On Tue, Feb 15, 2022 at 11:29 AM Zhu, Lingshan <lingshan.zhu at intel.com>
wrote:>
>
>
> On 2/15/2022 11:03 AM, Jason Wang wrote:
> > On Tue, Feb 15, 2022 at 10:18 AM Zhu, Lingshan <lingshan.zhu at
intel.com> wrote:
> >>
> >>
> >> On 2/14/2022 10:27 PM, Michael S. Tsirkin wrote:
> >>> On Mon, Feb 14, 2022 at 06:01:56PM +0800, Zhu Lingshan wrote:
> >>>> On 2/14/2022 3:19 PM, Jason Wang wrote:
> >>>>> ? 2022/2/3 ??3:27, Zhu Lingshan ??:
> >>>>>> On some platforms/devices, there may not be enough
MSI vector
> >>>>>> slots allocated for virtqueues and config changes.
In such a case,
> >>>>>> the interrupt sources(virtqueues, config changes)
must share
> >>>>>> an IRQ/vector, to avoid initialization failures,
keep
> >>>>>> the device functional.
> >>>>>>
> >>>>>> This commit handles three cases:
> >>>>>> (1) number of the allocated vectors == the number
of virtqueues + 1
> >>>>>> (config changes), every virtqueue and the config
interrupt has
> >>>>>> a separated vector/IRQ, the best and the most
likely case.
> >>>>>> (2) number of the allocated vectors is less than
the best case, but
> >>>>>> greater than 1. In this case, all virtqueues share
a vector/IRQ,
> >>>>>> the config interrupt has a separated vector/IRQ
> >>>>>> (3) only one vector is allocated, in this case,
the virtqueues and
> >>>>>> the config interrupt share a vector/IRQ. The worst
and most
> >>>>>> unlikely case.
> >>>>>>
> >>>>>> Otherwise, it needs to fail.
> >>>>>>
> >>>>>> This commit introduces some helper functions:
> >>>>>> ifcvf_set_vq_vector() and
ifcvf_set_config_vector() sets virtqueue
> >>>>>> vector and config vector in the device config
space, so that
> >>>>>> the device can send interrupt DMA.
> >>>>>>
> >>>>>> This commit adds some fields in struct ifcvf_hw
and re-placed
> >>>>>> the existed fields to be aligned with the
cacheline.
> >>>>>>
> >>>>>> Signed-off-by: Zhu Lingshan <lingshan.zhu at
intel.com>
> >>>>>> ---
> >>>>>> drivers/vdpa/ifcvf/ifcvf_base.c | 47 ++++--
> >>>>>> drivers/vdpa/ifcvf/ifcvf_base.h | 23 ++-
> >>>>>> drivers/vdpa/ifcvf/ifcvf_main.c | 243
+++++++++++++++++++++++++++-----
> >>>>>> 3 files changed, 256 insertions(+), 57
deletions(-)
> >>>>>>
> >>>>>> diff --git a/drivers/vdpa/ifcvf/ifcvf_base.c
> >>>>>> b/drivers/vdpa/ifcvf/ifcvf_base.c
> >>>>>> index 397692ae671c..18dcb63ab1e3 100644
> >>>>>> --- a/drivers/vdpa/ifcvf/ifcvf_base.c
> >>>>>> +++ b/drivers/vdpa/ifcvf/ifcvf_base.c
> >>>>>> @@ -15,6 +15,36 @@ struct ifcvf_adapter
*vf_to_adapter(struct
> >>>>>> ifcvf_hw *hw)
> >>>>>> return container_of(hw, struct
ifcvf_adapter, vf);
> >>>>>> }
> >>>>>> +int ifcvf_set_vq_vector(struct ifcvf_hw *hw,
u16 qid, int vector)
> >>>>>> +{
> >>>>>> + struct virtio_pci_common_cfg __iomem *cfg =
hw->common_cfg;
> >>>>>> + struct ifcvf_adapter *ifcvf =
vf_to_adapter(hw);
> >>>>>> +
> >>>>>> + ifc_iowrite16(qid,
&cfg->queue_select);
> >>>>>> + ifc_iowrite16(vector,
&cfg->queue_msix_vector);
> >>>>>> + if
(ifc_ioread16(&cfg->queue_msix_vector) => >>>>>>
VIRTIO_MSI_NO_VECTOR) {
> >>>>>> + IFCVF_ERR(ifcvf->pdev, "No msix
vector for queue %u\n", qid);
> >>>>>> + return -EINVAL;
> >>>>>> + }
> >>>>> Let's leave this check for the caller, E.g can
caller try to assign
> >>>>> NO_VECTOR during uni-nit?
> >>>> ifcvf driver sets NO_VECTOR when call hw_disable(). I am
not sure whether I
> >>>> get it,
> > I meant you invent the ifcvf_set_vq_vector() you'd better use that
in
> > hw_disable() as well.
> OK
> >
> >>>> Yes we can let the caller check a vq vector, however this
may cause more
> >>>> than three levels brackets, may looks ugly.
> > I don't understand here, this is how virito_pci did:
> >
> > /*
> > * vp_modern_queue_vector - set the MSIX vector for a specific
virtqueue
> > * @mdev: the modern virtio-pci device
> > * @index: queue index
> > * @vector: the config vector
> > *
> > * Returns the config vector read from the device
> > */
> > u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev,
> > u16 index, u16 vector)
> > {
> > struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
> >
> > vp_iowrite16(index, &cfg->queue_select);
> > vp_iowrite16(vector, &cfg->queue_msix_vector);
> > /* Flush the write out to device */
> > return vp_ioread16(&cfg->queue_msix_vector);
> > }
> > EXPORT_SYMBOL_GPL(vp_modern_queue_vector);
> I mean if we leave the checks for the caller, it may look like:
> + for (i = 0; i < vf->nr_vring; i++) {
> + snprintf(vf->vring[i].msix_name, 256,
"ifcvf[%s]-%d\n",
> pci_name(pdev), i);
> + vector = i;
> + irq = pci_irq_vector(pdev, vector);
> + ret = devm_request_irq(&pdev->dev, irq,
> + ifcvf_intr_handler, 0,
> + vf->vring[i].msix_name,
> + &vf->vring[i]);
> + if (ret) {
> + IFCVF_ERR(pdev, "Failed to request irq for vq
> %d\n", i);
> + ifcvf_free_vq_irq(adapter, i);
> + } else {
> + vf->vring[i].irq = irq;
> + ifcvf_set_vq_vector(vf, i, vector);
> if (xxxxx) {
> xxxxxxxxxxx;
> }
> + }
> + }
If the brackets are the only concern, you can factor out the per vq
logic into a dedicated function.
Thanks
>
> Too many brackets.
> >
> >>>>>> +
> >>>>>> + return 0;
> >>>>>> +}
> >>>>>> +
> >>>>>> +int ifcvf_set_config_vector(struct ifcvf_hw *hw,
int vector)
> >>>>>> +{
> >>>>>> + struct virtio_pci_common_cfg __iomem *cfg =
hw->common_cfg;
> >>>>>> + struct ifcvf_adapter *ifcvf =
vf_to_adapter(hw);
> >>>>>> +
> >>>>>> + cfg = hw->common_cfg;
> >>>>>> + ifc_iowrite16(vector,
&cfg->msix_config);
> >>>>>> + if (ifc_ioread16(&cfg->msix_config) ==
VIRTIO_MSI_NO_VECTOR) {
> >>>>>> + IFCVF_ERR(ifcvf->pdev, "No msix
vector for device config\n");
> >>>>>> + return -EINVAL;
> >>>>>> + }
> >>>>> Similar question as above.
> >>>>>
> >>>>>
> >>>>>> +
> >>>>>> + return 0;
> >>>>>> +}
> >>>>>> +
> >>>>>> static void __iomem *get_cap_addr(struct
ifcvf_hw *hw,
> >>>>>> struct virtio_pci_cap *cap)
> >>>>>> {
> >>>>>> @@ -140,6 +170,8 @@ int ifcvf_init_hw(struct
ifcvf_hw *hw, struct
> >>>>>> pci_dev *pdev)
> >>>>>> hw->common_cfg,
hw->notify_base, hw->isr,
> >>>>>> hw->dev_cfg,
hw->notify_off_multiplier);
> >>>>>> + hw->vqs_shared_irq = -EINVAL;
> >>>>>> +
> >>>>>> return 0;
> >>>>>> }
> >>>>>> @@ -321,12 +353,6 @@ static int
ifcvf_hw_enable(struct ifcvf_hw *hw)
> >>>>>> ifcvf = vf_to_adapter(hw);
> >>>>>> cfg = hw->common_cfg;
> >>>>>> - ifc_iowrite16(IFCVF_MSI_CONFIG_OFF,
&cfg->msix_config);
> >>>>>> -
> >>>>>> - if (ifc_ioread16(&cfg->msix_config) ==
VIRTIO_MSI_NO_VECTOR) {
> >>>>>> - IFCVF_ERR(ifcvf->pdev, "No msix
vector for device config\n");
> >>>>>> - return -EINVAL;
> >>>>>> - }
> >>>>>> for (i = 0; i < hw->nr_vring; i++)
{
> >>>>>> if (!hw->vring[i].ready)
> >>>>>> @@ -340,15 +366,6 @@ static int
ifcvf_hw_enable(struct ifcvf_hw *hw)
> >>>>>>
ifc_iowrite64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
> >>>>>>
&cfg->queue_used_hi);
> >>>>>> ifc_iowrite16(hw->vring[i].size,
&cfg->queue_size);
> >>>>>> - ifc_iowrite16(i + IFCVF_MSI_QUEUE_OFF,
> >>>>>> &cfg->queue_msix_vector);
> >>>>>> -
> >>>>>> - if
(ifc_ioread16(&cfg->queue_msix_vector) => >>>>>> -
VIRTIO_MSI_NO_VECTOR) {
> >>>>>> - IFCVF_ERR(ifcvf->pdev,
> >>>>>> - "No msix vector for queue
%u\n", i);
> >>>>>> - return -EINVAL;
> >>>>>> - }
> >>>>>> -
> >>>>>> ifcvf_set_vq_state(hw, i,
hw->vring[i].last_avail_idx);
> >>>>>> ifc_iowrite16(1,
&cfg->queue_enable);
> >>>>>> }
> >>>>>> diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h
> >>>>>> b/drivers/vdpa/ifcvf/ifcvf_base.h
> >>>>>> index 949b4fb9d554..9cfe088c82e9 100644
> >>>>>> --- a/drivers/vdpa/ifcvf/ifcvf_base.h
> >>>>>> +++ b/drivers/vdpa/ifcvf/ifcvf_base.h
> >>>>>> @@ -27,8 +27,6 @@
> >>>>>> #define IFCVF_QUEUE_ALIGNMENT PAGE_SIZE
> >>>>>> #define IFCVF_QUEUE_MAX 32768
> >>>>>> -#define IFCVF_MSI_CONFIG_OFF 0
> >>>>>> -#define IFCVF_MSI_QUEUE_OFF 1
> >>>>>> #define IFCVF_PCI_MAX_RESOURCE 6
> >>>>>> #define IFCVF_LM_CFG_SIZE 0x40
> >>>>>> @@ -42,6 +40,13 @@
> >>>>>> #define ifcvf_private_to_vf(adapter) \
> >>>>>> (&((struct ifcvf_adapter
*)adapter)->vf)
> >>>>>> +/* all vqs and config interrupt has its own
vector */
> >>>>>> +#define MSIX_VECTOR_PER_VQ_AND_CONFIG 1
> >>>>>> +/* all vqs share a vector, and config interrupt
has a separate
> >>>>>> vector */
> >>>>>> +#define MSIX_VECTOR_SHARED_VQ_AND_CONFIG 2
> >>>>>> +/* all vqs and config interrupt share a vector */
> >>>>>> +#define MSIX_VECTOR_DEV_SHARED 3
> >>>>> I think there's no much value to differ 2 from 3
consider config
> >>>>> interrupt should be rare.
> >>>> IMHO we still need 2 and 3, because
MSIX_VECTOR_SHARED_VQ_AND_CONFIG means
> >>>> there are at least 2 vectors,
> >>>> the vqs share one vector, config change has its own
vector.
> > I want to know the value of having a dedicated vector for config?
> I think a dedicated vector for config changes can help us avoid
> operations on config space when vq interrupt triggered.
> >
> >>>> MSIX_VECTOR_DEV_SHARED means three are only one vector,
all vqs and config
> >>>> changes need to share this vector.
> >>>>>
> >>>>>> +
> >>>>>> static inline u8 ifc_ioread8(u8 __iomem *addr)
> >>>>>> {
> >>>>>> return ioread8(addr);
> >>>>>> @@ -97,25 +102,27 @@ struct ifcvf_hw {
> >>>>>> u8 __iomem *isr;
> >>>>>> /* Live migration */
> >>>>>> u8 __iomem *lm_cfg;
> >>>>>> - u16 nr_vring;
> >>>>> Any reason for moving nv_vring, config_size, and other
stuffs?
> >>>> for cacheline alignment.
> >>> maybe a separate patch then.
> >> Sure
> >>
> >> Thanks!
> >>>>>
> >>>>>> /* Notification bar number */
> >>>>>> u8 notify_bar;
> >>>>>> + u8 msix_vector_status;
> >>>>>> + /* virtio-net or virtio-blk device config
size */
> >>>>>> + u32 config_size;
> >>>>>> /* Notificaiton bar address */
> >>>>>> void __iomem *notify_base;
> >>>>>> phys_addr_t notify_base_pa;
> >>>>>> u32 notify_off_multiplier;
> >>>>>> + u32 dev_type;
> >>>>>> u64 req_features;
> >>>>>> u64 hw_features;
> >>>>>> - u32 dev_type;
> >>>>>> struct virtio_pci_common_cfg __iomem
*common_cfg;
> >>>>>> void __iomem *dev_cfg;
> >>>>>> struct vring_info vring[IFCVF_MAX_QUEUES];
> >>>>>> void __iomem * const *base;
> >>>>>> char config_msix_name[256];
> >>>>>> struct vdpa_callback config_cb;
> >>>>>> - unsigned int config_irq;
> >>>>>> - /* virtio-net or virtio-blk device config
size */
> >>>>>> - u32 config_size;
> >>>>>> + int config_irq;
> >>>>>> + int vqs_shared_irq;
> >>>>>> + u16 nr_vring;
> >>>>>> };
> >>>>>> struct ifcvf_adapter {
> >>>>>> @@ -160,4 +167,6 @@ int ifcvf_set_vq_state(struct
ifcvf_hw *hw, u16
> >>>>>> qid, u16 num);
> >>>>>> struct ifcvf_adapter *vf_to_adapter(struct
ifcvf_hw *hw);
> >>>>>> int ifcvf_probed_virtio_net(struct ifcvf_hw
*hw);
> >>>>>> u32 ifcvf_get_config_size(struct ifcvf_hw
*hw);
> >>>>>> +int ifcvf_set_vq_vector(struct ifcvf_hw *hw, u16
qid, int vector);
> >>>>>> +int ifcvf_set_config_vector(struct ifcvf_hw *hw,
int vector);
> >>>>>> #endif /* _IFCVF_H_ */
> >>>>>> diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c
> >>>>>> b/drivers/vdpa/ifcvf/ifcvf_main.c
> >>>>>> index 44c89ab0b6da..ca414399f040 100644
> >>>>>> --- a/drivers/vdpa/ifcvf/ifcvf_main.c
> >>>>>> +++ b/drivers/vdpa/ifcvf/ifcvf_main.c
> >>>>>> @@ -17,6 +17,7 @@
> >>>>>> #define DRIVER_AUTHOR "Intel
Corporation"
> >>>>>> #define IFCVF_DRIVER_NAME
"ifcvf"
> >>>>>> +/* handles config interrupt */
> >>>>> This seems unrelated to the shared IRQ logic and it
looks useless since
> >>>>> it's easily to deduce it from the function name
below.
> >>>> OK, do you mean the comments? I can remove these comments.
> > Yes.
> >
> >>>>>> static irqreturn_t ifcvf_config_changed(int
irq, void *arg)
> >>>>>> {
> >>>>>> struct ifcvf_hw *vf = arg;
> >>>>>> @@ -27,6 +28,7 @@ static irqreturn_t
ifcvf_config_changed(int irq,
> >>>>>> void *arg)
> >>>>>> return IRQ_HANDLED;
> >>>>>> }
> >>>>>> +/* handles vqs interrupt */
> >>>>> So did this.
> >>>>>
> >>>>>
> >>>>>> static irqreturn_t ifcvf_intr_handler(int irq,
void *arg)
> >>>>>> {
> >>>>>> struct vring_info *vring = arg;
> >>>>>> @@ -37,24 +39,78 @@ static irqreturn_t
ifcvf_intr_handler(int irq,
> >>>>>> void *arg)
> >>>>>> return IRQ_HANDLED;
> >>>>>> }
> >>>>>> +/* handls vqs shared interrupt */
> >>>>>> +static irqreturn_t
ifcvf_vq_shared_intr_handler(int irq, void *arg)
> >>>>>> +{
> >>>>>> + struct ifcvf_hw *vf = arg;
> >>>>>> + struct vring_info *vring;
> >>>>>> + int i;
> >>>>>> +
> >>>>>> + for (i = 0; i < vf->nr_vring; i++) {
> >>>>>> + vring = &vf->vring[i];
> >>>>>> + if (vring->cb.callback)
> >>>>>> +
vf->vring->cb.callback(vring->cb.private);
> >>>>>> + }
> >>>>>> +
> >>>>>> + return IRQ_HANDLED;
> >>>>>> +}
> >>>>>> +
> >>>>>> +/* handles a shared interrupt for vqs and config
*/
> >>>>>> +static irqreturn_t
ifcvf_dev_shared_intr_handler(int irq, void *arg)
> >>>>>> +{
> >>>>>> + struct ifcvf_hw *vf = arg;
> >>>>>> + u8 isr;
> >>>>>> +
> >>>>>> + isr = ifc_ioread8(vf->isr);
> >>>>> We need to exactly what vp_interrupt do here. Checking
against vf->isr
> >>>>> first and return IRQ_NONE if it is not set.
> >>>>>
> >>>>> Always return IRQ_HANDLED will break the device who
shares an irq with
> >>>>> IFCVF.
> >>>> as we discussed in another thread(spec inconsistency about
ISR), ISR may
> >>>> only works for INTx for now,
> >>>> but VFs don't have INTx, and a VF may not share its
vectors with other
> >>>> devices, so I guess it can work
> >>>> and may be our best try for now.
> > Right, I thought you're using shared irq but actually not.
> >
> >>>>>> + if (isr & VIRTIO_PCI_ISR_CONFIG)
> >>>>>> + ifcvf_config_changed(irq, arg);
> > I wonder how ISR works in IFCVF, if ISR doesn't work for MSI, we
need
> > to remove the check of isr otherwise we will break config interrupt?
> >
> >>>>>> +
> >>>>>> + return ifcvf_vq_shared_intr_handler(irq,
arg);
> >>>>>> +}
> >>>>>> +
> >>>>>> static void ifcvf_free_irq_vectors(void *data)
> >>>>>> {
> >>>>>> pci_free_irq_vectors(data);
> >>>>>> }
> >>>>>> -static void ifcvf_free_irq(struct
ifcvf_adapter *adapter, int queues)
> >>>>>> +static void ifcvf_free_vq_irq(struct
ifcvf_adapter *adapter, int
> >>>>>> queues)
> >>>>>> {
> >>>>>> struct pci_dev *pdev = adapter->pdev;
> >>>>>> struct ifcvf_hw *vf = &adapter->vf;
> >>>>>> int i;
> >>>>>> + if (vf->msix_vector_status ==
MSIX_VECTOR_PER_VQ_AND_CONFIG) {
> >>>>>> + for (i = 0; i < queues; i++) {
> >>>>>> + devm_free_irq(&pdev->dev,
vf->vring[i].irq, &vf->vring[i]);
> >>>>>> + vf->vring[i].irq = -EINVAL;
> >>>>>> + }
> >>>>>> + } else {
> >>>>>> + devm_free_irq(&pdev->dev,
vf->vqs_shared_irq, vf);
> >>>>>> + vf->vqs_shared_irq = -EINVAL;
> >>>>>> + }
> >>>>>> +}
> >>>>>> - for (i = 0; i < queues; i++) {
> >>>>>> - devm_free_irq(&pdev->dev,
vf->vring[i].irq, &vf->vring[i]);
> >>>>>> - vf->vring[i].irq = -EINVAL;
> >>>>>> +static void ifcvf_free_config_irq(struct
ifcvf_adapter *adapter)
> >>>>>> +{
> >>>>>> + struct pci_dev *pdev = adapter->pdev;
> >>>>>> + struct ifcvf_hw *vf = &adapter->vf;
> >>>>>> +
> >>>>>> + /* If the irq is shared by all vqs and the
config interrupt,
> >>>>>> + * it is already freed in ifcvf_free_vq_irq,
so here only
> >>>>>> + * need to free config irq when
msix_vector_status !> >>>>>> MSIX_VECTOR_DEV_SHARED
> >>>>>> + */
> >>>>>> + if (vf->msix_vector_status !=
MSIX_VECTOR_DEV_SHARED) {
> >>>>>> + devm_free_irq(&pdev->dev,
vf->config_irq, vf);
> >>>>>> + vf->config_irq = -EINVAL;
> >>>>>> }
> >>>>>> +}
> >>>>>> +
> >>>>>> +static void ifcvf_free_irq(struct ifcvf_adapter
*adapter, int queues)
> >>>>>> +{
> >>>>>> + struct pci_dev *pdev = adapter->pdev;
> >>>>>> - devm_free_irq(&pdev->dev,
vf->config_irq, vf);
> >>>>>> + ifcvf_free_vq_irq(adapter, queues);
> >>>>>> + ifcvf_free_config_irq(adapter);
> >>>>>> ifcvf_free_irq_vectors(pdev);
> >>>>>> }
> >>>>>> @@ -86,58 +142,172 @@ static int
ifcvf_alloc_vectors(struct
> >>>>>> ifcvf_adapter *adapter)
> >>>>>> return ret;
> >>>>>> }
> >>>>>> -static int ifcvf_request_irq(struct
ifcvf_adapter *adapter)
> >>>>>> +static int ifcvf_request_per_vq_irq(struct
ifcvf_adapter *adapter)
> >>>>>> {
> >>>>>> struct pci_dev *pdev = adapter->pdev;
> >>>>>> struct ifcvf_hw *vf = &adapter->vf;
> >>>>>> - int vector, nvectors, i, ret, irq;
> >>>>>> - u16 max_intr;
> >>>>>> + int i, vector, ret, irq;
> >>>>>> - nvectors = ifcvf_alloc_vectors(adapter);
> >>>>>> - if (!(nvectors > 0))
> >>>>>> - return nvectors;
> >>>>>> + for (i = 0; i < vf->nr_vring; i++) {
> >>>>>> + snprintf(vf->vring[i].msix_name, 256,
"ifcvf[%s]-%d\n",
> >>>>>> pci_name(pdev), i);
> >>>>>> + vector = i;
> >>>>>> + irq = pci_irq_vector(pdev, vector);
> >>>>>> + ret = devm_request_irq(&pdev->dev,
irq,
> >>>>>> + ifcvf_intr_handler, 0,
> >>>>>> + vf->vring[i].msix_name,
> >>>>>> + &vf->vring[i]);
> >>>>>> + if (ret) {
> >>>>>> + IFCVF_ERR(pdev, "Failed to
request irq for vq %d\n", i);
> >>>>>> + ifcvf_free_vq_irq(adapter, i);
> >>>>>> + } else {
> >>>>>> + vf->vring[i].irq = irq;
> >>>>>> + ifcvf_set_vq_vector(vf, i, vector);
> >>>>>> + }
> >>>>>> + }
> >>>>>> - max_intr = vf->nr_vring + 1;
> >>>>>> + vf->vqs_shared_irq = -EINVAL;
> >>>>>> +
> >>>>>> + return 0;
> >>>>>> +}
> >>>>>> +
> >>>>>> +static int ifcvf_request_shared_vq_irq(struct
ifcvf_adapter *adapter)
> >>>>>> +{
> >>>>>> + struct pci_dev *pdev = adapter->pdev;
> >>>>>> + struct ifcvf_hw *vf = &adapter->vf;
> >>>>>> + int i, vector, ret, irq;
> >>>>>> +
> >>>>>> + vector = 0;
> >>>>>> + /* reuse msix_name[256] space of vring0 to
store shared vqs
> >>>>>> interrupt name */
> >>>>> I think we can remove this comment since the code is
straightforward.
> >>>> sure
> >>>>>> + snprintf(vf->vring[0].msix_name, 256,
> >>>>>> "ifcvf[%s]-vqs-shared-irq\n",
pci_name(pdev));
> >>>>>> + irq = pci_irq_vector(pdev, vector);
> >>>>>> + ret = devm_request_irq(&pdev->dev,
irq,
> >>>>>> + ifcvf_vq_shared_intr_handler,
0,
> >>>>>> + vf->vring[0].msix_name,
vf);
> >>>>>> + if (ret) {
> >>>>>> + IFCVF_ERR(pdev, "Failed to request
shared irq for vf\n");
> >>>>>> +
> >>>>>> + return ret;
> >>>>>> + }
> >>>>>> +
> >>>>>> + vf->vqs_shared_irq = irq;
> >>>>>> + for (i = 0; i < vf->nr_vring; i++) {
> >>>>>> + vf->vring[i].irq = -EINVAL;
> >>>>>> + ifcvf_set_vq_vector(vf, i, vector);
> >>>>>> + }
> >>>>>> +
> >>>>>> + return 0;
> >>>>>> +
> >>>>>> +}
> >>>>>> +
> >>>>>> +static int ifcvf_request_dev_shared_irq(struct
ifcvf_adapter *adapter)
> >>>>>> +{
> >>>>>> + struct pci_dev *pdev = adapter->pdev;
> >>>>>> + struct ifcvf_hw *vf = &adapter->vf;
> >>>>>> + int i, vector, ret, irq;
> >>>>>> +
> >>>>>> + vector = 0;
> >>>>>> + /* reuse msix_name[256] space of vring0 to
store shared device
> >>>>>> interrupt name */
> >>>>>> + snprintf(vf->vring[0].msix_name, 256,
> >>>>>> "ifcvf[%s]-dev-shared-irq\n",
pci_name(pdev));
> >>>>>> + irq = pci_irq_vector(pdev, vector);
> >>>>>> + ret = devm_request_irq(&pdev->dev,
irq,
> >>>>>> + ifcvf_dev_shared_intr_handler,
0,
> >>>>>> + vf->vring[0].msix_name,
vf);
> >>>>>> + if (ret) {
> >>>>>> + IFCVF_ERR(pdev, "Failed to request
shared irq for vf\n");
> >>>>>> - ret = pci_alloc_irq_vectors(pdev,
max_intr,
> >>>>>> - max_intr, PCI_IRQ_MSIX);
> >>>>>> - if (ret < 0) {
> >>>>>> - IFCVF_ERR(pdev, "Failed to alloc IRQ
vectors\n");
> >>>>>> return ret;
> >>>>>> }
> >>>>>> + vf->vqs_shared_irq = irq;
> >>>>>> + for (i = 0; i < vf->nr_vring; i++) {
> >>>>>> + vf->vring[i].irq = -EINVAL;
> >>>>>> + ifcvf_set_vq_vector(vf, i, vector);
> >>>>>> + }
> >>>>>> +
> >>>>>> + vf->config_irq = irq;
> >>>>>> + ifcvf_set_config_vector(vf, vector);
> >>>>>> +
> >>>>>> + return 0;
> >>>>>> +
> >>>>>> +}
> >>>>>> +
> >>>>>> +static int ifcvf_request_vq_irq(struct
ifcvf_adapter *adapter)
> >>>>>> +{
> >>>>>> + struct ifcvf_hw *vf = &adapter->vf;
> >>>>>> + int ret;
> >>>>>> +
> >>>>>> + if (vf->msix_vector_status ==
MSIX_VECTOR_PER_VQ_AND_CONFIG)
> >>>>>> + ret = ifcvf_request_per_vq_irq(adapter);
> >>>>>> + else
> >>>>>> + ret =
ifcvf_request_shared_vq_irq(adapter);
> >>>>>> +
> >>>>>> + return ret;
> >>>>>> +}
> >>>>>> +
> >>>>>> +static int ifcvf_request_config_irq(struct
ifcvf_adapter *adapter)
> >>>>>> +{
> >>>>>> + struct pci_dev *pdev = adapter->pdev;
> >>>>>> + struct ifcvf_hw *vf = &adapter->vf;
> >>>>>> + int config_vector, ret;
> >>>>>> +
> >>>>>> + if (vf->msix_vector_status ==
MSIX_VECTOR_DEV_SHARED)
> >>>>>> + return 0;
> >>>>>> +
> >>>>>> + if (vf->msix_vector_status ==
MSIX_VECTOR_PER_VQ_AND_CONFIG)
> >>>>>> + /* vector 0 ~ vf->nr_vring for vqs,
num vf->nr_vring vector
> >>>>>> for config interrupt */
> >>>>>> + config_vector = vf->nr_vring;
> >>>>>> +
> >>>>>> + if (vf->msix_vector_status ==
MSIX_VECTOR_SHARED_VQ_AND_CONFIG)
> >>>>>> + /* vector 0 for vqs and 1 for config
interrupt */
> >>>>>> + config_vector = 1;
> >>>>>> +
> >>>>>> snprintf(vf->config_msix_name, 256,
"ifcvf[%s]-config\n",
> >>>>>> pci_name(pdev));
> >>>>>> - vector = 0;
> >>>>>> - vf->config_irq = pci_irq_vector(pdev,
vector);
> >>>>>> + vf->config_irq = pci_irq_vector(pdev,
config_vector);
> >>>>>> ret = devm_request_irq(&pdev->dev,
vf->config_irq,
> >>>>>> ifcvf_config_changed, 0,
> >>>>>> vf->config_msix_name,
vf);
> >>>>>> if (ret) {
> >>>>>> IFCVF_ERR(pdev, "Failed to
request config irq\n");
> >>>>>> + ifcvf_free_vq_irq(adapter,
vf->nr_vring);
> >>>>>> return ret;
> >>>>>> }
> >>>>>> - for (i = 0; i < vf->nr_vring; i++)
{
> >>>>>> - snprintf(vf->vring[i].msix_name, 256,
"ifcvf[%s]-%d\n",
> >>>>>> - pci_name(pdev), i);
> >>>>>> - vector = i + IFCVF_MSI_QUEUE_OFF;
> >>>>>> - irq = pci_irq_vector(pdev, vector);
> >>>>>> - ret = devm_request_irq(&pdev->dev,
irq,
> >>>>>> - ifcvf_intr_handler, 0,
> >>>>>> - vf->vring[i].msix_name,
> >>>>>> - &vf->vring[i]);
> >>>>>> - if (ret) {
> >>>>>> - IFCVF_ERR(pdev,
> >>>>>> - "Failed to request irq for
vq %d\n", i);
> >>>>>> - ifcvf_free_irq(adapter, i);
> >>>>>> + ifcvf_set_config_vector(vf, config_vector);
> >>>>>> - return ret;
> >>>>>> - }
> >>>>>> + return 0;
> >>>>>> +}
> >>>>>> +
> >>>>>> +static int ifcvf_request_irq(struct ifcvf_adapter
*adapter)
> >>>>>> +{
> >>>>> As replied above, I think having two modes should be
sufficient and the
> >>>>> code could be greatly simplified.
> >>>> Do you mean if we don't get enough vectors, just use
only one vector for the
> >>>> vqs and config changes? I guess this
> >>>> only works if ISR work for MSIX as we expects, or we may
waste some time in
> >>>> the device config space.
> > Ok, I think I got you here. It's better to document this in the
change log.
> >
> > Thanks
> >
> >>>> Thanks,
> >>>> Zhu Lingshan
> >>>>> Thanks
> >>>>>
> >>>>>
> >>>>>> + struct ifcvf_hw *vf = &adapter->vf;
> >>>>>> + int nvectors, ret, max_intr;
> >>>>>> - vf->vring[i].irq = irq;
> >>>>>> + nvectors = ifcvf_alloc_vectors(adapter);
> >>>>>> + if (!(nvectors > 0))
> >>>>>> + return nvectors;
> >>>>>> +
> >>>>>> + vf->msix_vector_status =
MSIX_VECTOR_PER_VQ_AND_CONFIG;
> >>>>>> + max_intr = vf->nr_vring + 1;
> >>>>>> + if (nvectors < max_intr)
> >>>>>> + vf->msix_vector_status =
MSIX_VECTOR_SHARED_VQ_AND_CONFIG;
> >>>>>> +
> >>>>>> + if (nvectors == 1) {
> >>>>>> + vf->msix_vector_status =
MSIX_VECTOR_DEV_SHARED;
> >>>>>> + ret =
ifcvf_request_dev_shared_irq(adapter);
> >>>>>> +
> >>>>>> + return ret;
> >>>>>> }
> >>>>>> + ret = ifcvf_request_vq_irq(adapter);
> >>>>>> + if (ret)
> >>>>>> + return ret;
> >>>>>> +
> >>>>>> + ret = ifcvf_request_config_irq(adapter);
> >>>>>> +
> >>>>>> + if (ret)
> >>>>>> + return ret;
> >>>>>> +
> >>>>>> return 0;
> >>>>>> }
> >>>>>> @@ -441,7 +611,10 @@ static int
ifcvf_vdpa_get_vq_irq(struct
> >>>>>> vdpa_device *vdpa_dev,
> >>>>>> {
> >>>>>> struct ifcvf_hw *vf =
vdpa_to_vf(vdpa_dev);
> >>>>>> - return vf->vring[qid].irq;
> >>>>>> + if (vf->vqs_shared_irq < 0)
> >>>>>> + return vf->vring[qid].irq;
> >>>>>> + else
> >>>>>> + return -EINVAL;
> >>>>>> }
> >>>>>> static struct vdpa_notification_area
> >>>>>> ifcvf_get_vq_notification(struct vdpa_device
*vdpa_dev,
> >>>>> _______________________________________________
> >>>>> Virtualization mailing list
> >>>>> Virtualization at lists.linux-foundation.org
> >>>>>
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
>