dcache: convert to use new lru list infrastructure

[glommer@openvz.org: don't reintroduce double decrement of nr_unused_dentries, adapted for new LRU return codes]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Glauber Costa <glommer@openvz.org>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/super.c b/fs/super.c
index aa7995d..cd3c2cd 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -79,11 +79,11 @@
 		fs_objects = sb->s_op->nr_cached_objects(sb);
 
 	inodes = list_lru_count(&sb->s_inode_lru);
-	total_objects = sb->s_nr_dentry_unused + inodes + fs_objects + 1;
+	dentries = list_lru_count(&sb->s_dentry_lru);
+	total_objects = dentries + inodes + fs_objects + 1;
 
 	/* proportion the scan between the caches */
-	dentries = mult_frac(sc->nr_to_scan, sb->s_nr_dentry_unused,
-								total_objects);
+	dentries = mult_frac(sc->nr_to_scan, dentries, total_objects);
 	inodes = mult_frac(sc->nr_to_scan, inodes, total_objects);
 
 	/*
@@ -117,7 +117,7 @@
 	if (sb->s_op && sb->s_op->nr_cached_objects)
 		total_objects = sb->s_op->nr_cached_objects(sb);
 
-	total_objects += sb->s_nr_dentry_unused;
+	total_objects += list_lru_count(&sb->s_dentry_lru);
 	total_objects += list_lru_count(&sb->s_inode_lru);
 
 	total_objects = vfs_pressure_ratio(total_objects);
@@ -191,8 +191,7 @@
 		INIT_HLIST_NODE(&s->s_instances);
 		INIT_HLIST_BL_HEAD(&s->s_anon);
 		INIT_LIST_HEAD(&s->s_inodes);
-		INIT_LIST_HEAD(&s->s_dentry_lru);
-		spin_lock_init(&s->s_dentry_lru_lock);
+		list_lru_init(&s->s_dentry_lru);
 		list_lru_init(&s->s_inode_lru);
 		INIT_LIST_HEAD(&s->s_mounts);
 		init_rwsem(&s->s_umount);