Re: [PATCH v3 4/5] genirq/affinity: allow driver's discontigous affinity set

From: Ming Lei
Date: Mon Jun 24 2019 - 22:15:03 EST

Hi Thomas,

On Mon, Jun 24, 2019 at 05:42:39PM +0200, Thomas Gleixner wrote:
> On Mon, 24 Jun 2019, Weiping Zhang wrote:
> > The driver may implement multiple affinity set, and some of
> > are empty, for this case we just skip them.
> Why? What's the point of creating empty sets? Just because is not a real
> good justification.

Patch 5 will add 4 new sets for supporting NVMe's weighted round robin
arbitration. It can be a headache to manage so many irq sets(now the total
sets can become 6) dynamically since size of anyone in the new 4 sets can
be zero, so each particular set is assigned one static index for avoiding
the management trouble, then empty set will be seen by

So looks skipping the empty set makes sense because the API will become
easier to use than before.