From a88cc108f6f39e56577793f66ac69eb0e18ae099 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 17 Mar 2014 12:21:54 +0000 Subject: lib: Export interval_tree 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 Cc: Michel Lespinasse Cc: Rik van Riel Cc: Peter Zijlstra Cc: Andrea Arcangeli Cc: David Woodhouse Cc: Andrew Morton Reviewed-by: Michel Lespinasse [Acked for inclusion via drm/i915 by Andrew Morton.] [danvet: switch to _GPL as per the mailing list discussion.] Signed-off-by: Daniel Vetter --- lib/interval_tree_test.c | 106 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 106 insertions(+) create mode 100644 lib/interval_tree_test.c (limited to 'lib/interval_tree_test.c') diff --git a/lib/interval_tree_test.c b/lib/interval_tree_test.c new file mode 100644 index 000000000000..245900b98c8e --- /dev/null +++ b/lib/interval_tree_test.c @@ -0,0 +1,106 @@ +#include +#include +#include +#include + +#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"); -- cgit