On Wed, Aug 30, 2017 at 04:41:39PM -0500, Bjorn Helgaas wrote: > I added some breadcrumbs to the changelog about this connection > between affinity and limiting the number of IRQs. Did I get this > right? > > This is on pci/host-vmd for v4.14. Awesome, sounds good to me! > commit be85af02e1b00d49cd678d8f2ea6f391bdbaca19 > Author: Keith Busch <keith.busch@xxxxxxxxx> > Date: Wed Aug 30 12:15:04 2017 -0400 > > 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@xxxxxxxx> > Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx> > [bhelgaas: add irq_calc_affinity_vectors() reference to changelog] > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
