On Tue 03-08-21 13:59:20, Feng Tang wrote: > From: Ben Widawsky <ben.widawsky@xxxxxxxxx> > > Implement the missing huge page allocation functionality while obeying > the preferred node semantics. This is similar to the implementation > for general page allocation, as it uses a fallback mechanism to try > multiple preferred nodes first, and then all other nodes. > > [akpm: fix compling issue when merging with other hugetlb patch] > [Thanks to 0day bot for catching the missing #ifdef CONFIG_NUMA issue] > Link: https://lore.kernel.org/r/20200630212517.308045-12-ben.widawsky@xxxxxxxxx > Suggested-by: Michal Hocko <mhocko@xxxxxxxx> > Signed-off-by: Ben Widawsky <ben.widawsky@xxxxxxxxx> > Co-developed-by: Feng Tang <feng.tang@xxxxxxxxx> > Signed-off-by: Feng Tang <feng.tang@xxxxxxxxx> ifdefery is just ugly as hell. One way to get rid of that would be to provide a mpol_is_preferred_many() wrapper and hide the CONFIG_NUMA in mempolicy.h. I haven't checked but this might help to remove some other ifdefery as well. I especially dislike the label hidden in the ifdef. You can get rid of that by checking the page for NULL. > --- > mm/hugetlb.c | 28 ++++++++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 95714fb28150..9279f6d478d9 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1166,7 +1166,20 @@ static struct page *dequeue_huge_page_vma(struct hstate *h, > > gfp_mask = htlb_alloc_mask(h); > nid = huge_node(vma, address, gfp_mask, &mpol, &nodemask); > +#ifdef CONFIG_NUMA > + if (mpol->mode == MPOL_PREFERRED_MANY) { > + page = dequeue_huge_page_nodemask(h, gfp_mask, nid, nodemask); > + if (page) > + goto check_reserve; > + /* Fallback to all nodes */ > + nodemask = NULL; > + } > +#endif > page = dequeue_huge_page_nodemask(h, gfp_mask, nid, nodemask); > + > +#ifdef CONFIG_NUMA > +check_reserve: > +#endif > if (page && !avoid_reserve && vma_has_reserves(vma, chg)) { > SetHPageRestoreReserve(page); > h->resv_huge_pages--; > @@ -2147,6 +2160,21 @@ struct page *alloc_buddy_huge_page_with_mpol(struct hstate *h, > nodemask_t *nodemask; > > nid = huge_node(vma, addr, gfp_mask, &mpol, &nodemask); > +#ifdef CONFIG_NUMA > + if (mpol->mode == MPOL_PREFERRED_MANY) { > + gfp_t gfp = gfp_mask | __GFP_NOWARN; > + > + gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL); > + page = alloc_surplus_huge_page(h, gfp, nid, nodemask, false); > + if (page) { > + mpol_cond_put(mpol); > + return page; > + } > + > + /* Fallback to all nodes */ > + nodemask = NULL; > + } > +#endif > page = alloc_surplus_huge_page(h, gfp_mask, nid, nodemask, false); > mpol_cond_put(mpol); > > -- > 2.14.1 -- Michal Hocko SUSE Labs
