diff options
| -rw-r--r-- | mm/page_alloc.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index b5a58d476c1a..d73bfad1c32f 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -847,8 +847,19 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order, struct page *page = __rmqueue(zone, order, migratetype); if (unlikely(page == NULL)) break; + + /* + * Split buddy pages returned by expand() are received here + * in physical page order. The page is added to the callers and + * list and the list head then moves forward. From the callers + * perspective, the linked list is ordered by page number in + * some conditions. This is useful for IO devices that can + * merge IO requests if the physical pages are ordered + * properly. + */ list_add(&page->lru, list); set_page_private(page, migratetype); + list = &page->lru; } spin_unlock(&zone->lock); return i; |