Re: [PATCH v6 4/6] mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY

[Michal Hocko]

On Wed 21-07-21 13:49:15, Mike Kravetz wrote:
> On 7/12/21 1:09 AM, Feng Tang wrote:
[...]
> > +#ifdef CONFIG_NUMA
> > +	if (mpol->mode == MPOL_PREFERRED_MANY) {
> > +		gfp_t gfp = (gfp_mask | __GFP_NOWARN) & ~__GFP_DIRECT_RECLAIM;
> 
> I believe __GFP_NOWARN will be added later in alloc_buddy_huge_page, so
> no need to add here?

The mask is manipulated here anyway and the __GFP_NOWARN is really
telling that there is no need to report the failure for _this_
allocation request. alloc_surplus_huge_page might alter that in whatever
way in the future. So I would keep NOWARN here for the code clarity
rather than rely on some implicit assumption down the path.
-- 
Michal Hocko
SUSE Labs