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