From 9c2053040ca7ae52f1143a47ae84502aa7970438 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Mon, 20 Jun 2016 09:39:53 -0600 Subject: [PATCH] x86/PCI: VMD: Separate MSI and MSI-X vector sharing Child devices in a VMD domain that want to use MSI are slowing down MSI-X using devices sharing the same vectors. Move all MSI usage to a single VMD vector, and MSI-X devices can share the rest. Signed-off-by: Keith Busch Signed-off-by: Bjorn Helgaas Acked-by: Jon Derrick --- arch/x86/pci/vmd.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/x86/pci/vmd.c b/arch/x86/pci/vmd.c index 0f77cc1dbb4e..fd582abfad91 100644 --- a/arch/x86/pci/vmd.c +++ b/arch/x86/pci/vmd.c @@ -169,11 +169,14 @@ static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info, * XXX: We can be even smarter selecting the best IRQ once we solve the * affinity problem. */ -static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd) +static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc) { - int i, best = 0; + int i, best = 1; unsigned long flags; + if (!desc->msi_attrib.is_msix || vmd->msix_count == 1) + return &vmd->irqs[0]; + raw_spin_lock_irqsave(&list_lock, flags); for (i = 1; i < vmd->msix_count; i++) if (vmd->irqs[i].count < vmd->irqs[best].count) @@ -188,14 +191,15 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info, unsigned int virq, irq_hw_number_t hwirq, msi_alloc_info_t *arg) { - struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(arg->desc)->bus); + struct msi_desc *desc = arg->desc; + struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus); struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL); if (!vmdirq) return -ENOMEM; INIT_LIST_HEAD(&vmdirq->node); - vmdirq->irq = vmd_next_irq(vmd); + vmdirq->irq = vmd_next_irq(vmd, desc); vmdirq->virq = virq; irq_domain_set_info(domain, virq, vmdirq->irq->vmd_vector, info->chip, -- 2.20.1