1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * KVM dirty page logging performance test 4 * 5 * Based on dirty_log_test.c 6 * 7 * Copyright (C) 2018, Red Hat, Inc. 8 * Copyright (C) 2020, Google, Inc. 9 */ 10 11 #include <stdio.h> 12 #include <stdlib.h> 13 #include <time.h> 14 #include <pthread.h> 15 #include <linux/bitmap.h> 16 17 #include "kvm_util.h" 18 #include "test_util.h" 19 #include "perf_test_util.h" 20 #include "guest_modes.h" 21 #ifdef __aarch64__ 22 #include "aarch64/vgic.h" 23 24 #define GICD_BASE_GPA 0x8000000ULL 25 #define GICR_BASE_GPA 0x80A0000ULL 26 #endif 27 28 /* How many host loops to run by default (one KVM_GET_DIRTY_LOG for each loop)*/ 29 #define TEST_HOST_LOOP_N 2UL 30 31 static int nr_vcpus = 1; 32 static uint64_t guest_percpu_mem_size = DEFAULT_PER_VCPU_MEM_SIZE; 33 34 /* Host variables */ 35 static u64 dirty_log_manual_caps; 36 static bool host_quit; 37 static int iteration; 38 static int vcpu_last_completed_iteration[KVM_MAX_VCPUS]; 39 40 static void vcpu_worker(struct perf_test_vcpu_args *vcpu_args) 41 { 42 int ret; 43 struct kvm_vm *vm = perf_test_args.vm; 44 uint64_t pages_count = 0; 45 struct kvm_run *run; 46 struct timespec start; 47 struct timespec ts_diff; 48 struct timespec total = (struct timespec){0}; 49 struct timespec avg; 50 int vcpu_id = vcpu_args->vcpu_id; 51 52 run = vcpu_state(vm, vcpu_id); 53 54 while (!READ_ONCE(host_quit)) { 55 int current_iteration = READ_ONCE(iteration); 56 57 clock_gettime(CLOCK_MONOTONIC, &start); 58 ret = _vcpu_run(vm, vcpu_id); 59 ts_diff = timespec_elapsed(start); 60 61 TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret); 62 TEST_ASSERT(get_ucall(vm, vcpu_id, NULL) == UCALL_SYNC, 63 "Invalid guest sync status: exit_reason=%s\n", 64 exit_reason_str(run->exit_reason)); 65 66 pr_debug("Got sync event from vCPU %d\n", vcpu_id); 67 vcpu_last_completed_iteration[vcpu_id] = current_iteration; 68 pr_debug("vCPU %d updated last completed iteration to %d\n", 69 vcpu_id, vcpu_last_completed_iteration[vcpu_id]); 70 71 if (current_iteration) { 72 pages_count += vcpu_args->pages; 73 total = timespec_add(total, ts_diff); 74 pr_debug("vCPU %d iteration %d dirty memory time: %ld.%.9lds\n", 75 vcpu_id, current_iteration, ts_diff.tv_sec, 76 ts_diff.tv_nsec); 77 } else { 78 pr_debug("vCPU %d iteration %d populate memory time: %ld.%.9lds\n", 79 vcpu_id, current_iteration, ts_diff.tv_sec, 80 ts_diff.tv_nsec); 81 } 82 83 while (current_iteration == READ_ONCE(iteration) && 84 !READ_ONCE(host_quit)) {} 85 } 86 87 avg = timespec_div(total, vcpu_last_completed_iteration[vcpu_id]); 88 pr_debug("\nvCPU %d dirtied 0x%lx pages over %d iterations in %ld.%.9lds. (Avg %ld.%.9lds/iteration)\n", 89 vcpu_id, pages_count, vcpu_last_completed_iteration[vcpu_id], 90 total.tv_sec, total.tv_nsec, avg.tv_sec, avg.tv_nsec); 91 } 92 93 struct test_params { 94 unsigned long iterations; 95 uint64_t phys_offset; 96 int wr_fract; 97 bool partition_vcpu_memory_access; 98 enum vm_mem_backing_src_type backing_src; 99 int slots; 100 }; 101 102 static void toggle_dirty_logging(struct kvm_vm *vm, int slots, bool enable) 103 { 104 int i; 105 106 for (i = 0; i < slots; i++) { 107 int slot = PERF_TEST_MEM_SLOT_INDEX + i; 108 int flags = enable ? KVM_MEM_LOG_DIRTY_PAGES : 0; 109 110 vm_mem_region_set_flags(vm, slot, flags); 111 } 112 } 113 114 static inline void enable_dirty_logging(struct kvm_vm *vm, int slots) 115 { 116 toggle_dirty_logging(vm, slots, true); 117 } 118 119 static inline void disable_dirty_logging(struct kvm_vm *vm, int slots) 120 { 121 toggle_dirty_logging(vm, slots, false); 122 } 123 124 static void get_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[], int slots) 125 { 126 int i; 127 128 for (i = 0; i < slots; i++) { 129 int slot = PERF_TEST_MEM_SLOT_INDEX + i; 130 131 kvm_vm_get_dirty_log(vm, slot, bitmaps[i]); 132 } 133 } 134 135 static void clear_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[], 136 int slots, uint64_t pages_per_slot) 137 { 138 int i; 139 140 for (i = 0; i < slots; i++) { 141 int slot = PERF_TEST_MEM_SLOT_INDEX + i; 142 143 kvm_vm_clear_dirty_log(vm, slot, bitmaps[i], 0, pages_per_slot); 144 } 145 } 146 147 static unsigned long **alloc_bitmaps(int slots, uint64_t pages_per_slot) 148 { 149 unsigned long **bitmaps; 150 int i; 151 152 bitmaps = malloc(slots * sizeof(bitmaps[0])); 153 TEST_ASSERT(bitmaps, "Failed to allocate bitmaps array."); 154 155 for (i = 0; i < slots; i++) { 156 bitmaps[i] = bitmap_zalloc(pages_per_slot); 157 TEST_ASSERT(bitmaps[i], "Failed to allocate slot bitmap."); 158 } 159 160 return bitmaps; 161 } 162 163 static void free_bitmaps(unsigned long *bitmaps[], int slots) 164 { 165 int i; 166 167 for (i = 0; i < slots; i++) 168 free(bitmaps[i]); 169 170 free(bitmaps); 171 } 172 173 static void run_test(enum vm_guest_mode mode, void *arg) 174 { 175 struct test_params *p = arg; 176 struct kvm_vm *vm; 177 unsigned long **bitmaps; 178 uint64_t guest_num_pages; 179 uint64_t host_num_pages; 180 uint64_t pages_per_slot; 181 int vcpu_id; 182 struct timespec start; 183 struct timespec ts_diff; 184 struct timespec get_dirty_log_total = (struct timespec){0}; 185 struct timespec vcpu_dirty_total = (struct timespec){0}; 186 struct timespec avg; 187 struct kvm_enable_cap cap = {}; 188 struct timespec clear_dirty_log_total = (struct timespec){0}; 189 190 vm = perf_test_create_vm(mode, nr_vcpus, guest_percpu_mem_size, 191 p->slots, p->backing_src, 192 p->partition_vcpu_memory_access); 193 194 perf_test_set_wr_fract(vm, p->wr_fract); 195 196 guest_num_pages = (nr_vcpus * guest_percpu_mem_size) >> vm_get_page_shift(vm); 197 guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages); 198 host_num_pages = vm_num_host_pages(mode, guest_num_pages); 199 pages_per_slot = host_num_pages / p->slots; 200 201 bitmaps = alloc_bitmaps(p->slots, pages_per_slot); 202 203 if (dirty_log_manual_caps) { 204 cap.cap = KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2; 205 cap.args[0] = dirty_log_manual_caps; 206 vm_enable_cap(vm, &cap); 207 } 208 209 #ifdef __aarch64__ 210 vgic_v3_setup(vm, nr_vcpus, 64, GICD_BASE_GPA, GICR_BASE_GPA); 211 #endif 212 213 /* Start the iterations */ 214 iteration = 0; 215 host_quit = false; 216 217 clock_gettime(CLOCK_MONOTONIC, &start); 218 for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) 219 vcpu_last_completed_iteration[vcpu_id] = -1; 220 221 perf_test_start_vcpu_threads(nr_vcpus, vcpu_worker); 222 223 /* Allow the vCPUs to populate memory */ 224 pr_debug("Starting iteration %d - Populating\n", iteration); 225 for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) { 226 while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) != 227 iteration) 228 ; 229 } 230 231 ts_diff = timespec_elapsed(start); 232 pr_info("Populate memory time: %ld.%.9lds\n", 233 ts_diff.tv_sec, ts_diff.tv_nsec); 234 235 /* Enable dirty logging */ 236 clock_gettime(CLOCK_MONOTONIC, &start); 237 enable_dirty_logging(vm, p->slots); 238 ts_diff = timespec_elapsed(start); 239 pr_info("Enabling dirty logging time: %ld.%.9lds\n\n", 240 ts_diff.tv_sec, ts_diff.tv_nsec); 241 242 while (iteration < p->iterations) { 243 /* 244 * Incrementing the iteration number will start the vCPUs 245 * dirtying memory again. 246 */ 247 clock_gettime(CLOCK_MONOTONIC, &start); 248 iteration++; 249 250 pr_debug("Starting iteration %d\n", iteration); 251 for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) { 252 while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) 253 != iteration) 254 ; 255 } 256 257 ts_diff = timespec_elapsed(start); 258 vcpu_dirty_total = timespec_add(vcpu_dirty_total, ts_diff); 259 pr_info("Iteration %d dirty memory time: %ld.%.9lds\n", 260 iteration, ts_diff.tv_sec, ts_diff.tv_nsec); 261 262 clock_gettime(CLOCK_MONOTONIC, &start); 263 get_dirty_log(vm, bitmaps, p->slots); 264 ts_diff = timespec_elapsed(start); 265 get_dirty_log_total = timespec_add(get_dirty_log_total, 266 ts_diff); 267 pr_info("Iteration %d get dirty log time: %ld.%.9lds\n", 268 iteration, ts_diff.tv_sec, ts_diff.tv_nsec); 269 270 if (dirty_log_manual_caps) { 271 clock_gettime(CLOCK_MONOTONIC, &start); 272 clear_dirty_log(vm, bitmaps, p->slots, pages_per_slot); 273 ts_diff = timespec_elapsed(start); 274 clear_dirty_log_total = timespec_add(clear_dirty_log_total, 275 ts_diff); 276 pr_info("Iteration %d clear dirty log time: %ld.%.9lds\n", 277 iteration, ts_diff.tv_sec, ts_diff.tv_nsec); 278 } 279 } 280 281 /* Disable dirty logging */ 282 clock_gettime(CLOCK_MONOTONIC, &start); 283 disable_dirty_logging(vm, p->slots); 284 ts_diff = timespec_elapsed(start); 285 pr_info("Disabling dirty logging time: %ld.%.9lds\n", 286 ts_diff.tv_sec, ts_diff.tv_nsec); 287 288 /* Tell the vcpu thread to quit */ 289 host_quit = true; 290 perf_test_join_vcpu_threads(nr_vcpus); 291 292 avg = timespec_div(get_dirty_log_total, p->iterations); 293 pr_info("Get dirty log over %lu iterations took %ld.%.9lds. (Avg %ld.%.9lds/iteration)\n", 294 p->iterations, get_dirty_log_total.tv_sec, 295 get_dirty_log_total.tv_nsec, avg.tv_sec, avg.tv_nsec); 296 297 if (dirty_log_manual_caps) { 298 avg = timespec_div(clear_dirty_log_total, p->iterations); 299 pr_info("Clear dirty log over %lu iterations took %ld.%.9lds. (Avg %ld.%.9lds/iteration)\n", 300 p->iterations, clear_dirty_log_total.tv_sec, 301 clear_dirty_log_total.tv_nsec, avg.tv_sec, avg.tv_nsec); 302 } 303 304 free_bitmaps(bitmaps, p->slots); 305 perf_test_destroy_vm(vm); 306 } 307 308 static void help(char *name) 309 { 310 puts(""); 311 printf("usage: %s [-h] [-i iterations] [-p offset] " 312 "[-m mode] [-b vcpu bytes] [-v vcpus] [-o] [-s mem type]" 313 "[-x memslots]\n", name); 314 puts(""); 315 printf(" -i: specify iteration counts (default: %"PRIu64")\n", 316 TEST_HOST_LOOP_N); 317 printf(" -p: specify guest physical test memory offset\n" 318 " Warning: a low offset can conflict with the loaded test code.\n"); 319 guest_modes_help(); 320 printf(" -b: specify the size of the memory region which should be\n" 321 " dirtied by each vCPU. e.g. 10M or 3G.\n" 322 " (default: 1G)\n"); 323 printf(" -f: specify the fraction of pages which should be written to\n" 324 " as opposed to simply read, in the form\n" 325 " 1/<fraction of pages to write>.\n" 326 " (default: 1 i.e. all pages are written to.)\n"); 327 printf(" -v: specify the number of vCPUs to run.\n"); 328 printf(" -o: Overlap guest memory accesses instead of partitioning\n" 329 " them into a separate region of memory for each vCPU.\n"); 330 backing_src_help("-s"); 331 printf(" -x: Split the memory region into this number of memslots.\n" 332 " (default: 1)\n"); 333 puts(""); 334 exit(0); 335 } 336 337 int main(int argc, char *argv[]) 338 { 339 int max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS); 340 struct test_params p = { 341 .iterations = TEST_HOST_LOOP_N, 342 .wr_fract = 1, 343 .partition_vcpu_memory_access = true, 344 .backing_src = DEFAULT_VM_MEM_SRC, 345 .slots = 1, 346 }; 347 int opt; 348 349 dirty_log_manual_caps = 350 kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2); 351 dirty_log_manual_caps &= (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE | 352 KVM_DIRTY_LOG_INITIALLY_SET); 353 354 guest_modes_append_default(); 355 356 while ((opt = getopt(argc, argv, "hi:p:m:b:f:v:os:x:")) != -1) { 357 switch (opt) { 358 case 'i': 359 p.iterations = atoi(optarg); 360 break; 361 case 'p': 362 p.phys_offset = strtoull(optarg, NULL, 0); 363 break; 364 case 'm': 365 guest_modes_cmdline(optarg); 366 break; 367 case 'b': 368 guest_percpu_mem_size = parse_size(optarg); 369 break; 370 case 'f': 371 p.wr_fract = atoi(optarg); 372 TEST_ASSERT(p.wr_fract >= 1, 373 "Write fraction cannot be less than one"); 374 break; 375 case 'v': 376 nr_vcpus = atoi(optarg); 377 TEST_ASSERT(nr_vcpus > 0 && nr_vcpus <= max_vcpus, 378 "Invalid number of vcpus, must be between 1 and %d", max_vcpus); 379 break; 380 case 'o': 381 p.partition_vcpu_memory_access = false; 382 break; 383 case 's': 384 p.backing_src = parse_backing_src_type(optarg); 385 break; 386 case 'x': 387 p.slots = atoi(optarg); 388 break; 389 case 'h': 390 default: 391 help(argv[0]); 392 break; 393 } 394 } 395 396 TEST_ASSERT(p.iterations >= 2, "The test should have at least two iterations"); 397 398 pr_info("Test iterations: %"PRIu64"\n", p.iterations); 399 400 for_each_guest_mode(run_test, &p); 401 402 return 0; 403 } 404