When performing an MSI injection, let's first check if the translation
is already in the cache. If so, let's inject it quickly without
going through the whole translation process.
Tested-by: Andre Przywara <andre.przywara@xxxxxxx>
Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
virt/kvm/arm/vgic/vgic-its.c | 36 ++++++++++++++++++++++++++++++++++++
virt/kvm/arm/vgic/vgic.h | 1 +
2 files changed, 37 insertions(+)
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index e61d3ea0ab40..2be6b66b3856 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -566,6 +566,20 @@ static struct vgic_irq *__vgic_its_check_cache(struct vgic_dist *dist,
return NULL;
}
+static struct vgic_irq *vgic_its_check_cache(struct kvm *kvm, phys_addr_t db,
+ u32 devid, u32 eventid)
+{
+ struct vgic_dist *dist = &kvm->arch.vgic;
+ struct vgic_irq *irq;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&dist->lpi_list_lock, flags);
+ irq = __vgic_its_check_cache(dist, db, devid, eventid);
+ raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags);
+
+ return irq;
+}
+
static void vgic_its_cache_translation(struct kvm *kvm, struct vgic_its *its,
u32 devid, u32 eventid,
struct vgic_irq *irq)
@@ -725,6 +739,25 @@ static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
return 0;
}
+int vgic_its_inject_cached_translation(struct kvm *kvm, struct kvm_msi *msi)
+{
+ struct vgic_irq *irq;
+ unsigned long flags;
+ phys_addr_t db;
+
+ db = (u64)msi->address_hi << 32 | msi->address_lo;
+ irq = vgic_its_check_cache(kvm, db, msi->devid, msi->data);
+
+ if (!irq)
+ return -1;
+
+ raw_spin_lock_irqsave(&irq->irq_lock, flags);
+ irq->pending_latch = true;
+ vgic_queue_irq_unlock(kvm, irq, flags);
+
+ return 0;
+}
+
/*
* Queries the KVM IO bus framework to get the ITS pointer from the given
* doorbell address.
@@ -736,6 +769,9 @@ int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
struct vgic_its *its;
int ret;
+ if (!vgic_its_inject_cached_translation(kvm, msi))
+ return 1;
+
its = vgic_msi_to_its(kvm, msi);
if (IS_ERR(its))
return PTR_ERR(its);
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index c7fb4da2ab3b..83066a81b16a 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -308,6 +308,7 @@ int vgic_copy_lpi_list(struct kvm *kvm, struct kvm_vcpu *vcpu, u32 **intid_ptr);
int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its,
u32 devid, u32 eventid, struct vgic_irq **irq);
struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi);
+int vgic_its_inject_cached_translation(struct kvm *kvm, struct kvm_msi *msi);
void vgic_lpi_translation_cache_init(struct kvm *kvm);
void vgic_lpi_translation_cache_destroy(struct kvm *kvm);
void vgic_its_invalidate_cache(struct kvm *kvm);
--
2.20.1
