[PATCH v12 19/21] KVM: ARM64: Add a new feature bit for PMUv3
From: Shannon Zhao <hidden>
Date: 2016-02-22 09:37:55
Also in:
kvm, kvmarm
Subsystem:
arm64 port (aarch64 architecture), documentation, kernel virtual machine (kvm), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Jonathan Corbet, Paolo Bonzini, Marc Zyngier, Oliver Upton, Linus Torvalds
From: Shannon Zhao <redacted> To support guest PMUv3, use one bit of the VCPU INIT feature array. Initialize the PMU when initialzing the vcpu with that bit and PMU overflow interrupt set. Signed-off-by: Shannon Zhao <redacted> Acked-by: Peter Maydell <redacted> Reviewed-by: Andrew Jones <redacted> --- Documentation/virtual/kvm/api.txt | 2 ++ arch/arm64/include/asm/kvm_host.h | 2 +- arch/arm64/include/uapi/asm/kvm.h | 1 + arch/arm64/kvm/reset.c | 3 +++ include/kvm/arm_pmu.h | 2 ++ include/uapi/linux/kvm.h | 1 + virt/kvm/arm/pmu.c | 10 ++++++++++ 7 files changed, 20 insertions(+), 1 deletion(-)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 07e4cdf..9684f8d 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt@@ -2577,6 +2577,8 @@ Possible features: Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only). - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 for the CPU. Depends on KVM_CAP_ARM_PSCI_0_2. + - KVM_ARM_VCPU_PMU_V3: Emulate PMUv3 for the CPU. + Depends on KVM_CAP_ARM_PMU_V3. 4.83 KVM_ARM_PREFERRED_TARGET
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 6bab7fb..cb220b7 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h@@ -40,7 +40,7 @@ #define KVM_MAX_VCPUS VGIC_V3_MAX_CPUS -#define KVM_VCPU_MAX_FEATURES 3 +#define KVM_VCPU_MAX_FEATURES 4 int __attribute_const__ kvm_target_cpu(void); int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index 2d4ca4b..6aedbe3 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h@@ -94,6 +94,7 @@ struct kvm_regs { #define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */ #define KVM_ARM_VCPU_EL1_32BIT 1 /* CPU running a 32bit VM */ #define KVM_ARM_VCPU_PSCI_0_2 2 /* CPU uses PSCI v0.2 */ +#define KVM_ARM_VCPU_PMU_V3 3 /* Support guest PMUv3 */ struct kvm_vcpu_init { __u32 target;
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index dfbce78..cf4f28a 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c@@ -77,6 +77,9 @@ int kvm_arch_dev_ioctl_check_extension(long ext) case KVM_CAP_GUEST_DEBUG_HW_WPS: r = get_num_wrps(); break; + case KVM_CAP_ARM_PMU_V3: + r = kvm_arm_support_pmu_v3(); + break; case KVM_CAP_SET_GUEST_DEBUG: r = 1; break;
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index 9cebf03..c7595d6 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h@@ -51,6 +51,7 @@ 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, u64 select_idx); +bool kvm_arm_support_pmu_v3(void); #else struct kvm_pmu { };
@@ -77,6 +78,7 @@ 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, u64 data, u64 select_idx) {} +static inline bool kvm_arm_support_pmu_v3(void) { return false; } #endif #endif
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 9da9051..dc16d30 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h@@ -850,6 +850,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_IOEVENTFD_ANY_LENGTH 122 #define KVM_CAP_HYPERV_SYNIC 123 #define KVM_CAP_S390_RI 124 +#define KVM_CAP_ARM_PMU_V3 125 #ifdef KVM_CAP_IRQ_ROUTING
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
index 0427af8..d5b6eb4 100644
--- a/virt/kvm/arm/pmu.c
+++ b/virt/kvm/arm/pmu.c@@ -383,3 +383,13 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, pmc->perf_event = event; } + +bool kvm_arm_support_pmu_v3(void) +{ + /* + * Check if HW_PERF_EVENTS are supported by checking the number of + * hardware performance counters. This could ensure the presence of + * a physical PMU and CONFIG_PERF_EVENT is selected. + */ + return (perf_num_counters() > 0); +}
--
2.0.4