1#include <linux/module.h>
2#include <linux/interval_tree.h>
3#include <linux/random.h>
4#include <asm/timex.h>
5
6#define NODES        100
7#define PERF_LOOPS   100000
8#define SEARCHES     100
9#define SEARCH_LOOPS 10000
10
11static struct rb_root root = RB_ROOT;
12static struct interval_tree_node nodes[NODES];
13static u32 queries[SEARCHES];
14
15static struct rnd_state rnd;
16
17static inline unsigned long
18search(unsigned long query, struct rb_root *root)
19{
20	struct interval_tree_node *node;
21	unsigned long results = 0;
22
23	for (node = interval_tree_iter_first(root, query, query); node;
24	     node = interval_tree_iter_next(node, query, query))
25		results++;
26	return results;
27}
28
29static void init(void)
30{
31	int i;
32	for (i = 0; i < NODES; i++) {
33		u32 a = prandom_u32_state(&rnd);
34		u32 b = prandom_u32_state(&rnd);
35		if (a <= b) {
36			nodes[i].start = a;
37			nodes[i].last = b;
38		} else {
39			nodes[i].start = b;
40			nodes[i].last = a;
41		}
42	}
43	for (i = 0; i < SEARCHES; i++)
44		queries[i] = prandom_u32_state(&rnd);
45}
46
47static int interval_tree_test_init(void)
48{
49	int i, j;
50	unsigned long results;
51	cycles_t time1, time2, time;
52
53	printk(KERN_ALERT "interval tree insert/remove");
54
55	prandom_seed_state(&rnd, 3141592653589793238ULL);
56	init();
57
58	time1 = get_cycles();
59
60	for (i = 0; i < PERF_LOOPS; i++) {
61		for (j = 0; j < NODES; j++)
62			interval_tree_insert(nodes + j, &root);
63		for (j = 0; j < NODES; j++)
64			interval_tree_remove(nodes + j, &root);
65	}
66
67	time2 = get_cycles();
68	time = time2 - time1;
69
70	time = div_u64(time, PERF_LOOPS);
71	printk(" -> %llu cycles\n", (unsigned long long)time);
72
73	printk(KERN_ALERT "interval tree search");
74
75	for (j = 0; j < NODES; j++)
76		interval_tree_insert(nodes + j, &root);
77
78	time1 = get_cycles();
79
80	results = 0;
81	for (i = 0; i < SEARCH_LOOPS; i++)
82		for (j = 0; j < SEARCHES; j++)
83			results += search(queries[j], &root);
84
85	time2 = get_cycles();
86	time = time2 - time1;
87
88	time = div_u64(time, SEARCH_LOOPS);
89	results = div_u64(results, SEARCH_LOOPS);
90	printk(" -> %llu cycles (%lu results)\n",
91	       (unsigned long long)time, results);
92
93	return -EAGAIN; /* Fail will directly unload the module */
94}
95
96static void interval_tree_test_exit(void)
97{
98	printk(KERN_ALERT "test exit\n");
99}
100
101module_init(interval_tree_test_init)
102module_exit(interval_tree_test_exit)
103
104MODULE_LICENSE("GPL");
105MODULE_AUTHOR("Michel Lespinasse");
106MODULE_DESCRIPTION("Interval Tree test");
107