#include <linux/module.h>#include <linux/interval_tree.h>#include <linux/random.h>#include <asm/timex.h> #define NODES        100#define PERF_LOOPS   100000#define SEARCHES     100#define SEARCH_LOOPS 10000 static struct rb_root root = RB_ROOT;static struct interval_tree_node nodes[NODES];static u32 queries[SEARCHES]; static struct rnd_state rnd; static inline unsigned longsearch(unsigned long query, struct rb_root *root){	struct interval_tree_node *node;	unsigned long results = 0; 	for (node = interval_tree_iter_first(root, query, query); node;	     node = interval_tree_iter_next(node, query, query))		results++;	return results;} static void init(void){	int i;	for (i = 0; i < NODES; i++) {		u32 a = prandom_u32_state(&rnd);		u32 b = prandom_u32_state(&rnd);		if (a <= b) {			nodes[i].start = a;			nodes[i].last = b;		} else {			nodes[i].start = b;			nodes[i].last = a;		}	}	for (i = 0; i < SEARCHES; i++)		queries[i] = prandom_u32_state(&rnd);} static int interval_tree_test_init(void){	int i, j;	unsigned long results;	cycles_t time1, time2, time; 	printk(KERN_ALERT "interval tree insert/remove"); 	prandom_seed_state(&rnd, 3141592653589793238ULL);	init(); 	time1 = get_cycles(); 	for (i = 0; i < PERF_LOOPS; i++) {		for (j = 0; j < NODES; j++)			interval_tree_insert(nodes + j, &root);		for (j = 0; j < NODES; j++)			interval_tree_remove(nodes + j, &root);	} 	time2 = get_cycles();	time = time2 - time1; 	time = div_u64(time, PERF_LOOPS);	printk(" -> %llu cycles\n", (unsigned long long)time); 	printk(KERN_ALERT "interval tree search"); 	for (j = 0; j < NODES; j++)		interval_tree_insert(nodes + j, &root); 	time1 = get_cycles(); 	results = 0;	for (i = 0; i < SEARCH_LOOPS; i++)		for (j = 0; j < SEARCHES; j++)			results += search(queries[j], &root); 	time2 = get_cycles();	time = time2 - time1; 	time = div_u64(time, SEARCH_LOOPS);	results = div_u64(results, SEARCH_LOOPS);	printk(" -> %llu cycles (%lu results)\n",	       (unsigned long long)time, results); 	return -EAGAIN; /* Fail will directly unload the module */} static void interval_tree_test_exit(void){	printk(KERN_ALERT "test exit\n");} module_init(interval_tree_test_init)module_exit(interval_tree_test_exit) MODULE_LICENSE("GPL");MODULE_AUTHOR("Michel Lespinasse");MODULE_DESCRIPTION("Interval Tree test");