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 <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Gleb Natapov 2009-08-24 11:54:20 +03:00 committed by Avi Kivity
parent 1a6e4a8c27
commit 46e624b95c
3 changed files with 71 additions and 39 deletions

View file

@ -128,7 +128,17 @@ struct kvm_kernel_irq_routing_entry {
} irqchip;
struct msi_msg msi;
};
struct list_head link;
struct hlist_node link;
};
struct kvm_irq_routing_table {
struct kvm_kernel_irq_routing_entry *rt_entries;
u32 nr_rt_entries;
/*
* Array indexed by gsi. Each entry contains list of irq chips
* the gsi is connected to.
*/
struct hlist_head map[0];
};
struct kvm {
@ -166,7 +176,7 @@ struct kvm {
struct mutex irq_lock;
#ifdef CONFIG_HAVE_KVM_IRQCHIP
struct list_head irq_routing; /* of kvm_kernel_irq_routing_entry */
struct kvm_irq_routing_table *irq_routing;
struct hlist_head mask_notifier_list;
#endif
@ -390,7 +400,12 @@ void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
struct kvm_irq_mask_notifier *kimn);
void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask);
int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level);
#ifdef __KVM_HAVE_IOAPIC
void kvm_get_intr_delivery_bitmask(struct kvm_ioapic *ioapic,
union kvm_ioapic_redirect_entry *entry,
unsigned long *deliver_bitmask);
#endif
int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level);
void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin);
void kvm_register_irq_ack_notifier(struct kvm *kvm,
struct kvm_irq_ack_notifier *kian);

View file

@ -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;
}

View file

@ -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