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