From: Liam R. Howlett <Liam.Howlett@oracle.com>
Date: Thu, 23 Sep 2021 19:40:50 +0000 (-0400)
Subject: maple_tree: Continue mas_store optimization
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=55c97526a9cd97552d78f372c06b73566e44007c;p=users%2Fjedix%2Flinux-maple.git

maple_tree: Continue mas_store optimization

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

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 2b7937c5c7ef..b3cb945d74ca 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -3942,7 +3942,7 @@ static inline bool mas_slot_store(struct ma_state *mas, void *entry,
 	unsigned char offset = mas->offset;
 
 	if ((max > mas->last) && ((min != mas->index) || (offset != end)))
-		goto try_node_store;
+		return false;
 
 	if (offset == end - 1)
 		lmax = mas->max;
@@ -3951,43 +3951,35 @@ static inline bool mas_slot_store(struct ma_state *mas, void *entry,
 
 	/* going to overwrite too many slots. */
 	if (lmax < mas->last)
-		goto try_node_store;
+		return false;
 
 	if (min == mas->index) {
 		/* overwriting two or more ranges with one. */
 		if (lmax == mas->last)
-			goto try_node_store;
+			return false;
 
 		/* Overwriting all of offset and a portion of offset + 1. */
 		rcu_assign_pointer(slots[offset], entry);
 		pivots[offset] = mas->last;
 		goto done;
-	} else {
-		/* Doesn't end on the next range end. */
-		if (lmax != mas->last)
-			goto try_node_store;
-
-		/* Overwriting a portion of offset and all of offset + 1 */
-		if (offset + 1 < mt_pivots[mt]) {
-			if (entry || pivots[offset + 1])
-				pivots[offset + 1] = mas->last;
-		}
-		rcu_assign_pointer(slots[offset + 1], entry);
-		pivots[offset] = mas->index - 1;
-		mas->offset++; /* Keep mas accurate. */
-		goto done;
 	}
 
-	return false;
+	/* Doesn't end on the next range end. */
+	if (lmax != mas->last)
+		return false;
+
+	/* Overwriting a portion of offset and all of offset + 1 */
+	if ((offset + 1 < mt_pivots[mt]) && (entry || pivots[offset + 1]))
+			pivots[offset + 1] = mas->last;
 
+	rcu_assign_pointer(slots[offset + 1], entry);
+	pivots[offset] = mas->index - 1;
+	mas->offset++; /* Keep mas accurate. */
 
 done:
 	trace_ma_write(__func__, mas, 0, entry);
 	mas_update_gap(mas);
 	return true;
-
-try_node_store:
-	return mas_node_store(mas, entry, min, max, end, content, mt, slots, pivots);
 }
 
 /*
@@ -4049,14 +4041,12 @@ static inline void *_mas_store(struct ma_state *mas, void *entry, bool overwrite
 	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 ?
@@ -4086,10 +4076,12 @@ static inline void *_mas_store(struct ma_state *mas, void *entry, bool overwrite
 		}
 	}
 
+	/* New root for a single pointer */
 	if (!mas->index && mas->last == ULONG_MAX) {
 		mas_new_root(mas, entry);
 		return content;
 	}
+	/* Direct replacement */
 	if (r_min == mas->index && r_max == mas->last) {
 		rcu_assign_pointer(slots[mas->offset], entry);
 		if (!!entry ^ !!content)
@@ -4097,7 +4089,7 @@ static inline void *_mas_store(struct ma_state *mas, void *entry, bool overwrite
 		return content;
 	}
 
-	/* Appending can skip a lot. */
+	/* Attempt to append */
 	if (entry && (end < mt_slots[mt] - 1) && (mas->offset == end)) {
 		if ((mas->index != r_min) && (mas->last == r_max)) {
 			if (end + 1 < mt_pivots[mt])
@@ -4129,14 +4121,14 @@ static inline void *_mas_store(struct ma_state *mas, void *entry, bool overwrite
 		}
 	}
 
+	/* slot and node store will not fit, go to the slow path */
 	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_piv, 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))
+	else if (mas_node_store(mas, entry, r_min, r_max, end, content, mt, slots, pivots))
 		return content;
 
 	if (mas_is_err(mas))