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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * kvm_binary_stats_test4 *5 * Copyright (C) 2021, Google LLC.6 *7 * Test the fd-based interface for KVM statistics.8 */9#include <fcntl.h>10#include <stdio.h>11#include <stdlib.h>12#include <string.h>13#include <errno.h>14 15#include "test_util.h"16 17#include "kvm_util.h"18#include "asm/kvm.h"19#include "linux/kvm.h"20#include "kselftest.h"21 22static void stats_test(int stats_fd)23{24 ssize_t ret;25 int i;26 size_t size_desc;27 size_t size_data = 0;28 struct kvm_stats_header header;29 char *id;30 struct kvm_stats_desc *stats_desc;31 u64 *stats_data;32 struct kvm_stats_desc *pdesc;33 u32 type, unit, base;34 35 /* Read kvm stats header */36 read_stats_header(stats_fd, &header);37 38 size_desc = get_stats_descriptor_size(&header);39 40 /* Read kvm stats id string */41 id = malloc(header.name_size);42 TEST_ASSERT(id, "Allocate memory for id string");43 44 ret = pread(stats_fd, id, header.name_size, sizeof(header));45 TEST_ASSERT(ret == header.name_size,46 "Expected header size '%u', read '%lu' bytes",47 header.name_size, ret);48 49 /* Check id string, that should start with "kvm" */50 TEST_ASSERT(!strncmp(id, "kvm", 3) && strlen(id) < header.name_size,51 "Invalid KVM stats type, id: %s", id);52 53 /* Sanity check for other fields in header */54 if (header.num_desc == 0) {55 ksft_print_msg("No KVM stats defined!\n");56 return;57 }58 /*59 * The descriptor and data offsets must be valid, they must not overlap60 * the header, and the descriptor and data blocks must not overlap each61 * other. Note, the data block is rechecked after its size is known.62 */63 TEST_ASSERT(header.desc_offset && header.desc_offset >= sizeof(header) &&64 header.data_offset && header.data_offset >= sizeof(header),65 "Invalid offset fields in header");66 67 TEST_ASSERT(header.desc_offset > header.data_offset ||68 (header.desc_offset + size_desc * header.num_desc <= header.data_offset),69 "Descriptor block is overlapped with data block");70 71 /* Read kvm stats descriptors */72 stats_desc = read_stats_descriptors(stats_fd, &header);73 74 /* Sanity check for fields in descriptors */75 for (i = 0; i < header.num_desc; ++i) {76 pdesc = get_stats_descriptor(stats_desc, i, &header);77 type = pdesc->flags & KVM_STATS_TYPE_MASK;78 unit = pdesc->flags & KVM_STATS_UNIT_MASK;79 base = pdesc->flags & KVM_STATS_BASE_MASK;80 81 /* Check name string */82 TEST_ASSERT(strlen(pdesc->name) < header.name_size,83 "KVM stats name (index: %d) too long", i);84 85 /* Check type,unit,base boundaries */86 TEST_ASSERT(type <= KVM_STATS_TYPE_MAX,87 "Unknown KVM stats (%s) type: %u", pdesc->name, type);88 TEST_ASSERT(unit <= KVM_STATS_UNIT_MAX,89 "Unknown KVM stats (%s) unit: %u", pdesc->name, unit);90 TEST_ASSERT(base <= KVM_STATS_BASE_MAX,91 "Unknown KVM stats (%s) base: %u", pdesc->name, base);92 93 /*94 * Check exponent for stats unit95 * Exponent for counter should be greater than or equal to 096 * Exponent for unit bytes should be greater than or equal to 097 * Exponent for unit seconds should be less than or equal to 098 * Exponent for unit clock cycles should be greater than or99 * equal to 0100 * Exponent for unit boolean should be 0101 */102 switch (pdesc->flags & KVM_STATS_UNIT_MASK) {103 case KVM_STATS_UNIT_NONE:104 case KVM_STATS_UNIT_BYTES:105 case KVM_STATS_UNIT_CYCLES:106 TEST_ASSERT(pdesc->exponent >= 0,107 "Unsupported KVM stats (%s) exponent: %i",108 pdesc->name, pdesc->exponent);109 break;110 case KVM_STATS_UNIT_SECONDS:111 TEST_ASSERT(pdesc->exponent <= 0,112 "Unsupported KVM stats (%s) exponent: %i",113 pdesc->name, pdesc->exponent);114 break;115 case KVM_STATS_UNIT_BOOLEAN:116 TEST_ASSERT(pdesc->exponent == 0,117 "Unsupported KVM stats (%s) exponent: %d",118 pdesc->name, pdesc->exponent);119 break;120 }121 122 /* Check size field, which should not be zero */123 TEST_ASSERT(pdesc->size,124 "KVM descriptor(%s) with size of 0", pdesc->name);125 /* Check bucket_size field */126 switch (pdesc->flags & KVM_STATS_TYPE_MASK) {127 case KVM_STATS_TYPE_LINEAR_HIST:128 TEST_ASSERT(pdesc->bucket_size,129 "Bucket size of Linear Histogram stats (%s) is zero",130 pdesc->name);131 break;132 default:133 TEST_ASSERT(!pdesc->bucket_size,134 "Bucket size of stats (%s) is not zero",135 pdesc->name);136 }137 size_data = max(size_data, pdesc->offset + pdesc->size * sizeof(*stats_data));138 }139 140 /*141 * Now that the size of the data block is known, verify the data block142 * doesn't overlap the descriptor block.143 */144 TEST_ASSERT(header.data_offset >= header.desc_offset ||145 header.data_offset + size_data <= header.desc_offset,146 "Data block is overlapped with Descriptor block");147 148 /* Check validity of all stats data size */149 TEST_ASSERT(size_data >= header.num_desc * sizeof(*stats_data),150 "Data size is not correct");151 152 /* Allocate memory for stats data */153 stats_data = malloc(size_data);154 TEST_ASSERT(stats_data, "Allocate memory for stats data");155 /* Read kvm stats data as a bulk */156 ret = pread(stats_fd, stats_data, size_data, header.data_offset);157 TEST_ASSERT(ret == size_data, "Read KVM stats data");158 /* Read kvm stats data one by one */159 for (i = 0; i < header.num_desc; ++i) {160 pdesc = get_stats_descriptor(stats_desc, i, &header);161 read_stat_data(stats_fd, &header, pdesc, stats_data,162 pdesc->size);163 }164 165 free(stats_data);166 free(stats_desc);167 free(id);168 169 close(stats_fd);170 TEST_ASSERT(fcntl(stats_fd, F_GETFD) == -1, "Stats fd not freed");171}172 173#define DEFAULT_NUM_VM 4174#define DEFAULT_NUM_VCPU 4175 176/*177 * Usage: kvm_bin_form_stats [#vm] [#vcpu]178 * The first parameter #vm set the number of VMs being created.179 * The second parameter #vcpu set the number of VCPUs being created.180 * By default, DEFAULT_NUM_VM VM and DEFAULT_NUM_VCPU VCPU for the VM would be181 * created for testing.182 */183 184int main(int argc, char *argv[])185{186 int vm_stats_fds, *vcpu_stats_fds;187 int i, j;188 struct kvm_vcpu **vcpus;189 struct kvm_vm **vms;190 int max_vm = DEFAULT_NUM_VM;191 int max_vcpu = DEFAULT_NUM_VCPU;192 193 /* Get the number of VMs and VCPUs that would be created for testing. */194 if (argc > 1) {195 max_vm = strtol(argv[1], NULL, 0);196 if (max_vm <= 0)197 max_vm = DEFAULT_NUM_VM;198 }199 if (argc > 2) {200 max_vcpu = strtol(argv[2], NULL, 0);201 if (max_vcpu <= 0)202 max_vcpu = DEFAULT_NUM_VCPU;203 }204 205 ksft_print_header();206 207 /* Check the extension for binary stats */208 TEST_REQUIRE(kvm_has_cap(KVM_CAP_BINARY_STATS_FD));209 210 ksft_set_plan(max_vm);211 212 /* Create VMs and VCPUs */213 vms = malloc(sizeof(vms[0]) * max_vm);214 TEST_ASSERT(vms, "Allocate memory for storing VM pointers");215 216 vcpus = malloc(sizeof(struct kvm_vcpu *) * max_vm * max_vcpu);217 TEST_ASSERT(vcpus, "Allocate memory for storing vCPU pointers");218 219 /*220 * Not per-VM as the array is populated, used, and invalidated within a221 * single for-loop iteration.222 */223 vcpu_stats_fds = calloc(max_vm, sizeof(*vcpu_stats_fds));224 TEST_ASSERT(vcpu_stats_fds, "Allocate memory for VM stats fds");225 226 for (i = 0; i < max_vm; ++i) {227 vms[i] = vm_create_barebones();228 for (j = 0; j < max_vcpu; ++j)229 vcpus[i * max_vcpu + j] = __vm_vcpu_add(vms[i], j);230 }231 232 /*233 * Check stats read for every VM and vCPU, with a variety of flavors.234 * Note, stats_test() closes the passed in stats fd.235 */236 for (i = 0; i < max_vm; ++i) {237 /*238 * Verify that creating multiple userspace references to a239 * single stats file works and doesn't cause explosions.240 */241 vm_stats_fds = vm_get_stats_fd(vms[i]);242 stats_test(dup(vm_stats_fds));243 244 /* Verify userspace can instantiate multiple stats files. */245 stats_test(vm_get_stats_fd(vms[i]));246 247 for (j = 0; j < max_vcpu; ++j) {248 vcpu_stats_fds[j] = vcpu_get_stats_fd(vcpus[i * max_vcpu + j]);249 stats_test(dup(vcpu_stats_fds[j]));250 stats_test(vcpu_get_stats_fd(vcpus[i * max_vcpu + j]));251 }252 253 /*254 * Close the VM fd and redo the stats tests. KVM should gift a255 * reference (to the VM) to each stats fd, i.e. stats should256 * still be accessible even after userspace has put its last257 * _direct_ reference to the VM.258 */259 kvm_vm_free(vms[i]);260 261 stats_test(vm_stats_fds);262 for (j = 0; j < max_vcpu; ++j)263 stats_test(vcpu_stats_fds[j]);264 265 ksft_test_result_pass("vm%i\n", i);266 }267 268 free(vms);269 free(vcpus);270 free(vcpu_stats_fds);271 272 ksft_finished(); /* Print results and exit() accordingly */273}274