Re: [PATCH 11/13] nvme: switch to use pci_alloc_irq_vectors

From: Christoph Hellwig
Date: Mon Sep 26 2016 - 11:09:11 EST

On Fri, Sep 23, 2016 at 03:21:14PM -0700, Sagi Grimberg wrote:
> Question: is using pci_alloc_irq_vectors() obligated for
> supplying blk-mq with the device affinity mask?

No, but it's very useful. We'll need equivalents for other busses
that provide multipl vectors and vector spreading.

> If I do this completely-untested [1] what will happen?

Everything will be crashing and burning because you call to_pci_dev on
something that's not a PCI dev?

For the next merge window I plan to wire up the affinity information
for the RDMA code, and I will add a counterpart to blk_mq_pci_map_queues
that spreads the queues over the completion vectors.