On 5/19/2021 6:38 PM, Alex Williamson wrote:
> On Fri, 7 May 2021 05:25:09 -0700
> Steve Sistare <steven.sist...@oracle.com> wrote:
>
>> Export vfio_address_spaces and vfio_listener_skipped_section.
>> Add optional eventfd arg to vfio_add_kvm_msi_virq.
>> Refactor vector use into a helper vfio_vector_init.
>> All for use by cpr in a subsequent patch. No functional change.
>>
>> Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
>> ---
>> hw/vfio/common.c | 4 ++--
>> hw/vfio/pci.c | 36 +++++++++++++++++++++++++-----------
>> include/hw/vfio/vfio-common.h | 3 +++
>> 3 files changed, 30 insertions(+), 13 deletions(-)
>>
>> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
>> index ae5654f..9220e64 100644
>> --- a/hw/vfio/common.c
>> +++ b/hw/vfio/common.c
>> @@ -42,7 +42,7 @@
>>
>> VFIOGroupList vfio_group_list =
>> QLIST_HEAD_INITIALIZER(vfio_group_list);
>> -static QLIST_HEAD(, VFIOAddressSpace) vfio_address_spaces =
>> +VFIOAddressSpaceList vfio_address_spaces =
>> QLIST_HEAD_INITIALIZER(vfio_address_spaces);
>>
>> #ifdef CONFIG_KVM
>> @@ -534,7 +534,7 @@ static int vfio_host_win_del(VFIOContainer *container,
>> hwaddr min_iova,
>> return -1;
>> }
>>
>> -static bool vfio_listener_skipped_section(MemoryRegionSection *section)
>> +bool vfio_listener_skipped_section(MemoryRegionSection *section)
>> {
>> return (!memory_region_is_ram(section->mr) &&
>> !memory_region_is_iommu(section->mr)) ||
>> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
>> index 5c65aa0..7a4fb6c 100644
>> --- a/hw/vfio/pci.c
>> +++ b/hw/vfio/pci.c
>> @@ -411,7 +411,7 @@ static int vfio_enable_vectors(VFIOPCIDevice *vdev, bool
>> msix)
>> }
>>
>> static void vfio_add_kvm_msi_virq(VFIOPCIDevice *vdev, VFIOMSIVector
>> *vector,
>> - int vector_n, bool msix)
>> + int vector_n, bool msix, int eventfd)
>> {
>> int virq;
>>
>> @@ -419,7 +419,9 @@ static void vfio_add_kvm_msi_virq(VFIOPCIDevice *vdev,
>> VFIOMSIVector *vector,
>> return;
>> }
>>
>> - if (event_notifier_init(&vector->kvm_interrupt, 0)) {
>> + if (eventfd >= 0) {
>> + event_notifier_init_fd(&vector->kvm_interrupt, eventfd);
>> + } else if (event_notifier_init(&vector->kvm_interrupt, 0)) {
>> return;
>> }
>
> This seems very obfuscated. The "active" arg of event_notifier_init()
> just seems to preload the eventfd with a signal. What does that have
> to do with an eventfd arg to this function? What if the first branch
> returns failure?
Perhaps you mis-read the code? The function called in the first branch is
different than
the function called in the second branch. And event_notifier_init_fd is void
and never fails.
Eschew obfuscation.
Gesundheit.
>> @@ -455,6 +457,22 @@ static void vfio_update_kvm_msi_virq(VFIOMSIVector
>> *vector, MSIMessage msg,
>> kvm_irqchip_commit_routes(kvm_state);
>> }
>>
>> +static void vfio_vector_init(VFIOPCIDevice *vdev, int nr, int eventfd)
>> +{
>> + VFIOMSIVector *vector = &vdev->msi_vectors[nr];
>> + PCIDevice *pdev = &vdev->pdev;
>> +
>> + vector->vdev = vdev;
>> + vector->virq = -1;
>> + if (eventfd >= 0) {
>> + event_notifier_init_fd(&vector->interrupt, eventfd);
>> + } else if (event_notifier_init(&vector->interrupt, 0)) {
>> + error_report("vfio: Error: event_notifier_init failed");
>> + }
>
> Gak, here's that same pattern.
>
>> + vector->use = true;
>> + msix_vector_use(pdev, nr);
>> +}
>> +
>> static int vfio_msix_vector_do_use(PCIDevice *pdev, unsigned int nr,
>> MSIMessage *msg, IOHandler *handler)
>> {
>> @@ -466,14 +484,10 @@ static int vfio_msix_vector_do_use(PCIDevice *pdev,
>> unsigned int nr,
>>
>> vector = &vdev->msi_vectors[nr];
>>
>> + vfio_vector_init(vdev, nr, -1);
>> +
>> if (!vector->use) {
>> - vector->vdev = vdev;
>> - vector->virq = -1;
>> - if (event_notifier_init(&vector->interrupt, 0)) {
>> - error_report("vfio: Error: event_notifier_init failed");
>> - }
>> - vector->use = true;
>> - msix_vector_use(pdev, nr);
>> + vfio_vector_init(vdev, nr, -1);
>> }
>
> Huh? That's not at all "no functional change". Also the branch is
> entirely dead code now.
Good catch, thank you. This is a rebase error. The unconditional call to
vfio_vector_init
should not be there. With that fix, we have:
if (!vector->use) {
vfio_vector_init(vdev, nr, -1);
}
and there is no functional change; the actions performed in vfio_vector_init
are identical to
those deleted here.
>> qemu_set_fd_handler(event_notifier_get_fd(&vector->interrupt),
>> @@ -491,7 +505,7 @@ static int vfio_msix_vector_do_use(PCIDevice *pdev,
>> unsigned int nr,
>> }
>> } else {
>> if (msg) {
>> - vfio_add_kvm_msi_virq(vdev, vector, nr, true);
>> + vfio_add_kvm_msi_virq(vdev, vector, nr, true, -1);
>> }
>> }
>>
>> @@ -641,7 +655,7 @@ retry:
>> * Attempt to enable route through KVM irqchip,
>> * default to userspace handling if unavailable.
>> */
>> - vfio_add_kvm_msi_virq(vdev, vector, i, false);
>> + vfio_add_kvm_msi_virq(vdev, vector, i, false, -1);
>> }
>
> And then we're not really passing an eventfd anyway :-\ I'm so
> confused...
This patch just adds the eventfd arg. The next few patches pass valid
eventfd's from the
cpr code paths.
- Steve
>> /* Set interrupt type prior to possible interrupts */
>> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
>> index 6141162..00acb85 100644
>> --- a/include/hw/vfio/vfio-common.h
>> +++ b/include/hw/vfio/vfio-common.h
>> @@ -204,6 +204,8 @@ int vfio_get_device(VFIOGroup *group, const char *name,
>> extern const MemoryRegionOps vfio_region_ops;
>> typedef QLIST_HEAD(VFIOGroupList, VFIOGroup) VFIOGroupList;
>> extern VFIOGroupList vfio_group_list;
>> +typedef QLIST_HEAD(, VFIOAddressSpace) VFIOAddressSpaceList;
>> +extern VFIOAddressSpaceList vfio_address_spaces;
>>
>> bool vfio_mig_active(void);
>> int64_t vfio_mig_bytes_transferred(void);
>> @@ -222,6 +224,7 @@ struct vfio_info_cap_header *
>> vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id);
>> #endif
>> extern const MemoryListener vfio_prereg_listener;
>> +bool vfio_listener_skipped_section(MemoryRegionSection *section);
>>
>> int vfio_spapr_create_window(VFIOContainer *container,
>> MemoryRegionSection *section,
>
