On 8/30/20 7:23 PM, Wei Yang wrote: > Function dequeue_huge_page_node_exact() iterates the free list and > return the first valid free hpage. > > Instead of break and check the loop variant, we could return in the loop > directly. This could reduce some redundant check. > > Signed-off-by: Wei Yang <richard.weiy...@linux.alibaba.com> > --- > mm/hugetlb.c | 20 ++++++++------------ > 1 file changed, 8 insertions(+), 12 deletions(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 7b3357c1dcec..709be7ab65af 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1040,21 +1040,17 @@ static struct page > *dequeue_huge_page_node_exact(struct hstate *h, int nid) > if (nocma && is_migrate_cma_page(page)) > continue; > > - if (!PageHWPoison(page)) > + if (PageHWPoison(page)) > break;
Previously, when encountering a PageHWPoison(page) the loop would continue and check the next page in the list. It now breaks the loop and returns NULL. Is not this a change in behavior? Perhaps you want to change that break to a continue. Or, restructure in some other way. -- Mike Kravetz > + > + list_move(&page->lru, &h->hugepage_activelist); > + set_page_refcounted(page); > + h->free_huge_pages--; > + h->free_huge_pages_node[nid]--; > + return page; > } > > - /* > - * if 'non-isolated free hugepage' not found on the list, > - * the allocation fails. > - */ > - if (&h->hugepage_freelists[nid] == &page->lru) > - return NULL; > - list_move(&page->lru, &h->hugepage_activelist); > - set_page_refcounted(page); > - h->free_huge_pages--; > - h->free_huge_pages_node[nid]--; > - return page; > + return NULL; > } > > static struct page *dequeue_huge_page_nodemask(struct hstate *h, gfp_t > gfp_mask, int nid, >
