[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v5 1/3] target-i386: fallback vcpu's TSC rate to
From: |
Eduardo Habkost |
Subject: |
Re: [Qemu-devel] [PATCH v5 1/3] target-i386: fallback vcpu's TSC rate to value returned by KVM |
Date: |
Tue, 17 Nov 2015 11:14:44 -0200 |
User-agent: |
Mutt/1.5.23 (2014-03-12) |
On Tue, Nov 17, 2015 at 01:20:37PM +0800, Haozhong Zhang wrote:
> If no user-specified TSC rate is present, we will try to set
> env->tsc_khz to the value returned by KVM_GET_TSC_KHZ.
>
> Signed-off-by: Haozhong Zhang <address@hidden>
> ---
> target-i386/kvm.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index 2a9953b..9e4d27f 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -832,6 +832,18 @@ int kvm_arch_init_vcpu(CPUState *cs)
> }
> }
>
> + /*
> + * If no user-specified TSC frequency is present, we will try to
> + * set env->tsc_khz to the value used by KVM.
> + */
If you send a new version of this series, please to describe
"why", not "what". We can see in the code that we are setting
env->tsc to the value used by KVM, but the comment need to
explain why.
> + if (!env->tsc_khz) {
> + r = kvm_check_extension(cs->kvm_state, KVM_CAP_GET_TSC_KHZ) ?
> + kvm_vcpu_ioctl(cs, KVM_GET_TSC_KHZ) : -ENOTSUP;
> + if (r > 0) {
> + env->tsc_khz = r;
> + }
> + }
> +
> if (has_xsave) {
> env->kvm_xsave_buf = qemu_memalign(4096, sizeof(struct kvm_xsave));
> }
> --
> 2.4.8
>
--
Eduardo