| Message ID | 20090827120730.GN30093@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Aug 27, 2009 at 03:07:30PM +0300, Gleb Natapov wrote: > No need to call it before each kvm_(set|get)_msr_common() > > Signed-off-by: Gleb Natapov <gleb@redhat.com> > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index 6b57eed..7494ef1 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -1005,9 +1005,9 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata) > data = vmcs_readl(GUEST_SYSENTER_ESP); > break; > default: > - vmx_load_host_state(to_vmx(vcpu)); > msr = find_msr_entry(to_vmx(vcpu), msr_index); > if (msr) { > + vmx_load_host_state(to_vmx(vcpu)); > data = msr->data; > break; > } > @@ -1064,9 +1064,9 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data) > } > /* Otherwise falls through to kvm_set_msr_common */ > default: > - vmx_load_host_state(vmx); > msr = find_msr_entry(vmx, msr_index); > if (msr) { > + vmx_load_host_state(vmx); All is needed here save_msrs(vmx->guest_msrs), right? Looks fine to me. Do you have any numbers or just notice it out of code review? > msr->data = data; > break; > } > -- > Gleb. > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Aug 31, 2009 at 11:04:27AM -0300, Marcelo Tosatti wrote: > On Thu, Aug 27, 2009 at 03:07:30PM +0300, Gleb Natapov wrote: > > No need to call it before each kvm_(set|get)_msr_common() > > > > Signed-off-by: Gleb Natapov <gleb@redhat.com> > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > > index 6b57eed..7494ef1 100644 > > --- a/arch/x86/kvm/vmx.c > > +++ b/arch/x86/kvm/vmx.c > > @@ -1005,9 +1005,9 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata) > > data = vmcs_readl(GUEST_SYSENTER_ESP); > > break; > > default: > > - vmx_load_host_state(to_vmx(vcpu)); > > msr = find_msr_entry(to_vmx(vcpu), msr_index); > > if (msr) { > > + vmx_load_host_state(to_vmx(vcpu)); > > data = msr->data; > > break; > > } > > @@ -1064,9 +1064,9 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data) > > } > > /* Otherwise falls through to kvm_set_msr_common */ > > default: > > - vmx_load_host_state(vmx); > > msr = find_msr_entry(vmx, msr_index); > > if (msr) { > > + vmx_load_host_state(vmx); > > All is needed here save_msrs(vmx->guest_msrs), right? > Yes. Otherwise we return wrong value for cached MSR. > Looks fine to me. Do you have any numbers or just notice it out of code > review? We saw this while profiling IPI ping-pong with x2apic (which uses MSR). This patch improves numbers by ~5us IIRC. -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 6b57eed..7494ef1 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -1005,9 +1005,9 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata) data = vmcs_readl(GUEST_SYSENTER_ESP); break; default: - vmx_load_host_state(to_vmx(vcpu)); msr = find_msr_entry(to_vmx(vcpu), msr_index); if (msr) { + vmx_load_host_state(to_vmx(vcpu)); data = msr->data; break; } @@ -1064,9 +1064,9 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data) } /* Otherwise falls through to kvm_set_msr_common */ default: - vmx_load_host_state(vmx); msr = find_msr_entry(vmx, msr_index); if (msr) { + vmx_load_host_state(vmx); msr->data = data; break; }
No need to call it before each kvm_(set|get)_msr_common() Signed-off-by: Gleb Natapov <gleb@redhat.com> -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html