There are a few places the code assumes anonymous pages should have
SwapBacked flag set. MADV_FREE pages are anonymous pages but we are
going to add them to LRU_INACTIVE_FILE list and clear SwapBacked flag
for them. The assumption doesn't hold any more, so fix them.
Cc: Michal Hocko <mho...@suse.com>
Cc: Minchan Kim <minc...@kernel.org>
Cc: Hugh Dickins <hu...@google.com>
Cc: Rik van Riel <r...@redhat.com>
Cc: Mel Gorman <mgor...@techsingularity.net>
Cc: Andrew Morton <a...@linux-foundation.org>
Acked-by: Johannes Weiner <han...@cmpxchg.org>
Signed-off-by: Shaohua Li <s...@fb.com>
---
mm/huge_memory.c | 1 -
mm/khugepaged.c | 8 +++-----
mm/migrate.c | 3 ++-
mm/rmap.c | 3 ++-
4 files changed, 7 insertions(+), 8 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 7dda8d6..cf9fb46 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2361,7 +2361,6 @@ int split_huge_page_to_list(struct page *page, struct
list_head *list)
VM_BUG_ON_PAGE(is_huge_zero_page(page), page);
VM_BUG_ON_PAGE(!PageLocked(page), page);
- VM_BUG_ON_PAGE(!PageSwapBacked(page), page);
VM_BUG_ON_PAGE(!PageCompound(page), page);
if (PageAnon(head)) {
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 34bce5c..a4b499f 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -481,8 +481,7 @@ void __khugepaged_exit(struct mm_struct *mm)
static void release_pte_page(struct page *page)
{
- /* 0 stands for page_is_file_cache(page) == false */
- dec_node_page_state(page, NR_ISOLATED_ANON + 0);
+ dec_node_page_state(page, NR_ISOLATED_ANON + page_is_file_cache(page));
unlock_page(page);
putback_lru_page(page);
}
@@ -530,7 +529,6 @@ static int __collapse_huge_page_isolate(struct
vm_area_struct *vma,
VM_BUG_ON_PAGE(PageCompound(page), page);
VM_BUG_ON_PAGE(!PageAnon(page), page);
- VM_BUG_ON_PAGE(!PageSwapBacked(page), page);
/*
* We can do it before isolate_lru_page because the
@@ -577,8 +575,8 @@ static int __collapse_huge_page_isolate(struct
vm_area_struct *vma,
result = SCAN_DEL_PAGE_LRU;
goto out;
}
- /* 0 stands for page_is_file_cache(page) == false */
- inc_node_page_state(page, NR_ISOLATED_ANON + 0);
+ inc_node_page_state(page,
+ NR_ISOLATED_ANON + page_is_file_cache(page));
VM_BUG_ON_PAGE(!PageLocked(page), page);
VM_BUG_ON_PAGE(PageLRU(page), page);
diff --git a/mm/migrate.c b/mm/migrate.c
index 2c63ac0..7c8df1f 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1943,7 +1943,8 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
/* Prepare a page as a migration target */
__SetPageLocked(new_page);
- __SetPageSwapBacked(new_page);
+ if (PageSwapBacked(page))
+ __SetPageSwapBacked(new_page);
/* anon mapping, we can simply copy page->mapping to the new page: */
new_page->mapping = page->mapping;
diff --git a/mm/rmap.c b/mm/rmap.c
index 96eb85c..c621088 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1416,7 +1416,8 @@ static int try_to_unmap_one(struct page *page, struct
vm_area_struct *vma,
* Store the swap location in the pte.
* See handle_pte_fault() ...
*/
- VM_BUG_ON_PAGE(!PageSwapCache(page), page);
+ VM_BUG_ON_PAGE(!PageSwapCache(page) &&
PageSwapBacked(page),
+ page);
if (!PageDirty(page)) {
/* It's a freeable page by MADV_FREE */
--
2.9.3
