Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 8feb4a04 authored by Feng Wu's avatar Feng Wu Committed by Paolo Bonzini
Browse files

KVM: Define a new interface kvm_intr_is_single_vcpu() 



This patch defines a new interface kvm_intr_is_single_vcpu(),
which can returns whether the interrupt is for single-CPU or not.

It is used by VT-d PI, since now we only support single-CPU
interrupts, For lowest-priority interrupts, if user configures
it via /proc/irq or uses irqbalance to make it single-CPU, we
can use PI to deliver the interrupts to it. Full functionality
of lowest-priority support will be added later.

Signed-off-by: default avatarFeng Wu <feng.wu@intel.com>
Reviewed-by: default avatarAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent ebbfc765

arch/x86/include/asm/kvm_host.h

+3 −0
Original line number Diff line number Diff line
@@ -1241,4 +1241,7 @@ int x86_set_memory_region(struct kvm *kvm, 
bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu);

bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu);



bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,

			     struct kvm_vcpu **dest_vcpu);



#endif /* _ASM_X86_KVM_HOST_H */

arch/x86/kvm/irq_comm.c

+27 −0
Original line number Diff line number Diff line
@@ -297,6 +297,33 @@ int kvm_set_routing_entry(struct kvm_kernel_irq_routing_entry *e, 
	return r;

}



bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,

			     struct kvm_vcpu **dest_vcpu)

{

	int i, r = 0;

	struct kvm_vcpu *vcpu;



	if (kvm_intr_is_single_vcpu_fast(kvm, irq, dest_vcpu))

		return true;



	kvm_for_each_vcpu(i, vcpu, kvm) {

		if (!kvm_apic_present(vcpu))

			continue;



		if (!kvm_apic_match_dest(vcpu, NULL, irq->shorthand,

					irq->dest_id, irq->dest_mode))

			continue;



		if (++r == 2)

			return false;



		*dest_vcpu = vcpu;

	}



	return r == 1;

}

EXPORT_SYMBOL_GPL(kvm_intr_is_single_vcpu);



#define IOAPIC_ROUTING_ENTRY(irq) \

	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\

	  .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } }

arch/x86/kvm/lapic.c

+59 −0
Original line number Diff line number Diff line
@@ -755,6 +755,65 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src, 
	return ret;

}



bool kvm_intr_is_single_vcpu_fast(struct kvm *kvm, struct kvm_lapic_irq *irq,

			struct kvm_vcpu **dest_vcpu)

{

	struct kvm_apic_map *map;

	bool ret = false;

	struct kvm_lapic *dst = NULL;



	if (irq->shorthand)

		return false;



	rcu_read_lock();

	map = rcu_dereference(kvm->arch.apic_map);



	if (!map)

		goto out;



	if (irq->dest_mode == APIC_DEST_PHYSICAL) {

		if (irq->dest_id == 0xFF)

			goto out;



		if (irq->dest_id >= ARRAY_SIZE(map->phys_map))

			goto out;



		dst = map->phys_map[irq->dest_id];

		if (dst && kvm_apic_present(dst->vcpu))

			*dest_vcpu = dst->vcpu;

		else

			goto out;

	} else {

		u16 cid;

		unsigned long bitmap = 1;

		int i, r = 0;



		if (!kvm_apic_logical_map_valid(map))

			goto out;



		apic_logical_id(map, irq->dest_id, &cid, (u16 *)&bitmap);



		if (cid >= ARRAY_SIZE(map->logical_map))

			goto out;



		for_each_set_bit(i, &bitmap, 16) {

			dst = map->logical_map[cid][i];

			if (++r == 2)

				goto out;

		}



		if (dst && kvm_apic_present(dst->vcpu))

			*dest_vcpu = dst->vcpu;

		else

			goto out;

	}



	ret = true;

out:

	rcu_read_unlock();

	return ret;

}



/*

 * Add a pending IRQ into lapic.

 * Return 1 if successfully added and 0 if discarded.

arch/x86/kvm/lapic.h

+2 −0
Original line number Diff line number Diff line
@@ -168,4 +168,6 @@ bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector); 


void wait_lapic_expire(struct kvm_vcpu *vcpu);



bool kvm_intr_is_single_vcpu_fast(struct kvm *kvm, struct kvm_lapic_irq *irq,

			struct kvm_vcpu **dest_vcpu);

#endif