[PATCH v3 3/5] KVM: LAPIC: Expose per-vCPU timer_advance_ns to userspace
From: Wanpeng Li
Expose per-vCPU timer_advance_ns to userspace, so it is able to
query the auto-adjusted value.
Cc: Paolo Bonzini
Cc: Radim Krčmář
Cc: Sean Christopherson
Cc: Liran Alon
Signed-off-by: Wanpeng Li
---
arch/x86/kvm/debugfs.c | 16
1 file changed, 16 insertions(+)
diff --git a/arch/x86/kvm/debugfs.c b/arch/x86/kvm/debugfs.c
index c19c7ed..a6f1f93 100644
--- a/arch/x86/kvm/debugfs.c
+++ b/arch/x86/kvm/debugfs.c
@@ -9,12 +9,22 @@
*/
#include
#include
+#include "lapic.h"
bool kvm_arch_has_vcpu_debugfs(void)
{
return true;
}
+static int vcpu_get_timer_advance_ns(void *data, u64 *val)
+{
+ struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
+ *val = vcpu->arch.apic->lapic_timer.timer_advance_ns;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(vcpu_timer_advance_ns_fops, vcpu_get_timer_advance_ns,
NULL, "%llu\n");
+
static int vcpu_get_tsc_offset(void *data, u64 *val)
{
struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
@@ -51,6 +61,12 @@ int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
if (!ret)
return -ENOMEM;
+ ret = debugfs_create_file("lapic_timer_advance_ns", 0444,
+ vcpu->debugfs_dentry,
+ vcpu,
_timer_advance_ns_fops);
+ if (!ret)
+ return -ENOMEM;
+
if (kvm_has_tsc_control) {
ret = debugfs_create_file("tsc-scaling-ratio", 0444,
vcpu->debugfs_dentry,
--
2.7.4
Re: [PATCH v3 3/5] KVM: LAPIC: Expose per-vCPU timer_advance_ns to userspace
On Sat, 18 May 2019 at 04:05, Sean Christopherson
wrote:
>
> On Thu, May 16, 2019 at 11:06:18AM +0800, Wanpeng Li wrote:
> > From: Wanpeng Li
> >
> > Expose per-vCPU timer_advance_ns to userspace, so it is able to
> > query the auto-adjusted value.
> >
> > Cc: Paolo Bonzini
> > Cc: Radim Krčmář
> > Cc: Sean Christopherson
> > Cc: Liran Alon
> > Signed-off-by: Wanpeng Li
> > ---
> > arch/x86/kvm/debugfs.c | 16
> > 1 file changed, 16 insertions(+)
> >
> > diff --git a/arch/x86/kvm/debugfs.c b/arch/x86/kvm/debugfs.c
> > index c19c7ed..a6f1f93 100644
> > --- a/arch/x86/kvm/debugfs.c
> > +++ b/arch/x86/kvm/debugfs.c
> > @@ -9,12 +9,22 @@
> > */
> > #include
> > #include
> > +#include "lapic.h"
> >
> > bool kvm_arch_has_vcpu_debugfs(void)
> > {
> > return true;
> > }
> >
> > +static int vcpu_get_timer_advance_ns(void *data, u64 *val)
> > +{
> > + struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
> > + *val = vcpu->arch.apic->lapic_timer.timer_advance_ns;
>
> This needs to ensure to check lapic_in_kernel() to ensure apic isn't NULL.
> Actually, I think we can skip creation of the parameter entirely if
> lapic_in_kernel() is false. VMX and SVM both instantiate the lapic
> during kvm_arch_vcpu_create(), which is (obviously) called before
> kvm_arch_create_vcpu_debugfs().
Handle this in v4.
>
> > + return 0;
> > +}
> > +
> > +DEFINE_SIMPLE_ATTRIBUTE(vcpu_timer_advance_ns_fops,
> > vcpu_get_timer_advance_ns, NULL, "%llu\n");
> > +
> > static int vcpu_get_tsc_offset(void *data, u64 *val)
> > {
> > struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
> > @@ -51,6 +61,12 @@ int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
> > if (!ret)
> > return -ENOMEM;
> >
> > + ret = debugfs_create_file("lapic_timer_advance_ns", 0444,
> > + vcpu->debugfs_dentry,
> > + vcpu,
> > _timer_advance_ns_fops);
> > + if (!ret)
> > + return -ENOMEM;
> > +
> > if (kvm_has_tsc_control) {
> > ret = debugfs_create_file("tsc-scaling-ratio", 0444,
> > vcpu->debugfs_dentry,
> > --
> > 2.7.4
> >
Re: [PATCH v3 3/5] KVM: LAPIC: Expose per-vCPU timer_advance_ns to userspace
On Thu, May 16, 2019 at 11:06:18AM +0800, Wanpeng Li wrote:
> From: Wanpeng Li
>
> Expose per-vCPU timer_advance_ns to userspace, so it is able to
> query the auto-adjusted value.
>
> Cc: Paolo Bonzini
> Cc: Radim Krčmář
> Cc: Sean Christopherson
> Cc: Liran Alon
> Signed-off-by: Wanpeng Li
> ---
> arch/x86/kvm/debugfs.c | 16
> 1 file changed, 16 insertions(+)
>
> diff --git a/arch/x86/kvm/debugfs.c b/arch/x86/kvm/debugfs.c
> index c19c7ed..a6f1f93 100644
> --- a/arch/x86/kvm/debugfs.c
> +++ b/arch/x86/kvm/debugfs.c
> @@ -9,12 +9,22 @@
> */
> #include
> #include
> +#include "lapic.h"
>
> bool kvm_arch_has_vcpu_debugfs(void)
> {
> return true;
> }
>
> +static int vcpu_get_timer_advance_ns(void *data, u64 *val)
> +{
> + struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
> + *val = vcpu->arch.apic->lapic_timer.timer_advance_ns;
This needs to ensure to check lapic_in_kernel() to ensure apic isn't NULL.
Actually, I think we can skip creation of the parameter entirely if
lapic_in_kernel() is false. VMX and SVM both instantiate the lapic
during kvm_arch_vcpu_create(), which is (obviously) called before
kvm_arch_create_vcpu_debugfs().
> + return 0;
> +}
> +
> +DEFINE_SIMPLE_ATTRIBUTE(vcpu_timer_advance_ns_fops,
> vcpu_get_timer_advance_ns, NULL, "%llu\n");
> +
> static int vcpu_get_tsc_offset(void *data, u64 *val)
> {
> struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
> @@ -51,6 +61,12 @@ int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
> if (!ret)
> return -ENOMEM;
>
> + ret = debugfs_create_file("lapic_timer_advance_ns", 0444,
> + vcpu->debugfs_dentry,
> + vcpu,
> _timer_advance_ns_fops);
> + if (!ret)
> + return -ENOMEM;
> +
> if (kvm_has_tsc_control) {
> ret = debugfs_create_file("tsc-scaling-ratio", 0444,
> vcpu->debugfs_dentry,
> --
> 2.7.4
>
[PATCH v3 3/5] KVM: LAPIC: Expose per-vCPU timer_advance_ns to userspace
From: Wanpeng Li
Expose per-vCPU timer_advance_ns to userspace, so it is able to
query the auto-adjusted value.
Cc: Paolo Bonzini
Cc: Radim Krčmář
Cc: Sean Christopherson
Cc: Liran Alon
Signed-off-by: Wanpeng Li
---
arch/x86/kvm/debugfs.c | 16
1 file changed, 16 insertions(+)
diff --git a/arch/x86/kvm/debugfs.c b/arch/x86/kvm/debugfs.c
index c19c7ed..a6f1f93 100644
--- a/arch/x86/kvm/debugfs.c
+++ b/arch/x86/kvm/debugfs.c
@@ -9,12 +9,22 @@
*/
#include
#include
+#include "lapic.h"
bool kvm_arch_has_vcpu_debugfs(void)
{
return true;
}
+static int vcpu_get_timer_advance_ns(void *data, u64 *val)
+{
+ struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
+ *val = vcpu->arch.apic->lapic_timer.timer_advance_ns;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(vcpu_timer_advance_ns_fops, vcpu_get_timer_advance_ns,
NULL, "%llu\n");
+
static int vcpu_get_tsc_offset(void *data, u64 *val)
{
struct kvm_vcpu *vcpu = (struct kvm_vcpu *) data;
@@ -51,6 +61,12 @@ int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
if (!ret)
return -ENOMEM;
+ ret = debugfs_create_file("lapic_timer_advance_ns", 0444,
+ vcpu->debugfs_dentry,
+ vcpu,
_timer_advance_ns_fops);
+ if (!ret)
+ return -ENOMEM;
+
if (kvm_has_tsc_control) {
ret = debugfs_create_file("tsc-scaling-ratio", 0444,
vcpu->debugfs_dentry,
--
2.7.4
