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Sun, 15 Oct 2023 20:23:15 -0700 (PDT) Received: from GL4FX4PXWL.bytedance.net ([139.177.225.232]) by smtp.gmail.com with ESMTPSA id d8-20020a17090ae28800b0027758c7f585sm3452770pjz.52.2023.10.15.20.23.08 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Sun, 15 Oct 2023 20:23:15 -0700 (PDT) From: Peng Zhang To: Liam.Howlett@oracle.com, corbet@lwn.net, akpm@linux-foundation.org, willy@infradead.org, brauner@kernel.org, surenb@google.com, michael.christie@oracle.com, mjguzik@gmail.com, mathieu.desnoyers@efficios.com, npiggin@gmail.com, peterz@infradead.org, oliver.sang@intel.com, mst@redhat.com Cc: zhangpeng.00@bytedance.com, maple-tree@lists.infradead.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v5 05/10] maple_tree: Add test for mtree_dup() Date: Mon, 16 Oct 2023 11:22:21 +0800 Message-Id: <20231016032226.59199-6-zhangpeng.00@bytedance.com> X-Mailer: git-send-email 2.39.3 (Apple Git-145) In-Reply-To: <20231016032226.59199-1-zhangpeng.00@bytedance.com> References: <20231016032226.59199-1-zhangpeng.00@bytedance.com> MIME-Version: 1.0 X-Rspam-User: X-Stat-Signature: uwbuj1ncpmfiencf18ftfy7rxy38sf5t X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: D73FAC0012 X-HE-Tag: 1697426596-580937 X-HE-Meta: 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 J6ZnVAQz uvKIhXZRSFHyFfy/BjwsIJ1vJRiGV3tT6pnhcRGkKVEEnL5n+LDJ5O3tp814h4OwDEIWuXLB0RYjjuaOe1wVMvzTDh2bkDs8J8ScmpTlR9pDNXTGlsTuIVdRztvEDuKgji1gcKYb78Y9g78DlDh4xLc0NQesGAsC3UwGgY1U0XJpqlbGRFj6PO2n84vOHlD6b1qxiia9ppkuVxMcOh4jXzhDK24Na+sXpOCAFe6oAKASQwHcWkQeYHM+jgnV+ijWSehFqRcE2GkRNpq7ctsaRWfwWZdXTJDjUG0AJLGEhTF2Ax4R89SLnztNNKoJVioZLz0RLHVXF5AQ7sKutyOu9wb2JKxYdJqKBN5kZ+iaLljvhKkP6bkgMyf2T/Q== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Add test for mtree_dup(). Test by duplicating different maple trees and then comparing the two trees. Includes tests for duplicating full trees and memory allocation failures on different nodes. Signed-off-by: Peng Zhang --- tools/testing/radix-tree/maple.c | 361 +++++++++++++++++++++++++++++++ 1 file changed, 361 insertions(+) diff --git a/tools/testing/radix-tree/maple.c b/tools/testing/radix-tree/maple.c index e5da1cad70ba..12b3390e9591 100644 --- a/tools/testing/radix-tree/maple.c +++ b/tools/testing/radix-tree/maple.c @@ -35857,6 +35857,363 @@ static noinline void __init check_locky(struct maple_tree *mt) mt_clear_in_rcu(mt); } +/* + * Compares two nodes except for the addresses stored in the nodes. + * Returns zero if they are the same, otherwise returns non-zero. + */ +static int __init compare_node(struct maple_enode *enode_a, + struct maple_enode *enode_b) +{ + struct maple_node *node_a, *node_b; + struct maple_node a, b; + void **slots_a, **slots_b; /* Do not use the rcu tag. */ + enum maple_type type; + int i; + + if (((unsigned long)enode_a & MAPLE_NODE_MASK) != + ((unsigned long)enode_b & MAPLE_NODE_MASK)) { + pr_err("The lower 8 bits of enode are different.\n"); + return -1; + } + + type = mte_node_type(enode_a); + node_a = mte_to_node(enode_a); + node_b = mte_to_node(enode_b); + a = *node_a; + b = *node_b; + + /* Do not compare addresses. */ + if (ma_is_root(node_a) || ma_is_root(node_b)) { + a.parent = (struct maple_pnode *)((unsigned long)a.parent & + MA_ROOT_PARENT); + b.parent = (struct maple_pnode *)((unsigned long)b.parent & + MA_ROOT_PARENT); + } else { + a.parent = (struct maple_pnode *)((unsigned long)a.parent & + MAPLE_NODE_MASK); + b.parent = (struct maple_pnode *)((unsigned long)b.parent & + MAPLE_NODE_MASK); + } + + if (a.parent != b.parent) { + pr_err("The lower 8 bits of parents are different. %p %p\n", + a.parent, b.parent); + return -1; + } + + /* + * If it is a leaf node, the slots do not contain the node address, and + * no special processing of slots is required. + */ + if (ma_is_leaf(type)) + goto cmp; + + slots_a = ma_slots(&a, type); + slots_b = ma_slots(&b, type); + + for (i = 0; i < mt_slots[type]; i++) { + if (!slots_a[i] && !slots_b[i]) + break; + + if (!slots_a[i] || !slots_b[i]) { + pr_err("The number of slots is different.\n"); + return -1; + } + + /* Do not compare addresses in slots. */ + ((unsigned long *)slots_a)[i] &= MAPLE_NODE_MASK; + ((unsigned long *)slots_b)[i] &= MAPLE_NODE_MASK; + } + +cmp: + /* + * Compare all contents of two nodes, including parent (except address), + * slots (except address), pivots, gaps and metadata. + */ + return memcmp(&a, &b, sizeof(struct maple_node)); +} + +/* + * Compare two trees and return 0 if they are the same, non-zero otherwise. + */ +static int __init compare_tree(struct maple_tree *mt_a, struct maple_tree *mt_b) +{ + MA_STATE(mas_a, mt_a, 0, 0); + MA_STATE(mas_b, mt_b, 0, 0); + + if (mt_a->ma_flags != mt_b->ma_flags) { + pr_err("The flags of the two trees are different.\n"); + return -1; + } + + mas_dfs_preorder(&mas_a); + mas_dfs_preorder(&mas_b); + + if (mas_is_ptr(&mas_a) || mas_is_ptr(&mas_b)) { + if (!(mas_is_ptr(&mas_a) && mas_is_ptr(&mas_b))) { + pr_err("One is MAS_ROOT and the other is not.\n"); + return -1; + } + return 0; + } + + while (!mas_is_none(&mas_a) || !mas_is_none(&mas_b)) { + + if (mas_is_none(&mas_a) || mas_is_none(&mas_b)) { + pr_err("One is MAS_NONE and the other is not.\n"); + return -1; + } + + if (mas_a.min != mas_b.min || + mas_a.max != mas_b.max) { + pr_err("mas->min, mas->max do not match.\n"); + return -1; + } + + if (compare_node(mas_a.node, mas_b.node)) { + pr_err("The contents of nodes %p and %p are different.\n", + mas_a.node, mas_b.node); + mt_dump(mt_a, mt_dump_dec); + mt_dump(mt_b, mt_dump_dec); + return -1; + } + + mas_dfs_preorder(&mas_a); + mas_dfs_preorder(&mas_b); + } + + return 0; +} + +static __init void mas_subtree_max_range(struct ma_state *mas) +{ + unsigned long limit = mas->max; + MA_STATE(newmas, mas->tree, 0, 0); + void *entry; + + mas_for_each(mas, entry, limit) { + if (mas->last - mas->index >= + newmas.last - newmas.index) { + newmas = *mas; + } + } + + *mas = newmas; +} + +/* + * build_full_tree() - Build a full tree. + * @mt: The tree to build. + * @flags: Use @flags to build the tree. + * @height: The height of the tree to build. + * + * Build a tree with full leaf nodes and internal nodes. Note that the height + * should not exceed 3, otherwise it will take a long time to build. + * Return: zero if the build is successful, non-zero if it fails. + */ +static __init int build_full_tree(struct maple_tree *mt, unsigned int flags, + int height) +{ + MA_STATE(mas, mt, 0, 0); + unsigned long step; + int ret = 0, cnt = 1; + enum maple_type type; + + mt_init_flags(mt, flags); + mtree_insert_range(mt, 0, ULONG_MAX, xa_mk_value(5), GFP_KERNEL); + + mtree_lock(mt); + + while (1) { + mas_set(&mas, 0); + if (mt_height(mt) < height) { + mas.max = ULONG_MAX; + goto store; + } + + while (1) { + mas_dfs_preorder(&mas); + if (mas_is_none(&mas)) + goto unlock; + + type = mte_node_type(mas.node); + if (mas_data_end(&mas) + 1 < mt_slots[type]) { + mas_set(&mas, mas.min); + goto store; + } + } +store: + mas_subtree_max_range(&mas); + step = mas.last - mas.index; + if (step < 1) { + ret = -1; + goto unlock; + } + + step /= 2; + mas.last = mas.index + step; + mas_store_gfp(&mas, xa_mk_value(5), + GFP_KERNEL); + ++cnt; + } +unlock: + mtree_unlock(mt); + + MT_BUG_ON(mt, mt_height(mt) != height); + /* pr_info("height:%u number of elements:%d\n", mt_height(mt), cnt); */ + return ret; +} + +static noinline void __init check_mtree_dup(struct maple_tree *mt) +{ + DEFINE_MTREE(new); + int i, j, ret, count = 0; + unsigned int rand_seed = 17, rand; + + /* store a value at [0, 0] */ + mt_init_flags(mt, 0); + mtree_store_range(mt, 0, 0, xa_mk_value(0), GFP_KERNEL); + ret = mtree_dup(mt, &new, GFP_KERNEL); + MT_BUG_ON(&new, ret); + mt_validate(&new); + if (compare_tree(mt, &new)) + MT_BUG_ON(&new, 1); + + mtree_destroy(mt); + mtree_destroy(&new); + + /* The two trees have different attributes. */ + mt_init_flags(mt, 0); + mt_init_flags(&new, MT_FLAGS_ALLOC_RANGE); + ret = mtree_dup(mt, &new, GFP_KERNEL); + MT_BUG_ON(&new, ret != -EINVAL); + mtree_destroy(mt); + mtree_destroy(&new); + + /* The new tree is not empty */ + mt_init_flags(mt, 0); + mt_init_flags(&new, 0); + mtree_store(&new, 5, xa_mk_value(5), GFP_KERNEL); + ret = mtree_dup(mt, &new, GFP_KERNEL); + MT_BUG_ON(&new, ret != -EINVAL); + mtree_destroy(mt); + mtree_destroy(&new); + + /* Test for duplicating full trees. */ + for (i = 1; i <= 3; i++) { + ret = build_full_tree(mt, 0, i); + MT_BUG_ON(mt, ret); + mt_init_flags(&new, 0); + + ret = mtree_dup(mt, &new, GFP_KERNEL); + MT_BUG_ON(&new, ret); + mt_validate(&new); + if (compare_tree(mt, &new)) + MT_BUG_ON(&new, 1); + + mtree_destroy(mt); + mtree_destroy(&new); + } + + for (i = 1; i <= 3; i++) { + ret = build_full_tree(mt, MT_FLAGS_ALLOC_RANGE, i); + MT_BUG_ON(mt, ret); + mt_init_flags(&new, MT_FLAGS_ALLOC_RANGE); + + ret = mtree_dup(mt, &new, GFP_KERNEL); + MT_BUG_ON(&new, ret); + mt_validate(&new); + if (compare_tree(mt, &new)) + MT_BUG_ON(&new, 1); + + mtree_destroy(mt); + mtree_destroy(&new); + } + + /* Test for normal duplicating. */ + for (i = 0; i < 1000; i += 3) { + if (i & 1) { + mt_init_flags(mt, 0); + mt_init_flags(&new, 0); + } else { + mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE); + mt_init_flags(&new, MT_FLAGS_ALLOC_RANGE); + } + + for (j = 0; j < i; j++) { + mtree_store_range(mt, j * 10, j * 10 + 5, + xa_mk_value(j), GFP_KERNEL); + } + + ret = mtree_dup(mt, &new, GFP_KERNEL); + MT_BUG_ON(&new, ret); + mt_validate(&new); + if (compare_tree(mt, &new)) + MT_BUG_ON(&new, 1); + + mtree_destroy(mt); + mtree_destroy(&new); + } + + /* Test memory allocation failed. */ + mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE); + for (i = 0; i < 30; i += 3) { + mtree_store_range(mt, j * 10, j * 10 + 5, + xa_mk_value(j), GFP_KERNEL); + } + + /* Failed at the first node. */ + mt_init_flags(&new, MT_FLAGS_ALLOC_RANGE); + mt_set_non_kernel(0); + ret = mtree_dup(mt, &new, GFP_NOWAIT); + mt_set_non_kernel(0); + MT_BUG_ON(&new, ret != -ENOMEM); + mtree_destroy(mt); + mtree_destroy(&new); + + /* Random maple tree fails at a random node. */ + for (i = 0; i < 1000; i += 3) { + if (i & 1) { + mt_init_flags(mt, 0); + mt_init_flags(&new, 0); + } else { + mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE); + mt_init_flags(&new, MT_FLAGS_ALLOC_RANGE); + } + + for (j = 0; j < i; j++) { + mtree_store_range(mt, j * 10, j * 10 + 5, + xa_mk_value(j), GFP_KERNEL); + } + /* + * The rand() library function is not used, so we can generate + * the same random numbers on any platform. + */ + rand_seed = rand_seed * 1103515245 + 12345; + rand = rand_seed / 65536 % 128; + mt_set_non_kernel(rand); + + ret = mtree_dup(mt, &new, GFP_NOWAIT); + mt_set_non_kernel(0); + if (ret != 0) { + MT_BUG_ON(&new, ret != -ENOMEM); + count++; + mtree_destroy(mt); + continue; + } + + mt_validate(&new); + if (compare_tree(mt, &new)) + MT_BUG_ON(&new, 1); + + mtree_destroy(mt); + mtree_destroy(&new); + } + + /* pr_info("mtree_dup() fail %d times\n", count); */ + BUG_ON(!count); +} + extern void test_kmem_cache_bulk(void); void farmer_tests(void) @@ -35904,6 +36261,10 @@ void farmer_tests(void) check_null_expand(&tree); mtree_destroy(&tree); + mt_init_flags(&tree, 0); + check_mtree_dup(&tree); + mtree_destroy(&tree); + /* RCU testing */ mt_init_flags(&tree, 0); check_erase_testset(&tree);