LXR linux/lib/interval_tree

   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