[PATCH v2 5/5] maple_tree: add a test checking storing null

[Liam R. Howlett]

* Wei Yang <richard.weiyang at gmail.com> [241017 09:46]:
> Add a test to assert that, when storing null to am empty tree or a
> single entry tree it will not result into:
> 
>   * a root node with range [0, ULONG_MAX] set to NULL
>   * a root node with consecutive slot set to NULL

Is there any reason this isn't in lib/test_maple_tree.c ?

Does it need internal interfaces at all?

> 
> Signed-off-by: Wei Yang <richard.weiyang at gmail.com>
> CC: Liam R. Howlett <Liam.Howlett at Oracle.com>
> CC: Sidhartha Kumar <sidhartha.kumar at oracle.com>
> CC: Lorenzo Stoakes <lorenzo.stoakes at oracle.com>
> ---
>  tools/testing/radix-tree/maple.c | 73 ++++++++++++++++++++++++++++++++
>  1 file changed, 73 insertions(+)
> 
> diff --git a/tools/testing/radix-tree/maple.c b/tools/testing/radix-tree/maple.c
> index 5fde09999be4..fbb08f151b01 100644
> --- a/tools/testing/radix-tree/maple.c
> +++ b/tools/testing/radix-tree/maple.c
> @@ -35867,6 +35867,75 @@ static noinline void __init check_locky(struct maple_tree *mt)
>  	mt_clear_in_rcu(mt);
>  }
>  
> +static noinline void __init check_store_null(struct maple_tree *mt)
> +{
> +	MA_STATE(ms, mt, 0, ULONG_MAX);
> +
> +	mt_set_non_kernel(10);
> +
> +	/*
> +	 * Store NULL at range [0, ULONG_MAX] to an empty tree should result
> +	 * in an empty tree
> +	 */
> +	mas_store(&ms, NULL);
> +	MT_BUG_ON(mt, !mtree_empty(mt));
> +	mtree_destroy(mt);
> +
> +	/*
> +	 * Store NULL at any range to an empty tree should result in an empty
> +	 * tree
> +	 */
> +	mas_set_range(&ms, 3, 10);
> +	mas_store(&ms, NULL);
> +	MT_BUG_ON(mt, !mtree_empty(mt));
> +	mtree_destroy(mt);
> +
> +	/*
> +	 * Store NULL at range [0, ULONG_MAX] to a single entry tree should
> +	 * result in an empty tree
> +	 */
> +	mas_set(&ms, 0);
> +	mas_store(&ms, &ms);
> +	mas_set_range(&ms, 0, ULONG_MAX);
> +	mas_store(&ms, NULL);
> +	MT_BUG_ON(mt, !mtree_empty(mt));
> +	mtree_destroy(mt);
> +
> +	/*
> +	 * Store NULL at range [0, n] to a single entry tree should
> +	 * result in an empty tree
> +	 */
> +	mas_set(&ms, 0);
> +	mas_store(&ms, &ms);
> +	mas_set_range(&ms, 0, 5);
> +	mas_store(&ms, NULL);
> +	MT_BUG_ON(mt, !mtree_empty(mt));
> +	mtree_destroy(mt);
> +
> +	/*
> +	 * Store NULL at range [m, n] where m > 0 to a single entry tree
> +	 * should still be a single entry tree
> +	 */
> +	mas_set(&ms, 0);
> +	mas_store(&ms, &ms);
> +	mas_set_range(&ms, 2, 5);
> +	mas_store(&ms, NULL);
> +	MT_BUG_ON(mt, mtree_empty(mt));
> +	MT_BUG_ON(mt, xa_is_node(mt->ma_root));
> +	mtree_destroy(mt);
> +
> +	/*
> +	 * Store NULL at range [0, ULONG_MAX] to a tree with node should
> +	 * result in an empty tree
> +	 */
> +	mas_set_range(&ms, 1, 3);
> +	mas_store(&ms, &ms);
> +	mas_set_range(&ms, 0, ULONG_MAX);
> +	mas_store(&ms, NULL);
> +	MT_BUG_ON(mt, !mtree_empty(mt));
> +	mtree_destroy(mt);
> +}
> +
>  /*
>   * Compares two nodes except for the addresses stored in the nodes.
>   * Returns zero if they are the same, otherwise returns non-zero.
> @@ -36344,6 +36413,10 @@ void farmer_tests(void)
>  	node->parent = ma_parent_ptr(node);
>  	ma_free_rcu(node);
>  
> +	mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
> +	check_store_null(&tree);
> +	mtree_destroy(&tree);
> +
>  	/* Check things that will make lockdep angry */
>  	mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
>  	check_locky(&tree);
> -- 
> 2.34.1
>