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Commit 3dbbdf78 authored by Christoffer Dall's avatar Christoffer Dall Committed by Christoffer Dall
Browse files

KVM: arm/arm64: Report PMU overflow interrupts to userspace irqchip 



When not using an in-kernel VGIC, but instead emulating an interrupt
controller in userspace, we should report the PMU overflow status to
that userspace interrupt controller using the KVM_CAP_ARM_USER_IRQ
feature.

Reviewed-by: default avatarAlexander Graf <agraf@suse.de>
Reviewed-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: default avatarChristoffer Dall <christoffer.dall@linaro.org>
parent d9e13977

arch/arm/kvm/arm.c

+9 −4
Original line number Diff line number Diff line
@@ -635,11 +635,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) 


		/*

		 * If we have a singal pending, or need to notify a userspace

		 * irqchip about timer level changes, then we exit (and update

		 * the timer level state in kvm_timer_update_run below).

		 * irqchip about timer or PMU level changes, then we exit (and

		 * update the timer level state in kvm_timer_update_run

		 * below).

		 */

		if (signal_pending(current) ||

		    kvm_timer_should_notify_user(vcpu)) {

		    kvm_timer_should_notify_user(vcpu) ||

		    kvm_pmu_should_notify_user(vcpu)) {

			ret = -EINTR;

			run->exit_reason = KVM_EXIT_INTR;

		}
@@ -712,7 +714,10 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) 
	}



	/* Tell userspace about in-kernel device output levels */

	if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {

		kvm_timer_update_run(vcpu);

		kvm_pmu_update_run(vcpu);

	}



	if (vcpu->sigset_active)

		sigprocmask(SIG_SETMASK, &sigsaved, NULL);

include/kvm/arm_pmu.h

+7 −0
Original line number Diff line number Diff line
@@ -50,6 +50,8 @@ 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_sync_hwstate(struct kvm_vcpu *vcpu);

bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu);

void kvm_pmu_update_run(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,
@@ -85,6 +87,11 @@ 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_sync_hwstate(struct kvm_vcpu *vcpu) {}

static inline bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu)

{

	return false;

}

static inline void kvm_pmu_update_run(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,

virt/kvm/arm/arch_timer.c

+0 −3
Original line number Diff line number Diff line
@@ -193,9 +193,6 @@ void kvm_timer_update_run(struct kvm_vcpu *vcpu) 
	struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);

	struct kvm_sync_regs *regs = &vcpu->run->s.regs;



	if (likely(irqchip_in_kernel(vcpu->kvm)))

		return;



	/* Populate the device bitmap with the timer states */

	regs->device_irq_level &= ~(KVM_ARM_DEV_EL1_VTIMER |

				    KVM_ARM_DEV_EL1_PTIMER);

virt/kvm/arm/pmu.c

+35 −4
Original line number Diff line number Diff line
@@ -230,11 +230,42 @@ static void kvm_pmu_update_state(struct kvm_vcpu *vcpu) 
		return;



	overflow = !!kvm_pmu_overflow_status(vcpu);

	if (pmu->irq_level != overflow) {

	if (pmu->irq_level == overflow)

		return;



	pmu->irq_level = overflow;

		kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,



	if (likely(irqchip_in_kernel(vcpu->kvm))) {

		int ret;

		ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,

					  pmu->irq_num, overflow);

		WARN_ON(ret);

	}

}



bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu)

{

	struct kvm_pmu *pmu = &vcpu->arch.pmu;

	struct kvm_sync_regs *sregs = &vcpu->run->s.regs;

	bool run_level = sregs->device_irq_level & KVM_ARM_DEV_PMU;



	if (likely(irqchip_in_kernel(vcpu->kvm)))

		return false;



	return pmu->irq_level != run_level;

}



/*

 * Reflect the PMU overflow interrupt output level into the kvm_run structure

 */

void kvm_pmu_update_run(struct kvm_vcpu *vcpu)

{

	struct kvm_sync_regs *regs = &vcpu->run->s.regs;



	/* Populate the timer bitmap for user space */

	regs->device_irq_level &= ~KVM_ARM_DEV_PMU;

	if (vcpu->arch.pmu.irq_level)

		regs->device_irq_level |= KVM_ARM_DEV_PMU;

}



/**