From 18863d3a3f593f47b075b9f53ebf9228dc76cf72 Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Wed, 3 May 2017 14:54:04 -0700 Subject: [PATCH] mm: remove SWAP_DIRTY in ttu If we found lazyfree page is dirty, try_to_unmap_one can just SetPageSwapBakced in there like PG_mlocked page and just return with SWAP_FAIL which is very natural because the page is not swappable right now so that vmscan can activate it. There is no point to introduce new return value SWAP_DIRTY in try_to_unmap at the moment. Link: http://lkml.kernel.org/r/1489555493-14659-3-git-send-email-minchan@kernel.org Signed-off-by: Minchan Kim Acked-by: Hillf Danton Acked-by: Kirill A. Shutemov Cc: Anshuman Khandual Cc: Johannes Weiner Cc: Michal Hocko Cc: Naoya Horiguchi Cc: Vlastimil Babka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/rmap.h | 1 - mm/rmap.c | 4 ++-- mm/vmscan.c | 3 --- 3 files changed, 2 insertions(+), 6 deletions(-) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index fee10d744ebd..b556eefa62bc 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -298,6 +298,5 @@ static inline int page_mkclean(struct page *page) #define SWAP_AGAIN 1 #define SWAP_FAIL 2 #define SWAP_MLOCK 3 -#define SWAP_DIRTY 4 #endif /* _LINUX_RMAP_H */ diff --git a/mm/rmap.c b/mm/rmap.c index 4baf504e4213..f6aa18d8a420 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1436,7 +1436,8 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, * discarded. Remap the page to page table. */ set_pte_at(mm, address, pvmw.pte, pteval); - ret = SWAP_DIRTY; + SetPageSwapBacked(page); + ret = SWAP_FAIL; page_vma_mapped_walk_done(&pvmw); break; } @@ -1506,7 +1507,6 @@ static int page_mapcount_is_zero(struct page *page) * SWAP_AGAIN - we missed a mapping, try again later * SWAP_FAIL - the page is unswappable * SWAP_MLOCK - page is mlocked. - * SWAP_DIRTY - page is dirty MADV_FREE page */ int try_to_unmap(struct page *page, enum ttu_flags flags) { diff --git a/mm/vmscan.c b/mm/vmscan.c index e54c882d6789..f1fd388454bd 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1147,9 +1147,6 @@ static unsigned long shrink_page_list(struct list_head *page_list, if (page_mapped(page)) { switch (ret = try_to_unmap(page, ttu_flags | TTU_BATCH_FLUSH)) { - case SWAP_DIRTY: - SetPageSwapBacked(page); - /* fall through */ case SWAP_FAIL: nr_unmap_fail++; goto activate_locked; -- 2.20.1