We don't have to add a freeable page into lru and then remove from it. This change saves a couple of actions and makes the moving more clear. The SetPageLRU needs to be kept here for list intergrity. Otherwise: #0 mave_pages_to_lru #1 release_pages if (put_page_testzero()) if (put_page_testzero()) !PageLRU //skip lru_lock list_add(&page->lru,); else list_add(&page->lru,) //corrupt Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: yun.wang@xxxxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx --- mm/vmscan.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 572fb17c6273..8719361b47a0 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1852,26 +1852,18 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, while (!list_empty(list)) { page = lru_to_page(list); VM_BUG_ON_PAGE(PageLRU(page), page); + list_del(&page->lru); if (unlikely(!page_evictable(page))) { - list_del(&page->lru); spin_unlock_irq(&pgdat->lru_lock); putback_lru_page(page); spin_lock_irq(&pgdat->lru_lock); continue; } - lruvec = mem_cgroup_page_lruvec(page, pgdat); - SetPageLRU(page); - lru = page_lru(page); - - nr_pages = hpage_nr_pages(page); - update_lru_size(lruvec, lru, page_zonenum(page), nr_pages); - list_move(&page->lru, &lruvec->lists[lru]); if (put_page_testzero(page)) { __ClearPageLRU(page); __ClearPageActive(page); - del_page_from_lru_list(page, lruvec, lru); if (unlikely(PageCompound(page))) { spin_unlock_irq(&pgdat->lru_lock); @@ -1880,6 +1872,12 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, } else list_add(&page->lru, &pages_to_free); } else { + lruvec = mem_cgroup_page_lruvec(page, pgdat); + lru = page_lru(page); + nr_pages = hpage_nr_pages(page); + + update_lru_size(lruvec, lru, page_zonenum(page), nr_pages); + list_add(&page->lru, &lruvec->lists[lru]); nr_moved += nr_pages; } } -- 1.8.3.1