LXR linux/tools/testing/selftests/kvm/kvm_create_max

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * kvm_create_max_vcpus
   4 *
   5 * Copyright (C) 2019, Google LLC.
   6 *
   7 * Test for KVM_CAP_MAX_VCPUS and KVM_CAP_MAX_VCPU_ID.
   8 */
   9
  10#define _GNU_SOURCE /* for program_invocation_short_name */
  11#include <fcntl.h>
  12#include <stdio.h>
  13#include <stdlib.h>
  14#include <string.h>
  15
  16#include "test_util.h"
  17
  18#include "kvm_util.h"
  19#include "asm/kvm.h"
  20#include "linux/kvm.h"
  21
  22void test_vcpu_creation(int first_vcpu_id, int num_vcpus)
  23{
  24        struct kvm_vm *vm;
  25        int i;
  26
  27        pr_info("Testing creating %d vCPUs, with IDs %d...%d.\n",
  28                num_vcpus, first_vcpu_id, first_vcpu_id + num_vcpus - 1);
  29
  30        vm = vm_create(VM_MODE_DEFAULT, DEFAULT_GUEST_PHY_PAGES, O_RDWR);
  31
  32        for (i = first_vcpu_id; i < first_vcpu_id + num_vcpus; i++)
  33                /* This asserts that the vCPU was created. */
  34                vm_vcpu_add(vm, i);
  35
  36        kvm_vm_free(vm);
  37}
  38
  39int main(int argc, char *argv[])
  40{
  41        int kvm_max_vcpu_id = kvm_check_cap(KVM_CAP_MAX_VCPU_ID);
  42        int kvm_max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS);
  43
  44        pr_info("KVM_CAP_MAX_VCPU_ID: %d\n", kvm_max_vcpu_id);
  45        pr_info("KVM_CAP_MAX_VCPUS: %d\n", kvm_max_vcpus);
  46
  47        /*
  48         * Upstream KVM prior to 4.8 does not support KVM_CAP_MAX_VCPU_ID.
  49         * Userspace is supposed to use KVM_CAP_MAX_VCPUS as the maximum ID
  50         * in this case.
  51         */
  52        if (!kvm_max_vcpu_id)
  53                kvm_max_vcpu_id = kvm_max_vcpus;
  54
  55        TEST_ASSERT(kvm_max_vcpu_id >= kvm_max_vcpus,
  56                    "KVM_MAX_VCPU_ID (%d) must be at least as large as KVM_MAX_VCPUS (%d).",
  57                    kvm_max_vcpu_id, kvm_max_vcpus);
  58
  59        test_vcpu_creation(0, kvm_max_vcpus);
  60
  61        if (kvm_max_vcpu_id > kvm_max_vcpus)
  62                test_vcpu_creation(
  63                        kvm_max_vcpu_id - kvm_max_vcpus, kvm_max_vcpus);
  64
  65        return 0;
  66}
  67