Commit 46a6561b authored Aug 30, 2017 by Keith Busch Committed by Bjorn Helgaas Aug 30, 2017

PCI: vmd: Remove IRQ affinity so we can allocate more IRQs



VMD hardware has to share its vectors among child devices in its PCI
domain so we should allocate as many as possible rather than just ones
that can be affinitized.

pci_alloc_irq_vectors_affinity() limits the number of affinitized IRQs to
the number of present CPUs (see irq_calc_affinity_vectors()).  But we'd
prefer to have more vectors, even if they aren't distributed across the
CPUs, so use pci_alloc_irq_vectors() instead.

Reported-by: Brad Goodman <Bradley.Goodman@dell.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
[bhelgaas: add irq_calc_affinity_vectors() reference to changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

parent e2b1820b

drivers/pci/host/vmd.c

+2 −10

Original line number	Diff line number	Diff line
		@@ -671,14 +671,6 @@ static int vmd_probe(struct pci_dev dev, const struct pci_device_id id)
		struct vmd_dev *vmd;
		int i, err;

		/*
		* The first vector is reserved for special use, so start affinity at
		* the second vector
		*/
		struct irq_affinity affd = {
		.pre_vectors = 1,
		};

		if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
		return -ENOMEM;

		@@ -704,8 +696,8 @@ static int vmd_probe(struct pci_dev dev, const struct pci_device_id id)
		if (vmd->msix_count < 0)
		return -ENODEV;

		vmd->msix_count = pci_alloc_irq_vectors_affinity(dev, 1, vmd->msix_count,
		PCI_IRQ_MSIX \| PCI_IRQ_AFFINITY, &affd);
		vmd->msix_count = pci_alloc_irq_vectors(dev, 1, vmd->msix_count,
		PCI_IRQ_MSIX);
		if (vmd->msix_count < 0)
		return vmd->msix_count;

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