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 #include <stdio.h> 10 #include <stdlib.h> 11 #include <sys/syscall.h> 12 #include <unistd.h> 13 #include <asm/unistd.h> 14 #include <time.h> 15 #include <poll.h> 16 #include <pthread.h> 17 #include <linux/bitmap.h> 18 #include <linux/bitops.h> 19 #include <linux/userfaultfd.h> 20 21 #include "memstress.h" 22 #include "processor.h" 23 #include "test_util.h" 24 #include "guest_modes.h" 25 #include "ucall_common.h" 26 27 #define DUMMY_MEMSLOT_INDEX 7 28 29 #define DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS 10 30 31 32 static int nr_vcpus = 1; 33 static uint64_t guest_percpu_mem_size = DEFAULT_PER_VCPU_MEM_SIZE; 34 35 static void vcpu_worker(struct memstress_vcpu_args *vcpu_args) 36 { 37 struct kvm_vcpu *vcpu = vcpu_args->vcpu; 38 struct kvm_run *run; 39 int ret; 40 41 run = vcpu->run; 42 43 /* Let the guest access its memory until a stop signal is received */ 44 while (!READ_ONCE(memstress_args.stop_vcpus)) { 45 ret = _vcpu_run(vcpu); 46 TEST_ASSERT(ret == 0, "vcpu_run failed: %d", ret); 47 48 if (get_ucall(vcpu, NULL) == UCALL_SYNC) 49 continue; 50 51 TEST_ASSERT(false, 52 "Invalid guest sync status: exit_reason=%s\n", 53 exit_reason_str(run->exit_reason)); 54 } 55 } 56 57 static void add_remove_memslot(struct kvm_vm *vm, useconds_t delay, 58 uint64_t nr_modifications) 59 { 60 uint64_t pages = max_t(int, vm->page_size, getpagesize()) / vm->page_size; 61 uint64_t gpa; 62 int i; 63 64 /* 65 * Add the dummy memslot just below the memstress memslot, which is 66 * at the top of the guest physical address space. 67 */ 68 gpa = memstress_args.gpa - pages * vm->page_size; 69 70 for (i = 0; i < nr_modifications; i++) { 71 usleep(delay); 72 vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, gpa, 73 DUMMY_MEMSLOT_INDEX, pages, 0); 74 75 vm_mem_region_delete(vm, DUMMY_MEMSLOT_INDEX); 76 } 77 } 78 79 struct test_params { 80 useconds_t delay; 81 uint64_t nr_iterations; 82 bool partition_vcpu_memory_access; 83 bool disable_slot_zap_quirk; 84 }; 85 86 static void run_test(enum vm_guest_mode mode, void *arg) 87 { 88 struct test_params *p = arg; 89 struct kvm_vm *vm; 90 91 vm = memstress_create_vm(mode, nr_vcpus, guest_percpu_mem_size, 1, 92 VM_MEM_SRC_ANONYMOUS, 93 p->partition_vcpu_memory_access); 94 #ifdef __x86_64__ 95 if (p->disable_slot_zap_quirk) 96 vm_enable_cap(vm, KVM_CAP_DISABLE_QUIRKS2, KVM_X86_QUIRK_SLOT_ZAP_ALL); 97 98 pr_info("Memslot zap quirk %s\n", p->disable_slot_zap_quirk ? 99 "disabled" : "enabled"); 100 #endif 101 102 pr_info("Finished creating vCPUs\n"); 103 104 memstress_start_vcpu_threads(nr_vcpus, vcpu_worker); 105 106 pr_info("Started all vCPUs\n"); 107 108 add_remove_memslot(vm, p->delay, p->nr_iterations); 109 110 memstress_join_vcpu_threads(nr_vcpus); 111 pr_info("All vCPU threads joined\n"); 112 113 memstress_destroy_vm(vm); 114 } 115 116 static void help(char *name) 117 { 118 puts(""); 119 printf("usage: %s [-h] [-m mode] [-d delay_usec] [-q]\n" 120 " [-b memory] [-v vcpus] [-o] [-i iterations]\n", name); 121 guest_modes_help(); 122 printf(" -d: add a delay between each iteration of adding and\n" 123 " deleting a memslot in usec.\n"); 124 printf(" -q: Disable memslot zap quirk.\n"); 125 printf(" -b: specify the size of the memory region which should be\n" 126 " accessed by each vCPU. e.g. 10M or 3G.\n" 127 " Default: 1G\n"); 128 printf(" -v: specify the number of vCPUs to run.\n"); 129 printf(" -o: Overlap guest memory accesses instead of partitioning\n" 130 " them into a separate region of memory for each vCPU.\n"); 131 printf(" -i: specify the number of iterations of adding and removing\n" 132 " a memslot.\n" 133 " Default: %d\n", DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS); 134 puts(""); 135 exit(0); 136 } 137 138 int main(int argc, char *argv[]) 139 { 140 int max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS); 141 int opt; 142 struct test_params p = { 143 .delay = 0, 144 .nr_iterations = DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS, 145 .partition_vcpu_memory_access = true 146 }; 147 148 guest_modes_append_default(); 149 150 while ((opt = getopt(argc, argv, "hm:d:qb:v:oi:")) != -1) { 151 switch (opt) { 152 case 'm': 153 guest_modes_cmdline(optarg); 154 break; 155 case 'd': 156 p.delay = atoi_non_negative("Delay", optarg); 157 break; 158 case 'b': 159 guest_percpu_mem_size = parse_size(optarg); 160 break; 161 case 'v': 162 nr_vcpus = atoi_positive("Number of vCPUs", optarg); 163 TEST_ASSERT(nr_vcpus <= max_vcpus, 164 "Invalid number of vcpus, must be between 1 and %d", 165 max_vcpus); 166 break; 167 case 'o': 168 p.partition_vcpu_memory_access = false; 169 break; 170 case 'i': 171 p.nr_iterations = atoi_positive("Number of iterations", optarg); 172 break; 173 #ifdef __x86_64__ 174 case 'q': 175 p.disable_slot_zap_quirk = true; 176 177 TEST_REQUIRE(kvm_check_cap(KVM_CAP_DISABLE_QUIRKS2) & 178 KVM_X86_QUIRK_SLOT_ZAP_ALL); 179 break; 180 #endif 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