On Mon, Feb 25, 2019 at 11:30 PM Dave Hansen [off-list ref] wrote:

On 2/24/19 4:34 AM, Pingfan Liu wrote:

quoted

At present the node to cpumask map is set up until the secondary
cpu boot up. But it is too late for the purpose of building node fall back
list at early boot stage. Considering that init_cpu_to_node() already owns
cpu to node map, it is a good place to set up node to cpumask map too. So
do it by calling numa_add_cpu(cpu) in init_cpu_to_node().

It sounds like you have carefully considered the ordering and
dependencies here.  However, none of that consideration has made it into
the code.

Could you please add some comments to the new call-sites to explain why
the *must* be where they are?

OK. How about: "building up node fallback list needs cpumask info, so
filling cpumask info here"
Thanks for your kindly review.

Regards,
Pingfan