1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/module.h>
3 #include <linux/moduleparam.h>
4 #include <linux/interval_tree.h>
5 #include <linux/random.h>
6 #include <linux/slab.h>
7 #include <asm/timex.h>
8
9 #define __param(type, name, init, msg) \
10 static type name = init; \
11 module_param(name, type, 0444); \
12 MODULE_PARM_DESC(name, msg);
13
14 __param(int, nnodes, 100, "Number of nodes in the interval tree");
15 __param(int, perf_loops, 1000, "Number of iterations modifying the tree");
16
17 __param(int, nsearches, 100, "Number of searches to the interval tree");
18 __param(int, search_loops, 1000, "Number of iterations searching the tree");
19 __param(bool, search_all, false, "Searches will iterate all nodes in the tree");
20
21 __param(uint, max_endpoint, ~0, "Largest value for the interval's endpoint");
22
23 static struct rb_root_cached root = RB_ROOT_CACHED;
24 static struct interval_tree_node *nodes = NULL;
25 static u32 *queries = NULL;
26
27 static struct rnd_state rnd;
28
29 static inline unsigned long
search(struct rb_root_cached * root,unsigned long start,unsigned long last)30 search(struct rb_root_cached *root, unsigned long start, unsigned long last)
31 {
32 struct interval_tree_node *node;
33 unsigned long results = 0;
34
35 for (node = interval_tree_iter_first(root, start, last); node;
36 node = interval_tree_iter_next(node, start, last))
37 results++;
38 return results;
39 }
40
init(void)41 static void init(void)
42 {
43 int i;
44
45 for (i = 0; i < nnodes; i++) {
46 u32 b = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
47 u32 a = (prandom_u32_state(&rnd) >> 4) % b;
48
49 nodes[i].start = a;
50 nodes[i].last = b;
51 }
52
53 /*
54 * Limit the search scope to what the user defined.
55 * Otherwise we are merely measuring empty walks,
56 * which is pointless.
57 */
58 for (i = 0; i < nsearches; i++)
59 queries[i] = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
60 }
61
interval_tree_test_init(void)62 static int interval_tree_test_init(void)
63 {
64 int i, j;
65 unsigned long results;
66 cycles_t time1, time2, time;
67
68 nodes = kmalloc_array(nnodes, sizeof(struct interval_tree_node),
69 GFP_KERNEL);
70 if (!nodes)
71 return -ENOMEM;
72
73 queries = kmalloc_array(nsearches, sizeof(int), GFP_KERNEL);
74 if (!queries) {
75 kfree(nodes);
76 return -ENOMEM;
77 }
78
79 printk(KERN_ALERT "interval tree insert/remove");
80
81 prandom_seed_state(&rnd, 3141592653589793238ULL);
82 init();
83
84 time1 = get_cycles();
85
86 for (i = 0; i < perf_loops; i++) {
87 for (j = 0; j < nnodes; j++)
88 interval_tree_insert(nodes + j, &root);
89 for (j = 0; j < nnodes; j++)
90 interval_tree_remove(nodes + j, &root);
91 }
92
93 time2 = get_cycles();
94 time = time2 - time1;
95
96 time = div_u64(time, perf_loops);
97 printk(" -> %llu cycles\n", (unsigned long long)time);
98
99 printk(KERN_ALERT "interval tree search");
100
101 for (j = 0; j < nnodes; j++)
102 interval_tree_insert(nodes + j, &root);
103
104 time1 = get_cycles();
105
106 results = 0;
107 for (i = 0; i < search_loops; i++)
108 for (j = 0; j < nsearches; j++) {
109 unsigned long start = search_all ? 0 : queries[j];
110 unsigned long last = search_all ? max_endpoint : queries[j];
111
112 results += search(&root, start, last);
113 }
114
115 time2 = get_cycles();
116 time = time2 - time1;
117
118 time = div_u64(time, search_loops);
119 results = div_u64(results, search_loops);
120 printk(" -> %llu cycles (%lu results)\n",
121 (unsigned long long)time, results);
122
123 kfree(queries);
124 kfree(nodes);
125
126 return -EAGAIN; /* Fail will directly unload the module */
127 }
128
interval_tree_test_exit(void)129 static void interval_tree_test_exit(void)
130 {
131 printk(KERN_ALERT "test exit\n");
132 }
133
134 module_init(interval_tree_test_init)
135 module_exit(interval_tree_test_exit)
136
137 MODULE_LICENSE("GPL");
138 MODULE_AUTHOR("Michel Lespinasse");
139 MODULE_DESCRIPTION("Interval Tree test");
140