linux/lib/interval_tree_test.c
Davidlohr Bueso 0b548e33e6 lib/rbtree-test: lower default params
Fengguang reported soft lockups while running the rbtree and interval
tree test modules.  The logic for these tests all occur in init phase,
and we currently are pounding with the default values for number of
nodes and number of iterations of each test.  Reduce the latter by two
orders of magnitude.  This does not influence the value of the tests in
that one thousand times by default is enough to get the picture.

Link: http://lkml.kernel.org/r/20171109161715.xai2dtwqw2frhkcm@linux-n805
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:02 -08:00

138 lines
3.4 KiB
C

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/interval_tree.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <asm/timex.h>
#define __param(type, name, init, msg) \
static type name = init; \
module_param(name, type, 0444); \
MODULE_PARM_DESC(name, msg);
__param(int, nnodes, 100, "Number of nodes in the interval tree");
__param(int, perf_loops, 1000, "Number of iterations modifying the tree");
__param(int, nsearches, 100, "Number of searches to the interval tree");
__param(int, search_loops, 1000, "Number of iterations searching the tree");
__param(bool, search_all, false, "Searches will iterate all nodes in the tree");
__param(uint, max_endpoint, ~0, "Largest value for the interval's endpoint");
static struct rb_root_cached root = RB_ROOT_CACHED;
static struct interval_tree_node *nodes = NULL;
static u32 *queries = NULL;
static struct rnd_state rnd;
static inline unsigned long
search(struct rb_root_cached *root, unsigned long start, unsigned long last)
{
struct interval_tree_node *node;
unsigned long results = 0;
for (node = interval_tree_iter_first(root, start, last); node;
node = interval_tree_iter_next(node, start, last))
results++;
return results;
}
static void init(void)
{
int i;
for (i = 0; i < nnodes; i++) {
u32 b = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
u32 a = (prandom_u32_state(&rnd) >> 4) % b;
nodes[i].start = a;
nodes[i].last = b;
}
/*
* Limit the search scope to what the user defined.
* Otherwise we are merely measuring empty walks,
* which is pointless.
*/
for (i = 0; i < nsearches; i++)
queries[i] = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
}
static int interval_tree_test_init(void)
{
int i, j;
unsigned long results;
cycles_t time1, time2, time;
nodes = kmalloc(nnodes * sizeof(struct interval_tree_node), GFP_KERNEL);
if (!nodes)
return -ENOMEM;
queries = kmalloc(nsearches * sizeof(int), GFP_KERNEL);
if (!queries) {
kfree(nodes);
return -ENOMEM;
}
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 < nnodes; j++)
interval_tree_insert(nodes + j, &root);
for (j = 0; j < nnodes; 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 < nnodes; j++)
interval_tree_insert(nodes + j, &root);
time1 = get_cycles();
results = 0;
for (i = 0; i < search_loops; i++)
for (j = 0; j < nsearches; j++) {
unsigned long start = search_all ? 0 : queries[j];
unsigned long last = search_all ? max_endpoint : queries[j];
results += search(&root, start, last);
}
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);
kfree(queries);
kfree(nodes);
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");