@@ -72,14 +72,66 @@ static QLIST_HEAD(ioapic_eoi_client_list,
ioapic_eoi_client) ioapic_eoi_client_list =
QLIST_HEAD_INITIALIZER(ioapic_eoi_client_list);
+#ifdef KVM_EOI_EVENTFD
+static void ioapic_eoi_callback(void *opaque)
+{
+ ioapic_eoi_client *client = opaque;
+
+ if (!event_notifier_test_and_clear(&client->notifier)) {
+ return;
+ }
+
+ client->eoi(client);
+}
+#endif
+
int ioapic_register_eoi_client(ioapic_eoi_client *client)
{
QLIST_INSERT_HEAD(&ioapic_eoi_client_list, client, list);
+
+#ifdef KVM_EOI_EVENTFD
+ if (kvm_enabled() && kvm_irqchip_in_kernel()) {
+ int ret, fd;
+
+ ret = event_notifier_init(&client->notifier, 0);
+ if (ret) {
+ fprintf(stderr, "%s notifier init failed %d\n", __FUNCTION__, ret);
+ return ret;
+ }
+
+ fd = event_notifier_get_fd(&client->notifier);
+ qemu_set_fd_handler(fd, ioapic_eoi_callback, NULL, client);
+
+ ret = kvm_eoi_eventfd(client->irq, fd, KVM_EOI_EVENTFD_FLAG_DEASSERT);
+ if (ret) {
+ fprintf(stderr, "%s eoi eventfd failed %d\n", __FUNCTION__, ret);
+ return ret;
+ }
+ client->notifier_enabled = true;
+ }
+#endif
return 0;
}
void ioapic_unregister_eoi_client(ioapic_eoi_client *client)
{
+#ifdef KVM_EOI_EVENTFD
+ if (kvm_enabled() && kvm_irqchip_in_kernel()) {
+ int ret, fd;
+
+ fd = event_notifier_get_fd(&client->notifier);
+
+ ret = kvm_eoi_eventfd(client->irq, fd, KVM_EOI_EVENTFD_FLAG_DEASSIGN);
+ if (ret) {
+ fprintf(stderr, "%s eoi eventfd failed %d\n", __FUNCTION__, ret);
+ }
+
+ qemu_set_fd_handler(fd, NULL, NULL, NULL);
+
+ event_notifier_cleanup(&client->notifier);
+ client->notifier_enabled = false;
+ }
+#endif
QLIST_REMOVE(client, list);
}
With the KVM irqchip, we need to get the EOI via an eventfd. This adds support for that, abstracting the details to the caller. The get_fd function allows drivers to make further optimizations in handling the EOI. For instance with VFIO, we can make use of an irqfd-like mechanism to have the VFIO kernel module consume the EOI directly, bypassing qemu userspace. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> --- hw/ioapic.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 52 insertions(+), 0 deletions(-)