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| author | Davidlohr Bueso <dave@stgolabs.net> | 2017-07-10 15:51:49 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-07-10 16:32:35 -0700 |
| commit | a8ec14d4f6aa8e245efacc992c8ee6ea0464ce2a (patch) | |
| tree | eb6eaca9080f9cbdb6d17af2ebf64c80175daa52 /lib/interval_tree_test.c | |
| parent | a54dae0338b7f01eb0f9c7571fb9b74f791d1c6b (diff) | |
| download | lwn-a8ec14d4f6aa8e245efacc992c8ee6ea0464ce2a.tar.gz lwn-a8ec14d4f6aa8e245efacc992c8ee6ea0464ce2a.zip | |
lib/interval_tree_test.c: allow users to limit scope of endpoint
Add a 'max_endpoint' parameter such that users may easily limit the size
of the intervals that are randomly generated.
Link: http://lkml.kernel.org/r/20170518174936.20265-4-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/interval_tree_test.c')
| -rw-r--r-- | lib/interval_tree_test.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/lib/interval_tree_test.c b/lib/interval_tree_test.c index 1093f0496d5e..0fef6364a958 100644 --- a/lib/interval_tree_test.c +++ b/lib/interval_tree_test.c @@ -16,6 +16,7 @@ __param(int, perf_loops, 100000, "Number of iterations modifying the tree"); __param(int, nsearches, 100, "Number of searches to the interval tree"); __param(int, search_loops, 10000, "Number of iterations searching the tree"); +__param(uint, max_endpoint, ~0, "Largest value for the interval's endpoint"); static struct rb_root root = RB_ROOT; static struct interval_tree_node *nodes = NULL; @@ -40,18 +41,20 @@ static void init(void) int i; for (i = 0; i < nnodes; 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; - } + 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); + queries[i] = (prandom_u32_state(&rnd) >> 4) % max_endpoint; } static int interval_tree_test_init(void) |