From: Liam R. Howlett <Liam.Howlett@oracle.com>
Date: Tue, 23 Nov 2021 15:47:43 +0000 (-0500)
Subject: maple_tree: Start using ma_wr_state for spanning_store
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=512279e0819b0edf12e77d935f54e612e8fe2412;p=users%2Fjedix%2Flinux-maple.git

maple_tree: Start using ma_wr_state for spanning_store

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

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index a77208d3c6f53..e5814f6ad967d 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -3522,8 +3522,13 @@ static bool mas_is_span_wr(struct ma_wr_state *wr_mas)
 		 */
 		if ((last == ULONG_MAX) && (last == max))
 			return false;
-	} else if ((piv == last) && entry) {
-		return false;
+	} else if (piv == last) {
+		if (entry)
+			return false;
+
+		/* Detect spanning store wr walk */
+		if ((last == ULONG_MAX) && (wr_mas->mas->index == ULONG_MAX))
+			return false;
 	}
 
 	trace_ma_write(__func__, wr_mas->mas, piv, entry);
@@ -3572,14 +3577,14 @@ static bool mas_wr_walk(struct ma_wr_state *wr_mas)
  */
 static inline void mas_extend_spanning_null(
 		struct ma_state *l_mas, unsigned long r_min, void *content,
-		struct ma_state *r_mas, unsigned long r_max, void *r_content)
+		struct ma_wr_state *r_wr_mas)
 {
 	unsigned char l_slot = l_mas->offset;
-	unsigned char r_slot = r_mas->offset;
-	unsigned char cp_r_slot = r_slot;
 	struct maple_node *l_node = mas_mn(l_mas);
 	enum maple_type l_type = mte_node_type(l_mas->node);
 	void __rcu **slots = ma_slots(l_node, l_type);
+	struct ma_state *r_mas = r_wr_mas->mas;
+
 
 	/* Expand NULL to start of the range. */
 	if (!content)
@@ -3596,26 +3601,16 @@ static inline void mas_extend_spanning_null(
 		l_mas->offset = l_slot - 1;
 	}
 
-	if (!r_content) {
-		if (r_mas->last < r_max)
-			r_mas->last = r_max;
-		cp_r_slot++;
-	}
-
-	slots = ma_slots(mte_to_node(r_mas->node),
-			     mte_node_type(r_mas->node));
-	if ((r_mas->last == r_max) &&
+	if (!r_wr_mas->content) {
+		if (r_mas->last < r_wr_mas->r_max)
+			r_mas->last = r_wr_mas->r_max;
+		r_mas->offset++;
+	} else if ((r_mas->last == r_wr_mas->r_max) &&
 	    (r_mas->last < r_mas->max) &&
-	    !mas_slot_locked(r_mas, slots, r_slot + 1)) {
-		r_mas->last = mas_safe_pivot(r_mas, r_slot + 1);
-		cp_r_slot++;
+	    !mas_slot_locked(r_mas, r_wr_mas->slots, r_mas->offset + 1)) {
+		r_mas->last = mas_safe_pivot(r_mas, r_mas->offset + 1);
+		r_mas->offset++;
 	}
-
-	if (r_slot && !r_mas->last)
-		r_mas->last = r_mas->max;
-
-	if (l_mas != r_mas)
-		r_mas->offset = cp_r_slot;
 }
 
 static inline void *mtree_range_walk(struct ma_state *mas)
@@ -3820,15 +3815,17 @@ done:
  *
  * Return: 0 on error, positive on success.
  */
-static inline int mas_spanning_store(struct ma_state *mas, void *entry)
+static inline int mas_spanning_store(struct ma_wr_state *wr_mas, void *entry)
 {
 	struct maple_big_node b_node;
 	struct maple_subtree_state mast;
-	unsigned char height = mas_mt_height(mas);
-	int node_count = 1 + height * 3;
-	void *content, *r_content;
-	unsigned long r_min, r_max;
+	unsigned char height;
+	int node_count;
+	void *l_content;
+	unsigned long r_min;
 	unsigned char l_end;
+	struct ma_state *mas = wr_mas->mas;
+	struct ma_wr_state r_wr_mas;
 
 	/* Holds new left and right sub-tree */
 	MA_STATE(l_mas, mas->tree, mas->index, mas->index);
@@ -3842,6 +3839,8 @@ static inline int mas_spanning_store(struct ma_state *mas, void *entry)
 	 * Node rebalancing may occur due to this store, so there may be two new
 	 * entries per level plus a new root.
 	 */
+	height = mas_mt_height(mas);
+	node_count = 1 + height * 3;
 	mas_node_count(mas, node_count);
 	if (mas_is_err(mas))
 		return 0;
@@ -3858,20 +3857,19 @@ static inline int mas_spanning_store(struct ma_state *mas, void *entry)
 		r_mas.last++;
 
 	r_mas.index = r_mas.last;
-	r_content = mtree_range_walk(&r_mas);
-	r_max = r_mas.last;
+	r_wr_mas.mas = &r_mas;
+	mas_wr_walk(&r_wr_mas);
 	r_mas.last = r_mas.index = mas->last;
 
 	/* Set up left side. */
 	l_mas = *mas;
-	content = mtree_range_walk(&l_mas);
+	l_content = mtree_range_walk(&l_mas);
 	r_min = l_mas.index;
 	l_mas.index = mas->index;
 	l_mas.last = mas->last;
 
 	if (!entry) {
-		mas_extend_spanning_null(&l_mas, r_min, content,
-					 &r_mas, r_max, r_content);
+		mas_extend_spanning_null(&l_mas, r_min, l_content, &r_wr_mas);
 		mas->index = l_mas.index;
 		mas->last = l_mas.last = r_mas.index = r_mas.last;
 		mas->offset = l_mas.offset;
@@ -3880,9 +3878,9 @@ static inline int mas_spanning_store(struct ma_state *mas, void *entry)
 	/* Copy l_mas and store the value in b_node. */
 	l_end = mas_data_end(&l_mas);
 	b_node.b_end = mas_store_b_node(&l_mas, &b_node, entry, l_end, l_end,
-					content);
+					l_content);
 	/* Copy r_mas into b_node. */
-	mas_mab_cp(&r_mas, r_mas.offset, mt_slot_count(r_mas.node),
+	mas_mab_cp(&r_mas, r_mas.offset, r_wr_mas.node_end,
 		   &b_node, b_node.b_end + 1);
 	/* Stop spanning searches by searching for just index. */
 	l_mas.index = l_mas.last = mas->index;
@@ -4399,7 +4397,7 @@ static inline void *mas_store_entry(struct ma_state *mas, void *entry)
 	wr_mas.mas = mas;
 	wr_mas.entry = entry;
 	if (!mas_wr_walk(&wr_mas)) {
-		mas_spanning_store(mas, entry);
+		mas_spanning_store(&wr_mas, entry);
 		return wr_mas.content;
 	}