Il 22/07/2013 16:18, Vincenzo Maffione ha scritto:
> Actually our research group (at University of Pisa) is working on some
> paravirtualization extensions of the e1000 NIC emulation that needs
> KVM_IRQFD_FLAG_RESAMPLE support. This is one of the reasons why I'm
> proposing this patch.
>
> Do you suggest modifying vfio_enable_intx_kvm() to take advantage of
> the patch? I haven't addressed vfio only because I wasn't sure I am
> "permitted" to do that.
If you have a patch to do that, I guess it's welcome. :)
Otherwise, this patch makes sense from the point of view of supporting
the KVM API in a more complete manner.
Paolo
>
>
> Thanks,
> Vincenzo
>
> 2013/7/22 Alex Williamson <alex.william...@redhat.com>:
>>
>> On Mon, 2013-07-22 at 12:43 +0200, Vincenzo Maffione wrote:
>>> From e59e35380380c2986cd0164f11dcd8a07a8e4e59 Mon Sep 17 00:00:00 2001
>>> From: Vincenzo Maffione <v.maffi...@gmail.com>
>>> Date: Mon, 22 Jul 2013 11:51:33 +0200
>>> Subject: [PATCH] kvm: add KVM_IRQFD_FLAG_RESAMPLE support
>>>
>>> Added an EventNotifier* parameter to
>>> kvm-all.c:kvm_irqchip_add_irqfd_notifier(), in order to give KVM
>>> another eventfd to be used as "resamplefd". See the documentation
>>> in the linux kernel sources in Documentation/virtual/kvm/api.txt
>>> (section 4.75) for more details.
>>> When the added parameter is passed NULL, the behaviour of the
>>> function is unchanged with respect to the previous versions.
>>>
>>> Signed-off-by: Vincenzo Maffione <v.maffi...@gmail.com>
>>> ---
>>> hw/misc/vfio.c | 4 ++--
>>> hw/virtio/virtio-pci.c | 2 +-
>>> include/sysemu/kvm.h | 3 ++-
>>> kvm-all.c | 17 +++++++++++++----
>>> 4 files changed, 18 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
>>> index ad8ce77..54af34a 100644
>>> --- a/hw/misc/vfio.c
>>> +++ b/hw/misc/vfio.c
>>> @@ -646,7 +646,7 @@ static int vfio_msix_vector_do_use(PCIDevice
>>> *pdev, unsigned int nr,
>>> vector->virq = msg ? kvm_irqchip_add_msi_route(kvm_state, *msg) : -1;
>>> if (vector->virq < 0 ||
>>> kvm_irqchip_add_irqfd_notifier(kvm_state, &vector->interrupt,
>>> - vector->virq) < 0) {
>>> + NULL, vector->virq) < 0) {
>>> if (vector->virq >= 0) {
>>> kvm_irqchip_release_virq(kvm_state, vector->virq);
>>> vector->virq = -1;
>>> @@ -814,7 +814,7 @@ retry:
>>> vector->virq = kvm_irqchip_add_msi_route(kvm_state, msg);
>>> if (vector->virq < 0 ||
>>> kvm_irqchip_add_irqfd_notifier(kvm_state, &vector->interrupt,
>>> - vector->virq) < 0) {
>>> + NULL, vector->virq) < 0) {
>>> qemu_set_fd_handler(event_notifier_get_fd(&vector->interrupt),
>>> vfio_msi_interrupt, NULL, vector);
>>> }
>>
>>
>> Why doesn't this address the only current user of
>> KVM_IRQFD_FLAG_RESAMPLE, vfio_enable_intx_kvm()? Thanks,
>>
>> Alex
>>
>>
>>> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
>>> index c38cfd1..c4db407 100644
>>> --- a/hw/virtio/virtio-pci.c
>>> +++ b/hw/virtio/virtio-pci.c
>>> @@ -508,7 +508,7 @@ static int kvm_virtio_pci_irqfd_use(VirtIOPCIProxy
>>> *proxy,
>>> VirtQueue *vq = virtio_get_queue(proxy->vdev, queue_no);
>>> EventNotifier *n = virtio_queue_get_guest_notifier(vq);
>>> int ret;
>>> - ret = kvm_irqchip_add_irqfd_notifier(kvm_state, n, irqfd->virq);
>>> + ret = kvm_irqchip_add_irqfd_notifier(kvm_state, n, NULL, irqfd->virq);
>>> return ret;
>>> }
>>>
>>> diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
>>> index 1e08a85..9e5d78e 100644
>>> --- a/include/sysemu/kvm.h
>>> +++ b/include/sysemu/kvm.h
>>> @@ -309,7 +309,8 @@ int kvm_irqchip_add_msi_route(KVMState *s, MSIMessage
>>> msg);
>>> int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg);
>>> void kvm_irqchip_release_virq(KVMState *s, int virq);
>>>
>>> -int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n, int
>>> virq);
>>> +int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n,
>>> + EventNotifier *rn, int virq);
>>> int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n, int
>>> virq);
>>> void kvm_pc_gsi_handler(void *opaque, int n, int level);
>>> void kvm_pc_setup_irq_routing(bool pci_enabled);
>>> diff --git a/kvm-all.c b/kvm-all.c
>>> index 232c39a..3f69b41 100644
>>> --- a/kvm-all.c
>>> +++ b/kvm-all.c
>>> @@ -1230,7 +1230,8 @@ int kvm_irqchip_update_msi_route(KVMState *s,
>>> int virq, MSIMessage msg)
>>> return kvm_update_routing_entry(s, &kroute);
>>> }
>>>
>>> -static int kvm_irqchip_assign_irqfd(KVMState *s, int fd, int virq, bool
>>> assign)
>>> +static int kvm_irqchip_assign_irqfd(KVMState *s, int fd, int rfd, int virq,
>>> + bool assign)
>>> {
>>> struct kvm_irqfd irqfd = {
>>> .fd = fd,
>>> @@ -1238,6 +1239,11 @@ static int kvm_irqchip_assign_irqfd(KVMState
>>> *s, int fd, int virq, bool assign)
>>> .flags = assign ? 0 : KVM_IRQFD_FLAG_DEASSIGN,
>>> };
>>>
>>> + if (rfd != -1) {
>>> + irqfd.flags |= KVM_IRQFD_FLAG_RESAMPLE;
>>> + irqfd.resamplefd = rfd;
>>> + }
>>> +
>>> if (!kvm_irqfds_enabled()) {
>>> return -ENOSYS;
>>> }
>>> @@ -1276,14 +1282,17 @@ int kvm_irqchip_update_msi_route(KVMState *s,
>>> int virq, MSIMessage msg)
>>> }
>>> #endif /* !KVM_CAP_IRQ_ROUTING */
>>>
>>> -int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n, int virq)
>>> +int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n,
>>> + EventNotifier *rn, int virq)
>>> {
>>> - return kvm_irqchip_assign_irqfd(s, event_notifier_get_fd(n), virq,
>>> true);
>>> + return kvm_irqchip_assign_irqfd(s, event_notifier_get_fd(n),
>>> + rn ? event_notifier_get_fd(rn) : -1, virq, true);
>>> }
>>>
>>> int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n, int
>>> virq)
>>> {
>>> - return kvm_irqchip_assign_irqfd(s, event_notifier_get_fd(n), virq,
>>> false);
>>> + return kvm_irqchip_assign_irqfd(s, event_notifier_get_fd(n), -1, virq,
>>> + false);
>>> }
>>>
>>> static int kvm_irqchip_create(KVMState *s)
>>> --
>>> 1.8.3.3
>>
>>
>>
>>
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