LXR linux/lib/interval_tree

   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(nnodes * sizeof(struct interval_tree_node), GFP_KERNEL);
  68        if (!nodes)
  69                return -ENOMEM;
  70
  71        queries = kmalloc(nsearches * sizeof(int), GFP_KERNEL);
  72        if (!queries) {
  73                kfree(nodes);
  74                return -ENOMEM;
  75        }
  76
  77        printk(KERN_ALERT "interval tree insert/remove");
  78
  79        prandom_seed_state(&rnd, 3141592653589793238ULL);
  80        init();
  81
  82        time1 = get_cycles();
  83
  84        for (i = 0; i < perf_loops; i++) {
  85                for (j = 0; j < nnodes; j++)
  86                        interval_tree_insert(nodes + j, &root);
  87                for (j = 0; j < nnodes; j++)
  88                        interval_tree_remove(nodes + j, &root);
  89        }
  90
  91        time2 = get_cycles();
  92        time = time2 - time1;
  93
  94        time = div_u64(time, perf_loops);
  95        printk(" -> %llu cycles\n", (unsigned long long)time);
  96
  97        printk(KERN_ALERT "interval tree search");
  98
  99        for (j = 0; j < nnodes; j++)
 100                interval_tree_insert(nodes + j, &root);
 101
 102        time1 = get_cycles();
 103
 104        results = 0;
 105        for (i = 0; i < search_loops; i++)
 106                for (j = 0; j < nsearches; j++) {
 107                        unsigned long start = search_all ? 0 : queries[j];
 108                        unsigned long last = search_all ? max_endpoint : queries[j];
 109
 110                        results += search(&root, start, last);
 111                }
 112
 113        time2 = get_cycles();
 114        time = time2 - time1;
 115
 116        time = div_u64(time, search_loops);
 117        results = div_u64(results, search_loops);
 118        printk(" -> %llu cycles (%lu results)\n",
 119               (unsigned long long)time, results);
 120
 121        kfree(queries);
 122        kfree(nodes);
 123
 124        return -EAGAIN; /* Fail will directly unload the module */
 125}
 126
 127static void interval_tree_test_exit(void)
 128{
 129        printk(KERN_ALERT "test exit\n");
 130}
 131
 132module_init(interval_tree_test_init)
 133module_exit(interval_tree_test_exit)
 134
 135MODULE_LICENSE("GPL");
 136MODULE_AUTHOR("Michel Lespinasse");
 137MODULE_DESCRIPTION("Interval Tree test");
 138