在 2022/2/3 下午3:27, Zhu Lingshan 写道:
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@xxxxxxxxx>
---
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?
+
+ 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.
+
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?
/* 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.
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.
+ if (isr & VIRTIO_PCI_ISR_CONFIG)
+ ifcvf_config_changed(irq, arg);
+
+ 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.
+ 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.
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@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
