Re: [PATCH v8 2/4] selftests: KVM: Add fpu and one reg set/get library functions

Andrew Jones
2020-01-30T15:04:49Z

On Thu, Jan 30, 2020 at 03:58:46PM +0100, Janosch Frank wrote:
> On 1/30/20 3:30 PM, Andrew Jones wrote:
> > On Thu, Jan 30, 2020 at 03:10:55PM +0100, Janosch Frank wrote:
> >> On 1/30/20 2:55 PM, Andrew Jones wrote:
> >>> On Thu, Jan 30, 2020 at 11:36:21AM +0100, Thomas Huth wrote:
> >>>> On 29/01/2020 21.03, Janosch Frank wrote:
> >>>>> Add library access to more registers.
> >>>>>
> >>>>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> >>>>> ---
> >>>>> .../testing/selftests/kvm/include/kvm_util.h | 6 +++
> >>>>> tools/testing/selftests/kvm/lib/kvm_util.c | 48 +++++++++++++++++++
> >>>>> 2 files changed, 54 insertions(+)
> >>>>>
> >>>>> diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
> >>>>> index 29cccaf96baf..ae0d14c2540a 100644
> >>>>> --- a/tools/testing/selftests/kvm/include/kvm_util.h
> >>>>> +++ b/tools/testing/selftests/kvm/include/kvm_util.h
> >>>>> @@ -125,6 +125,12 @@ void vcpu_sregs_set(struct kvm_vm *vm, uint32_t vcpuid,
> >>>>> struct kvm_sregs *sregs);
> >>>>> int _vcpu_sregs_set(struct kvm_vm *vm, uint32_t vcpuid,
> >>>>> struct kvm_sregs *sregs);
> >>>>> +void vcpu_fpu_get(struct kvm_vm *vm, uint32_t vcpuid,
> >>>>> + struct kvm_fpu *fpu);
> >>>>> +void vcpu_fpu_set(struct kvm_vm *vm, uint32_t vcpuid,
> >>>>> + struct kvm_fpu *fpu);
> >
> > nit: no need for the above line breaks. We don't even get to 80 char.
> >
> >>>>> +void vcpu_get_reg(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_one_reg *reg);
> >>>>> +void vcpu_set_reg(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_one_reg *reg);
> >>>>> #ifdef __KVM_HAVE_VCPU_EVENTS
> >>>>> void vcpu_events_get(struct kvm_vm *vm, uint32_t vcpuid,
> >>>>> struct kvm_vcpu_events *events);
> >>>>> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> >>>>> index 41cf45416060..dae117728ec6 100644
> >>>>> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> >>>>> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> >>>>> @@ -1373,6 +1373,54 @@ int _vcpu_sregs_set(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
> >>>>> return ioctl(vcpu->fd, KVM_SET_SREGS, sregs);
> >>>>> }
> >>>>>
> >>>>> +void vcpu_fpu_get(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_fpu *fpu)
> >>>>> +{
> >>>>> + struct vcpu *vcpu = vcpu_find(vm, vcpuid);
> >>>>> + int ret;
> >>>>> +
> >>>>> + TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);
> >>>>> +
> >>>>> + ret = ioctl(vcpu->fd, KVM_GET_FPU, fpu);
> >>>>> + TEST_ASSERT(ret == 0, "KVM_GET_FPU failed, rc: %i errno: %i",
> >>>>> + ret, errno);
> >>>>> +}
> >>>>> +
> >>>>> +void vcpu_fpu_set(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_fpu *fpu)
> >>>>> +{
> >>>>> + struct vcpu *vcpu = vcpu_find(vm, vcpuid);
> >>>>> + int ret;
> >>>>> +
> >>>>> + TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);
> >>>>> +
> >>>>> + ret = ioctl(vcpu->fd, KVM_SET_FPU, fpu);
> >>>>> + TEST_ASSERT(ret == 0, "KVM_SET_FPU failed, rc: %i errno: %i",
> >>>>> + ret, errno);
> >>>>> +}
> >>>>> +
> >>>>> +void vcpu_get_reg(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_one_reg *reg)
> >>>>> +{
> >>>>> + struct vcpu *vcpu = vcpu_find(vm, vcpuid);
> >>>>> + int ret;
> >>>>> +
> >>>>> + TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);
> >>>>> +
> >>>>> + ret = ioctl(vcpu->fd, KVM_GET_ONE_REG, reg);
> >>>>> + TEST_ASSERT(ret == 0, "KVM_GET_ONE_REG failed, rc: %i errno: %i",
> >>>>> + ret, errno);
> >>>>> +}
> >>>>> +
> >>>>> +void vcpu_set_reg(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_one_reg *reg)
> >>>>> +{
> >>>>> + struct vcpu *vcpu = vcpu_find(vm, vcpuid);
> >>>>> + int ret;
> >>>>> +
> >>>>> + TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);
> >>>>> +
> >>>>> + ret = ioctl(vcpu->fd, KVM_SET_ONE_REG, reg);
> >>>>> + TEST_ASSERT(ret == 0, "KVM_SET_ONE_REG failed, rc: %i errno: %i",
> >>>>> + ret, errno);
> >>>>> +}
> >>>>> +
> >>>>> /*
> >>>>> * VCPU Ioctl
> >>>>> *
> >>>>>
> >>>>
> >>>> Reviewed-by: Thomas Huth <thuth@redhat.com>
> >>>>
> >>>
> >>> How about what's below instead. It should be equivalent.
> >>
> >> With your proposed changes we loose a bit verbosity in the error
> >> messages. I need to think about which I like more.
> >
> > Looks like both error messages are missing something. The ones above are
> > missing the string version of errno. The ones below are missing the string
> > version of cmd. It's easy to add the string version of errno, which is
> > an argument for keeping the functions above (but we could at least use
> > _vcpu_ioctl to avoid duplicating the vcpu_find and vcpu!=NULL assert).
>
> Will do
>
> > Or, we could consider adding a kvm_ioctl_cmd_to_string() function,
> > which might be nice for other ioctl wrappers now and in the future.
> > It shouldn't be too bad to generate a string table from kvm.h, but of
> > course we'd have to keep it maintained.
>
> I'm currently occupied with managing a lot of patches, so something like
> that is not very high on my todo list.

Yeah, no worries. We can go with a patch like this for now. I'll
experiment with a table generator when I get a chance in order to
see how ugly it gets. If it's too ugly I'll drop it too.

Thanks,
drew