ocfs2/dlm: Link all lockres' to a tracking list

This patch links all the lockres' to a tracking list in dlm_ctxt.
We will use this in an upcoming patch that will walk the entire
list and to dump the lockres states to a debugfs file.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

fs/ocfs2/dlm/dlmcommon.h

@@ -101,6 +101,7 @@ struct dlm_ctxt
 	struct list_head purge_list;
 	struct list_head pending_asts;
 	struct list_head pending_basts;
+	struct list_head tracking_list;
 	unsigned int purge_count;
 	spinlock_t spinlock;
 	spinlock_t ast_lock;
@@ -270,6 +271,9 @@ struct dlm_lock_resource
 	struct list_head dirty;
 	struct list_head recovering; // dlm_recovery_ctxt.resources list
 
+	/* Added during init and removed during release */
+	struct list_head tracking;	/* dlm->tracking_list */
+
 	/* unused lock resources have their last_used stamped and are
 	 * put on a list for the dlm thread to run. */
 	unsigned long    last_used;

fs/ocfs2/dlm/dlmdomain.c

@@ -644,6 +644,7 @@ int dlm_shutting_down(struct dlm_ctxt *dlm)
 void dlm_unregister_domain(struct dlm_ctxt *dlm)
 {
 	int leave = 0;
+	struct dlm_lock_resource *res;
 
 	spin_lock(&dlm_domain_lock);
 	BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
@@ -673,6 +674,15 @@ void dlm_unregister_domain(struct dlm_ctxt *dlm)
 			msleep(500);
 			mlog(0, "%s: more migration to do\n", dlm->name);
 		}
+
+		/* This list should be empty. If not, print remaining lockres */
+		if (!list_empty(&dlm->tracking_list)) {
+			mlog(ML_ERROR, "Following lockres' are still on the "
+			     "tracking list:\n");
+			list_for_each_entry(res, &dlm->tracking_list, tracking)
+				dlm_print_one_lock_resource(res);
+		}
+
 		dlm_mark_domain_leaving(dlm);
 		dlm_leave_domain(dlm);
 		dlm_complete_dlm_shutdown(dlm);
@@ -1526,6 +1536,7 @@ static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
 	INIT_LIST_HEAD(&dlm->reco.node_data);
 	INIT_LIST_HEAD(&dlm->purge_list);
 	INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
+	INIT_LIST_HEAD(&dlm->tracking_list);
 	dlm->reco.state = 0;
 
 	INIT_LIST_HEAD(&dlm->pending_asts);

fs/ocfs2/dlm/dlmmaster.c

@@ -639,6 +639,14 @@ static void dlm_lockres_release(struct kref *kref)
 	mlog(0, "destroying lockres %.*s\n", res->lockname.len,
 	     res->lockname.name);
 
+	if (!list_empty(&res->tracking))
+		list_del_init(&res->tracking);
+	else {
+		mlog(ML_ERROR, "Resource %.*s not on the Tracking list\n",
+		     res->lockname.len, res->lockname.name);
+		dlm_print_one_lock_resource(res);
+	}
+
 	if (!hlist_unhashed(&res->hash_node) ||
 	    !list_empty(&res->granted) ||
 	    !list_empty(&res->converting) ||
@@ -706,6 +714,7 @@ static void dlm_init_lockres(struct dlm_ctxt *dlm,
 	INIT_LIST_HEAD(&res->dirty);
 	INIT_LIST_HEAD(&res->recovering);
 	INIT_LIST_HEAD(&res->purge);
+	INIT_LIST_HEAD(&res->tracking);
 	atomic_set(&res->asts_reserved, 0);
 	res->migration_pending = 0;
 	res->inflight_locks = 0;
@@ -721,6 +730,8 @@ static void dlm_init_lockres(struct dlm_ctxt *dlm,
 
 	res->last_used = 0;
 
+	list_add_tail(&res->tracking, &dlm->tracking_list);
+
 	memset(res->lvb, 0, DLM_LVB_LEN);
 	memset(res->refmap, 0, sizeof(res->refmap));
 }