diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c
index 8120f136af93..cdf660344c28 100644
--- a/fs/xfs/xfs_discard.c
+++ b/fs/xfs/xfs_discard.c
@@ -200,12 +200,12 @@ xfs_trim_gather_extents(
 		error = xfs_alloc_lookup_le(cur, tcur->start, 0, &i);
 		if (!error && !i)
 			error = xfs_alloc_lookup_ge(cur, tcur->start, 0, &i);
-	} else if (tcur->restart_bno == NULLAGBLOCK) {
-		/* first time through a by-len starts with max length */
-		cur = xfs_cntbt_init_cursor(mp, tp, agbp, pag);
-		error = xfs_alloc_lookup_ge(cur, 0, tcur->count, &i);
 	} else {
-		/* nth time through a by-len starts where we left off */
+		/*
+		 * A by-len walk starts at the last record of the longest
+		 * length (restart_bno is NULLAGBLOCK until the first batch
+		 * ends) and then where the previous batch stopped.
+		 */
 		cur = xfs_cntbt_init_cursor(mp, tp, agbp, pag);
 		error = xfs_alloc_lookup_le(cur, tcur->restart_bno,
 					    tcur->count, &i);