Re: [PATCH v10 1/3] KVM: selftests: aarch64: Add helper function for the vpmu vcpu creation

[Raghavendra Rao Ananta <rananta@google.com>]

Hi Shaoqin

On Wed, Jun 19, 2024 at 1:32 AM Shaoqin Huang <shahuang@redhat.com> wrote:
>
> Create a vcpu with vpmu would be a common requirement for the vpmu test,
> so add the helper function for the vpmu vcpu creation. And use those
> helper function in the vpmu_counter_access.c test.
>
> Use this chance to delete the meaningless ASSERT about the pmuver,
> because KVM does not advertise an IMP_DEF PMU to guests.
>
> No functional changes intended.
>
> Reviewed-by: Eric Auger <eric.auger@redhat.com>
> Signed-off-by: Shaoqin Huang <shahuang@redhat.com>
> ---
>  .../kvm/aarch64/vpmu_counter_access.c         | 32 ++++---------------
>  .../selftests/kvm/include/aarch64/vpmu.h      | 28 ++++++++++++++++
>  2 files changed, 34 insertions(+), 26 deletions(-)
>  create mode 100644 tools/testing/selftests/kvm/include/aarch64/vpmu.h
>
> diff --git a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c b/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c
> index d31b9f64ba14..68da44198719 100644
> --- a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c
> +++ b/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c
> @@ -16,6 +16,7 @@
>  #include <processor.h>
>  #include <test_util.h>
>  #include <vgic.h>
> +#include <vpmu.h>
>  #include <perf/arm_pmuv3.h>
>  #include <linux/bitfield.h>
>
> @@ -407,18 +408,8 @@ static void guest_code(uint64_t expected_pmcr_n)
>  /* Create a VM that has one vCPU with PMUv3 configured. */
>  static void create_vpmu_vm(void *guest_code)
>  {
> -       struct kvm_vcpu_init init;
> -       uint8_t pmuver, ec;
> -       uint64_t dfr0, irq = 23;
> -       struct kvm_device_attr irq_attr = {
> -               .group = KVM_ARM_VCPU_PMU_V3_CTRL,
> -               .attr = KVM_ARM_VCPU_PMU_V3_IRQ,
> -               .addr = (uint64_t)&irq,
> -       };
> -       struct kvm_device_attr init_attr = {
> -               .group = KVM_ARM_VCPU_PMU_V3_CTRL,
> -               .attr = KVM_ARM_VCPU_PMU_V3_INIT,
> -       };
> +       uint8_t ec;
> +       uint64_t irq = 23;
>
>         /* The test creates the vpmu_vm multiple times. Ensure a clean state */
>         memset(&vpmu_vm, 0, sizeof(vpmu_vm));
> @@ -430,26 +421,15 @@ static void create_vpmu_vm(void *guest_code)
>                                         guest_sync_handler);
>         }
>
> -       /* Create vCPU with PMUv3 */
> -       vm_ioctl(vpmu_vm.vm, KVM_ARM_PREFERRED_TARGET, &init);
> -       init.features[0] |= (1 << KVM_ARM_VCPU_PMU_V3);
> -       vpmu_vm.vcpu = aarch64_vcpu_add(vpmu_vm.vm, 0, &init, guest_code);
> +       vpmu_vm.vcpu = vm_vcpu_add_with_vpmu(vpmu_vm.vm, 0, guest_code);
>         vcpu_init_descriptor_tables(vpmu_vm.vcpu);
>         vpmu_vm.gic_fd = vgic_v3_setup(vpmu_vm.vm, 1, 64);
>         __TEST_REQUIRE(vpmu_vm.gic_fd >= 0,
>                        "Failed to create vgic-v3, skipping");
>
> -       /* Make sure that PMUv3 support is indicated in the ID register */
> -       vcpu_get_reg(vpmu_vm.vcpu,
> -                    KVM_ARM64_SYS_REG(SYS_ID_AA64DFR0_EL1), &dfr0);
> -       pmuver = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), dfr0);
> -       TEST_ASSERT(pmuver != ID_AA64DFR0_EL1_PMUVer_IMP_DEF &&
> -                   pmuver >= ID_AA64DFR0_EL1_PMUVer_IMP,
> -                   "Unexpected PMUVER (0x%x) on the vCPU with PMUv3", pmuver);
> -
>         /* Initialize vPMU */
> -       vcpu_ioctl(vpmu_vm.vcpu, KVM_SET_DEVICE_ATTR, &irq_attr);
> -       vcpu_ioctl(vpmu_vm.vcpu, KVM_SET_DEVICE_ATTR, &init_attr);
> +       vpmu_set_irq(vpmu_vm.vcpu, irq);
> +       vpmu_init(vpmu_vm.vcpu);
>  }
>
>  static void destroy_vpmu_vm(void)
> diff --git a/tools/testing/selftests/kvm/include/aarch64/vpmu.h b/tools/testing/selftests/kvm/include/aarch64/vpmu.h
> new file mode 100644
> index 000000000000..5ef6cb011e41
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/include/aarch64/vpmu.h
> @@ -0,0 +1,28 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +#include <kvm_util.h>
> +
> +static inline struct kvm_vcpu *vm_vcpu_add_with_vpmu(struct kvm_vm *vm,
> +                                                    uint32_t vcpu_id,
> +                                                    void *guest_code)
> +{
> +       struct kvm_vcpu_init init;
> +
> +       /* Create vCPU with PMUv3 */
> +       vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init);
> +       init.features[0] |= (1 << KVM_ARM_VCPU_PMU_V3);
> +
> +       return aarch64_vcpu_add(vm, 0, &init, guest_code);
> +}
> +
> +static void vpmu_set_irq(struct kvm_vcpu *vcpu, int irq)
> +{
> +       kvm_device_attr_set(vcpu->fd, KVM_ARM_VCPU_PMU_V3_CTRL,
> +                           KVM_ARM_VCPU_PMU_V3_IRQ, &irq);
> +}
> +
> +static void vpmu_init(struct kvm_vcpu *vcpu)
> +{
> +       kvm_device_attr_set(vcpu->fd, KVM_ARM_VCPU_PMU_V3_CTRL,
> +                           KVM_ARM_VCPU_PMU_V3_INIT, NULL);
> +}
> --
> 2.40.1
>
>
Reviewed-by: Raghavendra Rao Ananta <rananta@google.com>

- Raghavendra