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