>From: Shannon Zhao<shannon.zhao@xxxxxxxxxx>
>
>When calling perf_event_create_kernel_counter to create perf_event,
>assign a overflow handler. Then when the perf event overflows, set the
>corresponding bit of guest PMOVSSET register. If this counter is enabled
>and its interrupt is enabled as well, kick the vcpu to sync the
>interrupt.
>
>On VM entry, if there is counter overflowed, inject the interrupt with
>the level set to 1. Otherwise, inject the interrupt with the level set
>to 0.
>
>Signed-off-by: Shannon Zhao<shannon.zhao@xxxxxxxxxx>
>Reviewed-by: Marc Zyngier<marc.zyngier@xxxxxxx>
>Reviewed-by: Andrew Jones<drjones@xxxxxxxxxx>
>---
> arch/arm/kvm/arm.c | 2 ++
> include/kvm/arm_pmu.h | 2 ++
> virt/kvm/arm/pmu.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++++-
> 3 files changed, 53 insertions(+), 1 deletion(-)
>
>diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
>index dda1959..f54264c 100644
>--- a/arch/arm/kvm/arm.c
>+++ b/arch/arm/kvm/arm.c
>@@ -28,6 +28,7 @@
> #include <linux/sched.h>
> #include <linux/kvm.h>
> #include <trace/events/kvm.h>
>+#include <kvm/arm_pmu.h>
>
> #define CREATE_TRACE_POINTS
> #include "trace.h"
>@@ -577,6 +578,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
> * non-preemptible context.
> */
> preempt_disable();
>+ kvm_pmu_flush_hwstate(vcpu);
> kvm_timer_flush_hwstate(vcpu);
> kvm_vgic_flush_hwstate(vcpu);
>
>diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
>index 1f4bfa2..44a3c75 100644
>--- a/include/kvm/arm_pmu.h
>+++ b/include/kvm/arm_pmu.h
>@@ -44,6 +44,7 @@ u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu);
> void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val);
> void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val);
> void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u64 val);
>+void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu);
> void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val);
> void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val);
> void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
>@@ -67,6 +68,7 @@ static inline u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu)
> static inline void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val) {}
> static inline void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val) {}
> static inline void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u64 val) {}
>+static inline void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) {}
> static inline void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val) {}
> static inline void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val) {}
> static inline void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu,
>diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
>index c8ea825..5f983cb 100644
>--- a/virt/kvm/arm/pmu.c
>+++ b/virt/kvm/arm/pmu.c
>@@ -21,6 +21,7 @@
> #include <linux/perf_event.h>
> #include <asm/kvm_emulate.h>
> #include <kvm/arm_pmu.h>
>+#include <kvm/arm_vgic.h>
>
> /**
> * kvm_pmu_get_counter_value - get PMU counter value
>@@ -180,6 +181,52 @@ void kvm_pmu_overflow_set(struct kvm_vcpu *vcpu, u64 val)
> }
>
> /**
>+ * kvm_pmu_flush_hwstate - flush pmu state to cpu
>+ * @vcpu: The vcpu pointer
>+ *
>+ * Inject virtual PMU IRQ if IRQ is pending for this cpu.
>+ */
>+void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu)
>+{
>+ struct kvm_pmu *pmu = &vcpu->arch.pmu;
>+ u64 overflow;
>+
>+ if (!kvm_arm_pmu_v3_ready(vcpu))
>+ return;
>+
>+ if (!(vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMCR_E))
>+ return;
