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 <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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);
 }