1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * KVM memslot modification stress test 4 * Adapted from demand_paging_test.c 5 * 6 * Copyright (C) 2018, Red Hat, Inc. 7 * Copyright (C) 2020, Google, Inc. 8 */ 9 10 #define _GNU_SOURCE /* for program_invocation_name */ 11 12 #include <stdio.h> 13 #include <stdlib.h> 14 #include <sys/syscall.h> 15 #include <unistd.h> 16 #include <asm/unistd.h> 17 #include <time.h> 18 #include <poll.h> 19 #include <pthread.h> 20 #include <linux/bitmap.h> 21 #include <linux/bitops.h> 22 #include <linux/userfaultfd.h> 23 24 #include "perf_test_util.h" 25 #include "processor.h" 26 #include "test_util.h" 27 #include "guest_modes.h" 28 29 #define DUMMY_MEMSLOT_INDEX 7 30 31 #define DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS 10 32 33 34 static int nr_vcpus = 1; 35 static uint64_t guest_percpu_mem_size = DEFAULT_PER_VCPU_MEM_SIZE; 36 37 static bool run_vcpus = true; 38 39 static void *vcpu_worker(void *data) 40 { 41 int ret; 42 struct perf_test_vcpu_args *vcpu_args = 43 (struct perf_test_vcpu_args *)data; 44 int vcpu_id = vcpu_args->vcpu_id; 45 struct kvm_vm *vm = perf_test_args.vm; 46 struct kvm_run *run; 47 48 vcpu_args_set(vm, vcpu_id, 1, vcpu_id); 49 run = vcpu_state(vm, vcpu_id); 50 51 /* Let the guest access its memory until a stop signal is received */ 52 while (READ_ONCE(run_vcpus)) { 53 ret = _vcpu_run(vm, vcpu_id); 54 TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret); 55 56 if (get_ucall(vm, vcpu_id, NULL) == UCALL_SYNC) 57 continue; 58 59 TEST_ASSERT(false, 60 "Invalid guest sync status: exit_reason=%s\n", 61 exit_reason_str(run->exit_reason)); 62 } 63 64 return NULL; 65 } 66 67 struct memslot_antagonist_args { 68 struct kvm_vm *vm; 69 useconds_t delay; 70 uint64_t nr_modifications; 71 }; 72 73 static void add_remove_memslot(struct kvm_vm *vm, useconds_t delay, 74 uint64_t nr_modifications) 75 { 76 const uint64_t pages = 1; 77 uint64_t gpa; 78 int i; 79 80 /* 81 * Add the dummy memslot just below the perf_test_util memslot, which is 82 * at the top of the guest physical address space. 83 */ 84 gpa = guest_test_phys_mem - pages * vm_get_page_size(vm); 85 86 for (i = 0; i < nr_modifications; i++) { 87 usleep(delay); 88 vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, gpa, 89 DUMMY_MEMSLOT_INDEX, pages, 0); 90 91 vm_mem_region_delete(vm, DUMMY_MEMSLOT_INDEX); 92 } 93 } 94 95 struct test_params { 96 useconds_t memslot_modification_delay; 97 uint64_t nr_memslot_modifications; 98 bool partition_vcpu_memory_access; 99 }; 100 101 static void run_test(enum vm_guest_mode mode, void *arg) 102 { 103 struct test_params *p = arg; 104 pthread_t *vcpu_threads; 105 struct kvm_vm *vm; 106 int vcpu_id; 107 108 vm = perf_test_create_vm(mode, nr_vcpus, guest_percpu_mem_size, 109 VM_MEM_SRC_ANONYMOUS); 110 111 perf_test_args.wr_fract = 1; 112 113 vcpu_threads = malloc(nr_vcpus * sizeof(*vcpu_threads)); 114 TEST_ASSERT(vcpu_threads, "Memory allocation failed"); 115 116 perf_test_setup_vcpus(vm, nr_vcpus, guest_percpu_mem_size, 117 p->partition_vcpu_memory_access); 118 119 /* Export the shared variables to the guest */ 120 sync_global_to_guest(vm, perf_test_args); 121 122 pr_info("Finished creating vCPUs\n"); 123 124 for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) 125 pthread_create(&vcpu_threads[vcpu_id], NULL, vcpu_worker, 126 &perf_test_args.vcpu_args[vcpu_id]); 127 128 pr_info("Started all vCPUs\n"); 129 130 add_remove_memslot(vm, p->memslot_modification_delay, 131 p->nr_memslot_modifications); 132 133 run_vcpus = false; 134 135 /* Wait for the vcpu threads to quit */ 136 for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) 137 pthread_join(vcpu_threads[vcpu_id], NULL); 138 139 pr_info("All vCPU threads joined\n"); 140 141 ucall_uninit(vm); 142 kvm_vm_free(vm); 143 144 free(vcpu_threads); 145 } 146 147 static void help(char *name) 148 { 149 puts(""); 150 printf("usage: %s [-h] [-m mode] [-d delay_usec]\n" 151 " [-b memory] [-v vcpus] [-o] [-i iterations]\n", name); 152 guest_modes_help(); 153 printf(" -d: add a delay between each iteration of adding and\n" 154 " deleting a memslot in usec.\n"); 155 printf(" -b: specify the size of the memory region which should be\n" 156 " accessed by each vCPU. e.g. 10M or 3G.\n" 157 " Default: 1G\n"); 158 printf(" -v: specify the number of vCPUs to run.\n"); 159 printf(" -o: Overlap guest memory accesses instead of partitioning\n" 160 " them into a separate region of memory for each vCPU.\n"); 161 printf(" -i: specify the number of iterations of adding and removing\n" 162 " a memslot.\n" 163 " Default: %d\n", DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS); 164 puts(""); 165 exit(0); 166 } 167 168 int main(int argc, char *argv[]) 169 { 170 int max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS); 171 int opt; 172 struct test_params p = { 173 .memslot_modification_delay = 0, 174 .nr_memslot_modifications = 175 DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS, 176 .partition_vcpu_memory_access = true 177 }; 178 179 guest_modes_append_default(); 180 181 while ((opt = getopt(argc, argv, "hm:d:b:v:oi:")) != -1) { 182 switch (opt) { 183 case 'm': 184 guest_modes_cmdline(optarg); 185 break; 186 case 'd': 187 p.memslot_modification_delay = strtoul(optarg, NULL, 0); 188 TEST_ASSERT(p.memslot_modification_delay >= 0, 189 "A negative delay is not supported."); 190 break; 191 case 'b': 192 guest_percpu_mem_size = parse_size(optarg); 193 break; 194 case 'v': 195 nr_vcpus = atoi(optarg); 196 TEST_ASSERT(nr_vcpus > 0 && nr_vcpus <= max_vcpus, 197 "Invalid number of vcpus, must be between 1 and %d", 198 max_vcpus); 199 break; 200 case 'o': 201 p.partition_vcpu_memory_access = false; 202 break; 203 case 'i': 204 p.nr_memslot_modifications = atoi(optarg); 205 break; 206 case 'h': 207 default: 208 help(argv[0]); 209 break; 210 } 211 } 212 213 for_each_guest_mode(run_test, &p); 214 215 return 0; 216 } 217