KVM: PIC: Only commit irq routing when necessary

The current logic updates KVM's view of our interrupt map every time we
change it. While this is nice and bullet proof, it slows things down
badly for me. QEMU spends about 3 seconds on every start telling KVM what
news it has on its routing maps.

Instead, let's just synchronize the whole irq routing map as a whole when
we're done constructing it. For things that change during runtime, we can
still update the routing table on demand.

Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/hw/i386/kvm/ioapic.c b/hw/i386/kvm/ioapic.c
index a3bd519b4de56b536eef088c0e732ca9e85e2c90..abfac3da7a443c225bd59ceaf539697a90fcaf1f 100644 (file)
--- a/hw/i386/kvm/ioapic.c
+++ b/hw/i386/kvm/ioapic.c
@@ -40,6 +40,7 @@ void kvm_pc_setup_irq_routing(bool pci_enabled)
                 }
             }
         }
+        kvm_irqchip_commit_routes(s);
     }
 }
 

diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index 0a6e62a8340d38e0b0a410c9bb5d6368cd3ccd7d..a14cfe949ef787186c38ed3b1dab017f6f5ed3bd 100644 (file)
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -230,6 +230,7 @@ int kvm_set_irq(KVMState *s, int irq, int level);
 int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg);
 
 void kvm_irqchip_add_irq_route(KVMState *s, int gsi, int irqchip, int pin);
+void kvm_irqchip_commit_routes(KVMState *s);
 
 void kvm_put_apic_state(DeviceState *d, struct kvm_lapic_state *kapic);
 void kvm_get_apic_state(DeviceState *d, struct kvm_lapic_state *kapic);

diff --git a/kvm-all.c b/kvm-all.c
index 76435f5759b8034d8a818057887d6be54ef4f664..c757dd262ed19afe1ca53b178f18a99909f53d48 100644 (file)
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -985,7 +985,7 @@ void kvm_init_irq_routing(KVMState *s)
     kvm_arch_init_irq_routing(s);
 }
 
-static void kvm_irqchip_commit_routes(KVMState *s)
+void kvm_irqchip_commit_routes(KVMState *s)
 {
     int ret;
 
@@ -1019,8 +1019,6 @@ static void kvm_add_routing_entry(KVMState *s,
     new->u = entry->u;
 
     set_gsi(s, entry->gsi);
-
-    kvm_irqchip_commit_routes(s);
 }
 
 static int kvm_update_routing_entry(KVMState *s,
@@ -1171,6 +1169,7 @@ int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg)
         route->kroute.u.msi.data = le32_to_cpu(msg.data);
 
         kvm_add_routing_entry(s, &route->kroute);
+        kvm_irqchip_commit_routes(s);
 
         QTAILQ_INSERT_TAIL(&s->msi_hashtab[kvm_hash_msi(msg.data)], route,
                            entry);
@@ -1203,6 +1202,7 @@ int kvm_irqchip_add_msi_route(KVMState *s, MSIMessage msg)
     kroute.u.msi.data = le32_to_cpu(msg.data);
 
     kvm_add_routing_entry(s, &kroute);
+    kvm_irqchip_commit_routes(s);
 
     return virq;
 }