dlm: drop own rsb pre allocation mechanism

This patch drops the own written rsb pre allocation mechanism as this is
already done by using kmem caches, we don't need another layer on top of
that to running some pre allocation scheme.

Signed-off-by: Alexander Aring <[e-mail]>
Signed-off-by: David Teigland <[e-mail]>

fs/dlm/dlm_internal.h

···
 	unsigned long		res_toss_time;
 	uint32_t		res_first_lkid;
 	struct list_head	res_lookup;	/* lkbs waiting on first */
-	union {
-		struct list_head	res_hashchain;
-		struct rhash_head	res_node; /* rsbtbl */
-	};
+	struct rhash_head	res_node;	/* rsbtbl */
 	struct list_head	res_grantqueue;
 	struct list_head	res_convertqueue;
 	struct list_head	res_waitqueue;
···
 
 	spinlock_t		ls_orphans_lock;
 	struct list_head	ls_orphans;
-
-	spinlock_t		ls_new_rsb_spin;
-	int			ls_new_rsb_count;
-	struct list_head	ls_new_rsb;	/* new rsb structs */
 
 	struct list_head	ls_nodes;	/* current nodes in ls */
 	struct list_head	ls_nodes_gone;	/* dead node list, recovery */

fs/dlm/lock.c

···
 	put_rsb(r);
 }
 
-static int pre_rsb_struct(struct dlm_ls *ls)
-{
-	struct dlm_rsb *r1, *r2;
-	int count = 0;
-
-	spin_lock_bh(&ls->ls_new_rsb_spin);
-	if (ls->ls_new_rsb_count > dlm_config.ci_new_rsb_count / 2) {
-		spin_unlock_bh(&ls->ls_new_rsb_spin);
-		return 0;
-	}
-	spin_unlock_bh(&ls->ls_new_rsb_spin);
-
-	r1 = dlm_allocate_rsb(ls);
-	r2 = dlm_allocate_rsb(ls);
-
-	spin_lock_bh(&ls->ls_new_rsb_spin);
-	if (r1) {
-		list_add(&r1->res_hashchain, &ls->ls_new_rsb);
-		ls->ls_new_rsb_count++;
-	}
-	if (r2) {
-		list_add(&r2->res_hashchain, &ls->ls_new_rsb);
-		ls->ls_new_rsb_count++;
-	}
-	count = ls->ls_new_rsb_count;
-	spin_unlock_bh(&ls->ls_new_rsb_spin);
-
-	if (!count)
-		return -ENOMEM;
-	return 0;
-}
-
 /* connected with timer_delete_sync() in dlm_ls_stop() to stop
  * new timers when recovery is triggered and don't run them
  * again until a dlm_timer_resume() tries it again.
···
 			  struct dlm_rsb **r_ret)
 {
 	struct dlm_rsb *r;
-	int count;
 
-	spin_lock_bh(&ls->ls_new_rsb_spin);
-	if (list_empty(&ls->ls_new_rsb)) {
-		count = ls->ls_new_rsb_count;
-		spin_unlock_bh(&ls->ls_new_rsb_spin);
-		log_debug(ls, "find_rsb retry %d %d %s",
-			  count, dlm_config.ci_new_rsb_count,
-			  (const char *)name);
-		return -EAGAIN;
-	}
-
-	r = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb, res_hashchain);
-	list_del(&r->res_hashchain);
-	ls->ls_new_rsb_count--;
-	spin_unlock_bh(&ls->ls_new_rsb_spin);
+	r = dlm_allocate_rsb(ls);
+	if (!r)
+		return -ENOMEM;
 
 	r->res_ls = ls;
 	r->res_length = len;
···
 	}
 
  retry:
-	if (create) {
-		error = pre_rsb_struct(ls);
-		if (error < 0)
-			goto out;
-	}
-
- retry_lookup:
 
 	/* check if the rsb is in keep state under read lock - likely path */
 	read_lock_bh(&ls->ls_rsbtbl_lock);
···
 	if (!error) {
 		if (!rsb_flag(r, RSB_TOSS)) {
 			write_unlock_bh(&ls->ls_rsbtbl_lock);
-			goto retry_lookup;
+			goto retry;
 		}
 	} else {
 		write_unlock_bh(&ls->ls_rsbtbl_lock);
···
 		goto out;
 
 	error = get_rsb_struct(ls, name, len, &r);
-	if (error == -EAGAIN)
-		goto retry;
-	if (error)
+	if (WARN_ON_ONCE(error))
 		goto out;
 
 	r->res_hash = hash;
···
 		 */
 		write_unlock_bh(&ls->ls_rsbtbl_lock);
 		dlm_free_rsb(r);
-		goto retry_lookup;
+		goto retry;
 	} else if (!error) {
 		list_add(&r->res_rsbs_list, &ls->ls_keep);
 	}
···
 	int error;
 
  retry:
-	error = pre_rsb_struct(ls);
-	if (error < 0)
-		goto out;
-
- retry_lookup:
 
 	/* check if the rsb is in keep state under read lock - likely path */
 	read_lock_bh(&ls->ls_rsbtbl_lock);
···
 	if (!error) {
 		if (!rsb_flag(r, RSB_TOSS)) {
 			write_unlock_bh(&ls->ls_rsbtbl_lock);
-			goto retry_lookup;
+			goto retry;
 		}
 	} else {
 		write_unlock_bh(&ls->ls_rsbtbl_lock);
···
 	 */
 
 	error = get_rsb_struct(ls, name, len, &r);
-	if (error == -EAGAIN) {
-		goto retry;
-	}
-	if (error)
+	if (WARN_ON_ONCE(error))
 		goto out;
 
 	r->res_hash = hash;
···
 		 */
 		write_unlock_bh(&ls->ls_rsbtbl_lock);
 		dlm_free_rsb(r);
-		goto retry_lookup;
+		goto retry;
 	} else if (!error) {
 		list_add(&r->res_rsbs_list, &ls->ls_keep);
 	}
···
 	}
 
  retry:
-	error = pre_rsb_struct(ls);
-	if (error < 0)
-		return error;
-
- retry_lookup:
 
 	/* check if the rsb is in keep state under read lock - likely path */
 	read_lock_bh(&ls->ls_rsbtbl_lock);
···
 			/* something as changed, very unlikely but
 			 * try again
 			 */
-			goto retry_lookup;
+			goto retry;
 		}
 	} else {
 		write_unlock_bh(&ls->ls_rsbtbl_lock);
···
 
  not_found:
 	error = get_rsb_struct(ls, name, len, &r);
-	if (error == -EAGAIN)
-		goto retry;
-	if (error)
+	if (WARN_ON_ONCE(error))
 		goto out;
 
 	r->res_hash = hash;
···
 		 */
 		write_unlock_bh(&ls->ls_rsbtbl_lock);
 		dlm_free_rsb(r);
-		goto retry_lookup;
+		goto retry;
 	} else if (error) {
 		write_unlock_bh(&ls->ls_rsbtbl_lock);
 		/* should never happen */

fs/dlm/lockspace.c

···
 	INIT_LIST_HEAD(&ls->ls_orphans);
 	spin_lock_init(&ls->ls_orphans_lock);
 
-	INIT_LIST_HEAD(&ls->ls_new_rsb);
-	spin_lock_init(&ls->ls_new_rsb_spin);
-
 	INIT_LIST_HEAD(&ls->ls_nodes);
 	INIT_LIST_HEAD(&ls->ls_nodes_gone);
 	ls->ls_num_nodes = 0;
···
 
 static int release_lockspace(struct dlm_ls *ls, int force)
 {
-	struct dlm_rsb *rsb;
 	int busy, rv;
 
 	busy = lockspace_busy(ls, force);
···
 	 * Free all rsb's on rsbtbl
 	 */
 	rhashtable_free_and_destroy(&ls->ls_rsbtbl, rhash_free_rsb, NULL);
-
-	while (!list_empty(&ls->ls_new_rsb)) {
-		rsb = list_first_entry(&ls->ls_new_rsb, struct dlm_rsb,
-				       res_hashchain);
-		list_del(&rsb->res_hashchain);
-		dlm_free_rsb(rsb);
-	}
 
 	/*
 	 * Free structures on any other lists