thp: fix bad_page to show the real reason the page is bad

page_count shows the count of the head page, but the actual check is done
on the tail page, so show what is really being checked.

Signed-off-by: Andrea Arcangeli <[email protected]>
Acked-by: Rik van Riel <[email protected]>
Acked-by: Mel Gorman <[email protected]>
Reviewed-by: KOSAKI Motohiro <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index c18d1f7cff84d2e4899cc738e81b72ad9e3ff8cc..2a67c3bd403a79a7d739418276840ad939fc0134 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5618,7 +5618,7 @@ void dump_page(struct page *page)
 {
        printk(KERN_ALERT
               "page:%p count:%d mapcount:%d mapping:%p index:%#lx\n",
-               page, page_count(page), page_mapcount(page),
+               page, atomic_read(&page->_count), page_mapcount(page),
                page->mapping, page->index);
        dump_page_flags(page->flags);
 }