maple_tree: simplify mas_commit_b_node()

The only callers of mas_commit_b_node() are those with store type of
wr_rebalance and wr_split_store. Use mas->store_type to dispatch to the
correct helper function. This allows the removal of mas_reuse_node() as
it is no longer used.

Link: https://lkml.kernel.org/r/20240814161944.55347-12-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index bb940f61d71390fb8848b14ecb933d94265dce63..0314e9b526218f0cdf8c520533e3a42e26b0ab78 100644 (file)
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -3395,72 +3395,22 @@ static int mas_split(struct ma_state *mas, struct maple_big_node *b_node)
        return 1;
 }
 
-/*
- * mas_reuse_node() - Reuse the node to store the data.
- * @wr_mas: The maple write state
- * @bn: The maple big node
- * @end: The end of the data.
- *
- * Will always return false in RCU mode.
- *
- * Return: True if node was reused, false otherwise.
- */
-static inline bool mas_reuse_node(struct ma_wr_state *wr_mas,
-                         struct maple_big_node *bn, unsigned char end)
-{
-       /* Need to be rcu safe. */
-       if (mt_in_rcu(wr_mas->mas->tree))
-               return false;
-
-       if (end > bn->b_end) {
-               int clear = mt_slots[wr_mas->type] - bn->b_end;
-
-               memset(wr_mas->slots + bn->b_end, 0, sizeof(void *) * clear--);
-               memset(wr_mas->pivots + bn->b_end, 0, sizeof(void *) * clear);
-       }
-       mab_mas_cp(bn, 0, bn->b_end, wr_mas->mas, false);
-       return true;
-}
-
 /*
  * mas_commit_b_node() - Commit the big node into the tree.
  * @wr_mas: The maple write state
  * @b_node: The maple big node
- * @end: The end of the data.
  */
 static noinline_for_kasan int mas_commit_b_node(struct ma_wr_state *wr_mas,
-                           struct maple_big_node *b_node, unsigned char end)
+                           struct maple_big_node *b_node)
 {
-       struct maple_node *node;
-       struct maple_enode *old_enode;
-       unsigned char b_end = b_node->b_end;
-       enum maple_type b_type = b_node->type;
-
-       old_enode = wr_mas->mas->node;
-       if ((b_end < mt_min_slots[b_type]) &&
-           (!mte_is_root(old_enode)) &&
-           (mas_mt_height(wr_mas->mas) > 1))
-               return mas_rebalance(wr_mas->mas, b_node);
-
-       if (b_end >= mt_slots[b_type])
-               return mas_split(wr_mas->mas, b_node);
+       enum store_type type = wr_mas->mas->store_type;
 
-       if (mas_reuse_node(wr_mas, b_node, end))
-               goto reuse_node;
+       WARN_ON_ONCE(type != wr_rebalance && type != wr_split_store);
 
-       mas_node_count(wr_mas->mas, 1);
-       if (mas_is_err(wr_mas->mas))
-               return 0;
+       if (type == wr_rebalance)
+               return mas_rebalance(wr_mas->mas, b_node);
 
-       node = mas_pop_node(wr_mas->mas);
-       node->parent = mas_mn(wr_mas->mas)->parent;
-       wr_mas->mas->node = mt_mk_node(node, b_type);
-       mab_mas_cp(b_node, 0, b_end, wr_mas->mas, false);
-       mas_replace_node(wr_mas->mas, old_enode);
-reuse_node:
-       mas_update_gap(wr_mas->mas);
-       wr_mas->mas->end = b_end;
-       return 1;
+       return mas_split(wr_mas->mas, b_node);
 }
 
 /*
@@ -4155,7 +4105,7 @@ static void mas_wr_bnode(struct ma_wr_state *wr_mas)
        trace_ma_write(__func__, wr_mas->mas, 0, wr_mas->entry);
        memset(&b_node, 0, sizeof(struct maple_big_node));
        mas_store_b_node(wr_mas, &b_node, wr_mas->offset_end);
-       mas_commit_b_node(wr_mas, &b_node, wr_mas->mas->end);
+       mas_commit_b_node(wr_mas, &b_node);
 }
 
 static inline void mas_wr_modify(struct ma_wr_state *wr_mas)