mirror of
https://github.com/torvalds/linux.git
synced 2024-11-27 06:31:52 +00:00
a88cc108f6
lib/interval_tree.c provides a simple interface for an interval-tree
(an augmented red-black tree) but is only built when testing the generic
macros for building interval-trees. For drivers with modest needs,
export the simple interval-tree library as is.
v2: Lots of help from Michel Lespinasse to only compile the code
as required:
- make INTERVAL_TREE a config option
- make INTERVAL_TREE_TEST select the library functions
and sanitize the filenames & Makefile
- prepare interval_tree for being built as a module if required
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
[Acked for inclusion via drm/i915 by Andrew Morton.]
[danvet: switch to _GPL as per the mailing list discussion.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
107 lines
2.3 KiB
C
107 lines
2.3 KiB
C
#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 long
|
|
search(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");
|