From: Marc Zyngier maz@kernel.org
mainline inclusion from mainline-v5.4-rc1 commit 86a7dae884f38e11f3af8137ddf1fb969cd2699c category: feature feature: ITS translation cache
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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@arm.com Reviewed-by: Eric Auger eric.auger@redhat.com Signed-off-by: Marc Zyngier maz@kernel.org Signed-off-by: Zenghui Yu yuzenghui@huawei.com Reviewed-by: Hailiang Zhang zhang.zhanghailiang@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- 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 a7c7270..b9ee395 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -588,6 +588,20 @@ 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) @@ -747,6 +761,25 @@ 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. @@ -758,6 +791,9 @@ 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 f5ae753..04e2f23 100644 --- a/virt/kvm/arm/vgic/vgic.h +++ b/virt/kvm/arm/vgic/vgic.h @@ -319,6 +319,7 @@ static inline bool vgic_dist_overlap(struct kvm *kvm, gpa_t base, size_t size) 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);