[PATCH 7/8] pci: spread interrupt vectors in pci_alloc_irq_vectors

Christoph Hellwig
2016-04-16T01:36:04Z

Set the affinity_mask before allocating vectors. And for now we also
need a little hack after allocation, hopefully someone smarter than me
can move this into the core code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/pci/irq.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/irq.c b/drivers/pci/irq.c
index b683465..d26df69 100644
--- a/drivers/pci/irq.c
+++ b/drivers/pci/irq.c
@@ -55,9 +55,14 @@ int pci_alloc_irq_vectors(struct pci_dev *pdev, int nr_vecs)

nr_vecs = min(nr_vecs, pci_nr_irq_vectors(pdev));

+ ret = irq_create_affinity_mask(&pdev->dev.irq_affinity, nr_vecs);
+ if (ret)
+ return ret;
+
+ ret = -ENOMEM;
irqs = kcalloc(nr_vecs, sizeof(u32), GFP_KERNEL);
if (!irqs)
- return -ENOMEM;
+ goto out_free_affinity;

vecs = pci_enable_msix_range_wrapper(pdev, irqs, nr_vecs);
if (vecs <= 0) {
@@ -75,11 +80,20 @@ int pci_alloc_irq_vectors(struct pci_dev *pdev, int nr_vecs)
irqs[i] = pdev->irq + i;
}

+ /* XXX: this should really move into the core IRQ allocation code.. */
+ if (vecs > 1) {
+ for (i = 0; i < vecs; i++)
+ irq_program_affinity(irqs[i]);
+ }
+
pdev->irqs = irqs;
return vecs;

out_free_irqs:
kfree(irqs);
+out_free_affinity:
+ kfree(pdev->dev.irq_affinity);
+ pdev->dev.irq_affinity = NULL;
return ret;
}
EXPORT_SYMBOL(pci_alloc_irq_vectors);
--
2.1.4