On Fri, Jan 04, 2019 at 03:21:07PM +0800, Ming Lei wrote: > Thinking about the patch further: after pci_alloc_irq_vectors_affinity() > is returned, queue number for non-polled queues can't be changed at will, > because we have to make sure to spread all CPUs on each queue type, and > the mapping has been fixed by pci_alloc_irq_vectors_affinity() already. > > So looks the approach in this patch may be wrong. That's a bit of a problem, and not a new one. We always had to allocate vectors before creating IRQ driven CQ's, but the vector affinity is created before we know if the queue-pair can be created. Should the queue creation fail, there may be CPUs that don't have a queue. Does this mean the pci msi API is wrong? It seems like we'd need to initially allocate vectors without PCI_IRQ_AFFINITY, then have the kernel set affinity only after completing the queue-pair setup.
