From 431e10601913f8f2006f3ed607e73eedf264b426 Mon Sep 17 00:00:00 2001 From: Wei Yang Date: Thu, 31 Oct 2024 23:16:27 +0000 Subject: [PATCH] maple_tree: add a test checking storing null 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 [akpm@linux-foundation.org: work around build error (mas_root)] Link: https://lkml.kernel.org/r/20241031231627.14316-6-richard.weiyang@gmail.com Signed-off-by: Wei Yang Reviewed-by: Liam R. Howlett Cc: Liam R. Howlett Cc: Sidhartha Kumar Cc: Lorenzo Stoakes Signed-off-by: Andrew Morton --- lib/test_maple_tree.c | 90 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c index 31561e0e1a0d..704cb1093ae8 100644 --- a/lib/test_maple_tree.c +++ b/lib/test_maple_tree.c @@ -1387,6 +1387,92 @@ static noinline void __init check_prev_entry(struct maple_tree *mt) mas_unlock(&mas); } +static noinline void __init check_store_null(struct maple_tree *mt) +{ + MA_STATE(mas, mt, 0, ULONG_MAX); + + /* + * Store NULL at range [0, ULONG_MAX] to an empty tree should result + * in an empty tree + */ + mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE); + mas_lock(&mas); + mas_store_gfp(&mas, NULL, GFP_KERNEL); + MT_BUG_ON(mt, !mtree_empty(mt)); + mas_unlock(&mas); + mtree_destroy(mt); + + /* + * Store NULL at any range to an empty tree should result in an empty + * tree + */ + mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE); + mas_lock(&mas); + mas_set_range(&mas, 3, 10); + mas_store_gfp(&mas, NULL, GFP_KERNEL); + MT_BUG_ON(mt, !mtree_empty(mt)); + mas_unlock(&mas); + mtree_destroy(mt); + + /* + * Store NULL at range [0, ULONG_MAX] to a single entry tree should + * result in an empty tree + */ + mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE); + mas_lock(&mas); + mas_set(&mas, 0); + mas_store_gfp(&mas, &mas, GFP_KERNEL); + mas_set_range(&mas, 0, ULONG_MAX); + mas_store_gfp(&mas, NULL, GFP_KERNEL); + MT_BUG_ON(mt, !mtree_empty(mt)); + mas_unlock(&mas); + mtree_destroy(mt); + + /* + * Store NULL at range [0, n] to a single entry tree should + * result in an empty tree + */ + mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE); + mas_lock(&mas); + mas_set(&mas, 0); + mas_store_gfp(&mas, &mas, GFP_KERNEL); + mas_set_range(&mas, 0, 5); + mas_store_gfp(&mas, NULL, GFP_KERNEL); + MT_BUG_ON(mt, !mtree_empty(mt)); + mas_unlock(&mas); + mtree_destroy(mt); + + /* + * Store NULL at range [m, n] where m > 0 to a single entry tree + * should still be a single entry tree + */ + mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE); + mas_lock(&mas); + mas_set(&mas, 0); + mas_store_gfp(&mas, &mas, GFP_KERNEL); + mas_set_range(&mas, 2, 5); + mas_store_gfp(&mas, NULL, GFP_KERNEL); + MT_BUG_ON(mt, mtree_empty(mt)); +// MT_BUG_ON(mt, xa_is_node(mas_root(&mas))); + mas_unlock(&mas); + mtree_destroy(mt); + + /* + * Store NULL at range [0, ULONG_MAX] to a tree with node should + * result in an empty tree + */ + mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE); + mas_lock(&mas); + mas_set_range(&mas, 1, 3); + mas_store_gfp(&mas, &mas, GFP_KERNEL); +// MT_BUG_ON(mt, !xa_is_node(mas_root(&mas))); + mas_set_range(&mas, 0, ULONG_MAX); + mas_store_gfp(&mas, NULL, GFP_KERNEL); + MT_BUG_ON(mt, !mtree_empty(mt)); + mas_unlock(&mas); + mtree_destroy(mt); +} + static noinline void __init check_root_expand(struct maple_tree *mt) { MA_STATE(mas, mt, 0, 0); @@ -3710,6 +3796,10 @@ static int __init maple_tree_seed(void) goto skip; #endif + mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE); + check_store_null(&tree); + mtree_destroy(&tree); + mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE); check_root_expand(&tree); mtree_destroy(&tree);