diff mbox series

[v4,13/17] maple_tree: have mas_store() allocate nodes if needed

Message ID 20240814161944.55347-14-sidhartha.kumar@oracle.com (mailing list archive)
State New
Headers show
Series Introduce a store type enum for the Maple tree | expand

Commit Message

Sidhartha Kumar Aug. 14, 2024, 4:19 p.m. UTC 
Not all users of mas_store() enter with nodes already preallocated.
Check for the MA_STATE_PREALLOC flag to decide whether to preallocate nodes
within mas_store() rather than relying on future write helper functions
to perform the allocations. This allows the write helper functions to be
simplified as they do not have to do checks to make sure there are
enough allocated nodes to perform the write.

Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
---
 lib/maple_tree.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 6640ca775808..d5e020dd93fa 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -5477,13 +5477,12 @@  static inline void mte_destroy_walk(struct maple_enode *enode,
  * @entry: The entry to store.
  *
  * The @mas->index and @mas->last is used to set the range for the @entry.
- * Note: The @mas should have pre-allocated entries to ensure there is memory to
- * store the entry.  Please see mas_expected_entries()/mas_destroy() for more details.
  *
  * Return: the first entry between mas->index and mas->last or %NULL.
  */
 void *mas_store(struct ma_state *mas, void *entry)
 {
+	int request;
 	MA_WR_STATE(wr_mas, mas, entry);
 
 	trace_ma_write(__func__, mas, 0, entry);
@@ -5506,7 +5505,23 @@  void *mas_store(struct ma_state *mas, void *entry)
 	 */
 	mas_wr_prealloc_setup(&wr_mas);
 	mas_wr_store_type(&wr_mas);
+	if (mas->mas_flags & MA_STATE_PREALLOC) {
+		mas_wr_store_entry(&wr_mas);
+		MAS_WR_BUG_ON(&wr_mas, mas_is_err(mas));
+		return wr_mas.content;
+	}
+
+	request = mas_prealloc_calc(mas, entry);
+	if (!request)
+		goto store;
+
+	mas_node_count(mas, request);
+	if (mas_is_err(mas))
+		return NULL;
+
+store:
 	mas_wr_store_entry(&wr_mas);
+	mas_destroy(mas);
 	return wr_mas.content;
 }
 EXPORT_SYMBOL_GPL(mas_store);