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