1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/module.h>
3 #include <linux/moduleparam.h>
4 #include <linux/rbtree_augmented.h>
5 #include <linux/random.h>
6 #include <linux/slab.h>
9 #define __param(type, name, init, msg) \
10 static type name = init; \
11 module_param(name, type, 0444); \
12 MODULE_PARM_DESC(name, msg);
14 __param(int, nnodes, 100, "Number of nodes in the rb-tree");
15 __param(int, perf_loops, 1000, "Number of iterations modifying the rb-tree");
16 __param(int, check_loops, 100, "Number of iterations modifying and verifying the rb-tree");
22 /* following fields used for testing augmented rbtree functionality */
27 static struct rb_root_cached root = RB_ROOT_CACHED;
28 static struct test_node *nodes = NULL;
30 static struct rnd_state rnd;
32 static void insert(struct test_node *node, struct rb_root_cached *root)
34 struct rb_node **new = &root->rb_root.rb_node, *parent = NULL;
39 if (key < rb_entry(parent, struct test_node, rb)->key)
40 new = &parent->rb_left;
42 new = &parent->rb_right;
45 rb_link_node(&node->rb, parent, new);
46 rb_insert_color(&node->rb, &root->rb_root);
49 static void insert_cached(struct test_node *node, struct rb_root_cached *root)
51 struct rb_node **new = &root->rb_root.rb_node, *parent = NULL;
57 if (key < rb_entry(parent, struct test_node, rb)->key)
58 new = &parent->rb_left;
60 new = &parent->rb_right;
65 rb_link_node(&node->rb, parent, new);
66 rb_insert_color_cached(&node->rb, root, leftmost);
69 static inline void erase(struct test_node *node, struct rb_root_cached *root)
71 rb_erase(&node->rb, &root->rb_root);
74 static inline void erase_cached(struct test_node *node, struct rb_root_cached *root)
76 rb_erase_cached(&node->rb, root);
80 #define NODE_VAL(node) ((node)->val)
82 RB_DECLARE_CALLBACKS_MAX(static, augment_callbacks,
83 struct test_node, rb, u32, augmented, NODE_VAL)
85 static void insert_augmented(struct test_node *node,
86 struct rb_root_cached *root)
88 struct rb_node **new = &root->rb_root.rb_node, *rb_parent = NULL;
91 struct test_node *parent;
95 parent = rb_entry(rb_parent, struct test_node, rb);
96 if (parent->augmented < val)
97 parent->augmented = val;
98 if (key < parent->key)
99 new = &parent->rb.rb_left;
101 new = &parent->rb.rb_right;
104 node->augmented = val;
105 rb_link_node(&node->rb, rb_parent, new);
106 rb_insert_augmented(&node->rb, &root->rb_root, &augment_callbacks);
109 static void insert_augmented_cached(struct test_node *node,
110 struct rb_root_cached *root)
112 struct rb_node **new = &root->rb_root.rb_node, *rb_parent = NULL;
115 struct test_node *parent;
116 bool leftmost = true;
120 parent = rb_entry(rb_parent, struct test_node, rb);
121 if (parent->augmented < val)
122 parent->augmented = val;
123 if (key < parent->key)
124 new = &parent->rb.rb_left;
126 new = &parent->rb.rb_right;
131 node->augmented = val;
132 rb_link_node(&node->rb, rb_parent, new);
133 rb_insert_augmented_cached(&node->rb, root,
134 leftmost, &augment_callbacks);
138 static void erase_augmented(struct test_node *node, struct rb_root_cached *root)
140 rb_erase_augmented(&node->rb, &root->rb_root, &augment_callbacks);
143 static void erase_augmented_cached(struct test_node *node,
144 struct rb_root_cached *root)
146 rb_erase_augmented_cached(&node->rb, root, &augment_callbacks);
149 static void init(void)
152 for (i = 0; i < nnodes; i++) {
153 nodes[i].key = prandom_u32_state(&rnd);
154 nodes[i].val = prandom_u32_state(&rnd);
158 static bool is_red(struct rb_node *rb)
160 return !(rb->__rb_parent_color & 1);
163 static int black_path_count(struct rb_node *rb)
166 for (count = 0; rb; rb = rb_parent(rb))
167 count += !is_red(rb);
171 static void check_postorder_foreach(int nr_nodes)
173 struct test_node *cur, *n;
175 rbtree_postorder_for_each_entry_safe(cur, n, &root.rb_root, rb)
178 WARN_ON_ONCE(count != nr_nodes);
181 static void check_postorder(int nr_nodes)
185 for (rb = rb_first_postorder(&root.rb_root); rb; rb = rb_next_postorder(rb))
188 WARN_ON_ONCE(count != nr_nodes);
191 static void check(int nr_nodes)
194 int count = 0, blacks = 0;
197 for (rb = rb_first(&root.rb_root); rb; rb = rb_next(rb)) {
198 struct test_node *node = rb_entry(rb, struct test_node, rb);
199 WARN_ON_ONCE(node->key < prev_key);
200 WARN_ON_ONCE(is_red(rb) &&
201 (!rb_parent(rb) || is_red(rb_parent(rb))));
203 blacks = black_path_count(rb);
205 WARN_ON_ONCE((!rb->rb_left || !rb->rb_right) &&
206 blacks != black_path_count(rb));
207 prev_key = node->key;
211 WARN_ON_ONCE(count != nr_nodes);
212 WARN_ON_ONCE(count < (1 << black_path_count(rb_last(&root.rb_root))) - 1);
214 check_postorder(nr_nodes);
215 check_postorder_foreach(nr_nodes);
218 static void check_augmented(int nr_nodes)
223 for (rb = rb_first(&root.rb_root); rb; rb = rb_next(rb)) {
224 struct test_node *node = rb_entry(rb, struct test_node, rb);
225 u32 subtree, max = node->val;
226 if (node->rb.rb_left) {
227 subtree = rb_entry(node->rb.rb_left, struct test_node,
232 if (node->rb.rb_right) {
233 subtree = rb_entry(node->rb.rb_right, struct test_node,
238 WARN_ON_ONCE(node->augmented != max);
242 static int __init rbtree_test_init(void)
245 cycles_t time1, time2, time;
246 struct rb_node *node;
248 nodes = kmalloc_array(nnodes, sizeof(*nodes), GFP_KERNEL);
252 printk(KERN_ALERT "rbtree testing");
254 prandom_seed_state(&rnd, 3141592653589793238ULL);
257 time1 = get_cycles();
259 for (i = 0; i < perf_loops; i++) {
260 for (j = 0; j < nnodes; j++)
261 insert(nodes + j, &root);
262 for (j = 0; j < nnodes; j++)
263 erase(nodes + j, &root);
266 time2 = get_cycles();
267 time = time2 - time1;
269 time = div_u64(time, perf_loops);
270 printk(" -> test 1 (latency of nnodes insert+delete): %llu cycles\n",
271 (unsigned long long)time);
273 time1 = get_cycles();
275 for (i = 0; i < perf_loops; i++) {
276 for (j = 0; j < nnodes; j++)
277 insert_cached(nodes + j, &root);
278 for (j = 0; j < nnodes; j++)
279 erase_cached(nodes + j, &root);
282 time2 = get_cycles();
283 time = time2 - time1;
285 time = div_u64(time, perf_loops);
286 printk(" -> test 2 (latency of nnodes cached insert+delete): %llu cycles\n",
287 (unsigned long long)time);
289 for (i = 0; i < nnodes; i++)
290 insert(nodes + i, &root);
292 time1 = get_cycles();
294 for (i = 0; i < perf_loops; i++) {
295 for (node = rb_first(&root.rb_root); node; node = rb_next(node))
299 time2 = get_cycles();
300 time = time2 - time1;
302 time = div_u64(time, perf_loops);
303 printk(" -> test 3 (latency of inorder traversal): %llu cycles\n",
304 (unsigned long long)time);
306 time1 = get_cycles();
308 for (i = 0; i < perf_loops; i++)
309 node = rb_first(&root.rb_root);
311 time2 = get_cycles();
312 time = time2 - time1;
314 time = div_u64(time, perf_loops);
315 printk(" -> test 4 (latency to fetch first node)\n");
316 printk(" non-cached: %llu cycles\n", (unsigned long long)time);
318 time1 = get_cycles();
320 for (i = 0; i < perf_loops; i++)
321 node = rb_first_cached(&root);
323 time2 = get_cycles();
324 time = time2 - time1;
326 time = div_u64(time, perf_loops);
327 printk(" cached: %llu cycles\n", (unsigned long long)time);
329 for (i = 0; i < nnodes; i++)
330 erase(nodes + i, &root);
333 for (i = 0; i < check_loops; i++) {
335 for (j = 0; j < nnodes; j++) {
337 insert(nodes + j, &root);
339 for (j = 0; j < nnodes; j++) {
341 erase(nodes + j, &root);
346 printk(KERN_ALERT "augmented rbtree testing");
350 time1 = get_cycles();
352 for (i = 0; i < perf_loops; i++) {
353 for (j = 0; j < nnodes; j++)
354 insert_augmented(nodes + j, &root);
355 for (j = 0; j < nnodes; j++)
356 erase_augmented(nodes + j, &root);
359 time2 = get_cycles();
360 time = time2 - time1;
362 time = div_u64(time, perf_loops);
363 printk(" -> test 1 (latency of nnodes insert+delete): %llu cycles\n", (unsigned long long)time);
365 time1 = get_cycles();
367 for (i = 0; i < perf_loops; i++) {
368 for (j = 0; j < nnodes; j++)
369 insert_augmented_cached(nodes + j, &root);
370 for (j = 0; j < nnodes; j++)
371 erase_augmented_cached(nodes + j, &root);
374 time2 = get_cycles();
375 time = time2 - time1;
377 time = div_u64(time, perf_loops);
378 printk(" -> test 2 (latency of nnodes cached insert+delete): %llu cycles\n", (unsigned long long)time);
380 for (i = 0; i < check_loops; i++) {
382 for (j = 0; j < nnodes; j++) {
384 insert_augmented(nodes + j, &root);
386 for (j = 0; j < nnodes; j++) {
387 check_augmented(nnodes - j);
388 erase_augmented(nodes + j, &root);
395 return -EAGAIN; /* Fail will directly unload the module */
398 static void __exit rbtree_test_exit(void)
400 printk(KERN_ALERT "test exit\n");
403 module_init(rbtree_test_init)
404 module_exit(rbtree_test_exit)
406 MODULE_LICENSE("GPL");
407 MODULE_AUTHOR("Michel Lespinasse");
408 MODULE_DESCRIPTION("Red Black Tree test");