diff options
Diffstat (limited to 'tools/testing/selftests/kvm/kvm_binary_stats_test.c')
-rw-r--r-- | tools/testing/selftests/kvm/kvm_binary_stats_test.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/kvm_binary_stats_test.c b/tools/testing/selftests/kvm/kvm_binary_stats_test.c new file mode 100644 index 0000000000..698c1cfa31 --- /dev/null +++ b/tools/testing/selftests/kvm/kvm_binary_stats_test.c @@ -0,0 +1,275 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * kvm_binary_stats_test + * + * Copyright (C) 2021, Google LLC. + * + * Test the fd-based interface for KVM statistics. + */ + +#define _GNU_SOURCE /* for program_invocation_short_name */ +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> + +#include "test_util.h" + +#include "kvm_util.h" +#include "asm/kvm.h" +#include "linux/kvm.h" +#include "kselftest.h" + +static void stats_test(int stats_fd) +{ + ssize_t ret; + int i; + size_t size_desc; + size_t size_data = 0; + struct kvm_stats_header header; + char *id; + struct kvm_stats_desc *stats_desc; + u64 *stats_data; + struct kvm_stats_desc *pdesc; + u32 type, unit, base; + + /* Read kvm stats header */ + read_stats_header(stats_fd, &header); + + size_desc = get_stats_descriptor_size(&header); + + /* Read kvm stats id string */ + id = malloc(header.name_size); + TEST_ASSERT(id, "Allocate memory for id string"); + + ret = pread(stats_fd, id, header.name_size, sizeof(header)); + TEST_ASSERT(ret == header.name_size, + "Expected header size '%u', read '%lu' bytes", + header.name_size, ret); + + /* Check id string, that should start with "kvm" */ + TEST_ASSERT(!strncmp(id, "kvm", 3) && strlen(id) < header.name_size, + "Invalid KVM stats type, id: %s", id); + + /* Sanity check for other fields in header */ + if (header.num_desc == 0) { + ksft_print_msg("No KVM stats defined!\n"); + return; + } + /* + * The descriptor and data offsets must be valid, they must not overlap + * the header, and the descriptor and data blocks must not overlap each + * other. Note, the data block is rechecked after its size is known. + */ + TEST_ASSERT(header.desc_offset && header.desc_offset >= sizeof(header) && + header.data_offset && header.data_offset >= sizeof(header), + "Invalid offset fields in header"); + + TEST_ASSERT(header.desc_offset > header.data_offset || + (header.desc_offset + size_desc * header.num_desc <= header.data_offset), + "Descriptor block is overlapped with data block"); + + /* Read kvm stats descriptors */ + stats_desc = read_stats_descriptors(stats_fd, &header); + + /* Sanity check for fields in descriptors */ + for (i = 0; i < header.num_desc; ++i) { + pdesc = get_stats_descriptor(stats_desc, i, &header); + type = pdesc->flags & KVM_STATS_TYPE_MASK; + unit = pdesc->flags & KVM_STATS_UNIT_MASK; + base = pdesc->flags & KVM_STATS_BASE_MASK; + + /* Check name string */ + TEST_ASSERT(strlen(pdesc->name) < header.name_size, + "KVM stats name (index: %d) too long", i); + + /* Check type,unit,base boundaries */ + TEST_ASSERT(type <= KVM_STATS_TYPE_MAX, + "Unknown KVM stats (%s) type: %u", pdesc->name, type); + TEST_ASSERT(unit <= KVM_STATS_UNIT_MAX, + "Unknown KVM stats (%s) unit: %u", pdesc->name, unit); + TEST_ASSERT(base <= KVM_STATS_BASE_MAX, + "Unknown KVM stats (%s) base: %u", pdesc->name, base); + + /* + * Check exponent for stats unit + * Exponent for counter should be greater than or equal to 0 + * Exponent for unit bytes should be greater than or equal to 0 + * Exponent for unit seconds should be less than or equal to 0 + * Exponent for unit clock cycles should be greater than or + * equal to 0 + * Exponent for unit boolean should be 0 + */ + switch (pdesc->flags & KVM_STATS_UNIT_MASK) { + case KVM_STATS_UNIT_NONE: + case KVM_STATS_UNIT_BYTES: + case KVM_STATS_UNIT_CYCLES: + TEST_ASSERT(pdesc->exponent >= 0, + "Unsupported KVM stats (%s) exponent: %i", + pdesc->name, pdesc->exponent); + break; + case KVM_STATS_UNIT_SECONDS: + TEST_ASSERT(pdesc->exponent <= 0, + "Unsupported KVM stats (%s) exponent: %i", + pdesc->name, pdesc->exponent); + break; + case KVM_STATS_UNIT_BOOLEAN: + TEST_ASSERT(pdesc->exponent == 0, + "Unsupported KVM stats (%s) exponent: %d", + pdesc->name, pdesc->exponent); + break; + } + + /* Check size field, which should not be zero */ + TEST_ASSERT(pdesc->size, + "KVM descriptor(%s) with size of 0", pdesc->name); + /* Check bucket_size field */ + switch (pdesc->flags & KVM_STATS_TYPE_MASK) { + case KVM_STATS_TYPE_LINEAR_HIST: + TEST_ASSERT(pdesc->bucket_size, + "Bucket size of Linear Histogram stats (%s) is zero", + pdesc->name); + break; + default: + TEST_ASSERT(!pdesc->bucket_size, + "Bucket size of stats (%s) is not zero", + pdesc->name); + } + size_data = max(size_data, pdesc->offset + pdesc->size * sizeof(*stats_data)); + } + + /* + * Now that the size of the data block is known, verify the data block + * doesn't overlap the descriptor block. + */ + TEST_ASSERT(header.data_offset >= header.desc_offset || + header.data_offset + size_data <= header.desc_offset, + "Data block is overlapped with Descriptor block"); + + /* Check validity of all stats data size */ + TEST_ASSERT(size_data >= header.num_desc * sizeof(*stats_data), + "Data size is not correct"); + + /* Allocate memory for stats data */ + stats_data = malloc(size_data); + TEST_ASSERT(stats_data, "Allocate memory for stats data"); + /* Read kvm stats data as a bulk */ + ret = pread(stats_fd, stats_data, size_data, header.data_offset); + TEST_ASSERT(ret == size_data, "Read KVM stats data"); + /* Read kvm stats data one by one */ + for (i = 0; i < header.num_desc; ++i) { + pdesc = get_stats_descriptor(stats_desc, i, &header); + read_stat_data(stats_fd, &header, pdesc, stats_data, + pdesc->size); + } + + free(stats_data); + free(stats_desc); + free(id); + + close(stats_fd); + TEST_ASSERT(fcntl(stats_fd, F_GETFD) == -1, "Stats fd not freed"); +} + +#define DEFAULT_NUM_VM 4 +#define DEFAULT_NUM_VCPU 4 + +/* + * Usage: kvm_bin_form_stats [#vm] [#vcpu] + * The first parameter #vm set the number of VMs being created. + * The second parameter #vcpu set the number of VCPUs being created. + * By default, DEFAULT_NUM_VM VM and DEFAULT_NUM_VCPU VCPU for the VM would be + * created for testing. + */ + +int main(int argc, char *argv[]) +{ + int vm_stats_fds, *vcpu_stats_fds; + int i, j; + struct kvm_vcpu **vcpus; + struct kvm_vm **vms; + int max_vm = DEFAULT_NUM_VM; + int max_vcpu = DEFAULT_NUM_VCPU; + + /* Get the number of VMs and VCPUs that would be created for testing. */ + if (argc > 1) { + max_vm = strtol(argv[1], NULL, 0); + if (max_vm <= 0) + max_vm = DEFAULT_NUM_VM; + } + if (argc > 2) { + max_vcpu = strtol(argv[2], NULL, 0); + if (max_vcpu <= 0) + max_vcpu = DEFAULT_NUM_VCPU; + } + + ksft_print_header(); + + /* Check the extension for binary stats */ + TEST_REQUIRE(kvm_has_cap(KVM_CAP_BINARY_STATS_FD)); + + ksft_set_plan(max_vm); + + /* Create VMs and VCPUs */ + vms = malloc(sizeof(vms[0]) * max_vm); + TEST_ASSERT(vms, "Allocate memory for storing VM pointers"); + + vcpus = malloc(sizeof(struct kvm_vcpu *) * max_vm * max_vcpu); + TEST_ASSERT(vcpus, "Allocate memory for storing vCPU pointers"); + + /* + * Not per-VM as the array is populated, used, and invalidated within a + * single for-loop iteration. + */ + vcpu_stats_fds = calloc(max_vm, sizeof(*vcpu_stats_fds)); + TEST_ASSERT(vcpu_stats_fds, "Allocate memory for VM stats fds"); + + for (i = 0; i < max_vm; ++i) { + vms[i] = vm_create_barebones(); + for (j = 0; j < max_vcpu; ++j) + vcpus[i * max_vcpu + j] = __vm_vcpu_add(vms[i], j); + } + + /* + * Check stats read for every VM and vCPU, with a variety of flavors. + * Note, stats_test() closes the passed in stats fd. + */ + for (i = 0; i < max_vm; ++i) { + /* + * Verify that creating multiple userspace references to a + * single stats file works and doesn't cause explosions. + */ + vm_stats_fds = vm_get_stats_fd(vms[i]); + stats_test(dup(vm_stats_fds)); + + /* Verify userspace can instantiate multiple stats files. */ + stats_test(vm_get_stats_fd(vms[i])); + + for (j = 0; j < max_vcpu; ++j) { + vcpu_stats_fds[j] = vcpu_get_stats_fd(vcpus[i * max_vcpu + j]); + stats_test(dup(vcpu_stats_fds[j])); + stats_test(vcpu_get_stats_fd(vcpus[i * max_vcpu + j])); + } + + /* + * Close the VM fd and redo the stats tests. KVM should gift a + * reference (to the VM) to each stats fd, i.e. stats should + * still be accessible even after userspace has put its last + * _direct_ reference to the VM. + */ + kvm_vm_free(vms[i]); + + stats_test(vm_stats_fds); + for (j = 0; j < max_vcpu; ++j) + stats_test(vcpu_stats_fds[j]); + + ksft_test_result_pass("vm%i\n", i); + } + + free(vms); + free(vcpus); + free(vcpu_stats_fds); + + ksft_finished(); /* Print results and exit() accordingly */ +} |