On Thu, 7 Apr 2016, Michal Hocko wrote:
> > +static void hugetlb_cgroup_init(struct hugetlb_cgroup *h_cgroup,
> > + struct hugetlb_cgroup *parent_h_cgroup)
> > +{
> > + int idx;
> > +
> > + for (idx = 0; idx < HUGE_MAX_HSTATE; idx++) {
> > + struct page_counter *counter = &h_cgroup->hugepage[idx];
> > + struct page_counter *parent = NULL;
> > + unsigned long limit;
> > + int ret;
> > +
> > + if (parent_h_cgroup)
> > + parent = &parent_h_cgroup->hugepage[idx];
> > + page_counter_init(counter, parent);
> > +
> > + limit = round_down(PAGE_COUNTER_MAX,
> > + 1 << huge_page_order(&hstates[idx]));
> > + ret = page_counter_limit(counter, limit);
> > + VM_BUG_ON(ret);
> > + }
> > +}
>
> I fail to see the point for this. Why would want to round down
> PAGE_COUNTER_MAX? It will never make a real difference. Or am I missing
> something?
Did you try the patch?
If we're rounding down the user value, it makes sense to be consistent
with the upper bound default to specify intent.
