On 2/14/2022 3:19 PM, Jason Wang wrote:
ifcvf driver sets NO_VECTOR when call hw_disable(). I am not sure whether I get it, Yes we can let the caller check a vq vector, however this may cause more than three levels brackets, may looks ugly.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.cindex 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?
IMHO we still need 2 and 3, because MSIX_VECTOR_SHARED_VQ_AND_CONFIG means there are at least 2 vectors,+ + 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.hindex 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 3I think there's no much value to differ 2 from 3 consider config interrupt should be rare.
the vqs share one vector, config change has its own vector.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.
/* 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.cindex 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.
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 workstatic 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.
and may be our best try for now.
+ 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.
sure
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.+ 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, 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@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
_______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
