We can deliver certain interrupts, notably MSI,
from atomic context. Use kvm_set_irq_inatomic,
to implement an irq handler for msi.
This reduces the pressure on scheduler in case
where host and guest irq share a host cpu.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
+static irqreturn_t kvm_assigned_dev_msi(int irq, void *dev_id)
+{
+ struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+ int ret = kvm_set_irq_inatomic(assigned_dev->kvm,
+ assigned_dev->irq_source_id,
+ assigned_dev->guest_irq, 1);
+ return unlikely(ret == -EWOULDBLOCK) ? IRQ_WAKE_THREAD : IRQ_HANDLED;
+}
+
static irqreturn_t kvm_assigned_dev_thread_msi(int irq, void *dev_id)
{
struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
static irqreturn_t kvm_assigned_dev_thread_msi(int irq, void *dev_id)
{
struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
#endif
#ifdef __KVM_HAVE_MSIX
#endif
#ifdef __KVM_HAVE_MSIX
+static irqreturn_t kvm_assigned_dev_msix(int irq, void *dev_id)
+{
+ struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+ int index = find_index_from_host_irq(assigned_dev, irq);
+ u32 vector;
+ int ret = 0;
+
+ if (index >= 0) {
+ vector = assigned_dev->guest_msix_entries[index].vector;
+ ret = kvm_set_irq_inatomic(assigned_dev->kvm,
+ assigned_dev->irq_source_id,
+ vector, 1);
+ }
+
+ return unlikely(ret == -EWOULDBLOCK) ? IRQ_WAKE_THREAD : IRQ_HANDLED;
+}
+
static irqreturn_t kvm_assigned_dev_thread_msix(int irq, void *dev_id)
{
struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
static irqreturn_t kvm_assigned_dev_thread_msix(int irq, void *dev_id)
{
struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
-static irqreturn_t kvm_assigned_dev_msi(int irq, void *dev_id)
-{
- return IRQ_WAKE_THREAD;
-}
-
static int assigned_device_enable_host_msi(struct kvm *kvm,
struct kvm_assigned_dev_kernel *dev)
{
static int assigned_device_enable_host_msi(struct kvm *kvm,
struct kvm_assigned_dev_kernel *dev)
{
#endif
#ifdef __KVM_HAVE_MSIX
#endif
#ifdef __KVM_HAVE_MSIX
-static irqreturn_t kvm_assigned_dev_msix(int irq, void *dev_id)
-{
- return IRQ_WAKE_THREAD;
-}
-
static int assigned_device_enable_host_msix(struct kvm *kvm,
struct kvm_assigned_dev_kernel *dev)
{
static int assigned_device_enable_host_msix(struct kvm *kvm,
struct kvm_assigned_dev_kernel *dev)
{