[PATCH 3/3] PCI: vmd: Use managed irq affinities

[Jon Derrick <jonathan.derrick@intel.com>]

Using managed IRQ affinities sets up the VMD affinities identically to
the child devices when those devices vector counts are limited by VMD.
This promotes better affinity handling as interrupts won't necessarily
need to pass context between non-local CPUs. One pre-vector is reserved
for the slow interrupt and not considered in the affinity algorithm.

Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
---
 drivers/pci/controller/vmd.c | 18 +++++-------------
 1 file changed, 5 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index 7aca925..be92076 100644
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -157,22 +157,11 @@ static void vmd_irq_disable(struct irq_data *data)
 	raw_spin_unlock_irqrestore(&list_lock, flags);
 }
 
-/*
- * XXX: Stubbed until we develop acceptable way to not create conflicts with
- * other devices sharing the same vector.
- */
-static int vmd_irq_set_affinity(struct irq_data *data,
-				const struct cpumask *dest, bool force)
-{
-	return -EINVAL;
-}
-
 static struct irq_chip vmd_msi_controller = {
 	.name			= "VMD-MSI",
 	.irq_enable		= vmd_irq_enable,
 	.irq_disable		= vmd_irq_disable,
 	.irq_compose_msi_msg	= vmd_compose_msi_msg,
-	.irq_set_affinity	= vmd_irq_set_affinity,
 };
 
 static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
@@ -722,6 +711,9 @@ static irqreturn_t vmd_irq(int irq, void *data)
 static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
 {
 	struct vmd_dev *vmd;
+	struct irq_affinity affd = {
+		.pre_vectors = 1,
+	};
 	int i, err;
 
 	if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
@@ -749,8 +741,8 @@ 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(dev, 1, vmd->msix_count,
-					PCI_IRQ_MSIX);
+	vmd->msix_count = pci_alloc_irq_vectors_affinity(dev, 1, vmd->msix_count,
+					PCI_IRQ_MSIX | PCI_IRQ_AFFINITY, &affd);
 	if (vmd->msix_count < 0)
 		return vmd->msix_count;
 
-- 
1.8.3.1