2024-01-26 11:24:40

by Zhang, Xiong Y

[permalink] [raw]
Subject: [RFC PATCH 20/41] KVM: x86/pmu: Introduce PMU operation prototypes for save/restore PMU context

From: Mingwei Zhang <[email protected]>

Plumb through kvm_pmu_ops with these two extra functions to allow pmu
context switch.

Signed-off-by: Mingwei Zhang <[email protected]>
---
arch/x86/include/asm/kvm-x86-pmu-ops.h | 2 ++
arch/x86/kvm/pmu.c | 14 ++++++++++++++
arch/x86/kvm/pmu.h | 4 ++++
3 files changed, 20 insertions(+)

diff --git a/arch/x86/include/asm/kvm-x86-pmu-ops.h b/arch/x86/include/asm/kvm-x86-pmu-ops.h
index a2acf0afee5d..ee201ac95f57 100644
--- a/arch/x86/include/asm/kvm-x86-pmu-ops.h
+++ b/arch/x86/include/asm/kvm-x86-pmu-ops.h
@@ -26,6 +26,8 @@ KVM_X86_PMU_OP(reset)
KVM_X86_PMU_OP_OPTIONAL(deliver_pmi)
KVM_X86_PMU_OP_OPTIONAL(cleanup)
KVM_X86_PMU_OP_OPTIONAL(passthrough_pmu_msrs)
+KVM_X86_PMU_OP_OPTIONAL(save_pmu_context)
+KVM_X86_PMU_OP_OPTIONAL(restore_pmu_context)

#undef KVM_X86_PMU_OP
#undef KVM_X86_PMU_OP_OPTIONAL
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index d83746f93392..9d737f5b96bf 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -898,3 +898,17 @@ void kvm_pmu_passthrough_pmu_msrs(struct kvm_vcpu *vcpu)
{
static_call_cond(kvm_x86_pmu_passthrough_pmu_msrs)(vcpu);
}
+
+void kvm_pmu_save_pmu_context(struct kvm_vcpu *vcpu)
+{
+ lockdep_assert_irqs_disabled();
+
+ static_call_cond(kvm_x86_pmu_save_pmu_context)(vcpu);
+}
+
+void kvm_pmu_restore_pmu_context(struct kvm_vcpu *vcpu)
+{
+ lockdep_assert_irqs_disabled();
+
+ static_call_cond(kvm_x86_pmu_restore_pmu_context)(vcpu);
+}
diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h
index d575808c7258..a4c0b2e2c24b 100644
--- a/arch/x86/kvm/pmu.h
+++ b/arch/x86/kvm/pmu.h
@@ -34,6 +34,8 @@ struct kvm_pmu_ops {
void (*deliver_pmi)(struct kvm_vcpu *vcpu);
void (*cleanup)(struct kvm_vcpu *vcpu);
void (*passthrough_pmu_msrs)(struct kvm_vcpu *vcpu);
+ void (*save_pmu_context)(struct kvm_vcpu *vcpu);
+ void (*restore_pmu_context)(struct kvm_vcpu *vcpu);

const u64 EVENTSEL_EVENT;
const int MAX_NR_GP_COUNTERS;
@@ -288,6 +290,8 @@ void kvm_pmu_destroy(struct kvm_vcpu *vcpu);
int kvm_vm_ioctl_set_pmu_event_filter(struct kvm *kvm, void __user *argp);
void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 perf_hw_id);
void kvm_pmu_passthrough_pmu_msrs(struct kvm_vcpu *vcpu);
+void kvm_pmu_save_pmu_context(struct kvm_vcpu *vcpu);
+void kvm_pmu_restore_pmu_context(struct kvm_vcpu *vcpu);

bool is_vmware_backdoor_pmc(u32 pmc_idx);

--
2.34.1