lib/interval_tree_test.c

   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
  11 static struct rb_root root = RB_ROOT;
  12 static struct interval_tree_node nodes[NODES];
  13 static u32 queries[SEARCHES];
  14
  15 static struct rnd_state rnd;
  16
  17 static inline unsigned long
  18 search(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
  29 static 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
  47 static 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
  96 static void interval_tree_test_exit(void)
  97 {
  98         printk(KERN_ALERT "test exit\n");
  99 }
 100
 101 module_init(interval_tree_test_init)
 102 module_exit(interval_tree_test_exit)
 103
 104 MODULE_LICENSE("GPL");
 105 MODULE_AUTHOR("Michel Lespinasse");
 106 MODULE_DESCRIPTION("Interval Tree test");