[PATCH 02/14] maple_tree: Add benchmarking for mas_prev()

From: Liam R. Howlett
Date: Wed May 31 2023 - 22:16:53 EST


Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
---
lib/test_maple_tree.c | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)

diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c
index 3dbf99c3f2b1..15d7b7bce7d6 100644
--- a/lib/test_maple_tree.c
+++ b/lib/test_maple_tree.c
@@ -45,6 +45,7 @@ atomic_t maple_tree_tests_passed;
/* #define BENCH_MT_FOR_EACH */
/* #define BENCH_FORK */
/* #define BENCH_MAS_FOR_EACH */
+/* #define BENCH_MAS_PREV */

#ifdef __KERNEL__
#define mt_set_non_kernel(x) do {} while (0)
@@ -1735,7 +1736,35 @@ static noinline void __init bench_mas_for_each(struct maple_tree *mt)

}
#endif
+#if defined(BENCH_MAS_PREV)
+static noinline void __init bench_mas_prev(struct maple_tree *mt)
+{
+ int i, count = 1000000;
+ unsigned long max = 2500;
+ void *entry;
+ MA_STATE(mas, mt, 0, 0);
+
+ for (i = 0; i < max; i += 5) {
+ int gap = 4;
+ if (i % 30 == 0)
+ gap = 3;
+ mtree_store_range(mt, i, i + gap, xa_mk_value(i), GFP_KERNEL);
+ }

+ rcu_read_lock();
+ for (i = 0; i < count; i++) {
+ unsigned long j = 2495;
+
+ mas_set(&mas, ULONG_MAX);
+ while ((entry = mas_prev(&mas, 0)) != NULL) {
+ MT_BUG_ON(mt, entry != xa_mk_value(j));
+ j -= 5;
+ }
+ }
+ rcu_read_unlock();
+
+}
+#endif
/* check_forking - simulate the kernel forking sequence with the tree. */
static noinline void __init check_forking(struct maple_tree *mt)
{
@@ -3468,6 +3497,13 @@ static int __init maple_tree_seed(void)
mtree_destroy(&tree);
goto skip;
#endif
+#if defined(BENCH_MAS_PREV)
+#define BENCH
+ mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
+ bench_mas_prev(&tree);
+ mtree_destroy(&tree);
+ goto skip;
+#endif

mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
check_iteration(&tree);
--
2.39.2