From: Liam R. Howlett <Liam.Howlett@oracle.com>
Date: Thu, 16 Sep 2021 15:04:39 +0000 (-0400)
Subject: maple_tree: Detangle part 1 of many
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=07b38a067e5444c49e0d99ef201c72ca2458a0f4;p=users%2Fjedix%2Flinux-maple.git

maple_tree: Detangle part 1 of many

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 820285e3b432..27d61ce2b4f6 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -3917,16 +3917,6 @@ static inline bool mas_slot_store(struct ma_state *mas, void *entry,
 	unsigned long lmax; /* Logical max. */
 	unsigned char offset = mas->offset;
 
-	if (min == mas->index && max == mas->last) {
-		/* exact fit. */
-		rcu_assign_pointer(slots[offset], entry);
-		goto done;
-	}
-
-	/* out of room. */
-	if (unlikely(offset + 1 >= mt_slots[mt]))
-		return false;
-
 	if (max > mas->last) {
 		if ((min != mas->index) || (offset != end))
 			goto try_node_store;
@@ -3998,13 +3988,16 @@ try_node_store:
  */
 static inline void *_mas_store(struct ma_state *mas, void *entry, bool overwrite)
 {
-	unsigned long r_max, r_min;
+	unsigned long r_max, r_min; /* Ranges */
+	unsigned long end_piv;
 	unsigned char end, zero;
 	void *content = NULL;
 	struct maple_big_node b_node;
 	void __rcu **slots;
 	enum maple_type mt;
 	struct maple_node *node;
+	unsigned long *pivots;
+	unsigned char offset_end;
 
 	int ret = 0;
 
@@ -4039,32 +4032,36 @@ static inline void *_mas_store(struct ma_state *mas, void *entry, bool overwrite
 		mas_set_err(mas, -EEXIST);
 		return content;
 	}
+
+	pivots = ma_pivots(node, mt);
+	offset_end = mas->offset;
+	end_piv = r_max;
+	end = mas_data_end(mas);
+	while ((mas->last > end_piv) && (offset_end < end))
+		end_piv = pivots[++offset_end];
+
+	if (mas->last > end_piv)
+		end_piv = mas->max;
+
+
 	// FIXME: Try finding end offset out here and passing it through.
 	// Maybe a struct for writes?
 	// lmax and offset_end ?
 
 	if (!entry) {
-		unsigned char offset_end = mas->offset;
+		/* Check next slot(s) if we are overwriting the end */
+		if ((mas->last == end_piv) && !slots[offset_end + 1]) {
+			if (offset_end + 1 == end)
+				mas->last = mas->max;
+			else
+				mas->last = pivots[offset_end + 1];
+		} else if ((mas->last > end_piv) && !slots[offset_end])
+			mas->last = end_piv;
 
 		if (!content) {
 			/* If this one is null, the next and prev are not */
 			mas->index = r_min;
-			if (mas->last < r_max)
-				mas->last = r_max;
 		} else {
-			unsigned long *pivots = ma_pivots(node, mt);
-			unsigned long piv = r_max;
-
-			/* Check next slot(s) if we are overwriting the end */
-			if (mas->last >= piv) {
-				while (mas->last >= piv && mas->last != ULONG_MAX)
-					piv = mas_logical_pivot(mas, pivots,
-							      ++offset_end, mt);
-
-				if (!slots[offset_end])
-					mas->last = piv;
-			}
-
 			/* Check prev slot if we are overwriting the start */
 			if (mas->index == r_min && mas->offset &&
 			    !slots[mas->offset - 1]) {
@@ -4076,14 +4073,27 @@ static inline void *_mas_store(struct ma_state *mas, void *entry, bool overwrite
 		}
 	}
 
-	end = mas_data_end(mas);
-	if (mas_slot_store(mas, entry, r_min, r_max, end, content, mt, slots))
+	if (r_min == mas->index && r_max == mas->last) {
+		rcu_assign_pointer(slots[mas->offset], entry);
+		if (!!entry ^ !!content)
+			mas_update_gap(mas);
+		return content;
+	}
+
+	if (unlikely(mas->offset + 1 >= mt_slots[mt]))
+		goto slow_path;
+
+	if ((offset_end - mas->offset <= 1) &&
+	    mas_slot_store(mas, entry, r_min, r_max, end, content, mt, slots))
 		return content;
+	else if ((mas->offset + 1 >= mt_slots[mt]) &&
+		 mas_node_store(mas, entry, r_min, r_max, end, content, mt, slots, pivots))
+		 return content;
 
 	if (mas_is_err(mas))
 		return content;
 
-	/* Slow path. */
+slow_path:
 	b_node.type = mte_node_type(mas->node);
 	b_node.b_end = mas_store_b_node(mas, &b_node, entry, end);
 	b_node.min = mas->min;