kvm/irqchip: Speed up KVM_SET_GSI_ROUTING

[firefly-linux-kernel-4.4.55.git] / virt / kvm / irq_comm.c

diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index e2e6b4473a96fafc98dc85aa6c2e8fa49fcd1c09..ced4a542a031313cefd0915bbfa3943d3433c240 100644 (file)
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -163,6 +163,7 @@ int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq, int level)
        struct kvm_kernel_irq_routing_entry *e;
        int ret = -EINVAL;
        struct kvm_irq_routing_table *irq_rt;
+       int idx;
 
        trace_kvm_set_irq(irq, level, irq_source_id);
 
@@ -174,8 +175,8 @@ int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq, int level)
         * Since there's no easy way to do this, we only support injecting MSI
         * which is limited to 1:1 GSI mapping.
         */
-       rcu_read_lock();
-       irq_rt = rcu_dereference(kvm->irq_routing);
+       idx = srcu_read_lock(&kvm->irq_srcu);
+       irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
        if (irq < irq_rt->nr_rt_entries)
                hlist_for_each_entry(e, &irq_rt->map[irq], link) {
                        if (likely(e->type == KVM_IRQ_ROUTING_MSI))
@@ -184,7 +185,7 @@ int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq, int level)
                                ret = -EWOULDBLOCK;
                        break;
                }
-       rcu_read_unlock();
+       srcu_read_unlock(&kvm->irq_srcu, idx);
        return ret;
 }
 
@@ -253,22 +254,22 @@ void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
        mutex_lock(&kvm->irq_lock);
        hlist_del_rcu(&kimn->link);
        mutex_unlock(&kvm->irq_lock);
-       synchronize_rcu();
+       synchronize_srcu(&kvm->irq_srcu);
 }
 
 void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
                             bool mask)
 {
        struct kvm_irq_mask_notifier *kimn;
-       int gsi;
+       int idx, gsi;
 
-       rcu_read_lock();
-       gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
+       idx = srcu_read_lock(&kvm->irq_srcu);
+       gsi = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu)->chip[irqchip][pin];
        if (gsi != -1)
                hlist_for_each_entry_rcu(kimn, &kvm->mask_notifier_list, link)
                        if (kimn->irq == gsi)
                                kimn->func(kimn, mask);
-       rcu_read_unlock();
+       srcu_read_unlock(&kvm->irq_srcu, idx);
 }
 
 int kvm_set_routing_entry(struct kvm_irq_routing_table *rt,