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 <lkp@intel.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/202205161814.KQHpOzsJ-lkp@intel.com
This commit is contained in:
Marc Zyngier 2022-05-16 13:02:24 +01:00
parent 722625c6f4
commit 20492a62b9
5 changed files with 31 additions and 21 deletions

View file

@ -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

View file

@ -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

View file

@ -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

View file

@ -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.

View file

@ -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