mm: shmem: change remove_from_page_cache

This patch series changes remove_from_page_cache()'s page ref counting
rule.  Page cache ref count is decreased in delete_from_page_cache().  So
we don't need to decrease the page reference in callers.

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
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/shmem.c b/mm/shmem.c
index 048a95a..8859358 100644 (file)
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1081,7 +1081,7 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc)
        shmem_recalc_inode(inode);
 
        if (swap.val && add_to_swap_cache(page, swap, GFP_ATOMIC) == 0) {
-               remove_from_page_cache(page);
+               delete_from_page_cache(page);
                shmem_swp_set(info, entry, swap.val);
                shmem_swp_unmap(entry);
                if (list_empty(&info->swaplist))
@@ -1091,7 +1091,6 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc)
                spin_unlock(&info->lock);
                swap_shmem_alloc(swap);
                BUG_ON(page_mapped(page));
-               page_cache_release(page);       /* pagecache ref */
                swap_writepage(page, wbc);
                if (inode) {
                        mutex_lock(&shmem_swaplist_mutex);