list_lru: dynamically adjust node arrays

We currently use a compile-time constant to size the node array for the
list_lru structure.  Due to this, we don't need to allocate any memory at
initialization time.  But as a consequence, the structures that contain
embedded list_lru lists can become way too big (the superblock for
instance contains two of them).

This patch aims at ameliorating this situation by dynamically allocating
the node arrays with the firmware provided nr_node_ids.

Signed-off-by: Glauber Costa <glommer@openvz.org>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
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>

3 files changed, 22 insertions, 5 deletions

diff --git a/fs/super.c b/fs/super.c
index 0f9ae0c94fae..ddc5a94221c5 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -201,8 +201,12 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags)
 		INIT_HLIST_NODE(&s->s_instances);
 		INIT_HLIST_BL_HEAD(&s->s_anon);
 		INIT_LIST_HEAD(&s->s_inodes);
-		list_lru_init(&s->s_dentry_lru);
-		list_lru_init(&s->s_inode_lru);
+
+		if (list_lru_init(&s->s_dentry_lru))
+			goto err_out;
+		if (list_lru_init(&s->s_inode_lru))
+			goto err_out_dentry_lru;
+
 		INIT_LIST_HEAD(&s->s_mounts);
 		init_rwsem(&s->s_umount);
 		lockdep_set_class(&s->s_umount, &type->s_umount_key);
@@ -242,6 +246,9 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags)
 	}
 out:
 	return s;
+
+err_out_dentry_lru:
+	list_lru_destroy(&s->s_dentry_lru);
 err_out:
 	security_sb_free(s);
 #ifdef CONFIG_SMP
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 2f9a8866b52b..2cbb1dedfeb4 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -1592,6 +1592,7 @@ xfs_free_buftarg(
 	struct xfs_mount	*mp,
 	struct xfs_buftarg	*btp)
 {
+	list_lru_destroy(&btp->bt_lru);
 	unregister_shrinker(&btp->bt_shrinker);
 
 	if (mp->m_flags & XFS_MOUNT_BARRIER)
@@ -1666,9 +1667,12 @@ xfs_alloc_buftarg(
 	if (!btp->bt_bdi)
 		goto error;
 
-	list_lru_init(&btp->bt_lru);
 	if (xfs_setsize_buftarg_early(btp, bdev))
 		goto error;
+
+	if (list_lru_init(&btp->bt_lru))
+		goto error;
+
 	btp->bt_shrinker.count_objects = xfs_buftarg_shrink_count;
 	btp->bt_shrinker.scan_objects = xfs_buftarg_shrink_scan;
 	btp->bt_shrinker.seeks = DEFAULT_SEEKS;
diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
index c53c88f2733f..9fa916a69218 100644
--- a/fs/xfs/xfs_qm.c
+++ b/fs/xfs/xfs_qm.c
@@ -831,11 +831,18 @@ xfs_qm_init_quotainfo(
 
 	qinf = mp->m_quotainfo = kmem_zalloc(sizeof(xfs_quotainfo_t), KM_SLEEP);
 
+	if ((error = list_lru_init(&qinf->qi_lru))) {
+		kmem_free(qinf);
+		mp->m_quotainfo = NULL;
+		return error;
+	}
+
 	/*
 	 * See if quotainodes are setup, and if not, allocate them,
 	 * and change the superblock accordingly.
 	 */
 	if ((error = xfs_qm_init_quotainos(mp))) {
+		list_lru_destroy(&qinf->qi_lru);
 		kmem_free(qinf);
 		mp->m_quotainfo = NULL;
 		return error;
@@ -846,8 +853,6 @@ xfs_qm_init_quotainfo(
 	INIT_RADIX_TREE(&qinf->qi_pquota_tree, GFP_NOFS);
 	mutex_init(&qinf->qi_tree_lock);
 
-	list_lru_init(&qinf->qi_lru);
-
 	/* mutex used to serialize quotaoffs */
 	mutex_init(&qinf->qi_quotaofflock);
 
@@ -935,6 +940,7 @@ xfs_qm_destroy_quotainfo(
 	qi = mp->m_quotainfo;
 	ASSERT(qi != NULL);
 
+	list_lru_destroy(&qi->qi_lru);
 	unregister_shrinker(&qi->qi_shrinker);
 
 	if (qi->qi_uquotaip) {