maple_tree: move mas_wr_end_piv() below mas_wr_extend_null()

Relocate it and call mas_wr_extend_null() from within mas_wr_end_piv().
Extending the NULL may affect the end pivot value so call
mas_wr_endtend_null() from within mas_wr_end_piv() to keep it all
together.

Link: https://lkml.kernel.org/r/20230724183157.3939892-12-Liam.Howlett@oracle.comSigned-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

lib/maple_tree.c

@@ -4180,18 +4180,6 @@ static inline bool mas_wr_slot_store(struct ma_wr_state *wr_mas)
 	return true;
 }
 
-static inline void mas_wr_end_piv(struct ma_wr_state *wr_mas)
-{
-	while ((wr_mas->offset_end < wr_mas->node_end) &&
-	       (wr_mas->mas->last > wr_mas->pivots[wr_mas->offset_end]))
-		wr_mas->offset_end++;
-
-	if (wr_mas->offset_end < wr_mas->node_end)
-		wr_mas->end_piv = wr_mas->pivots[wr_mas->offset_end];
-	else
-		wr_mas->end_piv = wr_mas->mas->max;
-}
-
 static inline void mas_wr_extend_null(struct ma_wr_state *wr_mas)
 {
 	struct ma_state *mas = wr_mas->mas;
@@ -4228,6 +4216,21 @@ static inline void mas_wr_extend_null(struct ma_wr_state *wr_mas)
 	}
 }
 
+static inline void mas_wr_end_piv(struct ma_wr_state *wr_mas)
+{
+	while ((wr_mas->offset_end < wr_mas->node_end) &&
+	       (wr_mas->mas->last > wr_mas->pivots[wr_mas->offset_end]))
+		wr_mas->offset_end++;
+
+	if (wr_mas->offset_end < wr_mas->node_end)
+		wr_mas->end_piv = wr_mas->pivots[wr_mas->offset_end];
+	else
+		wr_mas->end_piv = wr_mas->mas->max;
+
+	if (!wr_mas->entry)
+		mas_wr_extend_null(wr_mas);
+}
+
 static inline unsigned char mas_wr_new_end(struct ma_wr_state *wr_mas)
 {
 	struct ma_state *mas = wr_mas->mas;
@@ -4371,10 +4374,6 @@ static inline void *mas_wr_store_entry(struct ma_wr_state *wr_mas)
 
 	/* At this point, we are at the leaf node that needs to be altered. */
 	mas_wr_end_piv(wr_mas);
-
-	if (!wr_mas->entry)
-		mas_wr_extend_null(wr_mas);
-
 	/* New root for a single pointer */
 	if (unlikely(!mas->index && mas->last == ULONG_MAX)) {
 		mas_new_root(mas, wr_mas->entry);