[PATCH -next 0/4] lib/interval_tree_test: some debugging improvements

[PATCH -next 0/4] lib/interval_tree_test: some debugging improvements

[Davidlohr Bueso]

Hi,

Here are some patches that update the interva_tree_test module allowing
users to pass finer grained options to run the actual test.

Applies on top of v4.12-rc1.

Thanks!

Davidlohr Bueso (4):
  lib/interval_tree_test: allow the module to be compiled-in
  lib/interval_tree_test: make test options module parameters
  lib/interval_tree_test: allow users to limit scope of endpoint
  lib/interval_tree_test: allow full tree search

 lib/Kconfig.debug        |  2 +-
 lib/interval_tree_test.c | 93 ++++++++++++++++++++++++++++++++----------------
 2 files changed, 63 insertions(+), 32 deletions(-)

-- 
2.12.0

[PATCH 1/4] lib/interval_tree_test: allow the module to be compiled-in

[Davidlohr Bueso]

It is a tristate after all, and also serves well for quick debugging.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
 lib/Kconfig.debug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e4587ebe52c7..b29bf26e653c 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1773,7 +1773,7 @@ config RBTREE_TEST
 
 config INTERVAL_TREE_TEST
 	tristate "Interval tree test"
-	depends on m && DEBUG_KERNEL
+	depends on DEBUG_KERNEL
 	select INTERVAL_TREE
 	help
 	  A benchmark measuring the performance of the interval tree library
-- 
2.12.0

[PATCH 2/4] lib/interval_tree_test: make test options module parameters

[Davidlohr Bueso]

Allows for more flexible debugging.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
 lib/interval_tree_test.c | 57 +++++++++++++++++++++++++++++++++---------------
 1 file changed, 40 insertions(+), 17 deletions(-)

diff --git a/lib/interval_tree_test.c b/lib/interval_tree_test.c
index 245900b98c8e..1093f0496d5e 100644
--- a/lib/interval_tree_test.c
+++ b/lib/interval_tree_test.c
@@ -1,16 +1,25 @@
 #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 NODES        100
-#define PERF_LOOPS   100000
-#define SEARCHES     100
-#define SEARCH_LOOPS 10000
+#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, 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");
+
 
 static struct rb_root root = RB_ROOT;
-static struct interval_tree_node nodes[NODES];
-static u32 queries[SEARCHES];
+static struct interval_tree_node *nodes = NULL;
+static u32 *queries = NULL;
 
 static struct rnd_state rnd;
 
@@ -29,7 +38,8 @@ search(unsigned long query, struct rb_root *root)
 static void init(void)
 {
 	int i;
-	for (i = 0; i < NODES; i++) {
+
+	for (i = 0; i < nnodes; i++) {
 		u32 a = prandom_u32_state(&rnd);
 		u32 b = prandom_u32_state(&rnd);
 		if (a <= b) {
@@ -40,7 +50,7 @@ static void init(void)
 			nodes[i].last = a;
 		}
 	}
-	for (i = 0; i < SEARCHES; i++)
+	for (i = 0; i < nsearches; i++)
 		queries[i] = prandom_u32_state(&rnd);
 }
 
@@ -50,6 +60,16 @@ static int interval_tree_test_init(void)
 	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);
@@ -57,39 +77,42 @@ static int interval_tree_test_init(void)
 
 	time1 = get_cycles();
 
-	for (i = 0; i < PERF_LOOPS; i++) {
-		for (j = 0; j < NODES; j++)
+	for (i = 0; i < perf_loops; i++) {
+		for (j = 0; j < nnodes; j++)
 			interval_tree_insert(nodes + j, &root);
-		for (j = 0; j < NODES; j++)
+		for (j = 0; j < nnodes; j++)
 			interval_tree_remove(nodes + j, &root);
 	}
 
 	time2 = get_cycles();
 	time = time2 - time1;
 
-	time = div_u64(time, PERF_LOOPS);
+	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++)
+	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 < SEARCHES; j++)
+	for (i = 0; i < search_loops; i++)
+		for (j = 0; j < nsearches; j++)
 			results += search(queries[j], &root);
 
 	time2 = get_cycles();
 	time = time2 - time1;
 
-	time = div_u64(time, SEARCH_LOOPS);
-	results = div_u64(results, SEARCH_LOOPS);
+	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 */
 }
 
-- 
2.12.0

[PATCH 3/4] lib/interval_tree_test: allow users to limit scope of endpoint

[Davidlohr Bueso]

Add a 'max_endpoint' parameter such that users may easily
limit the size of the intervals that are randomly generated.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
 lib/interval_tree_test.c | 23 +++++++++++++----------
 1 file 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)
-- 
2.12.0

[PATCH 4/4] lib/interval_tree_test: allow full tree search

[Davidlohr Bueso]

... such that a user can specify visiting all the nodes
in the tree (intersects with the world). This is a nice
opposite from the very basic default query which is a
single point.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
 lib/interval_tree_test.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/lib/interval_tree_test.c b/lib/interval_tree_test.c
index 0fef6364a958..df495fe81421 100644
--- a/lib/interval_tree_test.c
+++ b/lib/interval_tree_test.c
@@ -15,6 +15,7 @@ __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(bool, search_all, false, "Searches will iterate all nodes in the tree");
 
 __param(uint, max_endpoint, ~0, "Largest value for the interval's endpoint");
 
@@ -25,13 +26,13 @@ static u32 *queries = NULL;
 static struct rnd_state rnd;
 
 static inline unsigned long
-search(unsigned long query, struct rb_root *root)
+search(struct rb_root *root, unsigned long start, unsigned long last)
 {
 	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))
+	for (node = interval_tree_iter_first(root, start, last); node;
+	     node = interval_tree_iter_next(node, start, last))
 		results++;
 	return results;
 }
@@ -102,8 +103,12 @@ static int interval_tree_test_init(void)
 
 	results = 0;
 	for (i = 0; i < search_loops; i++)
-		for (j = 0; j < nsearches; j++)
-			results += search(queries[j], &root);
+		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;
-- 
2.12.0