From: Yuxue Liu <yuxue.liu@xxxxxxxxxxxxxxx> When there is a ctlq and it doesn't require interrupt callbacks,the original method of calculating vectors wastes hardware MSI or MSI-X resources as well as system IRQ resources. Referencing the per_vq_vectors mode in the vp_find_vqs_msix function, calculate the required number of vectors based on whether the callback is set. Signed-off-by: Yuxue Liu <yuxue.liu@xxxxxxxxxxxxxxx> --- V1 -> V2: fix when allocating IRQs, scan all queues. V1: https://lore.kernel.org/all/20240318030121.1873-1-gavin.liu@xxxxxxxxxxxxxxx/ --- drivers/vdpa/virtio_pci/vp_vdpa.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c index 281287fae89f..87329d4358ce 100644 --- a/drivers/vdpa/virtio_pci/vp_vdpa.c +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c @@ -160,8 +160,15 @@ static int vp_vdpa_request_irq(struct vp_vdpa *vp_vdpa) struct pci_dev *pdev = mdev->pci_dev; int i, ret, irq; int queues = vp_vdpa->queues; - int vectors = queues + 1; + int allocated_vectors, vectors = 0; + u16 msix_vec; + for (i = 0; i < queues; i++) { + if (vp_vdpa->vring[i].cb.callback != NULL) + vectors++; + } + /*By default, config interrupts request a single vector*/ + vectors = vectors + 1; ret = pci_alloc_irq_vectors(pdev, vectors, vectors, PCI_IRQ_MSIX); if (ret != vectors) { dev_err(&pdev->dev, @@ -169,13 +176,17 @@ static int vp_vdpa_request_irq(struct vp_vdpa *vp_vdpa) vectors, ret); return ret; } - vp_vdpa->vectors = vectors; for (i = 0; i < queues; i++) { + if (vp_vdpa->vring[i].cb.callback == NULL) + continue; + else + msix_vec = allocated_vectors++; + snprintf(vp_vdpa->vring[i].msix_name, VP_VDPA_NAME_SIZE, "vp-vdpa[%s]-%d\n", pci_name(pdev), i); - irq = pci_irq_vector(pdev, i); + irq = pci_irq_vector(pdev, msix_vec); ret = devm_request_irq(&pdev->dev, irq, vp_vdpa_vq_handler, 0, vp_vdpa->vring[i].msix_name, @@ -185,13 +196,14 @@ static int vp_vdpa_request_irq(struct vp_vdpa *vp_vdpa) "vp_vdpa: fail to request irq for vq %d\n", i); goto err; } - vp_modern_queue_vector(mdev, i, i); + vp_modern_queue_vector(mdev, i, msix_vec); vp_vdpa->vring[i].irq = irq; } + msix_vec = allocated_vectors; snprintf(vp_vdpa->msix_name, VP_VDPA_NAME_SIZE, "vp-vdpa[%s]-config\n", pci_name(pdev)); - irq = pci_irq_vector(pdev, queues); + irq = pci_irq_vector(pdev, msix_vec); ret = devm_request_irq(&pdev->dev, irq, vp_vdpa_config_handler, 0, vp_vdpa->msix_name, vp_vdpa); if (ret) { @@ -199,7 +211,7 @@ static int vp_vdpa_request_irq(struct vp_vdpa *vp_vdpa) "vp_vdpa: fail to request irq for vq %d\n", i); goto err; } - vp_modern_config_vector(mdev, queues); + vp_modern_config_vector(mdev, msix_vec); vp_vdpa->config_irq = irq; return 0; -- 2.43.0