On Friday, October 14, 2016 8:59 PM, Paolo Bonzini wrote:
> On 14/10/2016 14:30, Wei Wang wrote:
> > PV interrupts (PVI) enables a guest to send interrupts to another via
> > hypercalls.
> >
> > Signed-off-by: Wei Wang <wei.w.wang@xxxxxxxxx>
> > ---
> > pv_interrupt_controller.c | 27 +++++++++++++++++++++++++++
> > 1 file changed, 27 insertions(+)
> > create mode 100644 pv_interrupt_controller.c
> >
> > diff --git a/pv_interrupt_controller.c b/pv_interrupt_controller.c new
> > file mode 100644 index 0000000..5f2431d
> > --- /dev/null
> > +++ b/pv_interrupt_controller.c
> > @@ -0,0 +1,27 @@
> > +
> > +The pv interrupt (PVI) hypercall is proposed to support one guest
> > +sending interrupts to another guest using hypercalls. The following
> > +pseduocode shows how a PVI is sent from the guest:
> > +
> > +#define KVM_HC_PVI 9
> > +kvm_hypercall2(KVM_HC_PVI, guest_uuid, guest_gsi);
> > +
> > +The new hypercall number, KVM_HC_PVI, is used for the purpose of sending
> PVIs.
> > +guest_uuid is used to identify the guest that the interrupt will be sent to.
> > +guest_gsi identifies the interrupt source of that guest.
> > +
> > +The PVI hypercall handler in KVM iterates the VM list (the vm_list
> > +field in the kvm struct), finds the guest with the passed guest_uuid,
> > +and injects an interrupt to the guest with the guest_gsi number.
> > +
> > +Finally, it's about the permission of sending PVI from one guest to another.
> > +In the PVI setup phase, the PVI receiver should get the sender's UUID
> > +(e.g. via the vhost-user protocol extension implemented between QEMUs),
> and pass it to KVM.
> > +Two new fields will be added to the struct kvm{ }:
> > +
> > ++uuid_t uuid; // the guest uuid
> > ++uuid_t pvi_sender_uuid[MAX_NUM]; // the sender's uuid should be
> > ++registered here
> > +
> > +PVI will not be injected to the receiver guest if the sender's uuid
> > +does not appear in the receiver's pvi_sender_uuid table.
> > +
> >
>
> Why would you do that instead of just using the local APIC?...
>
The interrupt will be delivered to LAPIC - the hypercall hander injects the interrupt via kvm_set_irq(kvm, GSI,..), which finally uses LAPIC, right?
Best,
Wei
��.n��������+%������w��{.n�����o�^n�r������&��z�ޗ�zf���h���~����������_��+v���)ߣ�
