct test_params *p = arg; 704 struct kvm_vm *vm; 705 unsigned long *bmap; 706 707 if (!log_mode_supported()) { 708 print_skip("Log mode '%s' not supported", 709 log_modes[host_log_mode].name); 710 return; 711 } 712 713 /* 714 * We reserve page table for 2 times of extra dirty mem which 715 * will definitely cover the original (1G+) test range. Here 716 * we do the calculation with 4K page size which is the 717 * smallest so the page number will be enough for all archs 718 * (e.g., 64K page size guest will need even less memory for 719 * page tables). 720 */ 721 vm = create_vm(mode, VCPU_ID, 722 2ul << (DIRTY_MEM_BITS - PAGE_SHIFT_4K), 723 guest_code); 724 725 guest_page_size = vm_get_page_size(vm); 726 /* 727 * A little more than 1G of guest page sized pages. Cover the 728 * case where the size is not aligned to 64 pages. 729 */ 730 guest_num_pages = (1ul << (DIRTY_MEM_BITS - 731 vm_get_page_shift(vm))) + 3; 732 guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages); 733 734 host_page_size = getpagesize(); 735 host_num_pages = vm_num_host_pages(mode, guest_num_pages); 736 737 if (!p->phys_offset) { 738 guest_test_phys_mem = (vm_get_max_gfn(vm) - 739 guest_num_pages) * guest_page_size; 740 guest_test_phys_mem = align_down(guest_test_phys_mem, host_page_size); 741 } else { 742 guest_test_phys_mem = p->phys_offset; 743 } 744 745 #ifdef __s390x__ 746 /* Align to 1M (segment size) */ 747 guest_test_phys_mem = align_down(guest_test_phys_mem, 1 << 20); 748 #endif 749 750 pr_info("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem); 751 752 bmap = bitmap_zalloc(host_num_pages); 753 host_bmap_track = bitmap_zalloc(host_num_pages); 754 755 /* Add an extra memory slot for testing dirty logging */ 756 vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 757 guest_test_phys_mem, 758 TEST_MEM_SLOT_INDEX, 759 guest_num_pages, 760 KVM_MEM_LOG_DIRTY_PAGES); 761 762 /* Do mapping for the dirty track memory slot */ 763 virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, guest_num_pages); 764 765 /* Cache the HVA pointer of the region */ 766 host_test_mem = addr_gpa2hva(vm, (vm_paddr_t)guest_test_phys_mem); 767 768 ucall_init(vm, NULL); 769 770 /* Export the shared variables to the guest */ 771 sync_global_to_guest(vm, host_page_size); 772 sync_global_to_guest(vm, guest_page_size); 773 sync_global_to_guest(vm, guest_test_virt_mem); 774 sync_global_to_guest(vm, guest_num_pages); 775 776 /* Start the iterations */ 777 iteration = 1; 778 sync_global_to_guest(vm, iteration); 779 host_quit = false; 780 host_dirty_count = 0; 781 host_clear_count = 0; 782 host_track_next_count = 0; 783 784 pthread_create(&vcpu_thread, NULL, vcpu_worker, vm); 785 786 while (iteration < p->iterations) { 787 /* Give the vcpu thread some time to dirty some pages */ 788 usleep(p->interval * 1000); 789 log_mode_collect_dirty_pages(vm, TEST_MEM_SLOT_INDEX, 790 bmap, host_num_pages); 791 792 /* 793 * See vcpu_sync_stop_requested definition for details on why 794 * we need to stop vcpu when verify data. 795 */ 796 atomic_set(&vcpu_sync_stop_requested, true); 797 sem_wait_until(&sem_vcpu_stop); 798 /* 799 * NOTE: for dirty ring, it's possible that we didn't stop at 800 * GUEST_SYNC but instead we stopped because ring is full; 801 * that's okay too because ring full means we're only missing 802 * the flush of the last page, and since we handle the last 803 * page specially verification will succeed anyway. 804 */ 805 assert(host_log_mode == LOG_MODE_DIRTY_RING || 806 atomic_read(&vcpu_sync_stop_requested) == false); 807 vm_dirty_log_verify(mode, bmap); 808 sem_post(&sem_vcpu_cont); 809 810 iteration++; 811 sync_global_to_guest(vm, iteration); 812 } 813 814 /* Tell the vcpu thread to quit */ 815 host_quit = true; 816 log_mode_before_vcpu_join(); 817 pthread_join(vcpu_thread, NULL); 818 819 pr_info("Total bits checked: dirty (%"PRIu64"), clear (%"PRIu64"), " 820 "track_next (%"PRIu64")\n", host_dirty_count, host_clear_count, 821 host_track_next_count); 822 823 free(bmap); 824 free(host_bmap_track); 825 ucall_uninit(vm); 826 kvm_vm_free(vm); 827 } 828 829 static void help(char *name) 830 { 831 puts(""); 832 printf("usage: %s [-h] [-i iterations] [-I interval] " 833 "[-p offset] [-m mode]\n", name); 834 puts(""); 835 printf(" -c: specify dirty ring size, in number of entries\n"); 836 printf(" (only useful for dirty-ring test; default: %"PRIu32")\n", 837 TEST_DIRTY_RING_COUNT); 838 printf(" -i: specify iteration counts (default: %"PRIu64")\n", 839 TEST_HOST_LOOP_N); 840 printf(" -I: specify interval in ms (default: %"PRIu64" ms)\n", 841 TEST_HOST_LOOP_INTERVAL); 842 printf(" -p: specify guest physical test memory offset\n" 843 " Warning: a low offset can conflict with the loaded test code.\n"); 844 printf(" -M: specify the host logging mode " 845 "(default: run all log modes). Supported modes: \n\t"); 846 log_modes_dump(); 847 guest_modes_help(); 848 puts(""); 849 exit(0); 850 } 851 852 int main(int argc, char *argv[]) 853 { 854 struct test_params p = { 855 .iterations = TEST_HOST_LOOP_N, 856 .interval = TEST_HOST_LOOP_INTERVAL, 857 }; 858 int opt, i; 859 sigset_t sigset; 860 861 sem_init(&sem_vcpu_stop, 0, 0); 862 sem_init(&sem_vcpu_cont, 0, 0); 863 864 guest_modes_append_default(); 865 866 while ((opt = getopt(argc, argv, "c:hi:I:p:m:M:")) != -1) { 867 switch (opt) { 868 case 'c': 869 test_dirty_ring_count = strtol(optarg, NULL, 10); 870 break; 871 case 'i': 872 p.iterations = strtol(optarg, NULL, 10); 873 break; 874 case 'I': 875 p.interval = strtol(optarg, NULL, 10); 876 break; 877 case 'p': 878 p.phys_offset = strtoull(optarg, NULL, 0); 879 break; 880 case 'm': 881 guest_modes_cmdline(optarg); 882 break; 883 case 'M': 884 if (!strcmp(optarg, "all")) { 885 host_log_mode_option = LOG_MODE_ALL; 886 break; 887 } 888 for (i = 0; i < LOG_MODE_NUM; i++) { 889 if (!strcmp(optarg, log_modes[i].name)) { 890 pr_info("Setting log mode to: '%s'\n", 891 optarg); 892 host_log_mode_option = i; 893 break; 894 } 895 } 896 if (i == LOG_MODE_NUM) { 897 printf("Log mode '%s' invalid. Please choose " 898 "from: ", optarg); 899 log_modes_dump(); 900 exit(1); 901 } 902 break; 903 case 'h': 904 default: 905 help(argv[0]); 906 break; 907 } 908 } 909 910 TEST_ASSERT(p.iterations > 2, "Iterations must be greater than two"); 911 TEST_ASSERT(p.interval > 0, "Interval must be greater than zero"); 912 913 pr_info("Test iterations: %"PRIu64", interval: %"PRIu64" (ms)\n", 914 p.iterations, p.interval); 915 916 srandom(time(0)); 917 918 /* Ensure that vCPU threads start with SIG_IPI blocked. */ 919 sigemptyset(&sigset); 920 sigaddset(&sigset, SIG_IPI); 921 pthread_sigmask(SIG_BLOCK, &sigset, NULL); 922 923 if (host_log_mode_option == LOG_MODE_ALL) { 924 /* Run each log mode */ 925 for (i = 0; i < LOG_MODE_NUM; i++) { 926 pr_info("Testing Log Mode '%s'\n", log_modes[i].name); 927 host_log_mode = i; 928 for_each_guest_mode(run_test, &p); 929 } 930 } else { 931 host_log_mode = host_log_mode_option; 932 for_each_guest_mode(run_test, &p); 933 } 934 935 return 0; 936 } 937