diff options
| -rw-r--r-- | drivers/virtio/virtio_pci_common.c | 53 | ||||
| -rw-r--r-- | drivers/virtio/virtio_pci_common.h | 7 |
2 files changed, 51 insertions, 9 deletions
diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index 628f003db79b..cb8bbe6c1a9f 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -46,12 +46,26 @@ bool vp_notify(struct virtqueue *vq) return true; } +/* Notify all slow path virtqueues on an interrupt. */ +static void vp_vring_slow_path_interrupt(int irq, + struct virtio_pci_device *vp_dev) +{ + struct virtio_pci_vq_info *info; + unsigned long flags; + + spin_lock_irqsave(&vp_dev->lock, flags); + list_for_each_entry(info, &vp_dev->slow_virtqueues, node) + vring_interrupt(irq, info->vq); + spin_unlock_irqrestore(&vp_dev->lock, flags); +} + /* Handle a configuration change: Tell driver if it wants to know. */ static irqreturn_t vp_config_changed(int irq, void *opaque) { struct virtio_pci_device *vp_dev = opaque; virtio_config_changed(&vp_dev->vdev); + vp_vring_slow_path_interrupt(irq, vp_dev); return IRQ_HANDLED; } @@ -174,6 +188,11 @@ error: return err; } +static bool vp_is_slow_path_vector(u16 msix_vec) +{ + return msix_vec == VP_MSIX_CONFIG_VECTOR; +} + static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned int index, void (*callback)(struct virtqueue *vq), const char *name, @@ -197,7 +216,10 @@ static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned int in info->vq = vq; if (callback) { spin_lock_irqsave(&vp_dev->lock, flags); - list_add(&info->node, &vp_dev->virtqueues); + if (!vp_is_slow_path_vector(msix_vec)) + list_add(&info->node, &vp_dev->virtqueues); + else + list_add(&info->node, &vp_dev->slow_virtqueues); spin_unlock_irqrestore(&vp_dev->lock, flags); } else { INIT_LIST_HEAD(&info->node); @@ -245,7 +267,8 @@ void vp_del_vqs(struct virtio_device *vdev) if (vp_dev->per_vq_vectors) { int v = vp_dev->vqs[vq->index]->msix_vector; - if (v != VIRTIO_MSI_NO_VECTOR) { + if (v != VIRTIO_MSI_NO_VECTOR && + !vp_is_slow_path_vector(v)) { int irq = pci_irq_vector(vp_dev->pci_dev, v); irq_update_affinity_hint(irq, NULL); @@ -289,13 +312,14 @@ void vp_del_vqs(struct virtio_device *vdev) enum vp_vq_vector_policy { VP_VQ_VECTOR_POLICY_EACH, + VP_VQ_VECTOR_POLICY_SHARED_SLOW, VP_VQ_VECTOR_POLICY_SHARED, }; static struct virtqueue * vp_find_one_vq_msix(struct virtio_device *vdev, int queue_idx, vq_callback_t *callback, const char *name, bool ctx, - int *allocated_vectors, + bool slow_path, int *allocated_vectors, enum vp_vq_vector_policy vector_policy) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); @@ -305,8 +329,13 @@ vp_find_one_vq_msix(struct virtio_device *vdev, int queue_idx, if (!callback) msix_vec = VIRTIO_MSI_NO_VECTOR; - else if (vector_policy == VP_VQ_VECTOR_POLICY_EACH) + else if (vector_policy == VP_VQ_VECTOR_POLICY_EACH || + (vector_policy == VP_VQ_VECTOR_POLICY_SHARED_SLOW && + !slow_path)) msix_vec = (*allocated_vectors)++; + else if (vector_policy != VP_VQ_VECTOR_POLICY_EACH && + slow_path) + msix_vec = VP_MSIX_CONFIG_VECTOR; else msix_vec = VP_MSIX_VQ_VECTOR; vq = vp_setup_vq(vdev, queue_idx, callback, name, ctx, msix_vec); @@ -314,7 +343,8 @@ vp_find_one_vq_msix(struct virtio_device *vdev, int queue_idx, return vq; if (vector_policy == VP_VQ_VECTOR_POLICY_SHARED || - msix_vec == VIRTIO_MSI_NO_VECTOR) + msix_vec == VIRTIO_MSI_NO_VECTOR || + vp_is_slow_path_vector(msix_vec)) return vq; /* allocate per-vq irq if available and necessary */ @@ -374,7 +404,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs, continue; } vqs[i] = vp_find_one_vq_msix(vdev, queue_idx++, vqi->callback, - vqi->name, vqi->ctx, + vqi->name, vqi->ctx, false, &allocated_vectors, vector_policy); if (IS_ERR(vqs[i])) { err = PTR_ERR(vqs[i]); @@ -440,6 +470,13 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs, VP_VQ_VECTOR_POLICY_EACH, desc); if (!err) return 0; + /* Fallback: MSI-X with one shared vector for config and + * slow path queues, one vector per queue for the rest. + */ + err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info, + VP_VQ_VECTOR_POLICY_SHARED_SLOW, desc); + if (!err) + return 0; /* Fallback: MSI-X with one vector for config, one shared for queues. */ err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info, VP_VQ_VECTOR_POLICY_SHARED, desc); @@ -493,7 +530,8 @@ const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index) struct virtio_pci_device *vp_dev = to_vp_device(vdev); if (!vp_dev->per_vq_vectors || - vp_dev->vqs[index]->msix_vector == VIRTIO_MSI_NO_VECTOR) + vp_dev->vqs[index]->msix_vector == VIRTIO_MSI_NO_VECTOR || + vp_is_slow_path_vector(vp_dev->vqs[index]->msix_vector)) return NULL; return pci_irq_get_affinity(vp_dev->pci_dev, @@ -601,6 +639,7 @@ static int virtio_pci_probe(struct pci_dev *pci_dev, vp_dev->vdev.dev.release = virtio_pci_release_dev; vp_dev->pci_dev = pci_dev; INIT_LIST_HEAD(&vp_dev->virtqueues); + INIT_LIST_HEAD(&vp_dev->slow_virtqueues); spin_lock_init(&vp_dev->lock); /* enable the device */ diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h index 3c4bb2d6163a..0cb6fdc8c354 100644 --- a/drivers/virtio/virtio_pci_common.h +++ b/drivers/virtio/virtio_pci_common.h @@ -35,7 +35,7 @@ struct virtio_pci_vq_info { /* the actual virtqueue */ struct virtqueue *vq; - /* the list node for the virtqueues list */ + /* the list node for the virtqueues or slow_virtqueues list */ struct list_head node; /* MSI-X vector (or none) */ @@ -66,9 +66,12 @@ struct virtio_pci_device { /* Where to read and clear interrupt */ u8 __iomem *isr; - /* a list of queues so we can dispatch IRQs */ + /* Lists of queues and potentially slow path queues + * so we can dispatch IRQs. + */ spinlock_t lock; struct list_head virtqueues; + struct list_head slow_virtqueues; /* Array of all virtqueues reported in the * PCI common config num_queues field |