From 20492a62b99bd4367b79a76ca288d018f11980db Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 16 May 2022 13:02:24 +0100 Subject: [PATCH] KVM: arm64: pmu: Restore compilation when HW_PERF_EVENTS isn't selected Moving kvm_pmu_events into the vcpu (and refering to it) broke the somewhat unusual case where the kernel has no support for a PMU at all. In order to solve this, move things around a bit so that we can easily avoid refering to the pmu structure outside of PMU-aware code. As a bonus, pmu.c isn't compiled in when HW_PERF_EVENTS isn't selected. Reported-by: kernel test robot Reviewed-by: Fuad Tabba Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/202205161814.KQHpOzsJ-lkp@intel.com --- arch/arm64/include/asm/kvm_host.h | 6 ------ arch/arm64/kvm/Makefile | 4 ++-- arch/arm64/kvm/arm.c | 13 ------------- arch/arm64/kvm/hyp/nvhe/switch.c | 5 +++++ include/kvm/arm_pmu.h | 24 ++++++++++++++++++++++++ 5 files changed, 31 insertions(+), 21 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index efca5a6..ef774b8 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -789,10 +789,6 @@ void kvm_arch_vcpu_put_debug_state_flags(struct kvm_vcpu *vcpu); #ifdef CONFIG_KVM void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr); void kvm_clr_pmu_events(u32 clr); - -struct kvm_pmu_events *kvm_get_pmu_events(void); -void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu); -void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu); #else static inline void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) {} static inline void kvm_clr_pmu_events(u32 clr) {} @@ -824,8 +820,6 @@ bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu); #define kvm_has_mte(kvm) \ (system_supports_mte() && \ test_bit(KVM_ARCH_FLAG_MTE_ENABLED, &(kvm)->arch.flags)) -#define kvm_vcpu_has_pmu(vcpu) \ - (test_bit(KVM_ARM_VCPU_PMU_V3, (vcpu)->arch.features)) int kvm_trng_call(struct kvm_vcpu *vcpu); #ifdef CONFIG_KVM diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 261644b..aa127ae 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -13,7 +13,7 @@ obj-$(CONFIG_KVM) += hyp/ kvm-y += arm.o mmu.o mmio.o psci.o hypercalls.o pvtime.o \ inject_fault.o va_layout.o handle_exit.o \ guest.o debug.o reset.o sys_regs.o \ - vgic-sys-reg-v3.o fpsimd.o pmu.o pkvm.o \ + vgic-sys-reg-v3.o fpsimd.o pkvm.o \ arch_timer.o trng.o vmid.o \ vgic/vgic.o vgic/vgic-init.o \ vgic/vgic-irqfd.o vgic/vgic-v2.o \ @@ -22,7 +22,7 @@ kvm-y += arm.o mmu.o mmio.o psci.o hypercalls.o pvtime.o \ vgic/vgic-mmio-v3.o vgic/vgic-kvm-device.o \ vgic/vgic-its.o vgic/vgic-debug.o -kvm-$(CONFIG_HW_PERF_EVENTS) += pmu-emul.o +kvm-$(CONFIG_HW_PERF_EVENTS) += pmu-emul.o pmu.o always-y := hyp_constants.h hyp-constants.s diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index aa1b15e..b3821c4 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -751,19 +751,6 @@ static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) return ret; } -/* - * Updates the vcpu's view of the pmu events for this cpu. - * Must be called before every vcpu run after disabling interrupts, to ensure - * that an interrupt cannot fire and update the structure. - */ -static void kvm_pmu_update_vcpu_events(struct kvm_vcpu *vcpu) -{ - if (has_vhe() || !kvm_vcpu_has_pmu(vcpu)) - return; - - vcpu->arch.pmu.events = *kvm_get_pmu_events(); -} - /** * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code * @vcpu: The VCPU pointer diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c index ff7b29f..c7cd203 100644 --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -123,6 +123,7 @@ static void __hyp_vgic_restore_state(struct kvm_vcpu *vcpu) /** * Disable host events, enable guest events */ +#ifdef CONFIG_HW_PERF_EVENTS static bool __pmu_switch_to_guest(struct kvm_vcpu *vcpu) { struct kvm_pmu_events *pmu = &vcpu->arch.pmu.events; @@ -149,6 +150,10 @@ static void __pmu_switch_to_host(struct kvm_vcpu *vcpu) if (pmu->events_host) write_sysreg(pmu->events_host, pmcntenset_el0); } +#else +#define __pmu_switch_to_guest(v) ({ false; }) +#define __pmu_switch_to_host(v) do {} while (0) +#endif /** * Handler for protected VM MSR, MRS or System instruction execution in AArch64. diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h index 35a0903..c0b868c 100644 --- a/include/kvm/arm_pmu.h +++ b/include/kvm/arm_pmu.h @@ -72,6 +72,25 @@ int kvm_arm_pmu_v3_get_attr(struct kvm_vcpu *vcpu, int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr); int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu); + +struct kvm_pmu_events *kvm_get_pmu_events(void); +void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu); +void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu); + +#define kvm_vcpu_has_pmu(vcpu) \ + (test_bit(KVM_ARM_VCPU_PMU_V3, (vcpu)->arch.features)) + +/* + * Updates the vcpu's view of the pmu events for this cpu. + * Must be called before every vcpu run after disabling interrupts, to ensure + * that an interrupt cannot fire and update the structure. + */ +#define kvm_pmu_update_vcpu_events(vcpu) \ + do { \ + if (!has_vhe() && kvm_vcpu_has_pmu(vcpu)) \ + vcpu->arch.pmu.events = *kvm_get_pmu_events(); \ + } while (0) + #else struct kvm_pmu { }; @@ -133,6 +152,11 @@ static inline u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) return 0; } +#define kvm_vcpu_has_pmu(vcpu) ({ false; }) +static inline void kvm_pmu_update_vcpu_events(struct kvm_vcpu *vcpu) {} +static inline void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu) {} +static inline void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu) {} + #endif #endif -- 2.7.4