[Patch v2 6/7] mm/hugetlb: return non-isolated page in the loop instead of break and check

From: Wei Yang
Date: Thu Aug 27 2020 - 23:33:11 EST


Function dequeue_huge_page_node_exact() iterates the free list and
return the first non-isolated one.

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.weiyang@xxxxxxxxxxxxxxxxx>
Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
---
mm/hugetlb.c | 26 ++++++++++++--------------
1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5a71cb7acf6b..6ad365dd1e96 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1033,20 +1033,18 @@ static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid)
{
struct page *page;

- list_for_each_entry(page, &h->hugepage_freelists[nid], lru)
- if (!PageHWPoison(page))
- break;
- /*
- * 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;
+ list_for_each_entry(page, &h->hugepage_freelists[nid], lru) {
+ if (PageHWPoison(page))
+ continue;
+
+ 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,
--
2.20.1 (Apple Git-117)