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(struct perf_test_vcpu_args *vcpu_args) 40 { 41 int ret; 42 int vcpu_id = vcpu_args->vcpu_id; 43 struct kvm_vm *vm = perf_test_args.vm; 44 struct kvm_run *run; 45 46 run = vcpu_state(vm, vcpu_id); 47 48 /* Let the guest access its memory until a stop signal is received */ 49 while (READ_ONCE(run_vcpus)) { 50 ret = _vcpu_run(vm, vcpu_id); 51 TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret); 52 53 if (get_ucall(vm, vcpu_id, NULL) == UCALL_SYNC) 54 continue; 55 56 TEST_ASSERT(false, 57 "Invalid guest sync status: exit_reason=%s\n", 58 exit_reason_str(run->exit_reason)); 59 } 60 } 61 62 struct memslot_antagonist_args { 63 struct kvm_vm *vm; 64 useconds_t delay; 65 uint64_t nr_modifications; 66 }; 67 68 static void add_remove_memslot(struct kvm_vm *vm, useconds_t delay, 69 uint64_t nr_modifications) 70 { 71 const uint64_t pages = 1; 72 uint64_t gpa; 73 int i; 74 75 /* 76 * Add the dummy memslot just below the perf_test_util memslot, which is 77 * at the top of the guest physical address space. 78 */ 79 gpa = perf_test_args.gpa - pages * vm_get_page_size(vm); 80 81 for (i = 0; i < nr_modifications; i++) { 82 usleep(delay); 83 vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, gpa, 84 DUMMY_MEMSLOT_INDEX, pages, 0); 85 86 vm_mem_region_delete(vm, DUMMY_MEMSLOT_INDEX); 87 } 88 } 89 90 struct test_params { 91 useconds_t memslot_modification_delay; 92 uint64_t nr_memslot_modifications; 93 bool partition_vcpu_memory_access; 94 }; 95 96 static void run_test(enum vm_guest_mode mode, void *arg) 97 { 98 struct test_params *p = arg; 99 struct kvm_vm *vm; 100 101 vm = perf_test_create_vm(mode, nr_vcpus, guest_percpu_mem_size, 1, 102 VM_MEM_SRC_ANONYMOUS, 103 p->partition_vcpu_memory_access); 104 105 pr_info("Finished creating vCPUs\n"); 106 107 perf_test_start_vcpu_threads(nr_vcpus, vcpu_worker); 108 109 pr_info("Started all vCPUs\n"); 110 111 add_remove_memslot(vm, p->memslot_modification_delay, 112 p->nr_memslot_modifications); 113 114 run_vcpus = false; 115 116 perf_test_join_vcpu_threads(nr_vcpus); 117 pr_info("All vCPU threads joined\n"); 118 119 perf_test_destroy_vm(vm); 120 } 121 122 static void help(char *name) 123 { 124 puts(""); 125 printf("usage: %s [-h] [-m mode] [-d delay_usec]\n" 126 " [-b memory] [-v vcpus] [-o] [-i iterations]\n", name); 127 guest_modes_help(); 128 printf(" -d: add a delay between each iteration of adding and\n" 129 " deleting a memslot in usec.\n"); 130 printf(" -b: specify the size of the memory region which should be\n" 131 " accessed by each vCPU. e.g. 10M or 3G.\n" 132 " Default: 1G\n"); 133 printf(" -v: specify the number of vCPUs to run.\n"); 134 printf(" -o: Overlap guest memory accesses instead of partitioning\n" 135 " them into a separate region of memory for each vCPU.\n"); 136 printf(" -i: specify the number of iterations of adding and removing\n" 137 " a memslot.\n" 138 " Default: %d\n", DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS); 139 puts(""); 140 exit(0); 141 } 142 143 int main(int argc, char *argv[]) 144 { 145 int max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS); 146 int opt; 147 struct test_params p = { 148 .memslot_modification_delay = 0, 149 .nr_memslot_modifications = 150 DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS, 151 .partition_vcpu_memory_access = true 152 }; 153 154 guest_modes_append_default(); 155 156 while ((opt = getopt(argc, argv, "hm:d:b:v:oi:")) != -1) { 157 switch (opt) { 158 case 'm': 159 guest_modes_cmdline(optarg); 160 break; 161 case 'd': 162 p.memslot_modification_delay = strtoul(optarg, NULL, 0); 163 TEST_ASSERT(p.memslot_modification_delay >= 0, 164 "A negative delay is not supported."); 165 break; 166 case 'b': 167 guest_percpu_mem_size = parse_size(optarg); 168 break; 169 case 'v': 170 nr_vcpus = atoi(optarg); 171 TEST_ASSERT(nr_vcpus > 0 && nr_vcpus <= max_vcpus, 172 "Invalid number of vcpus, must be between 1 and %d", 173 max_vcpus); 174 break; 175 case 'o': 176 p.partition_vcpu_memory_access = false; 177 break; 178 case 'i': 179 p.nr_memslot_modifications = atoi(optarg); 180 break; 181 case 'h': 182 default: 183 help(argv[0]); 184 break; 185 } 186 } 187 188 for_each_guest_mode(run_test, &p); 189 190 return 0; 191 } 192