Re: [PATCH v4 07/13] mm/mempolicy: handle MPOL_PREFERRED_MANY like BIND

[Michal Hocko]

On Wed 17-03-21 11:40:04, Feng Tang wrote:
> From: Ben Widawsky <ben.widawsky@xxxxxxxxx>
> 
> Begin the real plumbing for handling this new policy. Now that the
> internal representation for preferred nodes and bound nodes is the same,
> and we can envision what multiple preferred nodes will behave like,
> there are obvious places where we can simply reuse the bind behavior.
> 
> In v1 of this series, the moral equivalent was:
> "mm: Finish handling MPOL_PREFERRED_MANY". Like that, this attempts to
> implement the easiest spots for the new policy. Unlike that, this just
> reuses BIND.

No, this is a bug step back. I think we really want to treat this as
PREFERRED. It doesn't have much to do with the BIND semantic at all.
At this stage there should be 2 things remaining - syscalls plumbing and
2 pass allocation request (optimistic preferred nodes restricted and
fallback to all nodes).
-- 
Michal Hocko
SUSE Labs