vfs: skip inodes without pages to free in drop_pagecache_sb()

Many inodes have no pagecache, so we can avoid lots of lock-takings. Signed-off-by: Jan Kara <[email protected]> Cc: Fengguang Wu <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
kyagi · Apr 29, 2008 · af065b8 · af065b8
1 parent eccb95c
commit af065b8
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/fs/drop_caches.c b/fs/drop_caches.c
@@ -20,6 +20,8 @@ static void drop_pagecache_sb(struct super_block *sb)
 	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
 		if (inode->i_state & (I_FREEING|I_WILL_FREE))
 			continue;
+		if (inode->i_mapping->nrpages == 0)
+			continue;
 		__iget(inode);
 		spin_unlock(&inode_lock);
 		__invalidate_mapping_pages(inode->i_mapping, 0, -1, true);