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 #define _GNU_SOURCE /* for program_invocation_name */ 12 13 #include <stdio.h> 14 #include <stdlib.h> 15 #include <unistd.h> 16 #include <time.h> 17 #include <pthread.h> 18 #include <linux/bitmap.h> 19 #include <linux/bitops.h> 20 21 #include "kvm_util.h" 22 #include "perf_test_util.h" 23 #include "processor.h" 24 #include "test_util.h" 25 26 /* How many host loops to run by default (one KVM_GET_DIRTY_LOG for each loop)*/ 27 #define TEST_HOST_LOOP_N 2UL 28 29 /* Host variables */ 30 static bool host_quit; 31 static uint64_t iteration; 32 static uint64_t vcpu_last_completed_iteration[MAX_VCPUS]; 33 34 static void *vcpu_worker(void *data) 35 { 36 int ret; 37 struct kvm_vm *vm = perf_test_args.vm; 38 uint64_t pages_count = 0; 39 struct kvm_run *run; 40 struct timespec start; 41 struct timespec ts_diff; 42 struct timespec total = (struct timespec){0}; 43 struct timespec avg; 44 struct vcpu_args *vcpu_args = (struct vcpu_args *)data; 45 int vcpu_id = vcpu_args->vcpu_id; 46 47 vcpu_args_set(vm, vcpu_id, 1, vcpu_id); 48 run = vcpu_state(vm, vcpu_id); 49 50 while (!READ_ONCE(host_quit)) { 51 uint64_t current_iteration = READ_ONCE(iteration); 52 53 clock_gettime(CLOCK_MONOTONIC, &start); 54 ret = _vcpu_run(vm, vcpu_id); 55 ts_diff = timespec_diff_now(start); 56 57 TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret); 58 TEST_ASSERT(get_ucall(vm, vcpu_id, NULL) == UCALL_SYNC, 59 "Invalid guest sync status: exit_reason=%s\n", 60 exit_reason_str(run->exit_reason)); 61 62 pr_debug("Got sync event from vCPU %d\n", vcpu_id); 63 vcpu_last_completed_iteration[vcpu_id] = current_iteration; 64 pr_debug("vCPU %d updated last completed iteration to %lu\n", 65 vcpu_id, vcpu_last_completed_iteration[vcpu_id]); 66 67 if (current_iteration) { 68 pages_count += vcpu_args->pages; 69 total = timespec_add(total, ts_diff); 70 pr_debug("vCPU %d iteration %lu dirty memory time: %ld.%.9lds\n", 71 vcpu_id, current_iteration, ts_diff.tv_sec, 72 ts_diff.tv_nsec); 73 } else { 74 pr_debug("vCPU %d iteration %lu populate memory time: %ld.%.9lds\n", 75 vcpu_id, current_iteration, ts_diff.tv_sec, 76 ts_diff.tv_nsec); 77 } 78 79 while (current_iteration == READ_ONCE(iteration) && 80 !READ_ONCE(host_quit)) {} 81 } 82 83 avg = timespec_div(total, vcpu_last_completed_iteration[vcpu_id]); 84 pr_debug("\nvCPU %d dirtied 0x%lx pages over %lu iterations in %ld.%.9lds. (Avg %ld.%.9lds/iteration)\n", 85 vcpu_id, pages_count, vcpu_last_completed_iteration[vcpu_id], 86 total.tv_sec, total.tv_nsec, avg.tv_sec, avg.tv_nsec); 87 88 return NULL; 89 } 90 91 #ifdef USE_CLEAR_DIRTY_LOG 92 static u64 dirty_log_manual_caps; 93 #endif 94 95 static void run_test(enum vm_guest_mode mode, unsigned long iterations, 96 uint64_t phys_offset, int wr_fract) 97 { 98 pthread_t *vcpu_threads; 99 struct kvm_vm *vm; 100 unsigned long *bmap; 101 uint64_t guest_num_pages; 102 uint64_t host_num_pages; 103 int vcpu_id; 104 struct timespec start; 105 struct timespec ts_diff; 106 struct timespec get_dirty_log_total = (struct timespec){0}; 107 struct timespec vcpu_dirty_total = (struct timespec){0}; 108 struct timespec avg; 109 #ifdef USE_CLEAR_DIRTY_LOG 110 struct kvm_enable_cap cap = {}; 111 struct timespec clear_dirty_log_total = (struct timespec){0}; 112 #endif 113 114 vm = create_vm(mode, nr_vcpus, guest_percpu_mem_size); 115 116 perf_test_args.wr_fract = wr_fract; 117 118 guest_num_pages = (nr_vcpus * guest_percpu_mem_size) >> vm_get_page_shift(vm); 119 guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages); 120 host_num_pages = vm_num_host_pages(mode, guest_num_pages); 121 bmap = bitmap_alloc(host_num_pages); 122 123 #ifdef USE_CLEAR_DIRTY_LOG 124 cap.cap = KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2; 125 cap.args[0] = dirty_log_manual_caps; 126 vm_enable_cap(vm, &cap); 127 #endif 128 129 vcpu_threads = malloc(nr_vcpus * sizeof(*vcpu_threads)); 130 TEST_ASSERT(vcpu_threads, "Memory allocation failed"); 131 132 add_vcpus(vm, nr_vcpus, guest_percpu_mem_size); 133 134 sync_global_to_guest(vm, perf_test_args); 135 136 /* Start the iterations */ 137 iteration = 0; 138 host_quit = false; 139 140 clock_gettime(CLOCK_MONOTONIC, &start); 141 for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) { 142 pthread_create(&vcpu_threads[vcpu_id], NULL, vcpu_worker, 143 &perf_test_args.vcpu_args[vcpu_id]); 144 } 145 146 /* Allow the vCPU to populate memory */ 147 pr_debug("Starting iteration %lu - Populating\n", iteration); 148 while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) != iteration) 149 pr_debug("Waiting for vcpu_last_completed_iteration == %lu\n", 150 iteration); 151 152 ts_diff = timespec_diff_now(start); 153 pr_info("Populate memory time: %ld.%.9lds\n", 154 ts_diff.tv_sec, ts_diff.tv_nsec); 155 156 /* Enable dirty logging */ 157 clock_gettime(CLOCK_MONOTONIC, &start); 158 vm_mem_region_set_flags(vm, TEST_MEM_SLOT_INDEX, 159 KVM_MEM_LOG_DIRTY_PAGES); 160 ts_diff = timespec_diff_now(start); 161 pr_info("Enabling dirty logging time: %ld.%.9lds\n\n", 162 ts_diff.tv_sec, ts_diff.tv_nsec); 163 164 while (iteration < iterations) { 165 /* 166 * Incrementing the iteration number will start the vCPUs 167 * dirtying memory again. 168 */ 169 clock_gettime(CLOCK_MONOTONIC, &start); 170 iteration++; 171 172 pr_debug("Starting iteration %lu\n", iteration); 173 for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) { 174 while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) != iteration) 175 pr_debug("Waiting for vCPU %d vcpu_last_completed_iteration == %lu\n", 176 vcpu_id, iteration); 177 } 178 179 ts_diff = timespec_diff_now(start); 180 vcpu_dirty_total = timespec_add(vcpu_dirty_total, ts_diff); 181 pr_info("Iteration %lu dirty memory time: %ld.%.9lds\n", 182 iteration, ts_diff.tv_sec, ts_diff.tv_nsec); 183 184 clock_gettime(CLOCK_MONOTONIC, &start); 185 kvm_vm_get_dirty_log(vm, TEST_MEM_SLOT_INDEX, bmap); 186 187 ts_diff = timespec_diff_now(start); 188 get_dirty_log_total = timespec_add(get_dirty_log_total, 189 ts_diff); 190 pr_info("Iteration %lu get dirty log time: %ld.%.9lds\n", 191 iteration, ts_diff.tv_sec, ts_diff.tv_nsec); 192 193 #ifdef USE_CLEAR_DIRTY_LOG 194 clock_gettime(CLOCK_MONOTONIC, &start); 195 kvm_vm_clear_dirty_log(vm, TEST_MEM_SLOT_INDEX, bmap, 0, 196 host_num_pages); 197 198 ts_diff = timespec_diff_now(start); 199 clear_dirty_log_total = timespec_add(clear_dirty_log_total, 200 ts_diff); 201 pr_info("Iteration %lu clear dirty log time: %ld.%.9lds\n", 202 iteration, ts_diff.tv_sec, ts_diff.tv_nsec); 203 #endif 204 } 205 206 /* Tell the vcpu thread to quit */ 207 host_quit = true; 208 for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) 209 pthread_join(vcpu_threads[vcpu_id], NULL); 210 211 /* Disable dirty logging */ 212 clock_gettime(CLOCK_MONOTONIC, &start); 213 vm_mem_region_set_flags(vm, TEST_MEM_SLOT_INDEX, 0); 214 ts_diff = timespec_diff_now(start); 215 pr_info("Disabling dirty logging time: %ld.%.9lds\n", 216 ts_diff.tv_sec, ts_diff.tv_nsec); 217 218 avg = timespec_div(get_dirty_log_total, iterations); 219 pr_info("Get dirty log over %lu iterations took %ld.%.9lds. (Avg %ld.%.9lds/iteration)\n", 220 iterations, get_dirty_log_total.tv_sec, 221 get_dirty_log_total.tv_nsec, avg.tv_sec, avg.tv_nsec); 222 223 #ifdef USE_CLEAR_DIRTY_LOG 224 avg = timespec_div(clear_dirty_log_total, iterations); 225 pr_info("Clear dirty log over %lu iterations took %ld.%.9lds. (Avg %ld.%.9lds/iteration)\n", 226 iterations, clear_dirty_log_total.tv_sec, 227 clear_dirty_log_total.tv_nsec, avg.tv_sec, avg.tv_nsec); 228 #endif 229 230 free(bmap); 231 free(vcpu_threads); 232 ucall_uninit(vm); 233 kvm_vm_free(vm); 234 } 235 236 struct guest_mode { 237 bool supported; 238 bool enabled; 239 }; 240 static struct guest_mode guest_modes[NUM_VM_MODES]; 241 242 #define guest_mode_init(mode, supported, enabled) ({ \ 243 guest_modes[mode] = (struct guest_mode){ supported, enabled }; \ 244 }) 245 246 static void help(char *name) 247 { 248 int i; 249 250 puts(""); 251 printf("usage: %s [-h] [-i iterations] [-p offset] " 252 "[-m mode] [-b vcpu bytes] [-v vcpus]\n", name); 253 puts(""); 254 printf(" -i: specify iteration counts (default: %"PRIu64")\n", 255 TEST_HOST_LOOP_N); 256 printf(" -p: specify guest physical test memory offset\n" 257 " Warning: a low offset can conflict with the loaded test code.\n"); 258 printf(" -m: specify the guest mode ID to test " 259 "(default: test all supported modes)\n" 260 " This option may be used multiple times.\n" 261 " Guest mode IDs:\n"); 262 for (i = 0; i < NUM_VM_MODES; ++i) { 263 printf(" %d: %s%s\n", i, vm_guest_mode_string(i), 264 guest_modes[i].supported ? " (supported)" : ""); 265 } 266 printf(" -b: specify the size of the memory region which should be\n" 267 " dirtied by each vCPU. e.g. 10M or 3G.\n" 268 " (default: 1G)\n"); 269 printf(" -f: specify the fraction of pages which should be written to\n" 270 " as opposed to simply read, in the form\n" 271 " 1/<fraction of pages to write>.\n" 272 " (default: 1 i.e. all pages are written to.)\n"); 273 printf(" -v: specify the number of vCPUs to run.\n"); 274 puts(""); 275 exit(0); 276 } 277 278 int main(int argc, char *argv[]) 279 { 280 unsigned long iterations = TEST_HOST_LOOP_N; 281 bool mode_selected = false; 282 uint64_t phys_offset = 0; 283 unsigned int mode; 284 int opt, i; 285 int wr_fract = 1; 286 287 #ifdef USE_CLEAR_DIRTY_LOG 288 dirty_log_manual_caps = 289 kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2); 290 if (!dirty_log_manual_caps) { 291 print_skip("KVM_CLEAR_DIRTY_LOG not available"); 292 exit(KSFT_SKIP); 293 } 294 dirty_log_manual_caps &= (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE | 295 KVM_DIRTY_LOG_INITIALLY_SET); 296 #endif 297 298 #ifdef __x86_64__ 299 guest_mode_init(VM_MODE_PXXV48_4K, true, true); 300 #endif 301 #ifdef __aarch64__ 302 guest_mode_init(VM_MODE_P40V48_4K, true, true); 303 guest_mode_init(VM_MODE_P40V48_64K, true, true); 304 305 { 306 unsigned int limit = kvm_check_cap(KVM_CAP_ARM_VM_IPA_SIZE); 307 308 if (limit >= 52) 309 guest_mode_init(VM_MODE_P52V48_64K, true, true); 310 if (limit >= 48) { 311 guest_mode_init(VM_MODE_P48V48_4K, true, true); 312 guest_mode_init(VM_MODE_P48V48_64K, true, true); 313 } 314 } 315 #endif 316 #ifdef __s390x__ 317 guest_mode_init(VM_MODE_P40V48_4K, true, true); 318 #endif 319 320 while ((opt = getopt(argc, argv, "hi:p:m:b:f:v:")) != -1) { 321 switch (opt) { 322 case 'i': 323 iterations = strtol(optarg, NULL, 10); 324 break; 325 case 'p': 326 phys_offset = strtoull(optarg, NULL, 0); 327 break; 328 case 'm': 329 if (!mode_selected) { 330 for (i = 0; i < NUM_VM_MODES; ++i) 331 guest_modes[i].enabled = false; 332 mode_selected = true; 333 } 334 mode = strtoul(optarg, NULL, 10); 335 TEST_ASSERT(mode < NUM_VM_MODES, 336 "Guest mode ID %d too big", mode); 337 guest_modes[mode].enabled = true; 338 break; 339 case 'b': 340 guest_percpu_mem_size = parse_size(optarg); 341 break; 342 case 'f': 343 wr_fract = atoi(optarg); 344 TEST_ASSERT(wr_fract >= 1, 345 "Write fraction cannot be less than one"); 346 break; 347 case 'v': 348 nr_vcpus = atoi(optarg); 349 TEST_ASSERT(nr_vcpus > 0, 350 "Must have a positive number of vCPUs"); 351 TEST_ASSERT(nr_vcpus <= MAX_VCPUS, 352 "This test does not currently support\n" 353 "more than %d vCPUs.", MAX_VCPUS); 354 break; 355 case 'h': 356 default: 357 help(argv[0]); 358 break; 359 } 360 } 361 362 TEST_ASSERT(iterations >= 2, "The test should have at least two iterations"); 363 364 pr_info("Test iterations: %"PRIu64"\n", iterations); 365 366 for (i = 0; i < NUM_VM_MODES; ++i) { 367 if (!guest_modes[i].enabled) 368 continue; 369 TEST_ASSERT(guest_modes[i].supported, 370 "Guest mode ID %d (%s) not supported.", 371 i, vm_guest_mode_string(i)); 372 run_test(i, iterations, phys_offset, wr_fract); 373 } 374 375 return 0; 376 } 377