One more IEC notifier is added to let msi routes know about the IEC
changes. When interrupt invalidation happens, all registered msi routes
will be updated for all PCI devices.
Since both vfio and vhost are possible gsi route consumers, this patch
will go one step further to keep them safe in split irqchip mode and
when irqfd is enabled.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
[move trace-events lines into target-i386/trace-events]
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Adding two hooks to be notified when adding/removing msi routes. There
are two kinds of MSI routes:
- in kvm_irqchip_add_irq_route(): before assigning IRQFD. Used by
vhost, vfio, etc.
- in kvm_irqchip_send_msi(): when sending direct MSI message, if
direct MSI not allowed, we will first create one MSI route entry
in the kernel, then trigger it.
This patch only hooks the first one (irqfd case). We do not need to
take care for the 2nd one, since it's only used by QEMU userspace
(kvm-apic) and the messages will always do in-time translation when
triggered. While we need to note them down for the 1st one, so that we
can notify the kernel when cache invalidation happens.
Also, we do not hook IOAPIC msi routes (we have explicit notifier for
IOAPIC to keep its cache updated). We only need to care about irqfd
users.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In split irqchip mode, IOAPIC is working in user space, only update
kernel irq routes when entry changed. When IR is enabled, we directly
update the kernel with translated messages. It works just like a kernel
cache for the remapping entries.
Since KVM irqfd is using kernel gsi routes to deliver interrupts, as
long as we can support split irqchip, we will support irqfd as
well. Also, since kernel gsi routes will cache translated interrupts,
irqfd delivery will not suffer from any performance impact due to IR.
And, since we supported irqfd, vhost devices will be able to work
seamlessly with IR now. Logically this should contain both vhost-net and
vhost-user case.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[move trace-events lines into target-i386/trace-events]
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
