[PATCH v2 06/12] KVM: x86: Move TSC scaling logic out of call-back adjust_tsc_offset()

From: Haozhong Zhang
Date: Tue Oct 20 2015 - 03:41:54 EST


For both VMX and SVM, if the 2nd argument of call-back
adjust_tsc_offset() is the host TSC, then adjust_tsc_offset() will scale
it first. This patch moves this common TSC scaling logic to its caller
adjust_tsc_offset_host() and rename the call-back adjust_tsc_offset() to
adjust_tsc_offset_guest().

Signed-off-by: Haozhong Zhang <haozhong.zhang@xxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 15 +--------------
arch/x86/kvm/svm.c | 10 ++--------
arch/x86/kvm/vmx.c | 4 ++--
include/linux/kvm_host.h | 16 ++++++++++++++++
4 files changed, 21 insertions(+), 24 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index d5e820b..b70cebb 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -845,7 +845,7 @@ struct kvm_x86_ops {
int (*get_lpage_level)(void);
bool (*rdtscp_supported)(void);
bool (*invpcid_supported)(void);
- void (*adjust_tsc_offset)(struct kvm_vcpu *vcpu, s64 adjustment, bool host);
+ void (*adjust_tsc_offset_guest)(struct kvm_vcpu *vcpu, s64 adjustment);

void (*set_tdp_cr3)(struct kvm_vcpu *vcpu, unsigned long cr3);

@@ -920,19 +920,6 @@ struct kvm_arch_async_pf {
bool direct_map;
};

-extern struct kvm_x86_ops *kvm_x86_ops;
-
-static inline void adjust_tsc_offset_guest(struct kvm_vcpu *vcpu,
- s64 adjustment)
-{
- kvm_x86_ops->adjust_tsc_offset(vcpu, adjustment, false);
-}
-
-static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment)
-{
- kvm_x86_ops->adjust_tsc_offset(vcpu, adjustment, true);
-}
-
int kvm_mmu_module_init(void);
void kvm_mmu_module_exit(void);

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 481fdd3..9cfc02a 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -984,16 +984,10 @@ static void svm_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
mark_dirty(svm->vmcb, VMCB_INTERCEPTS);
}

-static void svm_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool host)
+static void svm_adjust_tsc_offset_guest(struct kvm_vcpu *vcpu, s64 adjustment)
{
struct vcpu_svm *svm = to_svm(vcpu);

- if (host) {
- if (vcpu->arch.tsc_scaling_ratio != TSC_RATIO_DEFAULT)
- WARN_ON(adjustment < 0);
- adjustment = kvm_scale_tsc(vcpu, (u64)adjustment);
- }
-
svm->vmcb->control.tsc_offset += adjustment;
if (is_guest_mode(vcpu))
svm->nested.hsave->control.tsc_offset += adjustment;
@@ -4361,7 +4355,7 @@ static struct kvm_x86_ops svm_x86_ops = {

.read_tsc_offset = svm_read_tsc_offset,
.write_tsc_offset = svm_write_tsc_offset,
- .adjust_tsc_offset = svm_adjust_tsc_offset,
+ .adjust_tsc_offset_guest = svm_adjust_tsc_offset_guest,
.read_l1_tsc = svm_read_l1_tsc,

.set_tdp_cr3 = set_tdp_cr3,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 7896395..1f72480 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2413,7 +2413,7 @@ static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
}
}

-static void vmx_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool host)
+static void vmx_adjust_tsc_offset_guest(struct kvm_vcpu *vcpu, s64 adjustment)
{
u64 offset = vmcs_read64(TSC_OFFSET);

@@ -10809,7 +10809,7 @@ static struct kvm_x86_ops vmx_x86_ops = {

.read_tsc_offset = vmx_read_tsc_offset,
.write_tsc_offset = vmx_write_tsc_offset,
- .adjust_tsc_offset = vmx_adjust_tsc_offset,
+ .adjust_tsc_offset_guest = vmx_adjust_tsc_offset_guest,
.read_l1_tsc = vmx_read_l1_tsc,

.set_tdp_cr3 = vmx_set_cr3,
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 3556148..95a6bf2 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1186,4 +1186,20 @@ int kvm_arch_update_irqfd_routing(struct kvm *kvm, unsigned int host_irq,

u64 kvm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc);

+extern struct kvm_x86_ops *kvm_x86_ops;
+
+static inline void adjust_tsc_offset_guest(struct kvm_vcpu *vcpu,
+ s64 adjustment)
+{
+ kvm_x86_ops->adjust_tsc_offset_guest(vcpu, adjustment);
+}
+
+static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment)
+{
+ if (vcpu->arch.tsc_scaling_ratio != kvm_default_tsc_scaling_ratio)
+ WARN_ON(adjustment < 0);
+ adjustment = kvm_scale_tsc(vcpu, (u64) adjustment);
+ kvm_x86_ops->adjust_tsc_offset_guest(vcpu, adjustment);
+}
+
#endif
--
2.4.8

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/