lib/interval_tree_test.c

   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, 100000, "Number of iterations modifying the tree");
  15
  16 __param(int, nsearches, 100, "Number of searches to the interval tree");
  17 __param(int, search_loops, 10000, "Number of iterations searching the tree");
  18
  19
  20 static struct rb_root root = RB_ROOT;
  21 static struct interval_tree_node *nodes = NULL;
  22 static u32 *queries = NULL;
  23
  24 static struct rnd_state rnd;
  25
  26 static inline unsigned long
  27 search(unsigned long query, struct rb_root *root)
  28 {
  29         struct interval_tree_node *node;
  30         unsigned long results = 0;
  31
  32         for (node = interval_tree_iter_first(root, query, query); node;
  33              node = interval_tree_iter_next(node, query, query))
  34                 results++;
  35         return results;
  36 }
  37
  38 static void init(void)
  39 {
  40         int i;
  41
  42         for (i = 0; i < nnodes; i++) {
  43                 u32 a = prandom_u32_state(&rnd);
  44                 u32 b = prandom_u32_state(&rnd);
  45                 if (a <= b) {
  46                         nodes[i].start = a;
  47                         nodes[i].last = b;
  48                 } else {
  49                         nodes[i].start = b;
  50                         nodes[i].last = a;
  51                 }
  52         }
  53         for (i = 0; i < nsearches; i++)
  54                 queries[i] = prandom_u32_state(&rnd);
  55 }
  56
  57 static int interval_tree_test_init(void)
  58 {
  59         int i, j;
  60         unsigned long results;
  61         cycles_t time1, time2, time;
  62
  63         nodes = kmalloc(nnodes * sizeof(struct interval_tree_node), GFP_KERNEL);
  64         if (!nodes)
  65                 return -ENOMEM;
  66
  67         queries = kmalloc(nsearches * sizeof(int), GFP_KERNEL);
  68         if (!queries) {
  69                 kfree(nodes);
  70                 return -ENOMEM;
  71         }
  72
  73         printk(KERN_ALERT "interval tree insert/remove");
  74
  75         prandom_seed_state(&rnd, 3141592653589793238ULL);
  76         init();
  77
  78         time1 = get_cycles();
  79
  80         for (i = 0; i < perf_loops; i++) {
  81                 for (j = 0; j < nnodes; j++)
  82                         interval_tree_insert(nodes + j, &root);
  83                 for (j = 0; j < nnodes; j++)
  84                         interval_tree_remove(nodes + j, &root);
  85         }
  86
  87         time2 = get_cycles();
  88         time = time2 - time1;
  89
  90         time = div_u64(time, perf_loops);
  91         printk(" -> %llu cycles\n", (unsigned long long)time);
  92
  93         printk(KERN_ALERT "interval tree search");
  94
  95         for (j = 0; j < nnodes; j++)
  96                 interval_tree_insert(nodes + j, &root);
  97
  98         time1 = get_cycles();
  99
 100         results = 0;
 101         for (i = 0; i < search_loops; i++)
 102                 for (j = 0; j < nsearches; j++)
 103                         results += search(queries[j], &root);
 104
 105         time2 = get_cycles();
 106         time = time2 - time1;
 107
 108         time = div_u64(time, search_loops);
 109         results = div_u64(results, search_loops);
 110         printk(" -> %llu cycles (%lu results)\n",
 111                (unsigned long long)time, results);
 112
 113         kfree(queries);
 114         kfree(nodes);
 115
 116         return -EAGAIN; /* Fail will directly unload the module */
 117 }
 118
 119 static void interval_tree_test_exit(void)
 120 {
 121         printk(KERN_ALERT "test exit\n");
 122 }
 123
 124 module_init(interval_tree_test_init)
 125 module_exit(interval_tree_test_exit)
 126
 127 MODULE_LICENSE("GPL");
 128 MODULE_AUTHOR("Michel Lespinasse");
 129 MODULE_DESCRIPTION("Interval Tree test");