From 46e624b95c36d729bdf24010fff11d16f6fe94fa Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Mon, 24 Aug 2009 11:54:20 +0300 Subject: KVM: Change irq routing table to use gsi indexed array Use gsi indexed array instead of scanning all entries on each interrupt injection. Signed-off-by: Gleb Natapov Signed-off-by: Avi Kivity --- virt/kvm/irq_comm.c | 88 ++++++++++++++++++++++++++++++++--------------------- virt/kvm/kvm_main.c | 1 - 2 files changed, 53 insertions(+), 36 deletions(-) (limited to 'virt') diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c index 9783f5c43da..81950f6f6fd 100644 --- a/virt/kvm/irq_comm.c +++ b/virt/kvm/irq_comm.c @@ -144,10 +144,12 @@ static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, * = 0 Interrupt was coalesced (previous irq is still pending) * > 0 Number of CPUs interrupt was delivered to */ -int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level) +int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level) { struct kvm_kernel_irq_routing_entry *e; int ret = -1; + struct kvm_irq_routing_table *irq_rt; + struct hlist_node *n; trace_kvm_set_irq(irq, level, irq_source_id); @@ -157,8 +159,9 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level) * IOAPIC. So set the bit in both. The guest will ignore * writes to the unused one. */ - list_for_each_entry(e, &kvm->irq_routing, link) - if (e->gsi == irq) { + irq_rt = kvm->irq_routing; + if (irq < irq_rt->nr_rt_entries) + hlist_for_each_entry(e, n, &irq_rt->map[irq], link) { int r = e->set(e, kvm, irq_source_id, level); if (r < 0) continue; @@ -170,20 +173,23 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level) void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin) { - struct kvm_kernel_irq_routing_entry *e; struct kvm_irq_ack_notifier *kian; struct hlist_node *n; unsigned gsi = pin; + int i; trace_kvm_ack_irq(irqchip, pin); - list_for_each_entry(e, &kvm->irq_routing, link) + for (i = 0; i < kvm->irq_routing->nr_rt_entries; i++) { + struct kvm_kernel_irq_routing_entry *e; + e = &kvm->irq_routing->rt_entries[i]; if (e->type == KVM_IRQ_ROUTING_IRQCHIP && e->irqchip.irqchip == irqchip && e->irqchip.pin == pin) { gsi = e->gsi; break; } + } hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link) if (kian->gsi == gsi) @@ -280,26 +286,30 @@ void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask) kimn->func(kimn, mask); } -static void __kvm_free_irq_routing(struct list_head *irq_routing) -{ - struct kvm_kernel_irq_routing_entry *e, *n; - - list_for_each_entry_safe(e, n, irq_routing, link) - kfree(e); -} - void kvm_free_irq_routing(struct kvm *kvm) { mutex_lock(&kvm->irq_lock); - __kvm_free_irq_routing(&kvm->irq_routing); + kfree(kvm->irq_routing); mutex_unlock(&kvm->irq_lock); } -static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e, +static int setup_routing_entry(struct kvm_irq_routing_table *rt, + struct kvm_kernel_irq_routing_entry *e, const struct kvm_irq_routing_entry *ue) { int r = -EINVAL; int delta; + struct kvm_kernel_irq_routing_entry *ei; + struct hlist_node *n; + + /* + * Do not allow GSI to be mapped to the same irqchip more than once. + * Allow only one to one mapping between GSI and MSI. + */ + hlist_for_each_entry(ei, n, &rt->map[ue->gsi], link) + if (ei->type == KVM_IRQ_ROUTING_MSI || + ue->u.irqchip.irqchip == ei->irqchip.irqchip) + return r; e->gsi = ue->gsi; e->type = ue->type; @@ -332,6 +342,8 @@ static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e, default: goto out; } + + hlist_add_head(&e->link, &rt->map[e->gsi]); r = 0; out: return r; @@ -343,43 +355,49 @@ int kvm_set_irq_routing(struct kvm *kvm, unsigned nr, unsigned flags) { - struct list_head irq_list = LIST_HEAD_INIT(irq_list); - struct list_head tmp = LIST_HEAD_INIT(tmp); - struct kvm_kernel_irq_routing_entry *e = NULL; - unsigned i; + struct kvm_irq_routing_table *new, *old; + u32 i, nr_rt_entries = 0; int r; + for (i = 0; i < nr; ++i) { + if (ue[i].gsi >= KVM_MAX_IRQ_ROUTES) + return -EINVAL; + nr_rt_entries = max(nr_rt_entries, ue[i].gsi); + } + + nr_rt_entries += 1; + + new = kzalloc(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head)) + + (nr * sizeof(struct kvm_kernel_irq_routing_entry)), + GFP_KERNEL); + + if (!new) + return -ENOMEM; + + new->rt_entries = (void *)&new->map[nr_rt_entries]; + + new->nr_rt_entries = nr_rt_entries; + for (i = 0; i < nr; ++i) { r = -EINVAL; - if (ue->gsi >= KVM_MAX_IRQ_ROUTES) - goto out; if (ue->flags) goto out; - r = -ENOMEM; - e = kzalloc(sizeof(*e), GFP_KERNEL); - if (!e) - goto out; - r = setup_routing_entry(e, ue); + r = setup_routing_entry(new, &new->rt_entries[i], ue); if (r) goto out; ++ue; - list_add(&e->link, &irq_list); - e = NULL; } mutex_lock(&kvm->irq_lock); - list_splice(&kvm->irq_routing, &tmp); - INIT_LIST_HEAD(&kvm->irq_routing); - list_splice(&irq_list, &kvm->irq_routing); - INIT_LIST_HEAD(&irq_list); - list_splice(&tmp, &irq_list); + old = kvm->irq_routing; + kvm->irq_routing = new; mutex_unlock(&kvm->irq_lock); + new = old; r = 0; out: - kfree(e); - __kvm_free_irq_routing(&irq_list); + kfree(new); return r; } diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 22b520b5441..3bee9489277 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -957,7 +957,6 @@ static struct kvm *kvm_create_vm(void) if (IS_ERR(kvm)) goto out; #ifdef CONFIG_HAVE_KVM_IRQCHIP - INIT_LIST_HEAD(&kvm->irq_routing); INIT_HLIST_HEAD(&kvm->mask_notifier_list); #endif -- cgit v1.2.3