mm/thp: fix node page state in split_huge_page_to_list()

Make sure split_huge_page_to_list() handles the state of shmem THP and
file THP properly.

Link: http://lkml.kernel.org/r/20191017164223.2762148-3-songliubraving@fb.com
Fixes: 60fbf0ab5da1 ("mm,thp: stats for file backed THP")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Tested-by: Song Liu <songliubraving@fb.com>
Acked-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index c5cb6dc..13cc937 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2789,8 +2789,13 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
                        ds_queue->split_queue_len--;
                        list_del(page_deferred_list(head));
                }
-               if (mapping)
-                       __dec_node_page_state(page, NR_SHMEM_THPS);
+               if (mapping) {
+                       if (PageSwapBacked(page))
+                               __dec_node_page_state(page, NR_SHMEM_THPS);
+                       else
+                               __dec_node_page_state(page, NR_FILE_THPS);
+               }
+
                spin_unlock(&ds_queue->split_queue_lock);
                __split_huge_page(page, list, end, flags);
                if (PageSwapCache(head)) {